• Home
  • History
  • Annotate
  • Line#
  • Navigate
  • Raw
  • Download
  • only in /asuswrt-rt-n18u-9.0.0.4.380.2695/release/src-rt-6.x.4708/toolchains/hndtools-arm-linux-2.6.36-uclibc-4.5.3/arm-brcm-linux-uclibcgnueabi/sysroot/usr/include/
1/* Data structure for communication from the run-time dynamic linker for
2   loaded ELF shared objects.
3   Copyright (C) 1995-2001, 2004, 2005, 2006, 2010 Free Software Foundation, Inc.
4   This file is part of the GNU C Library.
5
6   The GNU C Library is free software; you can redistribute it and/or
7   modify it under the terms of the GNU Lesser General Public
8   License as published by the Free Software Foundation; either
9   version 2.1 of the License, or (at your option) any later version.
10
11   The GNU C Library is distributed in the hope that it will be useful,
12   but WITHOUT ANY WARRANTY; without even the implied warranty of
13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14   Lesser General Public License for more details.
15
16   You should have received a copy of the GNU Lesser General Public
17   License along with the GNU C Library; if not, write to the Free
18   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
19   02111-1307 USA.  */
20
21#ifndef	_LINK_H
22#define	_LINK_H	1
23
24#include <features.h>
25#include <elf.h>
26#ifdef __HAVE_SHARED__
27#include <dlfcn.h>
28#endif
29#include <sys/types.h>
30
31/* We use this macro to refer to ELF types independent of the native wordsize.
32   `ElfW(TYPE)' is used in place of `Elf32_TYPE' or `Elf64_TYPE'.  */
33#define ElfW(type)	_ElfW (Elf, __ELF_NATIVE_CLASS, type)
34#define _ElfW(e,w,t)	_ElfW_1 (e, w, _##t)
35#define _ElfW_1(e,w,t)	e##w##t
36
37#include <bits/elfclass.h>		/* Defines __ELF_NATIVE_CLASS.  */
38
39/* Rendezvous structure used by the run-time dynamic linker to communicate
40   details of shared object loading to the debugger.  If the executable's
41   dynamic section has a DT_DEBUG element, the run-time linker sets that
42   element's value to the address where this structure can be found.  */
43
44struct r_debug
45  {
46    int r_version;		/* Version number for this protocol.  */
47
48    struct link_map *r_map;	/* Head of the chain of loaded objects.  */
49
50    /* This is the address of a function internal to the run-time linker,
51       that will always be called when the linker begins to map in a
52       library or unmap it, and again when the mapping change is complete.
53       The debugger can set a breakpoint at this address if it wants to
54       notice shared object mapping changes.  */
55    ElfW(Addr) r_brk;
56    enum
57      {
58	/* This state value describes the mapping change taking place when
59	   the `r_brk' address is called.  */
60	RT_CONSISTENT,		/* Mapping change is complete.  */
61	RT_ADD,			/* Beginning to add a new object.  */
62	RT_DELETE		/* Beginning to remove an object mapping.  */
63      } r_state;
64
65    ElfW(Addr) r_ldbase;	/* Base address the linker is loaded at.  */
66  };
67
68/* This is the instance of that structure used by the dynamic linker.  */
69extern struct r_debug _r_debug;
70
71/* This symbol refers to the "dynamic structure" in the `.dynamic' section
72   of whatever module refers to `_DYNAMIC'.  So, to find its own
73   `struct r_debug', a program could do:
74     for (dyn = _DYNAMIC; dyn->d_tag != DT_NULL; ++dyn)
75       if (dyn->d_tag == DT_DEBUG)
76	 r_debug = (struct r_debug *) dyn->d_un.d_ptr;
77   */
78extern ElfW(Dyn) _DYNAMIC[];
79
80#ifdef __FDPIC__
81# include <bits/elf-fdpic.h>
82#endif
83#ifdef __DSBT__
84# include <bits/elf-dsbt.h>
85#endif
86
87/* Structure describing a loaded shared object.  The `l_next' and `l_prev'
88   members form a chain of all the shared objects loaded at startup.
89
90   These data structures exist in space used by the run-time dynamic linker;
91   modifying them may have disastrous results.  */
92
93struct link_map
94  {
95    /* These first few members are part of the protocol with the debugger.
96       This is the same format used in SVR4.  */
97
98#ifdef __FDPIC__
99    struct elf32_fdpic_loadaddr l_addr;
100#else
101#ifdef __DSBT__
102    struct elf32_dsbt_loadaddr l_addr;
103#else
104    ElfW(Addr) l_addr;		/* Base address shared object is loaded at.  */
105#endif
106#endif
107    char *l_name;		/* Absolute file name object was found in.  */
108    ElfW(Dyn) *l_ld;		/* Dynamic section of the shared object.  */
109    struct link_map *l_next, *l_prev; /* Chain of loaded objects.  */
110
111#if defined(USE_TLS) && USE_TLS
112    /* Thread-local storage related info.  */
113
114    /* Start of the initialization image.  */
115    void *l_tls_initimage;
116    /* Size of the initialization image.  */
117    size_t l_tls_initimage_size;
118    /* Size of the TLS block.  */
119    size_t l_tls_blocksize;
120    /* Alignment requirement of the TLS block.  */
121    size_t l_tls_align;
122    /* Offset of first byte module alignment.  */
123    size_t l_tls_firstbyte_offset;
124# ifndef NO_TLS_OFFSET
125#  define NO_TLS_OFFSET	0
126# endif
127    /* For objects present at startup time: offset in the static TLS block.  */
128    ptrdiff_t l_tls_offset;
129    /* Index of the module in the dtv array.  */
130    size_t l_tls_modid;
131    /* Nonzero if _dl_init_static_tls should be called for this module */
132    unsigned int l_need_tls_init:1;
133#endif
134  };
135
136#ifdef __USE_GNU
137
138#if 0
139/* Version numbers for la_version handshake interface.  */
140#define LAV_CURRENT	1
141
142/* Activity types signaled through la_activity.  */
143enum
144  {
145    LA_ACT_CONSISTENT,		/* Link map consistent again.  */
146    LA_ACT_ADD,			/* New object will be added.  */
147    LA_ACT_DELETE		/* Objects will be removed.  */
148  };
149
150/* Values representing origin of name for dynamic loading.  */
151enum
152  {
153    LA_SER_ORIG = 0x01,		/* Original name.  */
154    LA_SER_LIBPATH = 0x02,	/* Directory from LD_LIBRARY_PATH.  */
155    LA_SER_RUNPATH = 0x04,	/* Directory from RPATH/RUNPATH.  */
156    LA_SER_CONFIG = 0x08,	/* Found through ldconfig.  */
157    LA_SER_DEFAULT = 0x40,	/* Default directory.  */
158    LA_SER_SECURE = 0x80	/* Unused.  */
159  };
160
161/* Values for la_objopen return value.  */
162enum
163  {
164    LA_FLG_BINDTO = 0x01,	/* Audit symbols bound to this object.  */
165    LA_FLG_BINDFROM = 0x02	/* Audit symbols bound from this object.  */
166  };
167
168/* Values for la_symbind flags parameter.  */
169enum
170  {
171    LA_SYMB_NOPLTENTER = 0x01,	/* la_pltenter will not be called.  */
172    LA_SYMB_NOPLTEXIT = 0x02,	/* la_pltexit will not be called.  */
173    LA_SYMB_STRUCTCALL = 0x04,	/* Return value is a structure.  */
174    LA_SYMB_DLSYM = 0x08,	/* Binding due to dlsym call.  */
175    LA_SYMB_ALTVALUE = 0x10	/* Value has been changed by a previous
176				   la_symbind call.  */
177  };
178#endif
179
180struct dl_phdr_info
181  {
182#ifdef __FDPIC__
183    struct elf32_fdpic_loadaddr dlpi_addr;
184#else
185#ifdef __DSBT__
186    struct elf32_dsbt_loadaddr dlpi_addr;
187#else
188    ElfW(Addr) dlpi_addr;
189#endif
190#endif
191    const char *dlpi_name;
192    const ElfW(Phdr) *dlpi_phdr;
193    ElfW(Half) dlpi_phnum;
194
195#if 0
196    /* Note: Following members were introduced after the first
197       version of this structure was available.  Check the SIZE
198       argument passed to the dl_iterate_phdr callback to determine
199       whether or not each later member is available.  */
200
201    /* Incremented when a new object may have been added.  */
202    unsigned long long int dlpi_adds;
203    /* Incremented when an object may have been removed.  */
204    unsigned long long int dlpi_subs;
205
206    /* If there is a PT_TLS segment, its module ID as used in
207       TLS relocations, else zero.  */
208    size_t dlpi_tls_modid;
209
210    /* The address of the calling thread's instance of this module's
211       PT_TLS segment, if it has one and it has been allocated
212       in the calling thread, otherwise a null pointer.  */
213    void *dlpi_tls_data;
214#endif
215  };
216
217__BEGIN_DECLS
218
219extern int dl_iterate_phdr (int (*__callback) (struct dl_phdr_info *,
220					       size_t, void *),
221			    void *__data);
222
223
224#if 0
225/* Prototypes for the ld.so auditing interfaces.  These are not
226   defined anywhere in ld.so but instead have to be provided by the
227   auditing DSO.  */
228extern unsigned int la_version (unsigned int __version);
229extern void la_activity (uintptr_t *__cookie, unsigned int __flag);
230extern char *la_objsearch (const char *__name, uintptr_t *__cookie,
231			   unsigned int __flag);
232extern unsigned int la_objopen (struct link_map *__map, Lmid_t __lmid,
233				uintptr_t *__cookie);
234extern void la_preinit (uintptr_t *__cookie);
235extern uintptr_t la_symbind32 (Elf32_Sym *__sym, unsigned int __ndx,
236			       uintptr_t *__refcook, uintptr_t *__defcook,
237			       unsigned int *__flags, const char *__symname);
238extern uintptr_t la_symbind64 (Elf64_Sym *__sym, unsigned int __ndx,
239			       uintptr_t *__refcook, uintptr_t *__defcook,
240			       unsigned int *__flags, const char *__symname);
241extern unsigned int la_objclose (uintptr_t *__cookie);
242#endif
243
244__END_DECLS
245
246#endif
247
248#endif /* link.h */
249