[gvg] 17090: Sync to Wine-20050725:

Sync to Wine-20050725:
Alexandre Julliard [e-mail]
- Faster implementation of wcstombs that handles overlapping buffers
  properly (based on a patch by Dmitry Timoshkov).
Modified: trunk/reactos/tools/unicode/wctomb.c
  _____

Modified: trunk/reactos/tools/unicode/wctomb.c
--- trunk/reactos/tools/unicode/wctomb.c	2005-08-05 21:53:20 UTC
(rev 17089)
+++ trunk/reactos/tools/unicode/wctomb.c	2005-08-05 22:24:53 UTC
(rev 17090)
@@ -142,45 +142,52 @@

ret = -1;
     }

-    if (dst <= (const char *)src && dst + 16 > (const char *)src)
+    while (srclen >= 16)
     {
-        /* overlapping buffers, do it char by char */
-        while (srclen--)
-        {
-            *dst++ = uni2cp_low[uni2cp_high[*src >> 8] + (*src &
0xff)];
-            src++;
-        }
-        return ret;
+        dst[0]  = uni2cp_low[uni2cp_high[src[0]  >> 8] + (src[0]  &
0xff)];
+        dst[1]  = uni2cp_low[uni2cp_high[src[1]  >> 8] + (src[1]  &
0xff)];
+        dst[2]  = uni2cp_low[uni2cp_high[src[2]  >> 8] + (src[2]  &
0xff)];
+        dst[3]  = uni2cp_low[uni2cp_high[src[3]  >> 8] + (src[3]  &
0xff)];
+        dst[4]  = uni2cp_low[uni2cp_high[src[4]  >> 8] + (src[4]  &
0xff)];
+        dst[5]  = uni2cp_low[uni2cp_high[src[5]  >> 8] + (src[5]  &
0xff)];
+        dst[6]  = uni2cp_low[uni2cp_high[src[6]  >> 8] + (src[6]  &
0xff)];
+        dst[7]  = uni2cp_low[uni2cp_high[src[7]  >> 8] + (src[7]  &
0xff)];
+        dst[8]  = uni2cp_low[uni2cp_high[src[8]  >> 8] + (src[8]  &
0xff)];
+        dst[9]  = uni2cp_low[uni2cp_high[src[9]  >> 8] + (src[9]  &
0xff)];
+        dst[10] = uni2cp_low[uni2cp_high[src[10] >> 8] + (src[10] &
0xff)];
+        dst[11] = uni2cp_low[uni2cp_high[src[11] >> 8] + (src[11] &
0xff)];
+        dst[12] = uni2cp_low[uni2cp_high[src[12] >> 8] + (src[12] &
0xff)];
+        dst[13] = uni2cp_low[uni2cp_high[src[13] >> 8] + (src[13] &
0xff)];
+        dst[14] = uni2cp_low[uni2cp_high[src[14] >> 8] + (src[14] &
0xff)];
+        dst[15] = uni2cp_low[uni2cp_high[src[15] >> 8] + (src[15] &
0xff)];
+        src += 16;
+        dst += 16;
+        srclen -= 16;
     }

-    for (;;)
+    /* now handle remaining characters */
+    src += srclen;
+    dst += srclen;
+    switch(srclen)
     {
-        switch(srclen)
-        {
-        default:
-        case 16: dst[15] = uni2cp_low[uni2cp_high[src[15] >> 8] +
(src[15] & 0xff)];
-        case 15: dst[14] = uni2cp_low[uni2cp_high[src[14] >> 8] +
(src[14] & 0xff)];
-        case 14: dst[13] = uni2cp_low[uni2cp_high[src[13] >> 8] +
(src[13] & 0xff)];
-        case 13: dst[12] = uni2cp_low[uni2cp_high[src[12] >> 8] +
(src[12] & 0xff)];
-        case 12: dst[11] = uni2cp_low[uni2cp_high[src[11] >> 8] +
(src[11] & 0xff)];
-        case 11: dst[10] = uni2cp_low[uni2cp_high[src[10] >> 8] +
(src[10] & 0xff)];
-        case 10: dst[9]  = uni2cp_low[uni2cp_high[src[9]  >> 8] +
(src[9]  & 0xff)];
-        case 9:  dst[8]  = uni2cp_low[uni2cp_high[src[8]  >> 8] +
(src[8]  & 0xff)];
-        case 8:  dst[7]  = uni2cp_low[uni2cp_high[src[7]  >> 8] +
(src[7]  & 0xff)];
-        case 7:  dst[6]  = uni2cp_low[uni2cp_high[src[6]  >> 8] +
(src[6]  & 0xff)];
-        case 6:  dst[5]  = uni2cp_low[uni2cp_high[src[5]  >> 8] +
(src[5]  & 0xff)];
-        case 5:  dst[4]  = uni2cp_low[uni2cp_high[src[4]  >> 8] +
(src[4]  & 0xff)];
-        case 4:  dst[3]  = uni2cp_low[uni2cp_high[src[3]  >> 8] +
(src[3]  & 0xff)];
-        case 3:  dst[2]  = uni2cp_low[uni2cp_high[src[2]  >> 8] +
(src[2]  & 0xff)];
-        case 2:  dst[1]  = uni2cp_low[uni2cp_high[src[1]  >> 8] +
(src[1]  & 0xff)];
-        case 1:  dst[0]  = uni2cp_low[uni2cp_high[src[0]  >> 8] +
(src[0]  & 0xff)];
-        case 0: break;
-        }
-        if (srclen < 16) return ret;
-        dst += 16;
-        src += 16;
-        srclen -= 16;
+    case 15: dst[-15] = uni2cp_low[uni2cp_high[src[-15] >> 8] +
(src[-15] & 0xff)];
+    case 14: dst[-14] = uni2cp_low[uni2cp_high[src[-14] >> 8] +
(src[-14] & 0xff)];
+    case 13: dst[-13] = uni2cp_low[uni2cp_high[src[-13] >> 8] +
(src[-13] & 0xff)];
+    case 12: dst[-12] = uni2cp_low[uni2cp_high[src[-12] >> 8] +
(src[-12] & 0xff)];
+    case 11: dst[-11] = uni2cp_low[uni2cp_high[src[-11] >> 8] +
(src[-11] & 0xff)];
+    case 10: dst[-10] = uni2cp_low[uni2cp_high[src[-10] >> 8] +
(src[-10] & 0xff)];
+    case 9:  dst[-9]  = uni2cp_low[uni2cp_high[src[-9]  >> 8] +
(src[-9]  & 0xff)];
+    case 8:  dst[-8]  = uni2cp_low[uni2cp_high[src[-8]  >> 8] +
(src[-8]  & 0xff)];
+    case 7:  dst[-7]  = uni2cp_low[uni2cp_high[src[-7]  >> 8] +
(src[-7]  & 0xff)];
+    case 6:  dst[-6]  = uni2cp_low[uni2cp_high[src[-6]  >> 8] +
(src[-6]  & 0xff)];
+    case 5:  dst[-5]  = uni2cp_low[uni2cp_high[src[-5]  >> 8] +
(src[-5]  & 0xff)];
+    case 4:  dst[-4]  = uni2cp_low[uni2cp_high[src[-4]  >> 8] +
(src[-4]  & 0xff)];
+    case 3:  dst[-3]  = uni2cp_low[uni2cp_high[src[-3]  >> 8] +
(src[-3]  & 0xff)];
+    case 2:  dst[-2]  = uni2cp_low[uni2cp_high[src[-2]  >> 8] +
(src[-2]  & 0xff)];
+    case 1:  dst[-1]  = uni2cp_low[uni2cp_high[src[-1]  >> 8] +
(src[-1]  & 0xff)];
+    case 0: break;
     }
+    return ret;
 }

/* slow version of wcstombs_sbcs that handles the various flags */