gcc/c-family/cppspec.c

   1 /* Specific flags and argument handling of the C preprocessor.
   2    Copyright (C) 1999-2018 Free Software Foundation, Inc.
   3
   4 This file is part of GCC.
   5
   6 GCC is free software; you can redistribute it and/or modify it under
   7 the terms of the GNU General Public License as published by the Free
   8 Software Foundation; either version 3, or (at your option) any later
   9 version.
  10
  11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14 for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GCC; see the file COPYING3.  If not see
  18 <http://www.gnu.org/licenses/>.  */
  19
  20 #include "config.h"
  21 #include "system.h"
  22 #include "coretypes.h"
  23 #include "tm.h"
  24 #include "gcc.h"
  25 #include "opts.h"
  26
  27 /* The `cpp' executable installed in $(bindir) and $(cpp_install_dir)
  28    is a customized version of the gcc driver.  It forces -E; -S and -c
  29    are errors.  It defaults to -x c for files with unrecognized
  30    extensions, unless -x options appear in argv, in which case we
  31    assume the user knows what they're doing.  If no explicit input is
  32    mentioned, it will read stdin.  */
  33
  34 /* Suffixes for known sorts of input files.  Note that we do not list
  35    files which are normally considered to have been preprocessed already,
  36    since the user's expectation is that `cpp' always preprocesses.  */
  37 static const char *const known_suffixes[] =
  38 {
  39   ".c",  ".C",   ".S",   ".m",
  40   ".cc", ".cxx", ".cpp", ".cp",  ".c++",
  41   ".sx",
  42   NULL
  43 };
  44
  45 /* Filter the command line before processing by the gcc driver proper.  */
  46 void
  47 lang_specific_driver (struct cl_decoded_option **in_decoded_options,
  48                       unsigned int *in_decoded_options_count,
  49                       int *in_added_libraries ATTRIBUTE_UNUSED)
  50 {
  51   struct cl_decoded_option *decoded_options = *in_decoded_options;
  52   unsigned int argc = *in_decoded_options_count;
  53
  54   /* Do we need to read stdin? */
  55   int read_stdin = 1;
  56
  57   /* Do we need to insert -E? */
  58   int need_E = 1;
  59
  60   /* Have we seen an input file? */
  61   int seen_input = 0;
  62
  63   /* Positions to insert -xc, -xassembler-with-cpp, and -o, if necessary.
  64      0 means unnecessary.  */
  65   unsigned int lang_c_here = 0;
  66   unsigned int lang_S_here = 0;
  67   unsigned int o_here = 0;
  68
  69   /* Do we need to fix up an input file with an unrecognized suffix? */
  70   int need_fixups = 1;
  71
  72   unsigned int i, j;
  73   struct cl_decoded_option *new_decoded_options;
  74   unsigned int new_argc;
  75   extern int is_cpp_driver;
  76
  77   is_cpp_driver = 1;
  78
  79   /* First pass.  If we see an -S or -c, barf.  If we see an input file,
  80      turn off read_stdin.  If we see a second input file, it is actually
  81      the output file.  If we see a third input file, barf.  */
  82   for (i = 1; i < argc; i++)
  83     {
  84       switch (decoded_options[i].opt_index)
  85         {
  86         case OPT_E:
  87           need_E = 0;
  88           break;
  89
  90         case OPT_S:
  91         case OPT_c:
  92           fatal_error (input_location,
  93                        "%qs is not a valid option to the preprocessor",
  94                        decoded_options[i].orig_option_with_args_text);
  95           return;
  96
  97         case OPT_x:
  98           need_fixups = 0;
  99           break;
 100
 101         case OPT_SPECIAL_input_file:
 102           {
 103             const char *file = decoded_options[i].arg;
 104
 105             if (strcmp (file, "-") == 0)
 106               read_stdin = 0;
 107             else
 108               {
 109                 seen_input++;
 110                 if (seen_input == 3)
 111                   {
 112                     fatal_error (input_location, "too many input files");
 113                     return;
 114                   }
 115                 else if (seen_input == 2)
 116                   {
 117                     o_here = i;
 118                   }
 119                 else
 120                   {
 121                     read_stdin = 0;
 122                     if (need_fixups)
 123                       {
 124                         int l = strlen (file);
 125                         int known = 0;
 126                         const char *const *suff;
 127
 128                         for (suff = known_suffixes; *suff; suff++)
 129                           if (!strcmp (*suff, &file[l - strlen(*suff)]))
 130                             {
 131                               known = 1;
 132                               break;
 133                             }
 134
 135                         if (! known)
 136                           {
 137                             /* .s files are a special case; we have to
 138                                treat them like .S files so
 139                                -D__ASSEMBLER__ will be in effect.  */
 140                             if (!strcmp (".s", &file[l - 2]))
 141                               lang_S_here = i;
 142                             else
 143                               lang_c_here = i;
 144                           }
 145                       }
 146                   }
 147               }
 148           }
 149           break;
 150         }
 151     }
 152
 153   /* If we don't need to edit the command line, we can bail early.  */
 154
 155   new_argc = argc + need_E + read_stdin + !!lang_c_here + !!lang_S_here;
 156
 157   if (new_argc == argc && !o_here)
 158     return;
 159
 160   new_decoded_options = XNEWVEC (struct cl_decoded_option, new_argc);
 161
 162   new_decoded_options[0] = decoded_options[0];
 163   j = 1;
 164
 165   if (need_E)
 166     generate_option (OPT_E, NULL, 1, CL_DRIVER, &new_decoded_options[j++]);
 167
 168   for (i = 1; i < argc; i++, j++)
 169     {
 170       if (i == lang_c_here)
 171         generate_option (OPT_x, "c", 1, CL_DRIVER, &new_decoded_options[j++]);
 172       else if (i == lang_S_here)
 173         generate_option (OPT_x, "assembler-with-cpp", 1, CL_DRIVER,
 174                          &new_decoded_options[j++]);
 175       else if (i == o_here)
 176         {
 177           generate_option (OPT_o, decoded_options[i].arg, 1, CL_DRIVER,
 178                            &new_decoded_options[j]);
 179           continue;
 180         }
 181
 182       new_decoded_options[j] = decoded_options[i];
 183     }
 184
 185   if (read_stdin)
 186     generate_option_input_file ("-", &new_decoded_options[j++]);
 187
 188   *in_decoded_options_count = new_argc;
 189   *in_decoded_options = new_decoded_options;
 190 }
 191
 192 /* Called before linking.  Returns 0 on success and -1 on failure.  */
 193 int lang_specific_pre_link (void)
 194 {
 195   return 0;  /* Not used for cpp.  */
 196 }
 197
 198 /* Number of extra output files that lang_specific_pre_link may generate.  */
 199 int lang_specific_extra_outfiles = 0;  /* Not used for cpp.  */