From: Gerhard Sittig <redacted>
Date: Thu, 19 Jul 2018 19:05:54 +0000 (+0200)
Subject: strutil: handle empty fractional in parse rational
X-Git-Url: https://sigrok.org/gitaction?a=commitdiff_plain;h=42408643f9dcb80d1744aaa4d08e0170594daad1;p=libsigrok.git

strutil: handle empty fractional in parse rational

Accept numbers like "123." where the period (dot) is present yet the
fractional part is empty. Adding a period but no additional digits is a
popular method of turning an otherwise integer literal into a float.
Compilers and strtod() routines accept this notation, too, so we have to
expect seeing such input.
---

diff --git a/src/strutil.c b/src/strutil.c
index 99e711d9..28f202c9 100644
--- a/src/strutil.c
+++ b/src/strutil.c
@@ -631,8 +631,15 @@ SR_API int sr_parse_rational(const char *str, struct sr_rational *ret)
 
 	errno = 0;
 	if (*endptr == '.') {
+		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;