printing/pdf_metafile_cg_mac.cc

   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 #include "printing/pdf_metafile_cg_mac.h"
   6
   7 #include <algorithm>
   8
   9 #include "base/files/file_path.h"
  10 #include "base/lazy_instance.h"
  11 #include "base/logging.h"
  12 #include "base/mac/mac_util.h"
  13 #include "base/mac/scoped_cftyperef.h"
  14 #include "base/strings/sys_string_conversions.h"
  15 #include "base/threading/thread_local.h"
  16 #include "ui/gfx/geometry/rect.h"
  17 #include "ui/gfx/geometry/size.h"
  18
  19 using base::ScopedCFTypeRef;
  20
  21 namespace {
  22
  23 // What is up with this ugly hack? <http://crbug.com/64641>, that's what.
  24 // The bug: Printing certain PDFs crashes. The cause: When printing, the
  25 // renderer process assembles pages one at a time, in PDF format, to send to the
  26 // browser process. When printing a PDF, the PDF plugin returns output in PDF
  27 // format. There is a bug in 10.5 and 10.6 (<rdar://9018916>,
  28 // <http://www.openradar.me/9018916>) where reference counting is broken when
  29 // drawing certain PDFs into PDF contexts. So at the high-level, a PdfMetafileCg
  30 // is used to hold the destination context, and then about five layers down on
  31 // the callstack, a PdfMetafileCg is used to hold the source PDF. If the source
  32 // PDF is drawn into the destination PDF context and then released, accessing
  33 // the destination PDF context will crash. So the outermost instantiation of
  34 // PdfMetafileCg creates a pool for deeper instantiations to dump their used
  35 // PDFs into rather than releasing them. When the top-level PDF is closed, then
  36 // it's safe to clear the pool. A thread local is used to allow this to work in
  37 // single-process mode. TODO(avi): This Apple bug appears fixed in 10.7; when
  38 // 10.7 is the minimum required version for Chromium, remove this hack.
  39
  40 base::LazyInstance<base::ThreadLocalPointer<struct __CFSet> >::Leaky
  41     thread_pdf_docs = LAZY_INSTANCE_INITIALIZER;
  42
  43 // Rotate a page by |num_rotations| * 90 degrees, counter-clockwise.
  44 void RotatePage(CGContextRef context, const CGRect rect, int num_rotations) {
  45   switch (num_rotations) {
  46     case 0:
  47       break;
  48     case 1:
  49       // After rotating by 90 degrees with the axis at the origin, the page
  50       // content is now "off screen". Shift it right to move it back on screen.
  51       CGContextTranslateCTM(context, rect.size.width, 0);
  52       // Rotates counter-clockwise by 90 degrees.
  53       CGContextRotateCTM(context, M_PI_2);
  54       break;
  55     case 2:
  56       // After rotating by 180 degrees with the axis at the origin, the page
  57       // content is now "off screen". Shift it right and up to move it back on
  58       // screen.
  59       CGContextTranslateCTM(context, rect.size.width, rect.size.height);
  60       // Rotates counter-clockwise by 90 degrees.
  61       CGContextRotateCTM(context, M_PI);
  62       break;
  63     case 3:
  64       // After rotating by 270 degrees with the axis at the origin, the page
  65       // content is now "off screen". Shift it right to move it back on screen.
  66       CGContextTranslateCTM(context, 0, rect.size.height);
  67       // Rotates counter-clockwise by 90 degrees.
  68       CGContextRotateCTM(context, -M_PI_2);
  69       break;
  70     default:
  71       NOTREACHED();
  72       break;
  73   };
  74 }
  75
  76 }  // namespace
  77
  78 namespace printing {
  79
  80 PdfMetafileCg::PdfMetafileCg()
  81     : page_is_open_(false),
  82       thread_pdf_docs_owned_(false) {
  83   if (!thread_pdf_docs.Pointer()->Get() &&
  84       base::mac::IsOSSnowLeopard()) {
  85     thread_pdf_docs_owned_ = true;
  86     thread_pdf_docs.Pointer()->Set(
  87         CFSetCreateMutable(kCFAllocatorDefault, 0, &kCFTypeSetCallBacks));
  88   }
  89 }
  90
  91 PdfMetafileCg::~PdfMetafileCg() {
  92   DCHECK(thread_checker_.CalledOnValidThread());
  93   if (pdf_doc_ && thread_pdf_docs.Pointer()->Get()) {
  94     // Transfer ownership to the pool.
  95     CFSetAddValue(thread_pdf_docs.Pointer()->Get(), pdf_doc_);
  96   }
  97
  98   if (thread_pdf_docs_owned_) {
  99     CFRelease(thread_pdf_docs.Pointer()->Get());
 100     thread_pdf_docs.Pointer()->Set(NULL);
 101   }
 102 }
 103
 104 bool PdfMetafileCg::Init() {
 105   // Ensure that Init hasn't already been called.
 106   DCHECK(!context_.get());
 107   DCHECK(!pdf_data_.get());
 108
 109   pdf_data_.reset(CFDataCreateMutable(kCFAllocatorDefault, 0));
 110   if (!pdf_data_.get()) {
 111     LOG(ERROR) << "Failed to create pdf data for metafile";
 112     return false;
 113   }
 114   ScopedCFTypeRef<CGDataConsumerRef> pdf_consumer(
 115       CGDataConsumerCreateWithCFData(pdf_data_));
 116   if (!pdf_consumer.get()) {
 117     LOG(ERROR) << "Failed to create data consumer for metafile";
 118     pdf_data_.reset(NULL);
 119     return false;
 120   }
 121   context_.reset(CGPDFContextCreate(pdf_consumer, NULL, NULL));
 122   if (!context_.get()) {
 123     LOG(ERROR) << "Failed to create pdf context for metafile";
 124     pdf_data_.reset(NULL);
 125   }
 126
 127   return true;
 128 }
 129
 130 bool PdfMetafileCg::InitFromData(const void* src_buffer,
 131                                  uint32 src_buffer_size) {
 132   DCHECK(!context_.get());
 133   DCHECK(!pdf_data_.get());
 134
 135   if (!src_buffer || src_buffer_size == 0) {
 136     return false;
 137   }
 138
 139   pdf_data_.reset(CFDataCreateMutable(kCFAllocatorDefault, src_buffer_size));
 140   CFDataAppendBytes(pdf_data_, static_cast<const UInt8*>(src_buffer),
 141                     src_buffer_size);
 142
 143   return true;
 144 }
 145
 146 bool PdfMetafileCg::StartPage(const gfx::Size& page_size,
 147                               const gfx::Rect& content_area,
 148                               const float& scale_factor) {
 149   DCHECK(context_.get());
 150   DCHECK(!page_is_open_);
 151
 152   double height = page_size.height();
 153   double width = page_size.width();
 154
 155   CGRect bounds = CGRectMake(0, 0, width, height);
 156   CGContextBeginPage(context_, &bounds);
 157   page_is_open_ = true;
 158   CGContextSaveGState(context_);
 159
 160   // Move to the context origin.
 161   CGContextTranslateCTM(context_, content_area.x(), -content_area.y());
 162
 163   // Flip the context.
 164   CGContextTranslateCTM(context_, 0, height);
 165   CGContextScaleCTM(context_, scale_factor, -scale_factor);
 166
 167   return context_.get() != NULL;
 168 }
 169
 170 bool PdfMetafileCg::FinishPage() {
 171   DCHECK(context_.get());
 172   DCHECK(page_is_open_);
 173
 174   CGContextRestoreGState(context_);
 175   CGContextEndPage(context_);
 176   page_is_open_ = false;
 177   return true;
 178 }
 179
 180 bool PdfMetafileCg::FinishDocument() {
 181   DCHECK(context_.get());
 182   DCHECK(!page_is_open_);
 183
 184 #ifndef NDEBUG
 185   // Check that the context will be torn down properly; if it's not, pdf_data_
 186   // will be incomplete and generate invalid PDF files/documents.
 187   if (context_.get()) {
 188     CFIndex extra_retain_count = CFGetRetainCount(context_.get()) - 1;
 189     if (extra_retain_count > 0) {
 190       LOG(ERROR) << "Metafile context has " << extra_retain_count
 191                  << " extra retain(s) on Close";
 192     }
 193   }
 194 #endif
 195   CGPDFContextClose(context_.get());
 196   context_.reset(NULL);
 197   return true;
 198 }
 199
 200 bool PdfMetafileCg::RenderPage(unsigned int page_number,
 201                                CGContextRef context,
 202                                const CGRect rect,
 203                                const MacRenderPageParams& params) const {
 204   CGPDFDocumentRef pdf_doc = GetPDFDocument();
 205   if (!pdf_doc) {
 206     LOG(ERROR) << "Unable to create PDF document from data";
 207     return false;
 208   }
 209   CGPDFPageRef pdf_page = CGPDFDocumentGetPage(pdf_doc, page_number);
 210   CGRect source_rect = CGPDFPageGetBoxRect(pdf_page, kCGPDFCropBox);
 211   int pdf_src_rotation = CGPDFPageGetRotationAngle(pdf_page);
 212   float scaling_factor = 1.0;
 213   const bool source_is_landscape =
 214         (source_rect.size.width > source_rect.size.height);
 215   const bool dest_is_landscape = (rect.size.width > rect.size.height);
 216   const bool rotate =
 217       params.autorotate ? (source_is_landscape != dest_is_landscape) : false;
 218   const float source_width =
 219       rotate ? source_rect.size.height : source_rect.size.width;
 220   const float source_height =
 221       rotate ? source_rect.size.width : source_rect.size.height;
 222
 223   // See if we need to scale the output.
 224   const bool scaling_needed =
 225       (params.shrink_to_fit && ((source_width > rect.size.width) ||
 226                                 (source_height > rect.size.height))) ||
 227       (params.stretch_to_fit && ((source_width < rect.size.width) &&
 228                                  (source_height < rect.size.height)));
 229   if (scaling_needed) {
 230     float x_scaling_factor = rect.size.width / source_width;
 231     float y_scaling_factor = rect.size.height / source_height;
 232     scaling_factor = std::min(x_scaling_factor, y_scaling_factor);
 233   }
 234   // Some PDFs have a non-zero origin. Need to take that into account and align
 235   // the PDF to the origin.
 236   const float x_origin_offset = -1 * source_rect.origin.x;
 237   const float y_origin_offset = -1 * source_rect.origin.y;
 238
 239   // If the PDF needs to be centered, calculate the offsets here.
 240   float x_offset = params.center_horizontally ?
 241       ((rect.size.width - (source_width * scaling_factor)) / 2) : 0;
 242   if (rotate)
 243     x_offset = -x_offset;
 244
 245   float y_offset = params.center_vertically ?
 246       ((rect.size.height - (source_height * scaling_factor)) / 2) : 0;
 247
 248   CGContextSaveGState(context);
 249
 250   // The transform operations specified here gets applied in reverse order.
 251   // i.e. the origin offset translation happens first.
 252   // Origin is at bottom-left.
 253   CGContextTranslateCTM(context, x_offset, y_offset);
 254
 255   int num_rotations = 0;
 256   if (rotate) {
 257     if (pdf_src_rotation == 0 || pdf_src_rotation == 270) {
 258       num_rotations = 1;
 259     } else {
 260       num_rotations = 3;
 261     }
 262   } else {
 263     if (pdf_src_rotation == 180 || pdf_src_rotation == 270) {
 264       num_rotations = 2;
 265     }
 266   }
 267   RotatePage(context, rect, num_rotations);
 268
 269   CGContextScaleCTM(context, scaling_factor, scaling_factor);
 270   CGContextTranslateCTM(context, x_origin_offset, y_origin_offset);
 271
 272   CGContextDrawPDFPage(context, pdf_page);
 273   CGContextRestoreGState(context);
 274
 275   return true;
 276 }
 277
 278 unsigned int PdfMetafileCg::GetPageCount() const {
 279   CGPDFDocumentRef pdf_doc = GetPDFDocument();
 280   return pdf_doc ? CGPDFDocumentGetNumberOfPages(pdf_doc) : 0;
 281 }
 282
 283 gfx::Rect PdfMetafileCg::GetPageBounds(unsigned int page_number) const {
 284   CGPDFDocumentRef pdf_doc = GetPDFDocument();
 285   if (!pdf_doc) {
 286     LOG(ERROR) << "Unable to create PDF document from data";
 287     return gfx::Rect();
 288   }
 289   if (page_number > GetPageCount()) {
 290     LOG(ERROR) << "Invalid page number: " << page_number;
 291     return gfx::Rect();
 292   }
 293   CGPDFPageRef pdf_page = CGPDFDocumentGetPage(pdf_doc, page_number);
 294   CGRect page_rect = CGPDFPageGetBoxRect(pdf_page, kCGPDFMediaBox);
 295   return gfx::Rect(page_rect);
 296 }
 297
 298 uint32 PdfMetafileCg::GetDataSize() const {
 299   // PDF data is only valid/complete once the context is released.
 300   DCHECK(!context_);
 301
 302   if (!pdf_data_)
 303     return 0;
 304   return static_cast<uint32>(CFDataGetLength(pdf_data_));
 305 }
 306
 307 bool PdfMetafileCg::GetData(void* dst_buffer, uint32 dst_buffer_size) const {
 308   // PDF data is only valid/complete once the context is released.
 309   DCHECK(!context_);
 310   DCHECK(pdf_data_);
 311   DCHECK(dst_buffer);
 312   DCHECK_GT(dst_buffer_size, 0U);
 313
 314   uint32 data_size = GetDataSize();
 315   if (dst_buffer_size > data_size) {
 316     return false;
 317   }
 318
 319   CFDataGetBytes(pdf_data_, CFRangeMake(0, dst_buffer_size),
 320                  static_cast<UInt8*>(dst_buffer));
 321   return true;
 322 }
 323
 324 CGContextRef PdfMetafileCg::context() const {
 325   return context_.get();
 326 }
 327
 328 CGPDFDocumentRef PdfMetafileCg::GetPDFDocument() const {
 329   // Make sure that we have data, and that it's not being modified any more.
 330   DCHECK(pdf_data_.get());
 331   DCHECK(!context_.get());
 332
 333   if (!pdf_doc_.get()) {
 334     ScopedCFTypeRef<CGDataProviderRef> pdf_data_provider(
 335         CGDataProviderCreateWithCFData(pdf_data_));
 336     pdf_doc_.reset(CGPDFDocumentCreateWithProvider(pdf_data_provider));
 337   }
 338   return pdf_doc_.get();
 339 }
 340
 341 }  // namespace printing