gcc/scan-decls.c

   1 /* scan-decls.c - Extracts declarations from cpp output.
   2    Copyright (C) 1993 Free Software Foundation, Inc.
   3
   4 This program is free software; you can redistribute it and/or modify it
   5 under the terms of the GNU General Public License as published by the
   6 Free Software Foundation; either version 2, or (at your option) any
   7 later version.
   8
   9 This program is distributed in the hope that it will be useful,
  10 but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 GNU General Public License for more details.
  13
  14 You should have received a copy of the GNU General Public License
  15 along with this program; if not, write to the Free Software
  16 Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
  17
  18    Written by Per Bothner <bothner@cygnus.com>, July 1993.  */
  19
  20 #include <stdio.h>
  21 #include <ctype.h>
  22 #include "hconfig.h"
  23 #include "cpplib.h"
  24
  25 int brace_nesting = 0;
  26
  27 /* The first extern_C_braces_length elements of extern_C_braces
  28    indicate the (brace nesting levels of) left braces that were
  29    prefixed by extern "C".  */
  30 int extern_C_braces_length = 0;
  31 char extern_C_braces[20];
  32 #define in_extern_C_brace (extern_C_braces_length>0)
  33
  34 /* True if the function declaration currently being scanned is
  35    prefixed by extern "C".  */
  36 int current_extern_C = 0;
  37
  38 static void
  39 skip_to_closing_brace (pfile)
  40      cpp_reader *pfile;
  41 {
  42   int nesting = 1;
  43   for (;;)
  44     {
  45       enum cpp_token token = cpp_get_token (pfile);
  46       if (token == CPP_EOF)
  47         break;
  48       if (token == CPP_LBRACE)
  49         nesting++;
  50       if (token == CPP_RBRACE && --nesting == 0)
  51         break;
  52     }
  53 }
  54
  55 /* This function scans a C source file (actually, the output of cpp),
  56    reading from FP.  It looks for function declarations, and certain
  57    other interesting sequences (external variables and macros).  */
  58
  59 int
  60 scan_decls (pfile, argc, argv)
  61      cpp_reader *pfile;
  62      int argc;
  63      char**argv;
  64 {
  65   int saw_extern, saw_inline;
  66   int old_written;
  67   int prev_id_start, prev_id_end;
  68   enum cpp_token token;
  69
  70
  71  new_statement:
  72   CPP_SET_WRITTEN (pfile, 0);
  73   token = cpp_get_token (pfile);
  74
  75  handle_statement:
  76   current_extern_C = 0;
  77   saw_extern = 0;
  78   saw_inline = 0;
  79   if (token == CPP_RBRACE)
  80     {
  81       /* Pop an 'extern "C"' nesting level, if appropriate.  */
  82       if (extern_C_braces_length
  83           && extern_C_braces[extern_C_braces_length - 1] == brace_nesting)
  84         extern_C_braces_length--;
  85       brace_nesting--;
  86       goto new_statement;
  87     }
  88   if (token == CPP_LBRACE)
  89     {
  90       brace_nesting++;
  91       goto new_statement;
  92     }
  93   if (token == CPP_EOF)
  94     return 0;
  95   if (token == CPP_SEMICOLON)
  96     goto new_statement;
  97   if (token != CPP_NAME)
  98     goto new_statement;
  99   if (strcmp (pfile->token_buffer, "inline") == 0)
 100      {
 101       saw_inline = 1;
 102       CPP_SET_WRITTEN (pfile, 0);
 103       token = cpp_get_non_space_token (pfile);
 104     }
 105   if (strcmp (pfile->token_buffer, "extern") == 0)
 106     {
 107       saw_extern = 1;
 108       CPP_SET_WRITTEN (pfile, 0);
 109       token = cpp_get_non_space_token (pfile);
 110       if (token == CPP_STRING
 111           && strcmp (pfile->token_buffer, "\"C\"") == 0)
 112         {
 113           CPP_SET_WRITTEN (pfile, 0);
 114           current_extern_C = 1;
 115           token = cpp_get_non_space_token (pfile);
 116           if (token == CPP_LPAREN)
 117             {
 118               brace_nesting++;
 119               extern_C_braces[extern_C_braces_length++] = brace_nesting;
 120               goto new_statement;
 121             }
 122           token = cpp_get_non_space_token (pfile);
 123         }
 124     }
 125   prev_id_start = NULL;
 126   for (;;)
 127     {
 128       int start_written = CPP_WRITTEN (pfile);
 129       token = cpp_get_token (pfile);
 130       switch (token)
 131         {
 132         case CPP_LPAREN:
 133           if (prev_id_start)
 134             {
 135               int nesting = 1;
 136               int have_arg_list = 0;
 137               cpp_buffer *fbuf = cpp_file_buffer (pfile);
 138               long func_lineno;
 139               cpp_buf_line_and_col (fbuf, &func_lineno, NULL);
 140               for (;;)
 141                 {
 142                   token = cpp_get_token (pfile);
 143                   if (token == CPP_LPAREN)
 144                     nesting++;
 145                   else if (token == CPP_RPAREN)
 146                     {
 147                       nesting--;
 148                       if (nesting == 0)
 149                         break;
 150                     }
 151                   else if (token == CPP_EOF)
 152                     break;
 153                   else if (token == CPP_NAME || token == CPP_3DOTS)
 154                     have_arg_list = 1;
 155                 }
 156               recognized_function (pfile->token_buffer + prev_id_start,
 157                                    prev_id_end - prev_id_start,
 158                                    (saw_inline ? 'I'
 159                                     : in_extern_C_brace || current_extern_C
 160                                     ? 'F' : 'f'),
 161                                    pfile->token_buffer, prev_id_start,
 162                                    have_arg_list,
 163                                    fbuf->nominal_fname, func_lineno);
 164               token = cpp_get_non_space_token (pfile);
 165               if (token == CPP_LBRACE)
 166                 {
 167                   /* skip body of (normally) inline function */
 168                   skip_to_closing_brace (pfile);
 169                   goto new_statement;
 170                 }
 171               goto handle_statement;
 172             }
 173           break;
 174         case CPP_SEMICOLON:
 175           if (prev_id_start && saw_extern)
 176             {
 177               recognized_extern (pfile->token_buffer + prev_id_start,
 178                                  prev_id_end - prev_id_start,
 179                                  pfile->token_buffer,
 180                                  prev_id_start);
 181             }
 182           goto new_statement;
 183         case CPP_NAME:
 184           prev_id_start = start_written;
 185           prev_id_end = CPP_WRITTEN (pfile);
 186           break;
 187
 188         case CPP_EOF:
 189           return;  /* ??? FIXME */
 190
 191         case CPP_LBRACE:  case CPP_RBRACE:  case CPP_DIRECTIVE:
 192           goto new_statement;  /* handle_statement? */
 193
 194         case CPP_HSPACE:  case CPP_VSPACE:  case CPP_COMMENT:  case CPP_POP:
 195           break;
 196
 197          default:
 198           prev_id_start = NULL;
 199         }
 200     }
 201 }