sbase/pathchk.c
2016-02-11 10:09:38 +00:00

115 lines
2.5 KiB
C

/* See LICENSE file for copyright and license details. */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <limits.h>
#include <stdint.h>
#include <errno.h>
#include <sys/stat.h>
#include "util.h"
#define PORTABLE_CHARACTER_SET "0123456789._-qwertyuiopasdfghjklzxcvbnmQWERTYUIOPASDFGHJKLZXCVBNM"
/* If your system supports more other characters, but not all non-NUL characters, define SYSTEM_CHARACTER_SET. */
static int most = 0;
static int extra = 0;
static int
pathchk(char *filename)
{
char *invalid, *invalid_end, *p, *q;
const char *character_set;
size_t len, maxlen;
struct stat st;
/* Empty? */
if (extra && !*filename) {
weprintf("%s: empty filename\n", argv0);
return 1;
}
/* Leading hyphen? */
if (extra && ((*filename == '-') || strstr(filename, "/-"))) {
weprintf("%s: %s: leading '-' in component of filename\n", argv0, filename);
return 1;
}
/* Nonportable character? */
#ifdef SYSTEM_CHARACTER_SET
character_set = "/"SYSTEM_CHARACTER_SET;
#else
character_set = 0;
#endif
if (most)
character_set = "/"PORTABLE_CHARACTER_SET;
if (character_set && *(invalid = filename + strspn(filename, character_set))) {
for (invalid_end = invalid + 1; *invalid_end & 0x80; invalid_end++);
weprintf("%s: %s: ", argv0, filename);
*invalid_end = 0;
weprintf("nonportable character '%s'\n", invalid);
return 1;
}
/* Symlink error? Non-searchable directory? */
if (lstat(filename, &st) && errno != ENOENT) {
/* lstat rather than stat, so that if filename is a bad symlink, but
* all parents are OK, no error will be detected. */
weprintf("%s: %s:", argv0, filename);
return 1;
}
/* Too long pathname? */
maxlen = most ? _POSIX_PATH_MAX : PATH_MAX;
if (strlen(filename) >= maxlen) {
weprintf("%s: %s: is longer than %zu bytes\n",
argv0, filename, maxlen);
return 1;
}
/* Too long component? */
maxlen = most ? _POSIX_NAME_MAX : NAME_MAX;
for (p = filename; p; p = q) {
q = strchr(p, '/');
len = q ? (size_t)(q++ - p) : strlen(p);
if (len > maxlen) {
weprintf("%s: %s: includes component longer than %zu bytes\n",
argv0, filename, maxlen);
return 1;
}
}
return 0;
}
static void
usage(void)
{
eprintf("usage: %s [-pP] filename...\n", argv0);
}
int
main(int argc, char *argv[])
{
int ret = 0;
ARGBEGIN {
case 'p':
most = 1;
break;
case 'P':
extra = 1;
break;
default:
usage();
} ARGEND;
if (!argc)
usage();
for (; argc--; argv++)
ret |= pathchk(*argv);
return ret;
}