fgas/ code cleanup.

This CL shuffles code around in the fgas/ headers, removes unused functions
and adds anonymous namepaces for static methods and data.

Review-Url: https://codereview.chromium.org/1992033002

2 files changed, 225 insertions, 23 deletions

diff --git a/xfa/fxfa/app/xfa_checksum.cpp b/xfa/fxfa/app/xfa_checksum.cpp
index fab14c9b17..b5d9fdeb7d 100644
--- a/xfa/fxfa/app/xfa_checksum.cpp
+++ b/xfa/fxfa/app/xfa_checksum.cpp
@@ -7,7 +7,89 @@
 #include "xfa/fxfa/include/xfa_checksum.h"
 
 #include "core/fdrm/crypto/include/fx_crypt.h"
-#include "xfa/fgas/crt/fgas_algorithm.h"
+
+namespace {
+
+struct FX_BASE64DATA {
+  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 FX_CHAR g_FXBase64EncoderMap[64] = {
+    'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M',
+    'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z',
+    'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm',
+    'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z',
+    '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '+', '/',
+};
+
+void Base64EncodePiece(const FX_BASE64DATA& src,
+                       int32_t iBytes,
+                       FX_CHAR dst[4]) {
+  dst[0] = g_FXBase64EncoderMap[src.data2];
+  uint32_t b = src.data1 << 4;
+  if (iBytes > 1) {
+    b |= src.data4;
+  }
+  dst[1] = g_FXBase64EncoderMap[b];
+  if (iBytes > 1) {
+    b = src.data3 << 2;
+    if (iBytes > 2) {
+      b |= src.data6;
+    }
+    dst[2] = g_FXBase64EncoderMap[b];
+    if (iBytes > 2) {
+      dst[3] = g_FXBase64EncoderMap[src.data5];
+    } else {
+      dst[3] = '=';
+    }
+  } else {
+    dst[2] = dst[3] = '=';
+  }
+}
+
+int32_t Base64EncodeA(const uint8_t* pSrc, int32_t iSrcLen, FX_CHAR* pDst) {
+  ASSERT(pSrc != NULL);
+  if (iSrcLen < 1) {
+    return 0;
+  }
+  if (pDst == NULL) {
+    int32_t iDstLen = iSrcLen / 3 * 4;
+    if ((iSrcLen % 3) != 0) {
+      iDstLen += 4;
+    }
+    return iDstLen;
+  }
+  FX_BASE64DATA srcData;
+  int32_t iBytes = 3;
+  FX_CHAR* pDstEnd = pDst;
+  while (iSrcLen > 0) {
+    if (iSrcLen > 2) {
+      ((uint8_t*)&srcData)[0] = *pSrc++;
+      ((uint8_t*)&srcData)[1] = *pSrc++;
+      ((uint8_t*)&srcData)[2] = *pSrc++;
+      iSrcLen -= 3;
+    } else {
+      *((uint32_t*)&srcData) = 0;
+      ((uint8_t*)&srcData)[0] = *pSrc++;
+      if (iSrcLen > 1) {
+        ((uint8_t*)&srcData)[1] = *pSrc++;
+      }
+      iBytes = iSrcLen;
+      iSrcLen = 0;
+    }
+    Base64EncodePiece(srcData, iBytes, pDstEnd);
+    pDstEnd += 4;
+  }
+  return pDstEnd - pDst;
+}
+
+}  // namespace
 
 CXFA_SAXReaderHandler::CXFA_SAXReaderHandler(CXFA_ChecksumContext* pContext)
     : m_pContext(pContext) {
@@ -167,9 +249,9 @@ void CXFA_ChecksumContext::FinishChecksum() {
     uint8_t digest[20];
     FXSYS_memset(digest, 0, 20);
     CRYPT_SHA1Finish(m_pByteContext, digest);
-    int32_t nLen = FX_Base64EncodeA(digest, 20, NULL);
+    int32_t nLen = Base64EncodeA(digest, 20, NULL);
     FX_CHAR* pBuffer = m_bsChecksum.GetBuffer(nLen);
-    FX_Base64EncodeA(digest, 20, pBuffer);
+    Base64EncodeA(digest, 20, pBuffer);
     m_bsChecksum.ReleaseBuffer(nLen);
     FX_Free(m_pByteContext);
     m_pByteContext = NULL;
diff --git a/xfa/fxfa/app/xfa_ffdoc.cpp b/xfa/fxfa/app/xfa_ffdoc.cpp
index f93881564d..ce7628e43e 100644
--- a/xfa/fxfa/app/xfa_ffdoc.cpp
+++ b/xfa/fxfa/app/xfa_ffdoc.cpp
@@ -14,7 +14,6 @@
 #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"
@@ -28,6 +27,127 @@
 #include "xfa/fxfa/parser/xfa_parser_imp.h"
 #include "xfa/fxfa/parser/xfa_parser_imp.h"
 
+namespace {
+
+struct FX_BASE64DATA {
+  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 kStartValuesRemoved = 43;
+const uint8_t kDecoderMapSize = 80;
+const uint8_t g_FXBase64DecoderMap[kDecoderMapSize] = {
+    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,
+};
+
+uint8_t base64DecoderValue(uint8_t val) {
+  if (val < kStartValuesRemoved || val >= kStartValuesRemoved + kDecoderMapSize)
+    return 0xFF;
+  return g_FXBase64DecoderMap[val - kStartValuesRemoved];
+}
+
+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 = base64DecoderValue(static_cast<uint8_t>(src[0]));
+  if (iChars > 1) {
+    uint8_t b = base64DecoderValue(static_cast<uint8_t>(src[1]));
+    dst.data1 = b >> 4;
+    dst.data4 = b;
+    if (iChars > 2) {
+      iBytes = 2;
+      b = base64DecoderValue(static_cast<uint8_t>(src[2]));
+      dst.data3 = b >> 2;
+      dst.data6 = b;
+      if (iChars > 3) {
+        iBytes = 3;
+        dst.data5 = base64DecoderValue(static_cast<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);
+  if (iSrcLen < 1) {
+    return 0;
+  }
+  while (iSrcLen > 0 && pSrc[iSrcLen - 1] == '=') {
+    iSrcLen--;
+  }
+  if (iSrcLen < 1) {
+    return 0;
+  }
+  if (!pDst) {
+    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),
@@ -53,7 +173,7 @@ int32_t CXFA_FFDoc::StartLoad() {
 FX_BOOL XFA_GetPDFContentsFromPDFXML(CFDE_XMLNode* pPDFElement,
                                      uint8_t*& pByteBuffer,
                                      int32_t& iBufferSize) {
-  CFDE_XMLElement* pDocumentElement = NULL;
+  CFDE_XMLElement* pDocumentElement = nullptr;
   for (CFDE_XMLNode* pXMLNode =
            pPDFElement->GetNodeItem(CFDE_XMLNode::FirstChild);
        pXMLNode; pXMLNode = pXMLNode->GetNodeItem(CFDE_XMLNode::NextSibling)) {
@@ -70,7 +190,7 @@ FX_BOOL XFA_GetPDFContentsFromPDFXML(CFDE_XMLNode* pPDFElement,
   if (!pDocumentElement) {
     return FALSE;
   }
-  CFDE_XMLElement* pChunkElement = NULL;
+  CFDE_XMLElement* pChunkElement = nullptr;
   for (CFDE_XMLNode* pXMLNode =
            pDocumentElement->GetNodeItem(CFDE_XMLNode::FirstChild);
        pXMLNode; pXMLNode = pXMLNode->GetNodeItem(CFDE_XMLNode::NextSibling)) {
@@ -90,10 +210,10 @@ FX_BOOL XFA_GetPDFContentsFromPDFXML(CFDE_XMLNode* pPDFElement,
   CFX_WideString wsPDFContent;
   pChunkElement->GetTextData(wsPDFContent);
   iBufferSize =
-      FX_Base64DecodeW(wsPDFContent.c_str(), wsPDFContent.GetLength(), NULL);
+      Base64DecodeW(wsPDFContent.c_str(), wsPDFContent.GetLength(), nullptr);
   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) {
@@ -109,7 +229,7 @@ void XFA_XPDPacket_MergeRootNode(CXFA_Node* pOriginRoot, CXFA_Node* pNewRoot) {
       pNewRoot->RemoveChild(pChildNode);
       pOriginRoot->InsertChild(pChildNode);
       pChildNode = pNextSibling;
-      pNextSibling = NULL;
+      pNextSibling = nullptr;
     }
   }
 }
@@ -125,8 +245,8 @@ int32_t CXFA_FFDoc::DoLoad(IFX_Pause* pPause) {
       return XFA_PARSESTATUS_SyntaxErr;
     }
     int32_t iBufferSize = 0;
-    uint8_t* pByteBuffer = NULL;
-    IFX_FileRead* pXFAReader = NULL;
+    uint8_t* pByteBuffer = nullptr;
+    IFX_FileRead* pXFAReader = nullptr;
     if (XFA_GetPDFContentsFromPDFXML(pPDFXML, pByteBuffer, iBufferSize)) {
       pXFAReader = FX_CreateMemoryStream(pByteBuffer, iBufferSize, TRUE);
     } else {
@@ -149,9 +269,9 @@ int32_t CXFA_FFDoc::DoLoad(IFX_Pause* pPause) {
     if (!pParser) {
       return XFA_PARSESTATUS_SyntaxErr;
     }
-    CXFA_Node* pRootNode = NULL;
+    CXFA_Node* pRootNode = nullptr;
     if (pParser->StartParse(m_pStream) == XFA_PARSESTATUS_Ready &&
-        pParser->DoParse(NULL) == XFA_PARSESTATUS_Done) {
+        pParser->DoParse(nullptr) == XFA_PARSESTATUS_Done) {
       pRootNode = pParser->GetRootNode();
     }
     if (pRootNode && m_pDocument->GetRoot()) {
@@ -161,7 +281,7 @@ int32_t CXFA_FFDoc::DoLoad(IFX_Pause* pPause) {
       iStatus = XFA_PARSESTATUS_StatusErr;
     }
     pParser->Release();
-    pParser = NULL;
+    pParser = nullptr;
   }
   return iStatus;
 }
@@ -217,21 +337,21 @@ FX_BOOL CXFA_FFDoc::OpenDoc(IFX_FileRead* pStream, FX_BOOL bTakeOverFile) {
   return TRUE;
 }
 FX_BOOL CXFA_FFDoc::OpenDoc(CPDF_Document* pPDFDoc) {
-  if (pPDFDoc == NULL) {
+  if (!pPDFDoc)
     return FALSE;
-  }
+
   CPDF_Dictionary* pRoot = pPDFDoc->GetRoot();
-  if (pRoot == NULL) {
+  if (!pRoot)
     return FALSE;
-  }
+
   CPDF_Dictionary* pAcroForm = pRoot->GetDictBy("AcroForm");
-  if (pAcroForm == NULL) {
+  if (!pAcroForm)
     return FALSE;
-  }
+
   CPDF_Object* pElementXFA = pAcroForm->GetDirectObjectBy("XFA");
-  if (pElementXFA == NULL) {
+  if (!pElementXFA)
     return FALSE;
-  }
+
   CFX_ArrayTemplate<CPDF_Stream*> xfaStreams;
   if (pElementXFA->IsArray()) {
     CPDF_Array* pXFAArray = (CPDF_Array*)pElementXFA;
@@ -249,7 +369,7 @@ FX_BOOL CXFA_FFDoc::OpenDoc(CPDF_Document* pPDFDoc) {
   m_pPDFDoc = pPDFDoc;
   if (m_pStream) {
     m_pStream->Release();
-    m_pStream = NULL;
+    m_pStream = nullptr;
   }
   m_pStream = pFileRead;
   m_bOwnStream = TRUE;