gcc/file-find.c

   1 /* Utility functions for finding files relative to GCC binaries.
   2    Copyright (C) 1992-2020 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 "filenames.h"
  23 #include "file-find.h"
  24
  25 static bool debug = false;
  26
  27 void
  28 find_file_set_debug (bool debug_state)
  29 {
  30   debug = debug_state;
  31 }
  32
  33 char *
  34 find_a_file (struct path_prefix *pprefix, const char *name, int mode)
  35 {
  36   char *temp;
  37   struct prefix_list *pl;
  38   int len = pprefix->max_len + strlen (name) + 1;
  39
  40   if (debug)
  41     fprintf (stderr, "Looking for '%s'\n", name);
  42
  43 #ifdef HOST_EXECUTABLE_SUFFIX
  44   len += strlen (HOST_EXECUTABLE_SUFFIX);
  45 #endif
  46
  47   temp = XNEWVEC (char, len);
  48
  49   /* Determine the filename to execute (special case for absolute paths).  */
  50
  51   if (IS_ABSOLUTE_PATH (name))
  52     {
  53       if (access (name, mode) == 0)
  54         {
  55           strcpy (temp, name);
  56
  57           if (debug)
  58             fprintf (stderr, "  - found: absolute path\n");
  59
  60           return temp;
  61         }
  62
  63 #ifdef HOST_EXECUTABLE_SUFFIX
  64         /* Some systems have a suffix for executable files.
  65            So try appending that.  */
  66       strcpy (temp, name);
  67         strcat (temp, HOST_EXECUTABLE_SUFFIX);
  68
  69         if (access (temp, mode) == 0)
  70           return temp;
  71 #endif
  72
  73       if (debug)
  74         fprintf (stderr, "  - failed to locate using absolute path\n");
  75     }
  76   else
  77     for (pl = pprefix->plist; pl; pl = pl->next)
  78       {
  79         struct stat st;
  80
  81         strcpy (temp, pl->prefix);
  82         strcat (temp, name);
  83
  84         if (stat (temp, &st) >= 0
  85             && ! S_ISDIR (st.st_mode)
  86             && access (temp, mode) == 0)
  87           return temp;
  88
  89 #ifdef HOST_EXECUTABLE_SUFFIX
  90         /* Some systems have a suffix for executable files.
  91            So try appending that.  */
  92         strcat (temp, HOST_EXECUTABLE_SUFFIX);
  93
  94         if (stat (temp, &st) >= 0
  95             && ! S_ISDIR (st.st_mode)
  96             && access (temp, mode) == 0)
  97           return temp;
  98 #endif
  99       }
 100
 101   if (debug && pprefix->plist == NULL)
 102     fprintf (stderr, "  - failed: no entries in prefix list\n");
 103
 104   free (temp);
 105   return 0;
 106 }
 107
 108 /* Add an entry for PREFIX to prefix list PREFIX.
 109    Add at beginning if FIRST is true.  */
 110
 111 void
 112 do_add_prefix (struct path_prefix *pprefix, const char *prefix, bool first)
 113 {
 114   struct prefix_list *pl, **prev;
 115   int len;
 116
 117   if (pprefix->plist && !first)
 118     {
 119       for (pl = pprefix->plist; pl->next; pl = pl->next)
 120         ;
 121       prev = &pl->next;
 122     }
 123   else
 124     prev = &pprefix->plist;
 125
 126   /* Keep track of the longest prefix.  */
 127
 128   len = strlen (prefix);
 129   if (len > pprefix->max_len)
 130     pprefix->max_len = len;
 131
 132   pl = XNEW (struct prefix_list);
 133   pl->prefix = xstrdup (prefix);
 134
 135   if (*prev)
 136     pl->next = *prev;
 137   else
 138     pl->next = (struct prefix_list *) 0;
 139   *prev = pl;
 140 }
 141
 142 /* Add an entry for PREFIX at the end of prefix list PREFIX.  */
 143
 144 void
 145 add_prefix (struct path_prefix *pprefix, const char *prefix)
 146 {
 147   do_add_prefix (pprefix, prefix, false);
 148 }
 149
 150 /* Add an entry for PREFIX at the begin of prefix list PREFIX.  */
 151
 152 void
 153 add_prefix_begin (struct path_prefix *pprefix, const char *prefix)
 154 {
 155   do_add_prefix (pprefix, prefix, true);
 156 }
 157
 158 /* Take the value of the environment variable ENV, break it into a path, and
 159    add of the entries to PPREFIX.  */
 160
 161 void
 162 prefix_from_env (const char *env, struct path_prefix *pprefix)
 163 {
 164   const char *p;
 165   p = getenv (env);
 166
 167   if (p)
 168     prefix_from_string (p, pprefix);
 169 }
 170
 171 void
 172 prefix_from_string (const char *p, struct path_prefix *pprefix)
 173 {
 174   const char *startp, *endp;
 175   char *nstore = XNEWVEC (char, strlen (p) + 3);
 176
 177   if (debug)
 178     fprintf (stderr, "Convert string '%s' into prefixes, separator = '%c'\n", p, PATH_SEPARATOR);
 179
 180   startp = endp = p;
 181   while (1)
 182     {
 183       if (*endp == PATH_SEPARATOR || *endp == 0)
 184         {
 185           strncpy (nstore, startp, endp-startp);
 186           if (endp == startp)
 187             {
 188               strcpy (nstore, "./");
 189             }
 190           else if (! IS_DIR_SEPARATOR (endp[-1]))
 191             {
 192               nstore[endp-startp] = DIR_SEPARATOR;
 193               nstore[endp-startp+1] = 0;
 194             }
 195           else
 196             nstore[endp-startp] = 0;
 197
 198           if (debug)
 199             fprintf (stderr, "  - add prefix: %s\n", nstore);
 200
 201           add_prefix (pprefix, nstore);
 202           if (*endp == 0)
 203             break;
 204           endp = startp = endp + 1;
 205         }
 206       else
 207         endp++;
 208     }
 209   free (nstore);
 210 }