| /* |
| * Copyright (c) 1999-2003 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@ |
| */ |
| #ifndef _MACHO_NLIST_H_ |
| #define _MACHO_NLIST_H_ |
| /* $NetBSD: nlist.h,v 1.5 1994/10/26 00:56:11 cgd Exp $ */ |
| |
| /*- |
| * Copyright (c) 1991, 1993 |
| * The Regents of the University of California. All rights reserved. |
| * (c) UNIX System Laboratories, Inc. |
| * All or some portions of this file are derived from material licensed |
| * to the University of California by American Telephone and Telegraph |
| * Co. or Unix System Laboratories, Inc. and are reproduced herein with |
| * the permission of UNIX System Laboratories, Inc. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * 3. All advertising materials mentioning features or use of this software |
| * must display the following acknowledgement: |
| * This product includes software developed by the University of |
| * California, Berkeley and its contributors. |
| * 4. Neither the name of the University nor the names of its contributors |
| * may be used to endorse or promote products derived from this software |
| * without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
| * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
| * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| * SUCH DAMAGE. |
| * |
| * @(#)nlist.h 8.2 (Berkeley) 1/21/94 |
| */ |
| #include <stdint.h> |
| |
| /* |
| * Format of a symbol table entry of a Mach-O file for 32-bit architectures. |
| * Modified from the BSD format. The modifications from the original format |
| * were changing n_other (an unused field) to n_sect and the addition of the |
| * N_SECT type. These modifications are required to support symbols in a larger |
| * number of sections not just the three sections (text, data and bss) in a BSD |
| * file. |
| */ |
| struct nlist { |
| union { |
| #ifndef __LP64__ |
| char *n_name; /* for use when in-core */ |
| #endif |
| int32_t n_strx; /* index into the string table */ |
| } n_un; |
| uint8_t n_type; /* type flag, see below */ |
| uint8_t n_sect; /* section number or NO_SECT */ |
| int16_t n_desc; /* see <mach-o/stab.h> */ |
| uint32_t n_value; /* value of this symbol (or stab offset) */ |
| }; |
| |
| /* |
| * This is the symbol table entry structure for 64-bit architectures. |
| */ |
| struct nlist_64 { |
| union { |
| uint32_t n_strx; /* index into the string table */ |
| } n_un; |
| uint8_t n_type; /* type flag, see below */ |
| uint8_t n_sect; /* section number or NO_SECT */ |
| uint16_t n_desc; /* see <mach-o/stab.h> */ |
| uint64_t n_value; /* value of this symbol (or stab offset) */ |
| }; |
| |
| /* |
| * Symbols with a index into the string table of zero (n_un.n_strx == 0) are |
| * defined to have a null, "", name. Therefore all string indexes to non null |
| * names must not have a zero string index. This is bit historical information |
| * that has never been well documented. |
| */ |
| |
| /* |
| * The n_type field really contains four fields: |
| * unsigned char N_STAB:3, |
| * N_PEXT:1, |
| * N_TYPE:3, |
| * N_EXT:1; |
| * which are used via the following masks. |
| */ |
| #define N_STAB 0xe0 /* if any of these bits set, a symbolic debugging entry */ |
| #define N_PEXT 0x10 /* private external symbol bit */ |
| #define N_TYPE 0x0e /* mask for the type bits */ |
| #define N_EXT 0x01 /* external symbol bit, set for external symbols */ |
| |
| /* |
| * Only symbolic debugging entries have some of the N_STAB bits set and if any |
| * of these bits are set then it is a symbolic debugging entry (a stab). In |
| * which case then the values of the n_type field (the entire field) are given |
| * in <mach-o/stab.h> |
| */ |
| |
| /* |
| * Values for N_TYPE bits of the n_type field. |
| */ |
| #define N_UNDF 0x0 /* undefined, n_sect == NO_SECT */ |
| #define N_ABS 0x2 /* absolute, n_sect == NO_SECT */ |
| #define N_SECT 0xe /* defined in section number n_sect */ |
| #define N_PBUD 0xc /* prebound undefined (defined in a dylib) */ |
| #define N_INDR 0xa /* indirect */ |
| |
| /* |
| * If the type is N_INDR then the symbol is defined to be the same as another |
| * symbol. In this case the n_value field is an index into the string table |
| * of the other symbol's name. When the other symbol is defined then they both |
| * take on the defined type and value. |
| */ |
| |
| /* |
| * If the type is N_SECT then the n_sect field contains an ordinal of the |
| * section the symbol is defined in. The sections are numbered from 1 and |
| * refer to sections in order they appear in the load commands for the file |
| * they are in. This means the same ordinal may very well refer to different |
| * sections in different files. |
| * |
| * The n_value field for all symbol table entries (including N_STAB's) gets |
| * updated by the link editor based on the value of it's n_sect field and where |
| * the section n_sect references gets relocated. If the value of the n_sect |
| * field is NO_SECT then it's n_value field is not changed by the link editor. |
| */ |
| #define NO_SECT 0 /* symbol is not in any section */ |
| #define MAX_SECT 255 /* 1 thru 255 inclusive */ |
| |
| /* |
| * Common symbols are represented by undefined (N_UNDF) external (N_EXT) types |
| * who's values (n_value) are non-zero. In which case the value of the n_value |
| * field is the size (in bytes) of the common symbol. The n_sect field is set |
| * to NO_SECT. The alignment of a common symbol may be set as a power of 2 |
| * between 2^1 and 2^15 as part of the n_desc field using the macros below. If |
| * the alignment is not set (a value of zero) then natural alignment based on |
| * the size is used. |
| */ |
| #define GET_COMM_ALIGN(n_desc) (((n_desc) >> 8) & 0x0f) |
| #define SET_COMM_ALIGN(n_desc,align) \ |
| (n_desc) = (((n_desc) & 0xf0ff) | (((align) & 0x0f) << 8)) |
| |
| /* |
| * To support the lazy binding of undefined symbols in the dynamic link-editor, |
| * the undefined symbols in the symbol table (the nlist structures) are marked |
| * with the indication if the undefined reference is a lazy reference or |
| * non-lazy reference. If both a non-lazy reference and a lazy reference is |
| * made to the same symbol the non-lazy reference takes precedence. A reference |
| * is lazy only when all references to that symbol are made through a symbol |
| * pointer in a lazy symbol pointer section. |
| * |
| * The implementation of marking nlist structures in the symbol table for |
| * undefined symbols will be to use some of the bits of the n_desc field as a |
| * reference type. The mask REFERENCE_TYPE will be applied to the n_desc field |
| * of an nlist structure for an undefined symbol to determine the type of |
| * undefined reference (lazy or non-lazy). |
| * |
| * The constants for the REFERENCE FLAGS are propagated to the reference table |
| * in a shared library file. In that case the constant for a defined symbol, |
| * REFERENCE_FLAG_DEFINED, is also used. |
| */ |
| /* Reference type bits of the n_desc field of undefined symbols */ |
| #define REFERENCE_TYPE 0x7 |
| /* types of references */ |
| #define REFERENCE_FLAG_UNDEFINED_NON_LAZY 0 |
| #define REFERENCE_FLAG_UNDEFINED_LAZY 1 |
| #define REFERENCE_FLAG_DEFINED 2 |
| #define REFERENCE_FLAG_PRIVATE_DEFINED 3 |
| #define REFERENCE_FLAG_PRIVATE_UNDEFINED_NON_LAZY 4 |
| #define REFERENCE_FLAG_PRIVATE_UNDEFINED_LAZY 5 |
| |
| /* |
| * To simplify stripping of objects that use are used with the dynamic link |
| * editor, the static link editor marks the symbols defined an object that are |
| * referenced by a dynamicly bound object (dynamic shared libraries, bundles). |
| * With this marking strip knows not to strip these symbols. |
| */ |
| #define REFERENCED_DYNAMICALLY 0x0010 |
| |
| /* |
| * For images created by the static link editor with the -twolevel_namespace |
| * option in effect the flags field of the mach header is marked with |
| * MH_TWOLEVEL. And the binding of the undefined references of the image are |
| * determined by the static link editor. Which library an undefined symbol is |
| * bound to is recorded by the static linker in the high 8 bits of the n_desc |
| * field using the SET_LIBRARY_ORDINAL macro below. The ordinal recorded |
| * references the libraries listed in the Mach-O's LC_LOAD_DYLIB, |
| * LC_LOAD_WEAK_DYLIB, LC_REEXPORT_DYLIB, LC_LOAD_UPWARD_DYLIB, and |
| * LC_LAZY_LOAD_DYLIB, etc. load commands in the order they appear in the |
| * headers. The library ordinals start from 1. |
| * For a dynamic library that is built as a two-level namespace image the |
| * undefined references from module defined in another use the same nlist struct |
| * an in that case SELF_LIBRARY_ORDINAL is used as the library ordinal. For |
| * defined symbols in all images they also must have the library ordinal set to |
| * SELF_LIBRARY_ORDINAL. The EXECUTABLE_ORDINAL refers to the executable |
| * image for references from plugins that refer to the executable that loads |
| * them. |
| * |
| * The DYNAMIC_LOOKUP_ORDINAL is for undefined symbols in a two-level namespace |
| * image that are looked up by the dynamic linker with flat namespace semantics. |
| * This ordinal was added as a feature in Mac OS X 10.3 by reducing the |
| * value of MAX_LIBRARY_ORDINAL by one. So it is legal for existing binaries |
| * or binaries built with older tools to have 0xfe (254) dynamic libraries. In |
| * this case the ordinal value 0xfe (254) must be treated as a library ordinal |
| * for compatibility. |
| */ |
| #define GET_LIBRARY_ORDINAL(n_desc) (((n_desc) >> 8) & 0xff) |
| #define SET_LIBRARY_ORDINAL(n_desc,ordinal) \ |
| (n_desc) = (((n_desc) & 0x00ff) | (((ordinal) & 0xff) << 8)) |
| #define SELF_LIBRARY_ORDINAL 0x0 |
| #define MAX_LIBRARY_ORDINAL 0xfd |
| #define DYNAMIC_LOOKUP_ORDINAL 0xfe |
| #define EXECUTABLE_ORDINAL 0xff |
| |
| /* |
| * The bit 0x0020 of the n_desc field is used for two non-overlapping purposes |
| * and has two different symbolic names, N_NO_DEAD_STRIP and N_DESC_DISCARDED. |
| */ |
| |
| /* |
| * The N_NO_DEAD_STRIP bit of the n_desc field only ever appears in a |
| * relocatable .o file (MH_OBJECT filetype). And is used to indicate to the |
| * static link editor it is never to dead strip the symbol. |
| */ |
| #define N_NO_DEAD_STRIP 0x0020 /* symbol is not to be dead stripped */ |
| |
| /* |
| * The N_DESC_DISCARDED bit of the n_desc field never appears in linked image. |
| * But is used in very rare cases by the dynamic link editor to mark an in |
| * memory symbol as discared and longer used for linking. |
| */ |
| #define N_DESC_DISCARDED 0x0020 /* symbol is discarded */ |
| |
| /* |
| * The N_WEAK_REF bit of the n_desc field indicates to the dynamic linker that |
| * the undefined symbol is allowed to be missing and is to have the address of |
| * zero when missing. |
| */ |
| #define N_WEAK_REF 0x0040 /* symbol is weak referenced */ |
| |
| /* |
| * The N_WEAK_DEF bit of the n_desc field indicates to the static and dynamic |
| * linkers that the symbol definition is weak, allowing a non-weak symbol to |
| * also be used which causes the weak definition to be discared. Currently this |
| * is only supported for symbols in coalesed sections. |
| */ |
| #define N_WEAK_DEF 0x0080 /* coalesed symbol is a weak definition */ |
| |
| /* |
| * The N_REF_TO_WEAK bit of the n_desc field indicates to the dynamic linker |
| * that the undefined symbol should be resolved using flat namespace searching. |
| */ |
| #define N_REF_TO_WEAK 0x0080 /* reference to a weak symbol */ |
| |
| /* |
| * The N_ARM_THUMB_DEF bit of the n_desc field indicates that the symbol is |
| * a defintion of a Thumb function. |
| */ |
| #define N_ARM_THUMB_DEF 0x0008 /* symbol is a Thumb function (ARM) */ |
| |
| /* |
| * The N_SYMBOL_RESOLVER bit of the n_desc field indicates that the |
| * that the function is actually a resolver function and should |
| * be called to get the address of the real function to use. |
| * This bit is only available in .o files (MH_OBJECT filetype) |
| */ |
| #define N_SYMBOL_RESOLVER 0x0100 |
| |
| #ifndef __STRICT_BSD__ |
| #if __cplusplus |
| extern "C" { |
| #endif /* __cplusplus */ |
| /* |
| * The function nlist(3) from the C library. |
| */ |
| extern int nlist (const char *filename, struct nlist *list); |
| #if __cplusplus |
| } |
| #endif /* __cplusplus */ |
| #endif /* __STRICT_BSD__ */ |
| |
| #endif /* _MACHO_LIST_H_ */ |