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// Copyright (c) 2009 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.
#ifndef PRINTING_PDF_PS_METAFILE_LINUX_H_
#define PRINTING_PDF_PS_METAFILE_LINUX_H_
#include <cairo.h>
#include <string>
#include "base/basictypes.h"
class FilePath;
namespace printing {
// This class uses Cairo graphics library to generate PostScript/PDF stream
// and stores rendering results in a string buffer.
class PdfPsMetafile {
public:
enum FileFormat {
PDF,
PS,
};
// The constructor we should use in the renderer process.
explicit PdfPsMetafile(const FileFormat& format);
// The constructor we should use in the browser process.
// |src_buffer| should point to the shared memory which stores PDF/PS
// contents generated in the renderer.
PdfPsMetafile(const FileFormat& format,
const void* src_buffer,
size_t src_buffer_size);
~PdfPsMetafile();
FileFormat GetFileFormat() { return format_; }
// Prepares a new cairo surface/context for rendering a new page.
bool StartPage(double width, double height); // The unit is pt (=1/72 in).
// Returns the Cairo context for rendering current page.
cairo_t* GetPageContext() const { return page_context_; }
// Destroys the surface and the context used in rendering current page.
// The results of current page will be appended into buffer |all_pages_|.
// TODO(myhuang): I plan to also do page setup here (margins, the header
// and the footer). At this moment, only pre-defined margins for US letter
// paper are hard-coded here.
// |shrink| decides the scaling factor to fit raw printing results into
// printable area.
void FinishPage(float shrink);
// Closes resulting PDF/PS file. No further rendering is allowed.
void Close();
// Returns size of PDF/PS contents stored in buffer |all_pages_|.
// This function should ONLY be called after PDF/PS file is closed.
unsigned int GetDataSize() const;
// Copies PDF/PS contents stored in buffer |all_pages_| into |dst_buffer|.
// This function should ONLY be called after PDF/PS file is closed.
void GetData(void* dst_buffer, size_t dst_buffer_size) const;
// Saves PDF/PS contents stored in buffer |all_pages_| into |filename| on
// the disk.
// This function should ONLY be called after PDF/PS file is closed.
bool SaveTo(const FilePath& filename) const;
private:
// Callback function for Cairo to write PDF/PS stream.
// |dst_buffer| is actually a pointer of type `std::string*`.
static cairo_status_t WriteCairoStream(void* dst_buffer,
const unsigned char* src_data,
unsigned int src_data_length);
// Convenient function to test if |surface| is valid.
bool IsSurfaceValid(cairo_surface_t* surface) const;
// Convenient function to test if |context| is valid.
bool IsContextValid(cairo_t* context) const;
FileFormat format_;
// Cairo surface and context for entire PDF/PS file.
cairo_surface_t* surface_;
cairo_t* context_;
// Cairo surface and context for current page only.
cairo_surface_t* page_surface_;
cairo_t* page_context_;
// Buffer stores PDF/PS contents for entire PDF/PS file.
std::string all_pages_;
// Buffer stores PDF/PS contents for current page only.
std::string current_page_;
DISALLOW_COPY_AND_ASSIGN(PdfPsMetafile);
};
} // namespace printing
#endif // PRINTING_PDF_PS_METAFILE_LINUX_H_
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