text: /* Preprocess only, using cpplib.
     Copyright (C) 1995-2017 Free Software Foundation, Inc.
     Written by Per Bothner, 1994-95.
  
     This program is free software; you can redistribute it and/or modify it
     under the terms of the GNU General Public License as published by the
     Free Software Foundation; either version 3, or (at your option) any
     later version.
  
     This program is distributed in the hope that it will be useful,
     but WITHOUT ANY WARRANTY; without even the implied warranty of
     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     GNU General Public License for more details.
  
     You should have received a copy of the GNU General Public License
     along with this program; see the file COPYING3.  If not see
     <http://www.gnu.org/licenses/>.  */
  
  #include "config.h"
  #include "system.h"
  #include "coretypes.h"
  #include "c-common.h"		/* For flags.  */
  #include "../libcpp/internal.h"
  #include "c-pragma.h"		/* For parse_in.  */
  
  /* Encapsulates state used to convert a stream of tokens into a text
     file.  */
  static struct
  {
    FILE *outf;			/* Stream to write to.  */
    const cpp_token *prev;	/* Previous token.  */
    const cpp_token *source;	/* Source token for spacing.  */
    int src_line;			/* Line number currently being written.  */
    bool printed;			/* True if something output at line.  */
    bool first_time;		/* pp_file_change hasn't been called yet.  */
    bool prev_was_system_token;	/* True if the previous token was a
  				   system token.*/
    const char *src_file;		/* Current source file.  */
  } print;
  
  /* Defined and undefined macros being queued for output with -dU at
     the next newline.  */
  struct macro_queue
  {
    struct macro_queue *next;	/* Next macro in the list.  */
    char *macro;			/* The name of the macro if not
  				   defined, the full definition if
  				   defined.  */
  };
  static macro_queue *define_queue, *undef_queue;
  
  /* General output routines.  */
  static void scan_translation_unit (cpp_reader *);
  static void print_lines_directives_only (int, const void *, size_t);
  static void scan_translation_unit_directives_only (cpp_reader *);
  static void scan_translation_unit_trad (cpp_reader *);
  static void account_for_newlines (const unsigned char *, size_t);
  static int dump_macro (cpp_reader *, cpp_hashnode *, void *);
  static void dump_queued_macros (cpp_reader *);
  
  static bool print_line_1 (source_location, const char*, FILE *);
  static bool print_line (source_location, const char *);
  static bool maybe_print_line_1 (source_location, FILE *);
  static bool maybe_print_line (source_location);
  static bool do_line_change (cpp_reader *, const cpp_token *,
  			    source_location, int);
  
  /* Callback routines for the parser.   Most of these are active only
     in specific modes.  */
  static void cb_line_change (cpp_reader *, const cpp_token *, int);
  static void cb_define (cpp_reader *, source_location, cpp_hashnode *);
  static void cb_undef (cpp_reader *, source_location, cpp_hashnode *);
  static void cb_used_define (cpp_reader *, source_location, cpp_hashnode *);
  static void cb_used_undef (cpp_reader *, source_location, cpp_hashnode *);
  static void cb_include (cpp_reader *, source_location, const unsigned char *,
  			const char *, int, const cpp_token **);
  static void cb_ident (cpp_reader *, source_location, const cpp_string *);
  static void cb_def_pragma (cpp_reader *, source_location);
  static void cb_read_pch (cpp_reader *pfile, const char *name,
  			 int fd, const char *orig_name);
  
  /* Preprocess and output.  */
  void
  preprocess_file (cpp_reader *pfile)
  {
    /* A successful cpp_read_main_file guarantees that we can call
       cpp_scan_nooutput or cpp_get_token next.  */
    if (flag_no_output && pfile->buffer)
      {
        /* Scan -included buffers, then the main file.  */
        while (pfile->buffer->prev)
  	cpp_scan_nooutput (pfile);
        cpp_scan_nooutput (pfile);
      }
    else if (cpp_get_options (pfile)->traditional)
      scan_translation_unit_trad (pfile);
    else if (cpp_get_options (pfile)->directives_only
  	   && !cpp_get_options (pfile)->preprocessed)
      scan_translation_unit_directives_only (pfile);
    else
      scan_translation_unit (pfile);
  
    /* -dM command line option.  Should this be elsewhere?  */
    if (flag_dump_macros == 'M')
      cpp_forall_identifiers (pfile, dump_macro, NULL);
  
    /* Flush any pending output.  */
    if (print.printed)
      putc ('\n', print.outf);
  }
  
  /* Set up the callbacks as appropriate.  */
  void
  init_pp_output (FILE *out_stream)
  {
    cpp_callbacks *cb = cpp_get_callbacks (parse_in);
  
    if (!flag_no_output)
      {
        cb->line_change = cb_line_change;
        /* Don't emit #pragma or #ident directives if we are processing
  	 assembly language; the assembler may choke on them.  */
        if (cpp_get_options (parse_in)->lang != CLK_ASM)
  	{
  	  cb->ident      = cb_ident;
  	  cb->def_pragma = cb_def_pragma;
  	}
      }
  
    if (flag_dump_includes)
      cb->include  = cb_include;
  
    if (flag_pch_preprocess)
      {
        cb->valid_pch = c_common_valid_pch;
        cb->read_pch = cb_read_pch;
      }
  
    if (flag_dump_macros == 'N' || flag_dump_macros == 'D')
      {
        cb->define = cb_define;
        cb->undef  = cb_undef;
      }
  
    if (flag_dump_macros == 'U')
      {
        cb->before_define = dump_queued_macros;
        cb->used_define = cb_used_define;
        cb->used_undef = cb_used_undef;
      }
  
    cb->has_attribute = c_common_has_attribute;
    cb->get_source_date_epoch = cb_get_source_date_epoch;
  
    /* Initialize the print structure.  */
    print.src_line = 1;
    print.printed = false;
    print.prev = 0;
    print.outf = out_stream;
    print.first_time = 1;
    print.src_file = "";
    print.prev_was_system_token = false;
  }
  
  /* Writes out the preprocessed file, handling spacing and paste
     avoidance issues.  */
  static void
  scan_translation_unit (cpp_reader *pfile)
  {
    bool avoid_paste = false;
    bool do_line_adjustments
      = cpp_get_options (parse_in)->lang != CLK_ASM
        && !flag_no_line_commands;
    bool in_pragma = false;
    bool line_marker_emitted = false;
  
    print.source = NULL;
    for (;;)
      {
        source_location loc;
        const cpp_token *token = cpp_get_token_with_location (pfile, &loc);
  
        if (token->type == CPP_PADDING)
  	{
  	  avoid_paste = true;
  	  if (print.source == NULL
  	      || (!(print.source->flags & PREV_WHITE)
  		  && token->val.source == NULL))
  	    print.source = token->val.source;
  	  continue;
  	}
  
        if (token->type == CPP_EOF)
  	break;
  
        /* Subtle logic to output a space if and only if necessary.  */
        if (avoid_paste)
  	{
  	  int src_line = LOCATION_LINE (loc);
  
  	  if (print.source == NULL)
  	    print.source = token;
  
  	  if (src_line != print.src_line
  	      && do_line_adjustments
  	      && !in_pragma)
  	    {
  	      line_marker_emitted = do_line_change (pfile, token, loc, false);
  	      putc (' ', print.outf);
  	      print.printed = true;
  	    }
  	  else if (print.source->flags & PREV_WHITE
  		   || (print.prev
  		       && cpp_avoid_paste (pfile, print.prev, token))
  		   || (print.prev == NULL && token->type == CPP_HASH))
  	    {
  	      putc (' ', print.outf);
  	      print.printed = true;
  	    }
  	}
        else if (token->flags & PREV_WHITE)
  	{
  	  int src_line = LOCATION_LINE (loc);
  
  	  if (src_line != print.src_line
  	      && do_line_adjustments
  	      && !in_pragma)
  	    line_marker_emitted = do_line_change (pfile, token, loc, false);
  	  putc (' ', print.outf);
  	  print.printed = true;
  	}
  
        avoid_paste = false;
        print.source = NULL;
        print.prev = token;
        if (token->type == CPP_PRAGMA)
  	{
  	  const char *space;
  	  const char *name;
  
  	  line_marker_emitted = maybe_print_line (token->src_loc);
  	  fputs ("#pragma ", print.outf);
  	  c_pp_lookup_pragma (token->val.pragma, &space, &name);
  	  if (space)
  	    fprintf (print.outf, "%s %s", space, name);
  	  else
  	    fprintf (print.outf, "%s", name);
  	  print.printed = true;
  	  in_pragma = true;
  	}
        else if (token->type == CPP_PRAGMA_EOL)
  	{
  	  maybe_print_line (token->src_loc);
  	  in_pragma = false;
  	}
        else
  	{
  	  if (cpp_get_options (parse_in)->debug)
  	    linemap_dump_location (line_table, token->src_loc, print.outf);
  
  	  if (do_line_adjustments
  	      && !in_pragma
  	      && !line_marker_emitted
  	      && print.prev_was_system_token != !!in_system_header_at (loc)
  	      && !is_location_from_builtin_token (loc))
  	    /* The system-ness of this token is different from the one
  	       of the previous token.  Let's emit a line change to
  	       mark the new system-ness before we emit the token.  */
  	    {
  	      do_line_change (pfile, token, loc, false);
  	      print.prev_was_system_token = !!in_system_header_at (loc);
  	    }
  	  cpp_output_token (token, print.outf);
  	  line_marker_emitted = false;
  	  print.printed = true;
  	}
  
        /* CPP_COMMENT tokens and raw-string literal tokens can
  	 have embedded new-line characters.  Rather than enumerating
  	 all the possible token types just check if token uses
  	 val.str union member.  */
        if (cpp_token_val_index (token) == CPP_TOKEN_FLD_STR)
  	account_for_newlines (token->val.str.text, token->val.str.len);
      }
  }
  
  static void
  print_lines_directives_only (int lines, const void *buf, size_t size)
  {
    print.src_line += lines;
    fwrite (buf, 1, size, print.outf);
  }
  
  /* Writes out the preprocessed file, handling spacing and paste
     avoidance issues.  */
  static void
  scan_translation_unit_directives_only (cpp_reader *pfile)
  {
    struct _cpp_dir_only_callbacks cb;
  
    cb.print_lines = print_lines_directives_only;
    cb.maybe_print_line = (void (*) (source_location)) maybe_print_line;
  
    _cpp_preprocess_dir_only (pfile, &cb);
  }
  
  /* Adjust print.src_line for newlines embedded in output.  */
  static void
  account_for_newlines (const unsigned char *str, size_t len)
  {
    while (len--)
      if (*str++ == '\n')
        print.src_line++;
  }
  
  /* Writes out a traditionally preprocessed file.  */
  static void
  scan_translation_unit_trad (cpp_reader *pfile)
  {
    while (_cpp_read_logical_line_trad (pfile))
      {
        size_t len = pfile->out.cur - pfile->out.base;
        maybe_print_line (pfile->out.first_line);
        fwrite (pfile->out.base, 1, len, print.outf);
        print.printed = true;
        if (!CPP_OPTION (pfile, discard_comments))
  	account_for_newlines (pfile->out.base, len);
      }
  }
  
  /* If the token read on logical line LINE needs to be output on a
     different line to the current one, output the required newlines or
     a line marker.  If a line marker was emitted, return TRUE otherwise
     return FALSE.  */
  
  static bool
  maybe_print_line_1 (source_location src_loc, FILE *stream)
  {
    bool emitted_line_marker = false;
    int src_line = LOCATION_LINE (src_loc);
    const char *src_file = LOCATION_FILE (src_loc);
  
    /* End the previous line of text.  */
    if (print.printed)
      {
        putc ('\n', stream);
        print.src_line++;
        print.printed = false;
      }
  
    if (!flag_no_line_commands
        && src_line >= print.src_line
        && src_line < print.src_line + 8
        && strcmp (src_file, print.src_file) == 0)
      {
        while (src_line > print.src_line)
  	{
  	  putc ('\n', stream);
  	  print.src_line++;
  	}
      }
    else
      emitted_line_marker = print_line_1 (src_loc, "", stream);
  
    return emitted_line_marker;
  }
  
  /* If the token read on logical line LINE needs to be output on a
     different line to the current one, output the required newlines or
     a line marker.  If a line marker was emitted, return TRUE otherwise
     return FALSE.  */
  
  static bool
  maybe_print_line (source_location src_loc)
  {
    if (cpp_get_options (parse_in)->debug)
      linemap_dump_location (line_table, src_loc,
  			   print.outf);
    return maybe_print_line_1 (src_loc, print.outf);
  }
  
  /* Output a line marker for logical line LINE.  Special flags are "1"
     or "2" indicating entering or leaving a file.  If the line marker
     was effectively emitted, return TRUE otherwise return FALSE.  */
  
  static bool
  print_line_1 (source_location src_loc, const char *special_flags, FILE *stream)
  {
    bool emitted_line_marker = false;
  
    /* End any previous line of text.  */
    if (print.printed)
      putc ('\n', stream);
    print.printed = false;
  
    if (!flag_no_line_commands)
      {
        const char *file_path = LOCATION_FILE (src_loc);
        int sysp;
        size_t to_file_len = strlen (file_path);
        unsigned char *to_file_quoted =
           (unsigned char *) alloca (to_file_len * 4 + 1);
        unsigned char *p;
  
        print.src_line = LOCATION_LINE (src_loc);
        print.src_file = file_path;
  
        /* cpp_quote_string does not nul-terminate, so we have to do it
  	 ourselves.  */
        p = cpp_quote_string (to_file_quoted,
  			    (const unsigned char *) file_path,
  			    to_file_len);
        *p = '\0';
        fprintf (stream, "# %u \"%s\"%s",
  	       print.src_line == 0 ? 1 : print.src_line,
  	       to_file_quoted, special_flags);
  
        sysp = in_system_header_at (src_loc);
        if (sysp == 2)
  	fputs (" 3 4", stream);
        else if (sysp == 1)
  	fputs (" 3", stream);
  
        putc ('\n', stream);
        emitted_line_marker = true;
      }
  
    return emitted_line_marker;
  }
  
  /* Output a line marker for logical line LINE.  Special flags are "1"
     or "2" indicating entering or leaving a file.  Return TRUE if a
     line marker was effectively emitted, FALSE otherwise.  */
  
  static bool
  print_line (source_location src_loc, const char *special_flags)
  {
      if (cpp_get_options (parse_in)->debug)
        linemap_dump_location (line_table, src_loc,
  			     print.outf);
      return print_line_1 (src_loc, special_flags, print.outf);
  }
  
  /* Helper function for cb_line_change and scan_translation_unit.
     Return TRUE if a line marker is emitted, FALSE otherwise.  */
  static bool
  do_line_change (cpp_reader *pfile, const cpp_token *token,
  		source_location src_loc, int parsing_args)
  {
    bool emitted_line_marker = false;
    if (define_queue || undef_queue)
      dump_queued_macros (pfile);
  
    if (token->type == CPP_EOF || parsing_args)
      return false;
  
    emitted_line_marker = maybe_print_line (src_loc);
    print.prev = 0;
    print.source = 0;
  
    /* Supply enough spaces to put this token in its original column,
       one space per column greater than 2, since scan_translation_unit
       will provide a space if PREV_WHITE.  Don't bother trying to
       reconstruct tabs; we can't get it right in general, and nothing
       ought to care.  Some things do care; the fault lies with them.  */
    if (!CPP_OPTION (pfile, traditional))
      {
        int spaces = LOCATION_COLUMN (src_loc) - 2;
        print.printed = true;
  
        while (-- spaces >= 0)
  	putc (' ', print.outf);
      }
  
    return emitted_line_marker;
  }
  
  /* Called when a line of output is started.  TOKEN is the first token
     of the line, and at end of file will be CPP_EOF.  */
  static void
  cb_line_change (cpp_reader *pfile, const cpp_token *token,
  		int parsing_args)
  {
    do_line_change (pfile, token, token->src_loc, parsing_args);
  }
  
  static void
  cb_ident (cpp_reader *pfile ATTRIBUTE_UNUSED, source_location line,
  	  const cpp_string *str)
  {
    maybe_print_line (line);
    fprintf (print.outf, "#ident %s\n", str->text);
    print.src_line++;
  }
  
  static void
  cb_define (cpp_reader *pfile, source_location line, cpp_hashnode *node)
  {
    const line_map_ordinary *map;
  
    maybe_print_line (line);
    fputs ("#define ", print.outf);
  
    /* 'D' is whole definition; 'N' is name only.  */
    if (flag_dump_macros == 'D')
      fputs ((const char *) cpp_macro_definition (pfile, node),
  	   print.outf);
    else
      fputs ((const char *) NODE_NAME (node), print.outf);
  
    putc ('\n', print.outf);
    print.printed = false;
    linemap_resolve_location (line_table, line,
  			    LRK_MACRO_DEFINITION_LOCATION,
  			    &map);
    if (LINEMAP_LINE (map) != 0)
      print.src_line++;
  }
  
  static void
  cb_undef (cpp_reader *pfile ATTRIBUTE_UNUSED, source_location line,
  	  cpp_hashnode *node)
  {
    maybe_print_line (line);
    fprintf (print.outf, "#undef %s\n", NODE_NAME (node));
    print.src_line++;
  }
  
  static void
  cb_used_define (cpp_reader *pfile, source_location line ATTRIBUTE_UNUSED,
  		cpp_hashnode *node)
  {
    macro_queue *q;
    if (node->flags & NODE_BUILTIN)
      return;
    q = XNEW (macro_queue);
    q->macro = xstrdup ((const char *) cpp_macro_definition (pfile, node));
    q->next = define_queue;
    define_queue = q;
  }
  
  static void
  cb_used_undef (cpp_reader *pfile ATTRIBUTE_UNUSED,
  	       source_location line ATTRIBUTE_UNUSED,
  	       cpp_hashnode *node)
  {
    macro_queue *q;
    q = XNEW (macro_queue);
    q->macro = xstrdup ((const char *) NODE_NAME (node));
    q->next = undef_queue;
    undef_queue = q;
  }
  
  static void
  dump_queued_macros (cpp_reader *pfile ATTRIBUTE_UNUSED)
  {
    macro_queue *q;
  
    /* End the previous line of text.  */
    if (print.printed)
      {
        putc ('\n', print.outf);
        print.src_line++;
        print.printed = false;
      }
  
    for (q = define_queue; q;)
      {
        macro_queue *oq;
        fputs ("#define ", print.outf);
        fputs (q->macro, print.outf);
        putc ('\n', print.outf);
        print.printed = false;
        print.src_line++;
        oq = q;
        q = q->next;
        free (oq->macro);
        free (oq);
      }
    define_queue = NULL;
    for (q = undef_queue; q;)
      {
        macro_queue *oq;
        fprintf (print.outf, "#undef %s\n", q->macro);
        print.src_line++;
        oq = q;
        q = q->next;
        free (oq->macro);
        free (oq);
      }
    undef_queue = NULL;
  }
  
  static void
  cb_include (cpp_reader *pfile ATTRIBUTE_UNUSED, source_location line,
  	    const unsigned char *dir, const char *header, int angle_brackets,
  	    const cpp_token **comments)
  {
    maybe_print_line (line);
    if (angle_brackets)
      fprintf (print.outf, "#%s <%s>", dir, header);
    else
      fprintf (print.outf, "#%s \"%s\"", dir, header);
  
    if (comments != NULL)
      {
        while (*comments != NULL)
  	{
  	  if ((*comments)->flags & PREV_WHITE)
  	    putc (' ', print.outf);
  	  cpp_output_token (*comments, print.outf);
  	  ++comments;
  	}
      }
  
    putc ('\n', print.outf);
    print.printed = false;
    print.src_line++;
  }
  
  /* Callback called when -fworking-director and -E to emit working
     directory in cpp output file.  */
  
  void
  pp_dir_change (cpp_reader *pfile ATTRIBUTE_UNUSED, const char *dir)
  {
    size_t to_file_len = strlen (dir);
    unsigned char *to_file_quoted =
       (unsigned char *) alloca (to_file_len * 4 + 1);
    unsigned char *p;
  
    /* cpp_quote_string does not nul-terminate, so we have to do it ourselves.  */
    p = cpp_quote_string (to_file_quoted, (const unsigned char *) dir, to_file_len);
    *p = '\0';
    fprintf (print.outf, "# 1 \"%s//\"\n", to_file_quoted);
  }
  
  /* The file name, line number or system header flags have changed, as
     described in MAP.  */
  
  void
  pp_file_change (const line_map_ordinary *map)
  {
    const char *flags = "";
  
    if (flag_no_line_commands)
      return;
  
    if (map != NULL)
      {
        input_location = map->start_location;
        if (print.first_time)
  	{
  	  /* Avoid printing foo.i when the main file is foo.c.  */
  	  if (!cpp_get_options (parse_in)->preprocessed)
  	    print_line (map->start_location, flags);
  	  print.first_time = 0;
  	}
        else
  	{
  	  /* Bring current file to correct line when entering a new file.  */
  	  if (map->reason == LC_ENTER)
  	    {
  	      const line_map_ordinary *from = INCLUDED_FROM (line_table, map);
  	      maybe_print_line (LAST_SOURCE_LINE_LOCATION (from));
  	    }
  	  if (map->reason == LC_ENTER)
  	    flags = " 1";
  	  else if (map->reason == LC_LEAVE)
  	    flags = " 2";
  	  print_line (map->start_location, flags);
  	}
      }
  }
  
  /* Copy a #pragma directive to the preprocessed output.  */
  static void
  cb_def_pragma (cpp_reader *pfile, source_location line)
  {
    maybe_print_line (line);
    fputs ("#pragma ", print.outf);
    cpp_output_line (pfile, print.outf);
    print.printed = false;
    print.src_line++;
  }
  
  /* Dump out the hash table.  */
  static int
  dump_macro (cpp_reader *pfile, cpp_hashnode *node, void *v ATTRIBUTE_UNUSED)
  {
    if (node->type == NT_MACRO && !(node->flags & NODE_BUILTIN))
      {
        fputs ("#define ", print.outf);
        fputs ((const char *) cpp_macro_definition (pfile, node),
  	     print.outf);
        putc ('\n', print.outf);
        print.printed = false;
        print.src_line++;
      }
  
    return 1;
  }
  
  /* Load in the PCH file NAME, open on FD.  It was originally searched for
     by ORIG_NAME.  Also, print out a #include command so that the PCH
     file can be loaded when the preprocessed output is compiled.  */
  
  static void
  cb_read_pch (cpp_reader *pfile, const char *name,
  	     int fd, const char *orig_name ATTRIBUTE_UNUSED)
  {
    c_common_read_pch (pfile, name, fd, orig_name);
  
    fprintf (print.outf, "#pragma GCC pch_preprocess \"%s\"\n", name);
    print.src_line++;
  }
  