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Diffstat (limited to 'src/third_party/mac_headers/mach-o/nlist.h')
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1 files changed, 312 insertions, 0 deletions
diff --git a/src/third_party/mac_headers/mach-o/nlist.h b/src/third_party/mac_headers/mach-o/nlist.h new file mode 100644 index 00000000..1c194101 --- /dev/null +++ b/src/third_party/mac_headers/mach-o/nlist.h @@ -0,0 +1,312 @@ +/* + * 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_ */ |