1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/toolkit/crashreporter/google-breakpad/src/client/linux/handler/exception_handler.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,275 @@
1.4 +// Copyright (c) 2010 Google Inc.
1.5 +// All rights reserved.
1.6 +//
1.7 +// Redistribution and use in source and binary forms, with or without
1.8 +// modification, are permitted provided that the following conditions are
1.9 +// met:
1.10 +//
1.11 +// * Redistributions of source code must retain the above copyright
1.12 +// notice, this list of conditions and the following disclaimer.
1.13 +// * Redistributions in binary form must reproduce the above
1.14 +// copyright notice, this list of conditions and the following disclaimer
1.15 +// in the documentation and/or other materials provided with the
1.16 +// distribution.
1.17 +// * Neither the name of Google Inc. nor the names of its
1.18 +// contributors may be used to endorse or promote products derived from
1.19 +// this software without specific prior written permission.
1.20 +//
1.21 +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
1.22 +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
1.23 +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
1.24 +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
1.25 +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
1.26 +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
1.27 +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
1.28 +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
1.29 +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
1.30 +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
1.31 +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.32 +
1.33 +#ifndef CLIENT_LINUX_HANDLER_EXCEPTION_HANDLER_H_
1.34 +#define CLIENT_LINUX_HANDLER_EXCEPTION_HANDLER_H_
1.35 +
1.36 +#include <string>
1.37 +#include <vector>
1.38 +
1.39 +#include <pthread.h>
1.40 +#include <signal.h>
1.41 +#include <stdint.h>
1.42 +#include <stdio.h>
1.43 +#include <sys/ucontext.h>
1.44 +
1.45 +#include "client/linux/crash_generation/crash_generation_client.h"
1.46 +#include "client/linux/handler/minidump_descriptor.h"
1.47 +#include "client/linux/minidump_writer/minidump_writer.h"
1.48 +#include "common/scoped_ptr.h"
1.49 +#include "common/using_std_string.h"
1.50 +#include "google_breakpad/common/minidump_format.h"
1.51 +
1.52 +namespace google_breakpad {
1.53 +
1.54 +// ExceptionHandler
1.55 +//
1.56 +// ExceptionHandler can write a minidump file when an exception occurs,
1.57 +// or when WriteMinidump() is called explicitly by your program.
1.58 +//
1.59 +// To have the exception handler write minidumps when an uncaught exception
1.60 +// (crash) occurs, you should create an instance early in the execution
1.61 +// of your program, and keep it around for the entire time you want to
1.62 +// have crash handling active (typically, until shutdown).
1.63 +// (NOTE): There should be only be one this kind of exception handler
1.64 +// object per process.
1.65 +//
1.66 +// If you want to write minidumps without installing the exception handler,
1.67 +// you can create an ExceptionHandler with install_handler set to false,
1.68 +// then call WriteMinidump. You can also use this technique if you want to
1.69 +// use different minidump callbacks for different call sites.
1.70 +//
1.71 +// In either case, a callback function is called when a minidump is written,
1.72 +// which receives the full path or file descriptor of the minidump. The
1.73 +// caller can collect and write additional application state to that minidump,
1.74 +// and launch an external crash-reporting application.
1.75 +//
1.76 +// Caller should try to make the callbacks as crash-friendly as possible,
1.77 +// it should avoid use heap memory allocation as much as possible.
1.78 +
1.79 +class ExceptionHandler {
1.80 + public:
1.81 + // A callback function to run before Breakpad performs any substantial
1.82 + // processing of an exception. A FilterCallback is called before writing
1.83 + // a minidump. |context| is the parameter supplied by the user as
1.84 + // callback_context when the handler was created.
1.85 + //
1.86 + // If a FilterCallback returns true, Breakpad will continue processing,
1.87 + // attempting to write a minidump. If a FilterCallback returns false,
1.88 + // Breakpad will immediately report the exception as unhandled without
1.89 + // writing a minidump, allowing another handler the opportunity to handle it.
1.90 + typedef bool (*FilterCallback)(void *context);
1.91 +
1.92 + // A callback function to run after the minidump has been written.
1.93 + // |descriptor| contains the file descriptor or file path containing the
1.94 + // minidump. |context| is the parameter supplied by the user as
1.95 + // callback_context when the handler was created. |succeeded| indicates
1.96 + // whether a minidump file was successfully written.
1.97 + //
1.98 + // If an exception occurred and the callback returns true, Breakpad will
1.99 + // treat the exception as fully-handled, suppressing any other handlers from
1.100 + // being notified of the exception. If the callback returns false, Breakpad
1.101 + // will treat the exception as unhandled, and allow another handler to handle
1.102 + // it. If there are no other handlers, Breakpad will report the exception to
1.103 + // the system as unhandled, allowing a debugger or native crash dialog the
1.104 + // opportunity to handle the exception. Most callback implementations
1.105 + // should normally return the value of |succeeded|, or when they wish to
1.106 + // not report an exception of handled, false. Callbacks will rarely want to
1.107 + // return true directly (unless |succeeded| is true).
1.108 + typedef bool (*MinidumpCallback)(const MinidumpDescriptor& descriptor,
1.109 + void* context,
1.110 + bool succeeded);
1.111 +
1.112 + // In certain cases, a user may wish to handle the generation of the minidump
1.113 + // themselves. In this case, they can install a handler callback which is
1.114 + // called when a crash has occurred. If this function returns true, no other
1.115 + // processing of occurs and the process will shortly be crashed. If this
1.116 + // returns false, the normal processing continues.
1.117 + typedef bool (*HandlerCallback)(const void* crash_context,
1.118 + size_t crash_context_size,
1.119 + void* context);
1.120 +
1.121 + // Creates a new ExceptionHandler instance to handle writing minidumps.
1.122 + // Before writing a minidump, the optional |filter| callback will be called.
1.123 + // Its return value determines whether or not Breakpad should write a
1.124 + // minidump. The minidump content will be written to the file path or file
1.125 + // descriptor from |descriptor|, and the optional |callback| is called after
1.126 + // writing the dump file, as described above.
1.127 + // If install_handler is true, then a minidump will be written whenever
1.128 + // an unhandled exception occurs. If it is false, minidumps will only
1.129 + // be written when WriteMinidump is called.
1.130 + // If |server_fd| is valid, the minidump is generated out-of-process. If it
1.131 + // is -1, in-process generation will always be used.
1.132 + ExceptionHandler(const MinidumpDescriptor& descriptor,
1.133 + FilterCallback filter,
1.134 + MinidumpCallback callback,
1.135 + void *callback_context,
1.136 + bool install_handler,
1.137 + const int server_fd);
1.138 + ~ExceptionHandler();
1.139 +
1.140 + const MinidumpDescriptor& minidump_descriptor() const {
1.141 + return minidump_descriptor_;
1.142 + }
1.143 +
1.144 + void set_minidump_descriptor(const MinidumpDescriptor& descriptor) {
1.145 + minidump_descriptor_ = descriptor;
1.146 + }
1.147 +
1.148 + void set_crash_handler(HandlerCallback callback) {
1.149 + crash_handler_ = callback;
1.150 + }
1.151 +
1.152 + // Writes a minidump immediately. This can be used to capture the execution
1.153 + // state independently of a crash.
1.154 + // Returns true on success.
1.155 + // If the ExceptionHandler has been created with a path, a new file is
1.156 + // generated for each minidump. The file path can be retrieved in the
1.157 + // MinidumpDescriptor passed to the MinidumpCallback or by accessing the
1.158 + // MinidumpDescriptor directly from the ExceptionHandler (with
1.159 + // minidump_descriptor()).
1.160 + // If the ExceptionHandler has been created with a file descriptor, the file
1.161 + // descriptor is repositioned to its beginning and the previous generated
1.162 + // minidump is overwritten.
1.163 + // Note that this method is not supposed to be called from a compromised
1.164 + // context as it uses the heap.
1.165 + bool WriteMinidump();
1.166 +
1.167 + // Convenience form of WriteMinidump which does not require an
1.168 + // ExceptionHandler instance.
1.169 + static bool WriteMinidump(const string& dump_path,
1.170 + MinidumpCallback callback,
1.171 + void* callback_context);
1.172 +
1.173 + // Write a minidump of |child| immediately. This can be used to
1.174 + // capture the execution state of |child| independently of a crash.
1.175 + // Pass a meaningful |child_blamed_thread| to make that thread in
1.176 + // the child process the one from which a crash signature is
1.177 + // extracted.
1.178 + //
1.179 + // WARNING: the return of this function *must* happen before
1.180 + // the code that will eventually reap |child| executes.
1.181 + // Otherwise there's a pernicious race condition in which |child|
1.182 + // exits, is reaped, another process created with its pid, then that
1.183 + // new process dumped.
1.184 + static bool WriteMinidumpForChild(pid_t child,
1.185 + pid_t child_blamed_thread,
1.186 + const string& dump_path,
1.187 + MinidumpCallback callback,
1.188 + void* callback_context);
1.189 +
1.190 + // This structure is passed to minidump_writer.h:WriteMinidump via an opaque
1.191 + // blob. It shouldn't be needed in any user code.
1.192 + struct CrashContext {
1.193 + siginfo_t siginfo;
1.194 + pid_t tid; // the crashing thread.
1.195 + struct ucontext context;
1.196 +#if !defined(__ARM_EABI__)
1.197 + // #ifdef this out because FP state is not part of user ABI for Linux ARM.
1.198 + struct _libc_fpstate float_state;
1.199 +#endif
1.200 + };
1.201 +
1.202 + // Returns whether out-of-process dump generation is used or not.
1.203 + bool IsOutOfProcess() const {
1.204 + return crash_generation_client_.get() != NULL;
1.205 + }
1.206 +
1.207 + // Add information about a memory mapping. This can be used if
1.208 + // a custom library loader is used that maps things in a way
1.209 + // that the linux dumper can't handle by reading the maps file.
1.210 + void AddMappingInfo(const string& name,
1.211 + const uint8_t identifier[sizeof(MDGUID)],
1.212 + uintptr_t start_address,
1.213 + size_t mapping_size,
1.214 + size_t file_offset);
1.215 +
1.216 + // Register a block of memory of length bytes starting at address ptr
1.217 + // to be copied to the minidump when a crash happens.
1.218 + void RegisterAppMemory(void* ptr, size_t length);
1.219 +
1.220 + // Unregister a block of memory that was registered with RegisterAppMemory.
1.221 + void UnregisterAppMemory(void* ptr);
1.222 +
1.223 + // Force signal handling for the specified signal.
1.224 + bool SimulateSignalDelivery(int sig);
1.225 +
1.226 + // Report a crash signal from an SA_SIGINFO signal handler.
1.227 + bool HandleSignal(int sig, siginfo_t* info, void* uc);
1.228 + private:
1.229 + // Save the old signal handlers and install new ones.
1.230 + static bool InstallHandlersLocked();
1.231 + // Restore the old signal handlers.
1.232 + static void RestoreHandlersLocked();
1.233 +
1.234 + void PreresolveSymbols();
1.235 + bool GenerateDump(CrashContext *context);
1.236 + void SendContinueSignalToChild();
1.237 + void WaitForContinueSignal();
1.238 +
1.239 + static void SignalHandler(int sig, siginfo_t* info, void* uc);
1.240 + static int ThreadEntry(void* arg);
1.241 + bool DoDump(pid_t crashing_process, const void* context,
1.242 + size_t context_size);
1.243 +
1.244 + const FilterCallback filter_;
1.245 + const MinidumpCallback callback_;
1.246 + void* const callback_context_;
1.247 +
1.248 + scoped_ptr<CrashGenerationClient> crash_generation_client_;
1.249 +
1.250 + MinidumpDescriptor minidump_descriptor_;
1.251 +
1.252 + HandlerCallback crash_handler_;
1.253 +
1.254 + // The global exception handler stack. This is need becuase there may exist
1.255 + // multiple ExceptionHandler instances in a process. Each will have itself
1.256 + // registered in this stack.
1.257 + static std::vector<ExceptionHandler*> *handler_stack_;
1.258 + static pthread_mutex_t handler_stack_mutex_;
1.259 +
1.260 + // We need to explicitly enable ptrace of parent processes on some
1.261 + // kernels, but we need to know the PID of the cloned process before we
1.262 + // can do this. We create a pipe which we can use to block the
1.263 + // cloned process after creating it, until we have explicitly enabled
1.264 + // ptrace. This is used to store the file descriptors for the pipe
1.265 + int fdes[2];
1.266 +
1.267 + // Callers can add extra info about mappings for cases where the
1.268 + // dumper code cannot extract enough information from /proc/<pid>/maps.
1.269 + MappingList mapping_list_;
1.270 +
1.271 + // Callers can request additional memory regions to be included in
1.272 + // the dump.
1.273 + AppMemoryList app_memory_list_;
1.274 +};
1.275 +
1.276 +} // namespace google_breakpad
1.277 +
1.278 +#endif // CLIENT_LINUX_HANDLER_EXCEPTION_HANDLER_H_
