busybox/libbb/simplify_path.c
Denis Vlasenko 6ca0444420 syslogd: fix "readpath bug" by using readlink instead
libbb: rename xgetcwd and xreadlink
2007-02-11 16:19:28 +00:00

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1018 B
C

/* vi: set sw=4 ts=4: */
/*
* bb_simplify_path implementation for busybox
*
* Copyright (C) 2001 Manuel Novoa III <mjn3@codepoet.org>
*
* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
*/
#include "libbb.h"
char *bb_simplify_path(const char *path)
{
char *s, *start, *p;
if (path[0] == '/')
start = xstrdup(path);
else {
s = xrealloc_getcwd_or_warn(NULL);
start = concat_path_file(s, path);
free(s);
}
p = s = start;
do {
if (*p == '/') {
if (*s == '/') { /* skip duplicate (or initial) slash */
continue;
} else if (*s == '.') {
if (s[1] == '/' || s[1] == 0) { /* remove extra '.' */
continue;
} else if ((s[1] == '.') && (s[2] == '/' || s[2] == 0)) {
++s;
if (p > start) {
while (*--p != '/'); /* omit previous dir */
}
continue;
}
}
}
*++p = *s;
} while (*++s);
if ((p == start) || (*p != '/')) { /* not a trailing slash */
++p; /* so keep last character */
}
*p = 0;
return start;
}