fix undefined behavior in free

[oweals/musl.git] / src / string / strlen.c

diff --git a/src/string/strlen.c b/src/string/strlen.c
index 936fb5cf56da2d00f3947d0aed2644a9397daef8..929ddcbc1c2594762c7b44cdfd5edf0f2955d1f6 100644 (file)
--- a/src/string/strlen.c
+++ b/src/string/strlen.c
@@ -1,9 +1,8 @@
 #include <string.h>
-#include <stdlib.h>
 #include <stdint.h>
 #include <limits.h>
 
-#define ALIGN (sizeof(size_t)-1)
+#define ALIGN (sizeof(size_t))
 #define ONES ((size_t)-1/UCHAR_MAX)
 #define HIGHS (ONES * (UCHAR_MAX/2+1))
 #define HASZERO(x) ((x)-ONES & ~(x) & HIGHS)
@@ -12,10 +11,8 @@ size_t strlen(const char *s)
 {
        const char *a = s;
        const size_t *w;
-       for (; ((uintptr_t)s & ALIGN) && *s; s++);
-       if (*s) {
-               for (w = (const void *)s; !HASZERO(*w); w++);
-               for (s = (const void *)w; *s; s++);
-       }
+       for (; (uintptr_t)s % ALIGN; s++) if (!*s) return s-a;
+       for (w = (const void *)s; !HASZERO(*w); w++);
+       for (s = (const void *)w; *s; s++);
        return s-a;
 }