Adjust loops in preperation for FX_STRSIZE int->size_t

Adjust loop conditions and behaviours in preperation for convering the
underlying type of FX_STRSIZE to size_t. These changes are not
dependent on the type switch occuring, so can be landed before hand.

BUG=pdfium:828

Change-Id: I5f950c99c10e5ef0836959e3b1dd2e09f8f5afc0
Reviewed-on: https://pdfium-review.googlesource.com/12750
Commit-Queue: Ryan Harrison <rharrison@chromium.org>
Reviewed-by: Henrique Nakashima <hnakashima@chromium.org>

1 files changed, 6 insertions, 6 deletions

diff --git a/core/fpdftext/cpdf_linkextract.cpp b/core/fpdftext/cpdf_linkextract.cpp
index 880a4ceb92..a5eafe689a 100644
--- a/core/fpdftext/cpdf_linkextract.cpp
+++ b/core/fpdftext/cpdf_linkextract.cpp
@@ -245,24 +245,24 @@ bool CPDF_LinkExtract::CheckMailLink(CFX_WideString* str) {
 
   // Check the local part.
   FX_STRSIZE pPos = aPos.value();  // Used to track the position of '@' or '.'.
-  for (FX_STRSIZE i = aPos.value() - 1; i >= 0; i--) {
-    wchar_t ch = (*str)[i];
+  for (FX_STRSIZE i = aPos.value(); i > 0; i--) {
+    wchar_t ch = (*str)[i - 1];
     if (ch == L'_' || ch == L'-' || FXSYS_iswalnum(ch))
       continue;
 
-    if (ch != L'.' || i == pPos - 1 || i == 0) {
-      if (i == aPos.value() - 1) {
+    if (ch != L'.' || i == pPos || i == 1) {
+      if (i == aPos.value()) {
         // There is '.' or invalid char before '@'.
         return false;
       }
       // End extracting for other invalid chars, '.' at the beginning, or
       // consecutive '.'.
-      FX_STRSIZE removed_len = i == pPos - 1 ? i + 2 : i + 1;
+      FX_STRSIZE removed_len = i == pPos ? i + 1 : i;
       *str = str->Right(str->GetLength() - removed_len);
       break;
     }
     // Found a valid '.'.
-    pPos = i;
+    pPos = i - 1;
   }
 
   // Check the domain name part.