text: /*
   *	controldata.c
   *
   *	controldata functions
   *
   *	Copyright (c) 2010-2019, PostgreSQL Global Development Group
   *	src/bin/pg_upgrade/controldata.c
   */
  
  #include "postgres_fe.h"
  
  #include "pg_upgrade.h"
  #include "greenplum/pg_upgrade_greenplum.h"
  
  #include <ctype.h>
  
  /*
   * get_control_data()
   *
   * gets pg_control information in "ctrl". Assumes that bindir and
   * datadir are valid absolute paths to postgresql bin and pgdata
   * directories respectively *and* pg_resetwal is version compatible
   * with datadir. The main purpose of this function is to get pg_control
   * data in a version independent manner.
   *
   * The approach taken here is to invoke pg_resetwal with -n option
   * and then pipe its output. With little string parsing we get the
   * pg_control data.  pg_resetwal cannot be run while the server is running
   * so we use pg_controldata;  pg_controldata doesn't provide all the fields
   * we need to actually perform the upgrade, but it provides enough for
   * check mode.  We do not implement pg_resetwal -n because it is hard to
   * return valid xid data for a running server.
   */
  void
  get_control_data(ClusterInfo *cluster, bool live_check)
  {
  	char		cmd[MAXPGPATH];
  	char		bufin[MAX_STRING];
  	FILE	   *output;
  	char	   *p;
  	bool		got_tli = false;
  	bool		got_log_id = false;
  	bool		got_log_seg = false;
  	bool		got_xid = false;
  	bool		got_gxid = false;
  	bool		got_oid = false;
  	bool		got_multi = false;
  	bool		got_oldestmulti = false;
  	bool		got_mxoff = false;
  	bool		got_nextxlogfile = false;
  	bool		got_float8_pass_by_value = false;
  	bool		got_align = false;
  	bool		got_blocksz = false;
  	bool		got_largesz = false;
  	bool		got_walsz = false;
  	bool		got_walseg = false;
  	bool		got_ident = false;
  	bool		got_index = false;
  	bool		got_toast = false;
  	bool		got_large_object = false;
  	bool		got_date_is_int = false;
  	bool		got_data_checksum_version = false;
  	bool		got_cluster_state = false;
  	char	   *lc_collate = NULL;
  	char	   *lc_ctype = NULL;
  	char	   *lc_monetary = NULL;
  	char	   *lc_numeric = NULL;
  	char	   *lc_time = NULL;
  	char	   *lang = NULL;
  	char	   *language = NULL;
  	char	   *lc_all = NULL;
  	char	   *lc_messages = NULL;
  	uint32		tli = 0;
  	uint32		logid = 0;
  	uint32		segno = 0;
  	char	   *resetwal_bin;
  
  
  	/*
  	 * Because we test the pg_resetwal output as strings, it has to be in
  	 * English.  Copied from pg_regress.c.
  	 */
  	if (getenv("LC_COLLATE"))
  		lc_collate = pg_strdup(getenv("LC_COLLATE"));
  	if (getenv("LC_CTYPE"))
  		lc_ctype = pg_strdup(getenv("LC_CTYPE"));
  	if (getenv("LC_MONETARY"))
  		lc_monetary = pg_strdup(getenv("LC_MONETARY"));
  	if (getenv("LC_NUMERIC"))
  		lc_numeric = pg_strdup(getenv("LC_NUMERIC"));
  	if (getenv("LC_TIME"))
  		lc_time = pg_strdup(getenv("LC_TIME"));
  	if (getenv("LANG"))
  		lang = pg_strdup(getenv("LANG"));
  	if (getenv("LANGUAGE"))
  		language = pg_strdup(getenv("LANGUAGE"));
  	if (getenv("LC_ALL"))
  		lc_all = pg_strdup(getenv("LC_ALL"));
  	if (getenv("LC_MESSAGES"))
  		lc_messages = pg_strdup(getenv("LC_MESSAGES"));
  
  	pg_putenv("LC_COLLATE", NULL);
  	pg_putenv("LC_CTYPE", NULL);
  	pg_putenv("LC_MONETARY", NULL);
  	pg_putenv("LC_NUMERIC", NULL);
  	pg_putenv("LC_TIME", NULL);
  #ifndef WIN32
  	pg_putenv("LANG", NULL);
  #else
  	/* On Windows the default locale may not be English, so force it */
  	pg_putenv("LANG", "en");
  #endif
  	pg_putenv("LANGUAGE", NULL);
  	pg_putenv("LC_ALL", NULL);
  	pg_putenv("LC_MESSAGES", "C");
  
  	/*
  	 * Check for clean shutdown
  	 */
  	if (!live_check || cluster == &new_cluster)
  	{
  		/* only pg_controldata outputs the cluster state */
  		snprintf(cmd, sizeof(cmd), "\"%s/pg_controldata\" \"%s\"",
  				 cluster->bindir, cluster->pgdata);
  		fflush(stdout);
  		fflush(stderr);
  
  		if ((output = popen(cmd, "r")) == NULL)
  			pg_fatal("could not get control data using %s: %s\n",
  					 cmd, strerror(errno));
  
  		/* we have the result of cmd in "output". so parse it line by line now */
  		while (fgets(bufin, sizeof(bufin), output))
  		{
  			if ((p = strstr(bufin, "Database cluster state:")) != NULL)
  			{
  				p = strchr(p, ':');
  
  				if (p == NULL || strlen(p) <= 1)
  					pg_fatal("%d: database cluster state problem\n", __LINE__);
  
  				p++;			/* remove ':' char */
  
  				/*
  				 * We checked earlier for a postmaster lock file, and if we
  				 * found one, we tried to start/stop the server to replay the
  				 * WAL.  However, pg_ctl -m immediate doesn't leave a lock
  				 * file, but does require WAL replay, so we check here that
  				 * the server was shut down cleanly, from the controldata
  				 * perspective.
  				 */
  				/* remove leading spaces */
  				while (*p == ' ')
  					p++;
  				if (strcmp(p, "shut down in recovery\n") == 0)
  				{
  					if (cluster == &old_cluster)
  						pg_fatal("The source cluster was shut down while in recovery mode.  To upgrade, use \"rsync\" as documented or shut it down as a primary.\n");
  					else
  						pg_fatal("The target cluster was shut down while in recovery mode.  To upgrade, use \"rsync\" as documented or shut it down as a primary.\n");
  				}
  				else if (strcmp(p, "shut down\n") != 0)
  				{
  					if (cluster == &old_cluster)
  						pg_fatal("The source cluster was not shut down cleanly.\n");
  					else
  						pg_fatal("The target cluster was not shut down cleanly.\n");
  				}
  				got_cluster_state = true;
  			}
  		}
  
  		pclose(output);
  
  		if (!got_cluster_state)
  		{
  			if (cluster == &old_cluster)
  				pg_fatal("The source cluster lacks cluster state information:\n");
  			else
  				pg_fatal("The target cluster lacks cluster state information:\n");
  		}
  	}
  
  	/* pg_resetxlog has been renamed to pg_resetwal in version 10 */
  	if (GET_MAJOR_VERSION(cluster->bin_version) < 1000)
  		resetwal_bin = "pg_resetxlog\" -n";
  	else
  		resetwal_bin = "pg_resetwal\" -n";
  	snprintf(cmd, sizeof(cmd), "\"%s/%s \"%s\"",
  			 cluster->bindir,
  			 live_check ? "pg_controldata\"" : resetwal_bin,
  			 cluster->pgdata);
  	fflush(stdout);
  	fflush(stderr);
  
  	if ((output = popen(cmd, "r")) == NULL)
  		pg_fatal("could not get control data using %s: %s\n",
  				 cmd, strerror(errno));
  
  	/* Only in <= 8.3 */
  	if (GET_MAJOR_VERSION(cluster->major_version) <= 803)
  	{
  		cluster->controldata.float8_pass_by_value = false;
  		got_float8_pass_by_value = true;
  	}
  
  	/*
  	 * In PostgreSQL, checksums were introduced in 9.3 so the test for checksum
  	 * version in upstream applies to <= 9.2. Greenplum backported checksums
  	 * into 5.x which is based on PostgreSQL 8.3 so this test need to go
  	 * against 8.2 instead.
  	 */
  	if (GET_MAJOR_VERSION(cluster->major_version) == 802)
  	{
  		cluster->controldata.data_checksum_version = 0;
  		got_data_checksum_version = true;
  	}
  
  	/* we have the result of cmd in "output". so parse it line by line now */
  	while (fgets(bufin, sizeof(bufin), output))
  	{
  		pg_log(PG_VERBOSE, "%s", bufin);
  
  #ifdef WIN32
  
  		/*
  		 * Due to an installer bug, LANG=C doesn't work for PG 8.3.3, but does
  		 * work 8.2.6 and 8.3.7, so check for non-ASCII output and suggest a
  		 * minor upgrade.
  		 */
  		if (GET_MAJOR_VERSION(cluster->major_version) <= 803)
  		{
  			for (p = bufin; *p; p++)
  				if (!isascii((unsigned char) *p))
  					pg_fatal("The 8.3 cluster's pg_controldata is incapable of outputting ASCII, even\n"
  							 "with LANG=C.  You must upgrade this cluster to a newer version of PostgreSQL\n"
  							 "8.3 to fix this bug.  PostgreSQL 8.3.7 and later are known to work properly.\n");
  		}
  #endif
  
  		if ((p = strstr(bufin, "pg_control version number:")) != NULL)
  		{
  			p = strchr(p, ':');
  
  			if (p == NULL || strlen(p) <= 1)
  				pg_fatal("%d: pg_resetwal problem\n", __LINE__);
  
  			p++;				/* remove ':' char */
  			cluster->controldata.ctrl_ver = str2uint(p);
  		}
  		else if ((p = strstr(bufin, "Catalog version number:")) != NULL)
  		{
  			p = strchr(p, ':');
  
  			if (p == NULL || strlen(p) <= 1)
  				pg_fatal("%d: controldata retrieval problem\n", __LINE__);
  
  			p++;				/* remove ':' char */
  			cluster->controldata.cat_ver = str2uint(p);
  		}
  		else if ((p = strstr(bufin, "Latest checkpoint's TimeLineID:")) != NULL)
  		{
  			p = strchr(p, ':');
  
  			if (p == NULL || strlen(p) <= 1)
  				pg_fatal("%d: controldata retrieval problem\n", __LINE__);
  
  			p++;				/* remove ':' char */
  			tli = str2uint(p);
  			got_tli = true;
  		}
  		else if ((p = strstr(bufin, "First log file ID after reset:")) != NULL)
  		{
  			p = strchr(p, ':');
  
  			if (p == NULL || strlen(p) <= 1)
  				pg_fatal("%d: controldata retrieval problem\n", __LINE__);
  
  			p++;				/* remove ':' char */
  			logid = str2uint(p);
  			got_log_id = true;
  		}
  		else if ((p = strstr(bufin, "First log file segment after reset:")) != NULL)
  		{
  			p = strchr(p, ':');
  
  			if (p == NULL || strlen(p) <= 1)
  				pg_fatal("%d: controldata retrieval problem\n", __LINE__);
  
  			p++;				/* remove ':' char */
  			segno = str2uint(p);
  			got_log_seg = true;
  		}
  		/* GPDB 4.3 (and PostgreSQL 8.2) wording of the above two. */
  		else if ((p = strstr(bufin, "Current log file ID:")) != NULL)
  		{
  			p = strchr(p, ':');
  
  			if (p == NULL || strlen(p) <= 1)
  				pg_log(PG_FATAL, "%d: controldata retrieval problem\n", __LINE__);
  
  			p++;				/* removing ':' char */
  			logid = str2uint(p);
  			got_log_id = true;
  		}
  		else if ((p = strstr(bufin, "Next log file segment:")) != NULL)
  		{
  			p = strchr(p, ':');
  
  			if (p == NULL || strlen(p) <= 1)
  				pg_log(PG_FATAL, "%d: controldata retrieval problem\n", __LINE__);
  
  			p++;				/* removing ':' char */
  			segno = str2uint(p);
  			got_log_seg = true;
  		}
  		/*---*/
  		else if ((p = strstr(bufin, "Latest checkpoint's TimeLineID:")) != NULL)
  		{
  			p = strchr(p, ':');
  
  			if (p == NULL || strlen(p) <= 1)
  				pg_fatal("%d: controldata retrieval problem\n", __LINE__);
  
  			p++;				/* removing ':' char */
  			tli = str2uint(p);
  			got_tli = true;
  		}
  		else if ((p = strstr(bufin, "Latest checkpoint's NextXID:")) != NULL)
  		{
  			p = strchr(p, ':');
  
  			if (p == NULL || strlen(p) <= 1)
  				pg_fatal("%d: controldata retrieval problem\n", __LINE__);
  
  			p++;				/* remove ':' char */
  			cluster->controldata.chkpnt_nxtepoch = str2uint(p);
  
  			/*
  			 * Delimiter changed from '/' to ':' in 9.6.  We don't test for
  			 * the catalog version of the change because the catalog version
  			 * is pulled from pg_controldata too, and it isn't worth adding an
  			 * order dependency for this --- we just check the string.
  			 */
  			if (strchr(p, '/') != NULL)
  				p = strchr(p, '/');
  			else if (GET_MAJOR_VERSION(cluster->major_version) >= 906)
  				p = strchr(p, ':');
  			else
  				p = NULL;
  
  			if (p == NULL || strlen(p) <= 1)
  				pg_fatal("%d: controldata retrieval problem\n", __LINE__);
  
  			p++;				/* remove '/' or ':' char */
  			cluster->controldata.chkpnt_nxtxid = str2uint(p);
  			got_xid = true;
  		}
  		else if ((p = strstr(bufin, "Latest checkpoint's NextGxid:")) != NULL)
  		{
  			p = strchr(p, ':');
  
  			if (p == NULL || strlen(p) <= 1)
  				pg_fatal("%d: controldata retrieval problem\n", __LINE__);
  
  			p++;				/* remove ':' char */
  			cluster->controldata.chkpnt_nxtgxid = str2uint64(p);
  			got_gxid = true;
  		}
  		else if ((p = strstr(bufin, "Latest checkpoint's NextOID:")) != NULL)
  		{
  			p = strchr(p, ':');
  
  			if (p == NULL || strlen(p) <= 1)
  				pg_fatal("%d: controldata retrieval problem\n", __LINE__);
  
  			p++;				/* remove ':' char */
  			cluster->controldata.chkpnt_nxtoid = str2uint(p);
  			got_oid = true;
  		}
  		else if ((p = strstr(bufin, "Latest checkpoint's NextMultiXactId:")) != NULL)
  		{
  			p = strchr(p, ':');
  
  			if (p == NULL || strlen(p) <= 1)
  				pg_fatal("%d: controldata retrieval problem\n", __LINE__);
  
  			p++;				/* remove ':' char */
  			cluster->controldata.chkpnt_nxtmulti = str2uint(p);
  			got_multi = true;
  		}
  		else if ((p = strstr(bufin, "Latest checkpoint's oldestMultiXid:")) != NULL)
  		{
  			p = strchr(p, ':');
  
  			if (p == NULL || strlen(p) <= 1)
  				pg_fatal("%d: controldata retrieval problem\n", __LINE__);
  
  			p++;				/* remove ':' char */
  			cluster->controldata.chkpnt_oldstMulti = str2uint(p);
  			got_oldestmulti = true;
  		}
  		else if ((p = strstr(bufin, "Latest checkpoint's NextMultiOffset:")) != NULL)
  		{
  			p = strchr(p, ':');
  
  			if (p == NULL || strlen(p) <= 1)
  				pg_fatal("%d: controldata retrieval problem\n", __LINE__);
  
  			p++;				/* remove ':' char */
  			cluster->controldata.chkpnt_nxtmxoff = str2uint(p);
  			got_mxoff = true;
  		}
  		else if ((p = strstr(bufin, "First log segment after reset:")) != NULL)
  		{
  			/* Skip the colon and any whitespace after it */
  			p = strchr(p, ':');
  			if (p == NULL || strlen(p) <= 1)
  				pg_fatal("%d: controldata retrieval problem\n", __LINE__);
  			p = strpbrk(p, "01234567890ABCDEF");
  			if (p == NULL || strlen(p) <= 1)
  				pg_fatal("%d: controldata retrieval problem\n", __LINE__);
  
  			/* Make sure it looks like a valid WAL file name */
  			if (strspn(p, "0123456789ABCDEF") != 24)
  				pg_fatal("%d: controldata retrieval problem\n", __LINE__);
  
  			strlcpy(cluster->controldata.nextxlogfile, p, 25);
  			got_nextxlogfile = true;
  		}
  		else if ((p = strstr(bufin, "Float8 argument passing:")) != NULL)
  		{
  			p = strchr(p, ':');
  
  			if (p == NULL || strlen(p) <= 1)
  				pg_fatal("%d: controldata retrieval problem\n", __LINE__);
  
  			p++;				/* remove ':' char */
  			/* used later for contrib check */
  			cluster->controldata.float8_pass_by_value = strstr(p, "by value") != NULL;
  			got_float8_pass_by_value = true;
  		}
  		else if ((p = strstr(bufin, "Maximum data alignment:")) != NULL)
  		{
  			p = strchr(p, ':');
  
  			if (p == NULL || strlen(p) <= 1)
  				pg_fatal("%d: controldata retrieval problem\n", __LINE__);
  
  			p++;				/* remove ':' char */
  			cluster->controldata.align = str2uint(p);
  			got_align = true;
  		}
  		else if ((p = strstr(bufin, "Database block size:")) != NULL)
  		{
  			p = strchr(p, ':');
  
  			if (p == NULL || strlen(p) <= 1)
  				pg_fatal("%d: controldata retrieval problem\n", __LINE__);
  
  			p++;				/* remove ':' char */
  			cluster->controldata.blocksz = str2uint(p);
  			got_blocksz = true;
  		}
  		else if ((p = strstr(bufin, "Blocks per segment of large relation:")) != NULL)
  		{
  			p = strchr(p, ':');
  
  			if (p == NULL || strlen(p) <= 1)
  				pg_fatal("%d: controldata retrieval problem\n", __LINE__);
  
  			p++;				/* remove ':' char */
  			cluster->controldata.largesz = str2uint(p);
  			got_largesz = true;
  		}
  		else if ((p = strstr(bufin, "WAL block size:")) != NULL)
  		{
  			p = strchr(p, ':');
  
  			if (p == NULL || strlen(p) <= 1)
  				pg_fatal("%d: controldata retrieval problem\n", __LINE__);
  
  			p++;				/* remove ':' char */
  			cluster->controldata.walsz = str2uint(p);
  			got_walsz = true;
  		}
  		else if ((p = strstr(bufin, "Bytes per WAL segment:")) != NULL)
  		{
  			p = strchr(p, ':');
  
  			if (p == NULL || strlen(p) <= 1)
  				pg_fatal("%d: controldata retrieval problem\n", __LINE__);
  
  			p++;				/* remove ':' char */
  			cluster->controldata.walseg = str2uint(p);
  			got_walseg = true;
  		}
  		else if ((p = strstr(bufin, "Maximum length of identifiers:")) != NULL)
  		{
  			p = strchr(p, ':');
  
  			if (p == NULL || strlen(p) <= 1)
  				pg_fatal("%d: controldata retrieval problem\n", __LINE__);
  
  			p++;				/* remove ':' char */
  			cluster->controldata.ident = str2uint(p);
  			got_ident = true;
  		}
  		else if ((p = strstr(bufin, "Maximum columns in an index:")) != NULL)
  		{
  			p = strchr(p, ':');
  
  			if (p == NULL || strlen(p) <= 1)
  				pg_fatal("%d: controldata retrieval problem\n", __LINE__);
  
  			p++;				/* remove ':' char */
  			cluster->controldata.index = str2uint(p);
  			got_index = true;
  		}
  		else if ((p = strstr(bufin, "Maximum size of a TOAST chunk:")) != NULL)
  		{
  			p = strchr(p, ':');
  
  			if (p == NULL || strlen(p) <= 1)
  				pg_fatal("%d: controldata retrieval problem\n", __LINE__);
  
  			p++;				/* remove ':' char */
  			cluster->controldata.toast = str2uint(p);
  			got_toast = true;
  		}
  		else if ((p = strstr(bufin, "Size of a large-object chunk:")) != NULL)
  		{
  			p = strchr(p, ':');
  
  			if (p == NULL || strlen(p) <= 1)
  				pg_fatal("%d: controldata retrieval problem\n", __LINE__);
  
  			p++;				/* remove ':' char */
  			cluster->controldata.large_object = str2uint(p);
  			got_large_object = true;
  		}
  		else if ((p = strstr(bufin, "Date/time type storage:")) != NULL)
  		{
  			p = strchr(p, ':');
  
  			if (p == NULL || strlen(p) <= 1)
  				pg_fatal("%d: controldata retrieval problem\n", __LINE__);
  
  			p++;				/* remove ':' char */
  			cluster->controldata.date_is_int = strstr(p, "64-bit integers") != NULL;
  			got_date_is_int = true;
  		}
  		else if ((p = strstr(bufin, "checksum")) != NULL)
  		{
  			p = strchr(p, ':');
  
  			if (p == NULL || strlen(p) <= 1)
  				pg_fatal("%d: controldata retrieval problem\n", __LINE__);
  
  			p++;				/* remove ':' char */
  			/* used later for contrib check */
  			cluster->controldata.data_checksum_version = str2uint(p);
  			got_data_checksum_version = true;
  		}
  	}
  
  	pclose(output);
  
  	/*
  	 * Restore environment variables
  	 */
  	pg_putenv("LC_COLLATE", lc_collate);
  	pg_putenv("LC_CTYPE", lc_ctype);
  	pg_putenv("LC_MONETARY", lc_monetary);
  	pg_putenv("LC_NUMERIC", lc_numeric);
  	pg_putenv("LC_TIME", lc_time);
  	pg_putenv("LANG", lang);
  	pg_putenv("LANGUAGE", language);
  	pg_putenv("LC_ALL", lc_all);
  	pg_putenv("LC_MESSAGES", lc_messages);
  
  	pg_free(lc_collate);
  	pg_free(lc_ctype);
  	pg_free(lc_monetary);
  	pg_free(lc_numeric);
  	pg_free(lc_time);
  	pg_free(lang);
  	pg_free(language);
  	pg_free(lc_all);
  	pg_free(lc_messages);
  
  	/*
  	 * Before 9.3, pg_resetwal reported the xlogid and segno of the first log
  	 * file after reset as separate lines. Starting with 9.3, it reports the
  	 * WAL file name. If the old cluster is older than 9.3, we construct the
  	 * WAL file name from the tli, xlogid, and segno.
  	 */
  	if (GET_MAJOR_VERSION(cluster->major_version) <= 902)
  	{
  		if (got_tli && got_log_id && got_log_seg)
  		{
  			snprintf(cluster->controldata.nextxlogfile, 25, "%08X%08X%08X",
  					 tli, logid, segno);
  			got_nextxlogfile = true;
  		}
  	}
  
  	/* verify that we got all the mandatory pg_control data */
  	if (!got_xid || !got_gxid || !got_oid ||
  		!got_multi ||
  		(!got_oldestmulti &&
  		 cluster->controldata.cat_ver >= MULTIXACT_FORMATCHANGE_CAT_VER) ||
  		!got_mxoff || (!live_check && !got_nextxlogfile) ||
  		!got_float8_pass_by_value || !got_align || !got_blocksz ||
  		!got_largesz || !got_walsz || !got_walseg || !got_ident ||
  		!got_index || /* !got_toast || */
  		(!got_large_object &&
  		 cluster->controldata.ctrl_ver >= LARGE_OBJECT_SIZE_PG_CONTROL_VER) ||
  		!got_date_is_int || !got_data_checksum_version)
  	{
  		if (cluster == &old_cluster)
  			pg_log(PG_REPORT,
  				   "The source cluster lacks some required control information:\n");
  		else
  			pg_log(PG_REPORT,
  				   "The target cluster lacks some required control information:\n");
  
  		if (!got_xid)
  			pg_log(PG_REPORT, "  checkpoint next XID\n");
  
  		if (!got_gxid)
  			pg_log(PG_REPORT, "  checkpoint next Gxid\n");
  
  		if (!got_oid)
  			pg_log(PG_REPORT, "  latest checkpoint next OID\n");
  
  		if (!got_multi)
  			pg_log(PG_REPORT, "  latest checkpoint next MultiXactId\n");
  
  		if (!got_oldestmulti &&
  			cluster->controldata.cat_ver >= MULTIXACT_FORMATCHANGE_CAT_VER)
  			pg_log(PG_REPORT, "  latest checkpoint oldest MultiXactId\n");
  
  		if (!got_mxoff)
  			pg_log(PG_REPORT, "  latest checkpoint next MultiXactOffset\n");
  
  		if (!live_check && !got_nextxlogfile)
  			pg_log(PG_REPORT, "  first WAL segment after reset\n");
  
  		if (!got_float8_pass_by_value)
  			pg_log(PG_REPORT, "  float8 argument passing method\n");
  
  		if (!got_align)
  			pg_log(PG_REPORT, "  maximum alignment\n");
  
  		if (!got_blocksz)
  			pg_log(PG_REPORT, "  block size\n");
  
  		if (!got_largesz)
  			pg_log(PG_REPORT, "  large relation segment size\n");
  
  		if (!got_walsz)
  			pg_log(PG_REPORT, "  WAL block size\n");
  
  		if (!got_walseg)
  			pg_log(PG_REPORT, "  WAL segment size\n");
  
  		if (!got_ident)
  			pg_log(PG_REPORT, "  maximum identifier length\n");
  
  		if (!got_index)
  			pg_log(PG_REPORT, "  maximum number of indexed columns\n");
  
  #if 0	/* not mandatory in GPDB, see comment in check_control_data() */
  		if (!got_toast)
  			pg_log(PG_REPORT, "  maximum TOAST chunk size\n");
  #endif
  
  		if (!got_large_object &&
  			cluster->controldata.ctrl_ver >= LARGE_OBJECT_SIZE_PG_CONTROL_VER)
  			pg_log(PG_REPORT, "  large-object chunk size\n");
  
  		if (!got_date_is_int)
  			pg_log(PG_REPORT, "  dates/times are integers?\n");
  
  		/* value added in Postgres 8.4 */
  		if (!got_float8_pass_by_value)
  			pg_log(PG_REPORT, "  float8 argument passing method\n");
  
  		/* value added in Postgres 9.3 */
  		if (!got_data_checksum_version)
  			pg_log(PG_REPORT, "  data checksum version\n");
  
  		pg_fatal("Cannot continue without required control information, terminating\n");
  	}
  }
  
  
  /*
   * check_control_data()
   *
   * check to make sure the control data settings are compatible
   */
  void
  check_control_data(ControlData *oldctrl,
  				   ControlData *newctrl)
  {
  	if (oldctrl->align == 0 || oldctrl->align != newctrl->align)
  		pg_fatal("old and new pg_controldata alignments are invalid or do not match\n"
  				 "Likely one cluster is a 32-bit install, the other 64-bit\n");
  
  	if (oldctrl->blocksz == 0 || oldctrl->blocksz != newctrl->blocksz)
  		pg_fatal("old and new pg_controldata block sizes are invalid or do not match\n");
  
  	if (oldctrl->largesz == 0 || oldctrl->largesz != newctrl->largesz)
  		pg_fatal("old and new pg_controldata maximum relation segment sizes are invalid or do not match\n");
  
  	if (oldctrl->walsz == 0 || oldctrl->walsz != newctrl->walsz)
  		pg_fatal("old and new pg_controldata WAL block sizes are invalid or do not match\n");
  
  	if (oldctrl->walseg == 0 || oldctrl->walseg != newctrl->walseg)
  		pg_fatal("old and new pg_controldata WAL segment sizes are invalid or do not match\n");
  
  	if (oldctrl->ident == 0 || oldctrl->ident != newctrl->ident)
  		pg_fatal("old and new pg_controldata maximum identifier lengths are invalid or do not match\n");
  
  	if (oldctrl->index == 0 || oldctrl->index != newctrl->index)
  		pg_fatal("old and new pg_controldata maximum indexed columns are invalid or do not match\n");
  
  	/*
  	 * PostgreSQL's pg_upgrade checks for the maximum TOAST chunk size, because
  	 * the tuptoaster code assumes all chunks to have the same size. GPDB's
  	 * tuptoaster code has been modified to work with any chunk size, to
  	 * support upgrading from GPDB 4.3 to 5.0, because the chunk size was
  	 * changed between those releases (that is, between PostgreSQL 8.2 and
  	 * 8.3). Hence, 'got_toast' is not mandatory in GPDB.
  	 * TODO: Should we only consider got_toast not mandatory for upgrades to
  	 * 5.x?
  	 */
  	if (oldctrl->toast == 0 || oldctrl->toast != newctrl->toast)
  		pg_fatal("old and new pg_controldata maximum TOAST chunk sizes are invalid or do not match\n");
  
  	/* large_object added in 9.5, so it might not exist in the old cluster */
  	if (oldctrl->large_object != 0 &&
  		oldctrl->large_object != newctrl->large_object)
  		pg_fatal("old and new pg_controldata large-object chunk sizes are invalid or do not match\n");
  
  	/* 
  	 * GPDB, since 9.5, pg_upgrade removed the support for 8.3, however, GPDB
  	 * still keep it to support upgrading from GPDB 5
  	 */
  	if (oldctrl->date_is_int != newctrl->date_is_int)
  	{
  		pg_log(PG_WARNING,
  			   "\nOld and new pg_controldata date/time storage types do not match.\n");
  
  		/*
  		 * This is a common 8.3 -> 8.4 upgrade problem, so we are more verbose
  		 */
  		pg_fatal("You will need to rebuild the new server with configure option\n"
  				 "--disable-integer-datetimes or get server binaries built with those\n"
  				 "options.\n");
  	}
  
  	/*
  	 * float8_pass_by_value does not need to match, but is used in
  	 * check_for_isn_and_int8_passing_mismatch().
  	 */
  
  	/*
  	 * Check for allowed combinations of data checksums. PostgreSQL only allow
  	 * upgrades where the checksum settings match, in Greenplum we can however
  	 * set or remove checksums during the upgrade.
  	 */
  	if (oldctrl->data_checksum_version == 0 &&
  		newctrl->data_checksum_version != 0 &&
  		!is_checksum_mode(CHECKSUM_ADD))
  		pg_fatal("old cluster does not use data checksums but the new one does\n");
  	else if (oldctrl->data_checksum_version != 0 &&
  			 newctrl->data_checksum_version == 0 &&
  			 !is_checksum_mode(CHECKSUM_REMOVE))
  		pg_fatal("old cluster uses data checksums but the new one does not\n");
  	else if (oldctrl->data_checksum_version == newctrl->data_checksum_version &&
  			 !is_checksum_mode(CHECKSUM_NONE))
  		pg_fatal("old and new cluster data checksum configuration match, cannot %s data checksums\n",
  				 (is_checksum_mode(CHECKSUM_ADD) ? "add" : "remove"));
  	else if (oldctrl->data_checksum_version != 0 && is_checksum_mode(CHECKSUM_ADD))
  		pg_fatal("--add-checksum option not supported for old cluster which uses data checksums\n");
  	else if (oldctrl->data_checksum_version != newctrl->data_checksum_version
  			 && is_checksum_mode(CHECKSUM_NONE))
  		pg_fatal("old and new cluster pg_controldata checksum versions do not match\n");
  }
  
  
  void
  disable_old_cluster(void)
  {
  	char		old_path[MAXPGPATH],
  				new_path[MAXPGPATH];
  
  	/* rename pg_control so old server cannot be accidentally started */
  	prep_status("Adding \".old\" suffix to old global/pg_control");
  
  	snprintf(old_path, sizeof(old_path), "%s/global/pg_control", old_cluster.pgdata);
  	snprintf(new_path, sizeof(new_path), "%s/global/pg_control.old", old_cluster.pgdata);
  	if (pg_mv_file(old_path, new_path) != 0)
  		pg_fatal("Unable to rename %s to %s.\n", old_path, new_path);
  	check_ok();
  
  	pg_log(PG_REPORT, "\n"
  		   "If you want to start the old cluster, you will need to remove\n"
  		   "the \".old\" suffix from %s/global/pg_control.old.\n"
  		   "Because \"link\" mode was used, the old cluster cannot be safely\n"
  		   "started once the new cluster has been started.\n\n", old_cluster.pgdata);
  }
  