[PATCH 4/4] String: refactor to utilize word.h and always terminate string

[Nathan McSween <nwmcsween@gmail.com>]

---
 src/string/strlcpy.c | 56 ++++++++++++++++++++++++++++++----------------------
 1 file changed, 32 insertions(+), 24 deletions(-)

diff --git a/src/string/strlcpy.c b/src/string/strlcpy.c
index 4d3ff92..bc26441 100644
--- a/src/string/strlcpy.c
+++ b/src/string/strlcpy.c
@@ -1,32 +1,40 @@
-#include <string.h>
-#include <stdlib.h>
+#include <stddef.h>
 #include <stdint.h>
-#include <limits.h>
-#include "libc.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)
+#include <string.h>
+#include "word.h"
 
+/**
+ * strlcpy - Word sized bsd strlcpy.
+ * @d: Destination
+ * @s: Source
+ * @n: Max @s
+ */
 size_t strlcpy(char *d, const char *s, size_t n)
 {
-	char *d0 = d;
+	char *z = d;
 	size_t *wd;
 	const size_t *ws;
 
-	if (!n--) goto finish;
-	if (((uintptr_t)s & ALIGN) == ((uintptr_t)d & ALIGN)) {
-		for (; ((uintptr_t)s & ALIGN) && n && (*d=*s); n--, s++, d++);
-		if (n && *s) {
-			wd=(void *)d; ws=(const void *)s;
-			for (; n>=sizeof(size_t) && !HASZERO(*ws);
-			       n-=sizeof(size_t), ws++, wd++) *wd = *ws;
-			d=(void *)wd; s=(const void *)ws;
-		}
-	}
-	for (; n && (*d=*s); n--, s++, d++);
-	*d = 0;
-finish:
-	return d-d0 + strlen(s);
+	/* A byte for nul */
+	if (!n--) goto terminate;
+
+	if ((uintptr_t)d % sizeof(size_t) != (uintptr_t)s % sizeof(size_t))
+		goto misaligned;
+
+	for (; (uintptr_t)s % sizeof(size_t); *d++ = *s++, n--)
+		if (!*s || !n) goto terminate;
+
+	for (wd = (size_t *)d, ws= (const size_t *)s
+	     ; !word_has_zero(*ws) && n >= sizeof(size_t)
+	     ; *wd = *ws, wd++, ws++, n -= sizeof(size_t))
+
+	d = (char *)wd;
+	s = (const char *)ws;
+
+misaligned:
+	for (; (*d = *s) && n; d++, s++, n--);
+terminate:
+	*d = '\0';
+
+	return d - z + strlen(s);
 }
-- 
1.7.11.4