PDF: Add some CHECKS to help debug a crash.

pdf/pdfium/pdfium_engine.cc

 // Copyright (c) 2012 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 "pdf/pdfium/pdfium_engine.h"
 
 #include <math.h>
 
 #include "base/json/json_writer.h"
 #include "base/logging.h"
@@ skipping 1946 matching lines @@
 
 std::string PDFiumEngine::GetPageAsJSON(int index) {
   if (!(HasPermission(PERMISSION_COPY) ||
         HasPermission(PERMISSION_COPY_ACCESSIBLE))) {
     return "{}";
   }
 
   if (index < 0 || static_cast<size_t>(index) > pages_.size() - 1)
     return "{}";
 
+  // TODO(thestig) Remove after debugging http://crbug.com/402035
+  CHECK(pages_[index]);
   scoped_ptr<base::Value> node(
       pages_[index]->GetAccessibleContentAsValue(current_rotation_));
   std::string page_json;
   base::JSONWriter::Write(node.get(), &page_json);
   return page_json;
 }
 
 bool PDFiumEngine::GetPrintScaling() {
   return !!FPDF_VIEWERREF_GetPrintScaling(doc_);
 }
@@ skipping 37 matching lines @@
   for (int i = 1; i < num_pages; ++i) {
     pp::Rect page_rect(page_rects[i]);
     page_rect.Inset(kPageShadowLeft, kPageShadowTop,
                     kPageShadowRight, kPageShadowBottom);
     double width_in_points =
         page_rect.width() * kPointsPerInch / kPixelsPerInch;
     double height_in_points =
         page_rect.height() * kPointsPerInch / kPixelsPerInch;
     FPDFPage_New(doc_, i, width_in_points, height_in_points);
     pages_.push_back(new PDFiumPage(this, i, page_rect, true));
+    // TODO(thestig) Remove after debugging http://crbug.com/402035
+    CHECK(pages_.back());
   }
 
   CalculateVisiblePages();
   if (document_size_ != old_document_size)
     client_->DocumentSizeUpdated(document_size_);
 }
 
 void PDFiumEngine::LoadDocument() {
   // Check if the document is ready for loading. If it isn't just bail for now,
   // we will call LoadDocument() again later.
@@ skipping 147 matching lines @@
   for (int i = 0; i < page_count; ++i) {
     // Center pages relative to the entire document.
     page_rects[i].set_x((document_size_.width() - page_rects[i].width()) / 2);
     pp::Rect page_rect(page_rects[i]);
     page_rect.Inset(kPageShadowLeft, kPageShadowTop,
                     kPageShadowRight, kPageShadowBottom);
     if (reload) {
       pages_[i]->set_rect(page_rect);
     } else {
       pages_.push_back(new PDFiumPage(this, i, page_rect, doc_complete));
+      // TODO(thestig) Remove after debugging http://crbug.com/402035
+      CHECK(pages_.back());
     }
   }
 
   CalculateVisiblePages();
   if (document_size_ != old_document_size)
     client_->DocumentSizeUpdated(document_size_);
 }
 
 void PDFiumEngine::CalculateVisiblePages() {
   // Clear pending requests queue, since it may contain requests to the pages
@@ skipping 1196 matching lines @@
     double* height) {
   FPDF_DOCUMENT doc = FPDF_LoadMemDocument(pdf_buffer, pdf_buffer_size, NULL);
   if (!doc)
     return false;
   bool success = FPDF_GetPageSizeByIndex(doc, page_number, width, height) != 0;
   FPDF_CloseDocument(doc);
   return success;
 }
 
 }  // namespace chrome_pdf