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, 13 insertions, 14 deletions

diff --git a/xfa/fxfa/parser/cxfa_widgetdata.cpp b/xfa/fxfa/parser/cxfa_widgetdata.cpp
index 5efc0ea481..34e3aeaf0f 100644
--- a/xfa/fxfa/parser/cxfa_widgetdata.cpp
+++ b/xfa/fxfa/parser/cxfa_widgetdata.cpp
@@ -42,11 +42,10 @@ bool SplitDateTime(const CFX_WideString& wsDateTime,
   if (wsDateTime.IsEmpty())
     return false;
 
-  int nSplitIndex = -1;
-  nSplitIndex = wsDateTime.Find('T');
-  if (nSplitIndex < 0)
+  FX_STRSIZE nSplitIndex = wsDateTime.Find('T');
+  if (nSplitIndex == FX_STRNPOS)
     nSplitIndex = wsDateTime.Find(' ');
-  if (nSplitIndex < 0)
+  if (nSplitIndex == FX_STRNPOS)
     return false;
 
   wsDate = wsDateTime.Left(nSplitIndex);
@@ -848,17 +847,17 @@ std::vector<CFX_WideString> CXFA_WidgetData::GetSelectedItemsValue() {
   CFX_WideString wsValue = GetRawValue();
   if (GetChoiceListOpen() == XFA_ATTRIBUTEENUM_MultiSelect) {
     if (!wsValue.IsEmpty()) {
-      int32_t iStart = 0;
-      int32_t iLength = wsValue.GetLength();
-      int32_t iEnd = wsValue.Find(L'\n', iStart);
-      iEnd = (iEnd == -1) ? iLength : iEnd;
+      FX_STRSIZE iStart = 0;
+      FX_STRSIZE iLength = wsValue.GetLength();
+      FX_STRSIZE iEnd = wsValue.Find(L'\n', iStart);
+      iEnd = (iEnd == FX_STRNPOS) ? iLength : iEnd;
       while (iEnd >= iStart) {
         wsSelTextArray.push_back(wsValue.Mid(iStart, iEnd - iStart));
         iStart = iEnd + 1;
         if (iStart >= iLength)
           break;
         iEnd = wsValue.Find(L'\n', iStart);
-        if (iEnd < 0)
+        if (iEnd == FX_STRNPOS)
           wsSelTextArray.push_back(wsValue.Mid(iStart, iLength - iStart));
       }
     }
@@ -1318,7 +1317,7 @@ bool CXFA_WidgetData::GetBarcodeAttribute_WideNarrowRatio(float* val) {
   if (pUIChild->TryCData(XFA_ATTRIBUTE_WideNarrowRatio, wsWideNarrowRatio)) {
     FX_STRSIZE ptPos = wsWideNarrowRatio.Find(':');
     float fRatio = 0;
-    if (ptPos >= 0) {
+    if (ptPos != FX_STRNPOS) {
       fRatio = (float)FXSYS_wtoi(wsWideNarrowRatio.c_str());
     } else {
       int32_t fA, fB;
@@ -1743,9 +1742,9 @@ void CXFA_WidgetData::NormalizeNumStr(const CFX_WideString& wsValue,
 
   wsOutput = wsValue;
   wsOutput.TrimLeft('0');
-  int32_t dot_index = wsOutput.Find('.');
+  FX_STRSIZE dot_index = wsOutput.Find('.');
   int32_t iFracDigits = 0;
-  if (!wsOutput.IsEmpty() && dot_index >= 0 &&
+  if (!wsOutput.IsEmpty() && dot_index != FX_STRNPOS &&
       (!GetFracDigits(iFracDigits) || iFracDigits != -1)) {
     wsOutput.TrimRight(L"0");
     wsOutput.TrimRight(L".");
@@ -1769,8 +1768,8 @@ void CXFA_WidgetData::FormatNumStr(const CFX_WideString& wsValue,
     wsSrcNum.Delete(0, 1);
   }
   int32_t len = wsSrcNum.GetLength();
-  int32_t dot_index = wsSrcNum.Find('.');
-  if (dot_index == -1)
+  FX_STRSIZE dot_index = wsSrcNum.Find('.');
+  if (dot_index == FX_STRNPOS)
     dot_index = len;
 
   int32_t cc = dot_index - 1;