diff options
Diffstat (limited to 'elf')
| -rw-r--r-- | elf/dl-close.c | 23 | ||||
| -rw-r--r-- | elf/dl-deps.c | 11 | ||||
| -rw-r--r-- | elf/dl-open.c | 25 | ||||
| -rw-r--r-- | elf/dl-version.c | 9 | ||||
| -rw-r--r-- | elf/dlclose.c | 4 |
5 files changed, 53 insertions, 19 deletions
diff --git a/elf/dl-close.c b/elf/dl-close.c index 7e851cd0af..fa9e92cb9f 100644 --- a/elf/dl-close.c +++ b/elf/dl-close.c @@ -1,5 +1,5 @@ -/* _dl_close -- Close a shared object opened by `_dl_open'. - Copyright (C) 1996 Free Software Foundation, Inc. +/* Close a shared object opened by `_dl_open'. + Copyright (C) 1996, 1997 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 @@ -23,8 +23,14 @@ #include <string.h> #include <sys/types.h> #include <sys/mman.h> +#include <libc-lock.h> +/* During the program run we must not modify the global data of + loaded shared object simultanously in two threads. Therefore we + protect `dlopen' and `dlclose' in dlclose.c. */ +__libc_lock_define (extern, _dl_load_lock) + #define LOSE(s) _dl_signal_error (0, map->l_name, s) void @@ -36,10 +42,16 @@ _dl_close (struct link_map *map) if (map->l_opencount == 0) LOSE ("shared object not open"); + /* Acquire the lock. */ + __libc_lock_lock (_dl_load_lock); + /* Decrement the reference count. */ if (--map->l_opencount > 0 || map->l_type != lt_loaded) - /* There are still references to this object. Do nothing more. */ - return; + { + /* There are still references to this object. Do nothing more. */ + __libc_lock_unlock (_dl_load_lock); + return; + } /* Notify the debugger we are about to remove some loaded objects. */ _r_debug.r_state = RT_DELETE; @@ -114,4 +126,7 @@ _dl_close (struct link_map *map) /* Notify the debugger those objects are finalized and gone. */ _r_debug.r_state = RT_CONSISTENT; _dl_debug_state (); + + /* Release the lock. */ + __libc_lock_unlock (_dl_load_lock); } diff --git a/elf/dl-deps.c b/elf/dl-deps.c index 38db7677b0..27de231dff 100644 --- a/elf/dl-deps.c +++ b/elf/dl-deps.c @@ -84,7 +84,7 @@ _dl_map_object_deps (struct link_map *map, int trace_mode) { struct list known[1 + npreloads + 1]; - struct list *runp, *head, *utail, *dtail; + struct list *runp, *utail, *dtail; unsigned int nlist, nduplist, i; inline void preload (struct link_map *map) @@ -116,9 +116,6 @@ _dl_map_object_deps (struct link_map *map, known[nlist - 1].unique = NULL; known[nlist - 1].dup = NULL; - /* Pointer to the first member of the unique and duplicate list. */ - head = known; - /* Pointer to last unique object. */ utail = &known[nlist - 1]; /* Pointer to last loaded object. */ @@ -300,7 +297,7 @@ _dl_map_object_deps (struct link_map *map, situation is really not that frequent. So we don't use a double-linked list but instead search for the preceding element. */ - late = head; + late = known; while (late->unique != orig) late = late->unique; late->unique = newp; @@ -361,7 +358,7 @@ _dl_map_object_deps (struct link_map *map, "cannot allocate symbol search list"); map->l_nsearchlist = nlist; - for (nlist = 0, runp = head; runp; runp = runp->unique) + for (nlist = 0, runp = known; runp; runp = runp->unique) { map->l_searchlist[nlist++] = runp->map; @@ -380,7 +377,7 @@ _dl_map_object_deps (struct link_map *map, _dl_signal_error (ENOMEM, map->l_name, "cannot allocate symbol search list"); - for (nlist = 0, runp = head; runp; runp = runp->dup) + for (nlist = 0, runp = known; runp; runp = runp->dup) map->l_dupsearchlist[nlist++] = runp->map; } } diff --git a/elf/dl-open.c b/elf/dl-open.c index 529806cc36..113e472165 100644 --- a/elf/dl-open.c +++ b/elf/dl-open.c @@ -21,6 +21,7 @@ #include <dlfcn.h> #include <stdlib.h> #include <errno.h> +#include <libc-lock.h> extern ElfW(Addr) _dl_sysdep_start (void **start_argptr, @@ -38,6 +39,17 @@ extern char **__environ; size_t _dl_global_scope_alloc; + +/* During the program run we must not modify the global data of + loaded shared object simultanously in two threads. Therefore we + protect `_dl_open' and `_dl_close' in dl-close.c. + + This must be a recursive lock since the initializer function of + the loaded object might as well require a call to this function. + At this time it is not anymore a problem to modify the tables. */ +__libc_lock_define_initialized_recursive (, _dl_load_lock) + + struct link_map * _dl_open (const char *file, int mode) { @@ -45,11 +57,17 @@ _dl_open (const char *file, int mode) ElfW(Addr) init; struct r_debug *r; + /* Make sure we are alone. */ + __libc_lock_lock (_dl_load_lock); + /* Load the named object. */ new = _dl_map_object (NULL, file, lt_loaded, 0); if (new->l_searchlist) - /* It was already open. */ - return new; + { + /* It was already open. */ + __libc_lock_unlock (_dl_load_lock); + return new; + } /* Load that object's dependencies. */ _dl_map_object_deps (new, NULL, 0, 0); @@ -152,5 +170,8 @@ _dl_open (const char *file, int mode) has loaded a dynamic object now has competition. */ __libc_multiple_libcs = 1; + /* Release the lock. */ + __libc_lock_unlock (_dl_load_lock); + return new; } diff --git a/elf/dl-version.c b/elf/dl-version.c index b5515c86e0..0f98dd057c 100644 --- a/elf/dl-version.c +++ b/elf/dl-version.c @@ -46,7 +46,7 @@ extern char **_dl_argv; \ cp = result = alloca (len); \ for (cnt = 0; cnt < sizeof (all) / sizeof (all[0]); ++cnt) \ - cp = stpcpy (cp, all[cnt]); \ + cp = __stpcpy (cp, all[cnt]); \ \ result; \ }) @@ -55,11 +55,12 @@ extern char **_dl_argv; static inline struct link_map * find_needed (const char *name, struct link_map *map) { + struct link_map *tmap; unsigned int n; - for (n = 0; n < _dl_loaded->l_nsearchlist; ++n) - if (_dl_name_match_p (name, _dl_loaded->l_searchlist[n])) - return _dl_loaded->l_searchlist[n]; + for (tmap = _dl_loaded; tmap != NULL; tmap = tmap->l_next) + if (_dl_name_match_p (name, tmap)) + return tmap; /* The required object is not in the global scope, look to see if it is a dependency of the current object. */ diff --git a/elf/dlclose.c b/elf/dlclose.c index d96ffc9cc1..a2ec750baf 100644 --- a/elf/dlclose.c +++ b/elf/dlclose.c @@ -1,5 +1,5 @@ -/* dlclose -- Close a handle opened by `dlopen'. - Copyright (C) 1995, 1996 Free Software Foundation, Inc. +/* Close a handle opened by `dlopen'. + Copyright (C) 1995, 1996, 1997 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 |