1/* Specific flags and argument handling of the C preprocessor.
2   Copyright (C) 1999-2015 Free Software Foundation, Inc.
3
4This file is part of GCC.
5
6GCC is free software; you can redistribute it and/or modify it under
7the terms of the GNU General Public License as published by the Free
8Software Foundation; either version 3, or (at your option) any later
9version.
10
11GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12WARRANTY; without even the implied warranty of MERCHANTABILITY or
13FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14for more details.
15
16You should have received a copy of the GNU General Public License
17along 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.  */
37static 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.  */
46void
47lang_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.  */
193int 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.  */
199int lang_specific_extra_outfiles = 0;  /* Not used for cpp.  */
200