Reland "Cleanup some numeric code.""

core/src/fpdfapi/fpdf_font/fpdf_font_cid.cpp

Index: core/src/fpdfapi/fpdf_font/fpdf_font_cid.cpp
diff --git a/core/src/fpdfapi/fpdf_font/fpdf_font_cid.cpp b/core/src/fpdfapi/fpdf_font/fpdf_font_cid.cpp
index 65b4b781b1411c188f7990f42eb4f39f23ec4f21..d4c71085a1af2f7f16de2c425e027b1c9be5e9db 100644
--- a/core/src/fpdfapi/fpdf_font/fpdf_font_cid.cpp
+++ b/core/src/fpdfapi/fpdf_font/fpdf_font_cid.cpp
@@ -9,6 +9,7 @@
 #include "core/include/fpdfapi/fpdf_module.h"
 #include "core/include/fpdfapi/fpdf_page.h"
 #include "core/include/fpdfapi/fpdf_resource.h"
+#include "core/include/fxcrt/fx_ext.h"
 #include "core/include/fxge/fx_freetype.h"
 #include "core/include/fxge/fx_ge.h"
 #include "core/src/fpdfapi/fpdf_cmaps/cmap_int.h"
@@ -699,30 +700,17 @@ void CPDF_CMapParser::ParseWord(const CFX_ByteStringC& word) {
   m_LastWord = word;
 }
 
+// Static.
 FX_DWORD CPDF_CMapParser::CMap_GetCode(const CFX_ByteStringC& word) {
   int num = 0;
   if (word.GetAt(0) == '<') {
-    for (int i = 1; i < word.GetLength(); i++) {
-      uint8_t digit = word.GetAt(i);
-      if (digit >= '0' && digit <= '9') {
-        digit = digit - '0';
-      } else if (digit >= 'a' && digit <= 'f') {
-        digit = digit - 'a' + 10;
-      } else if (digit >= 'A' && digit <= 'F') {
-        digit = digit - 'A' + 10;
-      } else {
-        return num;
-      }
-      num = num * 16 + digit;
-    }
-  } else {
-    for (int i = 0; i < word.GetLength(); i++) {
-      if (word.GetAt(i) < '0' || word.GetAt(i) > '9') {
-        return num;
-      }
-      num = num * 10 + word.GetAt(i) - '0';
-    }
+    for (int i = 1; i < word.GetLength() && std::isxdigit(word.GetAt(i)); ++i)
+      num = num * 16 + FXSYS_toHexDigit(word.GetAt(i));
+    return num;
   }
+
+  for (int i = 0; i < word.GetLength() && std::isdigit(word.GetAt(i)); ++i)
+    num = num * 10 + FXSYS_toDecimalDigit(word.GetAt(i));
   return num;
 }
 
@@ -746,13 +734,7 @@ bool CPDF_CMapParser::CMap_GetCodeRange(CMap_CodeRange& range,
   for (i = 0; i < range.m_CharSize; ++i) {
     uint8_t digit1 = first.GetAt(i * 2 + 1);
     uint8_t digit2 = first.GetAt(i * 2 + 2);
-    uint8_t byte = (digit1 >= '0' && digit1 <= '9')
-                       ? (digit1 - '0')
-                       : ((digit1 & 0xdf) - 'A' + 10);
-    byte = byte * 16 + ((digit2 >= '0' && digit2 <= '9')
-                            ? (digit2 - '0')
-                            : ((digit2 & 0xdf) - 'A' + 10));
-    range.m_Lower[i] = byte;
+    range.m_Lower[i] = FXSYS_toHexDigit(digit1) * 16 + FXSYS_toHexDigit(digit2);
   }
 
   FX_DWORD size = second.GetLength();
@@ -763,13 +745,7 @@ bool CPDF_CMapParser::CMap_GetCodeRange(CMap_CodeRange& range,
     uint8_t digit2 = ((FX_DWORD)i * 2 + 2 < size)
                          ? second.GetAt((FX_STRSIZE)i * 2 + 2)
                          : '0';
-    uint8_t byte = (digit1 >= '0' && digit1 <= '9')
-                       ? (digit1 - '0')
-                       : ((digit1 & 0xdf) - 'A' + 10);
-    byte = byte * 16 + ((digit2 >= '0' && digit2 <= '9')
-                            ? (digit2 - '0')
-                            : ((digit2 & 0xdf) - 'A' + 10));
-    range.m_Upper[i] = byte;
+    range.m_Upper[i] = FXSYS_toHexDigit(digit1) * 16 + FXSYS_toHexDigit(digit2);
   }
   return true;
 }