content/browser/devtools/devtools_io_context.h

   1 // Copyright 2015 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 #include <map>
   6
   7 #include "base/callback.h"
   8 #include "base/files/file.h"
   9 #include "base/memory/ref_counted_delete_on_message_loop.h"
  10 #include "base/memory/ref_counted_memory.h"
  11
  12 namespace content {
  13 namespace devtools {
  14
  15 class DevToolsIOContext {
  16  public:
  17   class Stream : public base::RefCountedDeleteOnMessageLoop<Stream> {
  18    public:
  19     enum Status {
  20       StatusSuccess,
  21       StatusEOF,
  22       StatusFailure
  23     };
  24
  25     using ReadCallback = base::Callback<
  26         void(const scoped_refptr<base::RefCountedString>& data, int status)>;
  27
  28     void Read(off_t position, size_t max_size, ReadCallback callback);
  29     void Append(const scoped_refptr<base::RefCountedString>& data);
  30     const std::string& handle() const { return handle_; }
  31
  32    private:
  33     Stream();
  34     ~Stream();
  35     friend class DevToolsIOContext;
  36     friend class base::RefCountedDeleteOnMessageLoop<Stream>;
  37     friend class base::DeleteHelper<Stream>;
  38
  39     void ReadOnFileThread(off_t pos, size_t max_size, ReadCallback callback);
  40     void AppendOnFileThread(const scoped_refptr<base::RefCountedString>& data);
  41     bool InitOnFileThreadIfNeeded();
  42
  43     const std::string handle_;
  44     base::File file_;
  45     bool had_errors_;
  46     off_t last_read_pos_;
  47   };
  48
  49   DevToolsIOContext();
  50   ~DevToolsIOContext();
  51
  52   scoped_refptr<Stream> CreateTempFileBackedStream();
  53   scoped_refptr<Stream> GetByHandle(const std::string& handle);
  54   bool Close(const std::string& handle);
  55   void DiscardAllStreams();
  56
  57  private:
  58   using StreamsMap = std::map<std::string, scoped_refptr<Stream>>;
  59   StreamsMap streams_;
  60 };
  61
  62 }  // namespace devtools
  63 }  // namespace content