CFUUID.c

   1 /*
   2  * Copyright (c) 2015 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23
  24 /*      CFUUID.c
  25         Copyright (c) 1999-2014, Apple Inc.  All rights reserved.
  26         Responsibility: David Smith
  27 */
  28
  29 #include <CoreFoundation/CFUUID.h>
  30 #include "CFInternal.h"
  31
  32 #if DEPLOYMENT_TARGET_MACOSX || DEPLOYMENT_TARGET_EMBEDDED || DEPLOYMENT_TARGET_WINDOWS
  33 #include <dispatch/dispatch.h>
  34
  35 static CFMutableDictionaryRef _uniquedUUIDs = NULL;
  36 CF_INLINE void LOCKED(dispatch_block_t work) {
  37     static dispatch_once_t guard;
  38     static dispatch_queue_t CFUUIDGlobalDataLock;
  39     dispatch_once(&guard, ^{
  40         dispatch_queue_attr_t dqattr = dispatch_queue_attr_make_with_qos_class(DISPATCH_QUEUE_SERIAL, qos_class_main(), 0);
  41         CFUUIDGlobalDataLock = dispatch_queue_create("com.apple.CFUUID", dqattr);
  42     });
  43     dispatch_sync(CFUUIDGlobalDataLock, work);
  44 }
  45
  46 #else
  47 // Platforms without dispatch
  48
  49 static CFMutableDictionaryRef _uniquedUUIDs = NULL;
  50 static CFLock_t _uniquedUUIDsLock = CFLockInit;
  51
  52 CF_INLINE void LOCKED(void (^work)(void)) {
  53     __CFLock(&_uniquedUUIDsLock);
  54     work();
  55     __CFUnlock(&_uniquedUUIDsLock);
  56 }
  57
  58 #endif
  59
  60 struct __CFUUID {
  61     CFRuntimeBase _base;
  62     CFUUIDBytes _bytes;
  63 };
  64
  65 typedef struct __CFUUID __CFUUID_t;
  66
  67 static Boolean __CFisEqualUUIDBytes(const void *ptr1, const void *ptr2) {
  68     CFUUIDBytes *p1 = (CFUUIDBytes *)ptr1;
  69     CFUUIDBytes *p2 = (CFUUIDBytes *)ptr2;
  70
  71     return (((p1->byte0 == p2->byte0) && (p1->byte1 == p2->byte1) && (p1->byte2 == p2->byte2) && (p1->byte3 == p2->byte3) && (p1->byte4 == p2->byte4) && (p1->byte5 == p2->byte5) && (p1->byte6 == p2->byte6) && (p1->byte7 == p2->byte7) && (p1->byte8 == p2->byte8) && (p1->byte9 == p2->byte9) && (p1->byte10 == p2->byte10) && (p1->byte11 == p2->byte11) && (p1->byte12 == p2->byte12) && (p1->byte13 == p2->byte13) && (p1->byte14 == p2->byte14) && (p1->byte15 == p2->byte15)) ? true : false);
  72 }
  73
  74 static CFHashCode __CFhashUUIDBytes(const void *ptr) {
  75     return CFHashBytes((uint8_t *)ptr, 16);
  76 }
  77
  78 /*
  79  * GC implementation of a weak set specifically designed for UUID
  80  */
  81
  82 #define MALLOC(x) CFAllocatorAllocate(kCFAllocatorSystemDefault, x, 0)
  83 #define FREE(x) CFAllocatorDeallocate(kCFAllocatorSystemDefault, x)
  84 #define HASH(x) CFHashBytes((uint8_t *)x, 16)
  85
  86 #define READWEAK(location) objc_read_weak((id *)location)
  87 #define WRITEWEAK(location, value) objc_assign_weak((id)value, (id *)location)
  88
  89 typedef struct {
  90     unsigned long count, size;
  91     __CFUUID_t **weakPtrs;
  92 } _UUIDWeakSet_t;
  93
  94 static _UUIDWeakSet_t _UUIDWeakSet;
  95
  96 static void grow_has_lock(void);
  97
  98 // enter if not already present
  99 static void enter_has_lock(__CFUUID_t *candidate) {
 100     if (!candidate) return;
 101     _UUIDWeakSet_t *table = &_UUIDWeakSet;
 102     if (!table->size) grow_has_lock();
 103     unsigned long int hashValue = HASH(&candidate->_bytes) & (table->size-1);
 104     __CFUUID_t *result = table->weakPtrs[hashValue];
 105     while (1) {
 106         if (result == (void *)0x1 || result == NULL) {
 107             table->weakPtrs[hashValue] = NULL;  // so that we don't try to unregister 0x1
 108             WRITEWEAK(&table->weakPtrs[hashValue], (void *)candidate);
 109             ++table->count;
 110             break;
 111         }
 112         if (result) result = (__CFUUID_t *)READWEAK(&table->weakPtrs[hashValue]);
 113         if (result) {
 114             // see if it is equal to candidate
 115             if (__CFisEqualUUIDBytes(&result->_bytes, &candidate->_bytes)) {
 116                 // keep first one.  There is a race if two threads both fail to find
 117                 // a candidate uuid then both try decide to create and enter one.
 118                 // Under non-GC one of them simply leaks.
 119                 break;
 120             }
 121         } else {
 122             // was zeroed by collector.  Use this slot.
 123             continue;
 124         }
 125         // move on
 126         if (++hashValue >= table->size) hashValue = 0;
 127         result = table->weakPtrs[hashValue];
 128     }
 129 }
 130
 131 static void *find_has_lock(const CFUUIDBytes *bytes) {
 132     if (!bytes) return NULL;
 133     _UUIDWeakSet_t *table = &_UUIDWeakSet;
 134     if (!table->size) return NULL;  // no entries
 135     unsigned long int hashValue = HASH(bytes) & (table->size-1);
 136     __CFUUID_t *result = table->weakPtrs[hashValue];
 137     while (1) {
 138         if (result == (void *)0x1) break;
 139         if (result) result = (__CFUUID_t *)READWEAK(&table->weakPtrs[hashValue]);
 140         if (result) {
 141             // see if it is equal to bytes
 142             if (__CFisEqualUUIDBytes(&result->_bytes, bytes)) return result;
 143         }
 144         // move on
 145         if (++hashValue >= table->size) hashValue = 0;
 146         result = table->weakPtrs[hashValue];
 147     }
 148     return NULL;
 149 }
 150
 151
 152 static void grow_has_lock() {
 153     _UUIDWeakSet_t *table = &_UUIDWeakSet;
 154     if (table->size == 0) {
 155         table->size = 16;
 156         table->weakPtrs = (__CFUUID_t **)MALLOC(sizeof(__CFUUID_t *)*table->size);
 157         for (int i = 0; i < table->size; ++i) table->weakPtrs[i] = (__CFUUID_t *)0x1;
 158         table->count = 0;
 159         return;
 160     }
 161     table->count = 0;
 162     table->size = table->size*2;
 163     __CFUUID_t **oldPtrs = table->weakPtrs;
 164     table->weakPtrs = (__CFUUID_t **)MALLOC(sizeof(__CFUUID_t *)*table->size);
 165     for (int i = 0; i < table->size; ++i) table->weakPtrs[i] = (__CFUUID_t *)0x1;
 166     for (int i = 0; i < table->size / 2; ++i) {
 167         if (oldPtrs[i] == (__CFUUID_t *)0x1) continue; // available field, ignore
 168         if (oldPtrs[i] == NULL) continue;  // zero'ed by collector, ignore
 169         enter_has_lock((__CFUUID_t *)READWEAK(&oldPtrs[i]));  // read, then enter (but enter must check for NULL)
 170         WRITEWEAK(&oldPtrs[i], NULL);  // unregister
 171     }
 172     FREE(oldPtrs);
 173 }
 174
 175 /***** end of weak set */
 176
 177 static void __CFUUIDAddUniqueUUIDHasLock(CFUUIDRef uuid) {
 178     CFDictionaryKeyCallBacks __CFUUIDBytesDictionaryKeyCallBacks = {0, NULL, NULL, NULL, __CFisEqualUUIDBytes, __CFhashUUIDBytes};
 179     CFDictionaryValueCallBacks __CFnonRetainedUUIDDictionaryValueCallBacks = {0, NULL, NULL, CFCopyDescription, CFEqual};
 180
 181     if (kCFUseCollectableAllocator) {
 182         enter_has_lock((__CFUUID_t *)uuid);
 183         if (_UUIDWeakSet.count > (3 * _UUIDWeakSet.size / 4)) grow_has_lock();
 184     } else {
 185         if (!_uniquedUUIDs) _uniquedUUIDs = CFDictionaryCreateMutable(kCFAllocatorSystemDefault, 0, &__CFUUIDBytesDictionaryKeyCallBacks, &__CFnonRetainedUUIDDictionaryValueCallBacks);
 186         CFDictionarySetValue(_uniquedUUIDs, &(uuid->_bytes), uuid);
 187     }
 188 }
 189
 190 static void __CFUUIDRemoveUniqueUUIDHasLock(CFUUIDRef uuid) {
 191     if (_uniquedUUIDs) CFDictionaryRemoveValue(_uniquedUUIDs, &(uuid->_bytes));
 192 }
 193
 194 static CFUUIDRef __CFUUIDGetUniquedUUIDHasLock(const CFUUIDBytes *bytes) {
 195     CFUUIDRef uuid = NULL;
 196     if (kCFUseCollectableAllocator) {
 197         uuid = (CFUUIDRef)find_has_lock(bytes);
 198     } else if (_uniquedUUIDs) {
 199         uuid = (CFUUIDRef)CFDictionaryGetValue(_uniquedUUIDs, bytes);
 200     }
 201     return uuid;
 202 }
 203
 204 static void __CFUUIDDeallocate(CFTypeRef cf) {
 205     if (kCFUseCollectableAllocator) return;
 206
 207     __CFUUID_t *uuid = (__CFUUID_t *)cf;
 208     LOCKED(^{
 209     __CFUUIDRemoveUniqueUUIDHasLock(uuid);
 210     });
 211 }
 212
 213 static CFStringRef __CFUUIDCopyDescription(CFTypeRef cf) {
 214     CFStringRef uuidStr = CFUUIDCreateString(CFGetAllocator(cf), (CFUUIDRef)cf);
 215     CFStringRef desc = CFStringCreateWithFormat(kCFAllocatorSystemDefault, NULL, CFSTR("<CFUUID %p> %@"), cf, uuidStr);
 216     CFRelease(uuidStr);
 217     return desc;
 218 }
 219
 220 static CFStringRef __CFUUIDCopyFormattingDescription(CFTypeRef cf, CFDictionaryRef formatOptions) {
 221     return CFUUIDCreateString(CFGetAllocator(cf), (CFUUIDRef)cf);
 222 }
 223
 224 static CFTypeID __kCFUUIDTypeID = _kCFRuntimeNotATypeID;
 225
 226 static const CFRuntimeClass __CFUUIDClass = {
 227     0,
 228     "CFUUID",
 229     NULL,       // init
 230     NULL,       // copy
 231     __CFUUIDDeallocate,
 232     NULL,       // equal
 233     NULL,       // hash
 234     __CFUUIDCopyFormattingDescription,
 235     __CFUUIDCopyDescription
 236 };
 237
 238 CFTypeID CFUUIDGetTypeID(void) {
 239     static dispatch_once_t initOnce;
 240     dispatch_once(&initOnce, ^{ __kCFUUIDTypeID = _CFRuntimeRegisterClass(&__CFUUIDClass); });
 241     return __kCFUUIDTypeID;
 242 }
 243
 244 static CFUUIDRef __CFUUIDCreateWithBytesPrimitive(CFAllocatorRef allocator, CFUUIDBytes bytes, Boolean isConst) {
 245     __block __CFUUID_t *uuid = NULL;
 246     LOCKED(^{
 247         uuid = (__CFUUID_t *)__CFUUIDGetUniquedUUIDHasLock(&bytes);
 248         if (!uuid) {
 249             size_t size;
 250             size = sizeof(__CFUUID_t) - sizeof(CFRuntimeBase);
 251             uuid = (__CFUUID_t *)_CFRuntimeCreateInstance(kCFUseCollectableAllocator ? kCFAllocatorSystemDefault : allocator, CFUUIDGetTypeID(), size, NULL);
 252
 253             if (!uuid) return;
 254
 255             uuid->_bytes = bytes;
 256             __CFUUIDAddUniqueUUIDHasLock(uuid);
 257         } else if (!isConst) {
 258             CFRetain(uuid);
 259         }
 260     });
 261
 262     return (CFUUIDRef)uuid;
 263 }
 264
 265 #if DEPLOYMENT_TARGET_WINDOWS
 266 #include <Rpc.h>
 267 #elif DEPLOYMENT_TARGET_MACOSX || DEPLOYMENT_TARGET_EMBEDDED
 268 #include <uuid/uuid.h>
 269 #endif
 270
 271 CFUUIDRef CFUUIDCreate(CFAllocatorRef alloc) {
 272     /* Create a new bytes struct and then call the primitive. */
 273     __block CFUUIDBytes bytes;
 274     __block uint32_t retval = 0;
 275
 276     LOCKED(^{
 277 #if DEPLOYMENT_TARGET_WINDOWS
 278         UUID u;
 279         long rStatus = UuidCreate(&u);
 280         if (RPC_S_OK != rStatus && RPC_S_UUID_LOCAL_ONLY != rStatus) retval = 1;
 281         memmove(&bytes, &u, sizeof(bytes));
 282 #elif DEPLOYMENT_TARGET_MACOSX || DEPLOYMENT_TARGET_EMBEDDED
 283         static Boolean useV1UUIDs = false, checked = false;
 284         uuid_t uuid;
 285         if (!checked) {
 286             const char *value = __CFgetenv("CFUUIDVersionNumber");
 287             if (value) {
 288                 if (1 == strtoul_l(value, NULL, 0, NULL)) useV1UUIDs = true;
 289             }
 290             checked = true;
 291         }
 292         if (useV1UUIDs) uuid_generate_time(uuid); else uuid_generate_random(uuid);
 293         memcpy((void *)&bytes, uuid, sizeof(uuid));
 294 #else
 295         retval = 1;
 296 #endif
 297     });
 298
 299     return (retval == 0) ? __CFUUIDCreateWithBytesPrimitive(alloc, bytes, false) : NULL;
 300 }
 301
 302 CFUUIDRef CFUUIDCreateWithBytes(CFAllocatorRef alloc, uint8_t byte0, uint8_t byte1, uint8_t byte2, uint8_t byte3, uint8_t byte4, uint8_t byte5, uint8_t byte6, uint8_t byte7, uint8_t byte8, uint8_t byte9, uint8_t byte10, uint8_t byte11, uint8_t byte12, uint8_t byte13, uint8_t byte14, uint8_t byte15) {
 303     CFUUIDBytes bytes;
 304     // CodeWarrior can't handle the structure assignment of bytes, so we must explode this - REW, 10/8/99
 305     bytes.byte0 = byte0;
 306     bytes.byte1 = byte1;
 307     bytes.byte2 = byte2;
 308     bytes.byte3 = byte3;
 309     bytes.byte4 = byte4;
 310     bytes.byte5 = byte5;
 311     bytes.byte6 = byte6;
 312     bytes.byte7 = byte7;
 313     bytes.byte8 = byte8;
 314     bytes.byte9 = byte9;
 315     bytes.byte10 = byte10;
 316     bytes.byte11 = byte11;
 317     bytes.byte12 = byte12;
 318     bytes.byte13 = byte13;
 319     bytes.byte14 = byte14;
 320     bytes.byte15 = byte15;
 321
 322     return __CFUUIDCreateWithBytesPrimitive(alloc, bytes, false);
 323 }
 324
 325 static void _intToHexChars(UInt32 in, UniChar *out, int digits) {
 326     int shift;
 327     UInt32 d;
 328
 329     while (--digits >= 0) {
 330         shift = digits << 2;
 331         d = 0x0FL & (in >> shift);
 332         if (d <= 9) {
 333             *out++ = (UniChar)'0' + d;
 334         } else {
 335             *out++ = (UniChar)'A' + (d - 10);
 336         }
 337     }
 338 }
 339
 340 static uint8_t _byteFromHexChars(UniChar *in) {
 341     uint8_t result = 0;
 342     UniChar c;
 343     uint8_t d;
 344     CFIndex i;
 345
 346     for (i=0; i<2; i++) {
 347         c = in[i];
 348         if ((c >= (UniChar)'0') && (c <= (UniChar)'9')) {
 349             d = c - (UniChar)'0';
 350         } else if ((c >= (UniChar)'a') && (c <= (UniChar)'f')) {
 351             d = c - ((UniChar)'a' - 10);
 352         } else if ((c >= (UniChar)'A') && (c <= (UniChar)'F')) {
 353             d = c - ((UniChar)'A' - 10);
 354         } else {
 355             return 0;
 356         }
 357         result = (result << 4) | d;
 358     }
 359
 360     return result;
 361 }
 362
 363 CF_INLINE Boolean _isHexChar(UniChar c) {
 364     return ((((c >= (UniChar)'0') && (c <= (UniChar)'9')) || ((c >= (UniChar)'a') && (c <= (UniChar)'f')) || ((c >= (UniChar)'A') && (c <= (UniChar)'F'))) ? true : false);
 365 }
 366
 367 #define READ_A_BYTE(into) if (i+1 < len) { \
 368     (into) = _byteFromHexChars(&(chars[i])); \
 369         i+=2; \
 370 }
 371
 372 CFUUIDRef CFUUIDCreateFromString(CFAllocatorRef alloc, CFStringRef uuidStr) {
 373     /* Parse the string into a bytes struct and then call the primitive. */
 374     CFUUIDBytes bytes;
 375     UniChar chars[100];
 376     CFIndex len;
 377     CFIndex i = 0;
 378
 379     if (uuidStr == NULL) return NULL;
 380
 381     len = CFStringGetLength(uuidStr);
 382     if (len > 100) {
 383         len = 100;
 384     } else if (len == 0) {
 385         return NULL;
 386     }
 387     CFStringGetCharacters(uuidStr, CFRangeMake(0, len), chars);
 388     memset((void *)&bytes, 0, sizeof(bytes));
 389
 390     /* Skip initial random stuff */
 391     while (!_isHexChar(chars[i]) && i < len) i++;
 392
 393     READ_A_BYTE(bytes.byte0);
 394     READ_A_BYTE(bytes.byte1);
 395     READ_A_BYTE(bytes.byte2);
 396     READ_A_BYTE(bytes.byte3);
 397     i++;
 398
 399     READ_A_BYTE(bytes.byte4);
 400     READ_A_BYTE(bytes.byte5);
 401     i++;
 402
 403     READ_A_BYTE(bytes.byte6);
 404     READ_A_BYTE(bytes.byte7);
 405     i++;
 406
 407     READ_A_BYTE(bytes.byte8);
 408     READ_A_BYTE(bytes.byte9);
 409     i++;
 410
 411     READ_A_BYTE(bytes.byte10);
 412     READ_A_BYTE(bytes.byte11);
 413     READ_A_BYTE(bytes.byte12);
 414     READ_A_BYTE(bytes.byte13);
 415     READ_A_BYTE(bytes.byte14);
 416     READ_A_BYTE(bytes.byte15);
 417
 418     return __CFUUIDCreateWithBytesPrimitive(alloc, bytes, false);
 419 }
 420
 421 CFStringRef CFUUIDCreateString(CFAllocatorRef alloc, CFUUIDRef uuid) {
 422     CFMutableStringRef str = CFStringCreateMutable(alloc, 0);
 423     UniChar buff[12];
 424
 425     // First segment (4 bytes, 8 digits + 1 dash)
 426     _intToHexChars(uuid->_bytes.byte0, buff, 2);
 427     _intToHexChars(uuid->_bytes.byte1, &(buff[2]), 2);
 428     _intToHexChars(uuid->_bytes.byte2, &(buff[4]), 2);
 429     _intToHexChars(uuid->_bytes.byte3, &(buff[6]), 2);
 430     buff[8] = (UniChar)'-';
 431     CFStringAppendCharacters(str, buff, 9);
 432
 433     // Second segment (2 bytes, 4 digits + 1 dash)
 434     _intToHexChars(uuid->_bytes.byte4, buff, 2);
 435     _intToHexChars(uuid->_bytes.byte5, &(buff[2]), 2);
 436     buff[4] = (UniChar)'-';
 437     CFStringAppendCharacters(str, buff, 5);
 438
 439     // Third segment (2 bytes, 4 digits + 1 dash)
 440     _intToHexChars(uuid->_bytes.byte6, buff, 2);
 441     _intToHexChars(uuid->_bytes.byte7, &(buff[2]), 2);
 442     buff[4] = (UniChar)'-';
 443     CFStringAppendCharacters(str, buff, 5);
 444
 445     // Fourth segment (2 bytes, 4 digits + 1 dash)
 446     _intToHexChars(uuid->_bytes.byte8, buff, 2);
 447     _intToHexChars(uuid->_bytes.byte9, &(buff[2]), 2);
 448     buff[4] = (UniChar)'-';
 449     CFStringAppendCharacters(str, buff, 5);
 450
 451     // Fifth segment (6 bytes, 12 digits)
 452     _intToHexChars(uuid->_bytes.byte10, buff, 2);
 453     _intToHexChars(uuid->_bytes.byte11, &(buff[2]), 2);
 454     _intToHexChars(uuid->_bytes.byte12, &(buff[4]), 2);
 455     _intToHexChars(uuid->_bytes.byte13, &(buff[6]), 2);
 456     _intToHexChars(uuid->_bytes.byte14, &(buff[8]), 2);
 457     _intToHexChars(uuid->_bytes.byte15, &(buff[10]), 2);
 458     CFStringAppendCharacters(str, buff, 12);
 459
 460     return str;
 461 }
 462
 463 CFUUIDRef CFUUIDGetConstantUUIDWithBytes(CFAllocatorRef alloc, uint8_t byte0, uint8_t byte1, uint8_t byte2, uint8_t byte3, uint8_t byte4, uint8_t byte5, uint8_t byte6, uint8_t byte7, uint8_t byte8, uint8_t byte9, uint8_t byte10, uint8_t byte11, uint8_t byte12, uint8_t byte13, uint8_t byte14, uint8_t byte15) {
 464     CFUUIDBytes bytes;
 465     // CodeWarrior can't handle the structure assignment of bytes, so we must explode this - REW, 10/8/99
 466     bytes.byte0 = byte0;
 467     bytes.byte1 = byte1;
 468     bytes.byte2 = byte2;
 469     bytes.byte3 = byte3;
 470     bytes.byte4 = byte4;
 471     bytes.byte5 = byte5;
 472     bytes.byte6 = byte6;
 473     bytes.byte7 = byte7;
 474     bytes.byte8 = byte8;
 475     bytes.byte9 = byte9;
 476     bytes.byte10 = byte10;
 477     bytes.byte11 = byte11;
 478     bytes.byte12 = byte12;
 479     bytes.byte13 = byte13;
 480     bytes.byte14 = byte14;
 481     bytes.byte15 = byte15;
 482
 483     return __CFUUIDCreateWithBytesPrimitive(alloc, bytes, true);
 484 }
 485
 486 CFUUIDBytes CFUUIDGetUUIDBytes(CFUUIDRef uuid) {
 487     return uuid->_bytes;
 488 }
 489
 490 CF_EXPORT CFUUIDRef CFUUIDCreateFromUUIDBytes(CFAllocatorRef alloc, CFUUIDBytes bytes) {
 491     return __CFUUIDCreateWithBytesPrimitive(alloc, bytes, false);
 492 }
 493
 494 #undef READ_A_BYTE
 495