Mercurial > hg-old > index.cgi

comparison lib/basename.c @ 265:68fbca173508 2.6

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
Added generated files for release
author lost
date Tue, 22 Dec 2009 05:31:23 +0000
parents
children
comparison
equal deleted inserted replaced
264:61d1db1dfe2a 265:68fbca173508
1 /* basename.c -- return the last element in a file name
2
3 Copyright (C) 1990, 1998, 1999, 2000, 2001, 2003, 2004, 2005, 2006 Free
4 Software Foundation, Inc.
5
6 This program is free software: you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
10
11 This program 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
14 GNU General Public License for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>. */
18
19 #include <config.h>
20
21 #include "dirname.h"
22
23 #include <string.h>
24 #include "xalloc.h"
25 #include "xstrndup.h"
26
27 /* Return the address of the last file name component of NAME. If
28 NAME has no relative file name components because it is a file
29 system root, return the empty string. */
30
31 char *
32 last_component (char const *name)
33 {
34 char const *base = name + FILE_SYSTEM_PREFIX_LEN (name);
35 char const *p;
36 bool saw_slash = false;
37
38 while (ISSLASH (*base))
39 base++;
40
41 for (p = base; *p; p++)
42 {
43 if (ISSLASH (*p))
44 saw_slash = true;
45 else if (saw_slash)
46 {
47 base = p;
48 saw_slash = false;
49 }
50 }
51
52 return (char *) base;
53 }
54
55
56 /* In general, we can't use the builtin `basename' function if available,
57 since it has different meanings in different environments.
58 In some environments the builtin `basename' modifies its argument.
59
60 Return the last file name component of NAME, allocated with
61 xmalloc. On systems with drive letters, a leading "./"
62 distinguishes relative names that would otherwise look like a drive
63 letter. Unlike POSIX basename(), NAME cannot be NULL,
64 base_name("") returns "", and the first trailing slash is not
65 stripped.
66
67 If lstat (NAME) would succeed, then { chdir (dir_name (NAME));
68 lstat (base_name (NAME)); } will access the same file. Likewise,
69 if the sequence { chdir (dir_name (NAME));
70 rename (base_name (NAME), "foo"); } succeeds, you have renamed NAME
71 to "foo" in the same directory NAME was in. */
72
73 char *
74 base_name (char const *name)
75 {
76 char const *base = last_component (name);
77 size_t length;
78
79 /* If there is no last component, then name is a file system root or the
80 empty string. */
81 if (! *base)
82 return xstrndup (name, base_len (name));
83
84 /* Collapse a sequence of trailing slashes into one. */
85 length = base_len (base);
86 if (ISSLASH (base[length]))
87 length++;
88
89 /* On systems with drive letters, `a/b:c' must return `./b:c' rather
90 than `b:c' to avoid confusion with a drive letter. On systems
91 with pure POSIX semantics, this is not an issue. */
92 if (FILE_SYSTEM_PREFIX_LEN (base))
93 {
94 char *p = xmalloc (length + 3);
95 p[0] = '.';
96 p[1] = '/';
97 memcpy (p + 2, base, length);
98 p[length + 2] = '\0';
99 return p;
100 }
101
102 /* Finally, copy the basename. */
103 return xstrndup (base, length);
104 }
105
106 /* Return the length of the basename NAME. Typically NAME is the
107 value returned by base_name or last_component. Act like strlen
108 (NAME), except omit all trailing slashes. */
109
110 size_t
111 base_len (char const *name)
112 {
113 size_t len;
114 size_t prefix_len = FILE_SYSTEM_PREFIX_LEN (name);
115
116 for (len = strlen (name); 1 < len && ISSLASH (name[len - 1]); len--)
117 continue;
118
119 if (DOUBLE_SLASH_IS_DISTINCT_ROOT && len == 1
120 && ISSLASH (name[0]) && ISSLASH (name[1]) && ! name[2])
121 return 2;
122
123 if (FILE_SYSTEM_DRIVE_PREFIX_CAN_BE_RELATIVE && prefix_len
124 && len == prefix_len && ISSLASH (name[prefix_len]))
125 return prefix_len + 1;
126
127 return len;
128 }