Unifying NativeMetafile class interface (as much as possible) for Linux, Mac, Win

printing/pdf_metafile_mac.cc

 // 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.
 
 #include "printing/pdf_metafile_mac.h"
 
 #include "base/file_path.h"
 #include "base/logging.h"
 #include "base/mac/scoped_cftyperef.h"
 #include "base/sys_string_conversions.h"
 #include "ui/gfx/rect.h"
+#include "ui/gfx/size.h"
 
 using base::mac::ScopedCFTypeRef;
 
 namespace printing {
 
 PdfMetafile::PdfMetafile()
     : page_is_open_(false) {
 }
 
 PdfMetafile::~PdfMetafile() {}
 
-CGContextRef PdfMetafile::Init() {
+bool PdfMetafile::Init() {
   // Ensure that Init hasn't already been called.
   DCHECK(!context_.get());
   DCHECK(!pdf_data_.get());
 
   pdf_data_.reset(CFDataCreateMutable(kCFAllocatorDefault, 0));
   if (!pdf_data_.get()) {
     LOG(ERROR) << "Failed to create pdf data for metafile";
-    return NULL;
+    return false;
   }
   ScopedCFTypeRef<CGDataConsumerRef> pdf_consumer(
       CGDataConsumerCreateWithCFData(pdf_data_));
   if (!pdf_consumer.get()) {
     LOG(ERROR) << "Failed to create data consumer for metafile";
     pdf_data_.reset(NULL);
-    return NULL;
+    return false;
   }
   context_.reset(CGPDFContextCreate(pdf_consumer, NULL, NULL));
   if (!context_.get()) {
     LOG(ERROR) << "Failed to create pdf context for metafile";
     pdf_data_.reset(NULL);
   }
 
-  return context_.get();
+  return true;
 }
 
 bool PdfMetafile::Init(const void* src_buffer, uint32 src_buffer_size) {
   DCHECK(!context_.get());
   DCHECK(!pdf_data_.get());
 
   if (!src_buffer || src_buffer_size == 0) {
     return false;
   }
 
   pdf_data_.reset(CFDataCreateMutable(kCFAllocatorDefault, src_buffer_size));
   CFDataAppendBytes(pdf_data_, static_cast<const UInt8*>(src_buffer),
                     src_buffer_size);
 
   return true;
 }
 
-CGContextRef PdfMetafile::StartPage(const gfx::Size& page_size,
-    const gfx::Point& content_origin, const float& scale_factor) {
-  DCHECK(context_.get());
-  DCHECK(!page_is_open_);
+uint32 PdfMetafile::GetDataSize() const {
+  // PDF data is only valid/complete once the context is released.
+  DCHECK(!context_);
 
-  double height = page_size.height();
-  double width = page_size.width();
-
-  CGRect bounds = CGRectMake(0, 0, width, height);
-  CGContextBeginPage(context_, &bounds);
-  page_is_open_ = true;
-  CGContextSaveGState(context_);
-
-  // Flip the context.
-  CGContextTranslateCTM(context_, 0, height);
-  CGContextScaleCTM(context_, scale_factor, -scale_factor);
-
-  // Move the context to origin.
-  CGContextTranslateCTM(context_, content_origin.x(), content_origin.y());
-
-  return context_.get();
+  if (!pdf_data_)
+    return 0;
+  return static_cast<uint32>(CFDataGetLength(pdf_data_));
 }
 
-void PdfMetafile::FinishPage() {
+bool PdfMetafile::GetData(void* dst_buffer, uint32 dst_buffer_size) const {
+  // PDF data is only valid/complete once the context is released.
+  DCHECK(!context_);
+  DCHECK(pdf_data_);
+  DCHECK(dst_buffer);
+  DCHECK_GT(dst_buffer_size, 0U);
+
+  uint32 data_size = GetDataSize();
+  if (dst_buffer_size > data_size) {
+    return false;
+  }
+
+  CFDataGetBytes(pdf_data_, CFRangeMake(0, dst_buffer_size),
+                 static_cast<UInt8*>(dst_buffer));
+  return true;
+}
+
+bool PdfMetafile::FinishPage() {
   DCHECK(context_.get());
   DCHECK(page_is_open_);
 
   CGContextRestoreGState(context_);
   CGContextEndPage(context_);
   page_is_open_ = false;
+  return true;
 }
 
 void PdfMetafile::Close() {
   DCHECK(context_.get());
   DCHECK(!page_is_open_);
 
 #ifndef NDEBUG
   // Check that the context will be torn down properly; if it's not, pdf_data_
   // will be incomplete and generate invalid PDF files/documents.
   if (context_.get()) {
     CFIndex extra_retain_count = CFGetRetainCount(context_.get()) - 1;
     if (extra_retain_count > 0) {
       LOG(ERROR) << "Metafile context has " << extra_retain_count
                  << " extra retain(s) on Close";
     }
   }
 #endif
   CGPDFContextClose(context_.get());
   context_.reset(NULL);
 }
 
+bool PdfMetafile::SaveTo(const FilePath& file_path) const {
+  DCHECK(pdf_data_.get());
+  DCHECK(!context_.get());
+
+  std::string path_string = file_path.value();
+  ScopedCFTypeRef<CFURLRef> path_url(CFURLCreateFromFileSystemRepresentation(
+      kCFAllocatorDefault, reinterpret_cast<const UInt8*>(path_string.c_str()),
+      path_string.length(), false));
+  SInt32 error_code;
+  CFURLWriteDataAndPropertiesToResource(path_url, pdf_data_, NULL, &error_code);
+  return error_code == 0;
+}
+
+gfx::Rect PdfMetafile::GetPageBounds(unsigned int page_number) const {
+  CGPDFDocumentRef pdf_doc = GetPDFDocument();
+  if (!pdf_doc) {
+    LOG(ERROR) << "Unable to create PDF document from data";
+    return gfx::Rect();
+  }
+  if (page_number > GetPageCount()) {
+    LOG(ERROR) << "Invalid page number: " << page_number;
+    return gfx::Rect();
+  }
+  CGPDFPageRef pdf_page = CGPDFDocumentGetPage(pdf_doc, page_number);
+  CGRect page_rect = CGPDFPageGetBoxRect(pdf_page, kCGPDFMediaBox);
+  return gfx::Rect(page_rect);
+}
+
+unsigned int PdfMetafile::GetPageCount() const {
+  CGPDFDocumentRef pdf_doc = GetPDFDocument();
+  return pdf_doc ? CGPDFDocumentGetNumberOfPages(pdf_doc) : 0;
+}
+
+CGContextRef PdfMetafile::StartPage(const gfx::Size& page_size,
+    const gfx::Point& content_origin, const float& scale_factor) {
+  DCHECK(context_.get());
+  DCHECK(!page_is_open_);
+
+  double height = page_size.height();
+  double width = page_size.width();
+
+  CGRect bounds = CGRectMake(0, 0, width, height);
+  CGContextBeginPage(context_, &bounds);
+  page_is_open_ = true;
+  CGContextSaveGState(context_);
+
+  // Flip the context.
+  CGContextTranslateCTM(context_, 0, height);
+  CGContextScaleCTM(context_, scale_factor, -scale_factor);
+
+  // Move the context to origin.
+  CGContextTranslateCTM(context_, content_origin.x(), content_origin.y());
+
+  return context_.get();
+}
+
 bool PdfMetafile::RenderPage(unsigned int page_number, CGContextRef context,
                              const CGRect rect, bool shrink_to_fit,
                              bool stretch_to_fit,
                              bool center_horizontally,
                              bool center_vertically) const {
   CGPDFDocumentRef pdf_doc = GetPDFDocument();
   if (!pdf_doc) {
     LOG(ERROR) << "Unable to create PDF document from data";
     return false;
   }
@@ skipping 32 matching lines @@
     y_offset += rect.size.height - (source_rect.size.height * scaling_factor);
   }
   CGContextSaveGState(context);
   CGContextTranslateCTM(context, x_offset, y_offset);
   CGContextScaleCTM(context, scaling_factor, scaling_factor);
   CGContextDrawPDFPage(context, pdf_page);
   CGContextRestoreGState(context);
   return true;
 }
 
-unsigned int PdfMetafile::GetPageCount() const {
-  CGPDFDocumentRef pdf_doc = GetPDFDocument();
-  return pdf_doc ? CGPDFDocumentGetNumberOfPages(pdf_doc) : 0;
-}
-
-gfx::Rect PdfMetafile::GetPageBounds(unsigned int page_number) const {
-  CGPDFDocumentRef pdf_doc = GetPDFDocument();
-  if (!pdf_doc) {
-    LOG(ERROR) << "Unable to create PDF document from data";
-    return gfx::Rect();
-  }
-  if (page_number > GetPageCount()) {
-    LOG(ERROR) << "Invalid page number: " << page_number;
-    return gfx::Rect();
-  }
-  CGPDFPageRef pdf_page = CGPDFDocumentGetPage(pdf_doc, page_number);
-  CGRect page_rect = CGPDFPageGetBoxRect(pdf_page, kCGPDFMediaBox);
-  return gfx::Rect(page_rect);
-}
-
-uint32 PdfMetafile::GetDataSize() const {
-  // PDF data is only valid/complete once the context is released.
-  DCHECK(!context_);
-
-  if (!pdf_data_)
-    return 0;
-  return static_cast<uint32>(CFDataGetLength(pdf_data_));
-}
-
-bool PdfMetafile::GetData(void* dst_buffer, uint32 dst_buffer_size) const {
-  // PDF data is only valid/complete once the context is released.
-  DCHECK(!context_);
-  DCHECK(pdf_data_);
-  DCHECK(dst_buffer);
-  DCHECK_GT(dst_buffer_size, 0U);
-
-  uint32 data_size = GetDataSize();
-  if (dst_buffer_size > data_size) {
-    return false;
-  }
-
-  CFDataGetBytes(pdf_data_, CFRangeMake(0, dst_buffer_size),
-                 static_cast<UInt8*>(dst_buffer));
-  return true;
-}
-
-bool PdfMetafile::SaveTo(const FilePath& file_path) const {
-  DCHECK(pdf_data_.get());
-  DCHECK(!context_.get());
-
-  std::string path_string = file_path.value();
-  ScopedCFTypeRef<CFURLRef> path_url(CFURLCreateFromFileSystemRepresentation(
-      kCFAllocatorDefault, reinterpret_cast<const UInt8*>(path_string.c_str()),
-      path_string.length(), false));
-  SInt32 error_code;
-  CFURLWriteDataAndPropertiesToResource(path_url, pdf_data_, NULL, &error_code);
-  return error_code == 0;
-}
-
 CGPDFDocumentRef PdfMetafile::GetPDFDocument() const {
   // Make sure that we have data, and that it's not being modified any more.
   DCHECK(pdf_data_.get());
   DCHECK(!context_.get());
 
   if (!pdf_doc_.get()) {
     ScopedCFTypeRef<CGDataProviderRef> pdf_data_provider(
         CGDataProviderCreateWithCFData(pdf_data_));
     pdf_doc_.reset(CGPDFDocumentCreateWithProvider(pdf_data_provider));
   }
   return pdf_doc_.get();
 }
 
 }  // namespace printing