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

   1 /* addext.c -- add an extension to a file name
   2    Copyright (C) 1990, 1997-1999, 2001-2003 Free Software Foundation, Inc.
   3
   4    This program is free software; you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation; either version 2, or (at your option)
   7    any later version.
   8
   9    This program 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
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program; see the file COPYING.
  16    If not, write to the Free Software Foundation,
  17    59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  18
  19 /* Written by David MacKenzie <djm@gnu.ai.mit.edu> and Paul Eggert */
  20
  21 #if HAVE_CONFIG_H
  22 # include <config.h>
  23 #endif
  24
  25 #ifndef HAVE_DOS_FILE_NAMES
  26 # define HAVE_DOS_FILE_NAMES 0
  27 #endif
  28 #ifndef HAVE_LONG_FILE_NAMES
  29 # define HAVE_LONG_FILE_NAMES 0
  30 #endif
  31
  32 #include "backupfile.h"
  33
  34 #include <limits.h>
  35 #ifndef _POSIX_NAME_MAX
  36 # define _POSIX_NAME_MAX 14
  37 #endif
  38
  39 #include <sys/types.h>
  40 #if HAVE_STRING_H
  41 # include <string.h>
  42 #else
  43 # include <strings.h>
  44 #endif
  45
  46 #if HAVE_UNISTD_H
  47 # include <unistd.h>
  48 #endif
  49
  50 #include "basename.h"
  51
  52 /* Append to FILENAME the extension EXT, unless the result would be too long,
  53    in which case just append the character E.  */
  54
  55 void
  56 addext (char *filename, char const *ext, char e)
  57 {
  58   char *s = basename (filename);
  59   size_t slen = strlen (s), extlen = strlen (ext);
  60   long slen_max = -1;
  61
  62 #if HAVE_PATHCONF && defined _PC_NAME_MAX
  63   if (slen + extlen <= _POSIX_NAME_MAX && ! HAVE_DOS_FILE_NAMES)
  64     /* The file name is so short there's no need to call pathconf.  */
  65     slen_max = _POSIX_NAME_MAX;
  66   else if (s == filename)
  67     slen_max = pathconf (".", _PC_NAME_MAX);
  68   else
  69     {
  70       char c = *s;
  71       *s = 0;
  72       slen_max = pathconf (filename, _PC_NAME_MAX);
  73       *s = c;
  74     }
  75 #endif
  76   if (slen_max < 0)
  77     slen_max = HAVE_LONG_FILE_NAMES ? 255 : 14;
  78
  79   if (HAVE_DOS_FILE_NAMES && slen_max <= 12)
  80     {
  81       /* Live within DOS's 8.3 limit.  */
  82       char *dot = strchr (s, '.');
  83       if (dot)
  84         {
  85           slen -= dot + 1 - s;
  86           s = dot + 1;
  87           slen_max = 3;
  88         }
  89       else
  90         slen_max = 8;
  91       extlen = 9; /* Don't use EXT.  */
  92     }
  93
  94   if (slen + extlen <= slen_max)
  95     strcpy (s + slen, ext);
  96   else
  97     {
  98       if (slen_max <= slen)
  99         slen = slen_max - 1;
 100       s[slen] = e;
 101       s[slen + 1] = 0;
 102     }
 103 }