src/source_internal.h

   1 /*
   2  * Copyright (c) 2008-2013 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_APACHE_LICENSE_HEADER_START@
   5  *
   6  * Licensed under the Apache License, Version 2.0 (the "License");
   7  * you may not use this file except in compliance with the License.
   8  * You may obtain a copy of the License at
   9  *
  10  *     http://www.apache.org/licenses/LICENSE-2.0
  11  *
  12  * Unless required by applicable law or agreed to in writing, software
  13  * distributed under the License is distributed on an "AS IS" BASIS,
  14  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  15  * See the License for the specific language governing permissions and
  16  * limitations under the License.
  17  *
  18  * @APPLE_APACHE_LICENSE_HEADER_END@
  19  */
  20
  21 /*
  22  * IMPORTANT: This header file describes INTERNAL interfaces to libdispatch
  23  * which are subject to change in future releases of Mac OS X. Any applications
  24  * relying on these interfaces WILL break.
  25  */
  26
  27 #ifndef __DISPATCH_SOURCE_INTERNAL__
  28 #define __DISPATCH_SOURCE_INTERNAL__
  29
  30 #ifndef __DISPATCH_INDIRECT__
  31 #error "Please #include <dispatch/dispatch.h> instead of this file directly."
  32 #include <dispatch/base.h> // for HeaderDoc
  33 #endif
  34
  35 #define DISPATCH_EVFILT_TIMER           (-EVFILT_SYSCOUNT - 1)
  36 #define DISPATCH_EVFILT_CUSTOM_ADD      (-EVFILT_SYSCOUNT - 2)
  37 #define DISPATCH_EVFILT_CUSTOM_OR       (-EVFILT_SYSCOUNT - 3)
  38 #define DISPATCH_EVFILT_MACH_NOTIFICATION       (-EVFILT_SYSCOUNT - 4)
  39 #define DISPATCH_EVFILT_SYSCOUNT        ( EVFILT_SYSCOUNT + 4)
  40
  41 #if HAVE_MACH
  42 // NOTE: dispatch_source_mach_send_flags_t and dispatch_source_mach_recv_flags_t
  43 //       bit values must not overlap as they share the same kevent fflags !
  44
  45 /*!
  46  * @enum dispatch_source_mach_send_flags_t
  47  *
  48  * @constant DISPATCH_MACH_SEND_DELETED
  49  * Port-deleted notification. Disabled for source registration.
  50  */
  51 enum {
  52         DISPATCH_MACH_SEND_DELETED = 0x4,
  53 };
  54 /*!
  55  * @enum dispatch_source_mach_recv_flags_t
  56  *
  57  * @constant DISPATCH_MACH_RECV_MESSAGE
  58  * Receive right has pending messages
  59  *
  60  * @constant DISPATCH_MACH_RECV_MESSAGE_DIRECT
  61  * Receive messages from receive right directly via kevent64()
  62  *
  63  * @constant DISPATCH_MACH_RECV_NO_SENDERS
  64  * Receive right has no more senders. TODO <rdar://problem/8132399>
  65  */
  66 enum {
  67         DISPATCH_MACH_RECV_MESSAGE = 0x2,
  68         DISPATCH_MACH_RECV_MESSAGE_DIRECT = 0x10,
  69         DISPATCH_MACH_RECV_MESSAGE_DIRECT_ONCE = 0x20,
  70         DISPATCH_MACH_RECV_NO_SENDERS = 0x40,
  71 };
  72 #endif // HAVE_MACH
  73
  74 enum {
  75         /* DISPATCH_TIMER_STRICT 0x1 */
  76         /* DISPATCH_TIMER_BACKGROUND = 0x2, */
  77         DISPATCH_TIMER_WALL_CLOCK = 0x4,
  78         DISPATCH_TIMER_INTERVAL = 0x8,
  79         DISPATCH_TIMER_WITH_AGGREGATE = 0x10,
  80         /* DISPATCH_INTERVAL_UI_ANIMATION = 0x20 */
  81         DISPATCH_TIMER_AFTER = 0x40,
  82 };
  83
  84 #define DISPATCH_TIMER_QOS_NORMAL 0u
  85 #define DISPATCH_TIMER_QOS_CRITICAL 1u
  86 #define DISPATCH_TIMER_QOS_BACKGROUND 2u
  87 #define DISPATCH_TIMER_QOS_COUNT (DISPATCH_TIMER_QOS_BACKGROUND + 1)
  88 #define DISPATCH_TIMER_QOS(tidx) (((uintptr_t)(tidx) >> 1) & 0x3ul)
  89
  90 #define DISPATCH_TIMER_CLOCK(tidx) ((dispatch_clock_t)((uintptr_t)(tidx) & 1))
  91
  92 #define DISPATCH_TIMER_INDEX(clock, qos) ((qos) << 1 | (clock))
  93 #define DISPATCH_TIMER_INDEX_DISARM \
  94                 DISPATCH_TIMER_INDEX(0, DISPATCH_TIMER_QOS_COUNT)
  95 #define DISPATCH_TIMER_INDEX_COUNT (DISPATCH_TIMER_INDEX_DISARM + 1)
  96 #define DISPATCH_TIMER_IDENT(flags) ({ unsigned long f = (flags); \
  97                 DISPATCH_TIMER_INDEX(f & DISPATCH_TIMER_WALL_CLOCK ? \
  98                 DISPATCH_CLOCK_WALL : DISPATCH_CLOCK_MACH, \
  99                 f & DISPATCH_TIMER_STRICT ? DISPATCH_TIMER_QOS_CRITICAL : \
 100                 f & DISPATCH_TIMER_BACKGROUND ? DISPATCH_TIMER_QOS_BACKGROUND : \
 101                 DISPATCH_TIMER_QOS_NORMAL); })
 102
 103 struct dispatch_kevent_s {
 104         TAILQ_ENTRY(dispatch_kevent_s) dk_list;
 105         TAILQ_HEAD(, dispatch_source_refs_s) dk_sources;
 106         _dispatch_kevent_qos_s dk_kevent;
 107 };
 108
 109 typedef struct dispatch_kevent_s *dispatch_kevent_t;
 110
 111 typedef typeof(((dispatch_kevent_t)NULL)->dk_kevent.udata) _dispatch_kevent_qos_udata_t;
 112
 113 #define DISPATCH_KEV_CUSTOM_ADD ((dispatch_kevent_t)DISPATCH_EVFILT_CUSTOM_ADD)
 114 #define DISPATCH_KEV_CUSTOM_OR  ((dispatch_kevent_t)DISPATCH_EVFILT_CUSTOM_OR)
 115
 116 struct dispatch_source_type_s {
 117         _dispatch_kevent_qos_s ke;
 118         uint64_t mask;
 119         void (*init)(dispatch_source_t ds, dispatch_source_type_t type,
 120                         uintptr_t handle, unsigned long mask);
 121 };
 122
 123 struct dispatch_timer_source_s {
 124         uint64_t target;
 125         uint64_t deadline;
 126         uint64_t last_fire;
 127         uint64_t interval;
 128         uint64_t leeway;
 129         unsigned long flags; // dispatch_timer_flags_t
 130         unsigned long missed;
 131 };
 132
 133 enum {
 134         DS_EVENT_HANDLER = 0,
 135         DS_CANCEL_HANDLER,
 136         DS_REGISTN_HANDLER,
 137 };
 138
 139 // Source state which may contain references to the source object
 140 // Separately allocated so that 'leaks' can see sources <rdar://problem/9050566>
 141 typedef struct dispatch_source_refs_s {
 142         TAILQ_ENTRY(dispatch_source_refs_s) dr_list;
 143         uintptr_t dr_source_wref; // "weak" backref to dispatch_source_t
 144         dispatch_continuation_t volatile ds_handler[3];
 145 } *dispatch_source_refs_t;
 146
 147 typedef struct dispatch_timer_source_refs_s {
 148         struct dispatch_source_refs_s _ds_refs;
 149         struct dispatch_timer_source_s _ds_timer;
 150         TAILQ_ENTRY(dispatch_timer_source_refs_s) dt_list;
 151 } *dispatch_timer_source_refs_t;
 152
 153 typedef struct dispatch_timer_source_aggregate_refs_s {
 154         struct dispatch_timer_source_refs_s _dsa_refs;
 155         TAILQ_ENTRY(dispatch_timer_source_aggregate_refs_s) dra_list;
 156         TAILQ_ENTRY(dispatch_timer_source_aggregate_refs_s) dta_list;
 157 } *dispatch_timer_source_aggregate_refs_t;
 158
 159 #define _dispatch_ptr2wref(ptr) (~(uintptr_t)(ptr))
 160 #define _dispatch_wref2ptr(ref) ((void*)~(ref))
 161 #define _dispatch_source_from_refs(dr) \
 162                 ((dispatch_source_t)_dispatch_wref2ptr((dr)->dr_source_wref))
 163 #define ds_timer(dr) \
 164                 (((dispatch_timer_source_refs_t)(dr))->_ds_timer)
 165 #define ds_timer_aggregate(ds) \
 166                 ((dispatch_timer_aggregate_t)((ds)->dq_specific_q))
 167
 168 DISPATCH_ALWAYS_INLINE
 169 static inline unsigned int
 170 _dispatch_source_timer_idx(dispatch_source_refs_t dr)
 171 {
 172         return DISPATCH_TIMER_IDENT(ds_timer(dr).flags);
 173 }
 174
 175 #define _DISPATCH_SOURCE_HEADER(refs) \
 176         DISPATCH_QUEUE_HEADER(refs); \
 177         /* LP64: fills 32bit hole in QUEUE_HEADER */ \
 178         unsigned int \
 179                 ds_is_level:1, \
 180                 ds_is_adder:1, \
 181                 ds_is_installed:1, \
 182                 ds_is_direct_kevent:1, \
 183                 ds_is_custom_source:1, \
 184                 ds_needs_rearm:1, \
 185                 ds_is_timer:1, \
 186                 ds_vmpressure_override:1, \
 187                 ds_memorypressure_override:1, \
 188                 dm_handler_is_block:1, \
 189                 dm_connect_handler_called:1, \
 190                 dm_cancel_handler_called:1; \
 191         dispatch_kevent_t ds_dkev; \
 192         dispatch_##refs##_refs_t ds_refs; \
 193         unsigned long ds_pending_data_mask;
 194
 195 #define DISPATCH_SOURCE_HEADER(refs) \
 196         struct dispatch_source_s _as_ds[0]; \
 197         _DISPATCH_SOURCE_HEADER(refs)
 198
 199 DISPATCH_CLASS_DECL_BARE(source);
 200 _OS_OBJECT_CLASS_IMPLEMENTS_PROTOCOL(dispatch_source, dispatch_object);
 201
 202 #if DISPATCH_PURE_C
 203 struct dispatch_source_s {
 204         _DISPATCH_SOURCE_HEADER(source);
 205         unsigned long ds_ident_hack;
 206         unsigned long ds_data;
 207         unsigned long ds_pending_data;
 208 } DISPATCH_QUEUE_ALIGN;
 209 #endif
 210
 211 #if HAVE_MACH
 212 // Mach channel state which may contain references to the channel object
 213 // layout must match dispatch_source_refs_s
 214 struct dispatch_mach_refs_s {
 215         TAILQ_ENTRY(dispatch_mach_refs_s) dr_list;
 216         uintptr_t dr_source_wref; // "weak" backref to dispatch_mach_t
 217         dispatch_mach_handler_function_t dm_handler_func;
 218         void *dm_handler_ctxt;
 219 };
 220 typedef struct dispatch_mach_refs_s *dispatch_mach_refs_t;
 221
 222 struct dispatch_mach_reply_refs_s {
 223         TAILQ_ENTRY(dispatch_mach_reply_refs_s) dr_list;
 224         uintptr_t dr_source_wref; // "weak" backref to dispatch_mach_t
 225         dispatch_kevent_t dmr_dkev;
 226         void *dmr_ctxt;
 227         mach_port_t dmr_reply;
 228         dispatch_priority_t dmr_priority;
 229         voucher_t dmr_voucher;
 230         TAILQ_ENTRY(dispatch_mach_reply_refs_s) dmr_list;
 231 };
 232 typedef struct dispatch_mach_reply_refs_s *dispatch_mach_reply_refs_t;
 233
 234 #define _DISPATCH_MACH_STATE_UNUSED_MASK_2       0xff00000000000000ull
 235 #define DISPATCH_MACH_STATE_OVERRIDE_MASK        0x00ffff0000000000ull
 236 #define _DISPATCH_MACH_STATE_UNUSED_MASK_1       0x000000f000000000ull
 237 #define DISPATCH_MACH_STATE_DIRTY                0x0000000800000000ull
 238 #define DISPATCH_MACH_STATE_RECEIVED_OVERRIDE    0x0000000400000000ull
 239 #define _DISPATCH_MACH_STATE_UNUSED_MASK_0       0x0000000200000000ull
 240 #define DISPATCH_MACH_STATE_PENDING_BARRIER      0x0000000100000000ull
 241 #define DISPATCH_MACH_STATE_UNLOCK_MASK          0x00000000ffffffffull
 242
 243 struct dispatch_mach_send_refs_s {
 244         TAILQ_ENTRY(dispatch_mach_send_refs_s) dr_list;
 245         uintptr_t dr_source_wref; // "weak" backref to dispatch_mach_t
 246         dispatch_mach_msg_t dm_checkin;
 247         TAILQ_HEAD(, dispatch_mach_reply_refs_s) dm_replies;
 248         dispatch_unfair_lock_s dm_replies_lock;
 249 #define DISPATCH_MACH_DISCONNECT_MAGIC_BASE (0x80000000)
 250 #define DISPATCH_MACH_NEVER_INSTALLED (DISPATCH_MACH_DISCONNECT_MAGIC_BASE + 0)
 251 #define DISPATCH_MACH_NEVER_CONNECTED (DISPATCH_MACH_DISCONNECT_MAGIC_BASE + 1)
 252         uint32_t volatile dm_disconnect_cnt;
 253         union {
 254                 uint64_t volatile dm_state;
 255                 DISPATCH_STRUCT_LITTLE_ENDIAN_2(
 256                         dispatch_unfair_lock_s dm_state_lock,
 257                         uint32_t dm_state_bits
 258                 );
 259         };
 260         unsigned int dm_needs_mgr:1;
 261         struct dispatch_object_s *volatile dm_tail;
 262         struct dispatch_object_s *volatile dm_head;
 263         mach_port_t dm_send, dm_checkin_port;
 264 };
 265 typedef struct dispatch_mach_send_refs_s *dispatch_mach_send_refs_t;
 266
 267 DISPATCH_CLASS_DECL(mach);
 268 #if DISPATCH_PURE_C
 269 struct dispatch_mach_s {
 270         DISPATCH_SOURCE_HEADER(mach);
 271         dispatch_kevent_t dm_dkev;
 272         dispatch_mach_send_refs_t dm_refs;
 273 } DISPATCH_QUEUE_ALIGN;
 274 #endif
 275
 276 DISPATCH_CLASS_DECL(mach_msg);
 277 struct dispatch_mach_msg_s {
 278         DISPATCH_OBJECT_HEADER(mach_msg);
 279         union {
 280                 mach_msg_option_t dmsg_options;
 281                 mach_error_t dmsg_error;
 282         };
 283         mach_port_t dmsg_reply;
 284         pthread_priority_t dmsg_priority;
 285         voucher_t dmsg_voucher;
 286         dispatch_mach_msg_destructor_t dmsg_destructor;
 287         size_t dmsg_size;
 288         union {
 289                 mach_msg_header_t *dmsg_msg;
 290                 char dmsg_buf[0];
 291         };
 292 };
 293 #endif // HAVE_MACH
 294
 295 extern const struct dispatch_source_type_s _dispatch_source_type_after;
 296
 297 #if TARGET_OS_EMBEDDED
 298 #define DSL_HASH_SIZE  64u // must be a power of two
 299 #else
 300 #define DSL_HASH_SIZE 256u // must be a power of two
 301 #endif
 302
 303 dispatch_source_t
 304 _dispatch_source_create_mach_msg_direct_recv(mach_port_t recvp,
 305                 const struct dispatch_continuation_s *dc);
 306 void _dispatch_source_xref_dispose(dispatch_source_t ds);
 307 void _dispatch_source_dispose(dispatch_source_t ds);
 308 void _dispatch_source_finalize_activation(dispatch_source_t ds);
 309 void _dispatch_source_invoke(dispatch_source_t ds, dispatch_invoke_flags_t flags);
 310 void _dispatch_source_wakeup(dispatch_source_t ds, pthread_priority_t pp,
 311                 dispatch_wakeup_flags_t flags);
 312 size_t _dispatch_source_debug(dispatch_source_t ds, char* buf, size_t bufsiz);
 313 void _dispatch_source_set_interval(dispatch_source_t ds, uint64_t interval);
 314 void _dispatch_source_set_event_handler_continuation(dispatch_source_t ds,
 315                 dispatch_continuation_t dc);
 316 DISPATCH_EXPORT // for firehose server
 317 void _dispatch_source_merge_data(dispatch_source_t ds, pthread_priority_t pp,
 318                 unsigned long val);
 319
 320 #if HAVE_MACH
 321 void _dispatch_mach_dispose(dispatch_mach_t dm);
 322 void _dispatch_mach_finalize_activation(dispatch_mach_t dm);
 323 void _dispatch_mach_invoke(dispatch_mach_t dm, dispatch_invoke_flags_t flags);
 324 void _dispatch_mach_wakeup(dispatch_mach_t dm, pthread_priority_t pp,
 325                 dispatch_wakeup_flags_t flags);
 326 size_t _dispatch_mach_debug(dispatch_mach_t dm, char* buf, size_t bufsiz);
 327
 328 void _dispatch_mach_msg_dispose(dispatch_mach_msg_t dmsg);
 329 void _dispatch_mach_msg_invoke(dispatch_mach_msg_t dmsg,
 330                 dispatch_invoke_flags_t flags);
 331 size_t _dispatch_mach_msg_debug(dispatch_mach_msg_t dmsg, char* buf,
 332                 size_t bufsiz);
 333
 334 void _dispatch_mach_send_barrier_drain_invoke(dispatch_continuation_t dc,
 335                 dispatch_invoke_flags_t flags);
 336 void _dispatch_mach_barrier_invoke(dispatch_continuation_t dc,
 337                 dispatch_invoke_flags_t flags);
 338 #endif // HAVE_MACH
 339
 340 void _dispatch_mgr_queue_wakeup(dispatch_queue_t dq, pthread_priority_t pp,
 341                 dispatch_wakeup_flags_t flags);
 342 void _dispatch_mgr_thread(dispatch_queue_t dq, dispatch_invoke_flags_t flags);
 343 #if DISPATCH_USE_KEVENT_WORKQUEUE
 344 void _dispatch_kevent_worker_thread(_dispatch_kevent_qos_s **events,
 345                 int *nevents);
 346 #endif
 347
 348 #endif /* __DISPATCH_SOURCE_INTERNAL__ */