Creating minidump for uncaught exception on iOS.

This CL adds a minidump_generator that can write a minidump from a NSException
on iOS on an ARM cpu.

 This CL also install an uncaught exception handler on iOS, and use the
previous generator to write minidumps for any uncaught exception.
Review URL: https://breakpad.appspot.com/347001

git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@916 4c0a9323-5329-0410-9bdc-e9ce6186880e

src/client/ios/Breakpad.mm

@@ -45,6 +45,7 @@
 #import "client/mac/handler/exception_handler.h"
 #import "client/mac/handler/minidump_generator.h"
 #import "client/ios/Breakpad.h"
+#import "client/ios/handler/ios_exception_minidump_generator.h"
 #import "client/mac/handler/protected_memory_allocator.h"
 
 #import <sys/stat.h>
@@ -174,6 +175,12 @@ class Breakpad {
   bool HandleMinidump(const char *dump_dir,
                       const char *minidump_id);
 
+  // NSException handler
+  static void UncaughtExceptionHandler(NSException *exception);
+
+  // Handle an uncaught NSException.
+  void HandleUncaughtException(NSException *exception);
+
   // Since ExceptionHandler (w/o namespace) is defined as typedef in OSX's
   // MachineExceptions.h, we have to explicitly name the handler.
   google_breakpad::ExceptionHandler *handler_; // The actual handler (STRONG)
@@ -181,8 +188,14 @@ class Breakpad {
   SimpleStringDictionary  *config_params_; // Create parameters (STRONG)
 
   ConfigFile config_file_;
+
+  // A static reference to the current Breakpad instance. Used for handling
+  // NSException.
+  static Breakpad *current_breakpad_;
 };
 
+Breakpad *Breakpad::current_breakpad_ = NULL;
+
 #pragma mark -
 #pragma mark Helper functions
 
@@ -240,12 +253,21 @@ bool Breakpad::HandleMinidumpCallback(const char *dump_dir,
   return breakpad->HandleMinidump(dump_dir, minidump_id);
 }
 
+//=============================================================================
+void Breakpad::UncaughtExceptionHandler(NSException *exception) {
+  NSSetUncaughtExceptionHandler(NULL);
+  if (current_breakpad_) {
+    current_breakpad_->HandleUncaughtException(exception);
+  }
+}
+
 //=============================================================================
 #pragma mark -
 
 //=============================================================================
 bool Breakpad::Initialize(NSDictionary *parameters) {
   // Initialize
+  current_breakpad_ = this;
   config_params_ = NULL;
   handler_ = NULL;
 
@@ -267,11 +289,14 @@ bool Breakpad::Initialize(NSDictionary *parameters) {
           google_breakpad::ExceptionHandler(
               config_params_->GetValueForKey(BREAKPAD_DUMP_DIRECTORY),
               0, &HandleMinidumpCallback, this, true, 0);
+  NSSetUncaughtExceptionHandler(&Breakpad::UncaughtExceptionHandler);
   return true;
 }
 
 //=============================================================================
 Breakpad::~Breakpad() {
+  NSSetUncaughtExceptionHandler(NULL);
+  current_breakpad_ = NULL;
   // Note that we don't use operator delete() on these pointers,
   // since they were allocated by ProtectedMemoryAllocator objects.
   //
@@ -499,6 +524,37 @@ bool Breakpad::HandleMinidump(const char *dump_dir,
 }
 
 //=============================================================================
+void Breakpad::HandleUncaughtException(NSException *exception) {
+  // Generate the minidump.
+  google_breakpad::IosExceptionMinidumpGenerator generator(exception);
+  const char *minidump_path =
+      config_params_->GetValueForKey(BREAKPAD_DUMP_DIRECTORY);
+  std::string minidump_id;
+  std::string minidump_filename = generator.UniqueNameInDirectory(minidump_path,
+                                                                  &minidump_id);
+  generator.Write(minidump_filename.c_str());
+
+  // Copy the config params and our custom parameter. This is necessary for 2
+  // reasons:
+  // 1- config_params_ is protected.
+  // 2- If the application crash while trying to handle this exception, a usual
+  //    report will be generated. This report must not contain these special
+  //    keys.
+  SimpleStringDictionary params = *config_params_;
+  params.SetKeyValue(BREAKPAD_SERVER_PARAMETER_PREFIX "type", "exception");
+  params.SetKeyValue(BREAKPAD_SERVER_PARAMETER_PREFIX "exceptionName",
+                     [[exception name] UTF8String]);
+  params.SetKeyValue(BREAKPAD_SERVER_PARAMETER_PREFIX "exceptionReason",
+                     [[exception reason] UTF8String]);
+
+  // And finally write the config file.
+  ConfigFile config_file;
+  config_file.WriteFile(minidump_path,
+                        &params,
+                        minidump_path,
+                        minidump_id.c_str());
+}
+
 //=============================================================================
 
 #pragma mark -

src/client/ios/Breakpad.xcodeproj/project.pbxproj

@@ -7,6 +7,8 @@
 	objects = {
 
 /* Begin PBXBuildFile section */
+		16BFA67014E195E9009704F8 /* ios_exception_minidump_generator.h in Headers */ = {isa = PBXBuildFile; fileRef = 16BFA66E14E195E9009704F8 /* ios_exception_minidump_generator.h */; };
+		16BFA67214E1965A009704F8 /* ios_exception_minidump_generator.mm in Sources */ = {isa = PBXBuildFile; fileRef = 16BFA67114E1965A009704F8 /* ios_exception_minidump_generator.mm */; };
 		16C7CCCB147D4A4300776EAD /* BreakpadDefines.h in Headers */ = {isa = PBXBuildFile; fileRef = 16C7C968147D4A4200776EAD /* BreakpadDefines.h */; };
 		16C7CCCC147D4A4300776EAD /* Breakpad.h in Headers */ = {isa = PBXBuildFile; fileRef = 16C7C96A147D4A4200776EAD /* Breakpad.h */; };
 		16C7CCCD147D4A4300776EAD /* Breakpad.mm in Sources */ = {isa = PBXBuildFile; fileRef = 16C7C96B147D4A4200776EAD /* Breakpad.mm */; };
@@ -55,6 +57,8 @@
 /* End PBXBuildFile section */
 
 /* Begin PBXFileReference section */
+		16BFA66E14E195E9009704F8 /* ios_exception_minidump_generator.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ios_exception_minidump_generator.h; sourceTree = "<group>"; };
+		16BFA67114E1965A009704F8 /* ios_exception_minidump_generator.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = ios_exception_minidump_generator.mm; sourceTree = "<group>"; };
 		16C7C968147D4A4200776EAD /* BreakpadDefines.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = BreakpadDefines.h; sourceTree = "<group>"; };
 		16C7C96A147D4A4200776EAD /* Breakpad.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = Breakpad.h; sourceTree = "<group>"; };
 		16C7C96B147D4A4200776EAD /* Breakpad.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = Breakpad.mm; sourceTree = "<group>"; };
@@ -151,6 +155,15 @@
 			name = Classes;
 			sourceTree = "<group>";
 		};
+		16BFA66A14E195E9009704F8 /* handler */ = {
+			isa = PBXGroup;
+			children = (
+				16BFA67114E1965A009704F8 /* ios_exception_minidump_generator.mm */,
+				16BFA66E14E195E9009704F8 /* ios_exception_minidump_generator.h */,
+			);
+			path = handler;
+			sourceTree = "<group>";
+		};
 		16C7C965147D4A4200776EAD /* client */ = {
 			isa = PBXGroup;
 			children = (
@@ -185,6 +198,7 @@
 		16C7C969147D4A4200776EAD /* ios */ = {
 			isa = PBXGroup;
 			children = (
+				16BFA66A14E195E9009704F8 /* handler */,
 				16C7C96A147D4A4200776EAD /* Breakpad.h */,
 				16C7C96B147D4A4200776EAD /* Breakpad.mm */,
 			);
@@ -312,6 +326,7 @@
 				16C7CE90147D4A4300776EAD /* string_utilities.h in Headers */,
 				16C7CE94147D4A4300776EAD /* md5.h in Headers */,
 				16C7CEA8147D4A4300776EAD /* string_conversion.h in Headers */,
+				16BFA67014E195E9009704F8 /* ios_exception_minidump_generator.h in Headers */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};
@@ -397,6 +412,7 @@
 				16C7CE8F147D4A4300776EAD /* string_utilities.cc in Sources */,
 				16C7CE93147D4A4300776EAD /* md5.cc in Sources */,
 				16C7CEA7147D4A4300776EAD /* string_conversion.cc in Sources */,
+				16BFA67214E1965A009704F8 /* ios_exception_minidump_generator.mm in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};
@@ -415,7 +431,6 @@
 					"\"$(SRCROOT)/../mac/build/Debug\"",
 				);
 				GCC_DYNAMIC_NO_PIC = NO;
-				GCC_ENABLE_FIX_AND_CONTINUE = YES;
 				GCC_MODEL_TUNING = G5;
 				GCC_OPTIMIZATION_LEVEL = 0;
 				GCC_PRECOMPILE_PREFIX_HEADER = YES;
@@ -479,7 +494,6 @@
 					../../common/mac,
 				);
 				OTHER_LDFLAGS = "-ObjC";
-				PREBINDING = NO;
 				SDKROOT = iphoneos;
 			};
 			name = Debug;
@@ -497,7 +511,6 @@
 					../../common/mac,
 				);
 				OTHER_LDFLAGS = "-ObjC";
-				PREBINDING = NO;
 				SDKROOT = iphoneos;
 			};
 			name = Release;

src/client/ios/handler/ios_exception_minidump_generator.h

@@ -0,0 +1,64 @@
+// Copyright (c) 2012, 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.
+
+// ios_exception_minidump_generator.h:  Create a fake minidump from a
+// NSException.
+
+#ifndef CLIENT_IOS_HANDLER_IOS_EXCEPTION_MINIDUMP_GENERATOR_H_
+#define CLIENT_IOS_HANDLER_IOS_EXCEPTION_MINIDUMP_GENERATOR_H_
+
+#include <Foundation/Foundation.h>
+
+#include "client/mac/handler/minidump_generator.h"
+
+namespace google_breakpad {
+
+class IosExceptionMinidumpGenerator : public MinidumpGenerator {
+ public:
+  explicit IosExceptionMinidumpGenerator(NSException *exception);
+  virtual ~IosExceptionMinidumpGenerator();
+
+ protected:
+  virtual bool WriteExceptionStream(MDRawDirectory *exception_stream);
+  virtual bool WriteThreadStream(mach_port_t thread_id, MDRawThread *thread);
+
+ private:
+
+  // Get the crashing program counter from the exception.
+  uint32_t GetPCFromException();
+
+  // Write a virtual thread context for the crashing site.
+  bool WriteCrashingContext(MDLocationDescriptor *register_location);
+
+  NSArray *return_addresses_;
+};
+
+}  // namespace google_breakpad
+
+#endif  // CLIENT_IOS_HANDLER_IOS_EXCEPTION_MINIDUMP_GENERATOR_H_

src/client/ios/handler/ios_exception_minidump_generator.mm

@@ -0,0 +1,164 @@
+// Copyright (c) 2012, 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.
+
+#include "client/ios/handler/ios_exception_minidump_generator.h"
+
+#include "processor/scoped_ptr.h"
+
+namespace {
+
+const uint32_t kExpectedFinalFp = 4;
+const uint32_t kExpectedFinalSp = 0;
+const int kExceptionType = EXC_SOFTWARE;
+const int kExceptionCode = 0xDEADBEEF;
+
+// Append the given 4 bytes value to the sp position of the stack represented
+// by memory.
+void AppendToMemory(uint8_t *memory, uint32_t sp, uint32_t data) {
+  assert(sizeof(data) == 4);
+  memcpy(memory + sp, &data, sizeof(data));
+}
+
+}  // namespace
+
+namespace google_breakpad {
+
+IosExceptionMinidumpGenerator::IosExceptionMinidumpGenerator(
+    NSException *exception)
+    : MinidumpGenerator(mach_task_self(), 0) {
+  return_addresses_ = [[exception callStackReturnAddresses] retain];
+  SetExceptionInformation(kExceptionType,
+                          kExceptionCode,
+                          0,
+                          pthread_mach_thread_np(pthread_self()));
+}
+
+IosExceptionMinidumpGenerator::~IosExceptionMinidumpGenerator() {
+  [return_addresses_ release];
+}
+
+bool IosExceptionMinidumpGenerator::WriteCrashingContext(
+    MDLocationDescriptor *register_location) {
+#ifdef HAS_ARM_SUPPORT
+  TypedMDRVA<MDRawContextARM> context(&writer_);
+  if (!context.Allocate())
+    return false;
+  *register_location = context.location();
+  MDRawContextARM *context_ptr = context.get();
+  memset(context_ptr, 0, sizeof(MDRawContextARM));
+  context_ptr->context_flags = MD_CONTEXT_ARM_FULL;
+  context_ptr->iregs[7] = kExpectedFinalFp;  // FP
+  context_ptr->iregs[13] = kExpectedFinalSp;  // SP
+  uint32_t pc = GetPCFromException();
+  context_ptr->iregs[14] = pc;  // LR
+  context_ptr->iregs[15] = pc;  // PC
+  return true;
+#else
+  assert(false);
+  return false;
+#endif
+}
+
+uint32_t IosExceptionMinidumpGenerator::GetPCFromException() {
+  return [[return_addresses_ objectAtIndex:0] unsignedIntegerValue];
+}
+
+bool IosExceptionMinidumpGenerator::WriteExceptionStream(
+    MDRawDirectory *exception_stream) {
+#ifdef HAS_ARM_SUPPORT
+  TypedMDRVA<MDRawExceptionStream> exception(&writer_);
+
+  if (!exception.Allocate())
+    return false;
+
+  exception_stream->stream_type = MD_EXCEPTION_STREAM;
+  exception_stream->location = exception.location();
+  MDRawExceptionStream *exception_ptr = exception.get();
+  exception_ptr->thread_id = pthread_mach_thread_np(pthread_self());
+
+  // This naming is confusing, but it is the proper translation from
+  // mach naming to minidump naming.
+  exception_ptr->exception_record.exception_code = kExceptionType;
+  exception_ptr->exception_record.exception_flags = kExceptionCode;
+
+  if (!WriteCrashingContext(&exception_ptr->thread_context))
+    return false;
+
+  exception_ptr->exception_record.exception_address = GetPCFromException();
+  return true;
+#else
+  return MinidumpGenerator::WriteExceptionStream(exception_stream);
+#endif
+}
+
+bool IosExceptionMinidumpGenerator::WriteThreadStream(mach_port_t thread_id,
+                                                      MDRawThread *thread) {
+#ifdef HAS_ARM_SUPPORT
+  if (pthread_mach_thread_np(pthread_self()) != thread_id)
+    return MinidumpGenerator::WriteThreadStream(thread_id, thread);
+
+  size_t frame_count = [return_addresses_ count];
+  UntypedMDRVA memory(&writer_);
+  size_t size = 8 * (frame_count - 1) + 4;
+  if (!memory.Allocate(size))
+    return false;
+  scoped_array<uint8_t> stack_memory(new uint8_t[size]);
+  uint32_t sp = size - 4;
+  uint32_t fp = 0;
+  uint32_t lr = [[return_addresses_ lastObject] unsignedIntegerValue];
+  for (int current_frame = frame_count - 2;
+       current_frame >= 0;
+       --current_frame) {
+    AppendToMemory(stack_memory.get(), sp, fp);
+    sp -= 4;
+    fp = sp;
+    AppendToMemory(stack_memory.get(), sp, lr);
+    sp -= 4;
+    lr = [[return_addresses_ objectAtIndex:current_frame] unsignedIntegerValue];
+  }
+  if (!memory.Copy(stack_memory.get(), size))
+    return false;
+  assert(sp == kExpectedFinalSp);
+  assert(fp == kExpectedFinalFp);
+  assert(lr == GetPCFromException());
+  thread->stack.start_of_memory_range = sp;
+  thread->stack.memory = memory.location();
+  memory_blocks_.push_back(thread->stack);
+
+  if (!WriteCrashingContext(&thread->thread_context))
+    return false;
+
+  thread->thread_id = thread_id;
+  return true;
+#else
+  return MinidumpGenerator::WriteThreadStream(thread_id, thread);
+#endif
+}
+
+}  // namespace google_breakpad

src/client/mac/handler/minidump_generator.h

@@ -82,7 +82,7 @@ class MinidumpGenerator {
   MinidumpGenerator();
   MinidumpGenerator(mach_port_t crashing_task, mach_port_t handler_thread);
 
-  ~MinidumpGenerator();
+  virtual ~MinidumpGenerator();
 
   // Return <dir>/<unique_name>.dmp
   // Sets |unique_name| (if requested) to the unique name for the minidump
@@ -106,13 +106,19 @@ class MinidumpGenerator {
   // the MinidumpGenerator class.
   static void GatherSystemInformation();
 
+ protected:
+  // Overridable Stream writers
+  virtual bool WriteExceptionStream(MDRawDirectory *exception_stream);
+
+  // Overridable Helper
+  virtual bool WriteThreadStream(mach_port_t thread_id, MDRawThread *thread);
+
  private:
-    typedef bool (MinidumpGenerator::*WriteStreamFN)(MDRawDirectory *);
+  typedef bool (MinidumpGenerator::*WriteStreamFN)(MDRawDirectory *);
 
   // Stream writers
   bool WriteThreadListStream(MDRawDirectory *thread_list_stream);
   bool WriteMemoryListStream(MDRawDirectory *memory_list_stream);
-  bool WriteExceptionStream(MDRawDirectory *exception_stream);
   bool WriteSystemInfoStream(MDRawDirectory *system_info_stream);
   bool WriteModuleListStream(MDRawDirectory *module_list_stream);
   bool WriteMiscInfoStream(MDRawDirectory *misc_info_stream);
@@ -128,7 +134,6 @@ class MinidumpGenerator {
                   MDMemoryDescriptor *stack_location);
   bool WriteContext(breakpad_thread_state_data_t state,
                     MDLocationDescriptor *register_location);
-  bool WriteThreadStream(mach_port_t thread_id, MDRawThread *thread);
   bool WriteCVRecord(MDRawModule *module, int cpu_type,
                      const char *module_path, bool in_memory);
   bool WriteModuleStream(unsigned int index, MDRawModule *module);
@@ -172,9 +177,11 @@ class MinidumpGenerator {
   explicit MinidumpGenerator(const MinidumpGenerator &);
   void operator=(const MinidumpGenerator &);
 
+ protected:
   // Use this writer to put the data to disk
   MinidumpFileWriter writer_;
 
+ private:
   // Exception information
   int exception_type_;
   int exception_code_;
@@ -199,6 +206,7 @@ class MinidumpGenerator {
   // directly from the system, even while handling an exception.
   mutable PageAllocator allocator_;
 
+ protected:
   // Blocks of memory written to the dump. These are all currently
   // written while writing the thread list stream, but saved here
   // so a memory list stream can be written afterwards.