/*
* Copyright (c) 1997 Shigio Yamaguchi. All rights reserved.
* Copyright (c) 1999 Tama Communications Corporation. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include "pathconv.h" /* prototypes */
/*
* rel2abs: convert an relative path name into absolute.
*
* i) path relative path
* i) base base directory (must be absolute path)
* o) result result buffer
* i) size size of result buffer
* r) != NULL: absolute path
* == NULL: error
*/
char *
rel2abs(const char *path, const char *base, char *result, const size_t size)
{
const char *pp, *bp;
/*
* endp points the last position which is safe in the result buffer.
*/
const char *endp = result + size - 1;
char *rp;
size_t length;
if (*path == '/') {
if (strlen(path) >= size)
goto erange;
strcpy(result, path);
goto finish;
} else if (*base != '/' || !size) {
errno = EINVAL;
return (NULL);
} else if (size == 1)
goto erange;
length = strlen(base);
if (!strcmp(path, ".") || !strcmp(path, "./")) {
if (length >= size)
goto erange;
strcpy(result, base);
/*
* rp points the last char.
*/
rp = result + length - 1;
/*
* remove the last '/'.
*/
if (*rp == '/') {
if (length > 1)
*rp = 0;
} else
rp++;
/* rp point NULL char */
if (*++path == '/') {
/*
* Append '/' to the tail of path name.
*/
*rp++ = '/';
if (rp > endp)
goto erange;
*rp = 0;
}
goto finish;
}
bp = base + length;
if (*(bp - 1) == '/')
--bp;
/*
* up to root.
*/
for (pp = path; *pp && *pp == '.'; ) {
if (!strncmp(pp, "../", 3)) {
pp += 3;
while (bp > base && *--bp != '/')
;
} else if (!strncmp(pp, "./", 2)) {
pp += 2;
} else if (!strncmp(pp, "..\0", 3)) {
pp += 2;
while (bp > base && *--bp != '/')
;
} else
break;
}
/*
* down to leaf.
*/
length = bp - base;
if (length >= size)
goto erange;
strncpy(result, base, length);
rp = result + length;
if (*pp || *(pp - 1) == '/' || length == 0)
*rp++ = '/';
if (rp + strlen(pp) > endp)
goto erange;
strcpy(rp, pp);
finish:
return result;
erange:
errno = ERANGE;
return (NULL);
}
