Transfer v8 snapshot files as file descriptors to child processes on Posix

gin/isolate_holder.cc

 // Copyright 2013 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 "gin/public/isolate_holder.h"
 
 #include <stdlib.h>
 #include <string.h>
 
 #include "base/files/memory_mapped_file.h"
@@ skipping 88 matching lines @@
 bool VerifyV8SnapshotFile(base::MemoryMappedFile* snapshot_file,
                           const unsigned char* fingerprint) {
   unsigned char output[crypto::kSHA256Length];
   crypto::SHA256HashString(
       base::StringPiece(reinterpret_cast<const char*>(snapshot_file->data()),
                         snapshot_file->length()),
       output, sizeof(output));
   return !memcmp(fingerprint, output, sizeof(output));
 }
 #endif  // V8_VERIFY_EXTERNAL_STARTUP_DATA
-
-#if !defined(OS_MACOSX)
-const int v8_snapshot_dir =
-#if defined(OS_ANDROID)
-    base::DIR_ANDROID_APP_DATA;
-#elif defined(OS_POSIX)
-    base::DIR_EXE;
-#elif defined(OS_WIN)
-    base::DIR_MODULE;
-#endif  // OS_ANDROID
-#endif  // !OS_MACOSX
-
 #endif  // V8_USE_EXTERNAL_STARTUP_DATA
 
 }  // namespace
 
 #if defined(V8_USE_EXTERNAL_STARTUP_DATA)
 
 #if defined(V8_VERIFY_EXTERNAL_STARTUP_DATA)
 // Defined in gen/gin/v8_snapshot_fingerprint.cc
 extern const unsigned char g_natives_fingerprint[];
 extern const unsigned char g_snapshot_fingerprint[];
 #endif  // V8_VERIFY_EXTERNAL_STARTUP_DATA
 
+#if !defined(OS_MACOSX)
+const int IsolateHolder::kV8SnapshotBasePathKey =
+#if defined(OS_ANDROID)
+    base::DIR_ANDROID_APP_DATA;
+#elif defined(OS_POSIX)
+    base::DIR_EXE;
+#elif defined(OS_WIN)
+    base::DIR_MODULE;
+#endif  // OS_ANDROID
+#endif  // !OS_MACOSX
+
 const char IsolateHolder::kNativesFileName[] = "natives_blob.bin";
 const char IsolateHolder::kSnapshotFileName[] = "snapshot_blob.bin";
 
 // static
 bool IsolateHolder::LoadV8Snapshot() {
   if (g_mapped_natives && g_mapped_snapshot)
     return true;
 
 #if !defined(OS_MACOSX)
   base::FilePath data_path;
-  PathService::Get(v8_snapshot_dir, &data_path);
+  PathService::Get(kV8SnapshotBasePathKey, &data_path);
   DCHECK(!data_path.empty());
 
   base::FilePath natives_path = data_path.AppendASCII(kNativesFileName);
   base::FilePath snapshot_path = data_path.AppendASCII(kSnapshotFileName);
 #else  // !defined(OS_MACOSX)
   base::ScopedCFTypeRef<CFStringRef> natives_file_name(
       base::SysUTF8ToCFStringRef(kNativesFileName));
   base::FilePath natives_path = base::mac::PathForFrameworkBundleResource(
       natives_file_name);
   base::ScopedCFTypeRef<CFStringRef> snapshot_file_name(
@@ skipping 143 matching lines @@
   base::MessageLoop::current()->AddTaskObserver(task_observer_.get());
 }
 
 void IsolateHolder::RemoveRunMicrotasksObserver() {
   DCHECK(task_observer_.get());
   base::MessageLoop::current()->RemoveTaskObserver(task_observer_.get());
   task_observer_.reset();
 }
 
 }  // namespace gin