1 // Copyright 2012 The Chromium Authors
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
5 #ifndef PRINTING_METAFILE_H_
6 #define PRINTING_METAFILE_H_
12 #include "base/component_export.h"
13 #include "base/containers/span.h"
14 #include "base/memory/read_only_shared_memory_region.h"
15 #include "build/build_config.h"
16 #include "printing/mojom/print.mojom-forward.h"
17 #include "printing/native_drawing_context.h"
21 #elif BUILDFLAG(IS_MAC)
22 #include <ApplicationServices/ApplicationServices.h>
23 #include <CoreFoundation/CoreFoundation.h>
24 #include "base/mac/scoped_cftyperef.h"
38 // This class plays metafiles from data stream (usually PDF or EMF).
39 class COMPONENT_EXPORT(PRINTING_METAFILE) MetafilePlayer {
42 MetafilePlayer(const MetafilePlayer&) = delete;
43 MetafilePlayer& operator=(const MetafilePlayer&) = delete;
44 virtual ~MetafilePlayer();
47 // The slow version of Playback(). It enumerates all the records and play them
48 // back in the HDC. The trick is that it skip over the records known to have
49 // issue with some printers. See Emf::Record::SafePlayback implementation for
51 virtual bool SafePlayback(printing::NativeDrawingContext hdc) const = 0;
53 #elif BUILDFLAG(IS_MAC)
54 // Renders the given page into `rect` in the given context.
55 // Pages use a 1-based index. `autorotate` determines whether the source PDF
56 // should be autorotated to fit on the destination page. `fit_to_page`
57 // determines whether the source PDF should be scaled to fit on the
59 virtual bool RenderPage(unsigned int page_number,
60 printing::NativeDrawingContext context,
63 bool fit_to_page) const = 0;
64 #endif // BUILDFLAG(IS_WIN)
66 // Populates the buffer with the underlying data. This function should ONLY be
67 // called after the metafile is closed. Returns true if writing succeeded.
68 virtual bool GetDataAsVector(std::vector<char>* buffer) const = 0;
70 // Generates a read-only shared memory region for the underlying data. This
71 // function should ONLY be called after the metafile is closed. The returned
72 // region will be invalid if there is an error trying to generate the mapping.
73 virtual base::MappedReadOnlyRegion GetDataAsSharedMemoryRegion() const = 0;
75 // Determine if a copy of the data should be explicitly made before operating
76 // on metafile data. For security purposes it is important to not operate
77 // directly on the metafile data shared across processes, but instead work on
78 // a local copy made of such data. This query determines if such a copy needs
79 // to be made by the caller, since not all implementations are required to
80 // automatically do so.
81 // TODO(crbug.com/1135729) Eliminate concern about making a copy when the
82 // shared memory can't be written by the sender.
83 virtual bool ShouldCopySharedMemoryRegionData() const = 0;
85 // Identifies the type of encapsulated.
86 virtual mojom::MetafileDataType GetDataType() const = 0;
88 #if BUILDFLAG(IS_ANDROID)
89 // Similar to bool SaveTo(base::File* file) const, but write the data to the
90 // file descriptor directly. This is because Android doesn't allow file
91 // ownership exchange. This function should ONLY be called after the metafile
92 // is closed. Returns true if writing succeeded.
93 virtual bool SaveToFileDescriptor(int fd) const = 0;
95 // Saves the underlying data to the given file. This function should ONLY be
96 // called after the metafile is closed. Returns true if writing succeeded.
97 virtual bool SaveTo(base::File* file) const = 0;
98 #endif // BUILDFLAG(IS_ANDROID)
101 // This class creates a graphics context that renders into a data stream
102 // (usually PDF or EMF).
103 class COMPONENT_EXPORT(PRINTING_METAFILE) Metafile : public MetafilePlayer {
106 Metafile(const Metafile&) = delete;
107 Metafile& operator=(const Metafile&) = delete;
108 ~Metafile() override;
110 // Initializes a fresh new metafile for rendering. Returns false on failure.
111 // Note: It should only be called from within the renderer process to allocate
112 // rendering resources.
113 virtual bool Init() = 0;
115 // Initializes the metafile with `data`. Returns true on success.
116 // Note: It should only be called from within the browser process.
117 virtual bool InitFromData(base::span<const uint8_t> data) = 0;
119 // Prepares a context for rendering a new page with the given `page_size`,
120 // `content_area` and a `scale_factor` to use for the drawing. The units are
121 // in points (=1/72 in).
122 virtual void StartPage(const gfx::Size& page_size,
123 const gfx::Rect& content_area,
125 mojom::PageOrientation page_orientation) = 0;
127 // Closes the current page and destroys the context used in rendering that
128 // page. The results of current page will be appended into the underlying
129 // data stream. Returns true on success.
130 virtual bool FinishPage() = 0;
132 // Closes the metafile. No further rendering is allowed (the current page
133 // is implicitly closed).
134 virtual bool FinishDocument() = 0;
136 // Returns the size of the underlying data stream. Only valid after Close()
138 virtual uint32_t GetDataSize() const = 0;
140 // Copies the first `dst_buffer_size` bytes of the underlying data stream into
141 // `dst_buffer`. This function should ONLY be called after Close() is invoked.
142 // Returns true if the copy succeeds.
143 virtual bool GetData(void* dst_buffer, uint32_t dst_buffer_size) const = 0;
145 virtual gfx::Rect GetPageBounds(unsigned int page_number) const = 0;
146 virtual unsigned int GetPageCount() const = 0;
148 virtual printing::NativeDrawingContext context() const = 0;
150 #if BUILDFLAG(IS_WIN)
151 // "Plays" the EMF buffer in a HDC. It is the same effect as calling the
152 // original GDI function that were called when recording the EMF. `rect` is in
153 // "logical units" and is optional. If `rect` is NULL, the natural EMF bounds
155 // Note: Windows has been known to have stack buffer overflow in its GDI
156 // functions, whether used directly or indirectly through precompiled EMF
157 // data. We have to accept the risk here. Since it is used only for printing,
158 // it requires user intervention.
159 virtual bool Playback(printing::NativeDrawingContext hdc,
160 const RECT* rect) const = 0;
161 #endif // BUILDFLAG(IS_WIN)
163 // MetfilePlayer implementation.
164 bool GetDataAsVector(std::vector<char>* buffer) const override;
165 base::MappedReadOnlyRegion GetDataAsSharedMemoryRegion() const override;
166 #if !BUILDFLAG(IS_ANDROID)
167 bool SaveTo(base::File* file) const override;
168 #endif // !BUILDFLAG(IS_ANDROID)
171 } // namespace printing
173 #endif // PRINTING_METAFILE_H_