commit 2d014eee3ebcc12d83998f0c65adee935cf09229
author Tom Sepez <tsepez@chromium.org> Wed Dec 15 22:43:43 2021 +0000
committer Pdfium LUCI CQ <pdfium-scoped@luci-project-accounts.iam.gserviceaccount.com> Wed Dec 15 22:43:43 2021 +0000
tree 8c68809447f29eb8f4806925990ac9e700d02615
parent bafc408dc3010c48b105f852901b2a2a9659f89e

Append in-place in ExportEncodeAttribute()

Avoid copying from a text buf to a widestring, then from that widestring
onto the end of another widestring. Unfortunately requires wide literals
since wide strings don't have an AppendASCII() method (yet).

Change-Id: I57c613942baa9b7f9ac81d40b191351265d06ea1
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/88090
Reviewed-by: Lei Zhang <thestig@chromium.org>
Commit-Queue: Tom Sepez <tsepez@chromium.org>

xfa/fxfa/parser/xfa_utils.cpp

diff --git a/xfa/fxfa/parser/xfa_utils.cpp b/xfa/fxfa/parser/xfa_utils.cpp
index 2f199cf..b69e9a4 100644
--- a/xfa/fxfa/parser/xfa_utils.cpp
+++ b/xfa/fxfa/parser/xfa_utils.cpp
@@ -31,31 +31,28 @@
 
 const char kFormNS[] = "http://www.xfa.org/schema/xfa-form/";
 
-WideString ExportEncodeAttribute(const WideString& str) {
-  CFX_WideTextBuf textBuf;
-  int32_t iLen = str.GetLength();
-  for (int32_t i = 0; i < iLen; i++) {
+void ExportEncodeAttribute(const WideString& str, WideString& textBuf) {
+  for (size_t i = 0; i < str.GetLength(); i++) {
     switch (str[i]) {
       case '&':
-        textBuf << "&amp;";
+        textBuf += L"&amp;";
         break;
       case '<':
-        textBuf << "&lt;";
+        textBuf += L"&lt;";
         break;
       case '>':
-        textBuf << "&gt;";
+        textBuf += L"&gt;";
         break;
       case '\'':
-        textBuf << "&apos;";
+        textBuf += L"&apos;";
         break;
       case '\"':
-        textBuf << "&quot;";
+        textBuf += L"&quot;";
         break;
       default:
-        textBuf.AppendChar(str[i]);
+        textBuf += str[i];
     }
   }
-  return textBuf.MakeString();
 }
 
 bool IsXMLValidChar(wchar_t ch) {
@@ -148,7 +145,7 @@
   wsOutput += L" ";
   wsOutput += wsName;
   wsOutput += L"=\"";
-  wsOutput += ExportEncodeAttribute(value.value());
+  ExportEncodeAttribute(value.value(), wsOutput);
   wsOutput += L"\"";
 }