Merge PDFiumPrint's public PrintPages methods.

Split raster PDF creation into its own function. Also add a helper
function to consistently check for PDFs with no pages.

Change-Id: I693282460b4da0e80bd1c5f2c022372bb7d58bb1
Reviewed-on: https://chromium-review.googlesource.com/1238353
Commit-Queue: Lei Zhang <thestig@chromium.org>
Reviewed-by: Rebekah Potter <rbpotter@chromium.org>
Cr-Commit-Position: refs/heads/master@{#593623}

pdf/pdfium/pdfium_engine.cc

@@ -1151,8 +1151,8 @@ pp::Buffer_Dev PDFiumEngine::PrintPagesAsRasterPdf(
   g_last_instance_id = client_->GetPluginInstance()->pp_instance();
 #endif
 
-  return print_.PrintPagesAsRasterPdf(page_ranges, page_range_count,
-                                      print_settings, pdf_print_settings);
+  return print_.PrintPagesAsPdf(page_ranges, page_range_count, print_settings,
+                                pdf_print_settings, /*raster=*/true);
 }
 
 pp::Buffer_Dev PDFiumEngine::PrintPagesAsPdf(
@@ -1175,7 +1175,7 @@ pp::Buffer_Dev PDFiumEngine::PrintPagesAsPdf(
   }
 
   return print_.PrintPagesAsPdf(page_ranges, page_range_count, print_settings,
-                                pdf_print_settings);
+                                pdf_print_settings, /*raster=*/false);
 }
 
 void PDFiumEngine::KillFormFocus() {

pdf/pdfium/pdfium_print.cc

@@ -4,6 +4,7 @@
 
 #include "pdf/pdfium/pdfium_print.h"
 
+#include <algorithm>
 #include <string>
 #include <utility>
 
@@ -37,6 +38,11 @@ bool ShouldDoNup(int pages_per_sheet) {
   return pages_per_sheet > 1;
 }
 
+// Returns the valid, positive page count, or 0 on failure.
+int GetDocumentPageCount(FPDF_DOCUMENT doc) {
+  return std::max(FPDF_GetPageCount(doc), 0);
+}
+
 // Set the destination page size and content area in points based on source
 // page rotation and orientation.
 //
@@ -273,51 +279,19 @@ void PDFiumPrint::FitContentsToPrintableArea(FPDF_DOCUMENT doc,
   FitContentsToPrintableAreaIfRequired(doc, 1.0, print_settings);
 }
 
-pp::Buffer_Dev PDFiumPrint::PrintPagesAsRasterPdf(
-    const PP_PrintPageNumberRange_Dev* page_ranges,
-    uint32_t page_range_count,
-    const PP_PrintSettings_Dev& print_settings,
-    const PP_PdfPrintSettings_Dev& pdf_print_settings) {
-  ScopedFPDFDocument output_doc = CreatePrintPdf(
-      page_ranges, page_range_count, print_settings, pdf_print_settings);
-  if (!output_doc)
-    return pp::Buffer_Dev();
-
-  int page_count = FPDF_GetPageCount(output_doc.get());
-  if (page_count <= 0)
-    return pp::Buffer_Dev();
-
-  ScopedFPDFDocument rasterized_output_doc(FPDF_CreateNewDocument());
-  DCHECK(rasterized_output_doc);
-
-  for (int i = 0; i < page_count; ++i) {
-    ScopedFPDFPage pdf_page(FPDF_LoadPage(output_doc.get(), i));
-    if (!pdf_page)
-      return pp::Buffer_Dev();
-
-    ScopedFPDFDocument temp_doc =
-        CreateSinglePageRasterPdf(pdf_page.get(), print_settings);
-    if (!temp_doc)
-      return pp::Buffer_Dev();
-
-    if (!FPDF_ImportPages(rasterized_output_doc.get(), temp_doc.get(), "1", i))
-      return pp::Buffer_Dev();
-  }
-
-  FPDF_CopyViewerPreferences(rasterized_output_doc.get(), engine_->doc());
-  return GetPrintData(rasterized_output_doc.get());
-}
-
 pp::Buffer_Dev PDFiumPrint::PrintPagesAsPdf(
     const PP_PrintPageNumberRange_Dev* page_ranges,
     uint32_t page_range_count,
     const PP_PrintSettings_Dev& print_settings,
-    const PP_PdfPrintSettings_Dev& pdf_print_settings) {
+    const PP_PdfPrintSettings_Dev& pdf_print_settings,
+    bool raster) {
   pp::Buffer_Dev buffer;
   ScopedFPDFDocument output_doc = CreatePrintPdf(
       page_ranges, page_range_count, print_settings, pdf_print_settings);
-  if (output_doc)
-    buffer = GetPrintData(output_doc.get());
+  if (raster)
+    output_doc = CreateRasterPdf(std::move(output_doc), print_settings);
+  if (GetDocumentPageCount(output_doc.get()))
+    buffer = ConvertDocToBuffer(std::move(output_doc));
   return buffer;
 }
 
@@ -352,6 +326,34 @@ ScopedFPDFDocument PDFiumPrint::CreatePrintPdf(
   return output_doc;
 }
 
+ScopedFPDFDocument PDFiumPrint::CreateRasterPdf(
+    ScopedFPDFDocument doc,
+    const PP_PrintSettings_Dev& print_settings) {
+  int page_count = GetDocumentPageCount(doc.get());
+  if (page_count == 0)
+    return nullptr;
+
+  ScopedFPDFDocument rasterized_doc(FPDF_CreateNewDocument());
+  DCHECK(rasterized_doc);
+  FPDF_CopyViewerPreferences(rasterized_doc.get(), doc.get());
+
+  for (int i = 0; i < page_count; ++i) {
+    ScopedFPDFPage pdf_page(FPDF_LoadPage(doc.get(), i));
+    if (!pdf_page)
+      return nullptr;
+
+    ScopedFPDFDocument temp_doc =
+        CreateSinglePageRasterPdf(pdf_page.get(), print_settings);
+    if (!temp_doc)
+      return nullptr;
+
+    if (!FPDF_ImportPages(rasterized_doc.get(), temp_doc.get(), "1", i))
+      return nullptr;
+  }
+
+  return rasterized_doc;
+}
+
 ScopedFPDFDocument PDFiumPrint::CreateSinglePageRasterPdf(
     FPDF_PAGE page_to_print,
     const PP_PrintSettings_Dev& print_settings) {
@@ -448,12 +450,12 @@ bool PDFiumPrint::FlattenPrintData(FPDF_DOCUMENT doc) const {
   return true;
 }
 
-pp::Buffer_Dev PDFiumPrint::GetPrintData(FPDF_DOCUMENT doc) const {
+pp::Buffer_Dev PDFiumPrint::ConvertDocToBuffer(ScopedFPDFDocument doc) const {
   DCHECK(doc);
 
   pp::Buffer_Dev buffer;
   PDFiumMemBufferFileWrite output_file_write;
-  if (FPDF_SaveAsCopy(doc, &output_file_write, 0)) {
+  if (FPDF_SaveAsCopy(doc.get(), &output_file_write, 0)) {
     size_t size = output_file_write.size();
     buffer = pp::Buffer_Dev(engine_->GetPluginInstance(), size);
     if (!buffer.is_null())

pdf/pdfium/pdfium_print.h

@@ -47,16 +47,12 @@ class PDFiumPrint {
                                          const gfx::Size& page_size,
                                          const gfx::Rect& printable_area);
 
-  pp::Buffer_Dev PrintPagesAsRasterPdf(
-      const PP_PrintPageNumberRange_Dev* page_ranges,
-      uint32_t page_range_count,
-      const PP_PrintSettings_Dev& print_settings,
-      const PP_PdfPrintSettings_Dev& pdf_print_settings);
   pp::Buffer_Dev PrintPagesAsPdf(
       const PP_PrintPageNumberRange_Dev* page_ranges,
       uint32_t page_range_count,
       const PP_PrintSettings_Dev& print_settings,
-      const PP_PdfPrintSettings_Dev& pdf_print_settings);
+      const PP_PdfPrintSettings_Dev& pdf_print_settings,
+      bool raster);
 
  private:
   ScopedFPDFDocument CreatePrintPdf(
@@ -65,12 +61,16 @@ class PDFiumPrint {
       const PP_PrintSettings_Dev& print_settings,
       const PP_PdfPrintSettings_Dev& pdf_print_settings);
 
+  ScopedFPDFDocument CreateRasterPdf(
+      ScopedFPDFDocument doc,
+      const PP_PrintSettings_Dev& print_settings);
+
   ScopedFPDFDocument CreateSinglePageRasterPdf(
       FPDF_PAGE page_to_print,
       const PP_PrintSettings_Dev& print_settings);
 
   bool FlattenPrintData(FPDF_DOCUMENT doc) const;
-  pp::Buffer_Dev GetPrintData(FPDF_DOCUMENT doc) const;
+  pp::Buffer_Dev ConvertDocToBuffer(ScopedFPDFDocument doc) const;
 
   PDFiumEngine* const engine_;