On Tue, 16 Jan 2018 09:47:42 +0200
"Vladislav Valtchev (VMware)" <vladislav.valtc...@gmail.com> wrote:
> + errno = 0;
> +
> + /* Read an integer from buf ignoring any non-digit trailing characters.
> */
> + num = strtol(buf, NULL, 10);
> +
> + /* strtol() returned 0: we have to check for errors */
> + if (!num && (errno == EINVAL || errno == ERANGE))
> + return -1;
Repeating again here. According to the man page of strtol():
RETURN VALUE
The strtol() function returns the result of the conversion, unless the
value would underflow or overflow. If an underflow occurs, strtol()
returns LONG_MIN. If an overflow occurs, strtol() returns LONG_MAX.
In both cases, errno is set to ERANGE. Precisely the same holds for
strtoll() (with LLONG_MIN and LLONG_MAX instead of LONG_MIN and
LONG_MAX).
and this:
The implementation may also set errno to EINVAL in case no conversion
was performed (no digits seen, and 0 returned).
Thus, !num is not enough. The example in the man page has:
errno = 0; /* To distinguish success/failure after call */
val = strtol(str, &endptr, base);
/* Check for various possible errors */
if ((errno == ERANGE && (val == LONG_MAX || val == LONG_MIN))
|| (errno != 0 && val == 0)) {
perror("strtol");
exit(EXIT_FAILURE);
}
Let's follow this.
-- Steve
