[Feature] Optimize strlcpy for aligned input

diff --git a/src/libutil/str_util.c b/src/libutil/str_util.c
index 601a3248797e220f29335fa6bfa518cea6f4e2d4..efffe8cc65a2d8dcf369d6777ca1fdb64f784780 100644 (file)
--- a/src/libutil/str_util.c
+++ b/src/libutil/str_util.c
@@ -307,27 +307,44 @@ rspamd_gstring_icase_hash (gconstpointer key)
        return rspamd_icase_hash (f->str, f->len);
 }
 
+#define MEM_ALIGN (sizeof(gsize)-1)
+#define ONES ((size_t)-1/UCHAR_MAX)
+#define HIGHS (ONES * (UCHAR_MAX/2+1))
+#define HASZERO(x) ((x)-ONES & ~(x) & HIGHS)
+
 gsize
 rspamd_strlcpy (gchar *dst, const gchar *src, gsize siz)
 {
        gchar *d = dst;
        const gchar *s = src;
        gsize n = siz;
+       gsize *wd;
+       const gsize *ws;
 
        /* Copy as many bytes as will fit */
        if (n != 0) {
-               while (--n != 0) {
-                       if ((*d++ = *s++) == '\0') {
-                               break;
+               if (((uintptr_t) s & MEM_ALIGN) == ((uintptr_t) d & MEM_ALIGN)) {
+                       for (; ((uintptr_t) s & MEM_ALIGN) && n && (*d = *s); n--, s++, d++);
+                       if (n && *s) {
+                               wd = (void *) d;
+                               ws = (const void *) s;
+                               for (; n >= sizeof (gsize) && !HASZERO(*ws);
+                                          n -= sizeof (gsize), ws++, wd++)
+                                       *wd = *ws;
+                               d = (void *) wd;
+                               s = (const void *) ws;
                        }
                }
-       }
 
-       if (n == 0 && siz != 0) {
-               *d = '\0';
+               for (; n && (*d = *s); n--, s++, d++);
+
+               *d = 0;
+       }
+       else {
+               return 0;
        }
 
-       return (s - src - 1);    /* count does not include NUL */
+       return (d - dst);
 }
 
 gsize