handler: Write crash reports to a crash report database

handler/mac/crash_report_exception_handler.cc

+// Copyright 2015 The Crashpad Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "handler/mac/crash_report_exception_handler.h"
+
+#include "base/logging.h"
+#include "base/strings/stringprintf.h"
+#include "minidump/minidump_file_writer.h"
+#include "snapshot/mac/process_snapshot_mac.h"
+#include "util/file/file_writer.h"
+#include "util/mach/exception_behaviors.h"
+#include "util/mach/mach_extensions.h"
+#include "util/mach/scoped_task_suspend.h"
+#include "util/misc/uuid.h"
+
+namespace crashpad {
+
+namespace {
+
+// Calls CrashReportDatabase::ErrorWritingCrashReport() upon destruction unless
+// disarmed by calling Disarm(). Armed upon construction.
+class CallErrorWritingCrashReport {
+ public:
+  CallErrorWritingCrashReport(CrashReportDatabase* database,
+                              CrashReportDatabase::NewReport* new_report)
+      : database_(database),
+        new_report_(new_report) {
+  }
+
+  ~CallErrorWritingCrashReport() {
+    if (new_report_) {
+      database_->ErrorWritingCrashReport(new_report_);
+    }
+  }
+
+  void Disarm() {
+    new_report_ = nullptr;
+  }
+
+ private:
+  CrashReportDatabase* database_;  // weak
+  CrashReportDatabase::NewReport* new_report_;  // weak
+
+  DISALLOW_COPY_AND_ASSIGN(CallErrorWritingCrashReport);
+};
+
+}  // namespace
+
+CrashReportExceptionHandler::CrashReportExceptionHandler(
+    CrashReportDatabase* database)
+    : database_(database) {
+}
+
+CrashReportExceptionHandler::~CrashReportExceptionHandler() {
+}
+
+kern_return_t CrashReportExceptionHandler::CatchMachException(
+    exception_behavior_t behavior,
+    exception_handler_t exception_port,
+    thread_t thread,
+    task_t task,
+    exception_type_t exception,
+    const mach_exception_data_type_t* code,
+    mach_msg_type_number_t code_count,
+    thread_state_flavor_t* flavor,
+    const natural_t* old_state,
+    mach_msg_type_number_t old_state_count,
+    thread_state_t new_state,
+    mach_msg_type_number_t* new_state_count,
+    const mach_msg_trailer_t* trailer,
+    bool* destroy_complex_request) {
+  *destroy_complex_request = true;
+
+  // The expected behavior is EXCEPTION_STATE_IDENTITY | MACH_EXCEPTION_CODES,
+  // but it’s possible to deal with any exception behavior as long as it
+  // carries identity information (valid thread and task ports).
+  if (!ExceptionBehaviorHasIdentity(behavior)) {
+    LOG(ERROR) << base::StringPrintf(
+        "unexpected exception behavior 0x%x, rejecting", behavior);
+    return KERN_FAILURE;
+  } else if (behavior != (EXCEPTION_STATE_IDENTITY | kMachExceptionCodes)) {
+    LOG(WARNING) << base::StringPrintf(
+        "unexpected exception behavior 0x%x, proceeding", behavior);
+  }
+
+  if (task == mach_task_self()) {
+    LOG(ERROR) << "cannot suspend myself";
+    return KERN_FAILURE;
+  }
+
+  ScopedTaskSuspend suspend(task);
+
+  ProcessSnapshotMac process_snapshot;
+  if (!process_snapshot.Initialize(task)) {
+    return KERN_FAILURE;
+  }
+
+  CrashReportDatabase::NewReport* new_report;
+  CrashReportDatabase::OperationStatus database_status =
+      database_->PrepareNewCrashReport(&new_report);
+  if (database_status != CrashReportDatabase::kNoError) {
+    return KERN_FAILURE;
+  }
+
+  CallErrorWritingCrashReport call_error_writing_crash_report(database_,
+                                                              new_report);
+
+  WeakFileHandleFileWriter file_writer(new_report->handle);
+
+  MinidumpFileWriter minidump;
+  minidump.InitializeFromSnapshot(&process_snapshot);
+  if (!minidump.WriteEverything(&file_writer)) {
+    return KERN_FAILURE;
+  }
+
+  call_error_writing_crash_report.Disarm();
+
+  UUID uuid;
+  database_status = database_->FinishedWritingCrashReport(new_report, &uuid);
+  if (database_status != CrashReportDatabase::kNoError) {
+    return KERN_FAILURE;
+  }
+
+  return ExcServerSuccessfulReturnValue(behavior, false);
+}
+
+}  // namespace crashpad