Merge to XFA: Return unique_ptrs from test_support functions

Orignal Review URL: https://codereview.chromium.org/1563513002 .
(cherry picked from commit aa326bd6b169dc1b5b9b83048c71799799ab34c6)

TBR=thestig@chromium.org

Review URL: https://codereview.chromium.org/1564583004 .

4 files changed, 30 insertions, 14 deletions

diff --git a/testing/embedder_test.cpp b/testing/embedder_test.cpp
index 7224e227c6..ceca205666 100644
--- a/testing/embedder_test.cpp
+++ b/testing/embedder_test.cpp
@@ -99,7 +99,6 @@ void EmbedderTest::TearDown() {
 #endif  // PDF_ENABLE_V8
 
   delete loader_;
-  free(file_contents_);
 }
 
 bool EmbedderTest::CreateEmptyDocument() {
@@ -120,7 +119,7 @@ bool EmbedderTest::OpenDocument(const std::string& filename,
   if (!file_contents_)
     return false;
 
-  loader_ = new TestLoader(file_contents_, file_length_);
+  loader_ = new TestLoader(file_contents_.get(), file_length_);
   file_access_.m_FileLen = static_cast<unsigned long>(file_length_);
   file_access_.m_GetBlock = TestLoader::GetBlock;
   file_access_.m_Param = loader_;
diff --git a/testing/embedder_test.h b/testing/embedder_test.h
index c780cca74b..a21a55de2c 100644
--- a/testing/embedder_test.h
+++ b/testing/embedder_test.h
@@ -14,6 +14,7 @@
 #include "public/fpdf_formfill.h"
 #include "public/fpdfview.h"
 #include "testing/gtest/include/gtest/gtest.h"
+#include "testing/test_support.h"
 
 #ifdef PDF_ENABLE_V8
 #include "v8/include/v8.h"
@@ -129,7 +130,7 @@ class EmbedderTest : public ::testing::Test,
   void* external_isolate_;
   TestLoader* loader_;
   size_t file_length_;
-  char* file_contents_;
+  std::unique_ptr<char, pdfium::FreeDeleter> file_contents_;
 
  private:
   static void UnsupportedHandlerTrampoline(UNSUPPORT_INFO*, int type);
diff --git a/testing/test_support.cpp b/testing/test_support.cpp
index c7ab10ee3c..ce143ae8e9 100644
--- a/testing/test_support.cpp
+++ b/testing/test_support.cpp
@@ -71,7 +71,8 @@ void InitializeV8Common(v8::Platform** platform) {
 
 }  // namespace
 
-char* GetFileContents(const char* filename, size_t* retlen) {
+std::unique_ptr<char, pdfium::FreeDeleter> GetFileContents(const char* filename,
+                                                           size_t* retlen) {
   FILE* file = fopen(filename, "rb");
   if (!file) {
     fprintf(stderr, "Failed to open: %s\n", filename);
@@ -83,15 +84,15 @@ char* GetFileContents(const char* filename, size_t* retlen) {
     return nullptr;
   }
   (void)fseek(file, 0, SEEK_SET);
-  char* buffer = (char*)malloc(file_length);
+  std::unique_ptr<char, pdfium::FreeDeleter> buffer(
+      static_cast<char*>(malloc(file_length)));
   if (!buffer) {
     return nullptr;
   }
-  size_t bytes_read = fread(buffer, 1, file_length, file);
+  size_t bytes_read = fread(buffer.get(), 1, file_length, file);
   (void)fclose(file);
   if (bytes_read != file_length) {
     fprintf(stderr, "Failed to read: %s\n", filename);
-    free(buffer);
     return nullptr;
   }
   *retlen = bytes_read;
@@ -114,9 +115,12 @@ std::wstring GetPlatformWString(FPDF_WIDESTRING wstr) {
   return platform_string;
 }
 
-FPDF_WIDESTRING GetFPDFWideString(const std::wstring& wstr) {
+std::unique_ptr<unsigned short, pdfium::FreeDeleter> GetFPDFWideString(
+    const std::wstring& wstr) {
   size_t length = sizeof(uint16_t) * (wstr.length() + 1);
-  unsigned char* ptr = static_cast<unsigned char*>(malloc(length));
+  std::unique_ptr<unsigned short, pdfium::FreeDeleter> result(
+      static_cast<unsigned short*>(malloc(length)));
+  char* ptr = reinterpret_cast<char*>(result.get());
   size_t i = 0;
   for (wchar_t w : wstr) {
     ptr[i++] = w & 0xff;
@@ -124,7 +128,7 @@ FPDF_WIDESTRING GetFPDFWideString(const std::wstring& wstr) {
   }
   ptr[i++] = 0;
   ptr[i] = 0;
-  return reinterpret_cast<FPDF_WIDESTRING>(ptr);
+  return result;
 }
 
 #ifdef PDF_ENABLE_V8
diff --git a/testing/test_support.h b/testing/test_support.h
index d48d5596f4..945704194d 100644
--- a/testing/test_support.h
+++ b/testing/test_support.h
@@ -6,6 +6,7 @@
 #define TESTING_EMBEDDER_TEST_SUPPORT_H_
 
 #include <stdlib.h>
+#include <memory>
 #include <string>
 
 #include "public/fpdfview.h"
@@ -14,16 +15,27 @@
 #include "v8/include/v8.h"
 #endif  // PDF_ENABLE_V8
 
-// Reads the entire contents of a file into a newly malloc'd buffer.
-char* GetFileContents(const char* filename, size_t* retlen);
+namespace pdfium {
+
+// Used with std::unique_ptr to free() objects that can't be deleted.
+struct FreeDeleter {
+  inline void operator()(void* ptr) const { free(ptr); }
+};
+
+}  // namespace pdfium
+
+// Reads the entire contents of a file into a newly alloc'd buffer.
+std::unique_ptr<char, pdfium::FreeDeleter> GetFileContents(const char* filename,
+                                                           size_t* retlen);
 
 // Converts a FPDF_WIDESTRING to a std::wstring.
 // Deals with differences between UTF16LE and wchar_t.
 std::wstring GetPlatformWString(const FPDF_WIDESTRING wstr);
 
-// Returns a newly mallocated FPDF_WIDESTRING (caller must free()).
+// Returns a newly allocated FPDF_WIDESTRING.
 // Deals with differences between UTF16LE and wchar_t.
-FPDF_WIDESTRING GetFPDFWideString(const std::wstring& wstr);
+std::unique_ptr<unsigned short, pdfium::FreeDeleter> GetFPDFWideString(
+    const std::wstring& wstr);
 
 #ifdef PDF_ENABLE_V8
 #ifdef V8_USE_EXTERNAL_STARTUP_DATA