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-rw-r--r--gl/dirname.c64
1 files changed, 9 insertions, 55 deletions
diff --git a/gl/dirname.c b/gl/dirname.c
index c27e5b5..953a9ac 100644
--- a/gl/dirname.c
+++ b/gl/dirname.c
@@ -1,6 +1,6 @@
1/* dirname.c -- return all but the last element in a file name 1/* dirname.c -- return all but the last element in a file name
2 2
3 Copyright (C) 1990, 1998, 2000, 2001, 2003, 2004, 2005, 2006 Free Software 3 Copyright (C) 1990, 1998, 2000-2001, 2003-2006, 2009-2010 Free Software
4 Foundation, Inc. 4 Foundation, Inc.
5 5
6 This program is free software: you can redistribute it and/or modify 6 This program is free software: you can redistribute it and/or modify
@@ -20,65 +20,19 @@
20 20
21#include "dirname.h" 21#include "dirname.h"
22 22
23#include <stdlib.h>
23#include <string.h> 24#include <string.h>
24#include "xalloc.h" 25#include "xalloc.h"
25 26
26/* Return the length of the prefix of FILE that will be used by 27/* Just like mdir_name (dirname-lgpl.c), except, rather than
27 dir_name. If FILE is in the working directory, this returns zero 28 returning NULL upon malloc failure, here, we report the
28 even though `dir_name (FILE)' will return ".". Works properly even 29 "memory exhausted" condition and exit. */
29 if there are trailing slashes (by effectively ignoring them). */
30
31size_t
32dir_len (char const *file)
33{
34 size_t prefix_length = FILE_SYSTEM_PREFIX_LEN (file);
35 size_t length;
36
37 /* Advance prefix_length beyond important leading slashes. */
38 prefix_length += (prefix_length != 0
39 ? (FILE_SYSTEM_DRIVE_PREFIX_CAN_BE_RELATIVE
40 && ISSLASH (file[prefix_length]))
41 : (ISSLASH (file[0])
42 ? ((DOUBLE_SLASH_IS_DISTINCT_ROOT
43 && ISSLASH (file[1]) && ! ISSLASH (file[2])
44 ? 2 : 1))
45 : 0));
46
47 /* Strip the basename and any redundant slashes before it. */
48 for (length = last_component (file) - file;
49 prefix_length < length; length--)
50 if (! ISSLASH (file[length - 1]))
51 break;
52 return length;
53}
54
55
56/* In general, we can't use the builtin `dirname' function if available,
57 since it has different meanings in different environments.
58 In some environments the builtin `dirname' modifies its argument.
59
60 Return the leading directories part of FILE, allocated with xmalloc.
61 Works properly even if there are trailing slashes (by effectively
62 ignoring them). Unlike POSIX dirname(), FILE cannot be NULL.
63
64 If lstat (FILE) would succeed, then { chdir (dir_name (FILE));
65 lstat (base_name (FILE)); } will access the same file. Likewise,
66 if the sequence { chdir (dir_name (FILE));
67 rename (base_name (FILE), "foo"); } succeeds, you have renamed FILE
68 to "foo" in the same directory FILE was in. */
69 30
70char * 31char *
71dir_name (char const *file) 32dir_name (char const *file)
72{ 33{
73 size_t length = dir_len (file); 34 char *result = mdir_name (file);
74 bool append_dot = (length == 0 35 if (!result)
75 || (FILE_SYSTEM_DRIVE_PREFIX_CAN_BE_RELATIVE 36 xalloc_die ();
76 && length == FILE_SYSTEM_PREFIX_LEN (file) 37 return result;
77 && file[2] != '\0' && ! ISSLASH (file[2])));
78 char *dir = xmalloc (length + append_dot + 1);
79 memcpy (dir, file, length);
80 if (append_dot)
81 dir[length++] = '.';
82 dir[length] = '\0';
83 return dir;
84} 38}