mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-09 23:00:07 +00:00
80 lines
2.3 KiB
C
80 lines
2.3 KiB
C
/* dirname - return directory part of PATH.
|
|
Copyright (C) 1996-2024 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
|
|
The GNU C Library is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU Lesser General Public
|
|
License as published by the Free Software Foundation; either
|
|
version 2.1 of the License, or (at your option) any later version.
|
|
|
|
The GNU C Library is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public
|
|
License along with the GNU C Library; if not, see
|
|
<https://www.gnu.org/licenses/>. */
|
|
|
|
#include <libgen.h>
|
|
#include <string.h>
|
|
|
|
|
|
char *
|
|
dirname (char *path)
|
|
{
|
|
static const char dot[] = ".";
|
|
char *last_slash;
|
|
|
|
/* Find last '/'. */
|
|
last_slash = path != NULL ? strrchr (path, '/') : NULL;
|
|
|
|
if (last_slash != NULL && last_slash != path && last_slash[1] == '\0')
|
|
{
|
|
/* Determine whether all remaining characters are slashes. */
|
|
char *runp;
|
|
|
|
for (runp = last_slash; runp != path; --runp)
|
|
if (runp[-1] != '/')
|
|
break;
|
|
|
|
/* The '/' is the last character, we have to look further. */
|
|
if (runp != path)
|
|
last_slash = __memrchr (path, '/', runp - path);
|
|
}
|
|
|
|
if (last_slash != NULL)
|
|
{
|
|
/* Determine whether all remaining characters are slashes. */
|
|
char *runp;
|
|
|
|
for (runp = last_slash; runp != path; --runp)
|
|
if (runp[-1] != '/')
|
|
break;
|
|
|
|
/* Terminate the path. */
|
|
if (runp == path)
|
|
{
|
|
/* The last slash is the first character in the string. We have to
|
|
return "/". As a special case we have to return "//" if there
|
|
are exactly two slashes at the beginning of the string. See
|
|
XBD 4.10 Path Name Resolution for more information. */
|
|
if (last_slash == path + 1)
|
|
++last_slash;
|
|
else
|
|
last_slash = path + 1;
|
|
}
|
|
else
|
|
last_slash = runp;
|
|
|
|
last_slash[0] = '\0';
|
|
}
|
|
else
|
|
/* This assignment is ill-designed but the XPG specs require to
|
|
return a string containing "." in any case no directory part is
|
|
found and so a static and constant string is required. */
|
|
path = (char *) dot;
|
|
|
|
return path;
|
|
}
|