1/* Specific flags and argument handling of the C preprocessor.
2 Copyright (C) 1999-2017 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