gcc/c-incpath.c

   1 /* Set up combined include path chain for the preprocessor.
   2    Copyright (C) 1986, 1987, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
   3    1999, 2000, 2001, 2002, 2003 Free Software Foundation, Inc.
   4
   5    Broken out of cppinit.c and cppfiles.c and rewritten Mar 2003.
   6
   7 This program is free software; you can redistribute it and/or modify it
   8 under the terms of the GNU General Public License as published by the
   9 Free Software Foundation; either version 2, or (at your option) any
  10 later version.
  11
  12 This program is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with this program; if not, write to the Free Software
  19 Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  20
  21 #include "config.h"
  22 #include "system.h"
  23 #include "coretypes.h"
  24 #include "tm.h"
  25 #include "cpplib.h"
  26 #include "prefix.h"
  27 #include "intl.h"
  28 #include "c-incpath.h"
  29 #include "cppdefault.h"
  30
  31 /* Windows does not natively support inodes, and neither does MSDOS.
  32    Cygwin's emulation can generate non-unique inodes, so don't use it.
  33    VMS has non-numeric inodes.  */
  34 #ifdef VMS
  35 # define INO_T_EQ(A, B) (!memcmp (&(A), &(B), sizeof (A)))
  36 # define INO_T_COPY(DEST, SRC) memcpy(&(DEST), &(SRC), sizeof (SRC))
  37 #else
  38 # if (defined _WIN32 && ! defined (_UWIN)) || defined __MSDOS__
  39 #  define INO_T_EQ(A, B) 0
  40 # else
  41 #  define INO_T_EQ(A, B) ((A) == (B))
  42 # endif
  43 # define INO_T_COPY(DEST, SRC) (DEST) = (SRC)
  44 #endif
  45
  46 static void add_env_var_paths (const char *, int);
  47 static void add_standard_paths (const char *, const char *, int);
  48 static void free_path (struct cpp_dir *, int);
  49 static void merge_include_chains (cpp_reader *, int);
  50 static struct cpp_dir *remove_duplicates (cpp_reader *, struct cpp_dir *,
  51                                            struct cpp_dir *,
  52                                            struct cpp_dir *, int);
  53
  54 /* Include chains heads and tails.  */
  55 static struct cpp_dir *heads[4];
  56 static struct cpp_dir *tails[4];
  57 static bool quote_ignores_source_dir;
  58 enum { REASON_QUIET = 0, REASON_NOENT, REASON_DUP, REASON_DUP_SYS };
  59
  60 /* Free an element of the include chain, possibly giving a reason.  */
  61 static void
  62 free_path (struct cpp_dir *path, int reason)
  63 {
  64   switch (reason)
  65     {
  66     case REASON_DUP:
  67     case REASON_DUP_SYS:
  68       fprintf (stderr, _("ignoring duplicate directory \"%s\"\n"), path->name);
  69       if (reason == REASON_DUP_SYS)
  70         fprintf (stderr,
  71  _("  as it is a non-system directory that duplicates a system directory\n"));
  72       break;
  73
  74     case REASON_NOENT:
  75       fprintf (stderr, _("ignoring nonexistent directory \"%s\"\n"),
  76                path->name);
  77       break;
  78
  79     case REASON_QUIET:
  80     default:
  81       break;
  82     }
  83
  84   free (path->name);
  85   free (path);
  86 }
  87
  88 /* Read ENV_VAR for a PATH_SEPARATOR-separated list of file names; and
  89    append all the names to the search path CHAIN.  */
  90 static void
  91 add_env_var_paths (const char *env_var, int chain)
  92 {
  93   char *p, *q, *path;
  94
  95   GET_ENVIRONMENT (q, env_var);
  96
  97   if (!q)
  98     return;
  99
 100   for (p = q; *q; p = q + 1)
 101     {
 102       q = p;
 103       while (*q != 0 && *q != PATH_SEPARATOR)
 104         q++;
 105
 106       if (p == q)
 107         path = xstrdup (".");
 108       else
 109         {
 110           path = xmalloc (q - p + 1);
 111           memcpy (path, p, q - p);
 112           path[q - p] = '\0';
 113         }
 114
 115       add_path (path, chain, chain == SYSTEM);
 116     }
 117 }
 118
 119 /* Append the standard include chain defined in cppdefault.c.  */
 120 static void
 121 add_standard_paths (const char *sysroot, const char *iprefix, int cxx_stdinc)
 122 {
 123   const struct default_include *p;
 124   size_t len;
 125
 126   if (iprefix && (len = cpp_GCC_INCLUDE_DIR_len) != 0)
 127     {
 128       /* Look for directories that start with the standard prefix.
 129          "Translate" them, ie. replace /usr/local/lib/gcc... with
 130          IPREFIX and search them first.  */
 131       for (p = cpp_include_defaults; p->fname; p++)
 132         {
 133           if (!p->cplusplus || cxx_stdinc)
 134             {
 135               /* Should we be translating sysrooted dirs too?  Assume
 136                  that iprefix and sysroot are mutually exclusive, for
 137                  now.  */
 138               if (sysroot && p->add_sysroot)
 139                 continue;
 140               if (!strncmp (p->fname, cpp_GCC_INCLUDE_DIR, len))
 141                 {
 142                   char *str = concat (iprefix, p->fname + len, NULL);
 143                   add_path (str, SYSTEM, p->cxx_aware);
 144                 }
 145             }
 146         }
 147     }
 148
 149   for (p = cpp_include_defaults; p->fname; p++)
 150     {
 151       if (!p->cplusplus || cxx_stdinc)
 152         {
 153           char *str;
 154
 155           /* Should this directory start with the sysroot?  */
 156           if (sysroot && p->add_sysroot)
 157             str = concat (sysroot, p->fname, NULL);
 158           else
 159             str = update_path (p->fname, p->component);
 160
 161           add_path (str, SYSTEM, p->cxx_aware);
 162         }
 163     }
 164 }
 165
 166 /* For each duplicate path in chain HEAD, keep just the first one.
 167    Remove each path in chain HEAD that also exists in chain SYSTEM.
 168    Set the NEXT pointer of the last path in the resulting chain to
 169    JOIN, unless it duplicates JOIN in which case the last path is
 170    removed.  Return the head of the resulting chain.  Any of HEAD,
 171    JOIN and SYSTEM can be NULL.  */
 172 static struct cpp_dir *
 173 remove_duplicates (cpp_reader *pfile, struct cpp_dir *head,
 174                    struct cpp_dir *system, struct cpp_dir *join,
 175                    int verbose)
 176 {
 177   struct cpp_dir **pcur, *tmp, *cur;
 178   struct stat st;
 179
 180   for (pcur = &head; *pcur; )
 181     {
 182       int reason = REASON_QUIET;
 183
 184       cur = *pcur;
 185
 186       if (stat (cur->name, &st))
 187         {
 188           /* Dirs that don't exist are silently ignored, unless verbose.  */
 189           if (errno != ENOENT)
 190             cpp_errno (pfile, CPP_DL_ERROR, cur->name);
 191           else
 192             reason = REASON_NOENT;
 193         }
 194       else if (!S_ISDIR (st.st_mode))
 195         cpp_error_with_line (pfile, CPP_DL_ERROR, 0, 0,
 196                              "%s: not a directory", cur->name);
 197       else
 198         {
 199           INO_T_COPY (cur->ino, st.st_ino);
 200           cur->dev  = st.st_dev;
 201
 202           /* Remove this one if it is in the system chain.  */
 203           reason = REASON_DUP_SYS;
 204           for (tmp = system; tmp; tmp = tmp->next)
 205             if (INO_T_EQ (tmp->ino, cur->ino) && tmp->dev == cur->dev)
 206               break;
 207
 208           if (!tmp)
 209             {
 210               /* Duplicate of something earlier in the same chain?  */
 211               reason = REASON_DUP;
 212               for (tmp = head; tmp != cur; tmp = tmp->next)
 213                 if (INO_T_EQ (cur->ino, tmp->ino) && cur->dev == tmp->dev)
 214                   break;
 215
 216               if (tmp == cur
 217                   /* Last in the chain and duplicate of JOIN?  */
 218                   && !(cur->next == NULL && join
 219                        && INO_T_EQ (cur->ino, join->ino)
 220                        && cur->dev == join->dev))
 221                 {
 222                   /* Unique, so keep this directory.  */
 223                   pcur = &cur->next;
 224                   continue;
 225                 }
 226             }
 227         }
 228
 229       /* Remove this entry from the chain.  */
 230       *pcur = cur->next;
 231       free_path (cur, verbose ? reason: REASON_QUIET);
 232     }
 233
 234   *pcur = join;
 235   return head;
 236 }
 237
 238 /* Merge the four include chains together in the order quote, bracket,
 239    system, after.  Remove duplicate dirs (as determined by
 240    INO_T_EQ()).
 241
 242    We can't just merge the lists and then uniquify them because then
 243    we may lose directories from the <> search path that should be
 244    there; consider -Ifoo -Ibar -I- -Ifoo -Iquux.  It is however safe
 245    to treat -Ibar -Ifoo -I- -Ifoo -Iquux as if written -Ibar -I- -Ifoo
 246    -Iquux.  */
 247 static void
 248 merge_include_chains (cpp_reader *pfile, int verbose)
 249 {
 250   /* Join the SYSTEM and AFTER chains.  Remove duplicates in the
 251      resulting SYSTEM chain.  */
 252   if (heads[SYSTEM])
 253     tails[SYSTEM]->next = heads[AFTER];
 254   else
 255     heads[SYSTEM] = heads[AFTER];
 256   heads[SYSTEM] = remove_duplicates (pfile, heads[SYSTEM], 0, 0, verbose);
 257
 258   /* Remove duplicates from BRACKET that are in itself or SYSTEM, and
 259      join it to SYSTEM.  */
 260   heads[BRACKET] = remove_duplicates (pfile, heads[BRACKET], heads[SYSTEM],
 261                                       heads[SYSTEM], verbose);
 262
 263   /* Remove duplicates from QUOTE that are in itself or SYSTEM, and
 264      join it to BRACKET.  */
 265   heads[QUOTE] = remove_duplicates (pfile, heads[QUOTE], heads[SYSTEM],
 266                                     heads[BRACKET], verbose);
 267
 268   /* If verbose, print the list of dirs to search.  */
 269   if (verbose)
 270     {
 271       struct cpp_dir *p;
 272
 273       fprintf (stderr, _("#include \"...\" search starts here:\n"));
 274       for (p = heads[QUOTE];; p = p->next)
 275         {
 276           if (p == heads[BRACKET])
 277             fprintf (stderr, _("#include <...> search starts here:\n"));
 278           if (!p)
 279             break;
 280           fprintf (stderr, " %s\n", p->name);
 281         }
 282       fprintf (stderr, _("End of search list.\n"));
 283     }
 284 }
 285
 286 /* Use given -I paths for #include "..." but not #include <...>, and
 287    don't search the directory of the present file for #include "...".
 288    (Note that -I. -I- is not the same as the default setup; -I. uses
 289    the compiler's working dir.)  */
 290 void
 291 split_quote_chain (void)
 292 {
 293   heads[QUOTE] = heads[BRACKET];
 294   tails[QUOTE] = tails[BRACKET];
 295   heads[BRACKET] = NULL;
 296   tails[BRACKET] = NULL;
 297   /* This is NOT redundant.  */
 298   quote_ignores_source_dir = true;
 299 }
 300
 301 /* Add PATH to the include chain CHAIN. PATH must be malloc-ed and
 302    NUL-terminated.  */
 303 void
 304 add_path (char *path, int chain, int cxx_aware)
 305 {
 306   struct cpp_dir *p;
 307
 308   p = xmalloc (sizeof (struct cpp_dir));
 309   p->next = NULL;
 310   p->name = path;
 311   if (chain == SYSTEM || chain == AFTER)
 312     p->sysp = 1 + !cxx_aware;
 313   else
 314     p->sysp = 0;
 315
 316   if (tails[chain])
 317     tails[chain]->next = p;
 318   else
 319     heads[chain] = p;
 320   tails[chain] = p;
 321 }
 322
 323 /* Exported function to handle include chain merging, duplicate
 324    removal, and registration with cpplib.  */
 325 void
 326 register_include_chains (cpp_reader *pfile, const char *sysroot,
 327                          const char *iprefix, int stdinc, int cxx_stdinc,
 328                          int verbose)
 329 {
 330   static const char *const lang_env_vars[] =
 331     { "C_INCLUDE_PATH", "CPLUS_INCLUDE_PATH",
 332       "OBJC_INCLUDE_PATH", "OBJCPLUS_INCLUDE_PATH" };
 333   cpp_options *cpp_opts = cpp_get_options (pfile);
 334   size_t idx = (cpp_opts->objc ? 2: 0);
 335
 336   if (cpp_opts->cplusplus)
 337     idx++;
 338   else
 339     cxx_stdinc = false;
 340
 341   /* CPATH and language-dependent environment variables may add to the
 342      include chain.  */
 343   add_env_var_paths ("CPATH", BRACKET);
 344   add_env_var_paths (lang_env_vars[idx], SYSTEM);
 345
 346   /* Finally chain on the standard directories.  */
 347   if (stdinc)
 348     add_standard_paths (sysroot, iprefix, cxx_stdinc);
 349
 350   merge_include_chains (pfile, verbose);
 351
 352   cpp_set_include_chains (pfile, heads[QUOTE], heads[BRACKET],
 353                           quote_ignores_source_dir);
 354 }