fgas/ code cleanup.

xfa/fxfa/app/xfa_ffdoc.cpp

 // Copyright 2014 PDFium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
 
 #include "xfa/fxfa/include/xfa_ffdoc.h"
 
 #include <algorithm>
 
 #include "core/fpdfapi/fpdf_parser/include/cpdf_array.h"
 #include "core/fpdfapi/fpdf_parser/include/cpdf_document.h"
 #include "core/fpdfdoc/include/fpdf_doc.h"
 #include "core/fxcrt/include/fx_ext.h"
 #include "core/fxcrt/include/fx_memory.h"
 #include "xfa/fde/xml/fde_xml_imp.h"
-#include "xfa/fgas/crt/fgas_algorithm.h"
 #include "xfa/fwl/core/fwl_noteimp.h"
 #include "xfa/fxfa/app/xfa_ffnotify.h"
 #include "xfa/fxfa/include/xfa_checksum.h"
 #include "xfa/fxfa/include/xfa_ffapp.h"
 #include "xfa/fxfa/include/xfa_ffdocview.h"
 #include "xfa/fxfa/include/xfa_ffwidget.h"
 #include "xfa/fxfa/include/xfa_fontmgr.h"
 #include "xfa/fxfa/parser/xfa_document.h"
 #include "xfa/fxfa/parser/xfa_document_serialize.h"
 #include "xfa/fxfa/parser/xfa_parser.h"
 #include "xfa/fxfa/parser/xfa_parser_imp.h"
 #include "xfa/fxfa/parser/xfa_parser_imp.h"
 
+namespace {
+
+struct FX_BASE64DATA {

[dsinclair, 2016/05/18 21:15:35]

This struct is duplicated, but given what it contains/does I thought that was
acceptable.

[Tom Sepez, 2016/05/18 22:01:21]

Acknowledged.

+  uint32_t data1 : 2;
+  uint32_t data2 : 6;
+  uint32_t data3 : 4;
+  uint32_t data4 : 4;
+  uint32_t data5 : 6;
+  uint32_t data6 : 2;
+  uint32_t data7 : 8;
+};
+
+const uint8_t g_FXBase64DecoderMap[256] = {
+    0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
+    0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
+    0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
+    0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x3E, 0xFF, 0xFF, 0xFF, 0x3F,
+    0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3A, 0x3B, 0x3C, 0x3D, 0xFF, 0xFF,
+    0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06,
+    0x07, 0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F, 0x10, 0x11, 0x12,
+    0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
+    0xFF, 0x1A, 0x1B, 0x1C, 0x1D, 0x1E, 0x1F, 0x20, 0x21, 0x22, 0x23, 0x24,
+    0x25, 0x26, 0x27, 0x28, 0x29, 0x2A, 0x2B, 0x2C, 0x2D, 0x2E, 0x2F, 0x30,
+    0x31, 0x32, 0x33, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
+    0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
+    0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,

[Tom Sepez, 2016/05/18 22:01:21]

Again, we could probably save 128 bytes here.

[dsinclair, 2016/05/19 14:24:44]

Done.

Please check my numbers are right.

+    0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
+    0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
+    0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
+    0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
+    0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
+    0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
+    0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
+    0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
+    0xFF, 0xFF, 0xFF, 0xFF,
+};
+
+void Base64DecodePiece(const FX_CHAR src[4],
+                       int32_t iChars,
+                       FX_BASE64DATA& dst,
+                       int32_t& iBytes) {
+  ASSERT(iChars > 0 && iChars < 5);
+  iBytes = 1;
+  dst.data2 = g_FXBase64DecoderMap[(uint8_t)src[0]];
+  if (iChars > 1) {
+    uint8_t b = g_FXBase64DecoderMap[(uint8_t)src[1]];
+    dst.data1 = b >> 4;
+    dst.data4 = b;
+    if (iChars > 2) {
+      iBytes = 2;
+      b = g_FXBase64DecoderMap[(uint8_t)src[2]];
+      dst.data3 = b >> 2;
+      dst.data6 = b;
+      if (iChars > 3) {
+        iBytes = 3;
+        dst.data5 = g_FXBase64DecoderMap[(uint8_t)src[3]];
+      } else {
+        dst.data5 = 0;
+      }
+    } else {
+      dst.data3 = 0;
+    }
+  } else {
+    dst.data1 = 0;
+  }
+}
+
+int32_t Base64DecodeW(const FX_WCHAR* pSrc, int32_t iSrcLen, uint8_t* pDst) {
+  ASSERT(pSrc != NULL);
+  if (iSrcLen < 1) {
+    return 0;
+  }
+  while (iSrcLen > 0 && pSrc[iSrcLen - 1] == '=') {
+    iSrcLen--;
+  }
+  if (iSrcLen < 1) {
+    return 0;
+  }
+  if (pDst == NULL) {
+    int32_t iDstLen = iSrcLen / 4 * 3;
+    iSrcLen %= 4;
+    if (iSrcLen == 1) {
+      iDstLen += 1;
+    } else if (iSrcLen == 2) {
+      iDstLen += 1;
+    } else if (iSrcLen == 3) {
+      iDstLen += 2;
+    }
+    return iDstLen;
+  }
+  FX_CHAR srcData[4];
+  FX_BASE64DATA dstData;
+  int32_t iChars = 4, iBytes;
+  uint8_t* pDstEnd = pDst;
+  while (iSrcLen > 0) {
+    if (iSrcLen > 3) {
+      srcData[0] = (FX_CHAR)*pSrc++;
+      srcData[1] = (FX_CHAR)*pSrc++;
+      srcData[2] = (FX_CHAR)*pSrc++;
+      srcData[3] = (FX_CHAR)*pSrc++;
+      iSrcLen -= 4;
+    } else {
+      *((uint32_t*)&dstData) = 0;
+      *((uint32_t*)srcData) = 0;
+      srcData[0] = (FX_CHAR)*pSrc++;
+      if (iSrcLen > 1) {
+        srcData[1] = (FX_CHAR)*pSrc++;
+      }
+      if (iSrcLen > 2) {
+        srcData[2] = (FX_CHAR)*pSrc++;
+      }
+      iChars = iSrcLen;
+      iSrcLen = 0;
+    }
+    Base64DecodePiece(srcData, iChars, dstData, iBytes);
+    *pDstEnd++ = ((uint8_t*)&dstData)[0];
+    if (iBytes > 1) {
+      *pDstEnd++ = ((uint8_t*)&dstData)[1];
+    }
+    if (iBytes > 2) {
+      *pDstEnd++ = ((uint8_t*)&dstData)[2];
+    }
+  }
+  return pDstEnd - pDst;
+}
+
+}  // namespace
+
 CXFA_FFDoc::CXFA_FFDoc(CXFA_FFApp* pApp, IXFA_DocProvider* pDocProvider)
     : m_pDocProvider(pDocProvider),
       m_pDocument(nullptr),
       m_pStream(nullptr),
       m_pApp(pApp),
       m_pNotify(nullptr),
       m_pPDFDoc(nullptr),
       m_dwDocType(XFA_DOCTYPE_Static),
       m_bOwnStream(TRUE) {}
 CXFA_FFDoc::~CXFA_FFDoc() {
@@ skipping 42 matching lines @@
         break;
       }
     }
   }
   if (!pChunkElement) {
     return FALSE;
   }
   CFX_WideString wsPDFContent;
   pChunkElement->GetTextData(wsPDFContent);
   iBufferSize =
-      FX_Base64DecodeW(wsPDFContent.c_str(), wsPDFContent.GetLength(), NULL);
+      Base64DecodeW(wsPDFContent.c_str(), wsPDFContent.GetLength(), NULL);

[Tom Sepez, 2016/05/18 22:01:21]

nit: nullptr

[dsinclair, 2016/05/19 14:24:44]

Done.

   pByteBuffer = FX_Alloc(uint8_t, iBufferSize + 1);
   pByteBuffer[iBufferSize] = '0';  // FIXME: I bet this is wrong.
-  FX_Base64DecodeW(wsPDFContent.c_str(), wsPDFContent.GetLength(), pByteBuffer);
+  Base64DecodeW(wsPDFContent.c_str(), wsPDFContent.GetLength(), pByteBuffer);
   return TRUE;
 }
 void XFA_XPDPacket_MergeRootNode(CXFA_Node* pOriginRoot, CXFA_Node* pNewRoot) {
   CXFA_Node* pChildNode = pNewRoot->GetNodeItem(XFA_NODEITEM_FirstChild);
   while (pChildNode) {
     CXFA_Node* pOriginChild =
         pOriginRoot->GetFirstChildByName(pChildNode->GetNameHash());
     if (pOriginChild) {
       pChildNode = pChildNode->GetNodeItem(XFA_NODEITEM_NextSibling);
     } else {
@@ skipping 274 matching lines @@
 
   return pExport->Export(pFile, pNode, 0,
                          bsChecksum.GetLength() ? bsChecksum.c_str() : nullptr);
 }
 
 FX_BOOL CXFA_FFDoc::ImportData(IFX_FileRead* pStream, FX_BOOL bXDP) {
   std::unique_ptr<CXFA_DataImporter> importer(
       new CXFA_DataImporter(m_pDocument));
   return importer->ImportData(pStream);
 }