strutil: handle empty fractional in parse rational

[libsigrok.git] / src / strutil.c

diff --git a/src/strutil.c b/src/strutil.c
index 5f48e87bebc02cd2f0eaca8c516aba7b6349e5a1..28f202c9801547e2716d332cf56f7f67c75396c2 100644 (file)
--- a/src/strutil.c
+++ b/src/strutil.c
@@ -621,20 +621,31 @@ SR_API int sr_parse_rational(const char *str, struct sr_rational *ret)
 
        if (str == endptr && (str[0] == '-' || str[0] == '+') && str[1] == '.')
                endptr += 1;
+       else if (str == endptr && str[0] == '.')
+               /* EMPTY */;
        else if (errno)
                return SR_ERR;
 
        if (integral < 0 || str[0] == '-')
                is_negative = true;
 
+       errno = 0;
        if (*endptr == '.') {
-               const char* start = endptr + 1;
+               bool is_exp, is_eos;
+               const char *start = endptr + 1;
                fractional = g_ascii_strtoll(start, &endptr, 10);
+               is_exp = *endptr == 'E' || *endptr == 'e';
+               is_eos = *endptr == '\0';
+               if (endptr == start && (is_exp || is_eos)) {
+                       fractional = 0;
+                       errno = 0;
+               }
                if (errno)
                        return SR_ERR;
                fractional_len = endptr - start;
        }
 
+       errno = 0;
        if ((*endptr == 'E') || (*endptr == 'e')) {
                exponent = g_ascii_strtoll(endptr + 1, &endptr, 10);
                if (errno)