commit 2140c6ec5634ddee572383944f0903ab7b0b829f
from: Omar Polo <op@omarpolo.com>
via: Thomas Adam <thomas@xteddy.org>
date: Mon Jul 04 09:53:09 2022 UTC

check for specific chars instead of using isspace(3)

Reminded by naddy and stsp; it was missing a cast to unsigned char to
prevent issues on archs with signed chars and was too broad anyway.

While here, drop an extra check immediately after.

ok stsp@

commit - ef0f20a88731571e4b4e9152da6cd4d9aac43c49
commit + 2140c6ec5634ddee572383944f0903ab7b0b829f
blob - b31d5584f4116afe5c9013b0835142aedde7d5e2
blob + 82486de5473461070b3bc25188144766e945a929
--- lib/patch.c
+++ lib/patch.c
@@ -412,11 +412,11 @@ linecmp(const char *a, const char *b, int *mangled)
 
 	*mangled = 1;
 	for (;;) {
-		while (isspace(*a))
+		while (*a == '\t' || *a == ' ' || *a == '\f')
 			a++;
-		while (isspace(*b))
+		while (*b == '\t' || *b == ' ' || *b == '\f')
 			b++;
-		if (*a == '\0' || *b == '\0' || *a != *b)
+		if (*a == '\0' || *a != *b)
 			break;
 		a++, b++;
 	}