/*
* 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"
#if TARGET_IPHONE_SIMULATOR
// getsectiondata() not yet available
// 1. Find segment with file offset == 0 and file size != 0. This segment's
// contents span the Mach-O header. (File size of 0 is .bss, for example)
// 2. Slide is header's address - segment's preferred address
static ptrdiff_t
objc_getImageSlide(const struct mach_header *header)
{
unsigned long i;
const struct segment_command *sgp = (const struct segment_command *)(header + 1);
for (i = 0; i < header->ncmds; i++){
if (sgp->cmd == LC_SEGMENT) {
if (sgp->fileoff == 0 && sgp->filesize != 0) {
return (uintptr_t)header - (uintptr_t)sgp->vmaddr;
}
}
sgp = (const struct segment_command *)((char *)sgp + sgp->cmdsize);
}
// uh-oh
_objc_fatal("could not calculate VM slide for image");
return 0; // not reached
}
PRIVATE_EXTERN uint8_t *
objc_getsectiondata(const struct mach_header *mh, const char *segname, const char *sectname, unsigned long *outSize)
{
uint32_t size = 0;
char *data = getsectdatafromheader(mh, segname, sectname, &size);
if (data) {
*outSize = size;
return (uint8_t *)data + objc_getImageSlide(mh);
} else {
*outSize = 0;
return NULL;
}
}
static const struct segment_command *
objc_getsegbynamefromheader(const mach_header *head, const char *segname)
{
const struct segment_command *sgp;
unsigned long i;
sgp = (const struct segment_command *) (head + 1);
for (i = 0; i < head->ncmds; i++){
if (sgp->cmd == LC_SEGMENT) {
if (strncmp(sgp->segname, segname, sizeof(sgp->segname)) == 0) {
return sgp;
}
}
sgp = (const struct segment_command *)((char *)sgp + sgp->cmdsize);
}
return NULL;
}
PRIVATE_EXTERN uint8_t *
objc_getsegmentdata(const struct mach_header *mh, const char *segname, unsigned long *outSize)
{
const struct segment_command *seg;
seg = objc_getsegbynamefromheader(mh, segname);
if (seg) {
*outSize = seg->vmsize;
return (uint8_t *)seg->vmaddr + objc_getImageSlide(mh);
} else {
*outSize = 0;
return NULL;
}
}
// TARGET_IPHONE_SIMULATOR
#endif
#define GETSECT(name, type, sectname) \
PRIVATE_EXTERN 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_t *, "__objc_classrefs");
GETSECT(_getObjc2SuperRefs, class_t *, "__objc_superrefs");
GETSECT(_getObjc2ClassList, class_t *, "__objc_classlist");
GETSECT(_getObjc2NonlazyClassList, class_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");
PRIVATE_EXTERN 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;
}
PRIVATE_EXTERN 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