Replace raw value for constant error value in string operations

Currently Find() and other methods that return a FX_STRSIZE return -1
to indicate error/failure. This means that there is a lot of magic
numbers and magic checks floating around. The standard library for
similar operations uses a npos constant. This CL implements
FX_STRNPOS, and replaces usages of magic number checking. It also does
some type cleanup along the way where it was obvious that FX_STRSIZE
should be being used.

Removing the magic numbers should make eventually changing FX_STRSIZE
to be unsigned easier in the future.

BUG=pdfium:828

Change-Id: I67e481e44cf2f75a1698afa8fbee4f375a74c490
Reviewed-on: https://pdfium-review.googlesource.com/9651
Commit-Queue: Ryan Harrison <rharrison@chromium.org>
Reviewed-by: Tom Sepez <tsepez@chromium.org>

1 files changed, 5 insertions, 5 deletions

diff --git a/xfa/fxfa/parser/cxfa_node.cpp b/xfa/fxfa/parser/cxfa_node.cpp
index 261fee1971..8497e60a74 100644
--- a/xfa/fxfa/parser/cxfa_node.cpp
+++ b/xfa/fxfa/parser/cxfa_node.cpp
@@ -4043,10 +4043,10 @@ bool CXFA_Node::SetScriptContent(const CFX_WideString& wsContent,
           std::vector<CFX_WideString> wsSaveTextArray;
           size_t iSize = 0;
           if (!wsContent.IsEmpty()) {
-            int32_t iStart = 0;
-            int32_t iLength = wsContent.GetLength();
-            int32_t iEnd = wsContent.Find(L'\n', iStart);
-            iEnd = (iEnd == -1) ? iLength : iEnd;
+            FX_STRSIZE iStart = 0;
+            FX_STRSIZE iLength = wsContent.GetLength();
+            FX_STRSIZE iEnd = wsContent.Find(L'\n', iStart);
+            iEnd = (iEnd == FX_STRNPOS) ? iLength : iEnd;
             while (iEnd >= iStart) {
               wsSaveTextArray.push_back(wsContent.Mid(iStart, iEnd - iStart));
               iStart = iEnd + 1;
@@ -4054,7 +4054,7 @@ bool CXFA_Node::SetScriptContent(const CFX_WideString& wsContent,
                 break;
               }
               iEnd = wsContent.Find(L'\n', iStart);
-              if (iEnd < 0) {
+              if (iEnd == FX_STRNPOS) {
                 wsSaveTextArray.push_back(
                     wsContent.Mid(iStart, iLength - iStart));
               }