[4/9] richedit: Improve efficiency of ME_IsCandidateAnURL.

[Dylan Smith]

The code was previously getting the same text in the loop from the
editor, and it was converting each of the prefixes to compare against
for each URL candidate.  This seemed unnecessary, so this patch cleans
up the function to make it more efficient.
---
 dlls/riched20/editor.c |   62 ++++++++++++++++++++---------------------------
 1 files changed, 26 insertions(+), 36 deletions(-)
-------------- next part --------------
diff --git a/dlls/riched20/editor.c b/dlls/riched20/editor.c
index 79f6be2..c326ae8 100644
--- a/dlls/riched20/editor.c
+++ b/dlls/riched20/editor.c
@@ -4766,51 +4766,38 @@ static BOOL ME_FindNextURLCandidate(ME_TextEditor *editor, int sel_min, int sel_
 /**
  * This proc evaluates the selection and returns TRUE if it can be considered an URL
  */
-static BOOL ME_IsCandidateAnURL(ME_TextEditor *editor, int sel_min, int sel_max)
+static BOOL ME_IsCandidateAnURL(ME_TextEditor *editor, const ME_Cursor *start, int nChars)
 {
+#define MAX_PREFIX_LEN 9
   struct prefix_s {
-    const char *text;
+    const WCHAR text[MAX_PREFIX_LEN];
     int length;
-  } prefixes[12] = {
-    /* Code below depends on these being in decreasing length order! */
-    {"prospero:", 10},
-    {"telnet:", 8},
-    {"gopher:", 8},
-    {"mailto:", 8},
-    {"https:", 7},
-    {"file:", 6},
-    {"news:", 6},
-    {"wais:", 6},
-    {"nntp:", 6},
-    {"http:", 5},
-    {"www.", 5},
-    {"ftp:", 5},
+  }prefixes[] = {
+    {{'p','r','o','s','p','e','r','o',':'}, 9},
+    {{'t','e','l','n','e','t',':'}, 7},
+    {{'g','o','p','h','e','r',':'}, 7},
+    {{'m','a','i','l','t','o',':'}, 7},
+    {{'h','t','t','p','s',':'}, 6},
+    {{'f','i','l','e',':'}, 5},
+    {{'n','e','w','s',':'}, 5},
+    {{'w','a','i','s',':'}, 5},
+    {{'n','n','t','p',':'}, 5},
+    {{'h','t','t','p',':'}, 5},
+    {{'w','w','w','.'}, 4},
+    {{'f','t','p',':'}, 4},
   };
-  LPWSTR bufferW = NULL;
-  WCHAR bufW[32];
+  WCHAR bufferW[MAX_PREFIX_LEN + 1];
   unsigned int i;
-  ME_Cursor sel_start;
 
-  ME_CursorFromCharOfs(editor, sel_min, &sel_start);
-  if (sel_max == -1) sel_max = ME_GetTextLength(editor);
-  assert(sel_min <= sel_max);
-  for (i = 0; i < sizeof(prefixes) / sizeof(struct prefix_s); i++)
+  ME_GetTextW(editor, bufferW, MAX_PREFIX_LEN, start, nChars, 0);
+  for (i = 0; i < sizeof(prefixes) / sizeof(*prefixes); i++)
   {
-    if (sel_max - sel_min < prefixes[i].length) continue;
-    if (bufferW == NULL) {
-      bufferW = heap_alloc((sel_max - sel_min + 1) * sizeof(WCHAR));
-    }
-    ME_GetTextW(editor, bufferW, sel_max - sel_min, &sel_start,
-                lstrlenA(prefixes[i].text), 0);
-    MultiByteToWideChar(CP_ACP, 0, prefixes[i].text, -1, bufW, 32);
-    if (!lstrcmpW(bufW, bufferW))
-    {
-      heap_free(bufferW);
+    if (nChars < prefixes[i].length) continue;
+    if (!memcmp(prefixes[i].text, bufferW, prefixes[i].length * sizeof(WCHAR)))
       return TRUE;
-    }
   }
-  heap_free(bufferW);
   return FALSE;
+#undef MAX_PREFIX_LEN
 }
 
 /**
@@ -4837,11 +4824,14 @@ static BOOL ME_UpdateLinkAttribute(ME_TextEditor *editor, int sel_min, int sel_m
 
     if (ME_FindNextURLCandidate(editor, sel_min, sel_max, &cMin, &cMax))
     {
+      ME_Cursor candidateStart;
       /* Section before candidate is not an URL */
       beforeURL[0] = sel_min;
       beforeURL[1] = cMin;
 
-      if (ME_IsCandidateAnURL(editor, cMin, cMax))
+      ME_CursorFromCharOfs(editor, cMin, &candidateStart);
+      if (ME_IsCandidateAnURL(editor, &candidateStart,
+                              (cMax == -1 ? INT_MAX : cMax) - cMin))
       {
         inURL[0] = cMin; inURL[1] = cMax;
       }