Fix a leak in CJBig2_Context.

core/src/fxcodec/jbig2/JBig2_Context.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 <list>
 #include "JBig2_Context.h"
 
 // Implement a very small least recently used (LRU) cache. It is very
 // common for a JBIG2 dictionary to span multiple pages in a PDF file,
 // and we do not want to decode the same dictionary over and over
 // again. We key off of the memory location of the dictionary. The
 // list keeps track of the freshness of entries, with freshest ones
 // at the front. Even a tiny cache size like 2 makes a dramatic
 // difference for typical JBIG2 documents.
 const int kSymbolDictCacheMaxSize = 2;
 
 CJBig2_Context* CJBig2_Context::CreateContext(
     const uint8_t* pGlobalData,
     FX_DWORD dwGlobalLength,
     const uint8_t* pData,
     FX_DWORD dwLength,
-    int32_t nStreamType,
     std::list<CJBig2_CachePair>* pSymbolDictCache,
     IFX_Pause* pPause) {
   return new CJBig2_Context(pGlobalData, dwGlobalLength, pData, dwLength,
-                            nStreamType, pSymbolDictCache, pPause);
+                            pSymbolDictCache, pPause);
 }
 void CJBig2_Context::DestroyContext(CJBig2_Context* pContext) {
   delete pContext;
 }
 CJBig2_Context::CJBig2_Context(const uint8_t* pGlobalData,
                                FX_DWORD dwGlobalLength,
                                const uint8_t* pData,
                                FX_DWORD dwLength,
-                               int32_t nStreamType,
                                std::list<CJBig2_CachePair>* pSymbolDictCache,
                                IFX_Pause* pPause) {
   if (pGlobalData && (dwGlobalLength > 0)) {
-    m_pGlobalContext =
-        new CJBig2_Context(NULL, 0, pGlobalData, dwGlobalLength,
-                           JBIG2_EMBED_STREAM, pSymbolDictCache, pPause);
+    m_pGlobalContext = new CJBig2_Context(
+        nullptr, 0, pGlobalData, dwGlobalLength, pSymbolDictCache, pPause);
   } else {
-    m_pGlobalContext = NULL;
+    m_pGlobalContext = nullptr;
   }
+
   m_pStream = new CJBig2_BitStream(pData, dwLength);
-  m_nStreamType = nStreamType;
   m_nState = JBIG2_OUT_OF_PAGE;
   m_pPage = NULL;
   m_bBufSpecified = FALSE;
   m_pPause = pPause;
   m_nSegmentDecoded = 0;
   m_PauseStep = 10;
   m_pArithDecoder = NULL;
   m_pGRD = NULL;
   m_gbContext = NULL;
   m_dwOffset = 0;
@@ skipping 10 matching lines @@
   delete m_pGlobalContext;
   m_pGlobalContext = NULL;
   if (m_bBufSpecified) {
     delete m_pPage;
   }
   m_pPage = NULL;
   delete m_pStream;
   m_pStream = NULL;
 }
 
-int32_t CJBig2_Context::decodeFile(IFX_Pause* pPause) {
-  if (m_pStream->getByteLeft() < 8)
-    return JBIG2_ERROR_TOO_SHORT;
-
-  const uint8_t fileID[] = {0x97, 0x4A, 0x42, 0x32, 0x0D, 0x0A, 0x1A, 0x0A};
-  if (JBIG2_memcmp(m_pStream->getPointer(), fileID, 8) != 0)
-    return JBIG2_ERROR_FILE_FORMAT;
-
-  m_pStream->offset(8);
-
-  uint8_t cFlags;
-  if (m_pStream->read1Byte(&cFlags) != 0)
-    return JBIG2_ERROR_TOO_SHORT;
-
-  if (!(cFlags & 0x02)) {
-    FX_DWORD dwTemp;
-    if (m_pStream->readInteger(&dwTemp) != 0)
-      return JBIG2_ERROR_TOO_SHORT;
-
-    if (dwTemp > 0) {
-      m_PageInfoList.clear();
-      m_PageInfoList.resize(dwTemp);
-    }
-  }
-
-  if (cFlags & 0x01) {
-    m_nStreamType = JBIG2_SQUENTIAL_STREAM;
-    return decode_SquentialOrgnazation(pPause);
-  }
-
-  m_nStreamType = JBIG2_RANDOM_STREAM;
-  return decode_RandomOrgnazation_FirstPage(pPause);
-}
-
 int32_t CJBig2_Context::decode_SquentialOrgnazation(IFX_Pause* pPause) {
   int32_t nRet;
   if (m_pStream->getByteLeft() <= 0)
     return JBIG2_END_OF_FILE;
 
   while (m_pStream->getByteLeft() >= JBIG2_MIN_SEGMENT_SIZE) {
     if (!m_pSegment) {
       m_pSegment.reset(new CJBig2_Segment);
       nRet = parseSegmentHeader(m_pSegment.get());
       if (nRet != JBIG2_SUCCESS) {
@@ skipping 96 matching lines @@
     m_ProcessingStatus = FXCODEC_STATUS_DECODE_TOBECONTINUE;
     return nRet;
   }
   int ret = Continue(pPause);
   return ret;
 }
 int32_t CJBig2_Context::Continue(IFX_Pause* pPause) {
   m_ProcessingStatus = FXCODEC_STATUS_DECODE_READY;
   int32_t nRet;
   if (m_PauseStep <= 1) {
-    switch (m_nStreamType) {
-      case JBIG2_FILE_STREAM:
-        nRet = decodeFile(pPause);
-        break;
-      case JBIG2_SQUENTIAL_STREAM:
-        nRet = decode_SquentialOrgnazation(pPause);
-        break;
-      case JBIG2_RANDOM_STREAM:
-        if (m_bFirstPage) {
-          nRet = decode_RandomOrgnazation_FirstPage(pPause);
-        } else {
-          nRet = decode_RandomOrgnazation(pPause);
-        }
-        break;
-      case JBIG2_EMBED_STREAM:
-        nRet = decode_EmbedOrgnazation(pPause);
-        break;
-      default:
-        m_ProcessingStatus = FXCODEC_STATUS_ERROR;
-        return JBIG2_ERROR_STREAM_TYPE;
-    }
+    nRet = decode_EmbedOrgnazation(pPause);
   } else if (m_PauseStep == 2) {
     nRet = decode_SquentialOrgnazation(pPause);
   } else if (m_PauseStep == 3) {
     nRet = decode_RandomOrgnazation_FirstPage(pPause);
   } else if (m_PauseStep == 4) {
     nRet = decode_RandomOrgnazation(pPause);
   } else if (m_PauseStep == 5) {
     m_ProcessingStatus = FXCODEC_STATUS_DECODE_FINISH;
     return JBIG2_SUCCESS;
   }
   if (m_ProcessingStatus == FXCODEC_STATUS_DECODE_TOBECONTINUE) {
     return nRet;
   }
   m_PauseStep = 5;
   if (!m_bBufSpecified && nRet == JBIG2_SUCCESS) {
     m_ProcessingStatus = FXCODEC_STATUS_DECODE_FINISH;
     return JBIG2_SUCCESS;
   }
   if (nRet == JBIG2_SUCCESS) {
     m_ProcessingStatus = FXCODEC_STATUS_DECODE_FINISH;
   } else {
     m_ProcessingStatus = FXCODEC_STATUS_ERROR;
   }
   return nRet;
 }
-int32_t CJBig2_Context::getFirstPage(CJBig2_Image** image, IFX_Pause* pPause) {
-  int32_t nRet;
-  m_bFirstPage = TRUE;
-  m_PauseStep = 0;
-  if (m_pGlobalContext) {
-    nRet = m_pGlobalContext->decode_EmbedOrgnazation(pPause);
-    if (nRet != JBIG2_SUCCESS) {
-      return nRet;
-    }
-  }
-  m_bBufSpecified = FALSE;
-  return Continue(pPause);
-}
+
 CJBig2_Segment* CJBig2_Context::findSegmentByNumber(FX_DWORD dwNumber) {
   CJBig2_Segment* pSeg;
   if (m_pGlobalContext) {
     pSeg = m_pGlobalContext->findSegmentByNumber(dwNumber);
     if (pSeg) {
       return pSeg;
     }
   }
   for (size_t i = 0; i < m_SegmentList.size(); ++i) {
     pSeg = m_SegmentList.get(i);
@@ skipping 1328 matching lines @@
         SBSYMCODES[CURTEMP].code = CURCODE;
         CURCODE = CURCODE + 1;
       }
       CURTEMP = CURTEMP + 1;
     }
     CURLEN = CURLEN + 1;
   }
   FX_Free(LENCOUNT);
   FX_Free(FIRSTCODE);
 }