Distinguish in the browser between renderer crashes and kills

components/crash/content/app/breakpad_linux.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.
 
 // For linux_syscall_support.h. This makes it safe to call embedded system
 // calls when in seccomp mode.
 
 #include "components/crash/content/app/breakpad_linux.h"
 
 #include <fcntl.h>
@@ skipping 78 matching lines @@
 bool g_is_crash_reporter_enabled = false;
 uint64_t g_process_start_time = 0;
 pid_t g_pid = 0;
 char* g_crash_log_path = nullptr;
 ExceptionHandler* g_breakpad = nullptr;
 
 #if defined(ADDRESS_SANITIZER)
 const char* g_asan_report_str = nullptr;
 #endif
 #if defined(OS_ANDROID)
+const char kWebViewProcessType[] = "webview";
 char* g_process_type = nullptr;
 ExceptionHandler* g_microdump = nullptr;
+int g_signal_code_pipe_fd = -1;
 
 class MicrodumpInfo {
  public:
   MicrodumpInfo()
       : microdump_build_fingerprint_(nullptr),
         microdump_product_info_(nullptr),
         microdump_gpu_fingerprint_(nullptr) {}
 
   // The order in which SetGpuFingerprint and Initialize are called
   // may be dependent on the timing of the availability of GPU
@@ skipping 619 matching lines @@
   // WARNING: this code runs in a compromised context. It may not call into
   // libc nor allocate memory normally.
   if (!succeeded) {
     static const char msg[] = "Microdump crash handler failed.\n";
     WriteLog(msg, sizeof(msg) - 1);
     return false;
   }
 
   const bool is_browser_process = (context != nullptr);
   return FinalizeCrashDoneAndroid(is_browser_process);
- }
+}
+
+bool WriteSignalCodeToPipe(const void* crash_context,
+                           size_t crash_context_size,
+                           void* context) {
+  if (g_signal_code_pipe_fd == -1)
+    return false;
+  int signo = 66;  // The code that doesn't correspond to any real signal.

[Torne, 2016/01/04 11:28:51]

Why 66 in particular? maximum int or something seems more reasonable as a magic
value..

[mnaganov (inactive), 2016/01/04 17:17:20]

Done.

+  if (crash_context_size == sizeof(ExceptionHandler::CrashContext)) {
+    const ExceptionHandler::CrashContext* eh_context =
+        static_cast<const ExceptionHandler::CrashContext*>(crash_context);
+    signo = eh_context->siginfo.si_signo;
+  }
+  sys_write(g_signal_code_pipe_fd, &signo, sizeof(signo));
+  IGNORE_RET(sys_close(g_signal_code_pipe_fd));
+  g_signal_code_pipe_fd = -1;
+  return false;
+}
 
 bool CrashDoneInProcessNoUpload(
     const google_breakpad::MinidumpDescriptor& descriptor,
     void* context,
     const bool succeeded) {
   // WARNING: this code runs in a compromised context. It may not call into
   // libc nor allocate memory normally.
   if (!succeeded) {
     static const char msg[] = "Crash dump generation failed.\n";
     WriteLog(msg, sizeof(msg) - 1);
@@ skipping 72 matching lines @@
     g_microdump->set_minidump_descriptor(minidump_descriptor);
   }
 }
 
 void MicrodumpInfo::Initialize(const std::string& process_type,
                                const char* product_name,
                                const char* product_version,
                                const char* android_build_fp) {
   DCHECK(thread_checker_.CalledOnValidThread());
   DCHECK(!g_microdump);
-  bool is_browser_process = process_type.empty() || process_type == "webview";
+  bool is_browser_process =
+      process_type.empty() || process_type == kWebViewProcessType;
 
   MinidumpDescriptor descriptor(MinidumpDescriptor::kMicrodumpOnConsole);
 
   if (product_name && product_version) {
     microdump_product_info_ =
         strdup((product_name + std::string(":") + product_version).c_str());
     ANNOTATE_LEAKING_OBJECT_PTR(microdump_product_info_);
     descriptor.microdump_extra_info()->product_info = microdump_product_info_;
   }
 
   if (android_build_fp) {
     microdump_build_fingerprint_ = strdup(android_build_fp);
     ANNOTATE_LEAKING_OBJECT_PTR(microdump_build_fingerprint_);
     descriptor.microdump_extra_info()->build_fingerprint =
         microdump_build_fingerprint_;
   }
 
   if (microdump_gpu_fingerprint_) {
     descriptor.microdump_extra_info()->gpu_fingerprint =
         microdump_gpu_fingerprint_;
   }
 
   g_microdump =
       new ExceptionHandler(descriptor, nullptr, MicrodumpCrashDone,
                            reinterpret_cast<void*>(is_browser_process),
                            true,  // Install handlers.
                            -1);   // Server file descriptor. -1 for in-process.
 
-  if (process_type == "webview") {
+  if (process_type == kWebViewProcessType) {
     // We do not use |DumpProcess()| for handling programatically
     // generated dumps for WebView because we only know the file
     // descriptor to which we are dumping at the time of the call to
     // |DumpWithoutCrashing()|. Therefore we need to construct the
     // |MinidumpDescriptor| and |ExceptionHandler| instances as
     // needed, instead of setting up |g_breakpad| at initialization
     // time.
     base::debug::SetDumpWithoutCrashingFunction(
         &GenerateMinidumpOnDemandForAndroid);
+  } else if (!process_type.empty()) {
+    g_signal_code_pipe_fd =
+        GetCrashReporterClient()->GetAndroidMinidumpDescriptor();
+    if (g_signal_code_pipe_fd != -1)
+      g_microdump->set_crash_handler(WriteSignalCodeToPipe);
   }
 }
 
 #else
 // Non-Browser = Extension, Gpu, Plugins, Ppapi and Renderer
 class NonBrowserCrashHandler : public google_breakpad::CrashGenerationClient {
  public:
   NonBrowserCrashHandler()
       : server_fd_(base::GlobalDescriptors::GetInstance()->Get(
             kCrashDumpSignal)) {
@@ skipping 980 matching lines @@
     const std::string& gpu_fingerprint) {
   g_microdump_info.Get().SetGpuFingerprint(gpu_fingerprint);
 }
 #endif  // OS_ANDROID
 
 bool IsCrashReporterEnabled() {
   return g_is_crash_reporter_enabled;
 }
 
 }  // namespace breakpad