Home | History | Annotate | Download | only in printing
      1 // Copyright (c) 2012 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 PRINTING_PRINTED_DOCUMENT_H_
      6 #define PRINTING_PRINTED_DOCUMENT_H_
      7 
      8 #include <map>
      9 
     10 #include "base/memory/ref_counted.h"
     11 #include "base/strings/string16.h"
     12 #include "base/synchronization/lock.h"
     13 #include "printing/print_settings.h"
     14 #include "ui/gfx/native_widget_types.h"
     15 
     16 namespace base {
     17 class FilePath;
     18 class MessageLoop;
     19 }
     20 
     21 namespace printing {
     22 
     23 class Metafile;
     24 class PrintedPage;
     25 class PrintedPagesSource;
     26 class PrintingContext;
     27 
     28 // A collection of rendered pages. The settings are immutable. If the print
     29 // settings are changed, a new PrintedDocument must be created.
     30 // Warning: May be accessed from many threads at the same time. Only one thread
     31 // will have write access. Sensible functions are protected by a lock.
     32 // Warning: Once a page is loaded, it cannot be replaced. Pages may be discarded
     33 // under low memory conditions.
     34 class PRINTING_EXPORT PrintedDocument
     35     : public base::RefCountedThreadSafe<PrintedDocument> {
     36  public:
     37   // The cookie shall be unique and has a specific relationship with its
     38   // originating source and settings.
     39   PrintedDocument(const PrintSettings& settings,
     40                   PrintedPagesSource* source,
     41                   int cookie);
     42 
     43   // Sets a page's data. 0-based. Takes metafile ownership.
     44   // Note: locks for a short amount of time.
     45   void SetPage(int page_number, Metafile* metafile, double shrink,
     46                const gfx::Size& paper_size, const gfx::Rect& page_rect);
     47 
     48   // Retrieves a page. If the page is not available right now, it
     49   // requests to have this page be rendered and returns false.
     50   // Note: locks for a short amount of time.
     51   bool GetPage(int page_number, scoped_refptr<PrintedPage>* page);
     52 
     53   // Draws the page in the context.
     54   // Note: locks for a short amount of time in debug only.
     55 #if defined(OS_WIN) || defined(OS_MACOSX) && !defined(USE_AURA)
     56   void RenderPrintedPage(const PrintedPage& page,
     57                          gfx::NativeDrawingContext context) const;
     58 #elif defined(OS_POSIX)
     59   void RenderPrintedPage(const PrintedPage& page,
     60                          PrintingContext* context) const;
     61 #endif
     62 
     63   // Returns true if all the necessary pages for the settings are already
     64   // rendered.
     65   // Note: locks while parsing the whole tree.
     66   bool IsComplete() const;
     67 
     68   // Disconnects the PrintedPage source (PrintedPagesSource). It is done when
     69   // the source is being destroyed.
     70   void DisconnectSource();
     71 
     72   // Retrieves the current memory usage of the renderer pages.
     73   // Note: locks for a short amount of time.
     74   uint32 MemoryUsage() const;
     75 
     76   // Sets the number of pages in the document to be rendered. Can only be set
     77   // once.
     78   // Note: locks for a short amount of time.
     79   void set_page_count(int max_page);
     80 
     81   // Number of pages in the document. Used for headers/footers.
     82   // Note: locks for a short amount of time.
     83   int page_count() const;
     84 
     85   // Returns the number of expected pages to be rendered. It is a non-linear
     86   // series if settings().ranges is not empty. It is the same value as
     87   // document_page_count() otherwise.
     88   // Note: locks for a short amount of time.
     89   int expected_page_count() const;
     90 
     91   // Getters. All these items are immutable hence thread-safe.
     92   const PrintSettings& settings() const { return immutable_.settings_; }
     93   const base::string16& name() const { return immutable_.name_; }
     94   int cookie() const { return immutable_.cookie_; }
     95 
     96   // Sets a path where to dump printing output files for debugging. If never set
     97   // no files are generated.
     98   static void set_debug_dump_path(const base::FilePath& debug_dump_path);
     99 
    100   static const base::FilePath& debug_dump_path();
    101 
    102  private:
    103   friend class base::RefCountedThreadSafe<PrintedDocument>;
    104 
    105   virtual ~PrintedDocument();
    106 
    107   // Array of data for each print previewed page.
    108   typedef std::map<int, scoped_refptr<PrintedPage> > PrintedPages;
    109 
    110   // Contains all the mutable stuff. All this stuff MUST be accessed with the
    111   // lock held.
    112   struct Mutable {
    113     explicit Mutable(PrintedPagesSource* source);
    114     ~Mutable();
    115 
    116     // Source that generates the PrintedPage's (i.e. a TabContents). It will be
    117     // set back to NULL if the source is deleted before this object.
    118     PrintedPagesSource* source_;
    119 
    120     // Contains the pages' representation. This is a collection of PrintedPage.
    121     // Warning: Lock must be held when accessing this member.
    122     PrintedPages pages_;
    123 
    124     // Number of expected pages to be rendered.
    125     // Warning: Lock must be held when accessing this member.
    126     int expected_page_count_;
    127 
    128     // The total number of pages in the document.
    129     int page_count_;
    130 
    131 #if defined(OS_POSIX) && !defined(OS_MACOSX)
    132     // Page number of the first page.
    133     int first_page;
    134 #endif
    135   };
    136 
    137   // Contains all the immutable stuff. All this stuff can be accessed without
    138   // any lock held. This is because it can't be changed after the object's
    139   // construction.
    140   struct Immutable {
    141     Immutable(const PrintSettings& settings, PrintedPagesSource* source,
    142               int cookie);
    143     ~Immutable();
    144 
    145     // Print settings used to generate this document. Immutable.
    146     PrintSettings settings_;
    147 
    148     // Native thread for the render source.
    149     base::MessageLoop* source_message_loop_;
    150 
    151     // Document name. Immutable.
    152     base::string16 name_;
    153 
    154     // Cookie to uniquely identify this document. It is used to make sure that a
    155     // PrintedPage is correctly belonging to the PrintedDocument. Since
    156     // PrintedPage generation is completely asynchronous, it could be easy to
    157     // mess up and send the page to the wrong document. It can be viewed as a
    158     // simpler hash of PrintSettings since a new document is made each time the
    159     // print settings change.
    160     int cookie_;
    161   };
    162 
    163   void DebugDump(const PrintedPage& page);
    164 
    165   // All writable data member access must be guarded by this lock. Needs to be
    166   // mutable since it can be acquired from const member functions.
    167   mutable base::Lock lock_;
    168 
    169   // All the mutable members.
    170   Mutable mutable_;
    171 
    172   // All the immutable members.
    173   const Immutable immutable_;
    174 
    175   DISALLOW_COPY_AND_ASSIGN(PrintedDocument);
    176 };
    177 
    178 }  // namespace printing
    179 
    180 #endif  // PRINTING_PRINTED_DOCUMENT_H_
    181