3 files changed, 29 insertions, 25 deletions

diff --git a/src/string/strchr.c b/src/string/strchr.c
index d3563f18..bfae8f9f 100644
--- a/src/string/strchr.c
+++ b/src/string/strchr.c
@@ -1,26 +1,9 @@
 #include <string.h>
-#include <stdlib.h>
-#include <stdint.h>
-#include <limits.h>
 
-#define ALIGN (sizeof(size_t)-1)
-#define ONES ((size_t)-1/UCHAR_MAX)
-#define HIGHS (ONES * (UCHAR_MAX/2+1))
-#define HASZERO(x) ((x)-ONES & ~(x) & HIGHS)
+char *__strchrnul(const char *, int);
 
 char *strchr(const char *s, int c)
 {
-	size_t *w, k;
-
-	c = (unsigned char)c;
-	if (!c) return (char *)s + strlen(s);
-
-	for (; ((uintptr_t)s & ALIGN); s++)
-		if (*(unsigned char *)s == c) return (char *)s;
-		else if (!*s) return 0;
-	k = ONES * c;
-	for (w = (void *)s; !HASZERO(*w) && !HASZERO(*w^k); w++);
-	for (s = (void *)w; *s; s++)
-		if (*(unsigned char *)s == c) return (char *)s;
-	return 0;
+	char *r = __strchrnul(s, c);
+	return *(unsigned char *)r == (unsigned char)c ? r : 0;
 }
diff --git a/src/string/strchrnul.c b/src/string/strchrnul.c
index 5e0c1a1a..ceae4d45 100644
--- a/src/string/strchrnul.c
+++ b/src/string/strchrnul.c
@@ -1,7 +1,27 @@
 #include <string.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <limits.h>
+#include "libc.h"
 
-char *strchrnul(const char *s, int c)
+#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)
+
+char *__strchrnul(const char *s, int c)
 {
-	char *p = strchr(s, c);
-	return p ? p : (char *)s + strlen(s);
+	size_t *w, k;
+
+	c = (unsigned char)c;
+	if (!c) return (char *)s + strlen(s);
+
+	for (; (uintptr_t)s % ALIGN; s++)
+		if (!*s || *(unsigned char *)s == c) return (char *)s;
+	k = ONES * c;
+	for (w = (void *)s; !HASZERO(*w) && !HASZERO(*w^k); w++);
+	for (s = (void *)w; *s && *(unsigned char *)s != c; s++);
+	return (char *)s;
 }
+
+weak_alias(__strchrnul, strchrnul);
diff --git a/src/string/strcspn.c b/src/string/strcspn.c
index c843ff97..cfdba114 100644
--- a/src/string/strcspn.c
+++ b/src/string/strcspn.c
@@ -3,13 +3,14 @@
 #define BITOP(a,b,op) \
  ((a)[(size_t)(b)/(8*sizeof *(a))] op (size_t)1<<((size_t)(b)%(8*sizeof *(a))))
 
+char *__strchrnul(const char *, int);
+
 size_t strcspn(const char *s, const char *c)
 {
 	const char *a = s;
 	size_t byteset[32/sizeof(size_t)];
 
-	if (!c[0]) return strlen(s);
-	if (!c[1]) return (s=strchr(s, *c)) ? s-a : strlen(a);
+	if (!c[0] || !c[1]) return __strchrnul(s, *c)-a;
 
 	memset(byteset, 0, sizeof byteset);
 	for (; *c && BITOP(byteset, *(unsigned char *)c, |=); c++);