Merge to XFA: Reland "Cleanup some numeric code.""

This reverts commit 0569ab0b11b723d9bca4ddd642b0cf8828c4bdd1.

This changes the various comparisons of char >= '0' && char <= '9' and
char < '0' || char > '9' to use std::isdigit checks. It also cleans up
a handful of hex to digit conversions to call one common method.

R=tsepez@chromium.org

Review URL: https://codereview.chromium.org/1449873003 .

(cherry picked from commit 3f148915d12f54a946a0c0bf526162b79c39d650)

Review URL: https://codereview.chromium.org/1452673002 .

2 files changed, 23 insertions, 72 deletions

diff --git a/core/src/fpdfapi/fpdf_font/fpdf_font.cpp b/core/src/fpdfapi/fpdf_font/fpdf_font.cpp
index 9f83da062c..64d6cdce92 100644
--- a/core/src/fpdfapi/fpdf_font/fpdf_font.cpp
+++ b/core/src/fpdfapi/fpdf_font/fpdf_font.cpp
@@ -11,6 +11,7 @@
 #include "core/include/fpdfapi/fpdf_page.h"
 #include "core/include/fpdfapi/fpdf_pageobj.h"
 #include "core/include/fpdfapi/fpdf_resource.h"
+#include "core/include/fxcrt/fx_ext.h"
 #include "core/include/fxge/fx_freetype.h"
 
 #if _FXM_PLATFORM_ == _FXM_PLATFORM_APPLE_
@@ -518,32 +519,19 @@ FX_DWORD CPDF_ToUnicodeMap::ReverseLookup(FX_WCHAR unicode) {
 FX_DWORD CPDF_ToUnicodeMap::StringToCode(const CFX_ByteStringC& str) {
   const FX_CHAR* buf = str.GetCStr();
   int len = str.GetLength();
-  if (len == 0) {
+  if (len == 0)
     return 0;
-  }
+
   int result = 0;
   if (buf[0] == '<') {
-    for (int i = 1; i < len; i++) {
-      int digit;
-      if (buf[i] >= '0' && buf[i] <= '9') {
-        digit = buf[i] - '0';
-      } else if (buf[i] >= 'a' && buf[i] <= 'f') {
-        digit = buf[i] - 'a' + 10;
-      } else if (buf[i] >= 'A' && buf[i] <= 'F') {
-        digit = buf[i] - 'A' + 10;
-      } else {
-        break;
-      }
-      result = result * 16 + digit;
-    }
+    for (int i = 1; i < len && std::isxdigit(buf[i]); ++i)
+      result = result * 16 + FXSYS_toHexDigit(buf[i]);
     return result;
   }
-  for (int i = 0; i < len; i++) {
-    if (buf[i] < '0' || buf[i] > '9') {
-      break;
-    }
-    result = result * 10 + buf[i] - '0';
-  }
+
+  for (int i = 0; i < len && std::isdigit(buf[i]); ++i)
+    result = result * 10 + FXSYS_toDecimalDigit(buf[i]);
+
   return result;
 }
 static CFX_WideString StringDataAdd(CFX_WideString str) {
@@ -570,26 +558,15 @@ CFX_WideString CPDF_ToUnicodeMap::StringToWideString(
     const CFX_ByteStringC& str) {
   const FX_CHAR* buf = str.GetCStr();
   int len = str.GetLength();
-  if (len == 0) {
+  if (len == 0)
     return CFX_WideString();
-  }
+
   CFX_WideString result;
   if (buf[0] == '<') {
     int byte_pos = 0;
     FX_WCHAR ch = 0;
-    for (int i = 1; i < len; i++) {
-      int digit;
-      if (buf[i] >= '0' && buf[i] <= '9') {
-        digit = buf[i] - '0';
-      } else if (buf[i] >= 'a' && buf[i] <= 'f') {
-        digit = buf[i] - 'a' + 10;
-      } else if (buf[i] >= 'A' && buf[i] <= 'F') {
-        digit = buf[i] - 'A' + 10;
-      } else {
-        break;
-      }
-      ch = ch * 16 + digit;
-
+    for (int i = 1; i < len && std::isxdigit(buf[i]); ++i) {
+      ch = ch * 16 + FXSYS_toHexDigit(buf[i]);
       byte_pos++;
       if (byte_pos == 4) {
         result += ch;
@@ -599,8 +576,6 @@ CFX_WideString CPDF_ToUnicodeMap::StringToWideString(
     }
     return result;
   }
-  if (buf[0] == '(') {
-  }
   return result;
 }
 void CPDF_ToUnicodeMap::Load(CPDF_Stream* pStream) {
diff --git a/core/src/fpdfapi/fpdf_font/fpdf_font_cid.cpp b/core/src/fpdfapi/fpdf_font/fpdf_font_cid.cpp
index 65b4b781b1..d4c71085a1 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;
 }