pdf/document_loader.h

   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 #ifndef PDF_DOCUMENT_LOADER_H_
   6 #define PDF_DOCUMENT_LOADER_H_
   7
   8 #include <list>
   9 #include <string>
  10 #include <vector>
  11
  12 #include "base/basictypes.h"
  13 #include "pdf/chunk_stream.h"
  14 #include "ppapi/cpp/url_loader.h"
  15 #include "ppapi/utility/completion_callback_factory.h"
  16
  17 #define kDefaultRequestSize 32768u
  18
  19 namespace chrome_pdf {
  20
  21 class DocumentLoader {
  22  public:
  23   class Client {
  24    public:
  25     virtual ~Client();
  26
  27     // Gets the pp::Instance object.
  28     virtual pp::Instance* GetPluginInstance() = 0;
  29     // Creates new URLLoader based on client settings.
  30     virtual pp::URLLoader CreateURLLoader() = 0;
  31     // Notification called when partial information about document is available.
  32     // Only called for urls that returns full content size and supports byte
  33     // range requests.
  34     virtual void OnPartialDocumentLoaded() = 0;
  35     // Notification called when all outstanding pending requests are complete.
  36     virtual void OnPendingRequestComplete() = 0;
  37     // Notification called when new data is available.
  38     virtual void OnNewDataAvailable() = 0;
  39     // Notification called when document is fully loaded.
  40     virtual void OnDocumentComplete() = 0;
  41   };
  42
  43   explicit DocumentLoader(Client* client);
  44   ~DocumentLoader();
  45
  46   bool Init(const pp::URLLoader& loader,
  47             const std::string& url,
  48             const std::string& headers);
  49
  50   // Data access interface. Return true is sucessful.
  51   bool GetBlock(uint32_t position, uint32_t size, void* buf) const;
  52
  53   // Data availability interface. Return true data avaialble.
  54   bool IsDataAvailable(uint32_t position, uint32_t size) const;
  55
  56   // Data availability interface. Return true data avaialble.
  57   void RequestData(uint32_t position, uint32_t size);
  58
  59   bool IsDocumentComplete() const;
  60   uint32_t document_size() const { return document_size_; }
  61
  62   // Return number of bytes available.
  63   uint32_t GetAvailableData() const;
  64
  65   // Clear pending requests from the queue.
  66   void ClearPendingRequests();
  67
  68   bool is_partial_document() const { return partial_document_; }
  69
  70  private:
  71   // Called by the completion callback of the document's URLLoader.
  72   void DidOpen(int32_t result);
  73   // Call to read data from the document's URLLoader.
  74   void ReadMore();
  75   // Called by the completion callback of the document's URLLoader.
  76   void DidRead(int32_t result);
  77
  78   // Called when we detect that partial document load is possible.
  79   void LoadPartialDocument();
  80   // Called when we have to load full document.
  81   void LoadFullDocument();
  82   // Download pending requests.
  83   void DownloadPendingRequests();
  84   // Called when we complete server request and read all data from it.
  85   void ReadComplete();
  86   // Creates request to download size byte of data data starting from position.
  87   pp::URLRequestInfo GetRequest(uint32_t position, uint32_t size) const;
  88   // Returns current request size in bytes.
  89   uint32_t GetRequestSize() const;
  90
  91   Client* client_;
  92   std::string url_;
  93   pp::URLLoader loader_;
  94   pp::CompletionCallbackFactory<DocumentLoader> loader_factory_;
  95   ChunkStream chunk_stream_;
  96   bool partial_document_;
  97   bool request_pending_;
  98   typedef std::list<std::pair<size_t, size_t> > PendingRequests;
  99   PendingRequests pending_requests_;
 100   char buffer_[kDefaultRequestSize];
 101   uint32_t current_pos_;
 102   uint32_t current_chunk_size_;
 103   uint32_t current_chunk_read_;
 104   uint32_t document_size_;
 105   bool header_request_;
 106   bool is_multipart_;
 107   std::string multipart_boundary_;
 108   uint32_t requests_count_;
 109   std::list<std::vector<unsigned char> > chunk_buffer_;
 110 };
 111
 112 }  // namespace chrome_pdf
 113
 114 #endif  // PDF_DOCUMENT_LOADER_H_