source/texk/kpathsea/dir.c

   1 /* dir.c: directory operations.
   2
   3    Copyright 1992, 1993, 1994, 1995, 2008-2012 Karl Berry.
   4    Copyright 2000, 2002, 2005 Olaf Weber.
   5
   6    This library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Lesser General Public
   8    License as published by the Free Software Foundation; either
   9    version 2.1 of the License, or (at your option) any later version.
  10
  11    This library is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14    Lesser General Public License for more details.
  15
  16    You should have received a copy of the GNU Lesser General Public License
  17    along with this library; if not, see <http://www.gnu.org/licenses/>.  */
  18
  19 #include <kpathsea/config.h>
  20
  21 #include <kpathsea/c-dir.h>
  22 #include <kpathsea/c-stat.h>
  23 #include <kpathsea/hash.h>
  24 #include <kpathsea/pathsearch.h>
  25
  26 /* Return true if FN is a directory or a symlink to a directory,
  27    false if not. */
  28
  29 boolean
  30 kpathsea_dir_p (kpathsea kpse, string fn)
  31 {
  32   /* FIXME : using the stat() replacement in gnuw32,
  33          we could avoid this win32 specific code. However,
  34          I wonder if it would be as fast as this one is ?
  35   */
  36 #ifdef WIN32
  37   int fa;
  38
  39   kpathsea_normalize_path(kpse, fn);
  40   fa = GetFileAttributes(fn);
  41
  42 #ifdef KPSE_DEBUG
  43   if (KPATHSEA_DEBUG_P (KPSE_DEBUG_STAT)) {
  44     if (fa == 0xFFFFFFFF) {
  45       fprintf(stderr, "failed to get file attributes for %s (%d)\n",
  46               fn, (int)(GetLastError()));
  47     } else {
  48       fprintf(stderr, "path %s %s a directory\n",
  49               fn , (fa & FILE_ATTRIBUTE_DIRECTORY) ?
  50               "is"  : "is not");
  51     }
  52   }
  53 #endif /* KPSE_DEBUG */
  54   return (fa != 0xFFFFFFFF && (fa & FILE_ATTRIBUTE_DIRECTORY));
  55 #else /* !WIN32 */
  56   struct stat stats;
  57   return stat (fn, &stats) == 0 && S_ISDIR (stats.st_mode);
  58 #endif /* !WIN32 */
  59 }
  60
  61 #if defined(KPSE_COMPAT_API)
  62 boolean
  63 dir_p (string fn)
  64 {
  65     return kpathsea_dir_p (kpse_def, fn);
  66 }
  67 #endif
  68
  69
  70 /*
  71   Return -1 if FN isn't a directory, else its number of links.
  72   Duplicate the call to stat; no need to incur overhead of a function
  73   call for that little bit of cleanliness.
  74
  75   The process is a bit different under Win32 : the first call
  76   memoizes the nlinks value, the following ones retrieve it.
  77 */
  78 int
  79 kpathsea_dir_links (kpathsea kpse, const_string fn, long nlinks)
  80 {
  81   const_string *hash_ret;
  82
  83   if (kpse->link_table.size == 0)
  84     kpse->link_table = hash_create (457);
  85
  86 #ifdef KPSE_DEBUG
  87   /* This is annoying, but since we're storing integers as pointers, we
  88      can't print them as strings.  */
  89   if (KPATHSEA_DEBUG_P (KPSE_DEBUG_HASH))
  90     kpse->debug_hash_lookup_int = true;
  91 #endif
  92
  93   hash_ret = hash_lookup (kpse->link_table, fn);
  94
  95 #ifdef KPSE_DEBUG
  96   if (KPATHSEA_DEBUG_P (KPSE_DEBUG_HASH))
  97     kpse->debug_hash_lookup_int = false;
  98 #endif
  99
 100   /* Have to cast the int we need to/from the const_string that the hash
 101      table stores for values. Let's hope an int fits in a pointer.  */
 102   if (hash_ret) {
 103 #ifdef WIN32
 104       memcpy(&nlinks, hash_ret, sizeof(nlinks));
 105 #else
 106       nlinks = (long) *hash_ret;
 107 #endif
 108   } else {
 109 #ifdef WIN32
 110       /* Insert it only if we have some informations about it. */
 111       if (nlinks) {
 112         char str_nlinks[sizeof(nlinks)+1];
 113         memcpy(str_nlinks, (char *)&nlinks, sizeof(nlinks));
 114         str_nlinks[sizeof(nlinks)] = '\0';
 115         /* It's up to us to copy the value.  */
 116         hash_insert(&(kpse->link_table), xstrdup (fn),
 117                     (const_string) str_nlinks);
 118       }
 119 #else
 120       struct stat stats;
 121       if (stat (fn, &stats) == 0 && S_ISDIR (stats.st_mode))
 122         nlinks = stats.st_nlink;
 123       else
 124         nlinks = -1;
 125       /* It's up to us to copy the value.  */
 126       hash_insert(&(kpse->link_table), xstrdup(fn), (const_string)nlinks);
 127 #endif
 128
 129 #ifdef KPSE_DEBUG
 130       if (KPATHSEA_DEBUG_P (KPSE_DEBUG_STAT))
 131         DEBUGF2 ("dir_links(%s) => %ld\n", fn, nlinks);
 132 #endif
 133   }
 134
 135   /* In any case, return nlinks
 136      (either 0, the value inserted or the value retrieved. */
 137   return nlinks;
 138 }
 139
 140 #if defined (KPSE_COMPAT_API)
 141 int
 142 dir_links (const_string fn, long nlinks)
 143 {
 144     return kpathsea_dir_links (kpse_def, fn, nlinks);
 145 }
 146 #endif