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 // NOTE: dispatch_source_mach_send_flags_t and dispatch_source_mach_recv_flags_t
  42 //       bit values must not overlap as they share the same kevent fflags !
  43
  44 /*!
  45  * @enum dispatch_source_mach_send_flags_t
  46  *
  47  * @constant DISPATCH_MACH_SEND_DELETED
  48  * Port-deleted notification. Disabled for source registration.
  49  */
  50 enum {
  51         DISPATCH_MACH_SEND_DELETED = 0x4,
  52 };
  53 /*!
  54  * @enum dispatch_source_mach_recv_flags_t
  55  *
  56  * @constant DISPATCH_MACH_RECV_MESSAGE
  57  * Receive right has pending messages
  58  *
  59  * @constant DISPATCH_MACH_RECV_MESSAGE_DIRECT
  60  * Receive messages from receive right directly via kevent64()
  61  *
  62  * @constant DISPATCH_MACH_RECV_NO_SENDERS
  63  * Receive right has no more senders. TODO <rdar://problem/8132399>
  64  */
  65 enum {
  66         DISPATCH_MACH_RECV_MESSAGE = 0x2,
  67         DISPATCH_MACH_RECV_MESSAGE_DIRECT = 0x10,
  68         DISPATCH_MACH_RECV_MESSAGE_DIRECT_ONCE = 0x20,
  69         DISPATCH_MACH_RECV_NO_SENDERS = 0x40,
  70 };
  71
  72 enum {
  73         DISPATCH_TIMER_WALL_CLOCK = 0x4,
  74         DISPATCH_TIMER_INTERVAL = 0x8,
  75         DISPATCH_TIMER_WITH_AGGREGATE = 0x10,
  76 };
  77
  78 // low bits are timer QoS class
  79 #define DISPATCH_TIMER_QOS_NORMAL 0u
  80 #define DISPATCH_TIMER_QOS_CRITICAL 1u
  81 #define DISPATCH_TIMER_QOS_BACKGROUND 2u
  82 #define DISPATCH_TIMER_QOS_COUNT (DISPATCH_TIMER_QOS_BACKGROUND + 1)
  83 #define DISPATCH_TIMER_QOS(tidx) ((uintptr_t)(tidx) & 0x3ul)
  84
  85 #define DISPATCH_TIMER_KIND_WALL 0u
  86 #define DISPATCH_TIMER_KIND_MACH 1u
  87 #define DISPATCH_TIMER_KIND_COUNT (DISPATCH_TIMER_KIND_MACH + 1)
  88 #define DISPATCH_TIMER_KIND(tidx) (((uintptr_t)(tidx) >> 2) & 0x1ul)
  89
  90 #define DISPATCH_TIMER_INDEX(kind, qos) (((kind) << 2) | (qos))
  91 #define DISPATCH_TIMER_INDEX_DISARM \
  92                 DISPATCH_TIMER_INDEX(DISPATCH_TIMER_KIND_COUNT, 0)
  93 #define DISPATCH_TIMER_INDEX_COUNT (DISPATCH_TIMER_INDEX_DISARM + 1)
  94 #define DISPATCH_TIMER_IDENT(flags) ({ unsigned long f = (flags); \
  95                 DISPATCH_TIMER_INDEX(f & DISPATCH_TIMER_WALL_CLOCK ? \
  96                 DISPATCH_TIMER_KIND_WALL : DISPATCH_TIMER_KIND_MACH, \
  97                 f & DISPATCH_TIMER_STRICT ? DISPATCH_TIMER_QOS_CRITICAL : \
  98                 f & DISPATCH_TIMER_BACKGROUND ? DISPATCH_TIMER_QOS_BACKGROUND : \
  99                 DISPATCH_TIMER_QOS_NORMAL); })
 100
 101 struct dispatch_kevent_s {
 102         TAILQ_ENTRY(dispatch_kevent_s) dk_list;
 103         TAILQ_HEAD(, dispatch_source_refs_s) dk_sources;
 104         struct kevent64_s dk_kevent;
 105 };
 106
 107 typedef struct dispatch_kevent_s *dispatch_kevent_t;
 108
 109 struct dispatch_source_type_s {
 110         struct kevent64_s ke;
 111         uint64_t mask;
 112         void (*init)(dispatch_source_t ds, dispatch_source_type_t type,
 113                         uintptr_t handle, unsigned long mask, dispatch_queue_t q);
 114 };
 115
 116 struct dispatch_timer_source_s {
 117         uint64_t target;
 118         uint64_t deadline;
 119         uint64_t last_fire;
 120         uint64_t interval;
 121         uint64_t leeway;
 122         unsigned long flags; // dispatch_timer_flags_t
 123         unsigned long missed;
 124 };
 125
 126 // Source state which may contain references to the source object
 127 // Separately allocated so that 'leaks' can see sources <rdar://problem/9050566>
 128 typedef struct dispatch_source_refs_s {
 129         TAILQ_ENTRY(dispatch_source_refs_s) dr_list;
 130         uintptr_t dr_source_wref; // "weak" backref to dispatch_source_t
 131         dispatch_function_t ds_handler_func;
 132         void *ds_handler_ctxt;
 133         void *ds_cancel_handler;
 134         void *ds_registration_handler;
 135 } *dispatch_source_refs_t;
 136
 137 typedef struct dispatch_timer_source_refs_s {
 138         struct dispatch_source_refs_s _ds_refs;
 139         struct dispatch_timer_source_s _ds_timer;
 140         TAILQ_ENTRY(dispatch_timer_source_refs_s) dt_list;
 141 } *dispatch_timer_source_refs_t;
 142
 143 typedef struct dispatch_timer_source_aggregate_refs_s {
 144         struct dispatch_timer_source_refs_s _dsa_refs;
 145         TAILQ_ENTRY(dispatch_timer_source_aggregate_refs_s) dra_list;
 146         TAILQ_ENTRY(dispatch_timer_source_aggregate_refs_s) dta_list;
 147 } *dispatch_timer_source_aggregate_refs_t;
 148
 149 #define _dispatch_ptr2wref(ptr) (~(uintptr_t)(ptr))
 150 #define _dispatch_wref2ptr(ref) ((void*)~(ref))
 151 #define _dispatch_source_from_refs(dr) \
 152                 ((dispatch_source_t)_dispatch_wref2ptr((dr)->dr_source_wref))
 153 #define ds_timer(dr) \
 154                 (((dispatch_timer_source_refs_t)(dr))->_ds_timer)
 155 #define ds_timer_aggregate(ds) \
 156                 ((dispatch_timer_aggregate_t)((ds)->dq_specific_q))
 157
 158 DISPATCH_ALWAYS_INLINE
 159 static inline unsigned int
 160 _dispatch_source_timer_idx(dispatch_source_refs_t dr)
 161 {
 162         return DISPATCH_TIMER_IDENT(ds_timer(dr).flags);
 163 }
 164
 165 // ds_atomic_flags bits
 166 #define DSF_CANCELED 1u // cancellation has been requested
 167 #define DSF_ARMED 2u // source is armed
 168
 169 #define DISPATCH_SOURCE_HEADER(refs) \
 170         dispatch_kevent_t ds_dkev; \
 171         dispatch_##refs##_refs_t ds_refs; \
 172         unsigned int ds_atomic_flags; \
 173         unsigned int \
 174                 ds_is_level:1, \
 175                 ds_is_adder:1, \
 176                 ds_is_installed:1, \
 177                 ds_needs_rearm:1, \
 178                 ds_is_timer:1, \
 179                 ds_cancel_is_block:1, \
 180                 ds_handler_is_block:1, \
 181                 ds_registration_is_block:1, \
 182                 dm_connect_handler_called:1, \
 183                 dm_cancel_handler_called:1; \
 184         unsigned long ds_pending_data_mask;
 185
 186 DISPATCH_CLASS_DECL(source);
 187 struct dispatch_source_s {
 188         DISPATCH_STRUCT_HEADER(source);
 189         DISPATCH_QUEUE_HEADER;
 190         DISPATCH_SOURCE_HEADER(source);
 191         unsigned long ds_ident_hack;
 192         unsigned long ds_data;
 193         unsigned long ds_pending_data;
 194 };
 195
 196 // Mach channel state which may contain references to the channel object
 197 // layout must match dispatch_source_refs_s
 198 struct dispatch_mach_refs_s {
 199         TAILQ_ENTRY(dispatch_mach_refs_s) dr_list;
 200         uintptr_t dr_source_wref; // "weak" backref to dispatch_mach_t
 201         dispatch_mach_handler_function_t dm_handler_func;
 202         void *dm_handler_ctxt;
 203 };
 204 typedef struct dispatch_mach_refs_s *dispatch_mach_refs_t;
 205
 206 struct dispatch_mach_reply_refs_s {
 207         TAILQ_ENTRY(dispatch_mach_reply_refs_s) dr_list;
 208         uintptr_t dr_source_wref; // "weak" backref to dispatch_mach_t
 209         dispatch_kevent_t dm_dkev;
 210         TAILQ_ENTRY(dispatch_mach_reply_refs_s) dm_list;
 211 };
 212 typedef struct dispatch_mach_reply_refs_s *dispatch_mach_reply_refs_t;
 213
 214 struct dispatch_mach_send_refs_s {
 215         TAILQ_ENTRY(dispatch_mach_send_refs_s) dr_list;
 216         uintptr_t dr_source_wref; // "weak" backref to dispatch_mach_t
 217         dispatch_mach_msg_t dm_checkin;
 218         TAILQ_HEAD(, dispatch_mach_reply_refs_s) dm_replies;
 219         uint32_t volatile dm_disconnect_cnt;
 220         uint32_t volatile dm_sending;
 221         unsigned int dm_needs_mgr:1;
 222         struct dispatch_object_s *volatile dm_tail;
 223         struct dispatch_object_s *volatile dm_head;
 224         mach_port_t dm_send, dm_checkin_port;
 225 };
 226 typedef struct dispatch_mach_send_refs_s *dispatch_mach_send_refs_t;
 227
 228 DISPATCH_CLASS_DECL(mach);
 229 struct dispatch_mach_s {
 230         DISPATCH_STRUCT_HEADER(mach);
 231         DISPATCH_QUEUE_HEADER;
 232         DISPATCH_SOURCE_HEADER(mach);
 233         dispatch_kevent_t dm_dkev;
 234         dispatch_mach_send_refs_t dm_refs;
 235 };
 236
 237 DISPATCH_CLASS_DECL(mach_msg);
 238 struct dispatch_mach_msg_s {
 239         DISPATCH_STRUCT_HEADER(mach_msg);
 240         dispatch_mach_msg_destructor_t destructor;
 241         size_t size;
 242         union {
 243                 mach_msg_header_t *msg;
 244                 char buf[0];
 245         };
 246 };
 247
 248 #if TARGET_OS_EMBEDDED
 249 #define DSL_HASH_SIZE  64u // must be a power of two
 250 #else
 251 #define DSL_HASH_SIZE 256u // must be a power of two
 252 #endif
 253
 254 void _dispatch_source_xref_dispose(dispatch_source_t ds);
 255 void _dispatch_source_dispose(dispatch_source_t ds);
 256 void _dispatch_source_invoke(dispatch_source_t ds);
 257 unsigned long _dispatch_source_probe(dispatch_source_t ds);
 258 size_t _dispatch_source_debug(dispatch_source_t ds, char* buf, size_t bufsiz);
 259 void _dispatch_source_set_interval(dispatch_source_t ds, uint64_t interval);
 260
 261 void _dispatch_mach_dispose(dispatch_mach_t dm);
 262 void _dispatch_mach_invoke(dispatch_mach_t dm);
 263 unsigned long _dispatch_mach_probe(dispatch_mach_t dm);
 264 size_t _dispatch_mach_debug(dispatch_mach_t dm, char* buf, size_t bufsiz);
 265
 266 void _dispatch_mach_msg_dispose(dispatch_mach_msg_t dmsg);
 267 void _dispatch_mach_msg_invoke(dispatch_mach_msg_t dmsg);
 268 size_t _dispatch_mach_msg_debug(dispatch_mach_msg_t dmsg, char* buf, size_t bufsiz);
 269
 270 void _dispatch_mach_barrier_invoke(void *ctxt);
 271
 272 unsigned long _dispatch_mgr_wakeup(dispatch_queue_t dq);
 273 void _dispatch_mgr_thread(dispatch_queue_t dq);
 274
 275 #endif /* __DISPATCH_SOURCE_INTERNAL__ */