From 07e521c396be01162b4cb8119954401b7eaa510c Mon Sep 17 00:00:00 2001 From: "benchan@chromium.org" Date: Sat, 7 Jan 2012 02:25:22 +0000 Subject: Add utilities for processing Linux core dump files. This patch is part of a bigger patch that helps merging the breakpad code with the modified version in Chromium OS. Specifically, this patch makes the following changes: 1. Add an ElfCoreDump class for processing Linux core dump files, which will later be used to implement the core dump to minidump conversion. 2. Add a CrashGenerator class for generating a crash with a core dump file for testing the functionalities of ElfCoreDump. 3. Move some utility functions for reading/writing files to file_utils.h. BUG=455 TEST=Tested the following: 1. Build on 32-bit and 64-bit Linux with gcc 4.4.3 and gcc 4.6. 2. Build on Mac OS X 10.6.8 with gcc 4.2 and clang 3.0 (with latest gmock). 3. All unit tests pass. Review URL: http://breakpad.appspot.com/337001 git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@900 4c0a9323-5329-0410-9bdc-e9ce6186880e --- src/common/linux/tests/crash_generator.cc | 206 ++++++++++++++++++++++++++++++ 1 file changed, 206 insertions(+) create mode 100644 src/common/linux/tests/crash_generator.cc (limited to 'src/common/linux/tests/crash_generator.cc') diff --git a/src/common/linux/tests/crash_generator.cc b/src/common/linux/tests/crash_generator.cc new file mode 100644 index 00000000..3ef40dbd --- /dev/null +++ b/src/common/linux/tests/crash_generator.cc @@ -0,0 +1,206 @@ +// Copyright (c) 2011, 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. + +// crash_generator.cc: Implement google_breakpad::CrashGenerator. +// See crash_generator.h for details. + +#include "common/linux/tests/crash_generator.h" + +#include +#include +#include +#include +#include +#include +#include + +#include + +#include "common/linux/eintr_wrapper.h" +#include "common/tests/auto_tempdir.h" +#include "common/tests/file_utils.h" + +namespace { + +struct ThreadData { + pthread_t thread; + pthread_barrier_t* barrier; + pid_t* thread_id_ptr; +}; + +// Core file size limit set to 1 MB, which is big enough for test purposes. +const rlim_t kCoreSizeLimit = 1024 * 1024; + +void *thread_function(void *data) { + ThreadData* thread_data = reinterpret_cast(data); + volatile pid_t thread_id = syscall(__NR_gettid); + *(thread_data->thread_id_ptr) = thread_id; + int result = pthread_barrier_wait(thread_data->barrier); + if (result != 0 && result != PTHREAD_BARRIER_SERIAL_THREAD) { + exit(1); + } + while (true) { + pthread_yield(); + } +} + +} // namespace + +namespace google_breakpad { + +CrashGenerator::CrashGenerator() + : shared_memory_(NULL), + shared_memory_size_(0) { +} + +CrashGenerator::~CrashGenerator() { + UnmapSharedMemory(); +} + +bool CrashGenerator::HasDefaultCorePattern() const { + char buffer[8]; + ssize_t buffer_size = sizeof(buffer); + return ReadFile("/proc/sys/kernel/core_pattern", buffer, &buffer_size) && + buffer_size == 5 && memcmp(buffer, "core", 4) == 0; +} + +std::string CrashGenerator::GetCoreFilePath() const { + return temp_dir_.path() + "/core"; +} + +pid_t CrashGenerator::GetThreadId(unsigned index) const { + return reinterpret_cast(shared_memory_)[index]; +} + +pid_t* CrashGenerator::GetThreadIdPointer(unsigned index) { + return reinterpret_cast(shared_memory_) + index; +} + +bool CrashGenerator::MapSharedMemory(size_t memory_size) { + if (!UnmapSharedMemory()) + return false; + + void* mapped_memory = mmap(0, memory_size, PROT_READ | PROT_WRITE, + MAP_SHARED | MAP_ANONYMOUS, -1, 0); + if (mapped_memory == MAP_FAILED) + return false; + + memset(mapped_memory, 0, memory_size); + shared_memory_ = mapped_memory; + shared_memory_size_ = memory_size; + return true; +} + +bool CrashGenerator::UnmapSharedMemory() { + if (!shared_memory_) + return true; + + if (munmap(shared_memory_, shared_memory_size_) == 0) { + shared_memory_ = NULL; + shared_memory_size_ = 0; + return true; + } + return false; +} + +bool CrashGenerator::SetCoreFileSizeLimit(rlim_t limit) const { + struct rlimit limits = { limit, limit }; + return setrlimit(RLIMIT_CORE, &limits) == 0; +} + +bool CrashGenerator::CreateChildCrash( + unsigned num_threads, unsigned crash_thread, int crash_signal) { + if (num_threads == 0 || crash_thread >= num_threads) + return false; + + if (!MapSharedMemory(num_threads * sizeof(pid_t))) + return false; + + pid_t pid = fork(); + if (pid == 0) { + if (chdir(temp_dir_.path().c_str()) == 0 && + SetCoreFileSizeLimit(kCoreSizeLimit)) { + CreateThreadsInChildProcess(num_threads); + kill(*GetThreadIdPointer(crash_thread), crash_signal); + } + exit(1); + } + + int status; + if (HANDLE_EINTR(waitpid(pid, &status, 0)) == -1 || + !WIFSIGNALED(status) || WTERMSIG(status) != crash_signal) + return false; + + return true; +} + +void CrashGenerator::CreateThreadsInChildProcess(unsigned num_threads) { + *GetThreadIdPointer(0) = getpid(); + + if (num_threads <= 1) + return; + + // This method does not clean up any pthread resource, as the process + // is expected to be killed anyway. + ThreadData* thread_data = new ThreadData[num_threads]; + + // Create detached threads so that we do not worry about pthread_join() + // later being called or not. + pthread_attr_t thread_attributes; + if (pthread_attr_init(&thread_attributes) != 0 || + pthread_attr_setdetachstate(&thread_attributes, + PTHREAD_CREATE_DETACHED) != 0) { + exit(1); + } + + pthread_barrier_t thread_barrier; + if (pthread_barrier_init(&thread_barrier, NULL, num_threads) != 0) { + exit(1); + } + + for (unsigned i = 1; i < num_threads; ++i) { + thread_data[i].barrier = &thread_barrier; + thread_data[i].thread_id_ptr = GetThreadIdPointer(i); + if (pthread_create(&thread_data[i].thread, &thread_attributes, + thread_function, &thread_data[i]) != 0) { + exit(1); + } + } + + int result = pthread_barrier_wait(&thread_barrier); + if (result != 0 && result != PTHREAD_BARRIER_SERIAL_THREAD) { + exit(1); + } + + pthread_barrier_destroy(&thread_barrier); + pthread_attr_destroy(&thread_attributes); + delete[] thread_data; +} + +} // namespace google_breakpad -- cgit v1.2.1