courgette/simple_delta.cc

   1 // Copyright (c) 2010 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 // Implementation of the byte-level differential compression used internally by
   6 // Courgette.
   7
   8 #include "courgette/simple_delta.h"
   9
  10 #include "base/basictypes.h"
  11 #include "base/logging.h"
  12
  13 #include "courgette/third_party/bsdiff.h"
  14
  15 namespace courgette {
  16
  17 namespace {
  18
  19 Status BSDiffStatusToStatus(BSDiffStatus status) {
  20   switch (status) {
  21     case OK: return C_OK;
  22     case CRC_ERROR: return C_BINARY_DIFF_CRC_ERROR;
  23     default: return C_GENERAL_ERROR;
  24   }
  25 }
  26
  27 }
  28
  29 Status ApplySimpleDelta(SourceStream* old, SourceStream* delta,
  30                         SinkStream* target) {
  31   return BSDiffStatusToStatus(ApplyBinaryPatch(old, delta, target));
  32 }
  33
  34 Status GenerateSimpleDelta(SourceStream* old, SourceStream* target,
  35                            SinkStream* delta) {
  36   VLOG(1) << "GenerateSimpleDelta " << old->Remaining()
  37           << " " << target->Remaining();
  38   return BSDiffStatusToStatus(CreateBinaryPatch(old, target, delta));
  39 }
  40
  41 }  // namespace courgette