Expose the Crashpad database path for direct use in the browser process.

This also paves the way for removing the awkward cross-module marshaling
of crash reports. With the Crasphad database path available, it's a
simple matter to construct a new database instance at need.

Bug: 806661
Change-Id: Ifd64f02bd7855de32163d91b6d2ad52404f9883e
Reviewed-on: https://chromium-review.googlesource.com/911594
Reviewed-by: Robert Shield <robertshield@chromium.org>
Reviewed-by: Scott Graham <scottmg@chromium.org>
Commit-Queue: Sigurður Ásgeirsson <siggi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#535792}

chrome_elf/chrome_elf_x64.def

@@ -9,6 +9,7 @@ EXPORTS
 
   ; From components/crash/content/app/crash_export_stubs.cc
   CrashForException_ExportThunk
+  GetCrashpadDatabasePath_ExportThunk
   GetCrashReports_ExportThunk
   InjectDumpForHungInput_ExportThunk
   RequestSingleCrashUpload_ExportThunk

chrome_elf/chrome_elf_x86.def

@@ -9,6 +9,7 @@ EXPORTS
 
   ; From components/crash/content/app/crash_export_stubs.cc
   CrashForException_ExportThunk
+  GetCrashpadDatabasePath_ExportThunk
   GetCrashReports_ExportThunk
   InjectDumpForHungInput_ExportThunk
   RequestSingleCrashUpload_ExportThunk

components/crash/content/app/crash_export_stubs.cc

@@ -31,6 +31,10 @@ HANDLE InjectDumpForHungInput_ExportThunk(HANDLE process) {
   return nullptr;
 }
 
+const wchar_t* GetCrashpadDatabasePath_ExportThunk() {
+  return nullptr;
+}
+
 #if defined(ARCH_CPU_X86_64)
 
 void RegisterNonABICompliantCodeRange_ExportThunk(void* start,

components/crash/content/app/crash_export_thunks.cc

@@ -60,6 +60,10 @@ HANDLE InjectDumpForHungInput_ExportThunk(HANDLE process) {
       nullptr);
 }
 
+const wchar_t* GetCrashpadDatabasePath_ExportThunk() {
+  return crash_reporter::GetCrashpadDatabasePathImpl();
+}
+
 #if defined(ARCH_CPU_X86_64)
 
 void RegisterNonABICompliantCodeRange_ExportThunk(void* start,

components/crash/content/app/crash_export_thunks.h

@@ -55,6 +55,9 @@ void SetUploadConsent_ExportThunk(bool consent);
 // This method is used solely to classify hung input.
 HANDLE InjectDumpForHungInput_ExportThunk(HANDLE process);
 
+// Returns the crashpad database path.
+const wchar_t* GetCrashpadDatabasePath_ExportThunk();
+
 #if defined(ARCH_CPU_X86_64)
 // V8 support functions.
 void RegisterNonABICompliantCodeRange_ExportThunk(void* start,

components/crash/content/app/crashpad.cc

@@ -46,6 +46,8 @@ namespace crash_reporter {
 
 namespace {
 
+base::FilePath* g_database_path;
+
 crashpad::CrashReportDatabase* g_database;
 
 bool LogMessageHandler(int severity,
@@ -87,6 +89,13 @@ bool LogMessageHandler(int severity,
   return false;
 }
 
+void InitializeDatabasePath(const base::FilePath& database_path) {
+  DCHECK(!g_database_path);
+
+  // Intentionally leaked.
+  g_database_path = new base::FilePath(database_path);
+}
+
 void InitializeCrashpadImpl(bool initial_client,
                             const std::string& process_type,
                             const std::string& user_data_dir,
@@ -172,6 +181,8 @@ void InitializeCrashpadImpl(bool initial_client,
   const bool should_initialize_database_and_set_upload_policy = initial_client;
 #endif
   if (should_initialize_database_and_set_upload_policy) {
+    InitializeDatabasePath(database_path);
+
     g_database =
         crashpad::CrashReportDatabase::Initialize(database_path).release();
 
@@ -275,6 +286,14 @@ void RequestSingleCrashUpload(const std::string& local_id) {
 #endif
 }
 
+base::FilePath GetCrashpadDatabasePath() {
+#if defined(OS_WIN)
+  return base::FilePath(GetCrashpadDatabasePath_ExportThunk());
+#else
+  return base::FilePath(GetCrashpadDatabasePathImpl());
+#endif
+}
+
 void GetReportsImpl(std::vector<Report>* reports) {
   reports->clear();
 
@@ -343,4 +362,11 @@ void RequestSingleCrashUploadImpl(const std::string& local_id) {
   g_database->RequestUpload(uuid);
 }
 
+base::FilePath::StringType::const_pointer GetCrashpadDatabasePathImpl() {
+  if (!g_database_path)
+    return nullptr;
+
+  return g_database_path->value().c_str();
+}
+
 }  // namespace crash_reporter

components/crash/content/app/crashpad.h

@@ -114,12 +114,18 @@ void RequestSingleCrashUpload(const std::string& local_id);
 
 void DumpWithoutCrashing();
 
+// Returns the Crashpad database path, only valid in the browser.
+base::FilePath GetCrashpadDatabasePath();
+
 // The implementation function for GetReports.
 void GetReportsImpl(std::vector<Report>* reports);
 
 // The implementation function for RequestSingleCrashUpload.
 void RequestSingleCrashUploadImpl(const std::string& local_id);
 
+// The implementation function for GetCrashpadDatabasePath.
+base::FilePath::StringType::const_pointer GetCrashpadDatabasePathImpl();
+
 namespace internal {
 
 #if defined(OS_WIN)