Introduce ScopedFPDF types in public/cpp/fpdf_scopers.h

Applies std::remove_ptr to the public API types so that we can
deduce a correct unique ptr type no matter how that API might
change away from void* usage.

Creates shorter names for std::unique_ptr<std::remove_pointer<>, ...>

Change-Id: I04a0ff43cb7d5a4d3867939a53a54c9cef00db86
Reviewed-on: https://pdfium-review.googlesource.com/31292
Reviewed-by: Lei Zhang <thestig@chromium.org>
Reviewed-by: dsinclair <dsinclair@chromium.org>
Commit-Queue: Tom Sepez <tsepez@chromium.org>

3 files changed, 14 insertions, 20 deletions

diff --git a/samples/pdfium_test.cc b/samples/pdfium_test.cc
index 292673f1de..c2c217ddae 100644
--- a/samples/pdfium_test.cc
+++ b/samples/pdfium_test.cc
@@ -18,7 +18,7 @@
 #define _SKIA_SUPPORT_
 #endif
 
-#include "public/cpp/fpdf_deleters.h"
+#include "public/cpp/fpdf_scopers.h"
 #include "public/fpdf_annot.h"
 #include "public/fpdf_attachment.h"
 #include "public/fpdf_dataavail.h"
@@ -136,7 +136,7 @@ Optional<std::string> ExpandDirectoryPath(const std::string& path) {
 struct FPDF_FORMFILLINFO_PDFiumTest : public FPDF_FORMFILLINFO {
   // Hold a map of the currently loaded pages in order to avoid them
   // to get loaded twice.
-  std::map<int, std::unique_ptr<void, FPDFPageDeleter>> loaded_pages;
+  std::map<int, ScopedFPDFPage> loaded_pages;
 
   // Hold a pointer of FPDF_FORMHANDLE so that PDFium app hooks can
   // make use of it.
@@ -473,7 +473,7 @@ FPDF_PAGE GetPageForIndex(FPDF_FORMFILLINFO* param,
   if (iter != loaded_pages.end())
     return iter->second.get();
 
-  std::unique_ptr<void, FPDFPageDeleter> page(FPDF_LoadPage(doc, index));
+  ScopedFPDFPage page(FPDF_LoadPage(doc, index));
   if (!page)
     return nullptr;
 
@@ -513,8 +513,7 @@ bool RenderPage(const std::string& name,
     return true;
   }
 
-  std::unique_ptr<void, FPDFTextPageDeleter> text_page(FPDFText_LoadPage(page));
-
+  ScopedFPDFTextPage text_page(FPDFText_LoadPage(page));
   double scale = 1.0;
   if (!options.scale_factor_as_string.empty())
     std::stringstream(options.scale_factor_as_string) >> scale;
@@ -522,8 +521,7 @@ bool RenderPage(const std::string& name,
   auto width = static_cast<int>(FPDF_GetPageWidth(page) * scale);
   auto height = static_cast<int>(FPDF_GetPageHeight(page) * scale);
   int alpha = FPDFPage_HasTransparency(page) ? 1 : 0;
-  std::unique_ptr<void, FPDFBitmapDeleter> bitmap(
-      FPDFBitmap_Create(width, height, alpha));
+  ScopedFPDFBitmap bitmap(FPDFBitmap_Create(width, height, alpha));
 
   if (bitmap) {
     FPDF_DWORD fill_color = alpha ? 0x00000000 : 0xFFFFFFFF;
@@ -637,11 +635,10 @@ void RenderPdf(const std::string& name,
   hints.AddSegment = Add_Segment;
 
   // The pdf_avail must outlive doc.
-  std::unique_ptr<void, FPDFAvailDeleter> pdf_avail(
-      FPDFAvail_Create(&file_avail, &file_access));
+  ScopedFPDFAvail pdf_avail(FPDFAvail_Create(&file_avail, &file_access));
 
   // The document must outlive |form_callbacks.loaded_pages|.
-  std::unique_ptr<void, FPDFDocumentDeleter> doc;
+  ScopedFPDFDocument doc;
 
   int nRet = PDF_DATA_NOTAVAIL;
   bool bIsLinearized = false;
@@ -701,7 +698,7 @@ void RenderPdf(const std::string& name,
     form_callbacks.m_pJsPlatform = &platform_callbacks;
 #endif  // PDF_ENABLE_V8
 
-  std::unique_ptr<void, FPDFFormHandleDeleter> form(
+  ScopedFPDFFormHandle form(
       FPDFDOC_InitFormFillEnvironment(doc.get(), &form_callbacks));
   form_callbacks.form_handle = form.get();
 
diff --git a/samples/pdfium_test_dump_helper.cc b/samples/pdfium_test_dump_helper.cc
index 729a4cd152..2b422a93fb 100644
--- a/samples/pdfium_test_dump_helper.cc
+++ b/samples/pdfium_test_dump_helper.cc
@@ -11,7 +11,7 @@
 #include <string>
 #include <utility>
 
-#include "public/cpp/fpdf_deleters.h"
+#include "public/cpp/fpdf_scopers.h"
 #include "testing/test_support.h"
 
 namespace {
@@ -55,8 +55,7 @@ void DumpChildStructure(FPDF_STRUCTELEMENT child, int indent) {
 }
 
 void DumpPageStructure(FPDF_PAGE page, const int page_idx) {
-  std::unique_ptr<void, FPDFStructTreeDeleter> tree(
-      FPDF_StructTree_GetForPage(page));
+  ScopedFPDFStructTree tree(FPDF_StructTree_GetForPage(page));
   if (!tree) {
     fprintf(stderr, "Failed to load struct tree for page %d\n", page_idx);
     return;
diff --git a/samples/pdfium_test_write_helper.cc b/samples/pdfium_test_write_helper.cc
index d061252e07..c436c97fbe 100644
--- a/samples/pdfium_test_write_helper.cc
+++ b/samples/pdfium_test_write_helper.cc
@@ -9,7 +9,7 @@
 #include <memory>
 #include <vector>
 
-#include "public/cpp/fpdf_deleters.h"
+#include "public/cpp/fpdf_scopers.h"
 #include "public/fpdf_annot.h"
 #include "public/fpdf_attachment.h"
 #include "public/fpdf_edit.h"
@@ -215,7 +215,7 @@ void WriteText(FPDF_PAGE page, const char* pdf_name, int num) {
     return;
   }
 
-  std::unique_ptr<void, FPDFTextPageDeleter> textpage(FPDFText_LoadPage(page));
+  ScopedFPDFTextPage textpage(FPDFText_LoadPage(page));
   for (int i = 0; i < FPDFText_CountChars(textpage.get()); i++) {
     uint32_t c = FPDFText_GetUnicode(textpage.get(), i);
     if (fwrite(&c, sizeof(c), 1, fp) != 1) {
@@ -250,8 +250,7 @@ void WriteAnnot(FPDF_PAGE page, const char* pdf_name, int num) {
   for (int i = 0; i < annot_count; ++i) {
     // Retrieve the annotation object and its subtype.
     fprintf(fp, "Annotation #%d:\n", i + 1);
-    std::unique_ptr<void, FPDFAnnotationDeleter> annot(
-        FPDFPage_GetAnnot(page, i));
+    ScopedFPDFAnnotation annot(FPDFPage_GetAnnot(page, i));
     if (!annot) {
       fprintf(fp, "Failed to retrieve annotation!\n\n");
       continue;
@@ -579,8 +578,7 @@ void WriteImages(FPDF_PAGE page, const char* pdf_name, int page_num) {
     if (FPDFPageObj_GetType(obj) != FPDF_PAGEOBJ_IMAGE)
       continue;
 
-    std::unique_ptr<void, FPDFBitmapDeleter> bitmap(
-        FPDFImageObj_GetBitmap(obj));
+    ScopedFPDFBitmap bitmap(FPDFImageObj_GetBitmap(obj));
     if (!bitmap) {
       fprintf(stderr, "Image object #%d on page #%d has an empty bitmap.\n",
               i + 1, page_num + 1);