Add high level API for breakpad on iOS.

The new API allows to automatically upload repports to the crash server when the application restarts.

 This change also:
 - Correct a bug on the test for correct alignment of the abrt signal handler
 - Add user friendly information on crashes for SIGABRT and NSException
Review URL: https://breakpad.appspot.com/361001

git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@935 4c0a9323-5329-0410-9bdc-e9ce6186880e

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

@@ -52,6 +52,8 @@
 		16C7CE94147D4A4300776EAD /* md5.h in Headers */ = {isa = PBXBuildFile; fileRef = 16C7CCA5147D4A4300776EAD /* md5.h */; };
 		16C7CEA7147D4A4300776EAD /* string_conversion.cc in Sources */ = {isa = PBXBuildFile; fileRef = 16C7CCB9147D4A4300776EAD /* string_conversion.cc */; };
 		16C7CEA8147D4A4300776EAD /* string_conversion.h in Headers */ = {isa = PBXBuildFile; fileRef = 16C7CCBA147D4A4300776EAD /* string_conversion.h */; };
+		16C92FAD150DF8330053D7BA /* BreakpadController.h in Headers */ = {isa = PBXBuildFile; fileRef = 16C92FAB150DF8330053D7BA /* BreakpadController.h */; };
+		16C92FAE150DF8330053D7BA /* BreakpadController.mm in Sources */ = {isa = PBXBuildFile; fileRef = 16C92FAC150DF8330053D7BA /* BreakpadController.mm */; };
 		AA747D9F0F9514B9006C5449 /* Breakpad_Prefix.pch in Headers */ = {isa = PBXBuildFile; fileRef = AA747D9E0F9514B9006C5449 /* Breakpad_Prefix.pch */; };
 		AACBBE4A0F95108600F1A2B1 /* Foundation.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = AACBBE490F95108600F1A2B1 /* Foundation.framework */; };
 /* End PBXBuildFile section */
@@ -102,6 +104,8 @@
 		16C7CCA5147D4A4300776EAD /* md5.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = md5.h; sourceTree = "<group>"; };
 		16C7CCB9147D4A4300776EAD /* string_conversion.cc */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; path = string_conversion.cc; sourceTree = "<group>"; };
 		16C7CCBA147D4A4300776EAD /* string_conversion.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = string_conversion.h; sourceTree = "<group>"; };
+		16C92FAB150DF8330053D7BA /* BreakpadController.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = BreakpadController.h; sourceTree = "<group>"; };
+		16C92FAC150DF8330053D7BA /* BreakpadController.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; path = BreakpadController.mm; sourceTree = "<group>"; };
 		AA747D9E0F9514B9006C5449 /* Breakpad_Prefix.pch */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = Breakpad_Prefix.pch; sourceTree = SOURCE_ROOT; };
 		AACBBE490F95108600F1A2B1 /* Foundation.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = Foundation.framework; path = System/Library/Frameworks/Foundation.framework; sourceTree = SDKROOT; };
 		D2AAC07E0554694100DB518D /* libBreakpad.a */ = {isa = PBXFileReference; explicitFileType = archive.ar; includeInIndex = 0; path = libBreakpad.a; sourceTree = BUILT_PRODUCTS_DIR; };
@@ -198,6 +202,8 @@
 		16C7C969147D4A4200776EAD /* ios */ = {
 			isa = PBXGroup;
 			children = (
+				16C92FAB150DF8330053D7BA /* BreakpadController.h */,
+				16C92FAC150DF8330053D7BA /* BreakpadController.mm */,
 				16BFA66A14E195E9009704F8 /* handler */,
 				16C7C96A147D4A4200776EAD /* Breakpad.h */,
 				16C7C96B147D4A4200776EAD /* Breakpad.mm */,
@@ -327,6 +333,7 @@
 				16C7CE94147D4A4300776EAD /* md5.h in Headers */,
 				16C7CEA8147D4A4300776EAD /* string_conversion.h in Headers */,
 				16BFA67014E195E9009704F8 /* ios_exception_minidump_generator.h in Headers */,
+				16C92FAD150DF8330053D7BA /* BreakpadController.h in Headers */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};
@@ -413,6 +420,7 @@
 				16C7CE93147D4A4300776EAD /* md5.cc in Sources */,
 				16C7CEA7147D4A4300776EAD /* string_conversion.cc in Sources */,
 				16BFA67214E1965A009704F8 /* ios_exception_minidump_generator.mm in Sources */,
+				16C92FAE150DF8330053D7BA /* BreakpadController.mm in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};

src/client/ios/BreakpadController.h

@@ -0,0 +1,106 @@
+// 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.
+
+#ifndef CLIENT_IOS_HANDLER_IOS_BREAKPAD_CONTROLLER_H_
+#define CLIENT_IOS_HANDLER_IOS_BREAKPAD_CONTROLLER_H_
+
+#import <Foundation/Foundation.h>
+
+#import "client/ios/Breakpad.h"
+
+// This class is used to offer a higher level API around BreakpadRef. It
+// configures it, ensures thread-safety, and sends crash reports back to the
+// collecting server. By default, no crash reports are sent, the user must call
+// |setUploadingEnabled:YES| to start the uploading.
+@interface BreakpadController : NSObject {
+ @private
+  // The dispatch queue that will own the breakpad reference.
+  dispatch_queue_t queue_;
+
+  // Instance of Breakpad crash reporter. This is owned by the queue, but can
+  // be created on the main thread at startup.
+  BreakpadRef breakpadRef_;
+
+  // The dictionary that contains configuration for breakpad. Modifying it
+  // should only happen when the controller is not started. The initial value
+  // is the infoDictionary of the bundle of the application.
+  NSMutableDictionary* configuration_;
+
+  // Whether or not crash reports should be uploaded.
+  BOOL enableUploads_;
+
+  // The interval to wait between two uploads. Value is 0 if no upload must be
+  // done.
+  int uploadIntervalInSeconds_;
+}
+
+// Singleton.
++ (BreakpadController*)sharedInstance;
+
+// Update the controller configuration. Merges its old configuration with the
+// new one. Merge is done by replacing the old values by the new values.
+- (void)updateConfiguration:(NSDictionary*)configuration;
+
+// Configure the URL to upload the report to. This must be called at least once
+// if the URL is not in the bundle information.
+- (void)setUploadingURL:(NSString*)url;
+
+// Set the minimal interval between two uploads in seconds. This must be called
+// at least once if the interval is not in the bundle information. A value of 0
+// will prevent uploads.
+- (void)setUploadInterval:(int)intervalInSeconds;
+
+// Specify a parameter that will be uploaded to the crash server. See
+// |BreakpadAddUploadParameter|.
+- (void)addUploadParameter:(NSString*)value forKey:(NSString*)key;
+
+// Remove a previously-added parameter from the upload parameter set. See
+// |BreakpadRemoveUploadParameter|.
+- (void)removeUploadParameterForKey:(NSString*)key;
+
+// Access the underlying BreakpadRef. This method is asynchronous, and will be
+// executed on the thread owning the BreakpadRef variable. Moreover, if the
+// controller is not started, the block will be called with a NULL parameter.
+- (void)withBreakpadRef:(void(^)(BreakpadRef))callback;
+
+// Starts the BreakpadController by registering crash handlers. If
+// |onCurrentThread| is YES, all setup is done on the current thread, otherwise
+// it is done on a private queue.
+- (void)start:(BOOL)onCurrentThread;
+
+// Unregisters the crash handlers.
+- (void)stop;
+
+// Enables or disables uploading of crash reports, but does not stop the
+// BreakpadController.
+- (void)setUploadingEnabled:(BOOL)enabled;
+
+@end
+
+#endif  // CLIENT_IOS_HANDLER_IOS_BREAKPAD_CONTROLLER_H_

src/client/ios/BreakpadController.mm

@@ -0,0 +1,266 @@
+// 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.
+
+#import "BreakpadController.h"
+
+#import <UIKit/UIKit.h>
+#include <asl.h>
+#include <execinfo.h>
+#include <signal.h>
+#include <unistd.h>
+#include <sys/sysctl.h>
+
+#include <processor/scoped_ptr.h>
+
+#pragma mark -
+#pragma mark Private Methods
+
+@interface BreakpadController ()
+
+// Init the singleton instance.
+- (id)initSingleton;
+
+// Load a crash report and send it to the server.
+- (void)sendStoredCrashReports;
+
+// Returns when a report can be sent. |-1| means never, |0| means that a report
+// can be sent immediately, a positive number is the number of seconds to wait
+// before being allowed to upload a report.
+- (int)sendDelay;
+
+// Notifies that a report will be sent, and update the last sending time
+// accordingly.
+- (void)reportWillBeSent;
+
+@end
+
+#pragma mark -
+#pragma mark Anonymous namespace
+
+namespace {
+
+// The name of the user defaults key for the last submission to the crash
+// server.
+NSString* const kLastSubmission = @"com.google.Breakpad.LastSubmission";
+
+// Returns a NSString describing the current platform.
+NSString* GetPlatform() {
+  // Name of the system call for getting the platform.
+  static const char kHwMachineSysctlName[] = "hw.machine";
+
+  NSString* result = nil;
+
+  size_t size = 0;
+  if (sysctlbyname(kHwMachineSysctlName, NULL, &size, NULL, 0) || size == 0)
+    return nil;
+  google_breakpad::scoped_array<char> machine(new char[size]);
+  if (sysctlbyname(kHwMachineSysctlName, machine.get(), &size, NULL, 0) == 0)
+    result = [NSString stringWithUTF8String:machine.get()];
+  return result;
+}
+
+}  // namespace
+
+#pragma mark -
+#pragma mark BreakpadController Implementation
+
+@implementation BreakpadController
+
++ (BreakpadController*)sharedInstance {
+  @synchronized(self) {
+    static BreakpadController* sharedInstance_ =
+        [[BreakpadController alloc] initSingleton];
+    return sharedInstance_;
+  }
+}
+
+- (id)init {
+  return nil;
+}
+
+- (id)initSingleton {
+  self = [super init];
+  if (self) {
+    queue_ = dispatch_queue_create("com.google.BreakpadQueue", NULL);
+    configuration_ = [[[NSBundle mainBundle] infoDictionary] mutableCopy];
+    enableUploads_ = NO;
+    NSString* uploadInterval =
+        [configuration_ valueForKey:@BREAKPAD_REPORT_INTERVAL];
+    [self setUploadInterval:[uploadInterval intValue]];
+  }
+  return self;
+}
+
+// Since this class is a singleton, this method is not expected to be called.
+- (void)dealloc {
+  assert(!breakpadRef_);
+  dispatch_release(queue_);
+  [configuration_ release];
+  [super dealloc];
+}
+
+#pragma mark -
+
+- (void)start:(BOOL)onCurrentThread {
+  void(^startBlock)() = ^{
+      assert(!breakpadRef_);
+      breakpadRef_ = BreakpadCreate(configuration_);
+      if (breakpadRef_) {
+        BreakpadAddUploadParameter(breakpadRef_, @"platform", GetPlatform());
+      }
+  };
+  if (onCurrentThread)
+    startBlock();
+  else
+    dispatch_async(queue_, startBlock);
+}
+
+- (void)stop {
+  dispatch_sync(queue_, ^{
+      if (breakpadRef_) {
+        BreakpadRelease(breakpadRef_);
+        breakpadRef_ = NULL;
+      }
+  });
+}
+
+- (void)setUploadingEnabled:(BOOL)enabled {
+  dispatch_async(queue_, ^{
+      if (enabled == enableUploads_)
+        return;
+      if (enabled) {
+        // Set this before calling doSendStoredCrashReport, because that
+        // calls sendDelay, which in turn checks this flag.
+        enableUploads_ = YES;
+        [self sendStoredCrashReports];
+      } else {
+        enableUploads_ = NO;
+        [NSObject cancelPreviousPerformRequestsWithTarget:self
+            selector:@selector(sendStoredCrashReports)
+            object:nil];
+      }
+  });
+}
+
+- (void)updateConfiguration:(NSDictionary*)configuration {
+  [configuration_ addEntriesFromDictionary:configuration];
+  NSString* uploadInterval =
+      [configuration_ valueForKey:@BREAKPAD_REPORT_INTERVAL];
+  if (uploadInterval)
+    [self setUploadInterval:[uploadInterval intValue]];
+}
+
+- (void)setUploadingURL:(NSString*)url {
+  [configuration_ setValue:url forKey:@BREAKPAD_URL];
+}
+
+- (void)setUploadInterval:(int)intervalInSeconds {
+  [configuration_ removeObjectForKey:@BREAKPAD_REPORT_INTERVAL];
+  uploadIntervalInSeconds_ = intervalInSeconds;
+  if (uploadIntervalInSeconds_ < 0)
+    uploadIntervalInSeconds_ = 0;
+}
+
+- (void)addUploadParameter:(NSString*)value forKey:(NSString*)key {
+  dispatch_async(queue_, ^{
+      if (breakpadRef_)
+        BreakpadAddUploadParameter(breakpadRef_, key, value);
+  });
+}
+
+- (void)removeUploadParameterForKey:(NSString*)key {
+  dispatch_async(queue_, ^{
+      if (breakpadRef_)
+        BreakpadRemoveUploadParameter(breakpadRef_, key);
+  });
+}
+
+- (void)withBreakpadRef:(void(^)(BreakpadRef))callback {
+  dispatch_async(queue_, ^{
+      callback(breakpadRef_);
+  });
+}
+
+
+#pragma mark -
+
+- (int)sendDelay {
+  if (!breakpadRef_ || uploadIntervalInSeconds_ <= 0 || !enableUploads_)
+    return -1;
+
+  // To prevent overloading the crash server, crashes are not sent than one
+  // report every |uploadIntervalInSeconds_|. A value in the user defaults is
+  // used to keep the time of the last upload.
+  NSUserDefaults *userDefaults = [NSUserDefaults standardUserDefaults];
+  NSNumber *lastTimeNum = [userDefaults objectForKey:kLastSubmission];
+  NSTimeInterval lastTime = lastTimeNum ? [lastTimeNum floatValue] : 0;
+  NSTimeInterval spanSeconds = CFAbsoluteTimeGetCurrent() - lastTime;
+
+  if (spanSeconds >= uploadIntervalInSeconds_)
+    return 0;
+  return uploadIntervalInSeconds_ - spanSeconds;
+}
+
+- (void)reportWillBeSent {
+  NSUserDefaults *userDefaults = [NSUserDefaults standardUserDefaults];
+  [userDefaults setObject:[NSNumber numberWithDouble:CFAbsoluteTimeGetCurrent()]
+                   forKey:kLastSubmission];
+  [userDefaults synchronize];
+}
+
+- (void)sendStoredCrashReports {
+  dispatch_async(queue_, ^{
+      if (!BreakpadHasCrashReportToUpload(breakpadRef_))
+        return;
+
+      int timeToWait = [self sendDelay];
+
+      // Unable to ever send report.
+      if (timeToWait == -1)
+        return;
+
+      // A report can be sent now.
+      if (timeToWait == 0) {
+        [self reportWillBeSent];
+        BreakpadUploadNextReport(breakpadRef_);
+
+        // If more reports must be sent, make sure this method is called again.
+        if (BreakpadHasCrashReportToUpload(breakpadRef_))
+          timeToWait = uploadIntervalInSeconds_;
+      }
+
+      // A report must be sent later.
+      if (timeToWait > 0)
+        [self performSelector:@selector(sendStoredCrashReports)
+                   withObject:nil
+                   afterDelay:timeToWait];
+  });
+}
+
+@end

src/client/ios/handler/ios_exception_minidump_generator.mm

@@ -29,6 +29,7 @@
 
 #include "client/ios/handler/ios_exception_minidump_generator.h"
 
+#include "google_breakpad/common/minidump_exception_mac.h"
 #include "client/minidump_file_writer-inl.h"
 #include "processor/scoped_ptr.h"
 
@@ -37,7 +38,7 @@ namespace {
 const uint32_t kExpectedFinalFp = 4;
 const uint32_t kExpectedFinalSp = 0;
 const int kExceptionType = EXC_SOFTWARE;
-const int kExceptionCode = 0xDEADBEEF;
+const int kExceptionCode = MD_EXCEPTION_CODE_MAC_NS_EXCEPTION;
 
 // Append the given 4 bytes value to the sp position of the stack represented
 // by memory.

src/client/mac/handler/exception_handler.cc

@@ -38,6 +38,7 @@
 #include "client/mac/handler/minidump_generator.h"
 #include "common/mac/macho_utilities.h"
 #include "common/mac/scoped_task_suspend-inl.h"
+#include "google_breakpad/common/minidump_exception_mac.h"
 
 #ifndef USE_PROTECTED_ALLOCATIONS
 #if TARGET_OS_IPHONE
@@ -580,12 +581,13 @@ void *ExceptionHandler::WaitForMessage(void *exception_handler_class) {
 
 //static
 void ExceptionHandler::SignalHandler(int sig, siginfo_t* info, void* uc) {
-  gProtectedData.handler->WriteMinidumpWithException(EXC_CRASH,
-                                                     0xDEADBEEF,
-                                                     0,
-                                                     mach_thread_self(),
-                                                     true,
-                                                     true);
+  gProtectedData.handler->WriteMinidumpWithException(
+      EXC_SOFTWARE,
+      MD_EXCEPTION_CODE_MAC_ABORT,
+      0,
+      mach_thread_self(),
+      true,
+      true);
 }
 
 bool ExceptionHandler::InstallHandler() {
@@ -609,7 +611,7 @@ bool ExceptionHandler::InstallHandler() {
     old_handler_.swap(old);
     gProtectedData.handler = this;
 #if USE_PROTECTED_ALLOCATIONS
-    assert(((size_t)(*gProtectedData.protected_buffer) & PAGE_MASK) == 0);
+    assert(((size_t)(gProtectedData.protected_buffer) & PAGE_MASK) == 0);
     mprotect(gProtectedData.protected_buffer, PAGE_SIZE, PROT_READ);
 #endif
   }

src/google_breakpad/common/minidump_exception_mac.h

@@ -87,9 +87,11 @@ typedef enum {
       /* KERN_MEMORY_ERROR */
 
   /* With MD_EXCEPTION_SOFTWARE */
-  MD_EXCEPTION_CODE_MAC_BAD_SYSCALL = 0x00010000,  /* Mach SIGSYS */
-  MD_EXCEPTION_CODE_MAC_BAD_PIPE    = 0x00010001,  /* Mach SIGPIPE */
-  MD_EXCEPTION_CODE_MAC_ABORT       = 0x00010002,  /* Mach SIGABRT */
+  MD_EXCEPTION_CODE_MAC_BAD_SYSCALL  = 0x00010000,  /* Mach SIGSYS */
+  MD_EXCEPTION_CODE_MAC_BAD_PIPE     = 0x00010001,  /* Mach SIGPIPE */
+  MD_EXCEPTION_CODE_MAC_ABORT        = 0x00010002,  /* Mach SIGABRT */
+  /* Custom values */
+  MD_EXCEPTION_CODE_MAC_NS_EXCEPTION = 0xDEADC0DE,  /* uncaught NSException */
 
   /* With MD_EXCEPTION_MAC_BAD_ACCESS on ppc */
   MD_EXCEPTION_CODE_MAC_PPC_VM_PROT_READ = 0x0101,

src/processor/minidump_processor.cc

@@ -643,6 +643,12 @@ string MinidumpProcessor::GetCrashReason(Minidump *dump, u_int64_t *address) {
         case MD_EXCEPTION_MAC_SOFTWARE:
           reason = "EXC_SOFTWARE / ";
           switch (exception_flags) {
+            case MD_EXCEPTION_CODE_MAC_ABORT:
+              reason.append("SIGABRT");
+              break;
+            case MD_EXCEPTION_CODE_MAC_NS_EXCEPTION:
+              reason.append("UNCAUGHT_NS_EXCEPTION");
+              break;
             // These are ppc only but shouldn't be a problem as they're
             // unused on x86
             case MD_EXCEPTION_CODE_MAC_PPC_TRAP: