1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
5 #import "chrome/browser/chrome_browser_application_mac.h"
7 #include <objc/objc-exception.h>
9 #import "base/auto_reset.h"
10 #include "base/command_line.h"
11 #include "base/debug/crash_logging.h"
12 #include "base/debug/stack_trace.h"
13 #import "base/logging.h"
14 #include "base/mac/call_with_eh_frame.h"
15 #import "base/mac/scoped_nsobject.h"
16 #import "base/mac/scoped_objc_class_swizzler.h"
17 #import "base/metrics/histogram.h"
18 #include "base/profiler/scoped_tracker.h"
19 #include "base/strings/stringprintf.h"
20 #import "base/strings/sys_string_conversions.h"
21 #import "chrome/browser/app_controller_mac.h"
22 #include "chrome/browser/ui/tab_contents/tab_contents_iterator.h"
23 #include "chrome/common/chrome_switches.h"
24 #include "chrome/common/crash_keys.h"
25 #import "chrome/common/mac/objc_zombie.h"
26 #include "content/public/browser/browser_accessibility_state.h"
27 #include "content/public/browser/render_view_host.h"
28 #include "content/public/browser/web_contents.h"
30 namespace chrome_browser_application_mac {
32 // Maximum number of known named exceptions we'll support. There is
33 // no central registration, but I only find about 75 possibilities in
34 // the system frameworks, and many of them are probably not
35 // interesting to track in aggregate (those relating to distributed
36 // objects, for instance).
37 const size_t kKnownNSExceptionCount = 25;
39 const size_t kUnknownNSException = kKnownNSExceptionCount;
41 size_t BinForException(NSException* exception) {
42 // A list of common known exceptions. The list position will
43 // determine where they live in the histogram, so never move them
44 // around, only add to the end.
45 static NSString* const kKnownNSExceptionNames[] = {
46 // Grab-bag exception, not very common. CFArray (or other
47 // container) mutated while being enumerated is one case seen in
51 // Out-of-range on NSString or NSArray. Quite common.
54 // Invalid arg to method, unrecognized selector. Quite common.
55 NSInvalidArgumentException,
57 // malloc() returned null in object creation, I think. Turns out
58 // to be very uncommon in production, because of the OOM killer.
61 // This contains things like windowserver errors, trying to draw
62 // views which aren't in windows, unable to read nib files. By
63 // far the most common exception seen on the crash server.
64 NSInternalInconsistencyException,
69 // Make sure our array hasn't outgrown our abilities to track it.
70 DCHECK_LE(arraysize(kKnownNSExceptionNames), kKnownNSExceptionCount);
72 NSString* name = [exception name];
73 for (int i = 0; kKnownNSExceptionNames[i]; ++i) {
74 if (name == kKnownNSExceptionNames[i]) {
78 return kUnknownNSException;
81 void RecordExceptionWithUma(NSException* exception) {
82 UMA_HISTOGRAM_ENUMERATION("OSX.NSException",
83 BinForException(exception), kUnknownNSException);
88 objc_exception_preprocessor g_next_preprocessor = nullptr;
90 id ExceptionPreprocessor(id exception) {
91 static bool seen_first_exception = false;
93 RecordExceptionWithUma(exception);
95 const char* const kExceptionKey =
96 seen_first_exception ? crash_keys::mac::kLastNSException
97 : crash_keys::mac::kFirstNSException;
98 NSString* value = [NSString stringWithFormat:@"%@ reason %@",
99 [exception name], [exception reason]];
100 base::debug::SetCrashKeyValue(kExceptionKey, [value UTF8String]);
102 const char* const kExceptionTraceKey =
103 seen_first_exception ? crash_keys::mac::kLastNSExceptionTrace
104 : crash_keys::mac::kFirstNSExceptionTrace;
105 // This exception preprocessor runs prior to the one in libobjc, which sets
106 // the -[NSException callStackReturnAddresses].
107 base::debug::SetCrashKeyToStackTrace(kExceptionTraceKey,
108 base::debug::StackTrace());
110 seen_first_exception = true;
112 // Forward to the original version.
113 if (g_next_preprocessor)
114 return g_next_preprocessor(exception);
120 void RegisterBrowserCrApp() {
121 [BrowserCrApplication sharedApplication];
125 [NSApp terminate:nil];
128 void CancelTerminate() {
129 [NSApp cancelTerminate:nil];
132 } // namespace chrome_browser_application_mac
134 // These methods are being exposed for the purposes of overriding.
135 // Used to determine when a Panel window can become the key window.
136 @interface NSApplication (PanelsCanBecomeKey)
137 - (void)_cycleWindowsReversed:(BOOL)arg1;
138 - (id)_removeWindow:(NSWindow*)window;
139 - (id)_setKeyWindow:(NSWindow*)window;
142 @interface BrowserCrApplication (PrivateInternal)
144 // This must be called under the protection of previousKeyWindowsLock_.
145 - (void)removePreviousKeyWindow:(NSWindow*)window;
149 @implementation BrowserCrApplication
152 // Turn all deallocated Objective-C objects into zombies, keeping
153 // the most recent 10,000 of them on the treadmill.
154 ObjcEvilDoers::ZombieEnable(true, 10000);
156 if (!chrome_browser_application_mac::g_next_preprocessor) {
157 chrome_browser_application_mac::g_next_preprocessor =
158 objc_setExceptionPreprocessor(
159 &chrome_browser_application_mac::ExceptionPreprocessor);
166 // Sanity check to alert if overridden methods are not supported.
167 DCHECK([NSApplication
168 instancesRespondToSelector:@selector(_cycleWindowsReversed:)]);
169 DCHECK([NSApplication
170 instancesRespondToSelector:@selector(_removeWindow:)]);
171 DCHECK([NSApplication
172 instancesRespondToSelector:@selector(_setKeyWindow:)]);
177 // Initialize NSApplication using the custom subclass. Check whether NSApp
178 // was already initialized using another class, because that would break
180 + (NSApplication*)sharedApplication {
181 NSApplication* app = [super sharedApplication];
183 // +sharedApplication initializes the global NSApp, so if a specific
184 // NSApplication subclass is requested, require that to be the one
185 // delivered. The practical effect is to require a consistent NSApp
186 // across the executable.
187 CHECK([NSApp isKindOfClass:self])
188 << "NSApp must be of type " << [[self className] UTF8String]
189 << ", not " << [[NSApp className] UTF8String];
191 // If the message loop was initialized before NSApp is setup, the
192 // message pump will be setup incorrectly. Failing this implies
193 // that RegisterBrowserCrApp() should be called earlier.
194 CHECK(base::MessagePumpMac::UsingCrApp())
195 << "MessagePumpMac::Create() is using the wrong pump implementation"
196 << " for " << [[self className] UTF8String];
201 ////////////////////////////////////////////////////////////////////////////////
202 // HISTORICAL COMMENT (by viettrungluu, from
203 // http://codereview.chromium.org/1520006 with mild editing):
205 // A quick summary of the state of things (before the changes to shutdown):
207 // Currently, we are totally hosed (put in a bad state in which Cmd-W does the
208 // wrong thing, and which will probably eventually lead to a crash) if we begin
209 // quitting but termination is aborted for some reason.
211 // I currently know of two ways in which termination can be aborted:
212 // (1) Common case: a window has an onbeforeunload handler which pops up a
213 // "leave web page" dialog, and the user answers "no, don't leave".
214 // (2) Uncommon case: popups are enabled (in Content Settings, i.e., the popup
215 // blocker is disabled), and some nasty web page pops up a new window on
218 // I don't know of other ways in which termination can be aborted, but they may
219 // exist (or may be added in the future, for that matter).
221 // My CL [see above] does the following:
222 // a. Should prevent being put in a bad state (which breaks Cmd-W and leads to
223 // crash) under all circumstances.
224 // b. Should completely handle (1) properly.
225 // c. Doesn't (yet) handle (2) properly and puts it in a weird state (but not
227 // d. Any other ways of aborting termination would put it in that weird state.
229 // c. can be fixed by having the global flag reset on browser creation or
230 // similar (and doing so might also fix some possible d.'s as well). I haven't
231 // done this yet since I haven't thought about it carefully and since it's a
234 // The weird state: a state in which closing the last window quits the browser.
235 // This might be a bit annoying, but it's not dangerous in any way.
236 ////////////////////////////////////////////////////////////////////////////////
238 // |-terminate:| is the entry point for orderly "quit" operations in Cocoa. This
239 // includes the application menu's quit menu item and keyboard equivalent, the
240 // application's dock icon menu's quit menu item, "quit" (not "force quit") in
241 // the Activity Monitor, and quits triggered by user logout and system restart
244 // The default |-terminate:| implementation ends the process by calling exit(),
245 // and thus never leaves the main run loop. This is unsuitable for Chrome since
246 // Chrome depends on leaving the main run loop to perform an orderly shutdown.
247 // We support the normal |-terminate:| interface by overriding the default
248 // implementation. Our implementation, which is very specific to the needs of
249 // Chrome, works by asking the application delegate to terminate using its
250 // |-tryToTerminateApplication:| method.
252 // |-tryToTerminateApplication:| differs from the standard
253 // |-applicationShouldTerminate:| in that no special event loop is run in the
254 // case that immediate termination is not possible (e.g., if dialog boxes
255 // allowing the user to cancel have to be shown). Instead, this method sets a
256 // flag and tries to close all browsers. This flag causes the closure of the
257 // final browser window to begin actual tear-down of the application.
258 // Termination is cancelled by resetting this flag. The standard
259 // |-applicationShouldTerminate:| is not supported, and code paths leading to it
260 // must be redirected.
262 // When the last browser has been destroyed, the BrowserList calls
263 // chrome::OnAppExiting(), which is the point of no return. That will cause
264 // the NSApplicationWillTerminateNotification to be posted, which ends the
265 // NSApplication event loop, so final post- MessageLoop::Run() work is done
267 - (void)terminate:(id)sender {
268 AppController* appController = static_cast<AppController*>([NSApp delegate]);
269 [appController tryToTerminateApplication:self];
270 // Return, don't exit. The application is responsible for exiting on its own.
273 - (void)cancelTerminate:(id)sender {
274 AppController* appController = static_cast<AppController*>([NSApp delegate]);
275 [appController stopTryingToTerminateApplication:self];
278 - (BOOL)sendAction:(SEL)anAction to:(id)aTarget from:(id)sender {
279 // The Dock menu contains an automagic section where you can select
280 // amongst open windows. If a window is closed via JavaScript while
281 // the menu is up, the menu item for that window continues to exist.
282 // When a window is selected this method is called with the
283 // now-freed window as |aTarget|. Short-circuit the call if
284 // |aTarget| is not a valid window.
285 if (anAction == @selector(_selectWindow:)) {
286 // Not using -[NSArray containsObject:] because |aTarget| may be a
289 for (NSWindow* window in [self windows]) {
290 if (window == aTarget) {
300 // When a Cocoa control is wired to a freed object, we get crashers
301 // in the call to |super| with no useful information in the
302 // backtrace. Attempt to add some useful information.
304 // If the action is something generic like -commandDispatch:, then
305 // the tag is essential.
307 if ([sender isKindOfClass:[NSControl class]]) {
309 if (tag == 0 || tag == -1) {
310 tag = [sender selectedTag];
312 } else if ([sender isKindOfClass:[NSMenuItem class]]) {
316 NSString* actionString = NSStringFromSelector(anAction);
317 std::string value = base::StringPrintf("%s tag %ld sending %s to %p",
318 [[sender className] UTF8String],
319 static_cast<long>(tag),
320 [actionString UTF8String],
322 base::debug::ScopedCrashKey key(crash_keys::mac::kSendAction, value);
324 return [super sendAction:anAction to:aTarget from:sender];
327 - (BOOL)isHandlingSendEvent {
328 return handlingSendEvent_;
331 - (void)setHandlingSendEvent:(BOOL)handlingSendEvent {
332 handlingSendEvent_ = handlingSendEvent;
335 - (void)sendEvent:(NSEvent*)event {
336 base::mac::CallWithEHFrame(^{
337 // tracked_objects::ScopedTracker does not support parameterized
338 // instrumentations, so a big switch with each bunch instrumented is
340 switch (event.type) {
341 case NSLeftMouseDown:
342 case NSRightMouseDown: {
343 // In kiosk mode, we want to prevent context menus from appearing,
344 // so simply discard menu-generating events instead of passing them
346 bool kioskMode = base::CommandLine::ForCurrentProcess()->HasSwitch(
347 switches::kKioskMode);
348 bool ctrlDown = [event modifierFlags] & NSControlKeyMask;
349 if (kioskMode && ([event type] == NSRightMouseDown || ctrlDown))
356 case NSLeftMouseDragged:
357 case NSRightMouseDragged:
360 case NSOtherMouseDown:
362 case NSOtherMouseDragged: {
363 tracked_objects::ScopedTracker tracking_profile(
364 FROM_HERE_WITH_EXPLICIT_FUNCTION(
365 "463272 -[BrowserCrApplication sendEvent:] Mouse"));
366 base::mac::ScopedSendingEvent sendingEventScoper;
367 [super sendEvent:event];
373 tracked_objects::ScopedTracker tracking_profile(
374 FROM_HERE_WITH_EXPLICIT_FUNCTION(
375 "463272 -[BrowserCrApplication sendEvent:] Key"));
376 base::mac::ScopedSendingEvent sendingEventScoper;
377 [super sendEvent:event];
381 case NSScrollWheel: {
382 tracked_objects::ScopedTracker tracking_profile(
383 FROM_HERE_WITH_EXPLICIT_FUNCTION(
384 "463272 -[BrowserCrApplication sendEvent:] ScrollWheel"));
385 base::mac::ScopedSendingEvent sendingEventScoper;
386 [super sendEvent:event];
390 case NSEventTypeGesture:
391 case NSEventTypeMagnify:
392 case NSEventTypeSwipe:
393 case NSEventTypeRotate:
394 case NSEventTypeBeginGesture:
395 case NSEventTypeEndGesture: {
396 tracked_objects::ScopedTracker tracking_profile(
397 FROM_HERE_WITH_EXPLICIT_FUNCTION(
398 "463272 -[BrowserCrApplication sendEvent:] Gesture"));
399 base::mac::ScopedSendingEvent sendingEventScoper;
400 [super sendEvent:event];
404 case NSAppKitDefined: {
405 tracked_objects::ScopedTracker tracking_profile(
406 FROM_HERE_WITH_EXPLICIT_FUNCTION(
407 "463272 -[BrowserCrApplication sendEvent:] AppKit"));
408 base::mac::ScopedSendingEvent sendingEventScoper;
409 [super sendEvent:event];
413 case NSSystemDefined: {
414 tracked_objects::ScopedTracker tracking_profile(
415 FROM_HERE_WITH_EXPLICIT_FUNCTION(
416 "463272 -[BrowserCrApplication sendEvent:] System"));
417 base::mac::ScopedSendingEvent sendingEventScoper;
418 [super sendEvent:event];
423 tracked_objects::ScopedTracker tracking_profile(
424 FROM_HERE_WITH_EXPLICIT_FUNCTION(
425 "463272 -[BrowserCrApplication sendEvent:] Other"));
426 base::mac::ScopedSendingEvent sendingEventScoper;
427 [super sendEvent:event];
433 - (void)accessibilitySetValue:(id)value forAttribute:(NSString*)attribute {
434 // This is an undocument attribute that's set when VoiceOver is turned on/off.
435 if ([attribute isEqualToString:@"AXEnhancedUserInterface"]) {
436 content::BrowserAccessibilityState* accessibility_state =
437 content::BrowserAccessibilityState::GetInstance();
438 if ([value intValue] == 1)
439 accessibility_state->OnScreenReaderDetected();
441 accessibility_state->DisableAccessibility();
443 return [super accessibilitySetValue:value forAttribute:attribute];
446 - (void)_cycleWindowsReversed:(BOOL)arg1 {
447 base::AutoReset<BOOL> pin(&cyclingWindows_, YES);
448 [super _cycleWindowsReversed:arg1];
451 - (BOOL)isCyclingWindows {
452 return cyclingWindows_;
455 - (id)_removeWindow:(NSWindow*)window {
456 // Note _removeWindow is called from -[NSWindow dealloc], which can happen at
457 // unpredictable times due to reference counting. Just update state.
459 base::AutoLock lock(previousKeyWindowsLock_);
460 [self removePreviousKeyWindow:window];
462 return [super _removeWindow:window];
465 - (id)_setKeyWindow:(NSWindow*)window {
466 // |window| is nil when the current key window is being closed.
467 // A separate call follows with a new value when a new key window is set.
468 // Closed windows are not tracked in previousKeyWindows_.
470 base::AutoLock lock(previousKeyWindowsLock_);
471 [self removePreviousKeyWindow:window];
472 NSWindow* currentKeyWindow = [self keyWindow];
473 if (currentKeyWindow != nil && currentKeyWindow != window)
474 previousKeyWindows_.push_back(currentKeyWindow);
477 return [super _setKeyWindow:window];
480 - (NSWindow*)previousKeyWindow {
481 base::AutoLock lock(previousKeyWindowsLock_);
482 return previousKeyWindows_.empty() ? nil : previousKeyWindows_.back();
485 - (void)removePreviousKeyWindow:(NSWindow*)window {
486 previousKeyWindowsLock_.AssertAcquired();
487 std::vector<NSWindow*>::iterator window_iterator =
488 std::find(previousKeyWindows_.begin(),
489 previousKeyWindows_.end(),
491 if (window_iterator != previousKeyWindows_.end()) {
492 previousKeyWindows_.erase(window_iterator);