about summary refs log tree commit diff
path: root/include
diff options
context:
space:
mode:
Diffstat (limited to 'include')
-rw-r--r--include/link.h220
1 files changed, 219 insertions, 1 deletions
diff --git a/include/link.h b/include/link.h
index 0999f0bbfc..38652ca46a 100644
--- a/include/link.h
+++ b/include/link.h
@@ -1 +1,219 @@
-#include <elf/link.h>
+/* Data structure for communication from the run-time dynamic linker for
+   loaded ELF shared objects.
+   Copyright (C) 1995-1999, 2000 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 of the
+   License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#ifndef	_LINK_H
+#define	_LINK_H	1
+
+#include <features.h>
+#include <elf.h>
+#include <dlfcn.h>
+#include <sys/types.h>
+
+/* We use this macro to refer to ELF types independent of the native wordsize.
+   `ElfW(TYPE)' is used in place of `Elf32_TYPE' or `Elf64_TYPE'.  */
+#define ElfW(type)	_ElfW (Elf, __ELF_NATIVE_CLASS, type)
+#define _ElfW(e,w,t)	_ElfW_1 (e, w, _##t)
+#define _ElfW_1(e,w,t)	e##w##t
+
+#include <bits/elfclass.h>		/* Defines __ELF_NATIVE_CLASS.  */
+
+/* Rendezvous structure used by the run-time dynamic linker to communicate
+   details of shared object loading to the debugger.  If the executable's
+   dynamic section has a DT_DEBUG element, the run-time linker sets that
+   element's value to the address where this structure can be found.  */
+
+struct r_debug
+  {
+    int r_version;		/* Version number for this protocol.  */
+
+    struct link_map *r_map;	/* Head of the chain of loaded objects.  */
+
+    /* This is the address of a function internal to the run-time linker,
+       that will always be called when the linker begins to map in a
+       library or unmap it, and again when the mapping change is complete.
+       The debugger can set a breakpoint at this address if it wants to
+       notice shared object mapping changes.  */
+    ElfW(Addr) r_brk;
+    enum
+      {
+	/* This state value describes the mapping change taking place when
+	   the `r_brk' address is called.  */
+	RT_CONSISTENT,		/* Mapping change is complete.  */
+	RT_ADD,			/* Beginning to add a new object.  */
+	RT_DELETE		/* Beginning to remove an object mapping.  */
+      } r_state;
+
+    ElfW(Addr) r_ldbase;	/* Base address the linker is loaded at.  */
+  };
+
+/* This is the instance of that structure used by the dynamic linker.  */
+extern struct r_debug _r_debug;
+
+/* This symbol refers to the "dynamic structure" in the `.dynamic' section
+   of whatever module refers to `_DYNAMIC'.  So, to find its own
+   `struct r_debug', a program could do:
+     for (dyn = _DYNAMIC; dyn->d_tag != DT_NULL; ++dyn)
+       if (dyn->d_tag == DT_DEBUG)
+	 r_debug = (struct r_debug *) dyn->d_un.d_ptr;
+   */
+extern ElfW(Dyn) _DYNAMIC[];
+
+
+/* Some internal data structures of the dynamic linker used in the
+   linker map.  We only provide forward declarations.  */
+struct libname_list;
+struct r_found_version;
+struct r_search_path_elem;
+
+/* Forward declaration.  */
+struct link_map;
+
+/* Structure to describe a single list of scope elements.  The lookup
+   functions get passed an array of pointers to such structures.  */
+struct r_scope_elem
+{
+  /* Array of maps for the scope.  */
+  struct link_map **r_list;
+  /* Number of entries in the scope.  */
+  unsigned int r_nlist;
+
+  /* Array of maps which also includes duplicates.  */
+  struct link_map **r_duplist;
+  /* Number of elements in this list.  */
+  unsigned int r_nduplist;
+};
+
+
+/* Structure describing a loaded shared object.  The `l_next' and `l_prev'
+   members form a chain of all the shared objects loaded at startup.
+
+   These data structures exist in space used by the run-time dynamic linker;
+   modifying them may have disastrous results.
+
+   This data structure might change in future, if necessary.  User-level
+   programs must avoid defining objects of this type.  */
+
+struct link_map
+  {
+    /* These first few members are part of the protocol with the debugger.
+       This is the same format used in SVR4.  */
+
+    ElfW(Addr) l_addr;		/* Base address shared object is loaded at.  */
+    char *l_name;		/* Absolute file name object was found in.  */
+    ElfW(Dyn) *l_ld;		/* Dynamic section of the shared object.  */
+    struct link_map *l_next, *l_prev; /* Chain of loaded objects.  */
+
+    /* All following members are internal to the dynamic linker.
+       They may change without notice.  */
+
+    struct libname_list *l_libname;
+    /* Indexed pointers to dynamic section.
+       [0,DT_NUM) are indexed by the processor-independent tags.
+       [DT_NUM,DT_NUM+DT_THISPROCNUM) are indexed by the tag minus DT_LOPROC.
+       [DT_NUM+DT_THISPROCNUM,DT_NUM+DT_THISPROCNUM+DT_EXTRANUM) are indexed
+       by DT_EXTRATAGIDX(tagvalue) and
+       [DT_NUM+DT_THISPROCNUM+DT_VERSIONTAGNUM,
+        DT_NUM+DT_THISPROCNUM+DT_VERSIONTAGNUM+DT_EXTRANUM)
+       are indexed by DT_EXTRATAGIDX(tagvalue) (see <elf.h>).  */
+
+    ElfW(Dyn) *l_info[DT_NUM + DT_THISPROCNUM + DT_VERSIONTAGNUM
+		     + DT_EXTRANUM];
+    const ElfW(Phdr) *l_phdr;	/* Pointer to program header table in core.  */
+    ElfW(Addr) l_entry;		/* Entry point location.  */
+    ElfW(Half) l_phnum;		/* Number of program header entries.  */
+    ElfW(Half) l_ldnum;	/* Number of dynamic segment entries.  */
+
+    /* Array of DT_NEEDED dependencies and their dependencies, in
+       dependency order for symbol lookup (with and without
+       duplicates).  There is no entry before the dependencies have
+       been loaded.  */
+    struct r_scope_elem l_searchlist;
+
+    /* We need a special searchlist to process objects marked with
+       DT_SYMBOLIC.  */
+    struct r_scope_elem l_symbolic_searchlist;
+
+    /* Dependent object that first caused this object to be loaded.  */
+    struct link_map *l_loader;
+
+    /* Symbol hash table.  */
+    Elf_Symndx l_nbuckets;
+    const Elf_Symndx *l_buckets, *l_chain;
+
+    unsigned int l_opencount;	/* Reference count for dlopen/dlclose.  */
+    enum			/* Where this object came from.  */
+      {
+	lt_executable,		/* The main executable program.  */
+	lt_library,		/* Library needed by main executable.  */
+	lt_loaded		/* Extra run-time loaded shared object.  */
+      } l_type:2;
+    unsigned int l_relocated:1;	/* Nonzero if object's relocations done.  */
+    unsigned int l_init_called:1; /* Nonzero if DT_INIT function called.  */
+    unsigned int l_global:1;	/* Nonzero if object in _dl_global_scope.  */
+    unsigned int l_reserved:2;	/* Reserved for internal use.  */
+    unsigned int l_phdr_allocated:1; /* Nonzero if the data structure pointed
+					to by `l_phdr' is allocated.  */
+
+    /* Array with version names.  */
+    unsigned int l_nversions;
+    struct r_found_version *l_versions;
+
+    /* Collected information about own RPATH directories.  */
+    struct r_search_path_elem **l_rpath_dirs;
+
+    /* Collected results of relocation while profiling.  */
+    ElfW(Addr) *l_reloc_result;
+
+    /* Pointer to the version information if available.  */
+    ElfW(Versym) *l_versyms;
+
+    /* String specifying the path where this object was found.  */
+    const char *l_origin;
+
+    /* Start and finish of memory map for this object.  l_map_start
+       need not be the same as l_addr.  */
+    ElfW(Addr) l_map_start, l_map_end;
+
+    /* This is an array defining the lookup scope for this link map.
+     There are at most three different scope lists.  */
+    struct r_scope_elem *l_scope[4];
+
+    /* A similar array, this time only with the local scope.  This is
+       used occasionally.  */
+    struct r_scope_elem *l_local_scope[2];
+
+    /* This information is kept to check for sure whether a shared
+       object is the same as one already loaded.  */
+    dev_t l_dev;
+    ino_t l_ino;
+
+    /* Collected information about own RUNPATH directories.  */
+    struct r_search_path_elem **l_runpath_dirs;
+
+    /* List of object in order of the init and fini calls.  */
+    struct link_map **l_initfini;
+
+    /* List of the dependencies introduced through symbol binding.  */
+    unsigned int l_reldepsmax;
+    unsigned int l_reldepsact;
+    struct link_map **l_reldeps;
+  };
+
+#endif /* link.h */