study_objc4/objc4-779.1/runtime/objc-file.h

/*
 * Copyright (c) 2009 Apple Inc.  All Rights Reserved.
 * 
 * @APPLE_LICENSE_HEADER_START@
 * 
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this
 * file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 * 
 * @APPLE_LICENSE_HEADER_END@
 */

#ifndef _OBJC_FILE_NEW_H
#define _OBJC_FILE_NEW_H

#if __OBJC2__

#include "objc-runtime-new.h"

// classref_t is not fixed up at launch; use remapClass() to convert

// classlist and catlist and protolist sections are marked const here
// because those sections may be in read-only __DATA_CONST segments.

extern SEL *_getObjc2SelectorRefs(const header_info *hi, size_t *count);
extern message_ref_t *_getObjc2MessageRefs(const header_info *hi, size_t *count);
extern Class*_getObjc2ClassRefs(const header_info *hi, size_t *count);
extern Class*_getObjc2SuperRefs(const header_info *hi, size_t *count);
extern classref_t const *_getObjc2ClassList(const header_info *hi, size_t *count);
extern classref_t const *_getObjc2NonlazyClassList(const header_info *hi, size_t *count);
extern category_t * const *_getObjc2CategoryList(const header_info *hi, size_t *count);
extern category_t * const *_getObjc2CategoryList2(const header_info *hi, size_t *count);
extern category_t * const *_getObjc2NonlazyCategoryList(const header_info *hi, size_t *count);
extern protocol_t * const *_getObjc2ProtocolList(const header_info *hi, size_t *count);
extern protocol_t **_getObjc2ProtocolRefs(const header_info *hi, size_t *count);

// FIXME: rdar://29241917&33734254 clang doesn't sign static initializers.
struct UnsignedInitializer {
private:
    uintptr_t storage;
public:
    void operator () () const {
        using Initializer = void(*)();
        Initializer init =
            ptrauth_sign_unauthenticated((Initializer)storage,
                                         ptrauth_key_function_pointer, 0);
        init();
    }
};

extern UnsignedInitializer *getLibobjcInitializers(const header_info *hi, size_t *count);

extern classref_t const *_getObjc2NonlazyClassList(const headerType *mhdr, size_t *count);
extern category_t * const *_getObjc2NonlazyCategoryList(const headerType *mhdr, size_t *count);
extern UnsignedInitializer *getLibobjcInitializers(const headerType *mhdr, size_t *count);

static inline void
foreach_data_segment(const headerType *mhdr,
                     std::function<void(const segmentType *, intptr_t slide)> code)
{
    intptr_t slide = 0;

    // compute VM slide
    const segmentType *seg = (const segmentType *) (mhdr + 1);
    for (unsigned long i = 0; i < mhdr->ncmds; i++) {
        if (seg->cmd == SEGMENT_CMD  &&
            segnameEquals(seg->segname, "__TEXT"))
        {
            slide = (char *)mhdr - (char *)seg->vmaddr;
            break;
        }
        seg = (const segmentType *)((char *)seg + seg->cmdsize);
    }

    // enumerate __DATA* segments
    seg = (const segmentType *) (mhdr + 1);
    for (unsigned long i = 0; i < mhdr->ncmds; i++) {
        if (seg->cmd == SEGMENT_CMD  &&
            segnameStartsWith(seg->segname, "__DATA"))
        {
            code(seg, slide);
        }
        seg = (const segmentType *)((char *)seg + seg->cmdsize);
    }
}

#endif

#endif