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authorUlrich Drepper <drepper@redhat.com>1998-03-24 00:39:45 +0000
committerUlrich Drepper <drepper@redhat.com>1998-03-24 00:39:45 +0000
commita853022cc32c8286018294e08cd4990ffcaf1d2b (patch)
treea81d55830b93a8c1cc58eaf0da8c7779984e1fa3 /elf/link.h
parentb3a86ae1a749caf2d885a8faba45b9977762ca9e (diff)
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Update.
1998-03-24  Ulrich Drepper  <drepper@cygnus.com>

	* elf/ldsodesf.h: New file.
	* elf/Makefile (distribute): Add ldsodefs.h.
	* elf/link.h: Separate internal information in exter header.
	* elf/rtld.c: Include elf/ldsodefs.h not link.h.
	* elf/dl-minimal.c: Likewise.
	* sysdeps/generic/dl-sysdep.c: Likewise.
	* elf/sprof.c: Likewise.
	* elf/dlsym.c: Likewise.
	* elf/dlvsym.c: Likewise.
	* elf/dlerror.c: Likewise.
	* elf/dladdr.c: Likewise.
	* elf/dlclose.c: Likewise.
	* elf/dlopen.c: Likewise.
	* elf/dl-addr.c: Likewise.
	* elf/dl-close.c: Likewise.
	* elf/dl-debug.c: Likewise.
	* elf/dl-deps.c: Likewise.
	* elf/dl-error.c: Likewise.
	* elf/dl-fini.c: Likewise.
	* elf/dl-init.c: Likewise.
	* elf/dl-load.c: Likewise.
	* elf/dl-lookup.c: Likewise.
	* elf/dl-object.c: Likewise.
	* elf/dl-open.c: Likewise.
	* elf/dl-profile.c: Likewise.
	* elf/dl-reloc.c: Likewise.
	* elf/dl-runtime.c: Likewise.
	* elf/dl-support.c: Likewise.
	* elf/dl-symbol.c: Likewise.
	* elf/dl-version.c: Likewise.
	* sysdeps/generic/dl-cache.c: Likewise.
	* sysdeps/generic/libc-start.c: Likewise.
	* iconv/gconv_dl.c: Likewise.
	* nss/nsswitch.c: Likewise.
Diffstat (limited to 'elf/link.h')
-rw-r--r--elf/link.h368
1 files changed, 12 insertions, 356 deletions
diff --git a/elf/link.h b/elf/link.h
index 9b0f898b11..30efa0ed25 100644
--- a/elf/link.h
+++ b/elf/link.h
@@ -1,4 +1,5 @@
-/* Run-time dynamic linker data structures for loaded ELF shared objects.
+/* Data structure for communication from the run-time dynamic linker for
+   loaded ELF shared objects.
    Copyright (C) 1995, 1996, 1997, 1998 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
@@ -21,20 +22,12 @@
 #define	_LINK_H	1
 
 #include <features.h>
-
-#define __need_size_t
-#define __need_NULL
-#include <stddef.h>
-
 #include <elf.h>
 #include <dlfcn.h>
 
-__BEGIN_DECLS
-
 /* 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(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
 
@@ -78,56 +71,24 @@ extern struct r_debug _r_debug;
      for (dyn = _DYNAMIC; dyn->d_tag != DT_NULL)
        if (dyn->d_tag == DT_DEBUG) r_debug = (struct r_debug) dyn->d_un.d_ptr;
    */
-
 extern ElfW(Dyn) _DYNAMIC[];
 
-/* For the version handling we need an array with only names and their
-   hash values.  */
-struct r_found_version
-  {
-    const char *name;
-    ElfW(Word) hash;
-
-    int hidden;
-    const char *filename;
-  };
-
-/* We want to cache information about the searches for shared objects.  */
-
-enum r_dir_status { unknown, nonexisting, existing };
-
-struct r_search_path_elem
-  {
-    const char *dirname;
-
-    size_t dirnamelen;
-    enum r_dir_status dirstatus;
-
-    size_t machdirnamelen;
-    enum r_dir_status machdirstatus;
-
-    /* Strings saying where the definition came from.  */
-    const char *what;
-    const char *where;
 
-    /* This link is only used in the `all_dirs' member of `r_search_path'.  */
-    struct r_search_path_elem *next;
-  };
-
-
-/* A data structure for a simple single linked list of strings.  */
-struct libname_list
-  {
-    const char *name;		/* Name requested (before search).  */
-    struct libname_list *next;	/* Link to next name for this object.  */
-  };
+/* 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;
 
 
 /* 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.  */
+   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
   {
@@ -142,7 +103,7 @@ struct link_map
     /* All following members are internal to the dynamic linker.
        They may change without notice.  */
 
-    struct libname_list  *l_libname;
+    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_PROCNUM) are indexed by the tag minus DT_LOPROC.
@@ -202,309 +163,4 @@ struct link_map
     ElfW(Half) *l_versyms;
   };
 
-
-/* Test whether given NAME matches any of the names of the given object.  */
-static __inline int
-__attribute__ ((unused))
-_dl_name_match_p (const char *__name, struct link_map *__map)
-{
-  int __found = strcmp (__name, __map->l_name) == 0;
-  struct libname_list *__runp = __map->l_libname;
-
-  while (! __found && __runp != NULL)
-    if (strcmp (__name, __runp->name) == 0)
-      __found = 1;
-    else
-      __runp = __runp->next;
-
-  return __found;
-}
-
-/* Function used as argument for `_dl_receive_error' function.  The
-   arguments are the error code, error string, and the objname the
-   error occurred in.  */
-typedef void (*receiver_fct) (int, const char *, const char *);
-
-/* Internal functions of the run-time dynamic linker.
-   These can be accessed if you link again the dynamic linker
-   as a shared library, as in `-lld' or `/lib/ld.so' explicitly;
-   but are not normally of interest to user programs.
-
-   The `-ldl' library functions in <dlfcn.h> provide a simple
-   user interface to run-time dynamic linking.  */
-
-
-/* Parameters passed to the dynamic linker.  */
-extern char **_dl_argv;
-
-/* Cached value of `getpagesize ()'.  */
-extern size_t _dl_pagesize;
-
-/* File descriptor referring to the zero-fill device.  */
-extern int _dl_zerofd;
-
-/* Name of the shared object to be profiled (if any).  */
-extern const char *_dl_profile;
-/* Map of shared object to be profiled.  */
-extern struct link_map *_dl_profile_map;
-
-/* If nonzero the appropriate debug information is printed.  */
-extern int _dl_debug_libs;
-extern int _dl_debug_impcalls;
-extern int _dl_debug_bindings;
-extern int _dl_debug_symbols;
-extern int _dl_debug_versions;
-extern int _dl_debug_reloc;
-extern int _dl_debug_files;
-
-/* File deccriptor to write debug messages to.  */
-extern int _dl_debug_fd;
-
-/* OS-dependent function to open the zero-fill device.  */
-extern int _dl_sysdep_open_zero_fill (void); /* dl-sysdep.c */
-
-/* OS-dependent function to write a message on the specified
-   descriptor FD.  All arguments are `const char *'; args until a null
-   pointer are concatenated to form the message to print.  */
-extern void _dl_sysdep_output (int fd, const char *string, ...);
-
-/* OS-dependent function to write a debug message on the specified
-   descriptor for this.  All arguments are `const char *'; args until
-   a null pointer are concatenated to form the message to print.  If
-   NEW_LINE is nonzero it is assumed that the message starts on a new
-   line.*/
-extern void _dl_debug_message (int new_line, const char *string, ...);
-
-/* OS-dependent function to write a message on the standard output.
-   All arguments are `const char *'; args until a null pointer
-   are concatenated to form the message to print.  */
-#define _dl_sysdep_message(string, args...) \
-  _dl_sysdep_output (STDOUT_FILENO, string, ##args)
-
-/* OS-dependent function to write a message on the standard error.
-   All arguments are `const char *'; args until a null pointer
-   are concatenated to form the message to print.  */
-#define _dl_sysdep_error(string, args...) \
-  _dl_sysdep_output (STDERR_FILENO, string, ##args)
-
-/* OS-dependent function to give a fatal error message and exit
-   when the dynamic linker fails before the program is fully linked.
-   All arguments are `const char *'; args until a null pointer
-   are concatenated to form the message to print.  */
-#define _dl_sysdep_fatal(string, args...) \
-  do									      \
-    {									      \
-      _dl_sysdep_output (STDERR_FILENO, string, ##args);		      \
-      _exit (127);							      \
-    }									      \
-  while (1)
-
-/* Nonzero if the program should be "secure" (i.e. it's setuid or somesuch).
-   This tells the dynamic linker to ignore environment variables.  */
-extern int _dl_secure;
-
-/* This function is called by all the internal dynamic linker functions
-   when they encounter an error.  ERRCODE is either an `errno' code or
-   zero; OBJECT is the name of the problematical shared object, or null if
-   it is a general problem; ERRSTRING is a string describing the specific
-   problem.  */
-extern void _dl_signal_error (int errcode,
-			      const char *object,
-			      const char *errstring);
-
-/* Call OPERATE, catching errors from `dl_signal_error'.  If there is no
-   error, *ERRSTRING is set to null.  If there is an error, *ERRSTRING is
-   set to a string constructed from the strings passed to _dl_signal_error,
-   and the error code passed is the return value.  ERRSTRING if nonzero
-   points to a malloc'ed string which the caller has to free after use.
-   ARGS is passed as argument to OPERATE.  */
-extern int _dl_catch_error (char **errstring,
-			    void (*operate) (void *),
-			    void *args);
-
-/* Call OPERATE, receiving errors from `dl_signal_error'.  Unlike
-   `_dl_catch_error' the operation is resumed after the OPERATE
-   function returns.
-   ARGS is passed as argument to OPERATE.  */
-extern void _dl_receive_error (receiver_fct fct, void (*operate) (void *),
-			       void *args);
-
-
-/* Helper function for <dlfcn.h> functions.  Runs the OPERATE function via
-   _dl_catch_error.  Returns zero for success, nonzero for failure; and
-   arranges for `dlerror' to return the error details.
-   ARGS is passed as argument to OPERATE.  */
-extern int _dlerror_run (void (*operate) (void *), void *args);
-
-
-/* Open the shared object NAME and map in its segments.
-   LOADER's DT_RPATH is used in searching for NAME.
-   If the object is already opened, returns its existing map.
-   For preloaded shared objects PRELOADED is set to a non-zero
-   value to allow additional security checks.  */
-extern struct link_map *_dl_map_object (struct link_map *loader,
-					const char *name, int preloaded,
-					int type, int trace_mode);
-
-/* Call _dl_map_object on the dependencies of MAP, and set up
-   MAP->l_searchlist.  PRELOADS points to a vector of NPRELOADS previously
-   loaded objects that will be inserted into MAP->l_searchlist after MAP
-   but before its dependencies.  */
-extern void _dl_map_object_deps (struct link_map *map,
-				 struct link_map **preloads,
-				 unsigned int npreloads, int trace_mode);
-
-/* Cache the locations of MAP's hash table.  */
-extern void _dl_setup_hash (struct link_map *map);
-
-
-/* Open the shared object NAME, relocate it, and run its initializer if it
-   hasn't already been run.  MODE is as for `dlopen' (see <dlfcn.h>).  If
-   the object is already opened, returns its existing map.  */
-extern struct link_map *_dl_open (const char *name, int mode);
-
-/* Close an object previously opened by _dl_open.  */
-extern void _dl_close (struct link_map *map);
-
-
-/* Search loaded objects' symbol tables for a definition of the symbol
-   referred to by UNDEF.  *SYM is the symbol table entry containing the
-   reference; it is replaced with the defining symbol, and the base load
-   address of the defining object is returned.  SYMBOL_SCOPE is a
-   null-terminated list of object scopes to search; each object's
-   l_searchlist (i.e. the segment of the dependency tree starting at that
-   object) is searched in turn.  REFERENCE_NAME should name the object
-   containing the reference; it is used in error messages.
-   RELOC_TYPE is a machine-dependent reloc type, which is passed to
-   the `elf_machine_lookup_*_p' macros in dl-machine.h to affect which
-   symbols can be chosen.  */
-extern ElfW(Addr) _dl_lookup_symbol (const char *undef,
-				     const ElfW(Sym) **sym,
-				     struct link_map *symbol_scope[],
-				     const char *reference_name,
-				     int reloc_type);
-
-/* Lookup versioned symbol.  */
-extern ElfW(Addr) _dl_lookup_versioned_symbol (const char *undef,
-					       const ElfW(Sym) **sym,
-					       struct link_map *symbol_scope[],
-					       const char *reference_name,
-					       const struct r_found_version *version,
-					       int reloc_type);
-
-/* For handling RTLD_NEXT we must be able to skip shared objects.  */
-extern ElfW(Addr) _dl_lookup_symbol_skip (const char *undef,
-					  const ElfW(Sym) **sym,
-					  struct link_map *symbol_scope[],
-					  const char *reference_name,
-					  struct link_map *skip_this);
-
-/* For handling RTLD_NEXT with versioned symbols we must be able to
-   skip shared objects.  */
-extern ElfW(Addr) _dl_lookup_versioned_symbol_skip (const char *undef,
-						    const ElfW(Sym) **sym,
-						    struct link_map *symbol_scope[],
-						    const char *reference_name,
-						    const struct r_found_version *version,
-						    struct link_map *skip_this);
-
-/* Locate shared object containing the given address.  */
-extern int _dl_addr (const void *address, Dl_info *info);
-
-/* Look up symbol NAME in MAP's scope and return its run-time address.  */
-extern ElfW(Addr) _dl_symbol_value (struct link_map *map, const char *name);
-
-
-/* Structure describing the dynamic linker itself.  */
-extern struct link_map _dl_rtld_map;
-
-/* The list of objects currently loaded is the third element of the
-   `_dl_default_scope' array, and the fourth element is always null.
-   This leaves two slots before it that are used when resolving
-   DT_SYMBOLIC objects' references one after it for normal references
-   (see below).  */
-#define _dl_loaded	(_dl_default_scope[2])
-extern struct link_map *_dl_default_scope[5];
-
-/* Null-terminated list of objects in the dynamic `global scope'.  The
-   list starts at [2]; i.e. &_dl_global_scope[2] is the argument
-   passed to _dl_lookup_symbol to search the global scope.  To search
-   a specific object and its dependencies in preference to the global
-   scope, fill in the [1] slot and pass its address; for two specific
-   object scopes, fill [0] and [1].  The list is double-terminated; to
-   search the global scope and then a specific object and its
-   dependencies, set *_dl_global_scope_end.  This variable initially
-   points to _dl_default_scope, and _dl_loaded is always kept in [2]
-   of this list.  A new list is malloc'd when new objects are loaded
-   with RTLD_GLOBAL.  */
-extern struct link_map **_dl_global_scope, **_dl_global_scope_end;
-extern size_t _dl_global_scope_alloc; /* Number of slots malloc'd.  */
-
-/* Hack _dl_global_scope[0] and [1] as necessary, and return a pointer into
-   _dl_global_scope that should be passed to _dl_lookup_symbol for symbol
-   references made in the object MAP's relocations.  */
-extern struct link_map **_dl_object_relocation_scope (struct link_map *map);
-
-
-/* Allocate a `struct link_map' for a new object being loaded,
-   and enter it into the _dl_loaded list.  */
-extern struct link_map *_dl_new_object (char *realname, const char *libname,
-					int type);
-
-/* Relocate the given object (if it hasn't already been).
-   SCOPE is passed to _dl_lookup_symbol in symbol lookups.
-   If LAZY is nonzero, don't relocate its PLT.  */
-extern void _dl_relocate_object (struct link_map *map,
-				 struct link_map *scope[],
-				 int lazy);
-
-/* Check the version dependencies of all objects available through
-   MAP.  If VERBOSE print some more diagnostics.  */
-extern int _dl_check_all_versions (struct link_map *map, int verbose);
-
-/* Check the version dependencies for MAP.  If VERBOSE print some more
-   diagnostics.  */
-extern int _dl_check_map_versions (struct link_map *map, int verbose);
-
-/* Return the address of the next initializer function for MAP or one of
-   its dependencies that has not yet been run.  When there are no more
-   initializers to be run, this returns zero.  The functions are returned
-   in the order they should be called.  */
-extern ElfW(Addr) _dl_init_next (struct link_map *map);
-
-/* Call the finalizer functions of all shared objects whose
-   initializer functions have completed.  */
-extern void _dl_fini (void);
-
-/* The dynamic linker calls this function before and having changing
-   any shared object mappings.  The `r_state' member of `struct r_debug'
-   says what change is taking place.  This function's address is
-   the value of the `r_brk' member.  */
-extern void _dl_debug_state (void);
-
-/* Initialize `struct r_debug' if it has not already been done.  The
-   argument is the run-time load address of the dynamic linker, to be put
-   in the `r_ldbase' member.  Returns the address of the structure.  */
-extern struct r_debug *_dl_debug_initialize (ElfW(Addr) ldbase);
-
-/* Initialize the basic data structure for the search paths.  */
-extern void _dl_init_paths (const char *library_path);
-
-/* Gather the information needed to install the profiling tables and start
-   the timers.  */
-extern void _dl_start_profile (struct link_map *map, const char *output_dir);
-
-/* The actual functions used to keep book on the calls.  */
-extern void _dl_mcount (ElfW(Addr) frompc, ElfW(Addr) selfpc);
-
-
-/* Show the members of the auxiliary array passed up from the kernel.  */
-extern void _dl_show_auxv (void);
-
-/* Return all environment variables starting with `LD_', one after the
-   other.  */
-extern char *_dl_next_ld_env_entry (char ***position);
-
-__END_DECLS
-
 #endif /* link.h */