Add Linux exception handler.

Add Linux stab symbol dumper.
Add minidump & symbol uploader for Linux.



git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@126 4c0a9323-5329-0410-9bdc-e9ce6186880e

src/client/linux/handler/exception_handler.cc

@@ -0,0 +1,236 @@
+// Copyright (c) 2006, Google Inc.
+// All rights reserved.
+//
+// Author: Li Liu
+//
+// 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.
+
+#include <asm/sigcontext.h>
+#include <signal.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include <cassert>
+#include <cstdlib>
+#include <ctime>
+
+#include "client/linux/handler/exception_handler.h"
+#include "common/linux/guid_creator.h"
+#include "google_breakpad/common/minidump_format.h"
+
+namespace google_breakpad {
+
+// Signals that we are interested.
+int SigTable[] = {
+#if defined(SIGSEGV)
+  SIGSEGV,
+#endif
+#ifdef SIGABRT
+  SIGABRT,
+#endif
+#ifdef SIGFPE
+  SIGFPE,
+#endif
+#ifdef SIGILL
+  SIGILL,
+#endif
+#ifdef SIGBUS
+  SIGBUS,
+#endif
+};
+
+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();
+    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() {
+  TeardownAllHandler();
+  pthread_mutex_lock(&handler_stack_mutex_);
+  if (handler_stack_->back() == this) {
+    handler_stack_->pop_back();
+  } else {
+    fprintf(stderr, "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, 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, NULL);
+}
+
+void ExceptionHandler::SetupHandler() {
+  // Signal on a different stack to avoid using the stack
+  // of the crashing thread.
+  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(SigTable) / sizeof(SigTable[0]); ++i)
+    SetupHandler(SigTable[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::TeardownAllHandler() {
+  for (size_t i = 0; i < sizeof(SigTable) / sizeof(SigTable[0]); ++i) {
+    TeardownHandler(SigTable[i]);
+  }
+}
+
+// static
+void ExceptionHandler::HandleException(int signo) {
+  // In Linux, 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. It is the second parameter above the signal number.
+  const struct sigcontext *sig_ctx =
+    reinterpret_cast<const struct sigcontext *>(&signo + 1);
+  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);
+  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, struct sigcontext);
+    SignalHandler old_handler =
+      reinterpret_cast<SignalHandler>(current_handler->old_handlers_[signo]);
+    if (old_handler != NULL)
+      old_handler(signo, *sig_ctx);
+  }
+
+  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,
+                                    const struct sigcontext *sig_ctx) {
+  if (filter_ && !filter_(callback_context_))
+      return false;
+
+  GUID guid;
+  bool success = false;;
+  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);
+    success = minidump_generator_.WriteMinidumpToFile(
+        minidump_path, signo, sig_ctx);
+    if (callback_)
+      success = callback_(dump_path_c_, guid_str,
+                          callback_context_, success);
+  }
+  return success;
+}
+
+}  // namespace google_breakpad