text: /*-------------------------------------------------------------------------
   *
   * copy.c
   *		Implements the COPY utility command
   *
   * Portions Copyright (c) 1996-2018, PostgreSQL Global Development Group
   * Portions Copyright (c) 1994, Regents of the University of California
   *
   *
   * IDENTIFICATION
   *	  src/backend/commands/copy.c
   *
   *-------------------------------------------------------------------------
   */
  #include "postgres.h"
  
  #include <ctype.h>
  #include <unistd.h>
  #include <sys/stat.h>
  
  #include "access/heapam.h"
  #include "access/htup_details.h"
  #include "access/sysattr.h"
  #include "access/xact.h"
  #include "access/xlog.h"
  #include "catalog/dependency.h"
  #include "catalog/pg_authid.h"
  #include "catalog/pg_type.h"
  #include "commands/copy.h"
  #include "commands/defrem.h"
  #include "commands/trigger.h"
  #include "executor/execPartition.h"
  #include "executor/executor.h"
  #include "foreign/fdwapi.h"
  #include "libpq/libpq.h"
  #include "libpq/pqformat.h"
  #include "mb/pg_wchar.h"
  #include "miscadmin.h"
  #include "optimizer/clauses.h"
  #include "optimizer/planner.h"
  #include "nodes/makefuncs.h"
  #include "parser/parse_relation.h"
  #include "port/pg_bswap.h"
  #include "rewrite/rewriteHandler.h"
  #include "storage/fd.h"
  #include "tcop/tcopprot.h"
  #include "utils/builtins.h"
  #include "utils/lsyscache.h"
  #include "utils/memutils.h"
  #include "utils/portal.h"
  #include "utils/rel.h"
  #include "utils/rls.h"
  #include "utils/snapmgr.h"
  #include "pg_yb_utils.h"
  #include "executor/ybcModifyTable.h"
  
  
  
  #define ISOCTAL(c) (((c) >= '0') && ((c) <= '7'))
  #define OCTVALUE(c) ((c) - '0')
  
  /*
   * Represents the different source/dest cases we need to worry about at
   * the bottom level
   */
  typedef enum CopyDest
  {
  	COPY_FILE,					/* to/from file (or a piped program) */
  	COPY_OLD_FE,				/* to/from frontend (2.0 protocol) */
  	COPY_NEW_FE,				/* to/from frontend (3.0 protocol) */
  	COPY_CALLBACK				/* to/from callback function */
  } CopyDest;
  
  /*
   *	Represents the end-of-line terminator type of the input
   */
  typedef enum EolType
  {
  	EOL_UNKNOWN,
  	EOL_NL,
  	EOL_CR,
  	EOL_CRNL
  } EolType;
  
  /*
   * This struct contains all the state variables used throughout a COPY
   * operation. For simplicity, we use the same struct for all variants of COPY,
   * even though some fields are used in only some cases.
   *
   * Multi-byte encodings: all supported client-side encodings encode multi-byte
   * characters by having the first byte's high bit set. Subsequent bytes of the
   * character can have the high bit not set. When scanning data in such an
   * encoding to look for a match to a single-byte (ie ASCII) character, we must
   * use the full pg_encoding_mblen() machinery to skip over multibyte
   * characters, else we might find a false match to a trailing byte. In
   * supported server encodings, there is no possibility of a false match, and
   * it's faster to make useless comparisons to trailing bytes than it is to
   * invoke pg_encoding_mblen() to skip over them. encoding_embeds_ascii is true
   * when we have to do it the hard way.
   */
  typedef struct CopyStateData
  {
  	/* low-level state data */
  	CopyDest	copy_dest;		/* type of copy source/destination */
  	FILE	   *copy_file;		/* used if copy_dest == COPY_FILE */
  	StringInfo	fe_msgbuf;		/* used for all dests during COPY TO, only for
  								 * dest == COPY_NEW_FE in COPY FROM */
  	bool		is_copy_from;	/* COPY TO, or COPY FROM? */
  	bool		reached_eof;	/* true if we read to end of copy data (not
  								 * all copy_dest types maintain this) */
  	EolType		eol_type;		/* EOL type of input */
  	int			file_encoding;	/* file or remote side's character encoding */
  	bool		need_transcoding;	/* file encoding diff from server? */
  	bool		encoding_embeds_ascii;	/* ASCII can be non-first byte? */
  
  	/* parameters from the COPY command */
  	Relation	rel;			/* relation to copy to or from */
  	QueryDesc  *queryDesc;		/* executable query to copy from */
  	List	   *attnumlist;		/* integer list of attnums to copy */
  	char	   *filename;		/* filename, or NULL for STDIN/STDOUT */
  	bool		is_program;		/* is 'filename' a program to popen? */
  	copy_data_source_cb data_source_cb; /* function for reading data */
  	bool		binary;			/* binary format? */
  	bool		oids;			/* include OIDs? */
  	bool		freeze;			/* freeze rows on loading? */
  	bool		csv_mode;		/* Comma Separated Value format? */
  	bool		header_line;	/* CSV header line? */
  	char	   *null_print;		/* NULL marker string (server encoding!) */
  	int			null_print_len; /* length of same */
  	char	   *null_print_client;	/* same converted to file encoding */
  	char	   *delim;			/* column delimiter (must be 1 byte) */
  	char	   *quote;			/* CSV quote char (must be 1 byte) */
  	char	   *escape;			/* CSV escape char (must be 1 byte) */
  	List	   *force_quote;	/* list of column names */
  	bool		force_quote_all;	/* FORCE_QUOTE *? */
  	bool	   *force_quote_flags;	/* per-column CSV FQ flags */
  	List	   *force_notnull;	/* list of column names */
  	bool	   *force_notnull_flags;	/* per-column CSV FNN flags */
  	List	   *force_null;		/* list of column names */
  	bool	   *force_null_flags;	/* per-column CSV FN flags */
  	bool		convert_selectively;	/* do selective binary conversion? */
  	List	   *convert_select; /* list of column names (can be NIL) */
  	bool	   *convert_select_flags;	/* per-column CSV/TEXT CS flags */
  
  	/* these are just for error messages, see CopyFromErrorCallback */
  	const char *cur_relname;	/* table name for error messages */
  	uint64		cur_lineno;		/* line number for error messages */
  	const char *cur_attname;	/* current att for error messages */
  	const char *cur_attval;		/* current att value for error messages */
  
  	/*
  	 * Working state for COPY TO/FROM
  	 */
  	MemoryContext copycontext;	/* per-copy execution context */
  
  	/*
  	 * Working state for COPY TO
  	 */
  	FmgrInfo   *out_functions;	/* lookup info for output functions */
  	MemoryContext rowcontext;	/* per-row evaluation context */
  
  	/*
  	 * Working state for COPY FROM
  	 */
  	AttrNumber	num_defaults;
  	bool		file_has_oids;
  	FmgrInfo	oid_in_function;
  	Oid			oid_typioparam;
  	FmgrInfo   *in_functions;	/* array of input functions for each attrs */
  	Oid		   *typioparams;	/* array of element types for in_functions */
  	int		   *defmap;			/* array of default att numbers */
  	ExprState **defexprs;		/* array of default att expressions */
  	bool		volatile_defexprs;	/* is any of defexprs volatile? */
  	List	   *range_table;
  
  	/* Tuple-routing support info */
  	PartitionTupleRouting *partition_tuple_routing;
  
  	TransitionCaptureState *transition_capture;
  
  	/*
  	 * These variables are used to reduce overhead in textual COPY FROM.
  	 *
  	 * attribute_buf holds the separated, de-escaped text for each field of
  	 * the current line.  The CopyReadAttributes functions return arrays of
  	 * pointers into this buffer.  We avoid palloc/pfree overhead by re-using
  	 * the buffer on each cycle.
  	 */
  	StringInfoData attribute_buf;
  
  	/* field raw data pointers found by COPY FROM */
  
  	int			max_fields;
  	char	  **raw_fields;
  
  	/*
  	 * Similarly, line_buf holds the whole input line being processed. The
  	 * input cycle is first to read the whole line into line_buf, convert it
  	 * to server encoding there, and then extract the individual attribute
  	 * fields into attribute_buf.  line_buf is preserved unmodified so that we
  	 * can display it in error messages if appropriate.
  	 */
  	StringInfoData line_buf;
  	bool		line_buf_converted; /* converted to server encoding? */
  	bool		line_buf_valid; /* contains the row being processed? */
  
  	/*
  	 * Finally, raw_buf holds raw data read from the data source (file or
  	 * client connection).  CopyReadLine parses this data sufficiently to
  	 * locate line boundaries, then transfers the data to line_buf and
  	 * converts it.  Note: we guarantee that there is a \0 at
  	 * raw_buf[raw_buf_len].
  	 */
  #define RAW_BUF_SIZE 65536		/* we palloc RAW_BUF_SIZE+1 bytes */
  	char	   *raw_buf;
  	int			raw_buf_index;	/* next byte to process */
  	int			raw_buf_len;	/* total # of bytes stored */
  } CopyStateData;
  
  /* DestReceiver for COPY (query) TO */
  typedef struct
  {
  	DestReceiver pub;			/* publicly-known function pointers */
  	CopyState	cstate;			/* CopyStateData for the command */
  	uint64		processed;		/* # of tuples processed */
  } DR_copy;
  
  
  /*
   * These macros centralize code used to process line_buf and raw_buf buffers.
   * They are macros because they often do continue/break control and to avoid
   * function call overhead in tight COPY loops.
   *
   * We must use "if (1)" because the usual "do {...} while(0)" wrapper would
   * prevent the continue/break processing from working.  We end the "if (1)"
   * with "else ((void) 0)" to ensure the "if" does not unintentionally match
   * any "else" in the calling code, and to avoid any compiler warnings about
   * empty statements.  See http://www.cit.gu.edu.au/~anthony/info/C/C.macros.
   */
  
  /*
   * This keeps the character read at the top of the loop in the buffer
   * even if there is more than one read-ahead.
   */
  #define IF_NEED_REFILL_AND_NOT_EOF_CONTINUE(extralen) \
  if (1) \
  { \
  	if (raw_buf_ptr + (extralen) >= copy_buf_len && !hit_eof) \
  	{ \
  		raw_buf_ptr = prev_raw_ptr; /* undo fetch */ \
  		need_data = true; \
  		continue; \
  	} \
  } else ((void) 0)
  
  /* This consumes the remainder of the buffer and breaks */
  #define IF_NEED_REFILL_AND_EOF_BREAK(extralen) \
  if (1) \
  { \
  	if (raw_buf_ptr + (extralen) >= copy_buf_len && hit_eof) \
  	{ \
  		if (extralen) \
  			raw_buf_ptr = copy_buf_len; /* consume the partial character */ \
  		/* backslash just before EOF, treat as data char */ \
  		result = true; \
  		break; \
  	} \
  } else ((void) 0)
  
  /*
   * Transfer any approved data to line_buf; must do this to be sure
   * there is some room in raw_buf.
   */
  #define REFILL_LINEBUF \
  if (1) \
  { \
  	if (raw_buf_ptr > cstate->raw_buf_index) \
  	{ \
  		appendBinaryStringInfo(&cstate->line_buf, \
  							 cstate->raw_buf + cstate->raw_buf_index, \
  							   raw_buf_ptr - cstate->raw_buf_index); \
  		cstate->raw_buf_index = raw_buf_ptr; \
  	} \
  } else ((void) 0)
  
  /* Undo any read-ahead and jump out of the block. */
  #define NO_END_OF_COPY_GOTO \
  if (1) \
  { \
  	raw_buf_ptr = prev_raw_ptr + 1; \
  	goto not_end_of_copy; \
  } else ((void) 0)
  
  static const char BinarySignature[11] = "PGCOPY\n\377\r\n\0";
  
  
  /* non-export function prototypes */
  static CopyState BeginCopy(ParseState *pstate, bool is_from, Relation rel,
  		  RawStmt *raw_query, Oid queryRelId, List *attnamelist,
  		  List *options);
  static void EndCopy(CopyState cstate);
  static void ClosePipeToProgram(CopyState cstate);
  static CopyState BeginCopyTo(ParseState *pstate, Relation rel, RawStmt *query,
  			Oid queryRelId, const char *filename, bool is_program,
  			List *attnamelist, List *options);
  static void EndCopyTo(CopyState cstate);
  static uint64 DoCopyTo(CopyState cstate);
  static uint64 CopyTo(CopyState cstate);
  static void CopyOneRowTo(CopyState cstate, Oid tupleOid,
  			 Datum *values, bool *nulls);
  static void CopyFromInsertBatch(CopyState cstate, EState *estate,
  					CommandId mycid, int hi_options,
  					ResultRelInfo *resultRelInfo, TupleTableSlot *myslot,
  					BulkInsertState bistate,
  					int nBufferedTuples, HeapTuple *bufferedTuples,
  					uint64 firstBufferedLineNo);
  static bool CopyReadLine(CopyState cstate);
  static bool CopyReadLineText(CopyState cstate);
  static int	CopyReadAttributesText(CopyState cstate);
  static int	CopyReadAttributesCSV(CopyState cstate);
  static Datum CopyReadBinaryAttribute(CopyState cstate,
  						int column_no, FmgrInfo *flinfo,
  						Oid typioparam, int32 typmod,
  						bool *isnull);
  static void CopyAttributeOutText(CopyState cstate, char *string);
  static void CopyAttributeOutCSV(CopyState cstate, char *string,
  					bool use_quote, bool single_attr);
  static List *CopyGetAttnums(TupleDesc tupDesc, Relation rel,
  			   List *attnamelist);
  static char *limit_printout_length(const char *str);
  
  /* Low-level communications functions */
  static void SendCopyBegin(CopyState cstate);
  static void ReceiveCopyBegin(CopyState cstate);
  static void SendCopyEnd(CopyState cstate);
  static void CopySendData(CopyState cstate, const void *databuf, int datasize);
  static void CopySendString(CopyState cstate, const char *str);
  static void CopySendChar(CopyState cstate, char c);
  static void CopySendEndOfRow(CopyState cstate);
  static int CopyGetData(CopyState cstate, void *databuf,
  			int minread, int maxread);
  static void CopySendInt32(CopyState cstate, int32 val);
  static bool CopyGetInt32(CopyState cstate, int32 *val);
  static void CopySendInt16(CopyState cstate, int16 val);
  static bool CopyGetInt16(CopyState cstate, int16 *val);
  
  
  /*
   * Send copy start/stop messages for frontend copies.  These have changed
   * in past protocol redesigns.
   */
  static void
  SendCopyBegin(CopyState cstate)
  {
  	if (PG_PROTOCOL_MAJOR(FrontendProtocol) >= 3)
  	{
  		/* new way */
  		StringInfoData buf;
  		int			natts = list_length(cstate->attnumlist);
  		int16		format = (cstate->binary ? 1 : 0);
  		int			i;
  
  		pq_beginmessage(&buf, 'H');
  		pq_sendbyte(&buf, format);	/* overall format */
  		pq_sendint16(&buf, natts);
  		for (i = 0; i < natts; i++)
  			pq_sendint16(&buf, format); /* per-column formats */
  		pq_endmessage(&buf);
  		cstate->copy_dest = COPY_NEW_FE;
  	}
  	else
  	{
  		/* old way */
  		if (cstate->binary)
  			ereport(ERROR,
  					(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
  					 errmsg("COPY BINARY is not supported to stdout or from stdin")));
  		pq_putemptymessage('H');
  		/* grottiness needed for old COPY OUT protocol */
  		pq_startcopyout();
  		cstate->copy_dest = COPY_OLD_FE;
  	}
  }
  
  static void
  ReceiveCopyBegin(CopyState cstate)
  {
  	if (PG_PROTOCOL_MAJOR(FrontendProtocol) >= 3)
  	{
  		/* new way */
  		StringInfoData buf;
  		int			natts = list_length(cstate->attnumlist);
  		int16		format = (cstate->binary ? 1 : 0);
  		int			i;
  
  		pq_beginmessage(&buf, 'G');
  		pq_sendbyte(&buf, format);	/* overall format */
  		pq_sendint16(&buf, natts);
  		for (i = 0; i < natts; i++)
  			pq_sendint16(&buf, format); /* per-column formats */
  		pq_endmessage(&buf);
  		cstate->copy_dest = COPY_NEW_FE;
  		cstate->fe_msgbuf = makeStringInfo();
  	}
  	else
  	{
  		/* old way */
  		if (cstate->binary)
  			ereport(ERROR,
  					(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
  					 errmsg("COPY BINARY is not supported to stdout or from stdin")));
  		pq_putemptymessage('G');
  		/* any error in old protocol will make us lose sync */
  		pq_startmsgread();
  		cstate->copy_dest = COPY_OLD_FE;
  	}
  	/* We *must* flush here to ensure FE knows it can send. */
  	pq_flush();
  }
  
  static void
  SendCopyEnd(CopyState cstate)
  {
  	if (cstate->copy_dest == COPY_NEW_FE)
  	{
  		/* Shouldn't have any unsent data */
  		Assert(cstate->fe_msgbuf->len == 0);
  		/* Send Copy Done message */
  		pq_putemptymessage('c');
  	}
  	else
  	{
  		CopySendData(cstate, "\\.", 2);
  		/* Need to flush out the trailer (this also appends a newline) */
  		CopySendEndOfRow(cstate);
  		pq_endcopyout(false);
  	}
  }
  
  /*----------
   * CopySendData sends output data to the destination (file or frontend)
   * CopySendString does the same for null-terminated strings
   * CopySendChar does the same for single characters
   * CopySendEndOfRow does the appropriate thing at end of each data row
   *	(data is not actually flushed except by CopySendEndOfRow)
   *
   * NB: no data conversion is applied by these functions
   *----------
   */
  static void
  CopySendData(CopyState cstate, const void *databuf, int datasize)
  {
  	appendBinaryStringInfo(cstate->fe_msgbuf, databuf, datasize);
  }
  
  static void
  CopySendString(CopyState cstate, const char *str)
  {
  	appendBinaryStringInfo(cstate->fe_msgbuf, str, strlen(str));
  }
  
  static void
  CopySendChar(CopyState cstate, char c)
  {
  	appendStringInfoCharMacro(cstate->fe_msgbuf, c);
  }
  
  static void
  CopySendEndOfRow(CopyState cstate)
  {
  	StringInfo	fe_msgbuf = cstate->fe_msgbuf;
  
  	switch (cstate->copy_dest)
  	{
  		case COPY_FILE:
  			if (!cstate->binary)
  			{
  				/* Default line termination depends on platform */
  #ifndef WIN32
  				CopySendChar(cstate, '\n');
  #else
  				CopySendString(cstate, "\r\n");
  #endif
  			}
  
  			if (fwrite(fe_msgbuf->data, fe_msgbuf->len, 1,
  					   cstate->copy_file) != 1 ||
  				ferror(cstate->copy_file))
  			{
  				if (cstate->is_program)
  				{
  					if (errno == EPIPE)
  					{
  						/*
  						 * The pipe will be closed automatically on error at
  						 * the end of transaction, but we might get a better
  						 * error message from the subprocess' exit code than
  						 * just "Broken Pipe"
  						 */
  						ClosePipeToProgram(cstate);
  
  						/*
  						 * If ClosePipeToProgram() didn't throw an error, the
  						 * program terminated normally, but closed the pipe
  						 * first. Restore errno, and throw an error.
  						 */
  						errno = EPIPE;
  					}
  					ereport(ERROR,
  							(errcode_for_file_access(),
  							 errmsg("could not write to COPY program: %m")));
  				}
  				else
  					ereport(ERROR,
  							(errcode_for_file_access(),
  							 errmsg("could not write to COPY file: %m")));
  			}
  			break;
  		case COPY_OLD_FE:
  			/* The FE/BE protocol uses \n as newline for all platforms */
  			if (!cstate->binary)
  				CopySendChar(cstate, '\n');
  
  			if (pq_putbytes(fe_msgbuf->data, fe_msgbuf->len))
  			{
  				/* no hope of recovering connection sync, so FATAL */
  				ereport(FATAL,
  						(errcode(ERRCODE_CONNECTION_FAILURE),
  						 errmsg("connection lost during COPY to stdout")));
  			}
  			break;
  		case COPY_NEW_FE:
  			/* The FE/BE protocol uses \n as newline for all platforms */
  			if (!cstate->binary)
  				CopySendChar(cstate, '\n');
  
  			/* Dump the accumulated row as one CopyData message */
  			(void) pq_putmessage('d', fe_msgbuf->data, fe_msgbuf->len);
  			break;
  		case COPY_CALLBACK:
  			Assert(false);		/* Not yet supported. */
  			break;
  	}
  
  	resetStringInfo(fe_msgbuf);
  }
  
  /*
   * CopyGetData reads data from the source (file or frontend)
   *
   * We attempt to read at least minread, and at most maxread, bytes from
   * the source.  The actual number of bytes read is returned; if this is
   * less than minread, EOF was detected.
   *
   * Note: when copying from the frontend, we expect a proper EOF mark per
   * protocol; if the frontend simply drops the connection, we raise error.
   * It seems unwise to allow the COPY IN to complete normally in that case.
   *
   * NB: no data conversion is applied here.
   */
  static int
  CopyGetData(CopyState cstate, void *databuf, int minread, int maxread)
  {
  	int			bytesread = 0;
  
  	switch (cstate->copy_dest)
  	{
  		case COPY_FILE:
  			bytesread = fread(databuf, 1, maxread, cstate->copy_file);
  			if (ferror(cstate->copy_file))
  				ereport(ERROR,
  						(errcode_for_file_access(),
  						 errmsg("could not read from COPY file: %m")));
  			if (bytesread == 0)
  				cstate->reached_eof = true;
  			break;
  		case COPY_OLD_FE:
  
  			/*
  			 * We cannot read more than minread bytes (which in practice is 1)
  			 * because old protocol doesn't have any clear way of separating
  			 * the COPY stream from following data.  This is slow, but not any
  			 * slower than the code path was originally, and we don't care
  			 * much anymore about the performance of old protocol.
  			 */
  			if (pq_getbytes((char *) databuf, minread))
  			{
  				/* Only a \. terminator is legal EOF in old protocol */
  				ereport(ERROR,
  						(errcode(ERRCODE_CONNECTION_FAILURE),
  						 errmsg("unexpected EOF on client connection with an open transaction")));
  			}
  			bytesread = minread;
  			break;
  		case COPY_NEW_FE:
  			while (maxread > 0 && bytesread < minread && !cstate->reached_eof)
  			{
  				int			avail;
  
  				while (cstate->fe_msgbuf->cursor >= cstate->fe_msgbuf->len)
  				{
  					/* Try to receive another message */
  					int			mtype;
  
  			readmessage:
  					HOLD_CANCEL_INTERRUPTS();
  					pq_startmsgread();
  					mtype = pq_getbyte();
  					if (mtype == EOF)
  						ereport(ERROR,
  								(errcode(ERRCODE_CONNECTION_FAILURE),
  								 errmsg("unexpected EOF on client connection with an open transaction")));
  					if (pq_getmessage(cstate->fe_msgbuf, 0))
  						ereport(ERROR,
  								(errcode(ERRCODE_CONNECTION_FAILURE),
  								 errmsg("unexpected EOF on client connection with an open transaction")));
  					RESUME_CANCEL_INTERRUPTS();
  					switch (mtype)
  					{
  						case 'd':	/* CopyData */
  							break;
  						case 'c':	/* CopyDone */
  							/* COPY IN correctly terminated by frontend */
  							cstate->reached_eof = true;
  							return bytesread;
  						case 'f':	/* CopyFail */
  							ereport(ERROR,
  									(errcode(ERRCODE_QUERY_CANCELED),
  									 errmsg("COPY from stdin failed: %s",
  											pq_getmsgstring(cstate->fe_msgbuf))));
  							break;
  						case 'H':	/* Flush */
  						case 'S':	/* Sync */
  
  							/*
  							 * Ignore Flush/Sync for the convenience of client
  							 * libraries (such as libpq) that may send those
  							 * without noticing that the command they just
  							 * sent was COPY.
  							 */
  							goto readmessage;
  						default:
  							ereport(ERROR,
  									(errcode(ERRCODE_PROTOCOL_VIOLATION),
  									 errmsg("unexpected message type 0x%02X during COPY from stdin",
  											mtype)));
  							break;
  					}
  				}
  				avail = cstate->fe_msgbuf->len - cstate->fe_msgbuf->cursor;
  				if (avail > maxread)
  					avail = maxread;
  				pq_copymsgbytes(cstate->fe_msgbuf, databuf, avail);
  				databuf = (void *) ((char *) databuf + avail);
  				maxread -= avail;
  				bytesread += avail;
  			}
  			break;
  		case COPY_CALLBACK:
  			bytesread = cstate->data_source_cb(databuf, minread, maxread);
  			break;
  	}
  
  	return bytesread;
  }
  
  
  /*
   * These functions do apply some data conversion
   */
  
  /*
   * CopySendInt32 sends an int32 in network byte order
   */
  static void
  CopySendInt32(CopyState cstate, int32 val)
  {
  	uint32		buf;
  
  	buf = pg_hton32((uint32) val);
  	CopySendData(cstate, &buf, sizeof(buf));
  }
  
  /*
   * CopyGetInt32 reads an int32 that appears in network byte order
   *
   * Returns true if OK, false if EOF
   */
  static bool
  CopyGetInt32(CopyState cstate, int32 *val)
  {
  	uint32		buf;
  
  	if (CopyGetData(cstate, &buf, sizeof(buf), sizeof(buf)) != sizeof(buf))
  	{
  		*val = 0;				/* suppress compiler warning */
  		return false;
  	}
  	*val = (int32) pg_ntoh32(buf);
  	return true;
  }
  
  /*
   * CopySendInt16 sends an int16 in network byte order
   */
  static void
  CopySendInt16(CopyState cstate, int16 val)
  {
  	uint16		buf;
  
  	buf = pg_hton16((uint16) val);
  	CopySendData(cstate, &buf, sizeof(buf));
  }
  
  /*
   * CopyGetInt16 reads an int16 that appears in network byte order
   */
  static bool
  CopyGetInt16(CopyState cstate, int16 *val)
  {
  	uint16		buf;
  
  	if (CopyGetData(cstate, &buf, sizeof(buf), sizeof(buf)) != sizeof(buf))
  	{
  		*val = 0;				/* suppress compiler warning */
  		return false;
  	}
  	*val = (int16) pg_ntoh16(buf);
  	return true;
  }
  
  
  /*
   * CopyLoadRawBuf loads some more data into raw_buf
   *
   * Returns true if able to obtain at least one more byte, else false.
   *
   * If raw_buf_index < raw_buf_len, the unprocessed bytes are transferred
   * down to the start of the buffer and then we load more data after that.
   * This case is used only when a frontend multibyte character crosses a
   * bufferload boundary.
   */
  static bool
  CopyLoadRawBuf(CopyState cstate)
  {
  	int			nbytes;
  	int			inbytes;
  
  	if (cstate->raw_buf_index < cstate->raw_buf_len)
  	{
  		/* Copy down the unprocessed data */
  		nbytes = cstate->raw_buf_len - cstate->raw_buf_index;
  		memmove(cstate->raw_buf, cstate->raw_buf + cstate->raw_buf_index,
  				nbytes);
  	}
  	else
  		nbytes = 0;				/* no data need be saved */
  
  	inbytes = CopyGetData(cstate, cstate->raw_buf + nbytes,
  						  1, RAW_BUF_SIZE - nbytes);
  	nbytes += inbytes;
  	cstate->raw_buf[nbytes] = '\0';
  	cstate->raw_buf_index = 0;
  	cstate->raw_buf_len = nbytes;
  	return (inbytes > 0);
  }
  
  
  /*
   *	 DoCopy executes the SQL COPY statement
   *
   * Either unload or reload contents of table <relation>, depending on <from>.
   * (<from> = true means we are inserting into the table.)  In the "TO" case
   * we also support copying the output of an arbitrary SELECT, INSERT, UPDATE
   * or DELETE query.
   *
   * If <pipe> is false, transfer is between the table and the file named
   * <filename>.  Otherwise, transfer is between the table and our regular
   * input/output stream. The latter could be either stdin/stdout or a
   * socket, depending on whether we're running under Postmaster control.
   *
   * Do not allow a Postgres user without the 'pg_access_server_files' role to
   * read from or write to a file.
   *
   * Do not allow the copy if user doesn't have proper permission to access
   * the table or the specifically requested columns.
   */
  void
  DoCopy(ParseState *pstate, const CopyStmt *stmt,
  	   int stmt_location, int stmt_len,
  	   uint64 *processed)
  {
  	CopyState	cstate;
  	bool		is_from = stmt->is_from;
  	bool		pipe = (stmt->filename == NULL);
  	Relation	rel;
  	Oid			relid;
  	RawStmt    *query = NULL;
  
  	/*
  	 * Disallow COPY to/from file or program except to users with the
  	 * appropriate role.
  	 */
  	if (!pipe)
  	{
  		if (stmt->is_program)
  		{
  			if (!is_member_of_role(GetUserId(), DEFAULT_ROLE_EXECUTE_SERVER_PROGRAM))
  				ereport(ERROR,
  						(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
  						 errmsg("must be superuser or a member of the pg_execute_server_program role to COPY to or from an external program"),
  						 errhint("Anyone can COPY to stdout or from stdin. "
  								 "psql's \\copy command also works for anyone.")));
  		}
  		else
  		{
  			if (is_from && !is_member_of_role(GetUserId(), DEFAULT_ROLE_READ_SERVER_FILES))
  				ereport(ERROR,
  						(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
  						 errmsg("must be superuser or a member of the pg_read_server_files role to COPY from a file"),
  						 errhint("Anyone can COPY to stdout or from stdin. "
  								 "psql's \\copy command also works for anyone.")));
  
  			if (!is_from && !is_member_of_role(GetUserId(), DEFAULT_ROLE_WRITE_SERVER_FILES))
  				ereport(ERROR,
  						(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
  						 errmsg("must be superuser or a member of the pg_write_server_files role to COPY to a file"),
  						 errhint("Anyone can COPY to stdout or from stdin. "
  								 "psql's \\copy command also works for anyone.")));
  		}
  	}
  
  	if (stmt->relation)
  	{
  		TupleDesc	tupDesc;
  		List	   *attnums;
  		ListCell   *cur;
  		RangeTblEntry *rte;
  
  		Assert(!stmt->query);
  
  		/* Open and lock the relation, using the appropriate lock type. */
  		rel = heap_openrv(stmt->relation,
  						  (is_from ? RowExclusiveLock : AccessShareLock));
  
  		if (rel->rd_rel->relpersistence == RELPERSISTENCE_TEMP &&
  				IsYugaByteEnabled()) {
  			SetTxnWithPGRel();
  		}
  
  		relid = RelationGetRelid(rel);
  
  		rte = addRangeTableEntryForRelation(pstate, rel, NULL, false, false);
  		rte->requiredPerms = (is_from ? ACL_INSERT : ACL_SELECT);
  
  		tupDesc = RelationGetDescr(rel);
  		attnums = CopyGetAttnums(tupDesc, rel, stmt->attlist);
  		foreach(cur, attnums)
  		{
  			int			attno = lfirst_int(cur) -
  			FirstLowInvalidHeapAttributeNumber;
  
  			if (is_from)
  				rte->insertedCols = bms_add_member(rte->insertedCols, attno);
  			else
  				rte->selectedCols = bms_add_member(rte->selectedCols, attno);
  		}
  		ExecCheckRTPerms(pstate->p_rtable, true);
  
  		/*
  		 * Permission check for row security policies.
  		 *
  		 * check_enable_rls will ereport(ERROR) if the user has requested
  		 * something invalid and will otherwise indicate if we should enable
  		 * RLS (returns RLS_ENABLED) or not for this COPY statement.
  		 *
  		 * If the relation has a row security policy and we are to apply it
  		 * then perform a "query" copy and allow the normal query processing
  		 * to handle the policies.
  		 *
  		 * If RLS is not enabled for this, then just fall through to the
  		 * normal non-filtering relation handling.
  		 */
  		if (check_enable_rls(rte->relid, InvalidOid, false) == RLS_ENABLED)
  		{
  			SelectStmt *select;
  			ColumnRef  *cr;
  			ResTarget  *target;
  			RangeVar   *from;
  			List	   *targetList = NIL;
  
  			if (is_from)
  				ereport(ERROR,
  						(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
  						 errmsg("COPY FROM not supported with row-level security"),
  						 errhint("Use INSERT statements instead.")));
  
  			/*
  			 * Build target list
  			 *
  			 * If no columns are specified in the attribute list of the COPY
  			 * command, then the target list is 'all' columns. Therefore, '*'
  			 * should be used as the target list for the resulting SELECT
  			 * statement.
  			 *
  			 * In the case that columns are specified in the attribute list,
  			 * create a ColumnRef and ResTarget for each column and add them
  			 * to the target list for the resulting SELECT statement.
  			 */
  			if (!stmt->attlist)
  			{
  				cr = makeNode(ColumnRef);
  				cr->fields = list_make1(makeNode(A_Star));
  				cr->location = -1;
  
  				target = makeNode(ResTarget);
  				target->name = NULL;
  				target->indirection = NIL;
  				target->val = (Node *) cr;
  				target->location = -1;
  
  				targetList = list_make1(target);
  			}
  			else
  			{
  				ListCell   *lc;
  
  				foreach(lc, stmt->attlist)
  				{
  					/*
  					 * Build the ColumnRef for each column.  The ColumnRef
  					 * 'fields' property is a String 'Value' node (see
  					 * nodes/value.h) that corresponds to the column name
  					 * respectively.
  					 */
  					cr = makeNode(ColumnRef);
  					cr->fields = list_make1(lfirst(lc));
  					cr->location = -1;
  
  					/* Build the ResTarget and add the ColumnRef to it. */
  					target = makeNode(ResTarget);
  					target->name = NULL;
  					target->indirection = NIL;
  					target->val = (Node *) cr;
  					target->location = -1;
  
  					/* Add each column to the SELECT statement's target list */
  					targetList = lappend(targetList, target);
  				}
  			}
  
  			/*
  			 * Build RangeVar for from clause, fully qualified based on the
  			 * relation which we have opened and locked.
  			 */
  			from = makeRangeVar(get_namespace_name(RelationGetNamespace(rel)),
  								pstrdup(RelationGetRelationName(rel)),
  								-1);
  
  			/* Build query */
  			select = makeNode(SelectStmt);
  			select->targetList = targetList;
  			select->fromClause = list_make1(from);
  
  			query = makeNode(RawStmt);
  			query->stmt = (Node *) select;
  			query->stmt_location = stmt_location;
  			query->stmt_len = stmt_len;
  
  			/*
  			 * Close the relation for now, but keep the lock on it to prevent
  			 * changes between now and when we start the query-based COPY.
  			 *
  			 * We'll reopen it later as part of the query-based COPY.
  			 */
  			heap_close(rel, NoLock);
  			rel = NULL;
  		}
  	}
  	else
  	{
  		Assert(stmt->query);
  
  		query = makeNode(RawStmt);
  		query->stmt = stmt->query;
  		query->stmt_location = stmt_location;
  		query->stmt_len = stmt_len;
  
  		relid = InvalidOid;
  		rel = NULL;
  	}
  
  	if (is_from)
  	{
  		Assert(rel);
  
  		/* check read-only transaction and parallel mode */
  		if (XactReadOnly && !rel->rd_islocaltemp)
  			PreventCommandIfReadOnly("COPY FROM");
  		PreventCommandIfParallelMode("COPY FROM");
  
  		cstate = BeginCopyFrom(pstate, rel, stmt->filename, stmt->is_program,
  							   NULL, stmt->attlist, stmt->options);
  		*processed = CopyFrom(cstate);	/* copy from file to database */
  		EndCopyFrom(cstate);
  	}
  	else
  	{
  		cstate = BeginCopyTo(pstate, rel, query, relid,
  							 stmt->filename, stmt->is_program,
  							 stmt->attlist, stmt->options);
  		*processed = DoCopyTo(cstate);	/* copy from database to file */
  		EndCopyTo(cstate);
  	}
  
  	/*
  	 * Close the relation. If reading, we can release the AccessShareLock we
  	 * got; if writing, we should hold the lock until end of transaction to
  	 * ensure that updates will be committed before lock is released.
  	 */
  	if (rel != NULL)
  		heap_close(rel, (is_from ? NoLock : AccessShareLock));
  }
  
  /*
   * Process the statement option list for COPY.
   *
   * Scan the options list (a list of DefElem) and transpose the information
   * into cstate, applying appropriate error checking.
   *
   * cstate is assumed to be filled with zeroes initially.
   *
   * This is exported so that external users of the COPY API can sanity-check
   * a list of options.  In that usage, cstate should be passed as NULL
   * (since external users don't know sizeof(CopyStateData)) and the collected
   * data is just leaked until CurrentMemoryContext is reset.
   *
   * Note that additional checking, such as whether column names listed in FORCE
   * QUOTE actually exist, has to be applied later.  This just checks for
   * self-consistency of the options list.
   */
  void
  ProcessCopyOptions(ParseState *pstate,
  				   CopyState cstate,
  				   bool is_from,
  				   List *options)
  {
  	bool		format_specified = false;
  	ListCell   *option;
  
  	/* Support external use for option sanity checking */
  	if (cstate == NULL)
  		cstate = (CopyStateData *) palloc0(sizeof(CopyStateData));
  
  	cstate->is_copy_from = is_from;
  
  	cstate->file_encoding = -1;
  
  	/* Extract options from the statement node tree */
  	foreach(option, options)
  	{
  		DefElem    *defel = lfirst_node(DefElem, option);
  
  		if (strcmp(defel->defname, "format") == 0)
  		{
  			char	   *fmt = defGetString(defel);
  
  			if (format_specified)
  				ereport(ERROR,
  						(errcode(ERRCODE_SYNTAX_ERROR),
  						 errmsg("conflicting or redundant options"),
  						 parser_errposition(pstate, defel->location)));
  			format_specified = true;
  			if (strcmp(fmt, "text") == 0)
  				 /* default format */ ;
  			else if (strcmp(fmt, "csv") == 0)
  				cstate->csv_mode = true;
  			else if (strcmp(fmt, "binary") == 0)
  				cstate->binary = true;
  			else
  				ereport(ERROR,
  						(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
  						 errmsg("COPY format \"%s\" not recognized", fmt),
  						 parser_errposition(pstate, defel->location)));
  		}
  		else if (strcmp(defel->defname, "oids") == 0)
  		{
  			if (cstate->oids)
  				ereport(ERROR,
  						(errcode(ERRCODE_SYNTAX_ERROR),
  						 errmsg("conflicting or redundant options"),
  						 parser_errposition(pstate, defel->location)));
  			cstate->oids = defGetBoolean(defel);
  		}
  		else if (strcmp(defel->defname, "freeze") == 0)
  		{
  			if (cstate->freeze)
  				ereport(ERROR,
  						(errcode(ERRCODE_SYNTAX_ERROR),
  						 errmsg("conflicting or redundant options"),
  						 parser_errposition(pstate, defel->location)));
  			cstate->freeze = defGetBoolean(defel);
  		}
  		else if (strcmp(defel->defname, "delimiter") == 0)
  		{
  			if (cstate->delim)
  				ereport(ERROR,
  						(errcode(ERRCODE_SYNTAX_ERROR),
  						 errmsg("conflicting or redundant options"),
  						 parser_errposition(pstate, defel->location)));
  			cstate->delim = defGetString(defel);
  		}
  		else if (strcmp(defel->defname, "null") == 0)
  		{
  			if (cstate->null_print)
  				ereport(ERROR,
  						(errcode(ERRCODE_SYNTAX_ERROR),
  						 errmsg("conflicting or redundant options"),
  						 parser_errposition(pstate, defel->location)));
  			cstate->null_print = defGetString(defel);
  		}
  		else if (strcmp(defel->defname, "header") == 0)
  		{
  			if (cstate->header_line)
  				ereport(ERROR,
  						(errcode(ERRCODE_SYNTAX_ERROR),
  						 errmsg("conflicting or redundant options"),
  						 parser_errposition(pstate, defel->location)));
  			cstate->header_line = defGetBoolean(defel);
  		}
  		else if (strcmp(defel->defname, "quote") == 0)
  		{
  			if (cstate->quote)
  				ereport(ERROR,
  						(errcode(ERRCODE_SYNTAX_ERROR),
  						 errmsg("conflicting or redundant options"),
  						 parser_errposition(pstate, defel->location)));
  			cstate->quote = defGetString(defel);
  		}
  		else if (strcmp(defel->defname, "escape") == 0)
  		{
  			if (cstate->escape)
  				ereport(ERROR,
  						(errcode(ERRCODE_SYNTAX_ERROR),
  						 errmsg("conflicting or redundant options"),
  						 parser_errposition(pstate, defel->location)));
  			cstate->escape = defGetString(defel);
  		}
  		else if (strcmp(defel->defname, "force_quote") == 0)
  		{
  			if (cstate->force_quote || cstate->force_quote_all)
  				ereport(ERROR,
  						(errcode(ERRCODE_SYNTAX_ERROR),
  						 errmsg("conflicting or redundant options"),
  						 parser_errposition(pstate, defel->location)));
  			if (defel->arg && IsA(defel->arg, A_Star))
  				cstate->force_quote_all = true;
  			else if (defel->arg && IsA(defel->arg, List))
  				cstate->force_quote = castNode(List, defel->arg);
  			else
  				ereport(ERROR,
  						(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
  						 errmsg("argument to option \"%s\" must be a list of column names",
  								defel->defname),
  						 parser_errposition(pstate, defel->location)));
  		}
  		else if (strcmp(defel->defname, "force_not_null") == 0)
  		{
  			if (cstate->force_notnull)
  				ereport(ERROR,
  						(errcode(ERRCODE_SYNTAX_ERROR),
  						 errmsg("conflicting or redundant options"),
  						 parser_errposition(pstate, defel->location)));
  			if (defel->arg && IsA(defel->arg, List))
  				cstate->force_notnull = castNode(List, defel->arg);
  			else
  				ereport(ERROR,
  						(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
  						 errmsg("argument to option \"%s\" must be a list of column names",
  								defel->defname),
  						 parser_errposition(pstate, defel->location)));
  		}
  		else if (strcmp(defel->defname, "force_null") == 0)
  		{
  			if (cstate->force_null)
  				ereport(ERROR,
  						(errcode(ERRCODE_SYNTAX_ERROR),
  						 errmsg("conflicting or redundant options")));
  			if (defel->arg && IsA(defel->arg, List))
  				cstate->force_null = castNode(List, defel->arg);
  			else
  				ereport(ERROR,
  						(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
  						 errmsg("argument to option \"%s\" must be a list of column names",
  								defel->defname),
  						 parser_errposition(pstate, defel->location)));
  		}
  		else if (strcmp(defel->defname, "convert_selectively") == 0)
  		{
  			/*
  			 * Undocumented, not-accessible-from-SQL option: convert only the
  			 * named columns to binary form, storing the rest as NULLs. It's
  			 * allowed for the column list to be NIL.
  			 */
  			if (cstate->convert_selectively)
  				ereport(ERROR,
  						(errcode(ERRCODE_SYNTAX_ERROR),
  						 errmsg("conflicting or redundant options"),
  						 parser_errposition(pstate, defel->location)));
  			cstate->convert_selectively = true;
  			if (defel->arg == NULL || IsA(defel->arg, List))
  				cstate->convert_select = castNode(List, defel->arg);
  			else
  				ereport(ERROR,
  						(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
  						 errmsg("argument to option \"%s\" must be a list of column names",
  								defel->defname),
  						 parser_errposition(pstate, defel->location)));
  		}
  		else if (strcmp(defel->defname, "encoding") == 0)
  		{
  			if (cstate->file_encoding >= 0)
  				ereport(ERROR,
  						(errcode(ERRCODE_SYNTAX_ERROR),
  						 errmsg("conflicting or redundant options"),
  						 parser_errposition(pstate, defel->location)));
  			cstate->file_encoding = pg_char_to_encoding(defGetString(defel));
  			if (cstate->file_encoding < 0)
  				ereport(ERROR,
  						(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
  						 errmsg("argument to option \"%s\" must be a valid encoding name",
  								defel->defname),
  						 parser_errposition(pstate, defel->location)));
  		}
  		else
  			ereport(ERROR,
  					(errcode(ERRCODE_SYNTAX_ERROR),
  					 errmsg("option \"%s\" not recognized",
  							defel->defname),
  					 parser_errposition(pstate, defel->location)));
  	}
  
  	/*
  	 * Check for incompatible options (must do these two before inserting
  	 * defaults)
  	 */
  	if (cstate->binary && cstate->delim)
  		ereport(ERROR,
  				(errcode(ERRCODE_SYNTAX_ERROR),
  				 errmsg("cannot specify DELIMITER in BINARY mode")));
  
  	if (cstate->binary && cstate->null_print)
  		ereport(ERROR,
  				(errcode(ERRCODE_SYNTAX_ERROR),
  				 errmsg("cannot specify NULL in BINARY mode")));
  
  	/* Set defaults for omitted options */
  	if (!cstate->delim)
  		cstate->delim = cstate->csv_mode ? "," : "\t";
  
  	if (!cstate->null_print)
  		cstate->null_print = cstate->csv_mode ? "" : "\\N";
  	cstate->null_print_len = strlen(cstate->null_print);
  
  	if (cstate->csv_mode)
  	{
  		if (!cstate->quote)
  			cstate->quote = "\"";
  		if (!cstate->escape)
  			cstate->escape = cstate->quote;
  	}
  
  	/* Only single-byte delimiter strings are supported. */
  	if (strlen(cstate->delim) != 1)
  		ereport(ERROR,
  				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
  				 errmsg("COPY delimiter must be a single one-byte character")));
  
  	/* Disallow end-of-line characters */
  	if (strchr(cstate->delim, '\r') != NULL ||
  		strchr(cstate->delim, '\n') != NULL)
  		ereport(ERROR,
  				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
  				 errmsg("COPY delimiter cannot be newline or carriage return")));
  
  	if (strchr(cstate->null_print, '\r') != NULL ||
  		strchr(cstate->null_print, '\n') != NULL)
  		ereport(ERROR,
  				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
  				 errmsg("COPY null representation cannot use newline or carriage return")));
  
  	/*
  	 * Disallow unsafe delimiter characters in non-CSV mode.  We can't allow
  	 * backslash because it would be ambiguous.  We can't allow the other
  	 * cases because data characters matching the delimiter must be
  	 * backslashed, and certain backslash combinations are interpreted
  	 * non-literally by COPY IN.  Disallowing all lower case ASCII letters is
  	 * more than strictly necessary, but seems best for consistency and
  	 * future-proofing.  Likewise we disallow all digits though only octal
  	 * digits are actually dangerous.
  	 */
  	if (!cstate->csv_mode &&
  		strchr("\\.abcdefghijklmnopqrstuvwxyz0123456789",
  			   cstate->delim[0]) != NULL)
  		ereport(ERROR,
  				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
  				 errmsg("COPY delimiter cannot be \"%s\"", cstate->delim)));
  
  	/* Check header */
  	if (!cstate->csv_mode && cstate->header_line)
  		ereport(ERROR,
  				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
  				 errmsg("COPY HEADER available only in CSV mode")));
  
  	/* Check quote */
  	if (!cstate->csv_mode && cstate->quote != NULL)
  		ereport(ERROR,
  				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
  				 errmsg("COPY quote available only in CSV mode")));
  
  	if (cstate->csv_mode && strlen(cstate->quote) != 1)
  		ereport(ERROR,
  				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
  				 errmsg("COPY quote must be a single one-byte character")));
  
  	if (cstate->csv_mode && cstate->delim[0] == cstate->quote[0])
  		ereport(ERROR,
  				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
  				 errmsg("COPY delimiter and quote must be different")));
  
  	/* Check escape */
  	if (!cstate->csv_mode && cstate->escape != NULL)
  		ereport(ERROR,
  				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
  				 errmsg("COPY escape available only in CSV mode")));
  
  	if (cstate->csv_mode && strlen(cstate->escape) != 1)
  		ereport(ERROR,
  				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
  				 errmsg("COPY escape must be a single one-byte character")));
  
  	/* Check force_quote */
  	if (!cstate->csv_mode && (cstate->force_quote || cstate->force_quote_all))
  		ereport(ERROR,
  				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
  				 errmsg("COPY force quote available only in CSV mode")));
  	if ((cstate->force_quote || cstate->force_quote_all) && is_from)
  		ereport(ERROR,
  				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
  				 errmsg("COPY force quote only available using COPY TO")));
  
  	/* Check force_notnull */
  	if (!cstate->csv_mode && cstate->force_notnull != NIL)
  		ereport(ERROR,
  				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
  				 errmsg("COPY force not null available only in CSV mode")));
  	if (cstate->force_notnull != NIL && !is_from)
  		ereport(ERROR,
  				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
  				 errmsg("COPY force not null only available using COPY FROM")));
  
  	/* Check force_null */
  	if (!cstate->csv_mode && cstate->force_null != NIL)
  		ereport(ERROR,
  				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
  				 errmsg("COPY force null available only in CSV mode")));
  
  	if (cstate->force_null != NIL && !is_from)
  		ereport(ERROR,
  				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
  				 errmsg("COPY force null only available using COPY FROM")));
  
  	/* Don't allow the delimiter to appear in the null string. */
  	if (strchr(cstate->null_print, cstate->delim[0]) != NULL)
  		ereport(ERROR,
  				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
  				 errmsg("COPY delimiter must not appear in the NULL specification")));
  
  	/* Don't allow the CSV quote char to appear in the null string. */
  	if (cstate->csv_mode &&
  		strchr(cstate->null_print, cstate->quote[0]) != NULL)
  		ereport(ERROR,
  				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
  				 errmsg("CSV quote character must not appear in the NULL specification")));
  }
  
  /*
   * Common setup routines used by BeginCopyFrom and BeginCopyTo.
   *
   * Iff <binary>, unload or reload in the binary format, as opposed to the
   * more wasteful but more robust and portable text format.
   *
   * Iff <oids>, unload or reload the format that includes OID information.
   * On input, we accept OIDs whether or not the table has an OID column,
   * but silently drop them if it does not.  On output, we report an error
   * if the user asks for OIDs in a table that has none (not providing an
   * OID column might seem friendlier, but could seriously confuse programs).
   *
   * If in the text format, delimit columns with delimiter <delim> and print
   * NULL values as <null_print>.
   */
  static CopyState
  BeginCopy(ParseState *pstate,
  		  bool is_from,
  		  Relation rel,
  		  RawStmt *raw_query,
  		  Oid queryRelId,
  		  List *attnamelist,
  		  List *options)
  {
  	CopyState	cstate;
  	TupleDesc	tupDesc;
  	int			num_phys_attrs;
  	MemoryContext oldcontext;
  
  	/* Allocate workspace and zero all fields */
  	cstate = (CopyStateData *) palloc0(sizeof(CopyStateData));
  
  	/*
  	 * We allocate everything used by a cstate in a new memory context. This
  	 * avoids memory leaks during repeated use of COPY in a query.
  	 */
  	cstate->copycontext = AllocSetContextCreate(CurrentMemoryContext,
  												"COPY",
  												ALLOCSET_DEFAULT_SIZES);
  
  	oldcontext = MemoryContextSwitchTo(cstate->copycontext);
  
  	/* Extract options from the statement node tree */
  	ProcessCopyOptions(pstate, cstate, is_from, options);
  
  	/* Process the source/target relation or query */
  	if (rel)
  	{
  		Assert(!raw_query);
  
  		cstate->rel = rel;
  
  		tupDesc = RelationGetDescr(cstate->rel);
  
  		/* Don't allow COPY w/ OIDs to or from a table without them */
  		if (cstate->oids && !cstate->rel->rd_rel->relhasoids)
  			ereport(ERROR,
  					(errcode(ERRCODE_UNDEFINED_COLUMN),
  					 errmsg("table \"%s\" does not have OIDs",
  							RelationGetRelationName(cstate->rel))));
  	}
  	else
  	{
  		List	   *rewritten;
  		Query	   *query;
  		PlannedStmt *plan;
  		DestReceiver *dest;
  
  		Assert(!is_from);
  		cstate->rel = NULL;
  
  		/* Don't allow COPY w/ OIDs from a query */
  		if (cstate->oids)
  			ereport(ERROR,
  					(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
  					 errmsg("COPY (query) WITH OIDS is not supported")));
  
  		/*
  		 * Run parse analysis and rewrite.  Note this also acquires sufficient
  		 * locks on the source table(s).
  		 *
  		 * Because the parser and planner tend to scribble on their input, we
  		 * make a preliminary copy of the source querytree.  This prevents
  		 * problems in the case that the COPY is in a portal or plpgsql
  		 * function and is executed repeatedly.  (See also the same hack in
  		 * DECLARE CURSOR and PREPARE.)  XXX FIXME someday.
  		 */
  		rewritten = pg_analyze_and_rewrite(copyObject(raw_query),
  										   pstate->p_sourcetext, NULL, 0,
  										   NULL);
  
  		/* check that we got back something we can work with */
  		if (rewritten == NIL)
  		{
  			ereport(ERROR,
  					(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
  					 errmsg("DO INSTEAD NOTHING rules are not supported for COPY")));
  		}
  		else if (list_length(rewritten) > 1)
  		{
  			ListCell   *lc;
  
  			/* examine queries to determine which error message to issue */
  			foreach(lc, rewritten)
  			{
  				Query	   *q = lfirst_node(Query, lc);
  
  				if (q->querySource == QSRC_QUAL_INSTEAD_RULE)
  					ereport(ERROR,
  							(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
  							 errmsg("conditional DO INSTEAD rules are not supported for COPY")));
  				if (q->querySource == QSRC_NON_INSTEAD_RULE)
  					ereport(ERROR,
  							(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
  							 errmsg("DO ALSO rules are not supported for the COPY")));
  			}
  
  			ereport(ERROR,
  					(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
  					 errmsg("multi-statement DO INSTEAD rules are not supported for COPY")));
  		}
  
  		query = linitial_node(Query, rewritten);
  
  		/* The grammar allows SELECT INTO, but we don't support that */
  		if (query->utilityStmt != NULL &&
  			IsA(query->utilityStmt, CreateTableAsStmt))
  			ereport(ERROR,
  					(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
  					 errmsg("COPY (SELECT INTO) is not supported")));
  
  		Assert(query->utilityStmt == NULL);
  
  		/*
  		 * Similarly the grammar doesn't enforce the presence of a RETURNING
  		 * clause, but this is required here.
  		 */
  		if (query->commandType != CMD_SELECT &&
  			query->returningList == NIL)
  		{
  			Assert(query->commandType == CMD_INSERT ||
  				   query->commandType == CMD_UPDATE ||
  				   query->commandType == CMD_DELETE);
  
  			ereport(ERROR,
  					(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
  					 errmsg("COPY query must have a RETURNING clause")));
  		}
  
  		/* plan the query */
  		plan = pg_plan_query(query, CURSOR_OPT_PARALLEL_OK, NULL);
  
  		/*
  		 * With row level security and a user using "COPY relation TO", we
  		 * have to convert the "COPY relation TO" to a query-based COPY (eg:
  		 * "COPY (SELECT * FROM relation) TO"), to allow the rewriter to add
  		 * in any RLS clauses.
  		 *
  		 * When this happens, we are passed in the relid of the originally
  		 * found relation (which we have locked).  As the planner will look up
  		 * the relation again, we double-check here to make sure it found the
  		 * same one that we have locked.
  		 */
  		if (queryRelId != InvalidOid)
  		{
  			/*
  			 * Note that with RLS involved there may be multiple relations,
  			 * and while the one we need is almost certainly first, we don't
  			 * make any guarantees of that in the planner, so check the whole
  			 * list and make sure we find the original relation.
  			 */
  			if (!list_member_oid(plan->relationOids, queryRelId))
  				ereport(ERROR,
  						(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
  						 errmsg("relation referenced by COPY statement has changed")));
  		}
  
  		/*
  		 * Use a snapshot with an updated command ID to ensure this query sees
  		 * results of any previously executed queries.
  		 */
  		PushCopiedSnapshot(GetActiveSnapshot());
  		UpdateActiveSnapshotCommandId();
  
  		/* Create dest receiver for COPY OUT */
  		dest = CreateDestReceiver(DestCopyOut);
  		((DR_copy *) dest)->cstate = cstate;
  
  		/* Create a QueryDesc requesting no output */
  		cstate->queryDesc = CreateQueryDesc(plan, pstate->p_sourcetext,
  											GetActiveSnapshot(),
  											InvalidSnapshot,
  											dest, NULL, NULL, 0);
  
  		/*
  		 * Call ExecutorStart to prepare the plan for execution.
  		 *
  		 * ExecutorStart computes a result tupdesc for us
  		 */
  		ExecutorStart(cstate->queryDesc, 0);
  
  		tupDesc = cstate->queryDesc->tupDesc;
  	}
  
  	/* Generate or convert list of attributes to process */
  	cstate->attnumlist = CopyGetAttnums(tupDesc, cstate->rel, attnamelist);
  
  	num_phys_attrs = tupDesc->natts;
  
  	/* Convert FORCE_QUOTE name list to per-column flags, check validity */
  	cstate->force_quote_flags = (bool *) palloc0(num_phys_attrs * sizeof(bool));
  	if (cstate->force_quote_all)
  	{
  		int			i;
  
  		for (i = 0; i < num_phys_attrs; i++)
  			cstate->force_quote_flags[i] = true;
  	}
  	else if (cstate->force_quote)
  	{
  		List	   *attnums;
  		ListCell   *cur;
  
  		attnums = CopyGetAttnums(tupDesc, cstate->rel, cstate->force_quote);
  
  		foreach(cur, attnums)
  		{
  			int			attnum = lfirst_int(cur);
  			Form_pg_attribute attr = TupleDescAttr(tupDesc, attnum - 1);
  
  			if (!list_member_int(cstate->attnumlist, attnum))
  				ereport(ERROR,
  						(errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
  						 errmsg("FORCE_QUOTE column \"%s\" not referenced by COPY",
  								NameStr(attr->attname))));
  			cstate->force_quote_flags[attnum - 1] = true;
  		}
  	}
  
  	/* Convert FORCE_NOT_NULL name list to per-column flags, check validity */
  	cstate->force_notnull_flags = (bool *) palloc0(num_phys_attrs * sizeof(bool));
  	if (cstate->force_notnull)
  	{
  		List	   *attnums;
  		ListCell   *cur;
  
  		attnums = CopyGetAttnums(tupDesc, cstate->rel, cstate->force_notnull);
  
  		foreach(cur, attnums)
  		{
  			int			attnum = lfirst_int(cur);
  			Form_pg_attribute attr = TupleDescAttr(tupDesc, attnum - 1);
  
  			if (!list_member_int(cstate->attnumlist, attnum))
  				ereport(ERROR,
  						(errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
  						 errmsg("FORCE_NOT_NULL column \"%s\" not referenced by COPY",
  								NameStr(attr->attname))));
  			cstate->force_notnull_flags[attnum - 1] = true;
  		}
  	}
  
  	/* Convert FORCE_NULL name list to per-column flags, check validity */
  	cstate->force_null_flags = (bool *) palloc0(num_phys_attrs * sizeof(bool));
  	if (cstate->force_null)
  	{
  		List	   *attnums;
  		ListCell   *cur;
  
  		attnums = CopyGetAttnums(tupDesc, cstate->rel, cstate->force_null);
  
  		foreach(cur, attnums)
  		{
  			int			attnum = lfirst_int(cur);
  			Form_pg_attribute attr = TupleDescAttr(tupDesc, attnum - 1);
  
  			if (!list_member_int(cstate->attnumlist, attnum))
  				ereport(ERROR,
  						(errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
  						 errmsg("FORCE_NULL column \"%s\" not referenced by COPY",
  								NameStr(attr->attname))));
  			cstate->force_null_flags[attnum - 1] = true;
  		}
  	}
  
  	/* Convert convert_selectively name list to per-column flags */
  	if (cstate->convert_selectively)
  	{
  		List	   *attnums;
  		ListCell   *cur;
  
  		cstate->convert_select_flags = (bool *) palloc0(num_phys_attrs * sizeof(bool));
  
  		attnums = CopyGetAttnums(tupDesc, cstate->rel, cstate->convert_select);
  
  		foreach(cur, attnums)
  		{
  			int			attnum = lfirst_int(cur);
  			Form_pg_attribute attr = TupleDescAttr(tupDesc, attnum - 1);
  
  			if (!list_member_int(cstate->attnumlist, attnum))
  				ereport(ERROR,
  						(errcode(ERRCODE_INVALID_COLUMN_REFERENCE),
  						 errmsg_internal("selected column \"%s\" not referenced by COPY",
  										 NameStr(attr->attname))));
  			cstate->convert_select_flags[attnum - 1] = true;
  		}
  	}
  
  	/* Use client encoding when ENCODING option is not specified. */
  	if (cstate->file_encoding < 0)
  		cstate->file_encoding = pg_get_client_encoding();
  
  	/*
  	 * Set up encoding conversion info.  Even if the file and server encodings
  	 * are the same, we must apply pg_any_to_server() to validate data in
  	 * multibyte encodings.
  	 */
  	cstate->need_transcoding =
  		(cstate->file_encoding != GetDatabaseEncoding() ||
  		 pg_database_encoding_max_length() > 1);
  	/* See Multibyte encoding comment above */
  	cstate->encoding_embeds_ascii = PG_ENCODING_IS_CLIENT_ONLY(cstate->file_encoding);
  
  	cstate->copy_dest = COPY_FILE;	/* default */
  
  	MemoryContextSwitchTo(oldcontext);
  
  	return cstate;
  }
  
  /*
   * Closes the pipe to an external program, checking the pclose() return code.
   */
  static void
  ClosePipeToProgram(CopyState cstate)
  {
  	int			pclose_rc;
  
  	Assert(cstate->is_program);
  
  	pclose_rc = ClosePipeStream(cstate->copy_file);
  	if (pclose_rc == -1)
  		ereport(ERROR,
  				(errcode_for_file_access(),
  				 errmsg("could not close pipe to external command: %m")));
  	else if (pclose_rc != 0)
  	{
  		/*
  		 * If we ended a COPY FROM PROGRAM before reaching EOF, then it's
  		 * expectable for the called program to fail with SIGPIPE, and we
  		 * should not report that as an error.  Otherwise, SIGPIPE indicates a
  		 * problem.
  		 */
  		if (cstate->is_copy_from && !cstate->reached_eof &&
  			wait_result_is_signal(pclose_rc, SIGPIPE))
  			return;
  
  		ereport(ERROR,
  				(errcode(ERRCODE_EXTERNAL_ROUTINE_EXCEPTION),
  				 errmsg("program \"%s\" failed",
  						cstate->filename),
  				 errdetail_internal("%s", wait_result_to_str(pclose_rc))));
  	}
  }
  
  /*
   * Release resources allocated in a cstate for COPY TO/FROM.
   */
  static void
  EndCopy(CopyState cstate)
  {
  	if (cstate->is_program)
  	{
  		ClosePipeToProgram(cstate);
  	}
  	else
  	{
  		if (cstate->filename != NULL && FreeFile(cstate->copy_file))
  			ereport(ERROR,
  					(errcode_for_file_access(),
  					 errmsg("could not close file \"%s\": %m",
  							cstate->filename)));
  	}
  
  	MemoryContextDelete(cstate->copycontext);
  	pfree(cstate);
  }
  
  /*
   * Setup CopyState to read tuples from a table or a query for COPY TO.
   */
  static CopyState
  BeginCopyTo(ParseState *pstate,
  			Relation rel,
  			RawStmt *query,
  			Oid queryRelId,
  			const char *filename,
  			bool is_program,
  			List *attnamelist,
  			List *options)
  {
  	CopyState	cstate;
  	bool		pipe = (filename == NULL);
  	MemoryContext oldcontext;
  
  	if (rel != NULL && rel->rd_rel->relkind != RELKIND_RELATION)
  	{
  		if (rel->rd_rel->relkind == RELKIND_VIEW)
  			ereport(ERROR,
  					(errcode(ERRCODE_WRONG_OBJECT_TYPE),
  					 errmsg("cannot copy from view \"%s\"",
  							RelationGetRelationName(rel)),
  					 errhint("Try the COPY (SELECT ...) TO variant.")));
  		else if (rel->rd_rel->relkind == RELKIND_MATVIEW)
  			ereport(ERROR,
  					(errcode(ERRCODE_WRONG_OBJECT_TYPE),
  					 errmsg("cannot copy from materialized view \"%s\"",
  							RelationGetRelationName(rel)),
  					 errhint("Try the COPY (SELECT ...) TO variant.")));
  		else if (rel->rd_rel->relkind == RELKIND_FOREIGN_TABLE)
  			ereport(ERROR,
  					(errcode(ERRCODE_WRONG_OBJECT_TYPE),
  					 errmsg("cannot copy from foreign table \"%s\"",
  							RelationGetRelationName(rel)),
  					 errhint("Try the COPY (SELECT ...) TO variant.")));
  		else if (rel->rd_rel->relkind == RELKIND_SEQUENCE)
  			ereport(ERROR,
  					(errcode(ERRCODE_WRONG_OBJECT_TYPE),
  					 errmsg("cannot copy from sequence \"%s\"",
  							RelationGetRelationName(rel))));
  		else if (rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
  			ereport(ERROR,
  					(errcode(ERRCODE_WRONG_OBJECT_TYPE),
  					 errmsg("cannot copy from partitioned table \"%s\"",
  							RelationGetRelationName(rel)),
  					 errhint("Try the COPY (SELECT ...) TO variant.")));
  		else
  			ereport(ERROR,
  					(errcode(ERRCODE_WRONG_OBJECT_TYPE),
  					 errmsg("cannot copy from non-table relation \"%s\"",
  							RelationGetRelationName(rel))));
  	}
  
  	cstate = BeginCopy(pstate, false, rel, query, queryRelId, attnamelist,
  					   options);
  	oldcontext = MemoryContextSwitchTo(cstate->copycontext);
  
  	if (pipe)
  	{
  		Assert(!is_program);	/* the grammar does not allow this */
  		if (whereToSendOutput != DestRemote)
  			cstate->copy_file = stdout;
  	}
  	else
  	{
  		cstate->filename = pstrdup(filename);
  		cstate->is_program = is_program;
  
  		if (is_program)
  		{
  			cstate->copy_file = OpenPipeStream(cstate->filename, PG_BINARY_W);
  			if (cstate->copy_file == NULL)
  				ereport(ERROR,
  						(errcode_for_file_access(),
  						 errmsg("could not execute command \"%s\": %m",
  								cstate->filename)));
  		}
  		else
  		{
  			mode_t		oumask; /* Pre-existing umask value */
  			struct stat st;
  
  			/*
  			 * Prevent write to relative path ... too easy to shoot oneself in
  			 * the foot by overwriting a database file ...
  			 */
  			if (!is_absolute_path(filename))
  				ereport(ERROR,
  						(errcode(ERRCODE_INVALID_NAME),
  						 errmsg("relative path not allowed for COPY to file")));
  
  			oumask = umask(S_IWGRP | S_IWOTH);
  			PG_TRY();
  			{
  				cstate->copy_file = AllocateFile(cstate->filename, PG_BINARY_W);
  			}
  			PG_CATCH();
  			{
  				umask(oumask);
  				PG_RE_THROW();
  			}
  			PG_END_TRY();
  			umask(oumask);
  			if (cstate->copy_file == NULL)
  			{
  				/* copy errno because ereport subfunctions might change it */
  				int			save_errno = errno;
  
  				ereport(ERROR,
  						(errcode_for_file_access(),
  						 errmsg("could not open file \"%s\" for writing: %m",
  								cstate->filename),
  						 (save_errno == ENOENT || save_errno == EACCES) ?
  						 errhint("COPY TO instructs the PostgreSQL server process to write a file. "
  								 "You may want a client-side facility such as psql's \\copy.") : 0));
  			}
  
  			if (fstat(fileno(cstate->copy_file), &st))
  				ereport(ERROR,
  						(errcode_for_file_access(),
  						 errmsg("could not stat file \"%s\": %m",
  								cstate->filename)));
  
  			if (S_ISDIR(st.st_mode))
  				ereport(ERROR,
  						(errcode(ERRCODE_WRONG_OBJECT_TYPE),
  						 errmsg("\"%s\" is a directory", cstate->filename)));
  		}
  	}
  
  	MemoryContextSwitchTo(oldcontext);
  
  	return cstate;
  }
  
  /*
   * This intermediate routine exists mainly to localize the effects of setjmp
   * so we don't need to plaster a lot of variables with "volatile".
   */
  static uint64
  DoCopyTo(CopyState cstate)
  {
  	bool		pipe = (cstate->filename == NULL);
  	bool		fe_copy = (pipe && whereToSendOutput == DestRemote);
  	uint64		processed;
  
  	PG_TRY();
  	{
  		if (fe_copy)
  			SendCopyBegin(cstate);
  
  		processed = CopyTo(cstate);
  
  		if (fe_copy)
  			SendCopyEnd(cstate);
  	}
  	PG_CATCH();
  	{
  		/*
  		 * Make sure we turn off old-style COPY OUT mode upon error. It is
  		 * okay to do this in all cases, since it does nothing if the mode is
  		 * not on.
  		 */
  		pq_endcopyout(true);
  		PG_RE_THROW();
  	}
  	PG_END_TRY();
  
  	return processed;
  }
  
  /*
   * Clean up storage and release resources for COPY TO.
   */
  static void
  EndCopyTo(CopyState cstate)
  {
  	if (cstate->queryDesc != NULL)
  	{
  		/* Close down the query and free resources. */
  		ExecutorFinish(cstate->queryDesc);
  		ExecutorEnd(cstate->queryDesc);
  		FreeQueryDesc(cstate->queryDesc);
  		PopActiveSnapshot();
  	}
  
  	/* Clean up storage */
  	EndCopy(cstate);
  }
  
  /*
   * Copy from relation or query TO file.
   */
  static uint64
  CopyTo(CopyState cstate)
  {
  	TupleDesc	tupDesc;
  	int			num_phys_attrs;
  	ListCell   *cur;
  	uint64		processed;
  
  	if (cstate->rel)
  		tupDesc = RelationGetDescr(cstate->rel);
  	else
  		tupDesc = cstate->queryDesc->tupDesc;
  	num_phys_attrs = tupDesc->natts;
  	cstate->null_print_client = cstate->null_print; /* default */
  
  	/* We use fe_msgbuf as a per-row buffer regardless of copy_dest */
  	cstate->fe_msgbuf = makeStringInfo();
  
  	/* Get info about the columns we need to process. */
  	cstate->out_functions = (FmgrInfo *) palloc(num_phys_attrs * sizeof(FmgrInfo));
  	foreach(cur, cstate->attnumlist)
  	{
  		int			attnum = lfirst_int(cur);
  		Oid			out_func_oid;
  		bool		isvarlena;
  		Form_pg_attribute attr = TupleDescAttr(tupDesc, attnum - 1);
  
  		if (cstate->binary)
  			getTypeBinaryOutputInfo(attr->atttypid,
  									&out_func_oid,
  									&isvarlena);
  		else
  			getTypeOutputInfo(attr->atttypid,
  							  &out_func_oid,
  							  &isvarlena);
  		fmgr_info(out_func_oid, &cstate->out_functions[attnum - 1]);
  	}
  
  	/*
  	 * Create a temporary memory context that we can reset once per row to
  	 * recover palloc'd memory.  This avoids any problems with leaks inside
  	 * datatype output routines, and should be faster than retail pfree's
  	 * anyway.  (We don't need a whole econtext as CopyFrom does.)
  	 */
  	cstate->rowcontext = AllocSetContextCreate(CurrentMemoryContext,
  											   "COPY TO",
  											   ALLOCSET_DEFAULT_SIZES);
  
  	if (cstate->binary)
  	{
  		/* Generate header for a binary copy */
  		int32		tmp;
  
  		/* Signature */
  		CopySendData(cstate, BinarySignature, 11);
  		/* Flags field */
  		tmp = 0;
  		if (cstate->oids)
  			tmp |= (1 << 16);
  		CopySendInt32(cstate, tmp);
  		/* No header extension */
  		tmp = 0;
  		CopySendInt32(cstate, tmp);
  	}
  	else
  	{
  		/*
  		 * For non-binary copy, we need to convert null_print to file
  		 * encoding, because it will be sent directly with CopySendString.
  		 */
  		if (cstate->need_transcoding)
  			cstate->null_print_client = pg_server_to_any(cstate->null_print,
  														 cstate->null_print_len,
  														 cstate->file_encoding);
  
  		/* if a header has been requested send the line */
  		if (cstate->header_line)
  		{
  			bool		hdr_delim = false;
  
  			foreach(cur, cstate->attnumlist)
  			{
  				int			attnum = lfirst_int(cur);
  				char	   *colname;
  
  				if (hdr_delim)
  					CopySendChar(cstate, cstate->delim[0]);
  				hdr_delim = true;
  
  				colname = NameStr(TupleDescAttr(tupDesc, attnum - 1)->attname);
  
  				CopyAttributeOutCSV(cstate, colname, false,
  									list_length(cstate->attnumlist) == 1);
  			}
  
  			CopySendEndOfRow(cstate);
  		}
  	}
  
  	if (cstate->rel)
  	{
  		Datum	   *values;
  		bool	   *nulls;
  		HeapScanDesc scandesc;
  		HeapTuple	tuple;
  
  		values = (Datum *) palloc(num_phys_attrs * sizeof(Datum));
  		nulls = (bool *) palloc(num_phys_attrs * sizeof(bool));
  
  		scandesc = heap_beginscan(cstate->rel, GetActiveSnapshot(), 0, NULL);
  
  		processed = 0;
  		while ((tuple = heap_getnext(scandesc, ForwardScanDirection)) != NULL)
  		{
  			CHECK_FOR_INTERRUPTS();
  
  			/* Deconstruct the tuple ... faster than repeated heap_getattr */
  			heap_deform_tuple(tuple, tupDesc, values, nulls);
  
  			/* Format and send the data */
  			CopyOneRowTo(cstate, HeapTupleGetOid(tuple), values, nulls);
  			processed++;
  		}
  
  		heap_endscan(scandesc);
  
  		pfree(values);
  		pfree(nulls);
  	}
  	else
  	{
  		/* run the plan --- the dest receiver will send tuples */
  		ExecutorRun(cstate->queryDesc, ForwardScanDirection, 0L, true);
  		processed = ((DR_copy *) cstate->queryDesc->dest)->processed;
  	}
  
  	if (cstate->binary)
  	{
  		/* Generate trailer for a binary copy */
  		CopySendInt16(cstate, -1);
  		/* Need to flush out the trailer */
  		CopySendEndOfRow(cstate);
  	}
  
  	MemoryContextDelete(cstate->rowcontext);
  
  	return processed;
  }
  
  /*
   * Emit one row during CopyTo().
   */
  static void
  CopyOneRowTo(CopyState cstate, Oid tupleOid, Datum *values, bool *nulls)
  {
  	bool		need_delim = false;
  	FmgrInfo   *out_functions = cstate->out_functions;
  	MemoryContext oldcontext;
  	ListCell   *cur;
  	char	   *string;
  
  	MemoryContextReset(cstate->rowcontext);
  	oldcontext = MemoryContextSwitchTo(cstate->rowcontext);
  
  	if (cstate->binary)
  	{
  		/* Binary per-tuple header */
  		CopySendInt16(cstate, list_length(cstate->attnumlist));
  		/* Send OID if wanted --- note attnumlist doesn't include it */
  		if (cstate->oids)
  		{
  			/* Hack --- assume Oid is same size as int32 */
  			CopySendInt32(cstate, sizeof(int32));
  			CopySendInt32(cstate, tupleOid);
  		}
  	}
  	else
  	{
  		/* Text format has no per-tuple header, but send OID if wanted */
  		/* Assume digits don't need any quoting or encoding conversion */
  		if (cstate->oids)
  		{
  			string = DatumGetCString(DirectFunctionCall1(oidout,
  														 ObjectIdGetDatum(tupleOid)));
  			CopySendString(cstate, string);
  			need_delim = true;
  		}
  	}
  
  	foreach(cur, cstate->attnumlist)
  	{
  		int			attnum = lfirst_int(cur);
  		Datum		value = values[attnum - 1];
  		bool		isnull = nulls[attnum - 1];
  
  		if (!cstate->binary)
  		{
  			if (need_delim)
  				CopySendChar(cstate, cstate->delim[0]);
  			need_delim = true;
  		}
  
  		if (isnull)
  		{
  			if (!cstate->binary)
  				CopySendString(cstate, cstate->null_print_client);
  			else
  				CopySendInt32(cstate, -1);
  		}
  		else
  		{
  			if (!cstate->binary)
  			{
  				string = OutputFunctionCall(&out_functions[attnum - 1],
  											value);
  				if (cstate->csv_mode)
  					CopyAttributeOutCSV(cstate, string,
  										cstate->force_quote_flags[attnum - 1],
  										list_length(cstate->attnumlist) == 1);
  				else
  					CopyAttributeOutText(cstate, string);
  			}
  			else
  			{
  				bytea	   *outputbytes;
  
  				outputbytes = SendFunctionCall(&out_functions[attnum - 1],
  											   value);
  				CopySendInt32(cstate, VARSIZE(outputbytes) - VARHDRSZ);
  				CopySendData(cstate, VARDATA(outputbytes),
  							 VARSIZE(outputbytes) - VARHDRSZ);
  			}
  		}
  	}
  
  	CopySendEndOfRow(cstate);
  
  	MemoryContextSwitchTo(oldcontext);
  }
  
  
  /*
   * error context callback for COPY FROM
   *
   * The argument for the error context must be CopyState.
   */
  void
  CopyFromErrorCallback(void *arg)
  {
  	CopyState	cstate = (CopyState) arg;
  	char		curlineno_str[32];
  
  	snprintf(curlineno_str, sizeof(curlineno_str), UINT64_FORMAT,
  			 cstate->cur_lineno);
  
  	if (cstate->binary)
  	{
  		/* can't usefully display the data */
  		if (cstate->cur_attname)
  			errcontext("COPY %s, line %s, column %s",
  					   cstate->cur_relname, curlineno_str,
  					   cstate->cur_attname);
  		else
  			errcontext("COPY %s, line %s",
  					   cstate->cur_relname, curlineno_str);
  	}
  	else
  	{
  		if (cstate->cur_attname && cstate->cur_attval)
  		{
  			/* error is relevant to a particular column */
  			char	   *attval;
  
  			attval = limit_printout_length(cstate->cur_attval);
  			errcontext("COPY %s, line %s, column %s: \"%s\"",
  					   cstate->cur_relname, curlineno_str,
  					   cstate->cur_attname, attval);
  			pfree(attval);
  		}
  		else if (cstate->cur_attname)
  		{
  			/* error is relevant to a particular column, value is NULL */
  			errcontext("COPY %s, line %s, column %s: null input",
  					   cstate->cur_relname, curlineno_str,
  					   cstate->cur_attname);
  		}
  		else
  		{
  			/*
  			 * Error is relevant to a particular line.
  			 *
  			 * If line_buf still contains the correct line, and it's already
  			 * transcoded, print it. If it's still in a foreign encoding, it's
  			 * quite likely that the error is precisely a failure to do
  			 * encoding conversion (ie, bad data). We dare not try to convert
  			 * it, and at present there's no way to regurgitate it without
  			 * conversion. So we have to punt and just report the line number.
  			 */
  			if (cstate->line_buf_valid &&
  				(cstate->line_buf_converted || !cstate->need_transcoding))
  			{
  				char	   *lineval;
  
  				lineval = limit_printout_length(cstate->line_buf.data);
  				errcontext("COPY %s, line %s: \"%s\"",
  						   cstate->cur_relname, curlineno_str, lineval);
  				pfree(lineval);
  			}
  			else
  			{
  				errcontext("COPY %s, line %s",
  						   cstate->cur_relname, curlineno_str);
  			}
  		}
  	}
  }
  
  /*
   * Make sure we don't print an unreasonable amount of COPY data in a message.
   *
   * It would seem a lot easier to just use the sprintf "precision" limit to
   * truncate the string.  However, some versions of glibc have a bug/misfeature
   * that vsnprintf will always fail (return -1) if it is asked to truncate
   * a string that contains invalid byte sequences for the current encoding.
   * So, do our own truncation.  We return a pstrdup'd copy of the input.
   */
  static char *
  limit_printout_length(const char *str)
  {
  #define MAX_COPY_DATA_DISPLAY 100
  
  	int			slen = strlen(str);
  	int			len;
  	char	   *res;
  
  	/* Fast path if definitely okay */
  	if (slen <= MAX_COPY_DATA_DISPLAY)
  		return pstrdup(str);
  
  	/* Apply encoding-dependent truncation */
  	len = pg_mbcliplen(str, slen, MAX_COPY_DATA_DISPLAY);
  
  	/*
  	 * Truncate, and add "..." to show we truncated the input.
  	 */
  	res = (char *) palloc(len + 4);
  	memcpy(res, str, len);
  	strcpy(res + len, "...");
  
  	return res;
  }
  
  /*
   * Copy FROM file to relation.
   */
  uint64
  CopyFrom(CopyState cstate)
  {
  	HeapTuple	tuple;
  	TupleDesc	tupDesc;
  	Datum	   *values;
  	bool	   *nulls;
  	ResultRelInfo *resultRelInfo;
  	ResultRelInfo *saved_resultRelInfo = NULL;
  	EState	   *estate = CreateExecutorState(); /* for ExecConstraints() */
  	ModifyTableState *mtstate;
  	ExprContext *econtext;
  	TupleTableSlot *myslot;
  	MemoryContext oldcontext = CurrentMemoryContext;
  
  	ErrorContextCallback errcallback;
  	CommandId	mycid = GetCurrentCommandId(true);
  	int			hi_options = 0; /* start with default heap_insert options */
  	BulkInsertState bistate;
  	uint64		processed = 0;
  	bool		useMultiInsert;
  	bool		useYBMultiInsert;
  	bool		useHeapMultiInsert;
  	int			nBufferedTuples = 0;
  	int			prev_leaf_part_index = -1;
  
  #define MAX_BUFFERED_TUPLES 1000
  	HeapTuple  *bufferedTuples = NULL;	/* initialize to silence warning */
  	Size		bufferedTuplesSize = 0;
  	uint64		firstBufferedLineNo = 0;
  
  	Assert(cstate->rel);
  
  	/*
  	 * The target must be a plain, foreign, or partitioned relation, or have
  	 * an INSTEAD OF INSERT row trigger.  (Currently, such triggers are only
  	 * allowed on views, so we only hint about them in the view case.)
  	 */
  	if (cstate->rel->rd_rel->relkind != RELKIND_RELATION &&
  		cstate->rel->rd_rel->relkind != RELKIND_FOREIGN_TABLE &&
  		cstate->rel->rd_rel->relkind != RELKIND_PARTITIONED_TABLE &&
  		!(cstate->rel->trigdesc &&
  		  cstate->rel->trigdesc->trig_insert_instead_row))
  	{
  		if (cstate->rel->rd_rel->relkind == RELKIND_VIEW)
  			ereport(ERROR,
  					(errcode(ERRCODE_WRONG_OBJECT_TYPE),
  					 errmsg("cannot copy to view \"%s\"",
  							RelationGetRelationName(cstate->rel)),
  					 errhint("To enable copying to a view, provide an INSTEAD OF INSERT trigger.")));
  		else if (cstate->rel->rd_rel->relkind == RELKIND_MATVIEW)
  			ereport(ERROR,
  					(errcode(ERRCODE_WRONG_OBJECT_TYPE),
  					 errmsg("cannot copy to materialized view \"%s\"",
  							RelationGetRelationName(cstate->rel))));
  		else if (cstate->rel->rd_rel->relkind == RELKIND_SEQUENCE)
  			ereport(ERROR,
  					(errcode(ERRCODE_WRONG_OBJECT_TYPE),
  					 errmsg("cannot copy to sequence \"%s\"",
  							RelationGetRelationName(cstate->rel))));
  		else
  			ereport(ERROR,
  					(errcode(ERRCODE_WRONG_OBJECT_TYPE),
  					 errmsg("cannot copy to non-table relation \"%s\"",
  							RelationGetRelationName(cstate->rel))));
  	}
  
  	tupDesc = RelationGetDescr(cstate->rel);
  
  	/*----------
  	 * Check to see if we can avoid writing WAL
  	 *
  	 * If archive logging/streaming is not enabled *and* either
  	 *	- table was created in same transaction as this COPY
  	 *	- data is being written to relfilenode created in this transaction
  	 * then we can skip writing WAL.  It's safe because if the transaction
  	 * doesn't commit, we'll discard the table (or the new relfilenode file).
  	 * If it does commit, we'll have done the heap_sync at the bottom of this
  	 * routine first.
  	 *
  	 * As mentioned in comments in utils/rel.h, the in-same-transaction test
  	 * is not always set correctly, since in rare cases rd_newRelfilenodeSubid
  	 * can be cleared before the end of the transaction. The exact case is
  	 * when a relation sets a new relfilenode twice in same transaction, yet
  	 * the second one fails in an aborted subtransaction, e.g.
  	 *
  	 * BEGIN;
  	 * TRUNCATE t;
  	 * SAVEPOINT save;
  	 * TRUNCATE t;
  	 * ROLLBACK TO save;
  	 * COPY ...
  	 *
  	 * Also, if the target file is new-in-transaction, we assume that checking
  	 * FSM for free space is a waste of time, even if we must use WAL because
  	 * of archiving.  This could possibly be wrong, but it's unlikely.
  	 *
  	 * The comments for heap_insert and RelationGetBufferForTuple specify that
  	 * skipping WAL logging is only safe if we ensure that our tuples do not
  	 * go into pages containing tuples from any other transactions --- but this
  	 * must be the case if we have a new table or new relfilenode, so we need
  	 * no additional work to enforce that.
  	 *
  	 * We currently don't support this optimization if the COPY target is a
  	 * partitioned table as we currently only lazily initialize partition
  	 * information when routing the first tuple to the partition.  We cannot
  	 * know at this stage if we can perform this optimization.  It should be
  	 * possible to improve on this, but it does mean maintaining heap insert
  	 * option flags per partition and setting them when we first open the
  	 * partition.
  	 *
  	 * This optimization is not supported for relation types which do not
  	 * have any physical storage, with foreign tables and views using
  	 * INSTEAD OF triggers entering in this category.  Partitioned tables
  	 * are not supported as per the description above.
  	 *----------
  	 */
  	/* createSubid is creation check, newRelfilenodeSubid is truncation check */
  	if (cstate->rel->rd_rel->relkind != RELKIND_FOREIGN_TABLE &&
  		cstate->rel->rd_rel->relkind != RELKIND_PARTITIONED_TABLE &&
  		cstate->rel->rd_rel->relkind != RELKIND_VIEW &&
  		(cstate->rel->rd_createSubid != InvalidSubTransactionId ||
  		 cstate->rel->rd_newRelfilenodeSubid != InvalidSubTransactionId))
  	{
  		hi_options |= HEAP_INSERT_SKIP_FSM;
  		if (!XLogIsNeeded())
  			hi_options |= HEAP_INSERT_SKIP_WAL;
  	}
  
  	/*
  	 * Optimize if new relfilenode was created in this subxact or one of its
  	 * committed children and we won't see those rows later as part of an
  	 * earlier scan or command. The subxact test ensures that if this subxact
  	 * aborts then the frozen rows won't be visible after xact cleanup.  Note
  	 * that the stronger test of exactly which subtransaction created it is
  	 * crucial for correctness of this optimization. The test for an earlier
  	 * scan or command tolerates false negatives. FREEZE causes other sessions
  	 * to see rows they would not see under MVCC, and a false negative merely
  	 * spreads that anomaly to the current session.
  	 */
  	if (cstate->freeze)
  	{
  		/*
  		 * We currently disallow COPY FREEZE on partitioned tables.  The
  		 * reason for this is that we've simply not yet opened the partitions
  		 * to determine if the optimization can be applied to them.  We could
  		 * go and open them all here, but doing so may be quite a costly
  		 * overhead for small copies.  In any case, we may just end up routing
  		 * tuples to a small number of partitions.  It seems better just to
  		 * raise an ERROR for partitioned tables.
  		 */
  		if (cstate->rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
  		{
  			ereport(ERROR,
  				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
  					errmsg("cannot perform FREEZE on a partitioned table")));
  		}
  
  		/*
  		 * Tolerate one registration for the benefit of FirstXactSnapshot.
  		 * Scan-bearing queries generally create at least two registrations,
  		 * though relying on that is fragile, as is ignoring ActiveSnapshot.
  		 * Clear CatalogSnapshot to avoid counting its registration.  We'll
  		 * still detect ongoing catalog scans, each of which separately
  		 * registers the snapshot it uses.
  		 */
  		InvalidateCatalogSnapshot();
  		if (!ThereAreNoPriorRegisteredSnapshots() || !ThereAreNoReadyPortals())
  			ereport(ERROR,
  					(errcode(ERRCODE_INVALID_TRANSACTION_STATE),
  					 errmsg("cannot perform FREEZE because of prior transaction activity")));
  
  		if (cstate->rel->rd_createSubid != GetCurrentSubTransactionId() &&
  			cstate->rel->rd_newRelfilenodeSubid != GetCurrentSubTransactionId())
  			ereport(ERROR,
  					(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
  					 errmsg("cannot perform FREEZE because the table was not created or truncated in the current subtransaction")));
  
  		hi_options |= HEAP_INSERT_FROZEN;
  	}
  
  	/*
  	 * We need a ResultRelInfo so we can use the regular executor's
  	 * index-entry-making machinery.  (There used to be a huge amount of code
  	 * here that basically duplicated execUtils.c ...)
  	 */
  	resultRelInfo = makeNode(ResultRelInfo);
  	InitResultRelInfo(resultRelInfo,
  					  cstate->rel,
  					  1,		/* dummy rangetable index */
  					  NULL,
  					  0);
  
  	/* Verify the named relation is a valid target for INSERT */
  	CheckValidResultRel(resultRelInfo, CMD_INSERT);
  
  	ExecOpenIndices(resultRelInfo, false);
  
  	estate->es_result_relations = resultRelInfo;
  	estate->es_num_result_relations = 1;
  	estate->es_result_relation_info = resultRelInfo;
  	estate->es_range_table = cstate->range_table;
  
  	/* Set up a tuple slot too */
  	myslot = ExecInitExtraTupleSlot(estate, tupDesc);
  	/* Triggers might need a slot as well */
  	estate->es_trig_tuple_slot = ExecInitExtraTupleSlot(estate, NULL);
  
  	/*
  	 * Set up a ModifyTableState so we can let FDW(s) init themselves for
  	 * foreign-table result relation(s).
  	 */
  	mtstate = makeNode(ModifyTableState);
  	mtstate->ps.plan = NULL;
  	mtstate->ps.state = estate;
  	mtstate->operation = CMD_INSERT;
  	mtstate->resultRelInfo = estate->es_result_relations;
  
  	if (resultRelInfo->ri_FdwRoutine != NULL &&
  		resultRelInfo->ri_FdwRoutine->BeginForeignInsert != NULL)
  		resultRelInfo->ri_FdwRoutine->BeginForeignInsert(mtstate,
  														 resultRelInfo);
  
  	/* Prepare to catch AFTER triggers. */
  	AfterTriggerBeginQuery();
  
  	/*
  	 * If there are any triggers with transition tables on the named relation,
  	 * we need to be prepared to capture transition tuples.
  	 */
  	cstate->transition_capture =
  		MakeTransitionCaptureState(cstate->rel->trigdesc,
  								   RelationGetRelid(cstate->rel),
  								   CMD_INSERT);
  
  	/*
  	 * If the named relation is a partitioned table, initialize state for
  	 * CopyFrom tuple routing.
  	 */
  	if (cstate->rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
  	{
  		PartitionTupleRouting *proute;
  
  		proute = cstate->partition_tuple_routing =
  			ExecSetupPartitionTupleRouting(NULL, cstate->rel);
  
  		/*
  		 * If we are capturing transition tuples, they may need to be
  		 * converted from partition format back to partitioned table format
  		 * (this is only ever necessary if a BEFORE trigger modifies the
  		 * tuple).
  		 */
  		if (cstate->transition_capture != NULL)
  			ExecSetupChildParentMapForLeaf(proute);
  	}
  
  	/*
  	 * It's more efficient to prepare a bunch of tuples for insertion, and
  	 * insert them in one heap_multi_insert() call, than call heap_insert()
  	 * separately for every tuple. However, we can't do that if there are
  	 * BEFORE/INSTEAD OF triggers, or we need to evaluate volatile default
  	 * expressions. Such triggers or expressions might query the table we're
  	 * inserting to, and act differently if the tuples that have already been
  	 * processed and prepared for insertion are not there.  We also can't do
  	 * it if the table is foreign or partitioned.
  	 */
  	if ((resultRelInfo->ri_TrigDesc != NULL &&
  		 (resultRelInfo->ri_TrigDesc->trig_insert_before_row ||
  		  resultRelInfo->ri_TrigDesc->trig_insert_instead_row)) ||
  		resultRelInfo->ri_FdwRoutine != NULL ||
  		cstate->partition_tuple_routing != NULL ||
  		cstate->volatile_defexprs)
  	{
  		useMultiInsert = false;
  	}
  	else
  	{
  		useMultiInsert = true;
  	}
  
  	useYBMultiInsert = useMultiInsert && IsYBRelation(resultRelInfo->ri_RelationDesc);
  	useHeapMultiInsert = useMultiInsert && !IsYBRelation(resultRelInfo->ri_RelationDesc);
  	if (useHeapMultiInsert)
  	{
  		bufferedTuples = palloc(MAX_BUFFERED_TUPLES * sizeof(HeapTuple));
  	}
  
  	/*
  	 * Check BEFORE STATEMENT insertion triggers. It's debatable whether we
  	 * should do this for COPY, since it's not really an "INSERT" statement as
  	 * such. However, executing these triggers maintains consistency with the
  	 * EACH ROW triggers that we already fire on COPY.
  	 */
  	ExecBSInsertTriggers(estate, resultRelInfo);
  
  	values = (Datum *) palloc(tupDesc->natts * sizeof(Datum));
  	nulls = (bool *) palloc(tupDesc->natts * sizeof(bool));
  
  	bistate = GetBulkInsertState();
  	econtext = GetPerTupleExprContext(estate);
  
  	/* Set up callback to identify error line number */
  	errcallback.callback = CopyFromErrorCallback;
  	errcallback.arg = (void *) cstate;
  	errcallback.previous = error_context_stack;
  	error_context_stack = &errcallback;
  
  	if (useYBMultiInsert)
  		YBCStartBufferingWriteOperations();
  
  	PG_TRY();
  	{
  		for (;;)
  		{
  			TupleTableSlot *slot;
  			bool		skip_tuple;
  			Oid			loaded_oid = InvalidOid;
  
  			CHECK_FOR_INTERRUPTS();
  
  			if (nBufferedTuples == 0)
  			{
  				/*
  				 * Reset the per-tuple exprcontext. We can only do this if the
  				 * tuple buffer is empty. (Calling the context the per-tuple
  				 * memory context is a bit of a misnomer now.)
  				 */
  				ResetPerTupleExprContext(estate);
  			}
  
  			/* Switch into its memory context */
  			MemoryContextSwitchTo(GetPerTupleMemoryContext(estate));
  
  			if (!NextCopyFrom(cstate, econtext, values, nulls, &loaded_oid))
  				break;
  
  			/* And now we can form the input tuple. */
  			tuple = heap_form_tuple(tupDesc, values, nulls);
  
  			if (loaded_oid != InvalidOid)
  				HeapTupleSetOid(tuple, loaded_oid);
  
  			/*
  			 * Constraints might reference the tableoid column, so initialize
  			 * t_tableOid before evaluating them.
  			 */
  			tuple->t_tableOid = RelationGetRelid(resultRelInfo->ri_RelationDesc);
  
  			/* Triggers and stuff need to be invoked in query context. */
  			MemoryContextSwitchTo(oldcontext);
  
  			/* Place tuple in tuple slot --- but slot shouldn't free it */
  			slot = myslot;
  			ExecStoreTuple(tuple, slot, InvalidBuffer, false);
  
  			/* Determine the partition to heap_insert the tuple into */
  			if (cstate->partition_tuple_routing)
  			{
  				int			leaf_part_index;
  				PartitionTupleRouting *proute = cstate->partition_tuple_routing;
  
  				/*
  				 * Away we go ... If we end up not finding a partition after all,
  				 * ExecFindPartition() does not return and errors out instead.
  				 * Otherwise, the returned value is to be used as an index into
  				 * arrays mt_partitions[] and mt_partition_tupconv_maps[] that
  				 * will get us the ResultRelInfo and TupleConversionMap for the
  				 * partition, respectively.
  				 */
  				leaf_part_index = ExecFindPartition(resultRelInfo,
  													proute->partition_dispatch_info,
  													slot,
  													estate);
  				Assert(leaf_part_index >= 0 &&
  					   leaf_part_index < proute->num_partitions);
  
  				/*
  				 * If this tuple is mapped to a partition that is not same as the
  				 * previous one, we'd better make the bulk insert mechanism gets a
  				 * new buffer.
  				 */
  				if (prev_leaf_part_index != leaf_part_index)
  				{
  					ReleaseBulkInsertStatePin(bistate);
  					prev_leaf_part_index = leaf_part_index;
  				}
  
  				/*
  				 * Save the old ResultRelInfo and switch to the one corresponding
  				 * to the selected partition.
  				 */
  				saved_resultRelInfo = resultRelInfo;
  				resultRelInfo = proute->partitions[leaf_part_index];
  				if (resultRelInfo == NULL)
  				{
  					resultRelInfo = ExecInitPartitionInfo(mtstate,
  														  saved_resultRelInfo,
  														  proute, estate,
  														  leaf_part_index);
  					Assert(resultRelInfo != NULL);
  				}
  
  				/*
  				 * For ExecInsertIndexTuples() to work on the partition's indexes
  				 */
  				estate->es_result_relation_info = resultRelInfo;
  
  				/*
  				 * If we're capturing transition tuples, we might need to convert
  				 * from the partition rowtype to parent rowtype.
  				 */
  				if (cstate->transition_capture != NULL)
  				{
  					if (resultRelInfo->ri_TrigDesc &&
  						resultRelInfo->ri_TrigDesc->trig_insert_before_row)
  					{
  						/*
  						 * If there are any BEFORE triggers on the partition,
  						 * we'll have to be ready to convert their result back to
  						 * tuplestore format.
  						 */
  						cstate->transition_capture->tcs_original_insert_tuple = NULL;
  						cstate->transition_capture->tcs_map =
  							TupConvMapForLeaf(proute, saved_resultRelInfo,
  											  leaf_part_index);
  					}
  					else
  					{
  						/*
  						 * Otherwise, just remember the original unconverted
  						 * tuple, to avoid a needless round trip conversion.
  						 */
  						cstate->transition_capture->tcs_original_insert_tuple = tuple;
  						cstate->transition_capture->tcs_map = NULL;
  					}
  				}
  
  				/*
  				 * We might need to convert from the parent rowtype to the
  				 * partition rowtype.
  				 */
  				tuple = ConvertPartitionTupleSlot(proute->parent_child_tupconv_maps[leaf_part_index],
  												  tuple,
  												  proute->partition_tuple_slot,
  												  &slot);
  
  				tuple->t_tableOid = RelationGetRelid(resultRelInfo->ri_RelationDesc);
  			}
  
  			skip_tuple = false;
  
  			/* BEFORE ROW INSERT Triggers */
  			if (resultRelInfo->ri_TrigDesc &&
  				resultRelInfo->ri_TrigDesc->trig_insert_before_row)
  			{
  				slot = ExecBRInsertTriggers(estate, resultRelInfo, slot);
  
  				if (slot == NULL)	/* "do nothing" */
  					skip_tuple = true;
  				else				/* trigger might have changed tuple */
  					tuple = ExecMaterializeSlot(slot);
  			}
  
  			if (!skip_tuple)
  			{
  				if (resultRelInfo->ri_TrigDesc &&
  					resultRelInfo->ri_TrigDesc->trig_insert_instead_row)
  				{
  					/* Pass the data to the INSTEAD ROW INSERT trigger */
  					ExecIRInsertTriggers(estate, resultRelInfo, slot);
  				}
  				else
  				{
  					/*
  					 * If the target is a plain table, check the constraints of
  					 * the tuple.
  					 */
  					if (resultRelInfo->ri_FdwRoutine == NULL &&
  						resultRelInfo->ri_RelationDesc->rd_att->constr)
  						ExecConstraints(resultRelInfo, slot, estate);
  
  					/*
  					 * Also check the tuple against the partition constraint, if
  					 * there is one; except that if we got here via tuple-routing,
  					 * we don't need to if there's no BR trigger defined on the
  					 * partition.
  					 */
  					if (resultRelInfo->ri_PartitionCheck &&
  						(saved_resultRelInfo == NULL ||
  						 (resultRelInfo->ri_TrigDesc &&
  						  resultRelInfo->ri_TrigDesc->trig_insert_before_row)))
  						ExecPartitionCheck(resultRelInfo, slot, estate, true);
  
  					if (useHeapMultiInsert)
  					{
  						/* Add this tuple to the tuple buffer */
  						if (nBufferedTuples == 0)
  							firstBufferedLineNo = cstate->cur_lineno;
  						bufferedTuples[nBufferedTuples++] = tuple;
  						bufferedTuplesSize += tuple->t_len;
  
  						/*
  						 * If the buffer filled up, flush it.  Also flush if the
  						 * total size of all the tuples in the buffer becomes
  						 * large, to avoid using large amounts of memory for the
  						 * buffer when the tuples are exceptionally wide.
  						 */
  						if (nBufferedTuples == MAX_BUFFERED_TUPLES ||
  							bufferedTuplesSize > 65535)
  						{
  							CopyFromInsertBatch(cstate, estate, mycid, hi_options,
  												resultRelInfo, myslot, bistate,
  												nBufferedTuples, bufferedTuples,
  												firstBufferedLineNo);
  							nBufferedTuples = 0;
  							bufferedTuplesSize = 0;
  						}
  					}
  					else
  					{
  						List	   *recheckIndexes = NIL;
  
  						/* OK, store the tuple and create index entries for it */
  						if (IsYBRelation(resultRelInfo->ri_RelationDesc))
  						{
  							YBCExecuteInsert(cstate->rel, tupDesc, tuple);
  						}
  						else if (resultRelInfo->ri_FdwRoutine != NULL)
  						{
  							slot = resultRelInfo->ri_FdwRoutine->ExecForeignInsert(estate,
  																				   resultRelInfo,
  																				   slot,
  																				   NULL);
  
  							if (slot == NULL)	/* "do nothing" */
  								goto next_tuple;
  
  							/* FDW might have changed tuple */
  							tuple = ExecMaterializeSlot(slot);
  
  							/*
  							 * AFTER ROW Triggers might reference the tableoid
  							 * column, so initialize t_tableOid before evaluating
  							 * them.
  							 */
  							tuple->t_tableOid = RelationGetRelid(resultRelInfo->ri_RelationDesc);
  						}
  						else
  							heap_insert(resultRelInfo->ri_RelationDesc, tuple,
  										mycid, hi_options, bistate);
  
  						/* And create index entries for it */
  						if (resultRelInfo->ri_NumIndices > 0)
  							recheckIndexes = ExecInsertIndexTuples(slot,
  																   tuple,
  																   estate,
  																   false,
  																   NULL,
  																   NIL);
  
  						/* AFTER ROW INSERT Triggers */
  						ExecARInsertTriggers(estate, resultRelInfo, tuple,
  											 recheckIndexes, cstate->transition_capture);
  
  						list_free(recheckIndexes);
  					}
  				}
  
  				/*
  				 * We count only tuples not suppressed by a BEFORE INSERT trigger
  				 * or FDW; this is the same definition used by nodeModifyTable.c
  				 * for counting tuples inserted by an INSERT command.
  				 */
  				processed++;
  			}
  
  		next_tuple:
  			/* Restore the saved ResultRelInfo */
  			if (saved_resultRelInfo)
  			{
  				resultRelInfo = saved_resultRelInfo;
  				estate->es_result_relation_info = resultRelInfo;
  			}
  		}
  	}
  	PG_CATCH();
  	{
  		/* Flush any pending writes and reset the buffer count */
  		if (useYBMultiInsert)
  			YBCFlushBufferedWriteOperations();
  		PG_RE_THROW();
  	}
  	PG_END_TRY();
  
  	if (useYBMultiInsert)
  		YBCFlushBufferedWriteOperations();
  
  	/* Flush any remaining buffered tuples */
  	if (nBufferedTuples > 0)
  		CopyFromInsertBatch(cstate, estate, mycid, hi_options,
  							resultRelInfo, myslot, bistate,
  							nBufferedTuples, bufferedTuples,
  							firstBufferedLineNo);
  
  	/* Done, clean up */
  	error_context_stack = errcallback.previous;
  
  	FreeBulkInsertState(bistate);
  
  	MemoryContextSwitchTo(oldcontext);
  
  	/*
  	 * In the old protocol, tell pqcomm that we can process normal protocol
  	 * messages again.
  	 */
  	if (cstate->copy_dest == COPY_OLD_FE)
  		pq_endmsgread();
  
  	/* Execute AFTER STATEMENT insertion triggers */
  	ExecASInsertTriggers(estate, resultRelInfo, cstate->transition_capture);
  
  	/* Handle queued AFTER triggers */
  	AfterTriggerEndQuery(estate);
  
  	pfree(values);
  	pfree(nulls);
  
  	ExecResetTupleTable(estate->es_tupleTable, false);
  
  	/* Allow the FDW to shut down */
  	if (resultRelInfo->ri_FdwRoutine != NULL &&
  		resultRelInfo->ri_FdwRoutine->EndForeignInsert != NULL)
  		resultRelInfo->ri_FdwRoutine->EndForeignInsert(estate,
  													   resultRelInfo);
  
  	ExecCloseIndices(resultRelInfo);
  
  	/* Close all the partitioned tables, leaf partitions, and their indices */
  	if (cstate->partition_tuple_routing)
  		ExecCleanupTupleRouting(mtstate, cstate->partition_tuple_routing);
  
  	/* Close any trigger target relations */
  	ExecCleanUpTriggerState(estate);
  
  	FreeExecutorState(estate);
  
  	/*
  	 * If we skipped writing WAL, then we need to sync the heap (but not
  	 * indexes since those use WAL anyway)
  	 */
  	if (hi_options & HEAP_INSERT_SKIP_WAL)
  		heap_sync(cstate->rel);
  
  	return processed;
  }
  
  /*
   * A subroutine of CopyFrom, to write the current batch of buffered heap
   * tuples to the heap. Also updates indexes and runs AFTER ROW INSERT
   * triggers.
   */
  static void
  CopyFromInsertBatch(CopyState cstate, EState *estate, CommandId mycid,
  					int hi_options, ResultRelInfo *resultRelInfo,
  					TupleTableSlot *myslot, BulkInsertState bistate,
  					int nBufferedTuples, HeapTuple *bufferedTuples,
  					uint64 firstBufferedLineNo)
  {
  	MemoryContext oldcontext;
  	int			i;
  	uint64		save_cur_lineno;
  
  	/*
  	 * Print error context information correctly, if one of the operations
  	 * below fail.
  	 */
  	cstate->line_buf_valid = false;
  	save_cur_lineno = cstate->cur_lineno;
  
  	/*
  	 * heap_multi_insert leaks memory, so switch to short-lived memory context
  	 * before calling it.
  	 */
  	oldcontext = MemoryContextSwitchTo(GetPerTupleMemoryContext(estate));
  	heap_multi_insert(cstate->rel,
  					  bufferedTuples,
  					  nBufferedTuples,
  					  mycid,
  					  hi_options,
  					  bistate);
  	MemoryContextSwitchTo(oldcontext);
  
  	/*
  	 * If there are any indexes, update them for all the inserted tuples, and
  	 * run AFTER ROW INSERT triggers.
  	 */
  	if (resultRelInfo->ri_NumIndices > 0)
  	{
  		for (i = 0; i < nBufferedTuples; i++)
  		{
  			List	   *recheckIndexes;
  
  			cstate->cur_lineno = firstBufferedLineNo + i;
  			ExecStoreTuple(bufferedTuples[i], myslot, InvalidBuffer, false);
  			recheckIndexes =
  				ExecInsertIndexTuples(myslot, bufferedTuples[i],
  									  estate, false, NULL, NIL);
  			ExecARInsertTriggers(estate, resultRelInfo,
  								 bufferedTuples[i],
  								 recheckIndexes, cstate->transition_capture);
  			list_free(recheckIndexes);
  		}
  	}
  
  	/*
  	 * There's no indexes, but see if we need to run AFTER ROW INSERT triggers
  	 * anyway.
  	 */
  	else if (resultRelInfo->ri_TrigDesc != NULL &&
  			 (resultRelInfo->ri_TrigDesc->trig_insert_after_row ||
  			  resultRelInfo->ri_TrigDesc->trig_insert_new_table))
  	{
  		for (i = 0; i < nBufferedTuples; i++)
  		{
  			cstate->cur_lineno = firstBufferedLineNo + i;
  			ExecARInsertTriggers(estate, resultRelInfo,
  								 bufferedTuples[i],
  								 NIL, cstate->transition_capture);
  		}
  	}
  
  	/* reset cur_lineno to where we were */
  	cstate->cur_lineno = save_cur_lineno;
  }
  
  /*
   * Setup to read tuples from a file for COPY FROM.
   *
   * 'rel': Used as a template for the tuples
   * 'filename': Name of server-local file to read
   * 'attnamelist': List of char *, columns to include. NIL selects all cols.
   * 'options': List of DefElem. See copy_opt_item in gram.y for selections.
   *
   * Returns a CopyState, to be passed to NextCopyFrom and related functions.
   */
  CopyState
  BeginCopyFrom(ParseState *pstate,
  			  Relation rel,
  			  const char *filename,
  			  bool is_program,
  			  copy_data_source_cb data_source_cb,
  			  List *attnamelist,
  			  List *options)
  {
  	CopyState	cstate;
  	bool		pipe = (filename == NULL);
  	TupleDesc	tupDesc;
  	AttrNumber	num_phys_attrs,
  				num_defaults;
  	FmgrInfo   *in_functions;
  	Oid		   *typioparams;
  	int			attnum;
  	Oid			in_func_oid;
  	int		   *defmap;
  	ExprState **defexprs;
  	MemoryContext oldcontext;
  	bool		volatile_defexprs;
  
  	cstate = BeginCopy(pstate, true, rel, NULL, InvalidOid, attnamelist, options);
  	oldcontext = MemoryContextSwitchTo(cstate->copycontext);
  
  	/* Initialize state variables */
  	cstate->reached_eof = false;
  	cstate->eol_type = EOL_UNKNOWN;
  	cstate->cur_relname = RelationGetRelationName(cstate->rel);
  	cstate->cur_lineno = 0;
  	cstate->cur_attname = NULL;
  	cstate->cur_attval = NULL;
  
  	/* Set up variables to avoid per-attribute overhead. */
  	initStringInfo(&cstate->attribute_buf);
  	initStringInfo(&cstate->line_buf);
  	cstate->line_buf_converted = false;
  	cstate->raw_buf = (char *) palloc(RAW_BUF_SIZE + 1);
  	cstate->raw_buf_index = cstate->raw_buf_len = 0;
  
  	/* Assign range table, we'll need it in CopyFrom. */
  	if (pstate)
  		cstate->range_table = pstate->p_rtable;
  
  	tupDesc = RelationGetDescr(cstate->rel);
  	num_phys_attrs = tupDesc->natts;
  	num_defaults = 0;
  	volatile_defexprs = false;
  
  	/*
  	 * Pick up the required catalog information for each attribute in the
  	 * relation, including the input function, the element type (to pass to
  	 * the input function), and info about defaults and constraints. (Which
  	 * input function we use depends on text/binary format choice.)
  	 */
  	in_functions = (FmgrInfo *) palloc(num_phys_attrs * sizeof(FmgrInfo));
  	typioparams = (Oid *) palloc(num_phys_attrs * sizeof(Oid));
  	defmap = (int *) palloc(num_phys_attrs * sizeof(int));
  	defexprs = (ExprState **) palloc(num_phys_attrs * sizeof(ExprState *));
  
  	for (attnum = 1; attnum <= num_phys_attrs; attnum++)
  	{
  		Form_pg_attribute att = TupleDescAttr(tupDesc, attnum - 1);
  
  		/* We don't need info for dropped attributes */
  		if (att->attisdropped)
  			continue;
  
  		/* Fetch the input function and typioparam info */
  		if (cstate->binary)
  			getTypeBinaryInputInfo(att->atttypid,
  								   &in_func_oid, &typioparams[attnum - 1]);
  		else
  			getTypeInputInfo(att->atttypid,
  							 &in_func_oid, &typioparams[attnum - 1]);
  		fmgr_info(in_func_oid, &in_functions[attnum - 1]);
  
  		/* Get default info if needed */
  		if (!list_member_int(cstate->attnumlist, attnum))
  		{
  			/* attribute is NOT to be copied from input */
  			/* use default value if one exists */
  			Expr	   *defexpr = (Expr *) build_column_default(cstate->rel,
  																attnum);
  
  			if (defexpr != NULL)
  			{
  				/* Run the expression through planner */
  				defexpr = expression_planner(defexpr);
  
  				/* Initialize executable expression in copycontext */
  				defexprs[num_defaults] = ExecInitExpr(defexpr, NULL);
  				defmap[num_defaults] = attnum - 1;
  				num_defaults++;
  
  				/*
  				 * If a default expression looks at the table being loaded,
  				 * then it could give the wrong answer when using
  				 * multi-insert. Since database access can be dynamic this is
  				 * hard to test for exactly, so we use the much wider test of
  				 * whether the default expression is volatile. We allow for
  				 * the special case of when the default expression is the
  				 * nextval() of a sequence which in this specific case is
  				 * known to be safe for use with the multi-insert
  				 * optimization. Hence we use this special case function
  				 * checker rather than the standard check for
  				 * contain_volatile_functions().
  				 */
  				if (!volatile_defexprs)
  					volatile_defexprs = contain_volatile_functions_not_nextval((Node *) defexpr);
  			}
  		}
  	}
  
  	/* We keep those variables in cstate. */
  	cstate->in_functions = in_functions;
  	cstate->typioparams = typioparams;
  	cstate->defmap = defmap;
  	cstate->defexprs = defexprs;
  	cstate->volatile_defexprs = volatile_defexprs;
  	cstate->num_defaults = num_defaults;
  	cstate->is_program = is_program;
  
  	if (data_source_cb)
  	{
  		cstate->copy_dest = COPY_CALLBACK;
  		cstate->data_source_cb = data_source_cb;
  	}
  	else if (pipe)
  	{
  		Assert(!is_program);	/* the grammar does not allow this */
  		if (whereToSendOutput == DestRemote)
  			ReceiveCopyBegin(cstate);
  		else
  			cstate->copy_file = stdin;
  	}
  	else
  	{
  		cstate->filename = pstrdup(filename);
  
  		if (cstate->is_program)
  		{
  			cstate->copy_file = OpenPipeStream(cstate->filename, PG_BINARY_R);
  			if (cstate->copy_file == NULL)
  				ereport(ERROR,
  						(errcode_for_file_access(),
  						 errmsg("could not execute command \"%s\": %m",
  								cstate->filename)));
  		}
  		else
  		{
  			struct stat st;
  
  			cstate->copy_file = AllocateFile(cstate->filename, PG_BINARY_R);
  			if (cstate->copy_file == NULL)
  			{
  				/* copy errno because ereport subfunctions might change it */
  				int			save_errno = errno;
  
  				ereport(ERROR,
  						(errcode_for_file_access(),
  						 errmsg("could not open file \"%s\" for reading: %m",
  								cstate->filename),
  						 (save_errno == ENOENT || save_errno == EACCES) ?
  						 errhint("COPY FROM instructs the PostgreSQL server process to read a file. "
  								 "You may want a client-side facility such as psql's \\copy.") : 0));
  			}
  
  			if (fstat(fileno(cstate->copy_file), &st))
  				ereport(ERROR,
  						(errcode_for_file_access(),
  						 errmsg("could not stat file \"%s\": %m",
  								cstate->filename)));
  
  			if (S_ISDIR(st.st_mode))
  				ereport(ERROR,
  						(errcode(ERRCODE_WRONG_OBJECT_TYPE),
  						 errmsg("\"%s\" is a directory", cstate->filename)));
  		}
  	}
  
  	if (!cstate->binary)
  	{
  		/* must rely on user to tell us... */
  		cstate->file_has_oids = cstate->oids;
  	}
  	else
  	{
  		/* Read and verify binary header */
  		char		readSig[11];
  		int32		tmp;
  
  		/* Signature */
  		if (CopyGetData(cstate, readSig, 11, 11) != 11 ||
  			memcmp(readSig, BinarySignature, 11) != 0)
  			ereport(ERROR,
  					(errcode(ERRCODE_BAD_COPY_FILE_FORMAT),
  					 errmsg("COPY file signature not recognized")));
  		/* Flags field */
  		if (!CopyGetInt32(cstate, &tmp))
  			ereport(ERROR,
  					(errcode(ERRCODE_BAD_COPY_FILE_FORMAT),
  					 errmsg("invalid COPY file header (missing flags)")));
  		cstate->file_has_oids = (tmp & (1 << 16)) != 0;
  		tmp &= ~(1 << 16);
  		if ((tmp >> 16) != 0)
  			ereport(ERROR,
  					(errcode(ERRCODE_BAD_COPY_FILE_FORMAT),
  					 errmsg("unrecognized critical flags in COPY file header")));
  		/* Header extension length */
  		if (!CopyGetInt32(cstate, &tmp) ||
  			tmp < 0)
  			ereport(ERROR,
  					(errcode(ERRCODE_BAD_COPY_FILE_FORMAT),
  					 errmsg("invalid COPY file header (missing length)")));
  		/* Skip extension header, if present */
  		while (tmp-- > 0)
  		{
  			if (CopyGetData(cstate, readSig, 1, 1) != 1)
  				ereport(ERROR,
  						(errcode(ERRCODE_BAD_COPY_FILE_FORMAT),
  						 errmsg("invalid COPY file header (wrong length)")));
  		}
  	}
  
  	if (cstate->file_has_oids && cstate->binary)
  	{
  		getTypeBinaryInputInfo(OIDOID,
  							   &in_func_oid, &cstate->oid_typioparam);
  		fmgr_info(in_func_oid, &cstate->oid_in_function);
  	}
  
  	/* create workspace for CopyReadAttributes results */
  	if (!cstate->binary)
  	{
  		AttrNumber	attr_count = list_length(cstate->attnumlist);
  		int			nfields = cstate->file_has_oids ? (attr_count + 1) : attr_count;
  
  		cstate->max_fields = nfields;
  		cstate->raw_fields = (char **) palloc(nfields * sizeof(char *));
  	}
  
  	MemoryContextSwitchTo(oldcontext);
  
  	return cstate;
  }
  
  /*
   * Read raw fields in the next line for COPY FROM in text or csv mode.
   * Return false if no more lines.
   *
   * An internal temporary buffer is returned via 'fields'. It is valid until
   * the next call of the function. Since the function returns all raw fields
   * in the input file, 'nfields' could be different from the number of columns
   * in the relation.
   *
   * NOTE: force_not_null option are not applied to the returned fields.
   */
  bool
  NextCopyFromRawFields(CopyState cstate, char ***fields, int *nfields)
  {
  	int			fldct;
  	bool		done;
  
  	/* only available for text or csv input */
  	Assert(!cstate->binary);
  
  	/* on input just throw the header line away */
  	if (cstate->cur_lineno == 0 && cstate->header_line)
  	{
  		cstate->cur_lineno++;
  		if (CopyReadLine(cstate))
  			return false;		/* done */
  	}
  
  	cstate->cur_lineno++;
  
  	/* Actually read the line into memory here */
  	done = CopyReadLine(cstate);
  
  	/*
  	 * EOF at start of line means we're done.  If we see EOF after some
  	 * characters, we act as though it was newline followed by EOF, ie,
  	 * process the line and then exit loop on next iteration.
  	 */
  	if (done && cstate->line_buf.len == 0)
  		return false;
  
  	/* Parse the line into de-escaped field values */
  	if (cstate->csv_mode)
  		fldct = CopyReadAttributesCSV(cstate);
  	else
  		fldct = CopyReadAttributesText(cstate);
  
  	*fields = cstate->raw_fields;
  	*nfields = fldct;
  	return true;
  }
  
  /*
   * Read next tuple from file for COPY FROM. Return false if no more tuples.
   *
   * 'econtext' is used to evaluate default expression for each columns not
   * read from the file. It can be NULL when no default values are used, i.e.
   * when all columns are read from the file.
   *
   * 'values' and 'nulls' arrays must be the same length as columns of the
   * relation passed to BeginCopyFrom. This function fills the arrays.
   * Oid of the tuple is returned with 'tupleOid' separately.
   */
  bool
  NextCopyFrom(CopyState cstate, ExprContext *econtext,
  			 Datum *values, bool *nulls, Oid *tupleOid)
  {
  	TupleDesc	tupDesc;
  	AttrNumber	num_phys_attrs,
  				attr_count,
  				num_defaults = cstate->num_defaults;
  	FmgrInfo   *in_functions = cstate->in_functions;
  	Oid		   *typioparams = cstate->typioparams;
  	int			i;
  	int			nfields;
  	bool		isnull;
  	bool		file_has_oids = cstate->file_has_oids;
  	int		   *defmap = cstate->defmap;
  	ExprState **defexprs = cstate->defexprs;
  
  	tupDesc = RelationGetDescr(cstate->rel);
  	num_phys_attrs = tupDesc->natts;
  	attr_count = list_length(cstate->attnumlist);
  	nfields = file_has_oids ? (attr_count + 1) : attr_count;
  
  	/* Initialize all values for row to NULL */
  	MemSet(values, 0, num_phys_attrs * sizeof(Datum));
  	MemSet(nulls, true, num_phys_attrs * sizeof(bool));
  
  	if (!cstate->binary)
  	{
  		char	  **field_strings;
  		ListCell   *cur;
  		int			fldct;
  		int			fieldno;
  		char	   *string;
  
  		/* read raw fields in the next line */
  		if (!NextCopyFromRawFields(cstate, &field_strings, &fldct))
  			return false;
  
  		/* check for overflowing fields */
  		if (nfields > 0 && fldct > nfields)
  			ereport(ERROR,
  					(errcode(ERRCODE_BAD_COPY_FILE_FORMAT),
  					 errmsg("extra data after last expected column")));
  
  		fieldno = 0;
  
  		/* Read the OID field if present */
  		if (file_has_oids)
  		{
  			if (fieldno >= fldct)
  				ereport(ERROR,
  						(errcode(ERRCODE_BAD_COPY_FILE_FORMAT),
  						 errmsg("missing data for OID column")));
  			string = field_strings[fieldno++];
  
  			if (string == NULL)
  				ereport(ERROR,
  						(errcode(ERRCODE_BAD_COPY_FILE_FORMAT),
  						 errmsg("null OID in COPY data")));
  			else if (cstate->oids && tupleOid != NULL)
  			{
  				cstate->cur_attname = "oid";
  				cstate->cur_attval = string;
  				*tupleOid = DatumGetObjectId(DirectFunctionCall1(oidin,
  																 CStringGetDatum(string)));
  				if (*tupleOid == InvalidOid)
  					ereport(ERROR,
  							(errcode(ERRCODE_BAD_COPY_FILE_FORMAT),
  							 errmsg("invalid OID in COPY data")));
  				cstate->cur_attname = NULL;
  				cstate->cur_attval = NULL;
  			}
  		}
  
  		/* Loop to read the user attributes on the line. */
  		foreach(cur, cstate->attnumlist)
  		{
  			int			attnum = lfirst_int(cur);
  			int			m = attnum - 1;
  			Form_pg_attribute att = TupleDescAttr(tupDesc, m);
  
  			if (fieldno >= fldct)
  				ereport(ERROR,
  						(errcode(ERRCODE_BAD_COPY_FILE_FORMAT),
  						 errmsg("missing data for column \"%s\"",
  								NameStr(att->attname))));
  			string = field_strings[fieldno++];
  
  			if (cstate->convert_select_flags &&
  				!cstate->convert_select_flags[m])
  			{
  				/* ignore input field, leaving column as NULL */
  				continue;
  			}
  
  			if (cstate->csv_mode)
  			{
  				if (string == NULL &&
  					cstate->force_notnull_flags[m])
  				{
  					/*
  					 * FORCE_NOT_NULL option is set and column is NULL -
  					 * convert it to the NULL string.
  					 */
  					string = cstate->null_print;
  				}
  				else if (string != NULL && cstate->force_null_flags[m]
  						 && strcmp(string, cstate->null_print) == 0)
  				{
  					/*
  					 * FORCE_NULL option is set and column matches the NULL
  					 * string. It must have been quoted, or otherwise the
  					 * string would already have been set to NULL. Convert it
  					 * to NULL as specified.
  					 */
  					string = NULL;
  				}
  			}
  
  			cstate->cur_attname = NameStr(att->attname);
  			cstate->cur_attval = string;
  			values[m] = InputFunctionCall(&in_functions[m],
  										  string,
  										  typioparams[m],
  										  att->atttypmod);
  			if (string != NULL)
  				nulls[m] = false;
  			cstate->cur_attname = NULL;
  			cstate->cur_attval = NULL;
  		}
  
  		Assert(fieldno == nfields);
  	}
  	else
  	{
  		/* binary */
  		int16		fld_count;
  		ListCell   *cur;
  
  		cstate->cur_lineno++;
  
  		if (!CopyGetInt16(cstate, &fld_count))
  		{
  			/* EOF detected (end of file, or protocol-level EOF) */
  			return false;
  		}
  
  		if (fld_count == -1)
  		{
  			/*
  			 * Received EOF marker.  In a V3-protocol copy, wait for the
  			 * protocol-level EOF, and complain if it doesn't come
  			 * immediately.  This ensures that we correctly handle CopyFail,
  			 * if client chooses to send that now.
  			 *
  			 * Note that we MUST NOT try to read more data in an old-protocol
  			 * copy, since there is no protocol-level EOF marker then.  We
  			 * could go either way for copy from file, but choose to throw
  			 * error if there's data after the EOF marker, for consistency
  			 * with the new-protocol case.
  			 */
  			char		dummy;
  
  			if (cstate->copy_dest != COPY_OLD_FE &&
  				CopyGetData(cstate, &dummy, 1, 1) > 0)
  				ereport(ERROR,
  						(errcode(ERRCODE_BAD_COPY_FILE_FORMAT),
  						 errmsg("received copy data after EOF marker")));
  			return false;
  		}
  
  		if (fld_count != attr_count)
  			ereport(ERROR,
  					(errcode(ERRCODE_BAD_COPY_FILE_FORMAT),
  					 errmsg("row field count is %d, expected %d",
  							(int) fld_count, attr_count)));
  
  		if (file_has_oids)
  		{
  			Oid			loaded_oid;
  
  			cstate->cur_attname = "oid";
  			loaded_oid =
  				DatumGetObjectId(CopyReadBinaryAttribute(cstate,
  														 0,
  														 &cstate->oid_in_function,
  														 cstate->oid_typioparam,
  														 -1,
  														 &isnull));
  			if (isnull || loaded_oid == InvalidOid)
  				ereport(ERROR,
  						(errcode(ERRCODE_BAD_COPY_FILE_FORMAT),
  						 errmsg("invalid OID in COPY data")));
  			cstate->cur_attname = NULL;
  			if (cstate->oids && tupleOid != NULL)
  				*tupleOid = loaded_oid;
  		}
  
  		i = 0;
  		foreach(cur, cstate->attnumlist)
  		{
  			int			attnum = lfirst_int(cur);
  			int			m = attnum - 1;
  			Form_pg_attribute att = TupleDescAttr(tupDesc, m);
  
  			cstate->cur_attname = NameStr(att->attname);
  			i++;
  			values[m] = CopyReadBinaryAttribute(cstate,
  												i,
  												&in_functions[m],
  												typioparams[m],
  												att->atttypmod,
  												&nulls[m]);
  			cstate->cur_attname = NULL;
  		}
  	}
  
  	/*
  	 * Now compute and insert any defaults available for the columns not
  	 * provided by the input data.  Anything not processed here or above will
  	 * remain NULL.
  	 */
  	for (i = 0; i < num_defaults; i++)
  	{
  		/*
  		 * The caller must supply econtext and have switched into the
  		 * per-tuple memory context in it.
  		 */
  		Assert(econtext != NULL);
  		Assert(CurrentMemoryContext == econtext->ecxt_per_tuple_memory);
  
  		values[defmap[i]] = ExecEvalExpr(defexprs[i], econtext,
  										 &nulls[defmap[i]]);
  	}
  
  	return true;
  }
  
  /*
   * Clean up storage and release resources for COPY FROM.
   */
  void
  EndCopyFrom(CopyState cstate)
  {
  	/* No COPY FROM related resources except memory. */
  
  	EndCopy(cstate);
  }
  
  /*
   * Read the next input line and stash it in line_buf, with conversion to
   * server encoding.
   *
   * Result is true if read was terminated by EOF, false if terminated
   * by newline.  The terminating newline or EOF marker is not included
   * in the final value of line_buf.
   */
  static bool
  CopyReadLine(CopyState cstate)
  {
  	bool		result;
  
  	resetStringInfo(&cstate->line_buf);
  	cstate->line_buf_valid = true;
  
  	/* Mark that encoding conversion hasn't occurred yet */
  	cstate->line_buf_converted = false;
  
  	/* Parse data and transfer into line_buf */
  	result = CopyReadLineText(cstate);
  
  	if (result)
  	{
  		/*
  		 * Reached EOF.  In protocol version 3, we should ignore anything
  		 * after \. up to the protocol end of copy data.  (XXX maybe better
  		 * not to treat \. as special?)
  		 */
  		if (cstate->copy_dest == COPY_NEW_FE)
  		{
  			do
  			{
  				cstate->raw_buf_index = cstate->raw_buf_len;
  			} while (CopyLoadRawBuf(cstate));
  		}
  	}
  	else
  	{
  		/*
  		 * If we didn't hit EOF, then we must have transferred the EOL marker
  		 * to line_buf along with the data.  Get rid of it.
  		 */
  		switch (cstate->eol_type)
  		{
  			case EOL_NL:
  				Assert(cstate->line_buf.len >= 1);
  				Assert(cstate->line_buf.data[cstate->line_buf.len - 1] == '\n');
  				cstate->line_buf.len--;
  				cstate->line_buf.data[cstate->line_buf.len] = '\0';
  				break;
  			case EOL_CR:
  				Assert(cstate->line_buf.len >= 1);
  				Assert(cstate->line_buf.data[cstate->line_buf.len - 1] == '\r');
  				cstate->line_buf.len--;
  				cstate->line_buf.data[cstate->line_buf.len] = '\0';
  				break;
  			case EOL_CRNL:
  				Assert(cstate->line_buf.len >= 2);
  				Assert(cstate->line_buf.data[cstate->line_buf.len - 2] == '\r');
  				Assert(cstate->line_buf.data[cstate->line_buf.len - 1] == '\n');
  				cstate->line_buf.len -= 2;
  				cstate->line_buf.data[cstate->line_buf.len] = '\0';
  				break;
  			case EOL_UNKNOWN:
  				/* shouldn't get here */
  				Assert(false);
  				break;
  		}
  	}
  
  	/* Done reading the line.  Convert it to server encoding. */
  	if (cstate->need_transcoding)
  	{
  		char	   *cvt;
  
  		cvt = pg_any_to_server(cstate->line_buf.data,
  							   cstate->line_buf.len,
  							   cstate->file_encoding);
  		if (cvt != cstate->line_buf.data)
  		{
  			/* transfer converted data back to line_buf */
  			resetStringInfo(&cstate->line_buf);
  			appendBinaryStringInfo(&cstate->line_buf, cvt, strlen(cvt));
  			pfree(cvt);
  		}
  	}
  
  	/* Now it's safe to use the buffer in error messages */
  	cstate->line_buf_converted = true;
  
  	return result;
  }
  
  /*
   * CopyReadLineText - inner loop of CopyReadLine for text mode
   */
  static bool
  CopyReadLineText(CopyState cstate)
  {
  	char	   *copy_raw_buf;
  	int			raw_buf_ptr;
  	int			copy_buf_len;
  	bool		need_data = false;
  	bool		hit_eof = false;
  	bool		result = false;
  	char		mblen_str[2];
  
  	/* CSV variables */
  	bool		first_char_in_line = true;
  	bool		in_quote = false,
  				last_was_esc = false;
  	char		quotec = '\0';
  	char		escapec = '\0';
  
  	if (cstate->csv_mode)
  	{
  		quotec = cstate->quote[0];
  		escapec = cstate->escape[0];
  		/* ignore special escape processing if it's the same as quotec */
  		if (quotec == escapec)
  			escapec = '\0';
  	}
  
  	mblen_str[1] = '\0';
  
  	/*
  	 * The objective of this loop is to transfer the entire next input line
  	 * into line_buf.  Hence, we only care for detecting newlines (\r and/or
  	 * \n) and the end-of-copy marker (\.).
  	 *
  	 * In CSV mode, \r and \n inside a quoted field are just part of the data
  	 * value and are put in line_buf.  We keep just enough state to know if we
  	 * are currently in a quoted field or not.
  	 *
  	 * These four characters, and the CSV escape and quote characters, are
  	 * assumed the same in frontend and backend encodings.
  	 *
  	 * For speed, we try to move data from raw_buf to line_buf in chunks
  	 * rather than one character at a time.  raw_buf_ptr points to the next
  	 * character to examine; any characters from raw_buf_index to raw_buf_ptr
  	 * have been determined to be part of the line, but not yet transferred to
  	 * line_buf.
  	 *
  	 * For a little extra speed within the loop, we copy raw_buf and
  	 * raw_buf_len into local variables.
  	 */
  	copy_raw_buf = cstate->raw_buf;
  	raw_buf_ptr = cstate->raw_buf_index;
  	copy_buf_len = cstate->raw_buf_len;
  
  	for (;;)
  	{
  		int			prev_raw_ptr;
  		char		c;
  
  		/*
  		 * Load more data if needed.  Ideally we would just force four bytes
  		 * of read-ahead and avoid the many calls to
  		 * IF_NEED_REFILL_AND_NOT_EOF_CONTINUE(), but the COPY_OLD_FE protocol
  		 * does not allow us to read too far ahead or we might read into the
  		 * next data, so we read-ahead only as far we know we can.  One
  		 * optimization would be to read-ahead four byte here if
  		 * cstate->copy_dest != COPY_OLD_FE, but it hardly seems worth it,
  		 * considering the size of the buffer.
  		 */
  		if (raw_buf_ptr >= copy_buf_len || need_data)
  		{
  			REFILL_LINEBUF;
  
  			/*
  			 * Try to read some more data.  This will certainly reset
  			 * raw_buf_index to zero, and raw_buf_ptr must go with it.
  			 */
  			if (!CopyLoadRawBuf(cstate))
  				hit_eof = true;
  			raw_buf_ptr = 0;
  			copy_buf_len = cstate->raw_buf_len;
  
  			/*
  			 * If we are completely out of data, break out of the loop,
  			 * reporting EOF.
  			 */
  			if (copy_buf_len <= 0)
  			{
  				result = true;
  				break;
  			}
  			need_data = false;
  		}
  
  		/* OK to fetch a character */
  		prev_raw_ptr = raw_buf_ptr;
  		c = copy_raw_buf[raw_buf_ptr++];
  
  		if (cstate->csv_mode)
  		{
  			/*
  			 * If character is '\\' or '\r', we may need to look ahead below.
  			 * Force fetch of the next character if we don't already have it.
  			 * We need to do this before changing CSV state, in case one of
  			 * these characters is also the quote or escape character.
  			 *
  			 * Note: old-protocol does not like forced prefetch, but it's OK
  			 * here since we cannot validly be at EOF.
  			 */
  			if (c == '\\' || c == '\r')
  			{
  				IF_NEED_REFILL_AND_NOT_EOF_CONTINUE(0);
  			}
  
  			/*
  			 * Dealing with quotes and escapes here is mildly tricky. If the
  			 * quote char is also the escape char, there's no problem - we
  			 * just use the char as a toggle. If they are different, we need
  			 * to ensure that we only take account of an escape inside a
  			 * quoted field and immediately preceding a quote char, and not
  			 * the second in an escape-escape sequence.
  			 */
  			if (in_quote && c == escapec)
  				last_was_esc = !last_was_esc;
  			if (c == quotec && !last_was_esc)
  				in_quote = !in_quote;
  			if (c != escapec)
  				last_was_esc = false;
  
  			/*
  			 * Updating the line count for embedded CR and/or LF chars is
  			 * necessarily a little fragile - this test is probably about the
  			 * best we can do.  (XXX it's arguable whether we should do this
  			 * at all --- is cur_lineno a physical or logical count?)
  			 */
  			if (in_quote && c == (cstate->eol_type == EOL_NL ? '\n' : '\r'))
  				cstate->cur_lineno++;
  		}
  
  		/* Process \r */
  		if (c == '\r' && (!cstate->csv_mode || !in_quote))
  		{
  			/* Check for \r\n on first line, _and_ handle \r\n. */
  			if (cstate->eol_type == EOL_UNKNOWN ||
  				cstate->eol_type == EOL_CRNL)
  			{
  				/*
  				 * If need more data, go back to loop top to load it.
  				 *
  				 * Note that if we are at EOF, c will wind up as '\0' because
  				 * of the guaranteed pad of raw_buf.
  				 */
  				IF_NEED_REFILL_AND_NOT_EOF_CONTINUE(0);
  
  				/* get next char */
  				c = copy_raw_buf[raw_buf_ptr];
  
  				if (c == '\n')
  				{
  					raw_buf_ptr++;	/* eat newline */
  					cstate->eol_type = EOL_CRNL;	/* in case not set yet */
  				}
  				else
  				{
  					/* found \r, but no \n */
  					if (cstate->eol_type == EOL_CRNL)
  						ereport(ERROR,
  								(errcode(ERRCODE_BAD_COPY_FILE_FORMAT),
  								 !cstate->csv_mode ?
  								 errmsg("literal carriage return found in data") :
  								 errmsg("unquoted carriage return found in data"),
  								 !cstate->csv_mode ?
  								 errhint("Use \"\\r\" to represent carriage return.") :
  								 errhint("Use quoted CSV field to represent carriage return.")));
  
  					/*
  					 * if we got here, it is the first line and we didn't find
  					 * \n, so don't consume the peeked character
  					 */
  					cstate->eol_type = EOL_CR;
  				}
  			}
  			else if (cstate->eol_type == EOL_NL)
  				ereport(ERROR,
  						(errcode(ERRCODE_BAD_COPY_FILE_FORMAT),
  						 !cstate->csv_mode ?
  						 errmsg("literal carriage return found in data") :
  						 errmsg("unquoted carriage return found in data"),
  						 !cstate->csv_mode ?
  						 errhint("Use \"\\r\" to represent carriage return.") :
  						 errhint("Use quoted CSV field to represent carriage return.")));
  			/* If reach here, we have found the line terminator */
  			break;
  		}
  
  		/* Process \n */
  		if (c == '\n' && (!cstate->csv_mode || !in_quote))
  		{
  			if (cstate->eol_type == EOL_CR || cstate->eol_type == EOL_CRNL)
  				ereport(ERROR,
  						(errcode(ERRCODE_BAD_COPY_FILE_FORMAT),
  						 !cstate->csv_mode ?
  						 errmsg("literal newline found in data") :
  						 errmsg("unquoted newline found in data"),
  						 !cstate->csv_mode ?
  						 errhint("Use \"\\n\" to represent newline.") :
  						 errhint("Use quoted CSV field to represent newline.")));
  			cstate->eol_type = EOL_NL;	/* in case not set yet */
  			/* If reach here, we have found the line terminator */
  			break;
  		}
  
  		/*
  		 * In CSV mode, we only recognize \. alone on a line.  This is because
  		 * \. is a valid CSV data value.
  		 */
  		if (c == '\\' && (!cstate->csv_mode || first_char_in_line))
  		{
  			char		c2;
  
  			IF_NEED_REFILL_AND_NOT_EOF_CONTINUE(0);
  			IF_NEED_REFILL_AND_EOF_BREAK(0);
  
  			/* -----
  			 * get next character
  			 * Note: we do not change c so if it isn't \., we can fall
  			 * through and continue processing for file encoding.
  			 * -----
  			 */
  			c2 = copy_raw_buf[raw_buf_ptr];
  
  			if (c2 == '.')
  			{
  				raw_buf_ptr++;	/* consume the '.' */
  
  				/*
  				 * Note: if we loop back for more data here, it does not
  				 * matter that the CSV state change checks are re-executed; we
  				 * will come back here with no important state changed.
  				 */
  				if (cstate->eol_type == EOL_CRNL)
  				{
  					/* Get the next character */
  					IF_NEED_REFILL_AND_NOT_EOF_CONTINUE(0);
  					/* if hit_eof, c2 will become '\0' */
  					c2 = copy_raw_buf[raw_buf_ptr++];
  
  					if (c2 == '\n')
  					{
  						if (!cstate->csv_mode)
  							ereport(ERROR,
  									(errcode(ERRCODE_BAD_COPY_FILE_FORMAT),
  									 errmsg("end-of-copy marker does not match previous newline style")));
  						else
  							NO_END_OF_COPY_GOTO;
  					}
  					else if (c2 != '\r')
  					{
  						if (!cstate->csv_mode)
  							ereport(ERROR,
  									(errcode(ERRCODE_BAD_COPY_FILE_FORMAT),
  									 errmsg("end-of-copy marker corrupt")));
  						else
  							NO_END_OF_COPY_GOTO;
  					}
  				}
  
  				/* Get the next character */
  				IF_NEED_REFILL_AND_NOT_EOF_CONTINUE(0);
  				/* if hit_eof, c2 will become '\0' */
  				c2 = copy_raw_buf[raw_buf_ptr++];
  
  				if (c2 != '\r' && c2 != '\n')
  				{
  					if (!cstate->csv_mode)
  						ereport(ERROR,
  								(errcode(ERRCODE_BAD_COPY_FILE_FORMAT),
  								 errmsg("end-of-copy marker corrupt")));
  					else
  						NO_END_OF_COPY_GOTO;
  				}
  
  				if ((cstate->eol_type == EOL_NL && c2 != '\n') ||
  					(cstate->eol_type == EOL_CRNL && c2 != '\n') ||
  					(cstate->eol_type == EOL_CR && c2 != '\r'))
  				{
  					ereport(ERROR,
  							(errcode(ERRCODE_BAD_COPY_FILE_FORMAT),
  							 errmsg("end-of-copy marker does not match previous newline style")));
  				}
  
  				/*
  				 * Transfer only the data before the \. into line_buf, then
  				 * discard the data and the \. sequence.
  				 */
  				if (prev_raw_ptr > cstate->raw_buf_index)
  					appendBinaryStringInfo(&cstate->line_buf,
  										   cstate->raw_buf + cstate->raw_buf_index,
  										   prev_raw_ptr - cstate->raw_buf_index);
  				cstate->raw_buf_index = raw_buf_ptr;
  				result = true;	/* report EOF */
  				break;
  			}
  			else if (!cstate->csv_mode)
  
  				/*
  				 * If we are here, it means we found a backslash followed by
  				 * something other than a period.  In non-CSV mode, anything
  				 * after a backslash is special, so we skip over that second
  				 * character too.  If we didn't do that \\. would be
  				 * considered an eof-of copy, while in non-CSV mode it is a
  				 * literal backslash followed by a period.  In CSV mode,
  				 * backslashes are not special, so we want to process the
  				 * character after the backslash just like a normal character,
  				 * so we don't increment in those cases.
  				 */
  				raw_buf_ptr++;
  		}
  
  		/*
  		 * This label is for CSV cases where \. appears at the start of a
  		 * line, but there is more text after it, meaning it was a data value.
  		 * We are more strict for \. in CSV mode because \. could be a data
  		 * value, while in non-CSV mode, \. cannot be a data value.
  		 */
  not_end_of_copy:
  
  		/*
  		 * Process all bytes of a multi-byte character as a group.
  		 *
  		 * We only support multi-byte sequences where the first byte has the
  		 * high-bit set, so as an optimization we can avoid this block
  		 * entirely if it is not set.
  		 */
  		if (cstate->encoding_embeds_ascii && IS_HIGHBIT_SET(c))
  		{
  			int			mblen;
  
  			mblen_str[0] = c;
  			/* All our encodings only read the first byte to get the length */
  			mblen = pg_encoding_mblen(cstate->file_encoding, mblen_str);
  			IF_NEED_REFILL_AND_NOT_EOF_CONTINUE(mblen - 1);
  			IF_NEED_REFILL_AND_EOF_BREAK(mblen - 1);
  			raw_buf_ptr += mblen - 1;
  		}
  		first_char_in_line = false;
  	}							/* end of outer loop */
  
  	/*
  	 * Transfer any still-uncopied data to line_buf.
  	 */
  	REFILL_LINEBUF;
  
  	return result;
  }
  
  /*
   *	Return decimal value for a hexadecimal digit
   */
  static int
  GetDecimalFromHex(char hex)
  {
  	if (isdigit((unsigned char) hex))
  		return hex - '0';
  	else
  		return tolower((unsigned char) hex) - 'a' + 10;
  }
  
  /*
   * Parse the current line into separate attributes (fields),
   * performing de-escaping as needed.
   *
   * The input is in line_buf.  We use attribute_buf to hold the result
   * strings.  cstate->raw_fields[k] is set to point to the k'th attribute
   * string, or NULL when the input matches the null marker string.
   * This array is expanded as necessary.
   *
   * (Note that the caller cannot check for nulls since the returned
   * string would be the post-de-escaping equivalent, which may look
   * the same as some valid data string.)
   *
   * delim is the column delimiter string (must be just one byte for now).
   * null_print is the null marker string.  Note that this is compared to
   * the pre-de-escaped input string.
   *
   * The return value is the number of fields actually read.
   */
  static int
  CopyReadAttributesText(CopyState cstate)
  {
  	char		delimc = cstate->delim[0];
  	int			fieldno;
  	char	   *output_ptr;
  	char	   *cur_ptr;
  	char	   *line_end_ptr;
  
  	/*
  	 * We need a special case for zero-column tables: check that the input
  	 * line is empty, and return.
  	 */
  	if (cstate->max_fields <= 0)
  	{
  		if (cstate->line_buf.len != 0)
  			ereport(ERROR,
  					(errcode(ERRCODE_BAD_COPY_FILE_FORMAT),
  					 errmsg("extra data after last expected column")));
  		return 0;
  	}
  
  	resetStringInfo(&cstate->attribute_buf);
  
  	/*
  	 * The de-escaped attributes will certainly not be longer than the input
  	 * data line, so we can just force attribute_buf to be large enough and
  	 * then transfer data without any checks for enough space.  We need to do
  	 * it this way because enlarging attribute_buf mid-stream would invalidate
  	 * pointers already stored into cstate->raw_fields[].
  	 */
  	if (cstate->attribute_buf.maxlen <= cstate->line_buf.len)
  		enlargeStringInfo(&cstate->attribute_buf, cstate->line_buf.len);
  	output_ptr = cstate->attribute_buf.data;
  
  	/* set pointer variables for loop */
  	cur_ptr = cstate->line_buf.data;
  	line_end_ptr = cstate->line_buf.data + cstate->line_buf.len;
  
  	/* Outer loop iterates over fields */
  	fieldno = 0;
  	for (;;)
  	{
  		bool		found_delim = false;
  		char	   *start_ptr;
  		char	   *end_ptr;
  		int			input_len;
  		bool		saw_non_ascii = false;
  
  		/* Make sure there is enough space for the next value */
  		if (fieldno >= cstate->max_fields)
  		{
  			cstate->max_fields *= 2;
  			cstate->raw_fields =
  				repalloc(cstate->raw_fields, cstate->max_fields * sizeof(char *));
  		}
  
  		/* Remember start of field on both input and output sides */
  		start_ptr = cur_ptr;
  		cstate->raw_fields[fieldno] = output_ptr;
  
  		/*
  		 * Scan data for field.
  		 *
  		 * Note that in this loop, we are scanning to locate the end of field
  		 * and also speculatively performing de-escaping.  Once we find the
  		 * end-of-field, we can match the raw field contents against the null
  		 * marker string.  Only after that comparison fails do we know that
  		 * de-escaping is actually the right thing to do; therefore we *must
  		 * not* throw any syntax errors before we've done the null-marker
  		 * check.
  		 */
  		for (;;)
  		{
  			char		c;
  
  			end_ptr = cur_ptr;
  			if (cur_ptr >= line_end_ptr)
  				break;
  			c = *cur_ptr++;
  			if (c == delimc)
  			{
  				found_delim = true;
  				break;
  			}
  			if (c == '\\')
  			{
  				if (cur_ptr >= line_end_ptr)
  					break;
  				c = *cur_ptr++;
  				switch (c)
  				{
  					case '0':
  					case '1':
  					case '2':
  					case '3':
  					case '4':
  					case '5':
  					case '6':
  					case '7':
  						{
  							/* handle \013 */
  							int			val;
  
  							val = OCTVALUE(c);
  							if (cur_ptr < line_end_ptr)
  							{
  								c = *cur_ptr;
  								if (ISOCTAL(c))
  								{
  									cur_ptr++;
  									val = (val << 3) + OCTVALUE(c);
  									if (cur_ptr < line_end_ptr)
  									{
  										c = *cur_ptr;
  										if (ISOCTAL(c))
  										{
  											cur_ptr++;
  											val = (val << 3) + OCTVALUE(c);
  										}
  									}
  								}
  							}
  							c = val & 0377;
  							if (c == '\0' || IS_HIGHBIT_SET(c))
  								saw_non_ascii = true;
  						}
  						break;
  					case 'x':
  						/* Handle \x3F */
  						if (cur_ptr < line_end_ptr)
  						{
  							char		hexchar = *cur_ptr;
  
  							if (isxdigit((unsigned char) hexchar))
  							{
  								int			val = GetDecimalFromHex(hexchar);
  
  								cur_ptr++;
  								if (cur_ptr < line_end_ptr)
  								{
  									hexchar = *cur_ptr;
  									if (isxdigit((unsigned char) hexchar))
  									{
  										cur_ptr++;
  										val = (val << 4) + GetDecimalFromHex(hexchar);
  									}
  								}
  								c = val & 0xff;
  								if (c == '\0' || IS_HIGHBIT_SET(c))
  									saw_non_ascii = true;
  							}
  						}
  						break;
  					case 'b':
  						c = '\b';
  						break;
  					case 'f':
  						c = '\f';
  						break;
  					case 'n':
  						c = '\n';
  						break;
  					case 'r':
  						c = '\r';
  						break;
  					case 't':
  						c = '\t';
  						break;
  					case 'v':
  						c = '\v';
  						break;
  
  						/*
  						 * in all other cases, take the char after '\'
  						 * literally
  						 */
  				}
  			}
  
  			/* Add c to output string */
  			*output_ptr++ = c;
  		}
  
  		/* Check whether raw input matched null marker */
  		input_len = end_ptr - start_ptr;
  		if (input_len == cstate->null_print_len &&
  			strncmp(start_ptr, cstate->null_print, input_len) == 0)
  			cstate->raw_fields[fieldno] = NULL;
  		else
  		{
  			/*
  			 * At this point we know the field is supposed to contain data.
  			 *
  			 * If we de-escaped any non-7-bit-ASCII chars, make sure the
  			 * resulting string is valid data for the db encoding.
  			 */
  			if (saw_non_ascii)
  			{
  				char	   *fld = cstate->raw_fields[fieldno];
  
  				pg_verifymbstr(fld, output_ptr - fld, false);
  			}
  		}
  
  		/* Terminate attribute value in output area */
  		*output_ptr++ = '\0';
  
  		fieldno++;
  		/* Done if we hit EOL instead of a delim */
  		if (!found_delim)
  			break;
  	}
  
  	/* Clean up state of attribute_buf */
  	output_ptr--;
  	Assert(*output_ptr == '\0');
  	cstate->attribute_buf.len = (output_ptr - cstate->attribute_buf.data);
  
  	return fieldno;
  }
  
  /*
   * Parse the current line into separate attributes (fields),
   * performing de-escaping as needed.  This has exactly the same API as
   * CopyReadAttributesText, except we parse the fields according to
   * "standard" (i.e. common) CSV usage.
   */
  static int
  CopyReadAttributesCSV(CopyState cstate)
  {
  	char		delimc = cstate->delim[0];
  	char		quotec = cstate->quote[0];
  	char		escapec = cstate->escape[0];
  	int			fieldno;
  	char	   *output_ptr;
  	char	   *cur_ptr;
  	char	   *line_end_ptr;
  
  	/*
  	 * We need a special case for zero-column tables: check that the input
  	 * line is empty, and return.
  	 */
  	if (cstate->max_fields <= 0)
  	{
  		if (cstate->line_buf.len != 0)
  			ereport(ERROR,
  					(errcode(ERRCODE_BAD_COPY_FILE_FORMAT),
  					 errmsg("extra data after last expected column")));
  		return 0;
  	}
  
  	resetStringInfo(&cstate->attribute_buf);
  
  	/*
  	 * The de-escaped attributes will certainly not be longer than the input
  	 * data line, so we can just force attribute_buf to be large enough and
  	 * then transfer data without any checks for enough space.  We need to do
  	 * it this way because enlarging attribute_buf mid-stream would invalidate
  	 * pointers already stored into cstate->raw_fields[].
  	 */
  	if (cstate->attribute_buf.maxlen <= cstate->line_buf.len)
  		enlargeStringInfo(&cstate->attribute_buf, cstate->line_buf.len);
  	output_ptr = cstate->attribute_buf.data;
  
  	/* set pointer variables for loop */
  	cur_ptr = cstate->line_buf.data;
  	line_end_ptr = cstate->line_buf.data + cstate->line_buf.len;
  
  	/* Outer loop iterates over fields */
  	fieldno = 0;
  	for (;;)
  	{
  		bool		found_delim = false;
  		bool		saw_quote = false;
  		char	   *start_ptr;
  		char	   *end_ptr;
  		int			input_len;
  
  		/* Make sure there is enough space for the next value */
  		if (fieldno >= cstate->max_fields)
  		{
  			cstate->max_fields *= 2;
  			cstate->raw_fields =
  				repalloc(cstate->raw_fields, cstate->max_fields * sizeof(char *));
  		}
  
  		/* Remember start of field on both input and output sides */
  		start_ptr = cur_ptr;
  		cstate->raw_fields[fieldno] = output_ptr;
  
  		/*
  		 * Scan data for field,
  		 *
  		 * The loop starts in "not quote" mode and then toggles between that
  		 * and "in quote" mode. The loop exits normally if it is in "not
  		 * quote" mode and a delimiter or line end is seen.
  		 */
  		for (;;)
  		{
  			char		c;
  
  			/* Not in quote */
  			for (;;)
  			{
  				end_ptr = cur_ptr;
  				if (cur_ptr >= line_end_ptr)
  					goto endfield;
  				c = *cur_ptr++;
  				/* unquoted field delimiter */
  				if (c == delimc)
  				{
  					found_delim = true;
  					goto endfield;
  				}
  				/* start of quoted field (or part of field) */
  				if (c == quotec)
  				{
  					saw_quote = true;
  					break;
  				}
  				/* Add c to output string */
  				*output_ptr++ = c;
  			}
  
  			/* In quote */
  			for (;;)
  			{
  				end_ptr = cur_ptr;
  				if (cur_ptr >= line_end_ptr)
  					ereport(ERROR,
  							(errcode(ERRCODE_BAD_COPY_FILE_FORMAT),
  							 errmsg("unterminated CSV quoted field")));
  
  				c = *cur_ptr++;
  
  				/* escape within a quoted field */
  				if (c == escapec)
  				{
  					/*
  					 * peek at the next char if available, and escape it if it
  					 * is an escape char or a quote char
  					 */
  					if (cur_ptr < line_end_ptr)
  					{
  						char		nextc = *cur_ptr;
  
  						if (nextc == escapec || nextc == quotec)
  						{
  							*output_ptr++ = nextc;
  							cur_ptr++;
  							continue;
  						}
  					}
  				}
  
  				/*
  				 * end of quoted field. Must do this test after testing for
  				 * escape in case quote char and escape char are the same
  				 * (which is the common case).
  				 */
  				if (c == quotec)
  					break;
  
  				/* Add c to output string */
  				*output_ptr++ = c;
  			}
  		}
  endfield:
  
  		/* Terminate attribute value in output area */
  		*output_ptr++ = '\0';
  
  		/* Check whether raw input matched null marker */
  		input_len = end_ptr - start_ptr;
  		if (!saw_quote && input_len == cstate->null_print_len &&
  			strncmp(start_ptr, cstate->null_print, input_len) == 0)
  			cstate->raw_fields[fieldno] = NULL;
  
  		fieldno++;
  		/* Done if we hit EOL instead of a delim */
  		if (!found_delim)
  			break;
  	}
  
  	/* Clean up state of attribute_buf */
  	output_ptr--;
  	Assert(*output_ptr == '\0');
  	cstate->attribute_buf.len = (output_ptr - cstate->attribute_buf.data);
  
  	return fieldno;
  }
  
  
  /*
   * Read a binary attribute
   */
  static Datum
  CopyReadBinaryAttribute(CopyState cstate,
  						int column_no, FmgrInfo *flinfo,
  						Oid typioparam, int32 typmod,
  						bool *isnull)
  {
  	int32		fld_size;
  	Datum		result;
  
  	if (!CopyGetInt32(cstate, &fld_size))
  		ereport(ERROR,
  				(errcode(ERRCODE_BAD_COPY_FILE_FORMAT),
  				 errmsg("unexpected EOF in COPY data")));
  	if (fld_size == -1)
  	{
  		*isnull = true;
  		return ReceiveFunctionCall(flinfo, NULL, typioparam, typmod);
  	}
  	if (fld_size < 0)
  		ereport(ERROR,
  				(errcode(ERRCODE_BAD_COPY_FILE_FORMAT),
  				 errmsg("invalid field size")));
  
  	/* reset attribute_buf to empty, and load raw data in it */
  	resetStringInfo(&cstate->attribute_buf);
  
  	enlargeStringInfo(&cstate->attribute_buf, fld_size);
  	if (CopyGetData(cstate, cstate->attribute_buf.data,
  					fld_size, fld_size) != fld_size)
  		ereport(ERROR,
  				(errcode(ERRCODE_BAD_COPY_FILE_FORMAT),
  				 errmsg("unexpected EOF in COPY data")));
  
  	cstate->attribute_buf.len = fld_size;
  	cstate->attribute_buf.data[fld_size] = '\0';
  
  	/* Call the column type's binary input converter */
  	result = ReceiveFunctionCall(flinfo, &cstate->attribute_buf,
  								 typioparam, typmod);
  
  	/* Trouble if it didn't eat the whole buffer */
  	if (cstate->attribute_buf.cursor != cstate->attribute_buf.len)
  		ereport(ERROR,
  				(errcode(ERRCODE_INVALID_BINARY_REPRESENTATION),
  				 errmsg("incorrect binary data format")));
  
  	*isnull = false;
  	return result;
  }
  
  /*
   * Send text representation of one attribute, with conversion and escaping
   */
  #define DUMPSOFAR() \
  	do { \
  		if (ptr > start) \
  			CopySendData(cstate, start, ptr - start); \
  	} while (0)
  
  static void
  CopyAttributeOutText(CopyState cstate, char *string)
  {
  	char	   *ptr;
  	char	   *start;
  	char		c;
  	char		delimc = cstate->delim[0];
  
  	if (cstate->need_transcoding)
  		ptr = pg_server_to_any(string, strlen(string), cstate->file_encoding);
  	else
  		ptr = string;
  
  	/*
  	 * We have to grovel through the string searching for control characters
  	 * and instances of the delimiter character.  In most cases, though, these
  	 * are infrequent.  To avoid overhead from calling CopySendData once per
  	 * character, we dump out all characters between escaped characters in a
  	 * single call.  The loop invariant is that the data from "start" to "ptr"
  	 * can be sent literally, but hasn't yet been.
  	 *
  	 * We can skip pg_encoding_mblen() overhead when encoding is safe, because
  	 * in valid backend encodings, extra bytes of a multibyte character never
  	 * look like ASCII.  This loop is sufficiently performance-critical that
  	 * it's worth making two copies of it to get the IS_HIGHBIT_SET() test out
  	 * of the normal safe-encoding path.
  	 */
  	if (cstate->encoding_embeds_ascii)
  	{
  		start = ptr;
  		while ((c = *ptr) != '\0')
  		{
  			if ((unsigned char) c < (unsigned char) 0x20)
  			{
  				/*
  				 * \r and \n must be escaped, the others are traditional. We
  				 * prefer to dump these using the C-like notation, rather than
  				 * a backslash and the literal character, because it makes the
  				 * dump file a bit more proof against Microsoftish data
  				 * mangling.
  				 */
  				switch (c)
  				{
  					case '\b':
  						c = 'b';
  						break;
  					case '\f':
  						c = 'f';
  						break;
  					case '\n':
  						c = 'n';
  						break;
  					case '\r':
  						c = 'r';
  						break;
  					case '\t':
  						c = 't';
  						break;
  					case '\v':
  						c = 'v';
  						break;
  					default:
  						/* If it's the delimiter, must backslash it */
  						if (c == delimc)
  							break;
  						/* All ASCII control chars are length 1 */
  						ptr++;
  						continue;	/* fall to end of loop */
  				}
  				/* if we get here, we need to convert the control char */
  				DUMPSOFAR();
  				CopySendChar(cstate, '\\');
  				CopySendChar(cstate, c);
  				start = ++ptr;	/* do not include char in next run */
  			}
  			else if (c == '\\' || c == delimc)
  			{
  				DUMPSOFAR();
  				CopySendChar(cstate, '\\');
  				start = ptr++;	/* we include char in next run */
  			}
  			else if (IS_HIGHBIT_SET(c))
  				ptr += pg_encoding_mblen(cstate->file_encoding, ptr);
  			else
  				ptr++;
  		}
  	}
  	else
  	{
  		start = ptr;
  		while ((c = *ptr) != '\0')
  		{
  			if ((unsigned char) c < (unsigned char) 0x20)
  			{
  				/*
  				 * \r and \n must be escaped, the others are traditional. We
  				 * prefer to dump these using the C-like notation, rather than
  				 * a backslash and the literal character, because it makes the
  				 * dump file a bit more proof against Microsoftish data
  				 * mangling.
  				 */
  				switch (c)
  				{
  					case '\b':
  						c = 'b';
  						break;
  					case '\f':
  						c = 'f';
  						break;
  					case '\n':
  						c = 'n';
  						break;
  					case '\r':
  						c = 'r';
  						break;
  					case '\t':
  						c = 't';
  						break;
  					case '\v':
  						c = 'v';
  						break;
  					default:
  						/* If it's the delimiter, must backslash it */
  						if (c == delimc)
  							break;
  						/* All ASCII control chars are length 1 */
  						ptr++;
  						continue;	/* fall to end of loop */
  				}
  				/* if we get here, we need to convert the control char */
  				DUMPSOFAR();
  				CopySendChar(cstate, '\\');
  				CopySendChar(cstate, c);
  				start = ++ptr;	/* do not include char in next run */
  			}
  			else if (c == '\\' || c == delimc)
  			{
  				DUMPSOFAR();
  				CopySendChar(cstate, '\\');
  				start = ptr++;	/* we include char in next run */
  			}
  			else
  				ptr++;
  		}
  	}
  
  	DUMPSOFAR();
  }
  
  /*
   * Send text representation of one attribute, with conversion and
   * CSV-style escaping
   */
  static void
  CopyAttributeOutCSV(CopyState cstate, char *string,
  					bool use_quote, bool single_attr)
  {
  	char	   *ptr;
  	char	   *start;
  	char		c;
  	char		delimc = cstate->delim[0];
  	char		quotec = cstate->quote[0];
  	char		escapec = cstate->escape[0];
  
  	/* force quoting if it matches null_print (before conversion!) */
  	if (!use_quote && strcmp(string, cstate->null_print) == 0)
  		use_quote = true;
  
  	if (cstate->need_transcoding)
  		ptr = pg_server_to_any(string, strlen(string), cstate->file_encoding);
  	else
  		ptr = string;
  
  	/*
  	 * Make a preliminary pass to discover if it needs quoting
  	 */
  	if (!use_quote)
  	{
  		/*
  		 * Because '\.' can be a data value, quote it if it appears alone on a
  		 * line so it is not interpreted as the end-of-data marker.
  		 */
  		if (single_attr && strcmp(ptr, "\\.") == 0)
  			use_quote = true;
  		else
  		{
  			char	   *tptr = ptr;
  
  			while ((c = *tptr) != '\0')
  			{
  				if (c == delimc || c == quotec || c == '\n' || c == '\r')
  				{
  					use_quote = true;
  					break;
  				}
  				if (IS_HIGHBIT_SET(c) && cstate->encoding_embeds_ascii)
  					tptr += pg_encoding_mblen(cstate->file_encoding, tptr);
  				else
  					tptr++;
  			}
  		}
  	}
  
  	if (use_quote)
  	{
  		CopySendChar(cstate, quotec);
  
  		/*
  		 * We adopt the same optimization strategy as in CopyAttributeOutText
  		 */
  		start = ptr;
  		while ((c = *ptr) != '\0')
  		{
  			if (c == quotec || c == escapec)
  			{
  				DUMPSOFAR();
  				CopySendChar(cstate, escapec);
  				start = ptr;	/* we include char in next run */
  			}
  			if (IS_HIGHBIT_SET(c) && cstate->encoding_embeds_ascii)
  				ptr += pg_encoding_mblen(cstate->file_encoding, ptr);
  			else
  				ptr++;
  		}
  		DUMPSOFAR();
  
  		CopySendChar(cstate, quotec);
  	}
  	else
  	{
  		/* If it doesn't need quoting, we can just dump it as-is */
  		CopySendString(cstate, ptr);
  	}
  }
  
  /*
   * CopyGetAttnums - build an integer list of attnums to be copied
   *
   * The input attnamelist is either the user-specified column list,
   * or NIL if there was none (in which case we want all the non-dropped
   * columns).
   *
   * rel can be NULL ... it's only used for error reports.
   */
  static List *
  CopyGetAttnums(TupleDesc tupDesc, Relation rel, List *attnamelist)
  {
  	List	   *attnums = NIL;
  
  	if (attnamelist == NIL)
  	{
  		/* Generate default column list */
  		int			attr_count = tupDesc->natts;
  		int			i;
  
  		for (i = 0; i < attr_count; i++)
  		{
  			if (TupleDescAttr(tupDesc, i)->attisdropped)
  				continue;
  			attnums = lappend_int(attnums, i + 1);
  		}
  	}
  	else
  	{
  		/* Validate the user-supplied list and extract attnums */
  		ListCell   *l;
  
  		foreach(l, attnamelist)
  		{
  			char	   *name = strVal(lfirst(l));
  			int			attnum;
  			int			i;
  
  			/* Lookup column name */
  			attnum = InvalidAttrNumber;
  			for (i = 0; i < tupDesc->natts; i++)
  			{
  				Form_pg_attribute att = TupleDescAttr(tupDesc, i);
  
  				if (att->attisdropped)
  					continue;
  				if (namestrcmp(&(att->attname), name) == 0)
  				{
  					attnum = att->attnum;
  					break;
  				}
  			}
  			if (attnum == InvalidAttrNumber)
  			{
  				if (rel != NULL)
  					ereport(ERROR,
  							(errcode(ERRCODE_UNDEFINED_COLUMN),
  							 errmsg("column \"%s\" of relation \"%s\" does not exist",
  									name, RelationGetRelationName(rel))));
  				else
  					ereport(ERROR,
  							(errcode(ERRCODE_UNDEFINED_COLUMN),
  							 errmsg("column \"%s\" does not exist",
  									name)));
  			}
  			/* Check for duplicates */
  			if (list_member_int(attnums, attnum))
  				ereport(ERROR,
  						(errcode(ERRCODE_DUPLICATE_COLUMN),
  						 errmsg("column \"%s\" specified more than once",
  								name)));
  			attnums = lappend_int(attnums, attnum);
  		}
  	}
  
  	return attnums;
  }
  
  
  /*
   * copy_dest_startup --- executor startup
   */
  static void
  copy_dest_startup(DestReceiver *self, int operation, TupleDesc typeinfo)
  {
  	/* no-op */
  }
  
  /*
   * copy_dest_receive --- receive one tuple
   */
  static bool
  copy_dest_receive(TupleTableSlot *slot, DestReceiver *self)
  {
  	DR_copy    *myState = (DR_copy *) self;
  	CopyState	cstate = myState->cstate;
  
  	/* Make sure the tuple is fully deconstructed */
  	slot_getallattrs(slot);
  
  	/* And send the data */
  	CopyOneRowTo(cstate, InvalidOid, slot->tts_values, slot->tts_isnull);
  	myState->processed++;
  
  	return true;
  }
  
  /*
   * copy_dest_shutdown --- executor end
   */
  static void
  copy_dest_shutdown(DestReceiver *self)
  {
  	/* no-op */
  }
  
  /*
   * copy_dest_destroy --- release DestReceiver object
   */
  static void
  copy_dest_destroy(DestReceiver *self)
  {
  	pfree(self);
  }
  
  /*
   * CreateCopyDestReceiver -- create a suitable DestReceiver object
   */
  DestReceiver *
  CreateCopyDestReceiver(void)
  {
  	DR_copy    *self = (DR_copy *) palloc(sizeof(DR_copy));
  
  	self->pub.receiveSlot = copy_dest_receive;
  	self->pub.rStartup = copy_dest_startup;
  	self->pub.rShutdown = copy_dest_shutdown;
  	self->pub.rDestroy = copy_dest_destroy;
  	self->pub.mydest = DestCopyOut;
  
  	self->cstate = NULL;		/* will be set later */
  	self->processed = 0;
  
  	return (DestReceiver *) self;
  }
  