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 "scan.h"
  24
  25 sstring buf;
  26 sstring rtype;
  27 sstring arg_list;
  28
  29 int brace_nesting = 0;
  30
  31 /* The first extern_C_braces_length elements of extern_C_braces
  32    indicate the (brace nesting levels of) left braces that were
  33    prefixed by extern "C".  */
  34 int extern_C_braces_length = 0;
  35 char extern_C_braces[20];
  36 #define in_extern_C_brace (extern_C_braces_length>0)
  37
  38 /* True if the function declaration currently being scanned is
  39    prefixed by extern "C".  */
  40 int current_extern_C = 0;
  41
  42 static void
  43 skip_to_closing_brace (fp)
  44      FILE *fp;
  45 {
  46   int nesting = 1;
  47   for (;;)
  48     {
  49       int c = get_token (fp, &buf);
  50       if (c == EOF)
  51         break;
  52       if (c == '{')
  53         nesting++;
  54       if (c == '}' && --nesting == 0)
  55         break;
  56     }
  57 }
  58
  59 /* This function scans a C source file (actually, the output of cpp),
  60    reading from FP.  It looks for function declarations, and certain
  61    other interesting sequences (external variables and macros).  */
  62
  63 int
  64 scan_decls (fp)
  65      FILE *fp;
  66 {
  67   int c;
  68   int saw_extern, saw_inline;
  69
  70  new_statement:
  71   c = get_token (fp, &buf);
  72  handle_statement:
  73   current_extern_C = 0;
  74   saw_extern = 0;
  75   saw_inline = 0;
  76   if (c == '}')
  77     {
  78       /* Pop an 'extern "C"' nesting level, if appropriate.  */
  79       if (extern_C_braces_length
  80           && extern_C_braces[extern_C_braces_length - 1] == brace_nesting)
  81         extern_C_braces_length--;
  82       brace_nesting--;
  83       goto new_statement;
  84     }
  85   if (c == '{')
  86     {
  87       brace_nesting++;
  88       goto new_statement;
  89     }
  90   if (c == EOF)
  91     return 0;
  92   if (c == ';')
  93     goto new_statement;
  94   if (c != IDENTIFIER_TOKEN)
  95     goto new_statement;
  96   rtype.ptr = rtype.base;
  97   if (SSTRING_LENGTH (&buf) > 16
  98       && strncmp (buf.base, "__DEFINED_MACRO_", 16) == 0)
  99     {
 100       /* For certain interesting macro names, fixproto puts
 101          #ifdef FOO
 102          __DEFINED_MACRO_FOO
 103          #endif
 104          into the file to be pre-processed.  So if we see __DEFINED_MACRO_FOO,
 105          it means FOO was defined, which we may want to make a note of.  */
 106       recognized_macro (buf.base+16);
 107       goto new_statement;
 108     }
 109   if (strcmp (buf.base, "inline") == 0)
 110     {
 111       saw_inline = 1;
 112       c = get_token (fp, &buf);
 113     }
 114   if (strcmp (buf.base, "extern") == 0)
 115     {
 116       saw_extern = 1;
 117       c = get_token (fp, &buf);
 118       if (c == STRING_TOKEN && strcmp (buf.base, "C") == 0)
 119         {
 120           current_extern_C = 1;
 121           c = get_token (fp, &buf);
 122           if (c == '{')
 123             {
 124               brace_nesting++;
 125               extern_C_braces[extern_C_braces_length++] = brace_nesting;
 126               goto new_statement;
 127             }
 128           c = get_token (fp, &buf);
 129         }
 130     }
 131   for (;;)
 132     {
 133       int followingc = getc (fp); /* char following token in buf */
 134
 135       MAKE_SSTRING_SPACE (&rtype, 1);
 136       *rtype.ptr = 0;
 137
 138       if (c == IDENTIFIER_TOKEN)
 139         {
 140           int nextc = skip_spaces (fp, followingc);
 141           if (nextc == '(')
 142             {
 143               int nesting = 1;
 144               int func_lineno = source_lineno;
 145               char *args;
 146
 147               arg_list.ptr = arg_list.base;
 148               for (;;)
 149                 {
 150                   c = getc (fp);
 151                   if (c == '(')
 152                     nesting++;
 153                   else if (c == ')')
 154                     if (--nesting == 0)
 155                       break;
 156                   if (c == EOF)
 157                     break;
 158                   if (c == '\n')
 159                     {
 160                       c = ' ';
 161                       source_lineno++;
 162                       lineno++;
 163                     }
 164                   SSTRING_PUT (&arg_list, c);
 165                 }
 166               SSTRING_PUT (&arg_list, '\0');
 167               args = arg_list.base;
 168               while (*args == ' ')
 169                 args++;
 170               recognized_function (buf.base,
 171                                    (saw_inline ? 'I'
 172                                     : in_extern_C_brace || current_extern_C
 173                                     ? 'F' : 'f'),
 174                                    rtype.base, args,
 175                                    source_filename.base, func_lineno);
 176               c = get_token (fp, &buf);
 177               if (c == '{')
 178                 {
 179                   /* skip body of (normally) inline function */
 180                   skip_to_closing_brace (fp);
 181                   goto new_statement;
 182                 }
 183               goto handle_statement;
 184             }
 185           else if (nextc == ';' && saw_extern)
 186             {
 187               recognized_extern (buf.base, rtype.base);
 188               goto new_statement;
 189             }
 190           else
 191             ungetc (nextc, fp);
 192         }
 193       else if (followingc != EOF)
 194         ungetc (followingc, fp);
 195       if (c == ';' || c == '{' || c == '}' || c == EOF)
 196         goto handle_statement;
 197       sstring_append (&rtype, &buf);
 198       if (followingc == ' ' || followingc == '\t' || followingc == '\n')
 199         SSTRING_PUT (&rtype, ' ');
 200       c = get_token (fp, &buf);
 201     }
 202 }