libdispatch-913.30.4.tar.gz

[apple/libdispatch.git] / src / init.c

diff --git a/src/init.c b/src/init.c
index d72219c92247d13a1cbec11e0c6c78b7b004e338..6672fac45dbbb2fb37391bfd420e832ce6bcf14c 100644 (file)
--- a/src/init.c
+++ b/src/init.c
@@ -1,5 +1,5 @@
 /*
 /*

- * Copyright (c) 2008-2011 Apple Inc. All rights reserved.
+ * Copyright (c) 2008-2013 Apple Inc. All rights reserved.

  *
  * @APPLE_APACHE_LICENSE_HEADER_START@
  *
  *
  * @APPLE_APACHE_LICENSE_HEADER_START@
  *


@@ -21,6 +21,8 @@
 // Contains exported global data and initialization & other routines that must
 // only exist once in the shared library even when resolvers are used.
 
 // Contains exported global data and initialization & other routines that must
 // only exist once in the shared library even when resolvers are used.
 

+// NOTE: this file must not contain any atomic operations
+

 #include "internal.h"
 
 #if HAVE_MACH
 #include "internal.h"
 
 #if HAVE_MACH


@@ -47,147 +49,608 @@ DISPATCH_EXPORT DISPATCH_NOTHROW
 void
 dispatch_atfork_prepare(void)
 {
 void
 dispatch_atfork_prepare(void)
 {

+       _os_object_atfork_prepare();

 }
 
 DISPATCH_EXPORT DISPATCH_NOTHROW
 void
 dispatch_atfork_parent(void)
 {
 }
 
 DISPATCH_EXPORT DISPATCH_NOTHROW
 void
 dispatch_atfork_parent(void)
 {

+       _os_object_atfork_parent();

 }
 
 }
 

+DISPATCH_EXPORT DISPATCH_NOTHROW

 void
 void

-dummy_function(void)
+dispatch_atfork_child(void)

 {
 {

+       _os_object_atfork_child();
+       _voucher_atfork_child();
+       _dispatch_event_loop_atfork_child();
+       if (_dispatch_is_multithreaded_inline()) {
+               _dispatch_child_of_unsafe_fork = true;
+       }
+       _dispatch_queue_atfork_child();
+       // clear the _PROHIBIT and _MULTITHREADED bits if set
+       _dispatch_unsafe_fork = 0;

 }
 
 }
 

-long
-dummy_function_r0(void)
+int
+_dispatch_sigmask(void)

 {
 {

-       return 0;
+       sigset_t mask;
+       int r = 0;
+
+       /* Workaround: 6269619 Not all signals can be delivered on any thread */
+       r |= sigfillset(&mask);
+       r |= sigdelset(&mask, SIGILL);
+       r |= sigdelset(&mask, SIGTRAP);
+#if HAVE_DECL_SIGEMT
+       r |= sigdelset(&mask, SIGEMT);
+#endif
+       r |= sigdelset(&mask, SIGFPE);
+       r |= sigdelset(&mask, SIGBUS);
+       r |= sigdelset(&mask, SIGSEGV);
+       r |= sigdelset(&mask, SIGSYS);
+       r |= sigdelset(&mask, SIGPIPE);
+       r |= sigdelset(&mask, SIGPROF);
+       r |= pthread_sigmask(SIG_BLOCK, &mask, NULL);
+       return dispatch_assume_zero(r);

 }
 
 #pragma mark -
 #pragma mark dispatch_globals
 
 }
 
 #pragma mark -
 #pragma mark dispatch_globals
 

+DISPATCH_HIDE_SYMBOL(dispatch_assert_queue, 10.12, 10.0, 10.0, 3.0);
+DISPATCH_HIDE_SYMBOL(dispatch_assert_queue_not, 10.12, 10.0, 10.0, 3.0);
+DISPATCH_HIDE_SYMBOL(dispatch_queue_create_with_target, 10.12, 10.0, 10.0, 3.0);
+

 #if DISPATCH_COCOA_COMPAT
 #if DISPATCH_COCOA_COMPAT

-// dispatch_begin_thread_4GC having non-default value triggers GC-only slow
-// paths and is checked frequently, testing against NULL is faster than
-// comparing for equality with "dummy_function"
-void (*dispatch_begin_thread_4GC)(void) = NULL;
-void (*dispatch_end_thread_4GC)(void) = dummy_function;
-void (*dispatch_no_worker_threads_4GC)(void) = NULL;
-void *(*_dispatch_begin_NSAutoReleasePool)(void) = (void *)dummy_function;
-void (*_dispatch_end_NSAutoReleasePool)(void *) = (void *)dummy_function;
+void *(*_dispatch_begin_NSAutoReleasePool)(void);
+void (*_dispatch_end_NSAutoReleasePool)(void *);

 #endif
 
 #endif
 

-struct _dispatch_hw_config_s _dispatch_hw_config;
-bool _dispatch_safe_fork = true;
+#if DISPATCH_USE_THREAD_LOCAL_STORAGE
+__thread struct dispatch_tsd __dispatch_tsd;
+pthread_key_t __dispatch_tsd_key;
+#elif !DISPATCH_USE_DIRECT_TSD
+pthread_key_t dispatch_queue_key;
+pthread_key_t dispatch_frame_key;
+pthread_key_t dispatch_cache_key;
+pthread_key_t dispatch_context_key;
+pthread_key_t dispatch_pthread_root_queue_observer_hooks_key;
+pthread_key_t dispatch_basepri_key;
+#if DISPATCH_INTROSPECTION
+pthread_key_t dispatch_introspection_key;
+#elif DISPATCH_PERF_MON
+pthread_key_t dispatch_bcounter_key;
+#endif
+pthread_key_t dispatch_wlh_key;
+pthread_key_t dispatch_voucher_key;
+pthread_key_t dispatch_deferred_items_key;
+#endif // !DISPATCH_USE_DIRECT_TSD && !DISPATCH_USE_THREAD_LOCAL_STORAGE
+
+#if VOUCHER_USE_MACH_VOUCHER
+dispatch_once_t _voucher_task_mach_voucher_pred;
+mach_voucher_t _voucher_task_mach_voucher;
+#if !VOUCHER_USE_EMPTY_MACH_BASE_VOUCHER
+mach_voucher_t _voucher_default_task_mach_voucher;
+#endif
+dispatch_once_t _firehose_task_buffer_pred;
+firehose_buffer_t _firehose_task_buffer;
+const uint32_t _firehose_spi_version = OS_FIREHOSE_SPI_VERSION;
+uint64_t _voucher_unique_pid;
+voucher_activity_hooks_t _voucher_libtrace_hooks;
+dispatch_mach_t _voucher_activity_debug_channel;
+#endif
+#if HAVE_PTHREAD_WORKQUEUE_QOS && DISPATCH_DEBUG
+int _dispatch_set_qos_class_enabled;
+#endif
+#if DISPATCH_USE_KEVENT_WORKQUEUE && DISPATCH_USE_MGR_THREAD
+int _dispatch_kevent_workqueue_enabled;
+#endif
+
+DISPATCH_HW_CONFIG();
+uint8_t _dispatch_unsafe_fork;
+bool _dispatch_child_of_unsafe_fork;
+#if DISPATCH_USE_MEMORYPRESSURE_SOURCE
+bool _dispatch_memory_warn;
+int _dispatch_continuation_cache_limit = DISPATCH_CONTINUATION_CACHE_LIMIT;
+#endif
+
+DISPATCH_NOINLINE
+bool
+_dispatch_is_multithreaded(void)
+{
+       return _dispatch_is_multithreaded_inline();
+}
+
+DISPATCH_NOINLINE
+bool
+_dispatch_is_fork_of_multithreaded_parent(void)
+{
+       return _dispatch_child_of_unsafe_fork;
+}

 
 const struct dispatch_queue_offsets_s dispatch_queue_offsets = {
 
 const struct dispatch_queue_offsets_s dispatch_queue_offsets = {

-       .dqo_version = 3,
+       .dqo_version = 6,

        .dqo_label = offsetof(struct dispatch_queue_s, dq_label),
        .dqo_label_size = sizeof(((dispatch_queue_t)NULL)->dq_label),
        .dqo_flags = 0,
        .dqo_flags_size = 0,
        .dqo_label = offsetof(struct dispatch_queue_s, dq_label),
        .dqo_label_size = sizeof(((dispatch_queue_t)NULL)->dq_label),
        .dqo_flags = 0,
        .dqo_flags_size = 0,

-       .dqo_width = offsetof(struct dispatch_queue_s, dq_width),
-       .dqo_width_size = sizeof(((dispatch_queue_t)NULL)->dq_width),

        .dqo_serialnum = offsetof(struct dispatch_queue_s, dq_serialnum),
        .dqo_serialnum_size = sizeof(((dispatch_queue_t)NULL)->dq_serialnum),
        .dqo_serialnum = offsetof(struct dispatch_queue_s, dq_serialnum),
        .dqo_serialnum_size = sizeof(((dispatch_queue_t)NULL)->dq_serialnum),

-       .dqo_running = offsetof(struct dispatch_queue_s, dq_running),
-       .dqo_running_size = sizeof(((dispatch_queue_t)NULL)->dq_running),
+       .dqo_width = offsetof(struct dispatch_queue_s, dq_width),
+       .dqo_width_size = sizeof(((dispatch_queue_t)NULL)->dq_width),
+       .dqo_running = 0,
+       .dqo_running_size = 0,
+       .dqo_suspend_cnt = 0,
+       .dqo_suspend_cnt_size = 0,
+       .dqo_target_queue = offsetof(struct dispatch_queue_s, do_targetq),
+       .dqo_target_queue_size = sizeof(((dispatch_queue_t)NULL)->do_targetq),
+       .dqo_priority = 0,
+       .dqo_priority_size = 0,
+};
+
+#if DISPATCH_USE_DIRECT_TSD
+const struct dispatch_tsd_indexes_s dispatch_tsd_indexes = {
+       .dti_version = 2,
+       .dti_queue_index = dispatch_queue_key,
+       .dti_voucher_index = dispatch_voucher_key,
+       .dti_qos_class_index = dispatch_priority_key,

 };
 };

+#endif // DISPATCH_USE_DIRECT_TSD

 
 // 6618342 Contact the team that owns the Instrument DTrace probe before
 //         renaming this symbol
 DISPATCH_CACHELINE_ALIGN
 struct dispatch_queue_s _dispatch_main_q = {
 
 // 6618342 Contact the team that owns the Instrument DTrace probe before
 //         renaming this symbol
 DISPATCH_CACHELINE_ALIGN
 struct dispatch_queue_s _dispatch_main_q = {

+       DISPATCH_GLOBAL_OBJECT_HEADER(queue_main),

 #if !DISPATCH_USE_RESOLVERS
 #if !DISPATCH_USE_RESOLVERS

-       .do_vtable = &_dispatch_queue_vtable,

        .do_targetq = &_dispatch_root_queues[
        .do_targetq = &_dispatch_root_queues[

-                       DISPATCH_ROOT_QUEUE_IDX_DEFAULT_OVERCOMMIT_PRIORITY],
+                       DISPATCH_ROOT_QUEUE_IDX_DEFAULT_QOS_OVERCOMMIT],

 #endif
 #endif

-       .do_ref_cnt = DISPATCH_OBJECT_GLOBAL_REFCNT,
-       .do_xref_cnt = DISPATCH_OBJECT_GLOBAL_REFCNT,
-       .do_suspend_cnt = DISPATCH_OBJECT_SUSPEND_LOCK,
+       .dq_state = DISPATCH_QUEUE_STATE_INIT_VALUE(1) |
+                       DISPATCH_QUEUE_ROLE_BASE_ANON,

        .dq_label = "com.apple.main-thread",
        .dq_label = "com.apple.main-thread",

-       .dq_running = 1,
-       .dq_width = 1,
+       .dq_atomic_flags = DQF_THREAD_BOUND | DQF_CANNOT_TRYSYNC | DQF_WIDTH(1),

        .dq_serialnum = 1,
 };
 
        .dq_serialnum = 1,
 };
 

-const struct dispatch_queue_attr_vtable_s dispatch_queue_attr_vtable = {
+#pragma mark -
+#pragma mark dispatch_queue_attr_t
+
+#define DISPATCH_QUEUE_ATTR_INIT(qos, prio, overcommit, freq, concurrent, \
+                       inactive) \
+       { \
+               DISPATCH_GLOBAL_OBJECT_HEADER(queue_attr), \
+               .dqa_qos_and_relpri = (_dispatch_priority_make(qos, prio) & \
+                               DISPATCH_PRIORITY_REQUESTED_MASK), \
+               .dqa_overcommit = _dispatch_queue_attr_overcommit_##overcommit, \
+               .dqa_autorelease_frequency = DISPATCH_AUTORELEASE_FREQUENCY_##freq, \
+               .dqa_concurrent = (concurrent), \
+               .dqa_inactive = (inactive), \
+       }
+
+#define DISPATCH_QUEUE_ATTR_ACTIVE_INIT(qos, prio, overcommit, freq, \
+                       concurrent) \
+       { \
+               [DQA_INDEX_ACTIVE] = DISPATCH_QUEUE_ATTR_INIT( \
+                               qos, prio, overcommit, freq, concurrent, false), \
+               [DQA_INDEX_INACTIVE] = DISPATCH_QUEUE_ATTR_INIT( \
+                               qos, prio, overcommit, freq, concurrent, true), \
+       }
+
+#define DISPATCH_QUEUE_ATTR_OVERCOMMIT_INIT(qos, prio, overcommit) \
+       { \
+               [DQA_INDEX_AUTORELEASE_FREQUENCY_INHERIT][DQA_INDEX_CONCURRENT] = \
+                               DISPATCH_QUEUE_ATTR_ACTIVE_INIT( \
+                                               qos, prio, overcommit, INHERIT, 1), \
+               [DQA_INDEX_AUTORELEASE_FREQUENCY_INHERIT][DQA_INDEX_SERIAL] = \
+                               DISPATCH_QUEUE_ATTR_ACTIVE_INIT( \
+                                               qos, prio, overcommit, INHERIT, 0), \
+               [DQA_INDEX_AUTORELEASE_FREQUENCY_WORK_ITEM][DQA_INDEX_CONCURRENT] = \
+                               DISPATCH_QUEUE_ATTR_ACTIVE_INIT( \
+                                               qos, prio, overcommit, WORK_ITEM, 1), \
+               [DQA_INDEX_AUTORELEASE_FREQUENCY_WORK_ITEM][DQA_INDEX_SERIAL] = \
+                               DISPATCH_QUEUE_ATTR_ACTIVE_INIT( \
+                                               qos, prio, overcommit, WORK_ITEM, 0), \
+               [DQA_INDEX_AUTORELEASE_FREQUENCY_NEVER][DQA_INDEX_CONCURRENT] = \
+                               DISPATCH_QUEUE_ATTR_ACTIVE_INIT( \
+                                               qos, prio, overcommit, NEVER, 1), \
+               [DQA_INDEX_AUTORELEASE_FREQUENCY_NEVER][DQA_INDEX_SERIAL] = \
+                               DISPATCH_QUEUE_ATTR_ACTIVE_INIT(\
+                                               qos, prio, overcommit, NEVER, 0), \
+       }
+
+#define DISPATCH_QUEUE_ATTR_PRIO_INITIALIZER(qos, prio) \
+       [prio] = { \
+               [DQA_INDEX_UNSPECIFIED_OVERCOMMIT] = \
+                               DISPATCH_QUEUE_ATTR_OVERCOMMIT_INIT(qos, -(prio), unspecified),\
+               [DQA_INDEX_NON_OVERCOMMIT] = \
+                               DISPATCH_QUEUE_ATTR_OVERCOMMIT_INIT(qos, -(prio), disabled), \
+               [DQA_INDEX_OVERCOMMIT] = \
+                               DISPATCH_QUEUE_ATTR_OVERCOMMIT_INIT(qos, -(prio), enabled), \
+       }
+
+#define DISPATCH_QUEUE_ATTR_PRIO_INIT(qos) \
+       { \
+               DISPATCH_QUEUE_ATTR_PRIO_INITIALIZER(qos, 0), \
+               DISPATCH_QUEUE_ATTR_PRIO_INITIALIZER(qos, 1), \
+               DISPATCH_QUEUE_ATTR_PRIO_INITIALIZER(qos, 2), \
+               DISPATCH_QUEUE_ATTR_PRIO_INITIALIZER(qos, 3), \
+               DISPATCH_QUEUE_ATTR_PRIO_INITIALIZER(qos, 4), \
+               DISPATCH_QUEUE_ATTR_PRIO_INITIALIZER(qos, 5), \
+               DISPATCH_QUEUE_ATTR_PRIO_INITIALIZER(qos, 6), \
+               DISPATCH_QUEUE_ATTR_PRIO_INITIALIZER(qos, 7), \
+               DISPATCH_QUEUE_ATTR_PRIO_INITIALIZER(qos, 8), \
+               DISPATCH_QUEUE_ATTR_PRIO_INITIALIZER(qos, 9), \
+               DISPATCH_QUEUE_ATTR_PRIO_INITIALIZER(qos, 10), \
+               DISPATCH_QUEUE_ATTR_PRIO_INITIALIZER(qos, 11), \
+               DISPATCH_QUEUE_ATTR_PRIO_INITIALIZER(qos, 12), \
+               DISPATCH_QUEUE_ATTR_PRIO_INITIALIZER(qos, 13), \
+               DISPATCH_QUEUE_ATTR_PRIO_INITIALIZER(qos, 14), \
+               DISPATCH_QUEUE_ATTR_PRIO_INITIALIZER(qos, 15), \
+       }
+
+#define DISPATCH_QUEUE_ATTR_QOS_INITIALIZER(qos) \
+       [DQA_INDEX_QOS_CLASS_##qos] = \
+                       DISPATCH_QUEUE_ATTR_PRIO_INIT(DISPATCH_QOS_##qos)
+
+// DISPATCH_QUEUE_CONCURRENT resp. _dispatch_queue_attr_concurrent is aliased
+// to array member [0][0][0][0][0][0] and their properties must match!
+const struct dispatch_queue_attr_s _dispatch_queue_attrs[]
+               [DISPATCH_QUEUE_ATTR_PRIO_COUNT]
+               [DISPATCH_QUEUE_ATTR_OVERCOMMIT_COUNT]
+               [DISPATCH_QUEUE_ATTR_AUTORELEASE_FREQUENCY_COUNT]
+               [DISPATCH_QUEUE_ATTR_CONCURRENCY_COUNT]
+               [DISPATCH_QUEUE_ATTR_INACTIVE_COUNT] = {
+       DISPATCH_QUEUE_ATTR_QOS_INITIALIZER(UNSPECIFIED),
+       DISPATCH_QUEUE_ATTR_QOS_INITIALIZER(MAINTENANCE),
+       DISPATCH_QUEUE_ATTR_QOS_INITIALIZER(BACKGROUND),
+       DISPATCH_QUEUE_ATTR_QOS_INITIALIZER(UTILITY),
+       DISPATCH_QUEUE_ATTR_QOS_INITIALIZER(DEFAULT),
+       DISPATCH_QUEUE_ATTR_QOS_INITIALIZER(USER_INITIATED),
+       DISPATCH_QUEUE_ATTR_QOS_INITIALIZER(USER_INTERACTIVE),
+};
+
+#if DISPATCH_VARIANT_STATIC
+// <rdar://problem/16778703>
+struct dispatch_queue_attr_s _dispatch_queue_attr_concurrent =
+       DISPATCH_QUEUE_ATTR_INIT(QOS_CLASS_UNSPECIFIED, 0,
+                       unspecified, INHERIT, 1, false);
+#endif // DISPATCH_VARIANT_STATIC
+
+// _dispatch_queue_attr_concurrent is aliased using libdispatch.aliases
+// and the -alias_list linker option on Darwin but needs to be done manually
+// for other platforms.
+#ifndef __APPLE__
+extern struct dispatch_queue_attr_s _dispatch_queue_attr_concurrent
+       __attribute__((__alias__("_dispatch_queue_attrs")));
+#endif
+
+#pragma mark -
+#pragma mark dispatch_vtables
+
+DISPATCH_VTABLE_INSTANCE(semaphore,
+       .do_type = DISPATCH_SEMAPHORE_TYPE,
+       .do_kind = "semaphore",
+       .do_dispose = _dispatch_semaphore_dispose,
+       .do_debug = _dispatch_semaphore_debug,
+);
+
+DISPATCH_VTABLE_INSTANCE(group,
+       .do_type = DISPATCH_GROUP_TYPE,
+       .do_kind = "group",
+       .do_dispose = _dispatch_group_dispose,
+       .do_debug = _dispatch_group_debug,
+);
+
+DISPATCH_VTABLE_INSTANCE(queue,
+       .do_type = DISPATCH_QUEUE_LEGACY_TYPE,
+       .do_kind = "queue",
+       .do_dispose = _dispatch_queue_dispose,
+       .do_suspend = _dispatch_queue_suspend,
+       .do_resume = _dispatch_queue_resume,
+       .do_push = _dispatch_queue_push,
+       .do_invoke = _dispatch_queue_invoke,
+       .do_wakeup = _dispatch_queue_wakeup,
+       .do_debug = dispatch_queue_debug,
+       .do_set_targetq = _dispatch_queue_set_target_queue,
+);
+
+DISPATCH_VTABLE_SUBCLASS_INSTANCE(queue_serial, queue,
+       .do_type = DISPATCH_QUEUE_SERIAL_TYPE,
+       .do_kind = "serial-queue",
+       .do_dispose = _dispatch_queue_dispose,
+       .do_suspend = _dispatch_queue_suspend,
+       .do_resume = _dispatch_queue_resume,
+       .do_finalize_activation = _dispatch_queue_finalize_activation,
+       .do_push = _dispatch_queue_push,
+       .do_invoke = _dispatch_queue_invoke,
+       .do_wakeup = _dispatch_queue_wakeup,
+       .do_debug = dispatch_queue_debug,
+       .do_set_targetq = _dispatch_queue_set_target_queue,
+);
+
+DISPATCH_VTABLE_SUBCLASS_INSTANCE(queue_concurrent, queue,
+       .do_type = DISPATCH_QUEUE_CONCURRENT_TYPE,
+       .do_kind = "concurrent-queue",
+       .do_dispose = _dispatch_queue_dispose,
+       .do_suspend = _dispatch_queue_suspend,
+       .do_resume = _dispatch_queue_resume,
+       .do_finalize_activation = _dispatch_queue_finalize_activation,
+       .do_push = _dispatch_queue_push,
+       .do_invoke = _dispatch_queue_invoke,
+       .do_wakeup = _dispatch_queue_wakeup,
+       .do_debug = dispatch_queue_debug,
+       .do_set_targetq = _dispatch_queue_set_target_queue,
+);
+
+
+DISPATCH_VTABLE_SUBCLASS_INSTANCE(queue_root, queue,
+       .do_type = DISPATCH_QUEUE_GLOBAL_ROOT_TYPE,
+       .do_kind = "global-queue",
+       .do_dispose = _dispatch_pthread_root_queue_dispose,
+       .do_push = _dispatch_root_queue_push,
+       .do_invoke = NULL,
+       .do_wakeup = _dispatch_root_queue_wakeup,
+       .do_debug = dispatch_queue_debug,
+);
+
+
+DISPATCH_VTABLE_SUBCLASS_INSTANCE(queue_main, queue,
+       .do_type = DISPATCH_QUEUE_SERIAL_TYPE,
+       .do_kind = "main-queue",
+       .do_dispose = _dispatch_queue_dispose,
+       .do_push = _dispatch_queue_push,
+       .do_invoke = _dispatch_queue_invoke,
+       .do_wakeup = _dispatch_main_queue_wakeup,
+       .do_debug = dispatch_queue_debug,
+);
+
+DISPATCH_VTABLE_SUBCLASS_INSTANCE(queue_runloop, queue,
+       .do_type = DISPATCH_QUEUE_RUNLOOP_TYPE,
+       .do_kind = "runloop-queue",
+       .do_dispose = _dispatch_runloop_queue_dispose,
+       .do_push = _dispatch_queue_push,
+       .do_invoke = _dispatch_queue_invoke,
+       .do_wakeup = _dispatch_runloop_queue_wakeup,
+       .do_debug = dispatch_queue_debug,
+);
+
+DISPATCH_VTABLE_SUBCLASS_INSTANCE(queue_mgr, queue,
+       .do_type = DISPATCH_QUEUE_MGR_TYPE,
+       .do_kind = "mgr-queue",
+       .do_push = _dispatch_mgr_queue_push,
+       .do_invoke = _dispatch_mgr_thread,
+       .do_wakeup = _dispatch_mgr_queue_wakeup,
+       .do_debug = dispatch_queue_debug,
+);
+
+DISPATCH_VTABLE_INSTANCE(queue_specific_queue,
+       .do_type = DISPATCH_QUEUE_SPECIFIC_TYPE,
+       .do_kind = "queue-context",
+       .do_dispose = _dispatch_queue_specific_queue_dispose,
+       .do_push = (void *)_dispatch_queue_push,
+       .do_invoke = (void *)_dispatch_queue_invoke,
+       .do_wakeup = (void *)_dispatch_queue_wakeup,
+       .do_debug = (void *)dispatch_queue_debug,
+);
+
+DISPATCH_VTABLE_INSTANCE(queue_attr,

        .do_type = DISPATCH_QUEUE_ATTR_TYPE,
        .do_kind = "queue-attr",
        .do_type = DISPATCH_QUEUE_ATTR_TYPE,
        .do_kind = "queue-attr",

+);
+
+DISPATCH_VTABLE_INSTANCE(source,
+       .do_type = DISPATCH_SOURCE_KEVENT_TYPE,
+       .do_kind = "kevent-source",
+       .do_dispose = _dispatch_source_dispose,
+       .do_suspend = (void *)_dispatch_queue_suspend,
+       .do_resume = (void *)_dispatch_queue_resume,
+       .do_finalize_activation = _dispatch_source_finalize_activation,
+       .do_push = (void *)_dispatch_queue_push,
+       .do_invoke = _dispatch_source_invoke,
+       .do_wakeup = _dispatch_source_wakeup,
+       .do_debug = _dispatch_source_debug,
+       .do_set_targetq = (void *)_dispatch_queue_set_target_queue,
+);
+
+#if HAVE_MACH
+DISPATCH_VTABLE_INSTANCE(mach,
+       .do_type = DISPATCH_MACH_CHANNEL_TYPE,
+       .do_kind = "mach-channel",
+       .do_dispose = _dispatch_mach_dispose,
+       .do_suspend = (void *)_dispatch_queue_suspend,
+       .do_resume = (void *)_dispatch_queue_resume,
+       .do_finalize_activation = _dispatch_mach_finalize_activation,
+       .do_push = (void *)_dispatch_queue_push,
+       .do_invoke = _dispatch_mach_invoke,
+       .do_wakeup = _dispatch_mach_wakeup,
+       .do_debug = _dispatch_mach_debug,
+       .do_set_targetq = (void *)_dispatch_queue_set_target_queue,
+);
+
+DISPATCH_VTABLE_INSTANCE(mach_msg,
+       .do_type = DISPATCH_MACH_MSG_TYPE,
+       .do_kind = "mach-msg",
+       .do_dispose = _dispatch_mach_msg_dispose,
+       .do_invoke = _dispatch_mach_msg_invoke,
+       .do_debug = _dispatch_mach_msg_debug,
+);
+#endif // HAVE_MACH
+
+#if !DISPATCH_DATA_IS_BRIDGED_TO_NSDATA
+DISPATCH_VTABLE_INSTANCE(data,
+       .do_type = DISPATCH_DATA_TYPE,
+       .do_kind = "data",
+       .do_dispose = _dispatch_data_dispose,
+       .do_debug = _dispatch_data_debug,
+       .do_set_targetq = (void*)_dispatch_data_set_target_queue,
+);
+#endif
+
+DISPATCH_VTABLE_INSTANCE(io,
+       .do_type = DISPATCH_IO_TYPE,
+       .do_kind = "channel",
+       .do_dispose = _dispatch_io_dispose,
+       .do_debug = _dispatch_io_debug,
+       .do_set_targetq = _dispatch_io_set_target_queue,
+);
+
+DISPATCH_VTABLE_INSTANCE(operation,
+       .do_type = DISPATCH_OPERATION_TYPE,
+       .do_kind = "operation",
+       .do_dispose = _dispatch_operation_dispose,
+       .do_debug = _dispatch_operation_debug,
+);
+
+DISPATCH_VTABLE_INSTANCE(disk,
+       .do_type = DISPATCH_DISK_TYPE,
+       .do_kind = "disk",
+       .do_dispose = _dispatch_disk_dispose,
+);
+
+
+void
+_dispatch_vtable_init(void)
+{
+#if OS_OBJECT_HAVE_OBJC2
+       // ObjC classes and dispatch vtables are co-located via linker order and
+       // alias files, verify correct layout during initialization rdar://10640168
+       dispatch_assert((char*)&DISPATCH_CONCAT(_,DISPATCH_CLASS(semaphore_vtable))
+                       - (char*)DISPATCH_VTABLE(semaphore) ==
+                       offsetof(struct dispatch_semaphore_vtable_s, _os_obj_vtable));
+#endif // USE_OBJC
+}
+
+#pragma mark -
+#pragma mark dispatch_data globals
+
+const dispatch_block_t _dispatch_data_destructor_free = ^{
+       DISPATCH_INTERNAL_CRASH(0, "free destructor called");

 };
 
 };
 

-struct dispatch_queue_attr_s _dispatch_queue_attr_concurrent = {
-       .do_vtable = &dispatch_queue_attr_vtable,
-       .do_ref_cnt = DISPATCH_OBJECT_GLOBAL_REFCNT,
-       .do_xref_cnt = DISPATCH_OBJECT_GLOBAL_REFCNT,
-       .do_next = DISPATCH_OBJECT_LISTLESS,
+const dispatch_block_t _dispatch_data_destructor_none = ^{
+       DISPATCH_INTERNAL_CRASH(0, "none destructor called");

 };
 
 };
 

-struct dispatch_data_s _dispatch_data_empty = {
-#if !DISPATCH_USE_RESOLVERS
-       .do_vtable = &_dispatch_data_vtable,
+#if !HAVE_MACH
+const dispatch_block_t _dispatch_data_destructor_munmap = ^{
+       DISPATCH_INTERNAL_CRASH(0, "munmap destructor called");
+};
+#else
+// _dispatch_data_destructor_munmap is a linker alias to the following
+const dispatch_block_t _dispatch_data_destructor_vm_deallocate = ^{
+       DISPATCH_INTERNAL_CRASH(0, "vmdeallocate destructor called");
+};

 #endif
 #endif

-       .do_ref_cnt = DISPATCH_OBJECT_GLOBAL_REFCNT,
-       .do_xref_cnt = DISPATCH_OBJECT_GLOBAL_REFCNT,
-       .do_next = DISPATCH_OBJECT_LISTLESS,
+
+const dispatch_block_t _dispatch_data_destructor_inline = ^{
+       DISPATCH_INTERNAL_CRASH(0, "inline destructor called");

 };
 
 };
 

-const dispatch_block_t _dispatch_data_destructor_free = ^{
-       DISPATCH_CRASH("free destructor called");
+struct dispatch_data_s _dispatch_data_empty = {
+#if DISPATCH_DATA_IS_BRIDGED_TO_NSDATA
+       .do_vtable = DISPATCH_DATA_EMPTY_CLASS,
+#else
+       DISPATCH_GLOBAL_OBJECT_HEADER(data),
+       .do_next = DISPATCH_OBJECT_LISTLESS,
+#endif

 };
 
 #pragma mark -
 };
 
 #pragma mark -

-#pragma mark dispatch_log
+#pragma mark dispatch_bug

 
 static char _dispatch_build[16];
 
 static void
 
 static char _dispatch_build[16];
 
 static void

-_dispatch_bug_init(void *context DISPATCH_UNUSED)
+_dispatch_build_init(void *context DISPATCH_UNUSED)

 {
 #ifdef __APPLE__
        int mib[] = { CTL_KERN, KERN_OSVERSION };
        size_t bufsz = sizeof(_dispatch_build);
 
        sysctl(mib, 2, _dispatch_build, &bufsz, NULL, 0);
 {
 #ifdef __APPLE__
        int mib[] = { CTL_KERN, KERN_OSVERSION };
        size_t bufsz = sizeof(_dispatch_build);
 
        sysctl(mib, 2, _dispatch_build, &bufsz, NULL, 0);

+#if TARGET_IPHONE_SIMULATOR
+       char *sim_version = getenv("SIMULATOR_RUNTIME_BUILD_VERSION");
+       if (sim_version) {
+               (void)strlcat(_dispatch_build, " ", sizeof(_dispatch_build));
+               (void)strlcat(_dispatch_build, sim_version, sizeof(_dispatch_build));
+       }
+#endif // TARGET_IPHONE_SIMULATOR
+

 #else
        /*
         * XXXRW: What to do here for !Mac OS X?
         */
        memset(_dispatch_build, 0, sizeof(_dispatch_build));
 #else
        /*
         * XXXRW: What to do here for !Mac OS X?
         */
        memset(_dispatch_build, 0, sizeof(_dispatch_build));

-#endif
+#endif // __APPLE__
+}
+
+static dispatch_once_t _dispatch_build_pred;
+
+char*
+_dispatch_get_build(void)
+{
+       dispatch_once_f(&_dispatch_build_pred, NULL, _dispatch_build_init);
+       return _dispatch_build;

 }
 
 }
 

+#define _dispatch_bug_log(msg, ...) do { \
+       static void *last_seen; \
+       void *ra = __builtin_return_address(0); \
+       if (last_seen != ra) { \
+               last_seen = ra; \
+               _dispatch_log(msg, ##__VA_ARGS__); \
+       } \
+} while(0)
+

 void
 _dispatch_bug(size_t line, long val)
 {
 void
 _dispatch_bug(size_t line, long val)
 {

-       static dispatch_once_t pred;
-       static void *last_seen;
-       void *ra = __builtin_return_address(0);
+       dispatch_once_f(&_dispatch_build_pred, NULL, _dispatch_build_init);
+       _dispatch_bug_log("BUG in libdispatch: %s - %lu - 0x%lx",
+                       _dispatch_build, (unsigned long)line, val);
+}

 
 

-       dispatch_once_f(&pred, NULL, _dispatch_bug_init);
-       if (last_seen != ra) {
-               last_seen = ra;
-               _dispatch_log("BUG in libdispatch: %s - %lu - 0x%lx",
-                               _dispatch_build, (unsigned long)line, val);
-       }
+void
+_dispatch_bug_client(const char* msg)
+{
+       _dispatch_bug_log("BUG in libdispatch client: %s", msg);

 }
 
 }
 

+#if HAVE_MACH

 void
 _dispatch_bug_mach_client(const char* msg, mach_msg_return_t kr)
 {
 void
 _dispatch_bug_mach_client(const char* msg, mach_msg_return_t kr)
 {

-       static void *last_seen;
-       void *ra = __builtin_return_address(0);
-       if (last_seen != ra) {
-               last_seen = ra;
-               _dispatch_log("BUG in libdispatch client: %s %s - 0x%x", msg,
-                               mach_error_string(kr), kr);
+       _dispatch_bug_log("BUG in libdispatch client: %s %s - 0x%x", msg,
+                       mach_error_string(kr), kr);
+}
+#endif
+
+void
+_dispatch_bug_kevent_client(const char* msg, const char* filter,
+               const char *operation, int err)
+{
+       if (operation && err) {
+               _dispatch_bug_log("BUG in libdispatch client: %s[%s] %s: \"%s\" - 0x%x",
+                               msg, filter, operation, strerror(err), err);
+       } else if (operation) {
+               _dispatch_bug_log("BUG in libdispatch client: %s[%s] %s",
+                               msg, filter, operation);
+       } else {
+               _dispatch_bug_log("BUG in libdispatch: %s[%s]: \"%s\" - 0x%x",
+                               msg, filter, strerror(err), err);

        }
 }
 
        }
 }
 

+void
+_dispatch_bug_deprecated(const char *msg)
+{
+       _dispatch_bug_log("DEPRECATED USE in libdispatch client: %s", msg);
+}
+

 void
 _dispatch_abort(size_t line, long val)
 {
 void
 _dispatch_abort(size_t line, long val)
 {


@@ -195,18 +658,17 @@ _dispatch_abort(size_t line, long val)
        abort();
 }
 
        abort();
 }
 

-void
-_dispatch_log(const char *msg, ...)
-{
-       va_list ap;
+#if !DISPATCH_USE_OS_DEBUG_LOG

 
 

-       va_start(ap, msg);
-       _dispatch_logv(msg, ap);
-       va_end(ap);
-}
+#pragma mark -
+#pragma mark dispatch_log

 
 

-static FILE *dispatch_logfile;
+static int dispatch_logfile = -1;

 static bool dispatch_log_disabled;
 static bool dispatch_log_disabled;

+#if DISPATCH_DEBUG
+static uint64_t dispatch_log_basetime;
+#endif
+static dispatch_once_t _dispatch_logv_pred;

 
 static void
 _dispatch_logv_init(void *context DISPATCH_UNUSED)
 
 static void
 _dispatch_logv_init(void *context DISPATCH_UNUSED)


@@ -228,73 +690,246 @@ _dispatch_logv_init(void *context DISPATCH_UNUSED)
                        log_to_file = true;
                } else if (strcmp(e, "stderr") == 0) {
                        log_to_file = true;
                        log_to_file = true;
                } else if (strcmp(e, "stderr") == 0) {
                        log_to_file = true;

-                       dispatch_logfile = stderr;
+                       dispatch_logfile = STDERR_FILENO;

                }
        }
        if (!dispatch_log_disabled) {
                }
        }
        if (!dispatch_log_disabled) {

-               if (log_to_file && !dispatch_logfile) {
+               if (log_to_file && dispatch_logfile == -1) {

                        char path[PATH_MAX];
                        snprintf(path, sizeof(path), "/var/tmp/libdispatch.%d.log",
                                        getpid());
                        char path[PATH_MAX];
                        snprintf(path, sizeof(path), "/var/tmp/libdispatch.%d.log",
                                        getpid());

-                       dispatch_logfile = fopen(path, "a");
+                       dispatch_logfile = open(path, O_WRONLY | O_APPEND | O_CREAT |
+                                       O_NOFOLLOW | O_CLOEXEC, 0666);

                }
                }

-               if (dispatch_logfile) {
+               if (dispatch_logfile != -1) {

                        struct timeval tv;
                        gettimeofday(&tv, NULL);
                        struct timeval tv;
                        gettimeofday(&tv, NULL);

-                       fprintf(dispatch_logfile, "=== log file opened for %s[%u] at "
+#if DISPATCH_DEBUG
+                       dispatch_log_basetime = _dispatch_absolute_time();
+#endif
+                       dprintf(dispatch_logfile, "=== log file opened for %s[%u] at "

                                        "%ld.%06u ===\n", getprogname() ?: "", getpid(),
                                        "%ld.%06u ===\n", getprogname() ?: "", getpid(),

-                                       tv.tv_sec, tv.tv_usec);
-                       fflush(dispatch_logfile);
+                                       tv.tv_sec, (int)tv.tv_usec);

                }
        }
 }
 
                }
        }
 }
 

-void
-_dispatch_logv(const char *msg, va_list ap)
+static inline void
+_dispatch_log_file(char *buf, size_t len)

 {
 {

-       static dispatch_once_t pred;
-       dispatch_once_f(&pred, NULL, _dispatch_logv_init);
+       ssize_t r;
+
+       buf[len++] = '\n';
+retry:
+       r = write(dispatch_logfile, buf, len);
+       if (slowpath(r == -1) && errno == EINTR) {
+               goto retry;
+       }
+}

 
 

+DISPATCH_NOINLINE
+static void
+_dispatch_logv_file(const char *msg, va_list ap)
+{
+       char buf[2048];
+       size_t bufsiz = sizeof(buf), offset = 0;
+       int r;
+
+#if DISPATCH_DEBUG
+       offset += dsnprintf(&buf[offset], bufsiz - offset, "%llu\t",
+                       _dispatch_absolute_time() - dispatch_log_basetime);
+#endif
+       r = vsnprintf(&buf[offset], bufsiz - offset, msg, ap);
+       if (r < 0) return;
+       offset += (size_t)r;
+       if (offset > bufsiz - 1) {
+               offset = bufsiz - 1;
+       }
+       _dispatch_log_file(buf, offset);
+}
+
+#if DISPATCH_USE_SIMPLE_ASL
+static inline void
+_dispatch_syslog(const char *msg)
+{
+       _simple_asl_log(ASL_LEVEL_NOTICE, "com.apple.libsystem.libdispatch", msg);
+}
+
+static inline void
+_dispatch_vsyslog(const char *msg, va_list ap)
+{
+       char *str;
+    vasprintf(&str, msg, ap);
+       if (str) {
+               _dispatch_syslog(str);
+               free(str);
+       }
+}
+#else // DISPATCH_USE_SIMPLE_ASL
+static inline void
+_dispatch_syslog(const char *msg)
+{
+       syslog(LOG_NOTICE, "%s", msg);
+}
+
+static inline void
+_dispatch_vsyslog(const char *msg, va_list ap)
+{
+       vsyslog(LOG_NOTICE, msg, ap);
+}
+#endif // DISPATCH_USE_SIMPLE_ASL
+
+DISPATCH_ALWAYS_INLINE
+static inline void
+_dispatch_logv(const char *msg, size_t len, va_list *ap_ptr)
+{
+       dispatch_once_f(&_dispatch_logv_pred, NULL, _dispatch_logv_init);

        if (slowpath(dispatch_log_disabled)) {
                return;
        }
        if (slowpath(dispatch_log_disabled)) {
                return;
        }

-       if (slowpath(dispatch_logfile)) {
-               vfprintf(dispatch_logfile, msg, ap);
-               // TODO: May cause interleaving with another thread's log
-               fputc('\n', dispatch_logfile);
-               fflush(dispatch_logfile);
-               return;
+       if (slowpath(dispatch_logfile != -1)) {
+               if (!ap_ptr) {
+                       return _dispatch_log_file((char*)msg, len);
+               }
+               return _dispatch_logv_file(msg, *ap_ptr);

        }
        }

-       vsyslog(LOG_NOTICE, msg, ap);
+       if (!ap_ptr) {
+               return _dispatch_syslog(msg);
+       }
+       return _dispatch_vsyslog(msg, *ap_ptr);
+}
+
+DISPATCH_NOINLINE
+void
+_dispatch_log(const char *msg, ...)
+{
+       va_list ap;
+
+       va_start(ap, msg);
+       _dispatch_logv(msg, 0, &ap);
+       va_end(ap);

 }
 
 }
 

+#endif // DISPATCH_USE_OS_DEBUG_LOG
+

 #pragma mark -
 #pragma mark dispatch_debug
 
 #pragma mark -
 #pragma mark dispatch_debug
 

+static size_t
+_dispatch_object_debug2(dispatch_object_t dou, char* buf, size_t bufsiz)
+{
+       DISPATCH_OBJECT_TFB(_dispatch_objc_debug, dou, buf, bufsiz);
+       if (dx_vtable(dou._do)->do_debug) {
+               return dx_debug(dou._do, buf, bufsiz);
+       }
+       return strlcpy(buf, "NULL vtable slot: ", bufsiz);
+}
+
+DISPATCH_NOINLINE
+static void
+_dispatch_debugv(dispatch_object_t dou, const char *msg, va_list ap)
+{
+       char buf[2048];
+       size_t bufsiz = sizeof(buf), offset = 0;
+       int r;
+#if DISPATCH_DEBUG && !DISPATCH_USE_OS_DEBUG_LOG
+       offset += dsnprintf(&buf[offset], bufsiz - offset, "%llu\t\t%p\t",
+                       _dispatch_absolute_time() - dispatch_log_basetime,
+                       (void *)_dispatch_thread_self());
+#endif
+       if (dou._do) {
+               offset += _dispatch_object_debug2(dou, &buf[offset], bufsiz - offset);
+               dispatch_assert(offset + 2 < bufsiz);
+               buf[offset++] = ':';
+               buf[offset++] = ' ';
+               buf[offset]   = '\0';
+       } else {
+               offset += strlcpy(&buf[offset], "NULL: ", bufsiz - offset);
+       }
+       r = vsnprintf(&buf[offset], bufsiz - offset, msg, ap);
+#if !DISPATCH_USE_OS_DEBUG_LOG
+       size_t len = offset + (r < 0 ? 0 : (size_t)r);
+       if (len > bufsiz - 1) {
+               len = bufsiz - 1;
+       }
+       _dispatch_logv(buf, len, NULL);
+#else
+       _dispatch_log("%s", buf);
+#endif
+}
+
+DISPATCH_NOINLINE
+void
+dispatch_debugv(dispatch_object_t dou, const char *msg, va_list ap)
+{
+       _dispatch_debugv(dou, msg, ap);
+}
+
+DISPATCH_NOINLINE

 void
 dispatch_debug(dispatch_object_t dou, const char *msg, ...)
 {
        va_list ap;
 
        va_start(ap, msg);
 void
 dispatch_debug(dispatch_object_t dou, const char *msg, ...)
 {
        va_list ap;
 
        va_start(ap, msg);

-       dispatch_debugv(dou._do, msg, ap);
+       _dispatch_debugv(dou, msg, ap);

        va_end(ap);
 }
 
        va_end(ap);
 }
 

+#if DISPATCH_DEBUG
+DISPATCH_NOINLINE

 void
 void

-dispatch_debugv(dispatch_object_t dou, const char *msg, va_list ap)
+_dispatch_object_debug(dispatch_object_t dou, const char *msg, ...)

 {
 {

-       char buf[4096];
-       size_t offs;
+       va_list ap;

 
 

-       if (dou._do && dou._do->do_vtable->do_debug) {
-               offs = dx_debug(dou._do, buf, sizeof(buf));
-       } else {
-               offs = snprintf(buf, sizeof(buf), "NULL vtable slot");
+       va_start(ap, msg);
+       _dispatch_debugv(dou._do, msg, ap);
+       va_end(ap);
+}
+#endif
+
+#pragma mark -
+#pragma mark dispatch_calloc
+
+DISPATCH_NOINLINE
+void
+_dispatch_temporary_resource_shortage(void)
+{
+       sleep(1);
+       asm("");  // prevent tailcall
+}
+
+void *
+_dispatch_calloc(size_t num_items, size_t size)
+{
+       void *buf;
+       while (!fastpath(buf = calloc(num_items, size))) {
+               _dispatch_temporary_resource_shortage();

        }
        }

+       return buf;
+}

 
 

-       snprintf(buf + offs, sizeof(buf) - offs, ": %s", msg);
-       _dispatch_logv(buf, ap);
+/**
+ * If the source string is mutable, allocates memory and copies the contents.
+ * Otherwise returns the source string.
+ */
+const char *
+_dispatch_strdup_if_mutable(const char *str)
+{
+#if HAVE_DYLD_IS_MEMORY_IMMUTABLE
+       size_t size = strlen(str) + 1;
+       if (slowpath(!_dyld_is_memory_immutable(str, size))) {
+               char *clone = (char *) malloc(size);
+               if (dispatch_assume(clone)) {
+                       memcpy(clone, str, size);
+               }
+               return clone;
+       }
+       return str;
+#else
+       return strdup(str);
+#endif

 }
 
 #pragma mark -
 }
 
 #pragma mark -


@@ -302,16 +937,18 @@ dispatch_debugv(dispatch_object_t dou, const char *msg, va_list ap)
 
 #ifdef __BLOCKS__
 
 
 #ifdef __BLOCKS__
 

-#undef _dispatch_Block_copy
-dispatch_block_t
-_dispatch_Block_copy(dispatch_block_t db)
+void *
+(_dispatch_Block_copy)(void *db)

 {
        dispatch_block_t rval;
 
 {
        dispatch_block_t rval;
 

-       while (!(rval = Block_copy(db))) {
-               sleep(1);
+       if (fastpath(db)) {
+               while (!fastpath(rval = Block_copy(db))) {
+                       _dispatch_temporary_resource_shortage();
+               }
+               return rval;

        }
        }

-       return rval;
+       DISPATCH_CLIENT_CRASH(0, "NULL was passed where a block should have been");

 }
 
 void
 }
 
 void


@@ -327,233 +964,217 @@ _dispatch_call_block_and_release(void *block)
 #pragma mark -
 #pragma mark dispatch_client_callout
 
 #pragma mark -
 #pragma mark dispatch_client_callout
 

-#if DISPATCH_USE_CLIENT_CALLOUT
+// Abort on uncaught exceptions thrown from client callouts rdar://8577499
+#if DISPATCH_USE_CLIENT_CALLOUT && (__USING_SJLJ_EXCEPTIONS__ || !USE_OBJC || \
+               OS_OBJECT_HAVE_OBJC1)
+// On platforms with SjLj exceptions, avoid the SjLj overhead on every callout
+// by clearing the unwinder's TSD pointer to the handler stack around callouts

 
 

-#undef _dispatch_client_callout
-#undef _dispatch_client_callout2
+#define _dispatch_get_tsd_base()
+#define _dispatch_get_unwind_tsd() (NULL)
+#define _dispatch_set_unwind_tsd(u) do {(void)(u);} while (0)
+#define _dispatch_free_unwind_tsd()

 
 

+#undef _dispatch_client_callout

 DISPATCH_NOINLINE
 void
 _dispatch_client_callout(void *ctxt, dispatch_function_t f)
 {
 DISPATCH_NOINLINE
 void
 _dispatch_client_callout(void *ctxt, dispatch_function_t f)
 {

-       return f(ctxt);
+       _dispatch_get_tsd_base();
+       void *u = _dispatch_get_unwind_tsd();
+       if (fastpath(!u)) return f(ctxt);
+       _dispatch_set_unwind_tsd(NULL);
+       f(ctxt);
+       _dispatch_free_unwind_tsd();
+       _dispatch_set_unwind_tsd(u);

 }
 
 }
 

+#undef _dispatch_client_callout2

 DISPATCH_NOINLINE
 void
 _dispatch_client_callout2(void *ctxt, size_t i, void (*f)(void *, size_t))
 {
 DISPATCH_NOINLINE
 void
 _dispatch_client_callout2(void *ctxt, size_t i, void (*f)(void *, size_t))
 {

-       return f(ctxt, i);
+       _dispatch_get_tsd_base();
+       void *u = _dispatch_get_unwind_tsd();
+       if (fastpath(!u)) return f(ctxt, i);
+       _dispatch_set_unwind_tsd(NULL);
+       f(ctxt, i);
+       _dispatch_free_unwind_tsd();
+       _dispatch_set_unwind_tsd(u);

 }
 
 }
 

-#endif
+#if HAVE_MACH
+
+#undef _dispatch_client_callout3
+DISPATCH_NOINLINE
+void
+_dispatch_client_callout3(void *ctxt, dispatch_mach_reason_t reason,
+               dispatch_mach_msg_t dmsg, dispatch_mach_async_reply_callback_t f)
+{
+       _dispatch_get_tsd_base();
+       void *u = _dispatch_get_unwind_tsd();
+       if (fastpath(!u)) return f(ctxt, reason, dmsg);
+       _dispatch_set_unwind_tsd(NULL);
+       f(ctxt, reason, dmsg);
+       _dispatch_free_unwind_tsd();
+       _dispatch_set_unwind_tsd(u);
+}
+
+#undef _dispatch_client_callout4
+void
+_dispatch_client_callout4(void *ctxt, dispatch_mach_reason_t reason,
+               dispatch_mach_msg_t dmsg, mach_error_t error,
+               dispatch_mach_handler_function_t f)
+{
+       _dispatch_get_tsd_base();
+       void *u = _dispatch_get_unwind_tsd();
+       if (fastpath(!u)) return f(ctxt, reason, dmsg, error);
+       _dispatch_set_unwind_tsd(NULL);
+       f(ctxt, reason, dmsg, error);
+       _dispatch_free_unwind_tsd();
+       _dispatch_set_unwind_tsd(u);
+}
+#endif // HAVE_MACH
+
+#endif // DISPATCH_USE_CLIENT_CALLOUT

 
 #pragma mark -
 
 #pragma mark -

-#pragma mark dispatch_source_types
+#pragma mark _os_object_t no_objc

 
 

-static void
-dispatch_source_type_timer_init(dispatch_source_t ds,
-       dispatch_source_type_t type DISPATCH_UNUSED,
-       uintptr_t handle DISPATCH_UNUSED,
-       unsigned long mask,
-       dispatch_queue_t q DISPATCH_UNUSED)
-{
-       ds->ds_refs = calloc(1ul, sizeof(struct dispatch_timer_source_refs_s));
-       if (slowpath(!ds->ds_refs)) return;
-       ds->ds_needs_rearm = true;
-       ds->ds_is_timer = true;
-       ds_timer(ds->ds_refs).flags = mask;
-}
-
-const struct dispatch_source_type_s _dispatch_source_type_timer = {
-       .ke = {
-               .filter = DISPATCH_EVFILT_TIMER,
-       },
-       .mask = DISPATCH_TIMER_WALL_CLOCK,
-       .init = dispatch_source_type_timer_init,
-};
+#if !USE_OBJC

 
 

-const struct dispatch_source_type_s _dispatch_source_type_read = {
-       .ke = {
-               .filter = EVFILT_READ,
-               .flags = EV_DISPATCH,
-       },
-};
+static const _os_object_vtable_s _os_object_vtable;

 
 

-const struct dispatch_source_type_s _dispatch_source_type_write = {
-       .ke = {
-               .filter = EVFILT_WRITE,
-               .flags = EV_DISPATCH,
-       },
-};
+void
+_os_object_init(void)
+{
+       return;
+}

 
 

-#if DISPATCH_USE_VM_PRESSURE
-#if TARGET_IPHONE_SIMULATOR // rdar://problem/9219483
-static int _dispatch_ios_simulator_memory_warnings_fd = -1;
-static void
-_dispatch_ios_simulator_vm_source_init(void *context DISPATCH_UNUSED)
+inline _os_object_t
+_os_object_alloc_realized(const void *cls, size_t size)

 {
 {

-       char *e = getenv("IPHONE_SIMULATOR_MEMORY_WARNINGS");
-       if (!e) return;
-       _dispatch_ios_simulator_memory_warnings_fd = open(e, O_EVTONLY);
-       if (_dispatch_ios_simulator_memory_warnings_fd == -1) {
-               (void)dispatch_assume_zero(errno);
+       _os_object_t obj;
+       dispatch_assert(size >= sizeof(struct _os_object_s));
+       while (!fastpath(obj = calloc(1u, size))) {
+               _dispatch_temporary_resource_shortage();

        }
        }

+       obj->os_obj_isa = cls;
+       return obj;

 }
 }

-static void
-dispatch_source_type_vm_init(dispatch_source_t ds,
-       dispatch_source_type_t type DISPATCH_UNUSED,
-       uintptr_t handle DISPATCH_UNUSED,
-       unsigned long mask,
-       dispatch_queue_t q DISPATCH_UNUSED)
-{
-       static dispatch_once_t pred;
-       dispatch_once_f(&pred, NULL, _dispatch_ios_simulator_vm_source_init);
-       ds->ds_dkev->dk_kevent.ident = (mask & DISPATCH_VM_PRESSURE ?
-                       _dispatch_ios_simulator_memory_warnings_fd : -1);
-}
-
-const struct dispatch_source_type_s _dispatch_source_type_vm = {
-       .ke = {
-               .filter = EVFILT_VNODE,
-               .flags = EV_CLEAR,
-       },
-       .mask = NOTE_ATTRIB,
-       .init = dispatch_source_type_vm_init,
-};
-#else
-static void
-dispatch_source_type_vm_init(dispatch_source_t ds,
-       dispatch_source_type_t type DISPATCH_UNUSED,
-       uintptr_t handle DISPATCH_UNUSED,
-       unsigned long mask DISPATCH_UNUSED,
-       dispatch_queue_t q DISPATCH_UNUSED)
-{
-       ds->ds_is_level = false;
-}
-
-const struct dispatch_source_type_s _dispatch_source_type_vm = {
-       .ke = {
-               .filter = EVFILT_VM,
-               .flags = EV_DISPATCH,
-       },
-       .mask = NOTE_VM_PRESSURE,
-       .init = dispatch_source_type_vm_init,
-};
-#endif
-#endif

 
 

-const struct dispatch_source_type_s _dispatch_source_type_proc = {
-       .ke = {
-               .filter = EVFILT_PROC,
-               .flags = EV_CLEAR,
-       },
-       .mask = NOTE_EXIT|NOTE_FORK|NOTE_EXEC
-#if HAVE_DECL_NOTE_SIGNAL
-                       |NOTE_SIGNAL
-#endif
-#if HAVE_DECL_NOTE_REAP
-                       |NOTE_REAP
-#endif
-                       ,
-};
+_os_object_t
+_os_object_alloc(const void *cls, size_t size)
+{
+       if (!cls) cls = &_os_object_vtable;
+       return _os_object_alloc_realized(cls, size);
+}

 
 

-const struct dispatch_source_type_s _dispatch_source_type_signal = {
-       .ke = {
-               .filter = EVFILT_SIGNAL,
-       },
-};
+void
+_os_object_dealloc(_os_object_t obj)
+{
+       *((void *volatile*)&obj->os_obj_isa) = (void *)0x200;
+       return free(obj);
+}

 
 

-const struct dispatch_source_type_s _dispatch_source_type_vnode = {
-       .ke = {
-               .filter = EVFILT_VNODE,
-               .flags = EV_CLEAR,
-       },
-       .mask = NOTE_DELETE|NOTE_WRITE|NOTE_EXTEND|NOTE_ATTRIB|NOTE_LINK|
-                       NOTE_RENAME|NOTE_REVOKE
-#if HAVE_DECL_NOTE_NONE
-                       |NOTE_NONE
-#endif
-                       ,
-};
+void
+_os_object_xref_dispose(_os_object_t obj)
+{
+       _os_object_xrefcnt_dispose_barrier(obj);
+       if (fastpath(obj->os_obj_isa->_os_obj_xref_dispose)) {
+               return obj->os_obj_isa->_os_obj_xref_dispose(obj);
+       }
+       return _os_object_release_internal(obj);
+}

 
 

-const struct dispatch_source_type_s _dispatch_source_type_vfs = {
-       .ke = {
-               .filter = EVFILT_FS,
-               .flags = EV_CLEAR,
-       },
-       .mask = VQ_NOTRESP|VQ_NEEDAUTH|VQ_LOWDISK|VQ_MOUNT|VQ_UNMOUNT|VQ_DEAD|
-                       VQ_ASSIST|VQ_NOTRESPLOCK
-#if HAVE_DECL_VQ_UPDATE
-                       |VQ_UPDATE
-#endif
-#if HAVE_DECL_VQ_VERYLOWDISK
-                       |VQ_VERYLOWDISK
-#endif
-                       ,
-};
+void
+_os_object_dispose(_os_object_t obj)
+{
+       _os_object_refcnt_dispose_barrier(obj);
+       if (fastpath(obj->os_obj_isa->_os_obj_dispose)) {
+               return obj->os_obj_isa->_os_obj_dispose(obj);
+       }
+       return _os_object_dealloc(obj);
+}

 
 

-const struct dispatch_source_type_s _dispatch_source_type_data_add = {
-       .ke = {
-               .filter = DISPATCH_EVFILT_CUSTOM_ADD,
-       },
-};
+void*
+os_retain(void *obj)
+{
+       if (fastpath(obj)) {
+               return _os_object_retain(obj);
+       }
+       return obj;
+}

 
 

-const struct dispatch_source_type_s _dispatch_source_type_data_or = {
-       .ke = {
-               .filter = DISPATCH_EVFILT_CUSTOM_OR,
-               .flags = EV_CLEAR,
-               .fflags = ~0,
-       },
-};
+#undef os_release
+void
+os_release(void *obj)
+{
+       if (fastpath(obj)) {
+               return _os_object_release(obj);
+       }
+}

 
 

-#if HAVE_MACH
+void
+_os_object_atfork_prepare(void)
+{
+       return;
+}

 
 

-static void
-dispatch_source_type_mach_send_init(dispatch_source_t ds,
-       dispatch_source_type_t type DISPATCH_UNUSED,
-       uintptr_t handle DISPATCH_UNUSED, unsigned long mask,
-       dispatch_queue_t q DISPATCH_UNUSED)
-{
-       static dispatch_once_t pred;
-       dispatch_once_f(&pred, NULL, _dispatch_mach_notify_source_init);
-       if (!mask) {
-               // Preserve legacy behavior that (mask == 0) => DISPATCH_MACH_SEND_DEAD
-               ds->ds_dkev->dk_kevent.fflags = DISPATCH_MACH_SEND_DEAD;
-               ds->ds_pending_data_mask = DISPATCH_MACH_SEND_DEAD;
+void
+_os_object_atfork_parent(void)
+{
+       return;
+}
+
+void
+_os_object_atfork_child(void)
+{
+       return;
+}
+
+#pragma mark -
+#pragma mark dispatch_autorelease_pool no_objc
+
+#if DISPATCH_COCOA_COMPAT
+
+void*
+_dispatch_autorelease_pool_push(void)
+{
+       void *pool = NULL;
+       if (_dispatch_begin_NSAutoReleasePool) {
+               pool = _dispatch_begin_NSAutoReleasePool();

        }
        }

+       return pool;

 }
 
 }
 

-const struct dispatch_source_type_s _dispatch_source_type_mach_send = {
-       .ke = {
-               .filter = EVFILT_MACHPORT,
-               .flags = EV_CLEAR,
-       },
-       .mask = DISPATCH_MACH_SEND_DEAD|DISPATCH_MACH_SEND_POSSIBLE,
-       .init = dispatch_source_type_mach_send_init,
-};
+void
+_dispatch_autorelease_pool_pop(void *pool)
+{
+       if (_dispatch_end_NSAutoReleasePool) {
+               _dispatch_end_NSAutoReleasePool(pool);
+       }
+}

 
 

-static void
-dispatch_source_type_mach_recv_init(dispatch_source_t ds,
-       dispatch_source_type_t type DISPATCH_UNUSED,
-       uintptr_t handle DISPATCH_UNUSED,
-       unsigned long mask DISPATCH_UNUSED,
-       dispatch_queue_t q DISPATCH_UNUSED)
-{
-       ds->ds_is_level = false;
-}
-
-const struct dispatch_source_type_s _dispatch_source_type_mach_recv = {
-       .ke = {
-               .filter = EVFILT_MACHPORT,
-               .flags = EV_DISPATCH,
-               .fflags = DISPATCH_MACH_RECV_MESSAGE,
-       },
-       .init = dispatch_source_type_mach_recv_init,
-};
+void
+_dispatch_last_resort_autorelease_pool_push(dispatch_invoke_context_t dic)
+{
+       dic->dic_autorelease_pool = _dispatch_autorelease_pool_push();
+}
+
+void
+_dispatch_last_resort_autorelease_pool_pop(dispatch_invoke_context_t dic)
+{
+       _dispatch_autorelease_pool_pop(dic->dic_autorelease_pool);
+       dic->dic_autorelease_pool = NULL;
+}
+
+#endif // DISPATCH_COCOA_COMPAT
+#endif // !USE_OBJC

 
 #pragma mark -
 #pragma mark dispatch_mig
 
 #pragma mark -
 #pragma mark dispatch_mig

+#if HAVE_MACH

 
 void *
 dispatch_mach_msg_get_context(mach_msg_header_t *msg)
 
 void *
 dispatch_mach_msg_get_context(mach_msg_header_t *msg)


@@ -571,9 +1192,9 @@ dispatch_mach_msg_get_context(mach_msg_header_t *msg)
 }
 
 kern_return_t
 }
 
 kern_return_t

-_dispatch_wakeup_main_thread(mach_port_t mp DISPATCH_UNUSED)
+_dispatch_wakeup_runloop_thread(mach_port_t mp DISPATCH_UNUSED)

 {
 {

-       // dummy function just to pop out the main thread out of mach_msg()
+       // dummy function just to pop a runloop thread out of mach_msg()

        return 0;
 }
 
        return 0;
 }
 


@@ -588,22 +1209,16 @@ kern_return_t
 _dispatch_mach_notify_port_destroyed(mach_port_t notify DISPATCH_UNUSED,
                mach_port_t name)
 {
 _dispatch_mach_notify_port_destroyed(mach_port_t notify DISPATCH_UNUSED,
                mach_port_t name)
 {

-       kern_return_t kr;
-       // this function should never be called
-       (void)dispatch_assume_zero(name);
-       kr = mach_port_mod_refs(mach_task_self(), name, MACH_PORT_RIGHT_RECEIVE,-1);
-       DISPATCH_VERIFY_MIG(kr);
-       (void)dispatch_assume_zero(kr);
-       return KERN_SUCCESS;
+       DISPATCH_INTERNAL_CRASH(name, "unexpected receipt of port-destroyed");
+       return KERN_FAILURE;

 }
 
 kern_return_t
 }
 
 kern_return_t

-_dispatch_mach_notify_no_senders(mach_port_t notify,
-               mach_port_mscount_t mscnt DISPATCH_UNUSED)
+_dispatch_mach_notify_no_senders(mach_port_t notify DISPATCH_UNUSED,
+               mach_port_mscount_t mscnt)

 {
 {

-       // this function should never be called
-       (void)dispatch_assume_zero(notify);
-       return KERN_SUCCESS;
+       DISPATCH_INTERNAL_CRASH(mscnt, "unexpected receipt of no-more-senders");
+       return KERN_FAILURE;

 }
 
 kern_return_t
 }
 
 kern_return_t


@@ -618,5 +1233,4 @@ _dispatch_mach_notify_send_once(mach_port_t notify DISPATCH_UNUSED)
        return KERN_SUCCESS;
 }
 
        return KERN_SUCCESS;
 }
 

-

 #endif // HAVE_MACH
 #endif // HAVE_MACH