xref: /netbsd-src/external/gpl2/gettext/dist/gettext-tools/gnulib-lib/addext.c (revision 946379e7b37692fc43f68eb0d1c10daa0a7f3b6c)
1 /* addext.c -- add an extension to a file name
2    Copyright (C) 1990, 1997-1999, 2001-2003, 2005-2006 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    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
18 
19 /* Written by David MacKenzie <djm@gnu.ai.mit.edu> and Paul Eggert */
20 
21 #include <config.h>
22 
23 #ifndef HAVE_DOS_FILE_NAMES
24 # define HAVE_DOS_FILE_NAMES 0
25 #endif
26 #ifndef HAVE_LONG_FILE_NAMES
27 # define HAVE_LONG_FILE_NAMES 0
28 #endif
29 
30 #include "backupfile.h"
31 
32 #include <limits.h>
33 #ifndef _POSIX_NAME_MAX
34 # define _POSIX_NAME_MAX 14
35 #endif
36 
37 #include <sys/types.h>
38 #if HAVE_STRING_H
39 # include <string.h>
40 #else
41 # include <strings.h>
42 #endif
43 
44 #include <unistd.h>
45 
46 #include "basename.h"
47 
48 /* Append to FILENAME the extension EXT, unless the result would be too long,
49    in which case just append the character E.  */
50 
51 void
addext(char * filename,char const * ext,char e)52 addext (char *filename, char const *ext, char e)
53 {
54   char *s = basename (filename);
55   size_t slen = strlen (s), extlen = strlen (ext);
56   long slen_max = -1;
57 
58 #if HAVE_PATHCONF && defined _PC_NAME_MAX
59   if (slen + extlen <= _POSIX_NAME_MAX && ! HAVE_DOS_FILE_NAMES)
60     /* The file name is so short there's no need to call pathconf.  */
61     slen_max = _POSIX_NAME_MAX;
62   else if (s == filename)
63     slen_max = pathconf (".", _PC_NAME_MAX);
64   else
65     {
66       char c = *s;
67       *s = 0;
68       slen_max = pathconf (filename, _PC_NAME_MAX);
69       *s = c;
70     }
71 #endif
72   if (slen_max < 0)
73     slen_max = HAVE_LONG_FILE_NAMES ? 255 : 14;
74 
75   if (HAVE_DOS_FILE_NAMES && slen_max <= 12)
76     {
77       /* Live within DOS's 8.3 limit.  */
78       char *dot = strchr (s, '.');
79       if (dot)
80 	{
81 	  slen -= dot + 1 - s;
82 	  s = dot + 1;
83 	  slen_max = 3;
84 	}
85       else
86 	slen_max = 8;
87       extlen = 9; /* Don't use EXT.  */
88     }
89 
90   if (slen + extlen <= slen_max)
91     strcpy (s + slen, ext);
92   else
93     {
94       if (slen_max <= slen)
95 	slen = slen_max - 1;
96       s[slen] = e;
97       s[slen + 1] = 0;
98     }
99 }
100