runtime/objc-runtime.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-runtime.h
  27  *      Copyright 1988-1996, NeXT Software, Inc.
  28  */
  29
  30 #ifndef _OBJC_RUNTIME_H_
  31 #define _OBJC_RUNTIME_H_
  32
  33 #import <stdarg.h>
  34 #import <AvailabilityMacros.h>
  35 #import <objc/objc.h>
  36 #import <objc/objc-class.h>
  37
  38 #if !defined(AVAILABLE_MAC_OS_X_VERSION_10_3_AND_LATER)
  39     /* For 10.2 compatibility */
  40 #   define AVAILABLE_MAC_OS_X_VERSION_10_3_AND_LATER
  41 #endif
  42
  43 typedef struct objc_symtab *Symtab;
  44
  45 struct objc_symtab {
  46         unsigned long   sel_ref_cnt;
  47         SEL             *refs;
  48         unsigned short  cls_def_cnt;
  49         unsigned short  cat_def_cnt;
  50         void            *defs[1];       /* variable size */
  51 };
  52
  53 typedef struct objc_module *Module;
  54
  55 struct objc_module {
  56         unsigned long   version;
  57         unsigned long   size;
  58         const char      *name;
  59         Symtab          symtab;
  60 };
  61
  62 struct objc_super {
  63         id receiver;
  64 #ifndef __cplusplus
  65         Class class;
  66 #else
  67         Class super_class;
  68 #endif
  69 };
  70
  71 /*
  72  * Messaging Primitives (prototypes)
  73  */
  74
  75 OBJC_EXPORT id objc_getClass(const char *name);
  76 OBJC_EXPORT id objc_getMetaClass(const char *name);
  77 OBJC_EXPORT id objc_msgSend(id self, SEL op, ...);
  78 OBJC_EXPORT id objc_msgSendSuper(struct objc_super *super, SEL op, ...);
  79
  80
  81 /* Struct-returning Messaging Primitives (prototypes)
  82  *
  83  * For historical reasons, the prototypes for the struct-returning
  84  * messengers are unusual. The portable, correct way to call these functions
  85  * is to cast them to your desired return type first.
  86  *
  87  * For example, `NSRect result = [myNSView frame]` could be written as:
  88  *   NSRect (*msgSend_stret_fn)(id, SEL, ...) = (NSRect(*)(id, SEL, ...))objc_msgSend_stret;
  89  *   NSRect result = (*msgSend_stret_fn)(myNSView, @selector(frame));
  90  * or, without the function pointer:
  91  *   NSRect result = (*(NSRect(*)(id, SEL, ...))objc_msgSend_stret)(myNSView, @selector(frame));
  92  *
  93  * BE WARNED that these prototypes have changed in the past and will change
  94  * in the future. Code that uses a cast like the example above will be
  95  * unaffected.
  96  */
  97
  98 #if defined(__cplusplus)
  99   OBJC_EXPORT id objc_msgSend_stret(id self, SEL op, ...);
 100   OBJC_EXPORT id objc_msgSendSuper_stret(struct objc_super *super, SEL op, ...);
 101 #else
 102   OBJC_EXPORT void objc_msgSend_stret(void * stretAddr, id self, SEL op, ...);
 103   OBJC_EXPORT void objc_msgSendSuper_stret(void * stretAddr, struct objc_super *super, SEL op, ...);
 104 #endif
 105
 106
 107 /* Forwarding */
 108
 109 OBJC_EXPORT id objc_msgSendv(id self, SEL op, unsigned arg_size, marg_list arg_frame);
 110 OBJC_EXPORT void objc_msgSendv_stret(void * stretAddr, id self, SEL op, unsigned arg_size, marg_list arg_frame);
 111
 112 /*
 113     getting all the classes in the application...
 114
 115     int objc_getClassList(buffer, bufferLen)
 116         classes is an array of Class values (which are pointers)
 117                 which will be filled by the function; if this
 118                 argument is NULL, no copying is done, only the
 119                 return value is returned
 120         bufferLen is the number of Class values the given buffer
 121                 can hold; if the buffer is not large enough to
 122                 hold all the classes, the buffer is filled to
 123                 the indicated capacity with some arbitrary subset
 124                 of the known classes, which could be different
 125                 from call to call
 126         returns the number of classes, which is the number put
 127                 in the buffer if the buffer was large enough,
 128                 or the length the buffer should have been
 129
 130     int numClasses = 0, newNumClasses = objc_getClassList(NULL, 0);
 131     Class *classes = NULL;
 132     while (numClasses < newNumClasses) {
 133         numClasses = newNumClasses;
 134         classes = realloc(classes, sizeof(Class) * numClasses);
 135         newNumClasses = objc_getClassList(classes, numClasses);
 136     }
 137     // now, can use the classes list; if NULL, there are no classes
 138     free(classes);
 139
 140 */
 141 OBJC_EXPORT int objc_getClassList(Class *buffer, int bufferLen);
 142
 143 #define OBSOLETE_OBJC_GETCLASSES 1
 144 #if OBSOLETE_OBJC_GETCLASSES
 145 OBJC_EXPORT void *objc_getClasses(void);
 146 #endif
 147
 148 OBJC_EXPORT id objc_lookUpClass(const char *name);
 149 OBJC_EXPORT id objc_getRequiredClass(const char *name);
 150 OBJC_EXPORT void objc_addClass(Class myClass);
 151
 152 /* customizing the error handling for objc_getClass/objc_getMetaClass */
 153
 154 OBJC_EXPORT void objc_setClassHandler(int (*)(const char *));
 155
 156 /* Making the Objective-C runtime thread safe. */
 157 OBJC_EXPORT void objc_setMultithreaded (BOOL flag);
 158
 159 /* overriding the default object allocation and error handling routines */
 160
 161 OBJC_EXPORT id  (*_alloc)(Class, unsigned int);
 162 OBJC_EXPORT id  (*_copy)(id, unsigned int);
 163 OBJC_EXPORT id  (*_realloc)(id, unsigned int);
 164 OBJC_EXPORT id  (*_dealloc)(id);
 165 OBJC_EXPORT id  (*_zoneAlloc)(Class, unsigned int, void *);
 166 OBJC_EXPORT id  (*_zoneRealloc)(id, unsigned int, void *);
 167 OBJC_EXPORT id  (*_zoneCopy)(id, unsigned int, void *);
 168
 169 OBJC_EXPORT void        (*_error)(id, const char *, va_list);
 170
 171
 172 #endif /* _OBJC_RUNTIME_H_ */