objc-file.mm   [plain text]


/*
 * Copyright (c) 1999-2007 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@
 */

#if __OBJC2__

#include "objc-private.h"
#include "objc-file.h"

#define GETSECT(name, type, sectname)                                   \
    type *name(const header_info *hi, size_t *outCount)  \
    {                                                                   \
        unsigned long byteCount = 0;                                    \
        type *data = (type *)                                           \
            getsectiondata(hi->mhdr, SEG_DATA, sectname, &byteCount);   \
        *outCount = byteCount / sizeof(type);                           \
        return data;                                                    \
    }

//      function name                 content type     section name
GETSECT(_getObjc2SelectorRefs,        SEL,             "__objc_selrefs"); 
GETSECT(_getObjc2MessageRefs,         message_ref_t,   "__objc_msgrefs"); 
GETSECT(_getObjc2ClassRefs,           Class,       "__objc_classrefs");
GETSECT(_getObjc2SuperRefs,           Class,       "__objc_superrefs");
GETSECT(_getObjc2ClassList,           classref_t,       "__objc_classlist");
GETSECT(_getObjc2NonlazyClassList,    classref_t,       "__objc_nlclslist");
GETSECT(_getObjc2CategoryList,        category_t *,    "__objc_catlist");
GETSECT(_getObjc2NonlazyCategoryList, category_t *,    "__objc_nlcatlist");
GETSECT(_getObjc2ProtocolList,        protocol_t *,    "__objc_protolist");
GETSECT(_getObjc2ProtocolRefs,        protocol_t *,    "__objc_protorefs");


objc_image_info *
_getObjcImageInfo(const headerType *mhdr, size_t *outBytes)
{
    unsigned long byteCount = 0;
    objc_image_info *data = (objc_image_info *)
        getsectiondata(mhdr, SEG_DATA, "__objc_imageinfo", &byteCount);
    *outBytes = byteCount;
    return data;
}


static const segmentType *
getsegbynamefromheader(const headerType *head, const char *segname)
{
    const segmentType *sgp;
    unsigned long i;
    
    sgp = (const segmentType *) (head + 1);
    for (i = 0; i < head->ncmds; i++){
        if (sgp->cmd == SEGMENT_CMD) {
            if (strncmp(sgp->segname, segname, sizeof(sgp->segname)) == 0) {
                return sgp;
            }
        }
        sgp = (const segmentType *)((char *)sgp + sgp->cmdsize);
    }
    return NULL;
}

BOOL
_hasObjcContents(const header_info *hi)
{
    // Look for a __DATA,__objc* section other than __DATA,__objc_imageinfo
    const segmentType *seg = getsegbynamefromheader(hi->mhdr, "__DATA");
    if (!seg) return NO;

    const sectionType *sect;
    uint32_t i;
    for (i = 0; i < seg->nsects; i++) {
        sect = ((const sectionType *)(seg+1))+i;
        if (0 == strncmp(sect->sectname, "__objc_", 7)  &&  
            0 != strncmp(sect->sectname, "__objc_imageinfo", 16)) 
        {
            return YES;
        }
    }

    return NO;
}

#endif