diff options
Diffstat (limited to 'newlib/libc/sys/linux/dl/dl-libc.c')
| -rw-r--r-- | newlib/libc/sys/linux/dl/dl-libc.c | 156 |
1 files changed, 156 insertions, 0 deletions
diff --git a/newlib/libc/sys/linux/dl/dl-libc.c b/newlib/libc/sys/linux/dl/dl-libc.c new file mode 100644 index 000000000..c83448df7 --- /dev/null +++ b/newlib/libc/sys/linux/dl/dl-libc.c @@ -0,0 +1,156 @@ +/* Handle loading and unloading shared objects for internal libc purposes. + Copyright (C) 1999, 2000, 2001 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Zack Weinberg <zack@rabi.columbia.edu>, 1999. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 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 + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include <dlfcn.h> +#include <stdlib.h> +#include <ldsodefs.h> + +/* The purpose of this file is to provide wrappers around the dynamic + linker error mechanism (similar to dlopen() et al in libdl) which + are usable from within libc. Generally we want to throw away the + string that dlerror() would return and just pass back a null pointer + for errors. This also lets the rest of libc not know about the error + handling mechanism. + + Much of this code came from gconv_dl.c with slight modifications. */ + +static int +internal_function +dlerror_run (void (*operate) (void *), void *args) +{ + const char *objname; + const char *last_errstring = NULL; + int result; + + (void) _dl_catch_error (&objname, &last_errstring, operate, args); + + result = last_errstring != NULL; + if (result && last_errstring != _dl_out_of_memory) + free ((char *) last_errstring); + + return result; +} + +/* These functions are called by dlerror_run... */ + +struct do_dlopen_args +{ + /* Argument to do_dlopen. */ + const char *name; + + /* Return from do_dlopen. */ + struct link_map *map; +}; + +struct do_dlsym_args +{ + /* Arguments to do_dlsym. */ + struct link_map *map; + const char *name; + + /* Return values of do_dlsym. */ + lookup_t loadbase; + const ElfW(Sym) *ref; +}; + +static void +do_dlopen (void *ptr) +{ + struct do_dlopen_args *args = (struct do_dlopen_args *) ptr; + /* Open and relocate the shared object. */ + args->map = _dl_open (args->name, RTLD_LAZY, NULL); +} + +static void +do_dlsym (void *ptr) +{ + struct do_dlsym_args *args = (struct do_dlsym_args *) ptr; + args->ref = NULL; + args->loadbase = _dl_lookup_symbol (args->name, args->map, &args->ref, + args->map->l_local_scope, 0, 1); +} + +static void +do_dlclose (void *ptr) +{ + _dl_close ((struct link_map *) ptr); +} + +/* ... and these functions call dlerror_run. */ + +void * +__libc_dlopen (const char *__name) +{ + struct do_dlopen_args args; + args.name = __name; + + return (dlerror_run (do_dlopen, &args) ? NULL : (void *) args.map); +} + +void * +__libc_dlsym (void *__map, const char *__name) +{ + struct do_dlsym_args args; + args.map = __map; + args.name = __name; + + return (dlerror_run (do_dlsym, &args) ? NULL + : (void *) (DL_SYMBOL_ADDRESS (args.loadbase, args.ref))); +} + +int +__libc_dlclose (void *__map) +{ + return dlerror_run (do_dlclose, __map); +} + + +static void +free_mem (void) +{ + struct link_map *l; + struct r_search_path_elem *d; + + /* Remove all search directories. */ + d = _dl_all_dirs; + while (d != _dl_init_all_dirs) + { + struct r_search_path_elem *old = d; + d = d->next; + free (old); + } + + /* Remove all additional names added to the objects. */ + for (l = _dl_loaded; l != NULL; l = l->l_next) + { + struct libname_list *lnp = l->l_libname->next; + + l->l_libname->next = NULL; + + while (lnp != NULL) + { + struct libname_list *old = lnp; + lnp = lnp->next; + if (! old->dont_free) + free (old); + } + } +} +text_set_element (__libc_subfreeres, free_mem); |