Make strtol() parsing even stricter in parseoffset()

Be strict about what we pass to it and how we handle errors.
The base-check is done by strtol anyway.
Also improve error-reporting.
This commit is contained in:
FRIGN 2015-09-30 20:05:14 +02:00 committed by sin
parent c514c580ec
commit 8be7c42863
1 changed files with 11 additions and 14 deletions

View File

@ -1,5 +1,6 @@
/* See LICENSE file for copyright and license details. */
#include <ctype.h>
#include <errno.h>
#include <inttypes.h>
#include <stdlib.h>
#include <string.h>
@ -9,25 +10,21 @@
off_t
parseoffset(const char *str)
{
off_t res;
size_t scale = 1;
int base = 10;
off_t res, scale = 1;
char *end;
if (!str || !*str) {
weprintf("parseoffset: empty string\n");
/* strictly check what strtol() usually would let pass */
if (!str || !*str || isspace(*str) || *str == '+' || *str == '-') {
weprintf("parseoffset %s: invalid value\n", str);
return -1;
}
/* bases */
if (!strncasecmp(str, "0x", strlen("0x"))) {
base = 16;
} else if (*str == '0') {
str++;
base = 8;
errno = 0;
res = strtol(str, &end, 0);
if (errno) {
weprintf("parseoffset %s: invalid value\n", str);
return -1;
}
res = strtol(str, &end, base);
if (res < 0) {
weprintf("parseoffset %s: negative value\n", str);
return -1;
@ -49,7 +46,7 @@ parseoffset(const char *str)
scale = 1024L * 1024L * 1024L;
break;
default:
weprintf("parseoffset %s: invalid suffix\n", str);
weprintf("parseoffset %s: invalid suffix '%s'\n", str, end);
return -1;
}
}