src/object.m

   1 /*
   2  * Copyright (c) 2011-2014 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 #include "internal.h"
  22
  23 #if USE_OBJC
  24
  25 #if _OS_OBJECT_OBJC_ARC
  26 #error "Cannot build with ARC"
  27 #endif
  28 #if defined(__OBJC_GC__)
  29 #error Objective C GC isn't supported anymore
  30 #endif
  31
  32 #include <objc/objc-internal.h>
  33 #include <objc/objc-exception.h>
  34 #include <Foundation/NSString.h>
  35
  36 #pragma mark -
  37 #pragma mark _os_object_t
  38
  39 static inline id
  40 _os_objc_alloc(Class cls, size_t size)
  41 {
  42         id obj;
  43         size -= sizeof(((struct _os_object_s *)NULL)->os_obj_isa);
  44         while (!fastpath(obj = class_createInstance(cls, size))) {
  45                 _dispatch_temporary_resource_shortage();
  46         }
  47         return obj;
  48 }
  49
  50 static void*
  51 _os_objc_destructInstance(id obj)
  52 {
  53         // noop if only Libystem is loaded
  54         return obj;
  55 }
  56
  57 #if DISPATCH_COCOA_COMPAT
  58 static bool _os_object_debug_missing_pools;
  59 #endif
  60
  61 void
  62 _os_object_init(void)
  63 {
  64         _objc_init();
  65         Block_callbacks_RR callbacks = {
  66                 sizeof(Block_callbacks_RR),
  67                 (void (*)(const void *))&objc_retain,
  68                 (void (*)(const void *))&objc_release,
  69                 (void (*)(const void *))&_os_objc_destructInstance
  70         };
  71         _Block_use_RR2(&callbacks);
  72 #if DISPATCH_COCOA_COMPAT
  73         const char *v = getenv("OBJC_DEBUG_MISSING_POOLS");
  74         _os_object_debug_missing_pools = v && !strcmp(v, "YES");
  75 #endif
  76 }
  77
  78 _os_object_t
  79 _os_object_alloc_realized(const void *cls, size_t size)
  80 {
  81         dispatch_assert(size >= sizeof(struct _os_object_s));
  82         return _os_objc_alloc(cls, size);
  83 }
  84
  85 _os_object_t
  86 _os_object_alloc(const void *_cls, size_t size)
  87 {
  88         dispatch_assert(size >= sizeof(struct _os_object_s));
  89         Class cls = _cls ? [(id)_cls class] : [OS_OBJECT_CLASS(object) class];
  90         return _os_objc_alloc(cls, size);
  91 }
  92
  93 void
  94 _os_object_dealloc(_os_object_t obj)
  95 {
  96         [obj dealloc];
  97 }
  98
  99 void
 100 _os_object_xref_dispose(_os_object_t obj)
 101 {
 102         struct _os_object_s *o = (struct _os_object_s *)obj;
 103         _os_object_xrefcnt_dispose_barrier(o);
 104         [obj _xref_dispose];
 105 }
 106
 107 void
 108 _os_object_dispose(_os_object_t obj)
 109 {
 110         struct _os_object_s *o = (struct _os_object_s *)obj;
 111         _os_object_refcnt_dispose_barrier(o);
 112         [obj _dispose];
 113 }
 114
 115 #undef os_retain
 116 void*
 117 os_retain(void *obj)
 118 {
 119         return objc_retain(obj);
 120 }
 121
 122 #undef os_release
 123 void
 124 os_release(void *obj)
 125 {
 126         return objc_release(obj);
 127 }
 128
 129 #pragma mark -
 130 #pragma mark _os_object
 131
 132 @implementation OS_OBJECT_CLASS(object)
 133 DISPATCH_UNAVAILABLE_INIT()
 134
 135 -(id)retain {
 136         return _os_object_retain(self);
 137 }
 138
 139 -(oneway void)release {
 140         return _os_object_release(self);
 141 }
 142
 143 -(NSUInteger)retainCount {
 144         return _os_object_retain_count(self);
 145 }
 146
 147 -(BOOL)retainWeakReference {
 148         return _os_object_retain_weak(self);
 149 }
 150
 151 -(BOOL)allowsWeakReference {
 152         return _os_object_allows_weak_reference(self);
 153 }
 154
 155 - (void)_xref_dispose {
 156         return _os_object_release_internal(self);
 157 }
 158
 159 - (void)_dispose {
 160         return _os_object_dealloc(self);
 161 }
 162
 163 @end
 164
 165 #pragma mark -
 166 #pragma mark _dispatch_objc
 167 #if OS_OBJECT_HAVE_OBJC2
 168
 169 id
 170 _dispatch_objc_alloc(Class cls, size_t size)
 171 {
 172         return _os_objc_alloc(cls, size);
 173 }
 174
 175 void
 176 _dispatch_objc_retain(dispatch_object_t dou)
 177 {
 178         return (void)os_retain(dou);
 179 }
 180
 181 void
 182 _dispatch_objc_release(dispatch_object_t dou)
 183 {
 184         return os_release(dou);
 185 }
 186
 187 void
 188 _dispatch_objc_set_context(dispatch_object_t dou, void *context)
 189 {
 190         return [dou _setContext:context];
 191 }
 192
 193 void *
 194 _dispatch_objc_get_context(dispatch_object_t dou)
 195 {
 196         return [dou _getContext];
 197 }
 198
 199 void
 200 _dispatch_objc_set_finalizer_f(dispatch_object_t dou,
 201                 dispatch_function_t finalizer)
 202 {
 203         return [dou _setFinalizer:finalizer];
 204 }
 205
 206 void
 207 _dispatch_objc_set_target_queue(dispatch_object_t dou, dispatch_queue_t queue)
 208 {
 209         return [dou _setTargetQueue:queue];
 210 }
 211
 212 void
 213 _dispatch_objc_suspend(dispatch_object_t dou)
 214 {
 215         return [dou _suspend];
 216 }
 217
 218 void
 219 _dispatch_objc_resume(dispatch_object_t dou)
 220 {
 221         return [dou _resume];
 222 }
 223
 224 void
 225 _dispatch_objc_activate(dispatch_object_t dou)
 226 {
 227         return [dou _activate];
 228 }
 229
 230 size_t
 231 _dispatch_objc_debug(dispatch_object_t dou, char* buf, size_t bufsiz)
 232 {
 233         NSUInteger offset = 0;
 234         NSString *desc = [dou debugDescription];
 235         [desc getBytes:buf maxLength:bufsiz-1 usedLength:&offset
 236                         encoding:NSUTF8StringEncoding options:0
 237                         range:NSMakeRange(0, [desc length]) remainingRange:NULL];
 238         if (offset) buf[offset] = 0;
 239         return offset;
 240 }
 241
 242 #endif
 243 #pragma mark -
 244 #pragma mark _dispatch_object
 245
 246 // Force non-lazy class realization rdar://10640168
 247 #define DISPATCH_OBJC_LOAD() + (void)load {}
 248
 249 @implementation DISPATCH_CLASS(object)
 250 DISPATCH_UNAVAILABLE_INIT()
 251
 252 - (void)_dispose {
 253         return _dispatch_dispose(self); // calls _os_object_dealloc()
 254 }
 255
 256 - (NSString *)debugDescription {
 257         Class nsstring = objc_lookUpClass("NSString");
 258         if (!nsstring) return nil;
 259         char buf[2048];
 260         struct dispatch_object_s *obj = (struct dispatch_object_s *)self;
 261         if (dx_vtable(obj)->do_debug) {
 262                 dx_debug(obj, buf, sizeof(buf));
 263         } else {
 264                 strlcpy(buf, dx_kind(obj), sizeof(buf));
 265         }
 266         return [nsstring stringWithFormat:
 267                         [nsstring stringWithUTF8String:"<%s: %s>"],
 268                         class_getName([self class]), buf];
 269 }
 270
 271 @end
 272
 273 @implementation DISPATCH_CLASS(queue)
 274 DISPATCH_OBJC_LOAD()
 275 DISPATCH_UNAVAILABLE_INIT()
 276
 277 - (NSString *)description {
 278         Class nsstring = objc_lookUpClass("NSString");
 279         if (!nsstring) return nil;
 280         return [nsstring stringWithFormat:
 281                         [nsstring stringWithUTF8String:"<%s: %s[%p]>"],
 282                         class_getName([self class]), dispatch_queue_get_label(self), self];
 283 }
 284
 285 - (void)_xref_dispose {
 286         _dispatch_queue_xref_dispose((struct dispatch_queue_s *)self);
 287         [super _xref_dispose];
 288 }
 289
 290 @end
 291
 292 @implementation DISPATCH_CLASS(source)
 293 DISPATCH_OBJC_LOAD()
 294 DISPATCH_UNAVAILABLE_INIT()
 295
 296 - (void)_xref_dispose {
 297         _dispatch_queue_xref_dispose((struct dispatch_queue_s *)self);
 298         _dispatch_source_xref_dispose(self);
 299         [super _xref_dispose];
 300 }
 301
 302 @end
 303
 304 @implementation DISPATCH_CLASS(mach)
 305 DISPATCH_OBJC_LOAD()
 306 DISPATCH_UNAVAILABLE_INIT()
 307
 308 - (void)_xref_dispose {
 309         _dispatch_queue_xref_dispose((struct dispatch_queue_s *)self);
 310         [super _xref_dispose];
 311 }
 312
 313 @end
 314
 315 @implementation DISPATCH_CLASS(queue_runloop)
 316 DISPATCH_OBJC_LOAD()
 317 DISPATCH_UNAVAILABLE_INIT()
 318
 319 - (void)_xref_dispose {
 320         _dispatch_queue_xref_dispose((struct dispatch_queue_s *)self);
 321         _dispatch_runloop_queue_xref_dispose(self);
 322         [super _xref_dispose];
 323 }
 324
 325 @end
 326
 327 #define DISPATCH_CLASS_IMPL(name) \
 328                 @implementation DISPATCH_CLASS(name) \
 329                 DISPATCH_OBJC_LOAD() \
 330                 DISPATCH_UNAVAILABLE_INIT() \
 331                 @end
 332
 333 #if !DISPATCH_DATA_IS_BRIDGED_TO_NSDATA
 334 DISPATCH_CLASS_IMPL(data)
 335 #endif
 336 DISPATCH_CLASS_IMPL(semaphore)
 337 DISPATCH_CLASS_IMPL(group)
 338 DISPATCH_CLASS_IMPL(queue_serial)
 339 DISPATCH_CLASS_IMPL(queue_concurrent)
 340 DISPATCH_CLASS_IMPL(queue_main)
 341 DISPATCH_CLASS_IMPL(queue_root)
 342 DISPATCH_CLASS_IMPL(queue_mgr)
 343 DISPATCH_CLASS_IMPL(queue_specific_queue)
 344 DISPATCH_CLASS_IMPL(queue_attr)
 345 DISPATCH_CLASS_IMPL(mach_msg)
 346 DISPATCH_CLASS_IMPL(io)
 347 DISPATCH_CLASS_IMPL(operation)
 348 DISPATCH_CLASS_IMPL(disk)
 349
 350 @implementation OS_OBJECT_CLASS(voucher)
 351 DISPATCH_UNAVAILABLE_INIT()
 352 DISPATCH_OBJC_LOAD()
 353
 354 - (void)_xref_dispose {
 355         return _voucher_xref_dispose(self); // calls _os_object_release_internal()
 356 }
 357
 358 - (void)_dispose {
 359         return _voucher_dispose(self); // calls _os_object_dealloc()
 360 }
 361
 362 - (NSString *)debugDescription {
 363         Class nsstring = objc_lookUpClass("NSString");
 364         if (!nsstring) return nil;
 365         char buf[2048];
 366         _voucher_debug(self, buf, sizeof(buf));
 367         return [nsstring stringWithFormat:
 368                         [nsstring stringWithUTF8String:"<%s: %s>"],
 369                         class_getName([self class]), buf];
 370 }
 371
 372 @end
 373
 374 #if VOUCHER_ENABLE_RECIPE_OBJECTS
 375 @implementation OS_OBJECT_CLASS(voucher_recipe)
 376 DISPATCH_UNAVAILABLE_INIT()
 377 DISPATCH_OBJC_LOAD()
 378
 379 - (void)_dispose {
 380
 381 }
 382
 383 - (NSString *)debugDescription {
 384         return nil; // TODO: voucher_recipe debugDescription
 385 }
 386
 387 @end
 388 #endif
 389
 390
 391 #pragma mark -
 392 #pragma mark dispatch_last_resort_autorelease_pool
 393
 394 #if DISPATCH_COCOA_COMPAT
 395
 396 void *
 397 _dispatch_last_resort_autorelease_pool_push(void)
 398 {
 399         if (!slowpath(_os_object_debug_missing_pools)) {
 400                 return _dispatch_autorelease_pool_push();
 401         }
 402         return NULL;
 403 }
 404
 405 void
 406 _dispatch_last_resort_autorelease_pool_pop(void *context)
 407 {
 408         if (!slowpath(_os_object_debug_missing_pools)) {
 409                 return _dispatch_autorelease_pool_pop(context);
 410         }
 411 }
 412
 413 #endif // DISPATCH_COCOA_COMPAT
 414
 415 #pragma mark -
 416 #pragma mark dispatch_client_callout
 417
 418 // Abort on uncaught exceptions thrown from client callouts rdar://8577499
 419 #if DISPATCH_USE_CLIENT_CALLOUT && !__USING_SJLJ_EXCEPTIONS__ && \
 420                 OS_OBJECT_HAVE_OBJC2
 421 // On platforms with zero-cost exceptions, use a compiler-generated catch-all
 422 // exception handler.
 423
 424 DISPATCH_NORETURN extern void objc_terminate(void);
 425
 426 #undef _dispatch_client_callout
 427 void
 428 _dispatch_client_callout(void *ctxt, dispatch_function_t f)
 429 {
 430         @try {
 431                 return f(ctxt);
 432         }
 433         @catch (...) {
 434                 objc_terminate();
 435         }
 436 }
 437
 438 #undef _dispatch_client_callout2
 439 void
 440 _dispatch_client_callout2(void *ctxt, size_t i, void (*f)(void *, size_t))
 441 {
 442         @try {
 443                 return f(ctxt, i);
 444         }
 445         @catch (...) {
 446                 objc_terminate();
 447         }
 448 }
 449
 450 #if HAVE_MACH
 451 #undef _dispatch_client_callout4
 452 void
 453 _dispatch_client_callout4(void *ctxt, dispatch_mach_reason_t reason,
 454                 dispatch_mach_msg_t dmsg, mach_error_t error,
 455                 dispatch_mach_handler_function_t f)
 456 {
 457         @try {
 458                 return f(ctxt, reason, dmsg, error);
 459         }
 460         @catch (...) {
 461                 objc_terminate();
 462         }
 463 }
 464 #endif // HAVE_MACH
 465
 466 #endif // DISPATCH_USE_CLIENT_CALLOUT
 467
 468 #endif // USE_OBJC