diff options
Diffstat (limited to 'elf/dl-deps.c')
-rw-r--r-- | elf/dl-deps.c | 100 |
1 files changed, 95 insertions, 5 deletions
diff --git a/elf/dl-deps.c b/elf/dl-deps.c index f08f652642..04c4010b65 100644 --- a/elf/dl-deps.c +++ b/elf/dl-deps.c @@ -34,6 +34,11 @@ #define FILTERTAG (DT_NUM + DT_PROCNUM + DT_VERSIONTAGNUM \ + DT_EXTRATAGIDX (DT_FILTER)) +/* This is zero at program start to signal that the global scope map is + allocated by rtld. Later it keeps the size of the map. It might be + reset if in _dl_close if the last global object is removed. */ +size_t _dl_global_scope_alloc; + /* When loading auxiliary objects we must ignore errors. It's ok if an object is missing. */ @@ -79,11 +84,11 @@ struct list }; -void +unsigned int internal_function _dl_map_object_deps (struct link_map *map, struct link_map **preloads, unsigned int npreloads, - int trace_mode) + int trace_mode, int global_scope) { struct list known[1 + npreloads + 1]; struct list *runp, *utail, *dtail; @@ -158,7 +163,7 @@ _dl_map_object_deps (struct link_map *map, orig = runp; for (d = l->l_ld; d->d_tag != DT_NULL; ++d) - if (d->d_tag == DT_NEEDED) + if (__builtin_expect (d->d_tag, DT_NEEDED) == DT_NEEDED) { /* Map in the needed object. */ struct link_map *dep @@ -392,13 +397,98 @@ _dl_map_object_deps (struct link_map *map, map->l_searchlist.r_duplist = map->l_searchlist.r_list; else { + unsigned int cnt; + map->l_searchlist.r_duplist = malloc (nduplist * sizeof (struct link_map *)); if (map->l_searchlist.r_duplist == NULL) _dl_signal_error (ENOMEM, map->l_name, "cannot allocate symbol search list"); - for (nlist = 0, runp = known; runp; runp = runp->dup) - map->l_searchlist.r_duplist[nlist++] = runp->map; + for (cnt = 0, runp = known; runp; runp = runp->dup) + map->l_searchlist.r_duplist[cnt++] = runp->map; } + + /* Now that all this succeeded put the objects in the global scope if + this is necessary. We put the original object and all the dependencies + in the global scope. If an object is already loaded and not in the + global scope we promote it. */ + if (global_scope) + { + unsigned int cnt; + unsigned int to_add = 0; + struct link_map **new_global; + + /* Count the objects we have to put in the global scope. */ + for (cnt = 0; cnt < nlist; ++cnt) + if (map->l_searchlist.r_list[cnt]->l_global == 0) + ++to_add; + + /* The symbols of the new objects and its dependencies are to be + introduced into the global scope that will be used to resolve + references from other dynamically-loaded objects. + + The global scope is the searchlist in the main link map. We + extend this list if necessary. There is one problem though: + since this structure was allocated very early (before the libc + is loaded) the memory it uses is allocated by the malloc()-stub + in the ld.so. When we come here these functions are not used + anymore. Instead the malloc() implementation of the libc is + used. But this means the block from the main map cannot be used + in an realloc() call. Therefore we allocate a completely new + array the first time we have to add something to the locale scope. */ + + if (_dl_global_scope_alloc == 0) + { + /* This is the first dynamic object given global scope. */ + _dl_global_scope_alloc = _dl_main_searchlist->r_nlist + to_add + 8; + new_global = (struct link_map **) + malloc (_dl_global_scope_alloc * sizeof (struct link_map *)); + if (new_global == NULL) + { + _dl_global_scope_alloc = 0; + nomem: + _dl_signal_error (ENOMEM, map->l_libname->name, + "cannot extend global scope"); + return 0; + } + + /* Copy over the old entries. */ + memcpy (new_global, _dl_main_searchlist->r_list, + (_dl_main_searchlist->r_nlist * sizeof (struct link_map *))); + + _dl_main_searchlist->r_list = new_global; + } + else if (_dl_main_searchlist->r_nlist + to_add > _dl_global_scope_alloc) + { + /* We have to extend the existing array of link maps in the + main map. */ + new_global = (struct link_map **) + realloc (_dl_main_searchlist->r_list, + ((_dl_global_scope_alloc + to_add + 8) + * sizeof (struct link_map *))); + if (new_global == NULL) + goto nomem; + + _dl_global_scope_alloc += to_add + 8; + _dl_main_searchlist->r_list = new_global; + } + + /* Now add the new entries. */ + to_add = 0; + for (cnt = 0; cnt < nlist; ++cnt) + if (map->l_searchlist.r_list[cnt]->l_global == 0) + { + map->l_searchlist.r_list[cnt]->l_global = 1; + _dl_main_searchlist->r_list[_dl_main_searchlist->r_nlist + to_add] + = map->l_searchlist.r_list[cnt]; + ++to_add; + } + + /* XXX Do we have to add something to r_dupsearchlist??? --drepper */ + + return to_add; + } + + return 0; } |