runtime/objc-private.h

   1 /*
   2  * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
   7  *
   8  * This file contains Original Code and/or Modifications of Original Code
   9  * as defined in and that are subject to the Apple Public Source License
  10  * Version 2.0 (the 'License'). You may not use this file except in
  11  * compliance with the License. Please obtain a copy of the License at
  12  * http://www.opensource.apple.com/apsl/ and read it before using this
  13  * file.
  14  *
  15  * The Original Code and all software distributed under the License are
  16  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  17  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  18  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  20  * Please see the License for the specific language governing rights and
  21  * limitations under the License.
  22  *
  23  * @APPLE_LICENSE_HEADER_END@
  24  */
  25 /*
  26  *      objc-private.h
  27  *      Copyright 1988-1996, NeXT Software, Inc.
  28  */
  29
  30 #if !defined(_OBJC_PRIVATE_H_)
  31     #define _OBJC_PRIVATE_H_
  32
  33     #import <objc/objc-api.h>   // for OBJC_EXPORT
  34
  35     OBJC_EXPORT void checkUniqueness();
  36
  37     #import "objc-config.h"
  38
  39     #import <pthread.h>
  40     #define     mutex_alloc()   (pthread_mutex_t*)calloc(1, sizeof(pthread_mutex_t))
  41     #define     mutex_init(m)   pthread_mutex_init(m, NULL)
  42     #define     mutex_lock(m)   pthread_mutex_lock(m)
  43     #define     mutex_try_lock(m) (! pthread_mutex_trylock(m))
  44     #define     mutex_unlock(m) pthread_mutex_unlock(m)
  45     #define     mutex_clear(m)
  46     #define     mutex_t         pthread_mutex_t*
  47     #define mutex               MUTEX_DEFINE_ERROR
  48     #import <sys/time.h>
  49
  50     #import <stdlib.h>
  51     #import <stdarg.h>
  52     #import <stdio.h>
  53     #import <string.h>
  54     #import <ctype.h>
  55
  56     #import <objc/objc-runtime.h>
  57
  58     #import <malloc/malloc.h>
  59
  60
  61 /* Opaque cookie used in _getObjc... routines.  File format independant.
  62  * This is used in place of the mach_header.  In fact, when compiling
  63  * for NEXTSTEP, this is really a (struct mach_header *).
  64  *
  65  * had been: typedef void *objc_header;
  66  */
  67 #import <mach-o/loader.h>
  68 typedef struct mach_header headerType;
  69
  70 #import <objc/Protocol.h>
  71
  72 typedef struct _ProtocolTemplate { @defs(Protocol) } ProtocolTemplate;
  73 typedef struct _NXConstantStringTemplate {
  74     Class isa;
  75     void *characters;
  76     unsigned int _length;
  77 } NXConstantStringTemplate;
  78
  79 #define OBJC_CONSTANT_STRING_PTR NXConstantStringTemplate*
  80 #define OBJC_CONSTANT_STRING_DEREF &
  81 #define OBJC_PROTOCOL_PTR ProtocolTemplate*
  82 #define OBJC_PROTOCOL_DEREF .
  83
  84 typedef struct {
  85     uint32_t version; // currently 0
  86     uint32_t flags;
  87 } objc_image_info;
  88
  89 // masks for objc_image_info.flags
  90 #define OBJC_IMAGE_IS_REPLACEMENT (1<<0)
  91 #define _objcHeaderIsReplacement(h)  ((h)->info  &&  ((h)->info->flags & OBJC_IMAGE_IS_REPLACEMENT))
  92
  93 /* OBJC_IMAGE_IS_REPLACEMENT:
  94    Don't load any classes
  95    Don't load any categories
  96    Do fix up selector refs (@selector points to them)
  97    Do fix up class refs (@class and objc_msgSend points to them)
  98    Do fix up protocols (@protocol points to them)
  99    Future: do load new classes?
 100    Future: do load new categories?
 101    Future: do insert new methods on existing classes?
 102    Future: do insert new methods on existing categories?
 103 */
 104
 105
 106 // both
 107 OBJC_EXPORT headerType **       _getObjcHeaders();
 108 OBJC_EXPORT Module              _getObjcModules(headerType *head, int *nmodules);
 109 OBJC_EXPORT Class *             _getObjcClassRefs(headerType *head, int *nclasses);
 110 OBJC_EXPORT void *              _getObjcHeaderData(const headerType *head, unsigned *size);
 111 OBJC_EXPORT const char *        _getObjcHeaderName(headerType *head);
 112 OBJC_EXPORT objc_image_info *   _getObjcImageInfo(headerType *head);
 113
 114 // internal routines for delaying binding
 115 void _objc_resolve_categories_for_class (struct objc_class * cls);
 116 void _objc_bindClassIfNeeded(struct objc_class *cls);
 117 void _objc_bindModuleContainingClass(struct objc_class * cls);
 118
 119 // someday a logging facility
 120 // ObjC is assigned the range 0xb000 - 0xbfff for first parameter
 121 #define trace(a, b, c, d) do {} while (0)
 122
 123
 124
 125 OBJC_EXPORT ProtocolTemplate * _getObjcProtocols(headerType *head, int *nprotos);
 126 OBJC_EXPORT NXConstantStringTemplate *_getObjcStringObjects(headerType *head, int *nstrs);
 127 OBJC_EXPORT SEL *               _getObjcMessageRefs(headerType *head, int *nmess);
 128
 129 #define END_OF_METHODS_LIST ((struct objc_method_list*)-1)
 130
 131     typedef struct _header_info
 132     {
 133       const headerType *        mhdr;
 134       Module                    mod_ptr; // NOT adjusted by image_slide
 135       unsigned int              mod_count;
 136       unsigned long             image_slide;
 137       void *                    objcData;     // getObjcHeaderData result
 138       unsigned                  objcDataSize; // getObjcHeaderData result
 139       objc_image_info *         info;    // IS adjusted by image_slide
 140       struct _header_info *     next;
 141     } header_info;
 142     OBJC_EXPORT header_info *_objc_headerStart ();
 143
 144     OBJC_EXPORT int _objcModuleCount();
 145     OBJC_EXPORT const char *_objcModuleNameAtIndex(int i);
 146     OBJC_EXPORT Class objc_getOrigClass (const char *name);
 147
 148     extern struct objc_method_list **get_base_method_list(Class cls);
 149
 150
 151     OBJC_EXPORT const char *__S(_nameForHeader) (const headerType*);
 152
 153     /* initialize */
 154     OBJC_EXPORT void _sel_resolve_conflicts(headerType * header, unsigned long slide);
 155     OBJC_EXPORT void _class_install_relationships(Class, long);
 156     OBJC_EXPORT void *_objc_create_zone(void);
 157
 158     OBJC_EXPORT SEL sel_registerNameNoCopyNoLock(const char *str);
 159     OBJC_EXPORT void sel_lock(void);
 160     OBJC_EXPORT void sel_unlock(void);
 161
 162     /* selector fixup in method lists */
 163
 164     #define _OBJC_FIXED_UP ((void *)1771)
 165
 166     static inline struct objc_method_list *_objc_inlined_fixup_selectors_in_method_list(struct objc_method_list *mlist)
 167     {
 168         unsigned i, size;
 169         Method method;
 170         struct objc_method_list *old_mlist;
 171
 172         if ( ! mlist ) return (struct objc_method_list *)0;
 173         if ( mlist->obsolete != _OBJC_FIXED_UP ) {
 174             old_mlist = mlist;
 175             size = sizeof(struct objc_method_list) - sizeof(struct objc_method) + old_mlist->method_count * sizeof(struct objc_method);
 176             mlist = malloc_zone_malloc(_objc_create_zone(), size);
 177             memmove(mlist, old_mlist, size);
 178             sel_lock();
 179             for ( i = 0; i < mlist->method_count; i += 1 ) {
 180                 method = &mlist->method_list[i];
 181                 method->method_name =
 182                     sel_registerNameNoCopyNoLock((const char *)method->method_name);
 183             }
 184             sel_unlock();
 185             mlist->obsolete = _OBJC_FIXED_UP;
 186         }
 187         return mlist;
 188     }
 189
 190     /* method lookup */
 191     /* --  inline version of class_nextMethodList(Class, void **)  -- */
 192
 193     static inline struct objc_method_list *_class_inlinedNextMethodList(Class cls, void **it)
 194     {
 195         struct objc_method_list ***iterator;
 196
 197         iterator = (struct objc_method_list***)it;
 198         if (*iterator == NULL) {
 199             *iterator = &((((struct objc_class *) cls)->methodLists)[0]);
 200         }
 201         else (*iterator) += 1;
 202         // Check for list end
 203         if ((**iterator == NULL) || (**iterator == END_OF_METHODS_LIST)) {
 204             *it = nil;
 205             return NULL;
 206         }
 207
 208         **iterator = _objc_inlined_fixup_selectors_in_method_list(**iterator);
 209
 210         // Return method list pointer
 211         return **iterator;
 212     }
 213
 214     OBJC_EXPORT BOOL class_respondsToMethod(Class, SEL);
 215     OBJC_EXPORT IMP class_lookupMethod(Class, SEL);
 216     OBJC_EXPORT IMP class_lookupMethodInMethodList(struct objc_method_list *mlist, SEL sel);
 217     OBJC_EXPORT IMP class_lookupNamedMethodInMethodList(struct objc_method_list *mlist, const char *meth_name);
 218     OBJC_EXPORT void _objc_insertMethods( struct objc_method_list *mlist, struct objc_method_list ***list );
 219     OBJC_EXPORT void _objc_removeMethods( struct objc_method_list *mlist, struct objc_method_list ***list );
 220
 221     OBJC_EXPORT IMP _cache_getImp(Class cls, SEL sel);
 222     OBJC_EXPORT Method _cache_getMethod(Class cls, SEL sel, IMP objc_msgForward_imp);
 223
 224     /* message dispatcher */
 225     OBJC_EXPORT IMP _class_lookupMethodAndLoadCache(Class, SEL);
 226     OBJC_EXPORT id _objc_msgForward (id self, SEL sel, ...);
 227
 228     /* errors */
 229     OBJC_EXPORT volatile void _objc_fatal(const char *fmt, ...);
 230     OBJC_EXPORT volatile void _objc_error(id, const char *, va_list);
 231     OBJC_EXPORT volatile void __objc_error(id, const char *, ...);
 232     OBJC_EXPORT void _objc_inform(const char *fmt, ...);
 233     OBJC_EXPORT void _objc_syslog(const char *fmt, ...);
 234
 235     /* magic */
 236     OBJC_EXPORT Class _objc_getFreedObjectClass (void);
 237     OBJC_EXPORT const struct objc_cache emptyCache;
 238     OBJC_EXPORT void _objc_flush_caches (Class cls);
 239
 240     /* locking */
 241     #define MUTEX_TYPE pthread_mutex_t*
 242     #define OBJC_DECLARE_LOCK(MTX) pthread_mutex_t MTX = PTHREAD_MUTEX_INITIALIZER
 243     OBJC_EXPORT pthread_mutex_t classLock;
 244
 245     /* nil handler object */
 246     OBJC_EXPORT id _objc_nilReceiver;
 247     OBJC_EXPORT id _objc_setNilReceiver(id newNilReceiver);
 248     OBJC_EXPORT id _objc_getNilReceiver(void);
 249
 250
 251     typedef struct {
 252        long addressOffset;
 253        long selectorOffset;
 254     } FixupEntry;
 255
 256     static inline int selEqual( SEL s1, SEL s2 ) {
 257        return (s1 == s2);
 258     }
 259
 260     #define OBJC_LOCK(MUTEX)    mutex_lock (MUTEX)
 261     #define OBJC_UNLOCK(MUTEX)  mutex_unlock (MUTEX)
 262     #define OBJC_TRYLOCK(MUTEX) mutex_try_lock (MUTEX)
 263
 264 #if !defined(SEG_OBJC)
 265 #define SEG_OBJC        "__OBJC"        /* objective-C runtime segment */
 266 #endif
 267
 268
 269
 270
 271 static __inline__ int _objc_strcmp(const unsigned char *s1, const unsigned char *s2) {
 272     unsigned char c1, c2;
 273     for ( ; (c1 = *s1) == (c2 = *s2); s1++, s2++)
 274         if (c1 == '\0')
 275             return 0;
 276     return (c1 - c2);
 277 }
 278
 279 static __inline__ unsigned int _objc_strhash(const unsigned char *s) {
 280     unsigned int hash = 0;
 281     for (;;) {
 282         int a = *s++;
 283         if (0 == a) break;
 284         hash += (hash << 8) + a;
 285     }
 286     return hash;
 287 }
 288
 289
 290 // objc per-thread storage
 291 OBJC_EXPORT pthread_key_t _objc_pthread_key;
 292 typedef struct {
 293     struct _objc_initializing_classes *initializingClasses; // for +initialize
 294
 295     // If you add new fields here, don't forget to update
 296     // _objc_pthread_destroyspecific()
 297
 298 } _objc_pthread_data;
 299
 300
 301 // Class state
 302 #define ISCLASS(cls)            ((((struct objc_class *) cls)->info & CLS_CLASS) != 0)
 303 #define ISMETA(cls)             ((((struct objc_class *) cls)->info & CLS_META) != 0)
 304 #define GETMETA(cls)            (ISMETA(cls) ? ((struct objc_class *) cls) : ((struct objc_class *) cls)->isa)
 305 #define ISINITIALIZED(cls)      ((((volatile long)GETMETA(cls)->info) & CLS_INITIALIZED) != 0)
 306 #define ISINITIALIZING(cls)     ((((volatile long)GETMETA(cls)->info) & CLS_INITIALIZING) != 0)
 307
 308
 309 #endif /* _OBJC_PRIVATE_H_ */
 310