The Tor Browser: toolkit/crashreporter/google-breakpad/src/client/solaris/handler/exception

toolkit/crashreporter/google-breakpad/src/client/solaris/handler/exception_handler.cc@6474c204b198 (annotated)

toolkit/crashreporter/google-breakpad/src/client/solaris/handler/exception_handler.cc

Wed, 31 Dec 2014 06:09:35 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Wed, 31 Dec 2014 06:09:35 +0100
changeset 0: 6474c204b198
permissions: -rw-r--r--

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

 // Copyright (c) 2007, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 // notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 // copyright notice, this list of conditions and the following disclaimer
 // in the documentation and/or other materials provided with the
 // distribution.
 //     * Neither the name of Google Inc. nor the names of its
 // contributors may be used to endorse or promote products derived from
 // this software without specific prior written permission.
 //
 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 // Author: Alfred Peng
 #include <signal.h>
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <unistd.h>
 #include <cassert>
 #include <cstdlib>
 #include <ctime>
 #include "client/solaris/handler/exception_handler.h"
 #include "common/solaris/guid_creator.h"
 #include "common/solaris/message_output.h"
 #include "google_breakpad/common/minidump_format.h"
 namespace google_breakpad {
 // Signals that we are interested.
 static const int kSigTable[] = {
   SIGSEGV,
   SIGABRT,
   SIGFPE,
   SIGILL,
   SIGBUS
 };
 std::vector<ExceptionHandler*> *ExceptionHandler::handler_stack_ = NULL;
 int ExceptionHandler::handler_stack_index_ = 0;
 pthread_mutex_t ExceptionHandler::handler_stack_mutex_ =
   PTHREAD_MUTEX_INITIALIZER;
 ExceptionHandler::ExceptionHandler(const string &dump_path,
                                    FilterCallback filter,
                                    MinidumpCallback callback,
                                    void *callback_context,
                                    bool install_handler)
     : filter_(filter),
       callback_(callback),
       callback_context_(callback_context),
       dump_path_(),
       installed_handler_(install_handler) {
   set_dump_path(dump_path);
   if (install_handler) {
     SetupHandler();
   }
   if (install_handler) {
     pthread_mutex_lock(&handler_stack_mutex_);
     if (handler_stack_ == NULL)
       handler_stack_ = new std::vector<ExceptionHandler *>;
     handler_stack_->push_back(this);
     pthread_mutex_unlock(&handler_stack_mutex_);
   }
 }
 ExceptionHandler::~ExceptionHandler() {
   TeardownAllHandlers();
   pthread_mutex_lock(&handler_stack_mutex_);
   if (handler_stack_->back() == this) {
     handler_stack_->pop_back();
   } else {
     print_message1(2, "warning: removing Breakpad handler out of order\n");
     for (std::vector<ExceptionHandler *>::iterator iterator =
          handler_stack_->begin();
          iterator != handler_stack_->end();
          ++iterator) {
       if (*iterator == this) {
         handler_stack_->erase(iterator);
       }
     }
   }
   if (handler_stack_->empty()) {
     // When destroying the last ExceptionHandler that installed a handler,
     // clean up the handler stack.
     delete handler_stack_;
     handler_stack_ = NULL;
   }
   pthread_mutex_unlock(&handler_stack_mutex_);
 }
 bool ExceptionHandler::WriteMinidump() {
   return InternalWriteMinidump(0, 0, NULL);
 }
 // static
 bool ExceptionHandler::WriteMinidump(const string &dump_path,
                                      MinidumpCallback callback,
                                      void *callback_context) {
   ExceptionHandler handler(dump_path, NULL, callback,
                            callback_context, false);
   return handler.InternalWriteMinidump(0, 0, NULL);
 }
 void ExceptionHandler::SetupHandler() {
   // Signal on a different stack to avoid using the stack
   // of the crashing lwp.
   struct sigaltstack sig_stack;
   sig_stack.ss_sp = malloc(MINSIGSTKSZ);
   if (sig_stack.ss_sp == NULL)
     return;
   sig_stack.ss_size = MINSIGSTKSZ;
   sig_stack.ss_flags = 0;
   if (sigaltstack(&sig_stack, NULL) < 0)
     return;
   for (size_t i = 0; i < sizeof(kSigTable) / sizeof(kSigTable[0]); ++i)
     SetupHandler(kSigTable[i]);
 }
 void ExceptionHandler::SetupHandler(int signo) {
   struct sigaction act, old_act;
   act.sa_handler = HandleException;
   act.sa_flags = SA_ONSTACK;
   if (sigaction(signo, &act, &old_act) < 0)
     return;
   old_handlers_[signo] = old_act.sa_handler;
 }
 void ExceptionHandler::TeardownHandler(int signo) {
   if (old_handlers_.find(signo) != old_handlers_.end()) {
     struct sigaction act;
     act.sa_handler = old_handlers_[signo];
     act.sa_flags = 0;
     sigaction(signo, &act, 0);
   }
 }
 void ExceptionHandler::TeardownAllHandlers() {
   for (size_t i = 0; i < sizeof(kSigTable) / sizeof(kSigTable[0]); ++i) {
     TeardownHandler(kSigTable[i]);
   }
 }
 // static
 void ExceptionHandler::HandleException(int signo) {
 //void ExceptionHandler::HandleException(int signo, siginfo_t *sip, ucontext_t *sig_ctx) {
   // The context information about the signal is put on the stack of
   // the signal handler frame as value parameter. For some reasons, the
   // prototype of the handler doesn't declare this information as parameter, we
   // will do it by hand. The stack layout for a signal handler frame is here:
   // http://src.opensolaris.org/source/xref/onnv/onnv-gate/usr/src/lib/libproc/common/Pstack.c#81
   //
   // However, if we are being called by another signal handler passing the
   // signal up the chain, then we may not have this random extra parameter,
   // so we may have to walk the stack to find it.  We do the actual work
   // on another thread, where it's a little safer, but we want the ebp
   // from this frame to find it.
   uintptr_t current_ebp = (uintptr_t)_getfp();
   pthread_mutex_lock(&handler_stack_mutex_);
   ExceptionHandler *current_handler =
     handler_stack_->at(handler_stack_->size() - ++handler_stack_index_);
   pthread_mutex_unlock(&handler_stack_mutex_);
   // Restore original handler.
   current_handler->TeardownHandler(signo);
   ucontext_t *sig_ctx = NULL;
   if (current_handler->InternalWriteMinidump(signo, current_ebp, &sig_ctx)) {
 //  if (current_handler->InternalWriteMinidump(signo, &sig_ctx)) {
     // Fully handled this exception, safe to exit.
     exit(EXIT_FAILURE);
   } else {
     // Exception not fully handled, will call the next handler in stack to
     // process it.
     typedef void (*SignalHandler)(int signo);
     SignalHandler old_handler =
       reinterpret_cast<SignalHandler>(current_handler->old_handlers_[signo]);
     if (old_handler != NULL)
       old_handler(signo);
   }
   pthread_mutex_lock(&handler_stack_mutex_);
   current_handler->SetupHandler(signo);
   --handler_stack_index_;
   // All the handlers in stack have been invoked to handle the exception,
   // normally the process should be terminated and should not reach here.
   // In case we got here, ask the OS to handle it to avoid endless loop,
   // normally the OS will generate a core and termiate the process. This
   // may be desired to debug the program.
   if (handler_stack_index_ == 0)
     signal(signo, SIG_DFL);
   pthread_mutex_unlock(&handler_stack_mutex_);
 }
 bool ExceptionHandler::InternalWriteMinidump(int signo,
                                              uintptr_t sighandler_ebp,
                                              ucontext_t **sig_ctx) {
   if (filter_ && !filter_(callback_context_))
     return false;
   bool success = false;
   GUID guid;
   char guid_str[kGUIDStringLength + 1];
   if (CreateGUID(&guid) && GUIDToString(&guid, guid_str, sizeof(guid_str))) {
     char minidump_path[PATH_MAX];
     snprintf(minidump_path, sizeof(minidump_path), "%s/%s.dmp",
              dump_path_c_, guid_str);
     // Block all the signals we want to process when writing minidump.
     // We don't want it to be interrupted.
     sigset_t sig_blocked, sig_old;
     bool blocked = true;
     sigfillset(&sig_blocked);
     for (size_t i = 0; i < sizeof(kSigTable) / sizeof(kSigTable[0]); ++i)
       sigdelset(&sig_blocked, kSigTable[i]);
     if (sigprocmask(SIG_BLOCK, &sig_blocked, &sig_old) != 0) {
       blocked = false;
       print_message1(2, "HandleException: failed to block signals.\n");
     }
     success = minidump_generator_.WriteMinidumpToFile(
                        minidump_path, signo, sighandler_ebp, sig_ctx);
     // Unblock the signals.
     if (blocked)
       sigprocmask(SIG_SETMASK, &sig_old, &sig_old);
     if (callback_)
       success = callback_(dump_path_c_, guid_str, callback_context_, success);
   }
   return success;
 }
 }  // namespace google_breakpad

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toolkit/crashreporter/google-breakpad/src/client/solaris/handler/exception_handler.cc@6474c204b198 (annotated)

toolkit/crashreporter/google-breakpad/src/client/solaris/handler/exception_handler.cc