/* * Copyright (c) 1999 Apple Computer, 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@ */ #include <mach-o/ldsyms.h> #include <string.h> #ifndef __OPENSTEP__ #include <crt_externs.h> #else /* defined(__OPENSTEP__) */ #ifdef __DYNAMIC__ #include "mach-o/dyld.h" /* defines _dyld_lookup_and_bind() */ #endif #if !defined(__DYNAMIC__) #define DECLARE_VAR(var, type) \ extern type var #define SETUP_VAR(var) #define USE_VAR(var) var #else #define STRINGIFY(a) # a #define DECLARE_VAR(var, type) \ static type * var ## _pointer = 0 #define SETUP_VAR(var) \ if ( var ## _pointer == 0) { \ _dyld_lookup_and_bind( STRINGIFY(_ ## var), \ (unsigned long *) & var ## _pointer, 0); \ } #define USE_VAR(var) (* var ## _pointer) #endif #endif /* __OPENSTEP__ */ /* * This routine returns the segment_command structure for the named segment if * it exist in the mach executible it is linked into. Otherwise it returns * zero. It uses the link editor defined symbol _mh_execute_header and just * looks through the load commands. Since these are mapped into the text * segment they are read only and thus const. */ const struct segment_command * getsegbyname( char *segname) { static struct mach_header *mhp = NULL; struct segment_command *sgp; unsigned long i; #ifndef __OPENSTEP__ if (mhp == NULL) { mhp = _NSGetMachExecuteHeader(); } #else /* defined(__OPENSTEP__) */ DECLARE_VAR(_mh_execute_header, struct mach_header); SETUP_VAR(_mh_execute_header); mhp = (struct mach_header *)(& USE_VAR(_mh_execute_header)); #endif /* __OPENSTEP__ */ sgp = (struct segment_command *) ((char *)mhp + sizeof(struct mach_header)); for(i = 0; i < mhp->ncmds; i++){ if(sgp->cmd == LC_SEGMENT) if(strncmp(sgp->segname, segname, sizeof(sgp->segname)) == 0) return(sgp); sgp = (struct segment_command *)((char *)sgp + sgp->cmdsize); } return((struct segment_command *)0); }