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, 3 insertions, 3 deletions

diff --git a/core/fxge/cfx_fontmapper.cpp b/core/fxge/cfx_fontmapper.cpp
index 4c0073ab73..b8ffe047a3 100644
--- a/core/fxge/cfx_fontmapper.cpp
+++ b/core/fxge/cfx_fontmapper.cpp
@@ -172,7 +172,7 @@ const struct CODEPAGE_MAP {
 int CompareFontFamilyString(const void* key, const void* element) {
   CFX_ByteString str_key((const char*)key);
   const AltFontFamily* family = reinterpret_cast<const AltFontFamily*>(element);
-  if (str_key.Find(family->m_pFontName) != -1)
+  if (str_key.Find(family->m_pFontName) != FX_STRNPOS)
     return 0;
   return FXSYS_stricmp(reinterpret_cast<const char*>(key), family->m_pFontName);
 }
@@ -187,8 +187,8 @@ CFX_ByteString TT_NormalizeName(const char* family) {
   norm.Remove(' ');
   norm.Remove('-');
   norm.Remove(',');
-  int pos = norm.Find('+');
-  if (pos > 0)
+  FX_STRSIZE pos = norm.Find('+');
+  if (pos != 0 && pos != FX_STRNPOS)
     norm = norm.Left(pos);
   norm.MakeLower();
   return norm;