sic

commit d9bda20849c464eff0adb56414da1840abc6ef6a
parent df4c0611366bf361fa263fbc57009cbe68456855
Author: Hiltjo Posthuma <hiltjo@codemadness.org>
Date:   Thu,  6 May 2021 01:09:21 +0200

fix undefined behaviour of using isspace ctype function

cast all ctype(3) functions argument to (unsigned char) to avoid UB

POSIX says:
"The c argument is an int, the value of which the application shall ensure is a
character representable as an unsigned char or equal to the value of the macro
EOF. If the argument has any other value, the behavior is undefined."

Many libc cast implicitly the value, but NetBSD for example does not, which is
probably the correct thing to interpret it.

Diffstat:
M
sic.c
 | 
2
+-
M
util.c
 | 
4
++--

2 files changed, 3 insertions(+), 3 deletions(-)
diff --git a/sic.c b/sic.c
@@ -74,7 +74,7 @@ parsein(char *s) {
 		return;
 	}
 	c = *++s;
-	if(c != '\0' && isspace(s[1])) {
+	if(c != '\0' && isspace((unsigned char)s[1])) {
 		p = s + 2;
 		switch(c) {
 		case 'j':
diff --git a/util.c b/util.c
@@ -42,7 +42,7 @@ dial(char *host, char *port) {
 
 static char *
 eat(char *s, int (*p)(int), int r) {
-	while(*s != '\0' && p(*s) == r)
+	while(*s != '\0' && p((unsigned char)*s) == r)
 		s++;
 	return s;
 }
@@ -61,7 +61,7 @@ trim(char *s) {
 	char *e;
 
 	e = s + strlen(s) - 1;
-	while(e > s && isspace(*e))
+	while(e > s && isspace((unsigned char)*e))
 		e--;
 	*(e + 1) = '\0';
 }