root/net/tools/dump_cache/simple_cache_dumper.cc

DEFINITIONS

1. rv_
2. Run
3. DoLoop
4. DoCreateCache
5. DoCreateCacheComplete
6. DoOpenEntry
7. DoOpenEntryComplete
8. DoCreateEntry
9. DoCreateEntryComplete
10. DoReadHeaders
11. DoReadHeadersComplete
12. DoWriteHeaders
13. DoWriteHeadersComplete
14. DoReadBody
15. DoReadBodyComplete
16. DoWriteBody
17. DoWriteBodyComplete
18. OnIOComplete

// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "net/tools/dump_cache/simple_cache_dumper.h"

#include "base/at_exit.h"
#include "base/command_line.h"
#include "base/logging.h"
#include "base/memory/scoped_ptr.h"
#include "base/message_loop/message_loop.h"
#include "base/message_loop/message_loop_proxy.h"
#include "base/threading/thread.h"
#include "net/base/cache_type.h"
#include "net/base/io_buffer.h"
#include "net/base/net_errors.h"
#include "net/disk_cache/disk_cache.h"
#include "net/tools/dump_cache/cache_dumper.h"

namespace net {

SimpleCacheDumper::SimpleCacheDumper(base::FilePath input_path,
                                     base::FilePath output_path)
    : state_(STATE_NONE),
      input_path_(input_path),
      output_path_(output_path),
      writer_(new DiskDumper(output_path)),
      cache_thread_(new base::Thread("CacheThead")),
      iter_(NULL),
      src_entry_(NULL),
      dst_entry_(NULL),
      io_callback_(base::Bind(&SimpleCacheDumper::OnIOComplete,
                              base::Unretained(this))),
      rv_(0) {
}

SimpleCacheDumper::~SimpleCacheDumper() {
}

int SimpleCacheDumper::Run() {
  base::MessageLoopForIO main_message_loop;

  LOG(INFO) << "Reading cache from: " << input_path_.value();
  LOG(INFO) << "Writing cache to: " << output_path_.value();

  if (!cache_thread_->StartWithOptions(
          base::Thread::Options(base::MessageLoop::TYPE_IO, 0))) {
    LOG(ERROR) << "Unable to start thread";
    return ERR_UNEXPECTED;
  }
  state_ = STATE_CREATE_CACHE;
  int rv = DoLoop(OK);
  if (rv == ERR_IO_PENDING) {
    main_message_loop.Run();
    return rv_;
  }
  return rv;
}

int SimpleCacheDumper::DoLoop(int rv) {
  do {
    State state = state_;
    state_ = STATE_NONE;
    switch (state) {
      case STATE_CREATE_CACHE:
        CHECK_EQ(OK, rv);
        rv = DoCreateCache();
        break;
      case STATE_CREATE_CACHE_COMPLETE:
        rv = DoCreateCacheComplete(rv);
        break;
      case STATE_OPEN_ENTRY:
        CHECK_EQ(OK, rv);
        rv = DoOpenEntry();
        break;
      case STATE_OPEN_ENTRY_COMPLETE:
        rv = DoOpenEntryComplete(rv);
        break;
      case STATE_CREATE_ENTRY:
        CHECK_EQ(OK, rv);
        rv = DoCreateEntry();
        break;
      case STATE_CREATE_ENTRY_COMPLETE:
        rv = DoCreateEntryComplete(rv);
        break;
      case STATE_READ_HEADERS:
        CHECK_EQ(OK, rv);
        rv = DoReadHeaders();
        break;
      case STATE_READ_HEADERS_COMPLETE:
        rv = DoReadHeadersComplete(rv);
        break;
      case STATE_WRITE_HEADERS:
        CHECK_EQ(OK, rv);
        rv = DoWriteHeaders();
        break;
      case STATE_WRITE_HEADERS_COMPLETE:
        rv = DoWriteHeadersComplete(rv);
        break;
      case STATE_READ_BODY:
        CHECK_EQ(OK, rv);
        rv = DoReadBody();
        break;
      case STATE_READ_BODY_COMPLETE:
        rv = DoReadBodyComplete(rv);
        break;
      case STATE_WRITE_BODY:
        CHECK_EQ(OK, rv);
        rv = DoWriteBody();
        break;
      case STATE_WRITE_BODY_COMPLETE:
        rv = DoWriteBodyComplete(rv);
        break;
      default:
        NOTREACHED() << "state_: " << state_;
        break;
    }
  } while (state_ != STATE_NONE && rv != ERR_IO_PENDING);
  return rv;
}

int SimpleCacheDumper::DoCreateCache() {
  DCHECK(!cache_);
  state_ = STATE_CREATE_CACHE_COMPLETE;
  return disk_cache::CreateCacheBackend(
      DISK_CACHE,
      CACHE_BACKEND_DEFAULT,
      input_path_,
      0,
      false,
      cache_thread_->message_loop_proxy().get(),
      NULL,
      &cache_,
      io_callback_);
}

int SimpleCacheDumper::DoCreateCacheComplete(int rv) {
  if (rv < 0)
    return rv;

  reinterpret_cast<disk_cache::BackendImpl*>(cache_.get())->SetUpgradeMode();
  reinterpret_cast<disk_cache::BackendImpl*>(cache_.get())->SetFlags(
      disk_cache::kNoRandom);

  state_ = STATE_OPEN_ENTRY;
  return OK;
}

int SimpleCacheDumper::DoOpenEntry() {
  DCHECK(!dst_entry_);
  DCHECK(!src_entry_);
  state_ = STATE_OPEN_ENTRY_COMPLETE;
  return cache_->OpenNextEntry(&iter_, &src_entry_, io_callback_);
}

int SimpleCacheDumper::DoOpenEntryComplete(int rv) {
  // ERR_FAILED indicates iteration finished.
  if (rv == ERR_FAILED) {
    cache_->EndEnumeration(&iter_);
    return OK;
  }

  if (rv < 0)
    return rv;

  state_ = STATE_CREATE_ENTRY;
  return OK;
}

int SimpleCacheDumper::DoCreateEntry() {
  DCHECK(!dst_entry_);
  state_ = STATE_CREATE_ENTRY_COMPLETE;

  return writer_->CreateEntry(src_entry_->GetKey(), &dst_entry_,
                              io_callback_);
}

int SimpleCacheDumper::DoCreateEntryComplete(int rv) {
  if (rv < 0)
    return rv;

  state_ = STATE_READ_HEADERS;
  return OK;
}

int SimpleCacheDumper::DoReadHeaders() {
  state_ = STATE_READ_HEADERS_COMPLETE;
  int32 size = src_entry_->GetDataSize(0);
  buf_ = new IOBufferWithSize(size);
  return src_entry_->ReadData(0, 0, buf_.get(), size, io_callback_);
}

int SimpleCacheDumper::DoReadHeadersComplete(int rv) {
  if (rv < 0)
    return rv;

  state_ = STATE_WRITE_HEADERS;
  return OK;
}

int SimpleCacheDumper::DoWriteHeaders() {
  int rv = writer_->WriteEntry(
      dst_entry_, 0, 0, buf_.get(), buf_->size(), io_callback_);
  if (rv == 0)
    return ERR_FAILED;

  state_ = STATE_WRITE_HEADERS_COMPLETE;
  return OK;
}

int SimpleCacheDumper::DoWriteHeadersComplete(int rv) {
  if (rv < 0)
    return rv;

  state_ = STATE_READ_BODY;
  return OK;
}

int SimpleCacheDumper::DoReadBody() {
  state_ = STATE_READ_BODY_COMPLETE;
  int32 size = src_entry_->GetDataSize(1);
  // If the body is empty, we can neither read nor write it, so
  // just move to the next.
  if (size <= 0) {
    state_ = STATE_WRITE_BODY_COMPLETE;
    return OK;
  }
  buf_ = new IOBufferWithSize(size);
  return src_entry_->ReadData(1, 0, buf_.get(), size, io_callback_);
}

int SimpleCacheDumper::DoReadBodyComplete(int rv) {
  if (rv < 0)
    return rv;

  state_ = STATE_WRITE_BODY;
  return OK;
}

int SimpleCacheDumper::DoWriteBody() {
  int rv = writer_->WriteEntry(
      dst_entry_, 1, 0, buf_.get(), buf_->size(), io_callback_);
  if (rv == 0)
    return ERR_FAILED;

  state_ = STATE_WRITE_BODY_COMPLETE;
  return OK;
}

int SimpleCacheDumper::DoWriteBodyComplete(int rv) {
  if (rv < 0)
    return rv;

  src_entry_->Close();
  writer_->CloseEntry(dst_entry_, base::Time::Now(), base::Time::Now());
  src_entry_ = NULL;
  dst_entry_ = NULL;

  state_ = STATE_OPEN_ENTRY;
  return OK;
}

void SimpleCacheDumper::OnIOComplete(int rv) {
  rv = DoLoop(rv);

  if (rv != ERR_IO_PENDING) {
    rv_ = rv;
    cache_.reset();
    base::MessageLoop::current()->Quit();
  }
}

}  // namespace net