diff options
Diffstat (limited to 'lib/backupclient/BackupStoreFileRevDiff.cpp')
| -rw-r--r-- | lib/backupclient/BackupStoreFileRevDiff.cpp | 258 |
1 files changed, 0 insertions, 258 deletions
diff --git a/lib/backupclient/BackupStoreFileRevDiff.cpp b/lib/backupclient/BackupStoreFileRevDiff.cpp deleted file mode 100644 index 509eef61..00000000 --- a/lib/backupclient/BackupStoreFileRevDiff.cpp +++ /dev/null @@ -1,258 +0,0 @@ -// -------------------------------------------------------------------------- -// -// File -// Name: BackupStoreFileRevDiff.cpp -// Purpose: Reverse a patch, to build a new patch from new to old files -// Created: 12/7/04 -// -// -------------------------------------------------------------------------- - -#include "Box.h" - -#include <new> -#include <stdlib.h> - -#include "BackupStoreFile.h" -#include "BackupStoreFileWire.h" -#include "BackupStoreObjectMagic.h" -#include "BackupStoreException.h" -#include "BackupStoreConstants.h" -#include "BackupStoreFilename.h" - -#include "MemLeakFindOn.h" - - -// -------------------------------------------------------------------------- -// -// Function -// Name: BackupStoreFile::ReverseDiffFile(IOStream &, IOStream &, IOStream &, IOStream &, int64_t) -// Purpose: Reverse a patch, to build a new patch from new to old files. Takes -// two independent copies to the From file, for efficiency. -// Created: 12/7/04 -// -// -------------------------------------------------------------------------- -void BackupStoreFile::ReverseDiffFile(IOStream &rDiff, IOStream &rFrom, IOStream &rFrom2, IOStream &rOut, int64_t ObjectIDOfFrom, bool *pIsCompletelyDifferent) -{ - // Read and copy the header from the from file to the out file -- beginnings of the patch - file_StreamFormat hdr; - if(!rFrom.ReadFullBuffer(&hdr, sizeof(hdr), 0)) - { - THROW_EXCEPTION(BackupStoreException, FailedToReadBlockOnCombine) - } - if(ntohl(hdr.mMagicValue) != OBJECTMAGIC_FILE_MAGIC_VALUE_V1) - { - THROW_EXCEPTION(BackupStoreException, BadBackupStoreFile) - } - // Copy - rOut.Write(&hdr, sizeof(hdr)); - // Copy over filename and attributes - // BLOCK - { - BackupStoreFilename filename; - filename.ReadFromStream(rFrom, IOStream::TimeOutInfinite); - filename.WriteToStream(rOut); - StreamableMemBlock attr; - attr.ReadFromStream(rFrom, IOStream::TimeOutInfinite); - attr.WriteToStream(rOut); - } - - // Build an index of common blocks. - // For each block in the from file, we want to know it's index in the - // diff file. Allocate memory for this information. - int64_t fromNumBlocks = box_ntoh64(hdr.mNumBlocks); - int64_t *pfromIndexInfo = (int64_t*)::malloc(fromNumBlocks * sizeof(int64_t)); - if(pfromIndexInfo == 0) - { - throw std::bad_alloc(); - } - - // Buffer data - void *buffer = 0; - int bufferSize = 0; - - // flag - bool isCompletelyDifferent = true; - - try - { - // Initialise the index to be all 0, ie not filled in yet - for(int64_t i = 0; i < fromNumBlocks; ++i) - { - pfromIndexInfo[i] = 0; - } - - // Within the from file, skip to the index - MoveStreamPositionToBlockIndex(rDiff); - - // Read in header of index - file_BlockIndexHeader diffIdxHdr; - if(!rDiff.ReadFullBuffer(&diffIdxHdr, sizeof(diffIdxHdr), 0)) - { - THROW_EXCEPTION(BackupStoreException, CouldntReadEntireStructureFromStream) - } - if(ntohl(diffIdxHdr.mMagicValue) != OBJECTMAGIC_FILE_BLOCKS_MAGIC_VALUE_V1) - { - THROW_EXCEPTION(BackupStoreException, BadBackupStoreFile) - } - - // And then read in each entry - int64_t diffNumBlocks = box_ntoh64(diffIdxHdr.mNumBlocks); - for(int64_t b = 0; b < diffNumBlocks; ++b) - { - file_BlockIndexEntry e; - if(!rDiff.ReadFullBuffer(&e, sizeof(e), 0)) - { - THROW_EXCEPTION(BackupStoreException, CouldntReadEntireStructureFromStream) - } - - // Where's the block? - int64_t blockEn = box_ntoh64(e.mEncodedSize); - if(blockEn > 0) - { - // Block is in the delta file, is ignored for now -- not relevant to rebuilding the from file - } - else - { - // Block is in the original file, store which block it is in this file - int64_t fromIndex = 0 - blockEn; - if(fromIndex < 0 || fromIndex >= fromNumBlocks) - { - THROW_EXCEPTION(BackupStoreException, IncompatibleFromAndDiffFiles) - } - - // Store information about where it is in the new file - // NOTE: This is slight different to how it'll be stored in the final index. - pfromIndexInfo[fromIndex] = -1 - b; - } - } - - // Open the index for the second copy of the from file - MoveStreamPositionToBlockIndex(rFrom2); - - // Read in header of index - file_BlockIndexHeader fromIdxHdr; - if(!rFrom2.ReadFullBuffer(&fromIdxHdr, sizeof(fromIdxHdr), 0)) - { - THROW_EXCEPTION(BackupStoreException, CouldntReadEntireStructureFromStream) - } - if(ntohl(fromIdxHdr.mMagicValue) != OBJECTMAGIC_FILE_BLOCKS_MAGIC_VALUE_V1 - || box_ntoh64(fromIdxHdr.mOtherFileID) != 0) - { - THROW_EXCEPTION(BackupStoreException, BadBackupStoreFile) - } - - // So, we can now start building the data in the file - int64_t filePosition = rFrom.GetPosition(); - for(int64_t b = 0; b < fromNumBlocks; ++b) - { - // Read entry from from index - file_BlockIndexEntry e; - if(!rFrom2.ReadFullBuffer(&e, sizeof(e), 0)) - { - THROW_EXCEPTION(BackupStoreException, CouldntReadEntireStructureFromStream) - } - - // Get size - int64_t blockSize = box_hton64(e.mEncodedSize); - if(blockSize < 0) - { - THROW_EXCEPTION(BackupStoreException, BadBackupStoreFile) - } - - // Copy this block? - if(pfromIndexInfo[b] == 0) - { - // Copy it, first move to file location - rFrom.Seek(filePosition, IOStream::SeekType_Absolute); - - // Make sure there's memory available to copy this - if(bufferSize < blockSize || buffer == 0) - { - // Free old block - if(buffer != 0) - { - ::free(buffer); - buffer = 0; - bufferSize = 0; - } - // Allocate new block - buffer = ::malloc(blockSize); - if(buffer == 0) - { - throw std::bad_alloc(); - } - bufferSize = blockSize; - } - ASSERT(bufferSize >= blockSize); - - // Copy the block - if(!rFrom.ReadFullBuffer(buffer, blockSize, 0)) - { - THROW_EXCEPTION(BackupStoreException, FailedToReadBlockOnCombine) - } - rOut.Write(buffer, blockSize); - - // Store the size - pfromIndexInfo[b] = blockSize; - } - else - { - // Block isn't needed, so it's not completely different - isCompletelyDifferent = false; - } - filePosition += blockSize; - } - - // Then write the index, modified header first - fromIdxHdr.mOtherFileID = isCompletelyDifferent?0:(box_hton64(ObjectIDOfFrom)); - rOut.Write(&fromIdxHdr, sizeof(fromIdxHdr)); - - // Move to start of index entries - rFrom.Seek(filePosition + sizeof(file_BlockIndexHeader), IOStream::SeekType_Absolute); - - // Then copy modified entries - for(int64_t b = 0; b < fromNumBlocks; ++b) - { - // Read entry from from index - file_BlockIndexEntry e; - if(!rFrom.ReadFullBuffer(&e, sizeof(e), 0)) - { - THROW_EXCEPTION(BackupStoreException, CouldntReadEntireStructureFromStream) - } - - // Modify... - int64_t s = pfromIndexInfo[b]; - // Adjust to reflect real block index (remember 0 has a different meaning here) - if(s < 0) ++s; - // Insert - e.mEncodedSize = box_hton64(s); - // Write - rOut.Write(&e, sizeof(e)); - } - } - catch(...) - { - ::free(pfromIndexInfo); - if(buffer != 0) - { - ::free(buffer); - } - throw; - } - - // Free memory used (oh for finally {} blocks) - ::free(pfromIndexInfo); - if(buffer != 0) - { - ::free(buffer); - } - - // return completely different flag - if(pIsCompletelyDifferent != 0) - { - *pIsCompletelyDifferent = isCompletelyDifferent; - } -} - - - |