lib: Fix a few bugs in trailing_strtoln()

At present this has a minor bug in that it reads the byte before the
start of the string, if it is empty. Also it doesn't handle a
non-numeric prefix which is only one character long.

Fix these bugs with a reworked implementation. Add a test for the second
case. The first one is hard to test.

Signed-off-by: Simon Glass <sjg@chromium.org>
This commit is contained in:
Simon Glass 2022-04-24 23:30:57 -06:00 committed by Tom Rini
parent 4e64cae0a0
commit d667a0d8f4
3 changed files with 11 additions and 5 deletions

View file

@ -98,6 +98,9 @@ long long simple_strtoll(const char *cp, char **endp, unsigned int base);
* Given a string this finds a trailing number on the string and returns it.
* For example, "abc123" would return 123.
*
* Note that this does not handle a string without a prefix. See dectoul() for
* that case.
*
* @str: String to examine
* Return: trailing number if found, else -1
*/

View file

@ -189,11 +189,12 @@ long trailing_strtoln(const char *str, const char *end)
if (!end)
end = str + strlen(str);
if (isdigit(end[-1])) {
for (p = end - 1; p > str; p--) {
if (!isdigit(*p))
return dectoul(p + 1, NULL);
}
p = end - 1;
if (p > str && isdigit(*p)) {
do {
if (!isdigit(p[-1]))
return dectoul(p, NULL);
} while (--p > str);
}
return -1;

View file

@ -257,6 +257,8 @@ static int str_trailing(struct unit_test_state *uts)
ut_asserteq(123, trailing_strtoln(str1, str1 + 6));
ut_asserteq(-1, trailing_strtoln(str1, str1 + 9));
ut_asserteq(3, trailing_strtol("a3"));
return 0;
}
STR_TEST(str_trailing, 0);