gnu/dist/gettext/gettext-tools/lib/tmpdir.c

   1 /* Copyright (C) 1999, 2001-2002 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Library General Public License as
   6    published by the Free Software Foundation; either version 2 of the
   7    License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Library General Public License for more details.
  13
  14    You should have received a copy of the GNU Library General Public
  15    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  16    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17    Boston, MA 02111-1307, USA.  */
  18
  19 /* Extracted from sysdeps/posix/tempname.c.  */
  20
  21 #ifdef HAVE_CONFIG_H
  22 # include "config.h"
  23 #endif
  24
  25 /* Specification.  */
  26 #include "tmpdir.h"
  27
  28 #include <stdbool.h>
  29 #include <stdlib.h>
  30 #include <string.h>
  31
  32 #include <errno.h>
  33 #ifndef __set_errno
  34 # define __set_errno(Val) errno = (Val)
  35 #endif
  36
  37 #include <stdio.h>
  38 #ifndef P_tmpdir
  39 # define P_tmpdir "/tmp"
  40 #endif
  41
  42 #include <sys/stat.h>
  43 #if STAT_MACROS_BROKEN
  44 # undef S_ISDIR
  45 #endif
  46 #if !defined S_ISDIR && defined S_IFDIR
  47 # define S_ISDIR(mode) (((mode) & S_IFMT) == S_IFDIR)
  48 #endif
  49 #if !S_IRUSR && S_IREAD
  50 # define S_IRUSR S_IREAD
  51 #endif
  52 #if !S_IRUSR
  53 # define S_IRUSR 00400
  54 #endif
  55 #if !S_IWUSR && S_IWRITE
  56 # define S_IWUSR S_IWRITE
  57 #endif
  58 #if !S_IWUSR
  59 # define S_IWUSR 00200
  60 #endif
  61 #if !S_IXUSR && S_IEXEC
  62 # define S_IXUSR S_IEXEC
  63 #endif
  64 #if !S_IXUSR
  65 # define S_IXUSR 00100
  66 #endif
  67
  68 #if _LIBC
  69 # define struct_stat64 struct stat64
  70 #else
  71 # define struct_stat64 struct stat
  72 # define __xstat64(version, path, buf) stat (path, buf)
  73 #endif
  74
  75 #if ! (HAVE___SECURE_GETENV || _LIBC)
  76 # define __secure_getenv getenv
  77 #endif
  78
  79
  80 /* Return nonzero if DIR is an existent directory.  */
  81 static bool
  82 direxists (const char *dir)
  83 {
  84   struct_stat64 buf;
  85   return __xstat64 (_STAT_VER, dir, &buf) == 0 && S_ISDIR (buf.st_mode);
  86 }
  87
  88 /* Path search algorithm, for tmpnam, tmpfile, etc.  If DIR is
  89    non-null and exists, uses it; otherwise uses the first of $TMPDIR,
  90    P_tmpdir, /tmp that exists.  Copies into TMPL a template suitable
  91    for use with mk[s]temp.  Will fail (-1) if DIR is non-null and
  92    doesn't exist, none of the searched dirs exists, or there's not
  93    enough space in TMPL. */
  94 int
  95 path_search (char *tmpl, size_t tmpl_len, const char *dir, const char *pfx,
  96              bool try_tmpdir)
  97 {
  98   const char *d;
  99   size_t dlen, plen;
 100
 101   if (!pfx || !pfx[0])
 102     {
 103       pfx = "file";
 104       plen = 4;
 105     }
 106   else
 107     {
 108       plen = strlen (pfx);
 109       if (plen > 5)
 110         plen = 5;
 111     }
 112
 113   if (try_tmpdir)
 114     {
 115       d = __secure_getenv ("TMPDIR");
 116       if (d != NULL && direxists (d))
 117         dir = d;
 118       else if (dir != NULL && direxists (dir))
 119         /* nothing */ ;
 120       else
 121         dir = NULL;
 122     }
 123   if (dir == NULL)
 124     {
 125       if (direxists (P_tmpdir))
 126         dir = P_tmpdir;
 127       else if (strcmp (P_tmpdir, "/tmp") != 0 && direxists ("/tmp"))
 128         dir = "/tmp";
 129       else
 130         {
 131           __set_errno (ENOENT);
 132           return -1;
 133         }
 134     }
 135
 136   dlen = strlen (dir);
 137   while (dlen > 1 && dir[dlen - 1] == '/')
 138     dlen--;                     /* remove trailing slashes */
 139
 140   /* check we have room for "${dir}/${pfx}XXXXXX\0" */
 141   if (tmpl_len < dlen + 1 + plen + 6 + 1)
 142     {
 143       __set_errno (EINVAL);
 144       return -1;
 145     }
 146
 147   sprintf (tmpl, "%.*s/%.*sXXXXXX", (int) dlen, dir, (int) plen, pfx);
 148   return 0;
 149 }