ldso/libdl/libdl.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * Program to load an ELF binary on a linux system, and run it
   4  * after resolving ELF shared library symbols
   5  *
   6  * Copyright (C) 2000-2006 by Erik Andersen <andersen@uclibc.org>
   7  * Copyright (c) 1994-2000 Eric Youngdale, Peter MacDonald,
   8  *                              David Engel, Hongjiu Lu and Mitch D'Souza
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. The name of the above contributors may not be
  16  *    used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  */
  31
  32
  33 #include <ldso.h>
  34 #include <stdio.h>
  35
  36
  37 #ifdef SHARED
  38
  39 /* When libdl is loaded as a shared library, we need to load in
  40  * and use a pile of symbols from ldso... */
  41
  42 extern char *_dl_find_hash(const char *, struct dyn_elf *, struct elf_resolve *, int);
  43 extern struct elf_resolve * _dl_load_shared_library(int, struct dyn_elf **,
  44         struct elf_resolve *, char *, int);
  45 extern int _dl_fixup(struct dyn_elf *rpnt, int lazy);
  46 extern void _dl_protect_relro(struct elf_resolve * tpnt);
  47 extern int _dl_errno;
  48 extern struct dyn_elf *_dl_symbol_tables;
  49 extern struct dyn_elf *_dl_handles;
  50 extern struct elf_resolve *_dl_loaded_modules;
  51 extern struct r_debug *_dl_debug_addr;
  52 extern unsigned long _dl_error_number;
  53 extern void *(*_dl_malloc_function)(size_t);
  54 extern void _dl_run_init_array(struct elf_resolve *);
  55 extern void _dl_run_fini_array(struct elf_resolve *);
  56 #ifdef __LDSO_CACHE_SUPPORT__
  57 int _dl_map_cache(void);
  58 int _dl_unmap_cache(void);
  59 #endif
  60 #ifdef __mips__
  61 extern void _dl_perform_mips_global_got_relocations(struct elf_resolve *tpnt, int lazy);
  62 #endif
  63 #ifdef __SUPPORT_LD_DEBUG__
  64 extern char *_dl_debug;
  65 #endif
  66
  67
  68 #else /* SHARED */
  69
  70 /* When libdl is linked as a static library, we need to replace all
  71  * the symbols that otherwise would have been loaded in from ldso... */
  72
  73 #ifdef __SUPPORT_LD_DEBUG__
  74 char *_dl_debug  = 0;
  75 #endif
  76 const char *_dl_progname       = "";        /* Program name */
  77 char *_dl_library_path         = 0;         /* Where we look for libraries */
  78 char *_dl_ldsopath             = 0;         /* Location of the shared lib loader */
  79 int _dl_errno                  = 0;         /* We can't use the real errno in ldso */
  80 size_t _dl_pagesize            = PAGE_SIZE; /* Store the page size for use later */
  81 /* This global variable is also to communicate with debuggers such as gdb. */
  82 struct r_debug *_dl_debug_addr = NULL;
  83 #define _dl_malloc malloc
  84 #include "../ldso/dl-debug.c"
  85 #include LDSO_ELFINTERP
  86 #include "../ldso/dl-hash.c"
  87 #define _dl_trace_loaded_objects    0
  88 #include "../ldso/dl-elf.c"
  89 #endif /* SHARED */
  90
  91 #ifdef __SUPPORT_LD_DEBUG__
  92 # define _dl_if_debug_print(fmt, args...) \
  93         do { \
  94         if (_dl_debug) \
  95                 fprintf(stderr, "%s():%i: " fmt, __FUNCTION__, __LINE__, ## args); \
  96         } while (0)
  97 #else
  98 # define _dl_if_debug_print(fmt, args...)
  99 #endif
 100
 101 static int do_dlclose(void *, int need_fini);
 102
 103
 104 static const char *dl_error_names[] = {
 105         "",
 106         "File not found",
 107         "Unable to open /dev/zero",
 108         "Not an ELF file",
 109 #if defined (__i386__)
 110         "Not i386 binary",
 111 #elif defined (__sparc__)
 112         "Not sparc binary",
 113 #elif defined (__mc68000__)
 114         "Not m68k binary",
 115 #else
 116         "Unrecognized binary type",
 117 #endif
 118         "Not an ELF shared library",
 119         "Unable to mmap file",
 120         "No dynamic section",
 121 #ifdef ELF_USES_RELOCA
 122         "Unable to process REL relocs",
 123 #else
 124         "Unable to process RELA relocs",
 125 #endif
 126         "Bad handle",
 127         "Unable to resolve symbol"
 128 };
 129
 130 void dl_cleanup(void) __attribute__ ((destructor));
 131 void dl_cleanup(void)
 132 {
 133         struct dyn_elf *d;
 134         for (d = _dl_handles; d; d = d->next_handle) {
 135                 do_dlclose(d, 1);
 136         }
 137 }
 138
 139 void *dlopen(const char *libname, int flag)
 140 {
 141         struct elf_resolve *tpnt, *tfrom;
 142         struct dyn_elf *dyn_chain, *rpnt = NULL, *dyn_ptr, *relro_ptr, *handle;
 143         ElfW(Addr) from;
 144         struct elf_resolve *tpnt1;
 145         void (*dl_brk) (void);
 146         int now_flag;
 147         struct init_fini_list *tmp, *runp, *runp2, *dep_list;
 148         unsigned int nlist, i;
 149         struct elf_resolve **init_fini_list;
 150
 151         /* A bit of sanity checking... */
 152         if (!(flag & (RTLD_LAZY|RTLD_NOW))) {
 153                 _dl_error_number = LD_BAD_HANDLE;
 154                 return NULL;
 155         }
 156
 157         from = (ElfW(Addr)) __builtin_return_address(0);
 158
 159         /* Cover the trivial case first */
 160         if (!libname)
 161                 return _dl_symbol_tables;
 162
 163         _dl_map_cache();
 164
 165         /*
 166          * Try and locate the module we were called from - we
 167          * need this so that we get the correct RPATH/RUNPATH.  Note that
 168          * this is the current behavior under Solaris, but the
 169          * ABI+ specifies that we should only use the RPATH from
 170          * the application.  Thus this may go away at some time
 171          * in the future.
 172          */
 173         {
 174                 struct dyn_elf *dpnt;
 175                 tfrom = NULL;
 176                 for (dpnt = _dl_symbol_tables; dpnt; dpnt = dpnt->next) {
 177                         tpnt = dpnt->dyn;
 178                         if (DL_ADDR_IN_LOADADDR(from, tpnt, tfrom))
 179                                 tfrom = tpnt;
 180                 }
 181         }
 182         for(rpnt = _dl_symbol_tables; rpnt && rpnt->next; rpnt=rpnt->next);
 183
 184         relro_ptr = rpnt;
 185         now_flag = (flag & RTLD_NOW) ? RTLD_NOW : 0;
 186         if (getenv("LD_BIND_NOW"))
 187                 now_flag = RTLD_NOW;
 188
 189         /* Try to load the specified library */
 190         _dl_if_debug_print("Trying to dlopen '%s', RTLD_GLOBAL:%d RTLD_NOW:%d\n",
 191                         (char*)libname, (flag & RTLD_GLOBAL ? 1:0), (now_flag & RTLD_NOW ? 1:0));
 192         tpnt = _dl_load_shared_library(0, &rpnt, tfrom, (char*)libname, 0);
 193
 194         if (tpnt == NULL) {
 195                 _dl_unmap_cache();
 196                 return NULL;
 197         }
 198         dyn_chain = (struct dyn_elf *) malloc(sizeof(struct dyn_elf));
 199         _dl_memset(dyn_chain, 0, sizeof(struct dyn_elf));
 200         dyn_chain->dyn = tpnt;
 201         tpnt->rtld_flags |= (flag & RTLD_GLOBAL);
 202
 203         dyn_chain->next_handle = _dl_handles;
 204         _dl_handles = dyn_ptr = dyn_chain;
 205
 206         if (tpnt->usage_count > 1) {
 207                 _dl_if_debug_print("Lib: %s already opened\n", libname);
 208                 /* see if there is a handle from a earlier dlopen */
 209                 for (handle = _dl_handles->next_handle; handle; handle = handle->next_handle) {
 210                         if (handle->dyn == tpnt) {
 211                                 dyn_chain->init_fini.init_fini = handle->init_fini.init_fini;
 212                                 dyn_chain->init_fini.nlist = handle->init_fini.nlist;
 213                                 for(i=0; i < dyn_chain->init_fini.nlist; i++)
 214                                         dyn_chain->init_fini.init_fini[i]->rtld_flags |= (flag & RTLD_GLOBAL);
 215                                 dyn_chain->next = handle->next;
 216                                 break;
 217                         }
 218                 }
 219                 return dyn_chain;
 220         } else {
 221                 tpnt->init_flag |= DL_OPENED;
 222         }
 223
 224         _dl_if_debug_print("Looking for needed libraries\n");
 225         nlist = 0;
 226         runp = alloca(sizeof(*runp));
 227         runp->tpnt = tpnt;
 228         runp->next = NULL;
 229         dep_list = runp2 = runp;
 230         for (; runp; runp = runp->next)
 231         {
 232                 ElfW(Dyn) *dpnt;
 233                 char *lpntstr;
 234
 235                 nlist++;
 236                 runp->tpnt->init_fini = NULL; /* clear any previous dependcies */
 237                 for (dpnt = (ElfW(Dyn) *) runp->tpnt->dynamic_addr; dpnt->d_tag; dpnt++) {
 238                         if (dpnt->d_tag == DT_NEEDED) {
 239                                 lpntstr = (char*) (runp->tpnt->dynamic_info[DT_STRTAB] +
 240                                                 dpnt->d_un.d_val);
 241                                 _dl_if_debug_print("Trying to load '%s', needed by '%s'\n",
 242                                                 lpntstr, runp->tpnt->libname);
 243                                 tpnt1 = _dl_load_shared_library(0, &rpnt, runp->tpnt, lpntstr, 0);
 244                                 if (!tpnt1)
 245                                         goto oops;
 246
 247                                 tpnt1->rtld_flags |= (flag & RTLD_GLOBAL);
 248
 249                                 /* This list is for dlsym() and relocation */
 250                                 dyn_ptr->next = (struct dyn_elf *) malloc(sizeof(struct dyn_elf));
 251                                 _dl_memset (dyn_ptr->next, 0, sizeof (struct dyn_elf));
 252                                 dyn_ptr = dyn_ptr->next;
 253                                 dyn_ptr->dyn = tpnt1;
 254                                 /* Used to record RTLD_LOCAL scope */
 255                                 tmp = alloca(sizeof(struct init_fini_list));
 256                                 tmp->tpnt = tpnt1;
 257                                 tmp->next = runp->tpnt->init_fini;
 258                                 runp->tpnt->init_fini = tmp;
 259
 260                                 for (tmp=dep_list; tmp; tmp = tmp->next) {
 261                                         if (tpnt1 == tmp->tpnt) { /* if match => cirular dependency, drop it */
 262                                                 _dl_if_debug_print("Circular dependency, skipping '%s',\n",
 263                                                                    tmp->tpnt->libname);
 264                                                 tpnt1->usage_count--;
 265                                                 break;
 266                                         }
 267                                 }
 268                                 if (!tmp) { /* Don't add if circular dependency detected */
 269                                         runp2->next = alloca(sizeof(*runp));
 270                                         runp2 = runp2->next;
 271                                         runp2->tpnt = tpnt1;
 272                                         runp2->next = NULL;
 273                                 }
 274                         }
 275                 }
 276         }
 277         init_fini_list = malloc(nlist * sizeof(struct elf_resolve *));
 278         dyn_chain->init_fini.init_fini = init_fini_list;
 279         dyn_chain->init_fini.nlist = nlist;
 280         i = 0;
 281         for (runp2 = dep_list; runp2; runp2 = runp2->next) {
 282                 init_fini_list[i++] = runp2->tpnt;
 283                 for(runp = runp2->tpnt->init_fini; runp; runp = runp->next){
 284                         if (!(runp->tpnt->rtld_flags & RTLD_GLOBAL)) {
 285                                 tmp = malloc(sizeof(struct init_fini_list));
 286                                 tmp->tpnt = runp->tpnt;
 287                                 tmp->next = runp2->tpnt->rtld_local;
 288                                 runp2->tpnt->rtld_local = tmp;
 289                         }
 290                 }
 291
 292         }
 293         /* Sort the INIT/FINI list in dependency order. */
 294         for (runp2 = dep_list; runp2; runp2 = runp2->next) {
 295                 unsigned int j, k;
 296                 for (j = 0; init_fini_list[j] != runp2->tpnt; ++j)
 297                         /* Empty */;
 298                 for (k = j + 1; k < nlist; ++k) {
 299                         struct init_fini_list *ele = init_fini_list[k]->init_fini;
 300
 301                         for (; ele; ele = ele->next) {
 302                                 if (ele->tpnt == runp2->tpnt) {
 303                                         struct elf_resolve *here = init_fini_list[k];
 304                                         _dl_if_debug_print("Move %s from pos %d to %d in INIT/FINI list.\n", here->libname, k, j);
 305                                         for (i = (k - j); i; --i)
 306                                                 init_fini_list[i+j] = init_fini_list[i+j-1];
 307                                         init_fini_list[j] = here;
 308                                         ++j;
 309                                         break;
 310                                 }
 311                         }
 312                 }
 313         }
 314 #ifdef __SUPPORT_LD_DEBUG__
 315         if(_dl_debug) {
 316                 fprintf(stderr, "\nINIT/FINI order and dependencies:\n");
 317                 for (i=0;i < nlist;i++) {
 318                         fprintf(stderr, "lib: %s has deps:\n", init_fini_list[i]->libname);
 319                         runp = init_fini_list[i]->init_fini;
 320                         for (; runp; runp = runp->next)
 321                                 printf(" %s ", runp->tpnt->libname);
 322                         printf("\n");
 323                 }
 324         }
 325 #endif
 326
 327         _dl_if_debug_print("Beginning dlopen relocation fixups\n");
 328         /*
 329          * OK, now all of the kids are tucked into bed in their proper addresses.
 330          * Now we go through and look for REL and RELA records that indicate fixups
 331          * to the GOT tables.  We need to do this in reverse order so that COPY
 332          * directives work correctly */
 333 #ifdef __mips__
 334         /*
 335          * Relocation of the GOT entries for MIPS have to be done
 336          * after all the libraries have been loaded.
 337          */
 338         _dl_perform_mips_global_got_relocations(tpnt, !now_flag);
 339 #endif
 340
 341         if (_dl_fixup(dyn_chain, now_flag))
 342                 goto oops;
 343
 344         if (relro_ptr) {
 345                 for (rpnt = relro_ptr->next; rpnt; rpnt = rpnt->next) {
 346                         if (rpnt->dyn->relro_size)
 347                                 _dl_protect_relro(rpnt->dyn);
 348                 }
 349         }
 350         /* TODO:  Should we set the protections of all pages back to R/O now ? */
 351
 352
 353         /* Notify the debugger we have added some objects. */
 354         if (_dl_debug_addr) {
 355                 dl_brk = (void (*)(void)) _dl_debug_addr->r_brk;
 356                 if (dl_brk != NULL) {
 357                         _dl_debug_addr->r_state = RT_ADD;
 358                         (*dl_brk) ();
 359
 360                         _dl_debug_addr->r_state = RT_CONSISTENT;
 361                         (*dl_brk) ();
 362                 }
 363         }
 364
 365 #ifdef SHARED
 366         /* Run the ctors and setup the dtors */
 367         for (i = nlist; i; --i) {
 368                 tpnt = init_fini_list[i-1];
 369                 if (tpnt->init_flag & INIT_FUNCS_CALLED)
 370                         continue;
 371                 tpnt->init_flag |= INIT_FUNCS_CALLED;
 372
 373                 if (tpnt->dynamic_info[DT_INIT]) {
 374                         void (*dl_elf_func) (void);
 375                         dl_elf_func = (void (*)(void)) DL_RELOC_ADDR(tpnt->loadaddr, tpnt->dynamic_info[DT_INIT]);
 376                         if (dl_elf_func) {
 377                                 _dl_if_debug_print("running ctors for library %s at '%p'\n",
 378                                                 tpnt->libname, dl_elf_func);
 379                                 DL_CALL_FUNC_AT_ADDR (dl_elf_func, tpnt->loadaddr, (void(*)(void)));
 380                         }
 381                 }
 382
 383                 _dl_run_init_array(tpnt);
 384         }
 385 #endif /* SHARED */
 386
 387         _dl_unmap_cache();
 388         return (void *) dyn_chain;
 389
 390 oops:
 391         /* Something went wrong.  Clean up and return NULL. */
 392         _dl_unmap_cache();
 393         do_dlclose(dyn_chain, 0);
 394         return NULL;
 395 }
 396
 397 void *dlsym(void *vhandle, const char *name)
 398 {
 399         struct elf_resolve *tpnt, *tfrom;
 400         struct dyn_elf *handle;
 401         ElfW(Addr) from;
 402         struct dyn_elf *rpnt;
 403         void *ret;
 404
 405         handle = (struct dyn_elf *) vhandle;
 406
 407         /* First of all verify that we have a real handle
 408            of some kind.  Return NULL if not a valid handle. */
 409
 410         if (handle == NULL)
 411                 handle = _dl_symbol_tables;
 412         else if (handle != RTLD_NEXT && handle != _dl_symbol_tables) {
 413                 for (rpnt = _dl_handles; rpnt; rpnt = rpnt->next_handle)
 414                         if (rpnt == handle)
 415                                 break;
 416                 if (!rpnt) {
 417                         _dl_error_number = LD_BAD_HANDLE;
 418                         return NULL;
 419                 }
 420         } else if (handle == RTLD_NEXT) {
 421                 /*
 422                  * Try and locate the module we were called from - we
 423                  * need this so that we know where to start searching
 424                  * from.  We never pass RTLD_NEXT down into the actual
 425                  * dynamic loader itself, as it doesn't know
 426                  * how to properly treat it.
 427                  */
 428                 from = (ElfW(Addr)) __builtin_return_address(0);
 429
 430                 tfrom = NULL;
 431                 for (rpnt = _dl_symbol_tables; rpnt; rpnt = rpnt->next) {
 432                         tpnt = rpnt->dyn;
 433                         if (DL_ADDR_IN_LOADADDR(from, tpnt, tfrom)) {
 434                                 tfrom = tpnt;
 435                                 handle = rpnt->next;
 436                         }
 437                 }
 438         }
 439         tpnt = NULL;
 440         if (handle == _dl_symbol_tables)
 441            tpnt = handle->dyn; /* Only search RTLD_GLOBAL objs if global object */
 442         ret = _dl_find_hash((char*)name, handle, tpnt, 0);
 443
 444         /*
 445          * Nothing found.
 446          */
 447         if (!ret)
 448                 _dl_error_number = LD_NO_SYMBOL;
 449         return ret;
 450 }
 451
 452 #if 0
 453 void *dlvsym(void *vhandle, const char *name, const char *version)
 454 {
 455         return dlsym(vhandle, name);
 456 }
 457 #endif
 458
 459 static int do_dlclose(void *vhandle, int need_fini)
 460 {
 461         struct dyn_elf *rpnt, *rpnt1, *rpnt1_tmp;
 462         struct init_fini_list *runp, *tmp;
 463         ElfW(Phdr) *ppnt;
 464         struct elf_resolve *tpnt, *run_tpnt;
 465         int (*dl_elf_fini) (void);
 466         void (*dl_brk) (void);
 467         struct dyn_elf *handle;
 468         unsigned int end;
 469         unsigned int i, j;
 470
 471         handle = (struct dyn_elf *) vhandle;
 472         if (handle == _dl_symbol_tables)
 473                 return 0;
 474         rpnt1 = NULL;
 475         for (rpnt = _dl_handles; rpnt; rpnt = rpnt->next_handle) {
 476                 if (rpnt == handle)
 477                         break;
 478                 rpnt1 = rpnt;
 479         }
 480
 481         if (!rpnt) {
 482                 _dl_error_number = LD_BAD_HANDLE;
 483                 return 1;
 484         }
 485         if (rpnt1)
 486                 rpnt1->next_handle = rpnt->next_handle;
 487         else
 488                 _dl_handles = rpnt->next_handle;
 489         _dl_if_debug_print("%s: usage count: %d\n",
 490                         handle->dyn->libname, handle->dyn->usage_count);
 491         if (handle->dyn->usage_count != 1) {
 492                 handle->dyn->usage_count--;
 493                 free(handle);
 494                 return 0;
 495         }
 496         /* OK, this is a valid handle - now close out the file */
 497         for (j = 0; j < handle->init_fini.nlist; ++j) {
 498                 tpnt = handle->init_fini.init_fini[j];
 499                 if (--tpnt->usage_count == 0) {
 500                         if ((tpnt->dynamic_info[DT_FINI]
 501                              || tpnt->dynamic_info[DT_FINI_ARRAY])
 502                             && need_fini &&
 503                             !(tpnt->init_flag & FINI_FUNCS_CALLED)) {
 504                                 tpnt->init_flag |= FINI_FUNCS_CALLED;
 505 #ifdef SHARED
 506                                 _dl_run_fini_array(tpnt);
 507 #endif
 508
 509                                 if (tpnt->dynamic_info[DT_FINI]) {
 510                                         dl_elf_fini = (int (*)(void)) DL_RELOC_ADDR(tpnt->loadaddr, tpnt->dynamic_info[DT_FINI]);
 511                                         _dl_if_debug_print("running dtors for library %s at '%p'\n",
 512                                                         tpnt->libname, dl_elf_fini);
 513                                         DL_CALL_FUNC_AT_ADDR (dl_elf_fini, tpnt->loadaddr, (int (*)(void)));
 514                                 }
 515                         }
 516
 517                         _dl_if_debug_print("unmapping: %s\n", tpnt->libname);
 518                         end = 0;
 519                         for (i = 0, ppnt = tpnt->ppnt;
 520                                         i < tpnt->n_phent; ppnt++, i++) {
 521                                 if (ppnt->p_type != PT_LOAD)
 522                                         continue;
 523                                 if (end < ppnt->p_vaddr + ppnt->p_memsz)
 524                                         end = ppnt->p_vaddr + ppnt->p_memsz;
 525                         }
 526                         _dl_munmap((void*)tpnt->loadaddr, end);
 527                         /* Free elements in RTLD_LOCAL scope list */
 528                         for (runp = tpnt->rtld_local; runp; runp = tmp) {
 529                                 tmp = runp->next;
 530                                 free(runp);
 531                         }
 532
 533                         /* Next, remove tpnt from the loaded_module list */
 534                         if (_dl_loaded_modules == tpnt) {
 535                                 _dl_loaded_modules = tpnt->next;
 536                                 if (_dl_loaded_modules)
 537                                         _dl_loaded_modules->prev = 0;
 538                         } else
 539                                 for (run_tpnt = _dl_loaded_modules; run_tpnt; run_tpnt = run_tpnt->next)
 540                                         if (run_tpnt->next == tpnt) {
 541                                                 _dl_if_debug_print("removing loaded_modules: %s\n", tpnt->libname);
 542                                                 run_tpnt->next = run_tpnt->next->next;
 543                                                 if (run_tpnt->next)
 544                                                         run_tpnt->next->prev = run_tpnt;
 545                                                 break;
 546                                         }
 547
 548                         /* Next, remove tpnt from the global symbol table list */
 549                         if (_dl_symbol_tables) {
 550                                 if (_dl_symbol_tables->dyn == tpnt) {
 551                                         _dl_symbol_tables = _dl_symbol_tables->next;
 552                                         if (_dl_symbol_tables)
 553                                                 _dl_symbol_tables->prev = 0;
 554                                 } else
 555                                         for (rpnt1 = _dl_symbol_tables; rpnt1->next; rpnt1 = rpnt1->next) {
 556                                                 if (rpnt1->next->dyn == tpnt) {
 557                                                         _dl_if_debug_print("removing symbol_tables: %s\n", tpnt->libname);
 558                                                         rpnt1_tmp = rpnt1->next->next;
 559                                                         free(rpnt1->next);
 560                                                         rpnt1->next = rpnt1_tmp;
 561                                                         if (rpnt1->next)
 562                                                                 rpnt1->next->prev = rpnt1;
 563                                                         break;
 564                                                 }
 565                                         }
 566                         }
 567                         free(tpnt->libname);
 568                         free(tpnt);
 569                 }
 570         }
 571         free(handle->init_fini.init_fini);
 572         free(handle);
 573
 574
 575         if (_dl_debug_addr) {
 576                 dl_brk = (void (*)(void)) _dl_debug_addr->r_brk;
 577                 if (dl_brk != NULL) {
 578                         _dl_debug_addr->r_state = RT_DELETE;
 579                         (*dl_brk) ();
 580
 581                         _dl_debug_addr->r_state = RT_CONSISTENT;
 582                         (*dl_brk) ();
 583                 }
 584         }
 585
 586         return 0;
 587 }
 588
 589 int dlclose(void *vhandle)
 590 {
 591         return do_dlclose(vhandle, 1);
 592 }
 593
 594 char *dlerror(void)
 595 {
 596         const char *retval;
 597
 598         if (!_dl_error_number)
 599                 return NULL;
 600         retval = dl_error_names[_dl_error_number];
 601         _dl_error_number = 0;
 602         return (char *)retval;
 603 }
 604
 605 /*
 606  * Dump information to stderr about the current loaded modules
 607  */
 608 #ifdef __USE_GNU
 609 static char *type[] = { "Lib", "Exe", "Int", "Mod" };
 610
 611 int dlinfo(void)
 612 {
 613         struct elf_resolve *tpnt;
 614         struct dyn_elf *rpnt, *hpnt;
 615
 616         fprintf(stderr, "List of loaded modules\n");
 617         /* First start with a complete list of all of the loaded files. */
 618         for (tpnt = _dl_loaded_modules; tpnt; tpnt = tpnt->next) {
 619                 fprintf(stderr, "\t%p %p %p %s %d %s\n",
 620                         DL_LOADADDR_BASE(tpnt->loadaddr), tpnt, tpnt->symbol_scope,
 621                         type[tpnt->libtype],
 622                         tpnt->usage_count, tpnt->libname);
 623         }
 624
 625         /* Next dump the module list for the application itself */
 626         fprintf(stderr, "\nModules for application (%p):\n", _dl_symbol_tables);
 627         for (rpnt = _dl_symbol_tables; rpnt; rpnt = rpnt->next)
 628                 fprintf(stderr, "\t%p %s\n", rpnt->dyn, rpnt->dyn->libname);
 629
 630         for (hpnt = _dl_handles; hpnt; hpnt = hpnt->next_handle) {
 631                 fprintf(stderr, "Modules for handle %p\n", hpnt);
 632                 for (rpnt = hpnt; rpnt; rpnt = rpnt->next)
 633                         fprintf(stderr, "\t%p %s\n", rpnt->dyn, rpnt->dyn->libname);
 634         }
 635         return 0;
 636 }
 637
 638 int dladdr(const void *__address, Dl_info * __info)
 639 {
 640         struct elf_resolve *pelf;
 641         struct elf_resolve *rpnt;
 642
 643         _dl_map_cache();
 644
 645         /*
 646          * Try and locate the module address is in
 647          */
 648         pelf = NULL;
 649
 650         _dl_if_debug_print("__address: %p  __info: %p\n", __address, __info);
 651
 652         for (rpnt = _dl_loaded_modules; rpnt; rpnt = rpnt->next) {
 653                 struct elf_resolve *tpnt;
 654
 655                 tpnt = rpnt;
 656
 657                 _dl_if_debug_print("Module \"%s\" at %p\n",
 658                                    tpnt->libname, DL_LOADADDR_BASE(tpnt->loadaddr));
 659
 660                 if (DL_ADDR_IN_LOADADDR((ElfW(Addr)) __address, tpnt, pelf))
 661                         pelf = tpnt;
 662         }
 663
 664         if (!pelf) {
 665                 return 0;
 666         }
 667
 668         /*
 669          * Try and locate the symbol of address
 670          */
 671
 672         {
 673                 char *strtab;
 674                 ElfW(Sym) *symtab;
 675                 unsigned int hn, si, sn, sf;
 676                 ElfW(Addr) sa;
 677
 678                 sa = 0;
 679                 symtab = (ElfW(Sym) *) (pelf->dynamic_info[DT_SYMTAB]);
 680                 strtab = (char *) (pelf->dynamic_info[DT_STRTAB]);
 681
 682                 sf = sn = 0;
 683                 for (hn = 0; hn < pelf->nbucket; hn++) {
 684                         for (si = pelf->elf_buckets[hn]; si; si = pelf->chains[si]) {
 685                                 ElfW(Addr) symbol_addr;
 686
 687                                 symbol_addr = (ElfW(Addr)) DL_RELOC_ADDR(pelf->loadaddr, symtab[si].st_value);
 688                                 if (symbol_addr <= (ElfW(Addr))__address && (!sf || sa < symbol_addr)) {
 689                                         sa = symbol_addr;
 690                                         sn = si;
 691                                         sf = 1;
 692                                 }
 693
 694                                 _dl_if_debug_print("Symbol \"%s\" at %p\n",
 695                                                    strtab + symtab[si].st_name, symbol_addr);
 696                         }
 697                 }
 698
 699                 if (sf) {
 700                         __info->dli_fname = pelf->libname;
 701                         __info->dli_fbase = (void *) DL_LOADADDR_BASE(pelf->loadaddr);
 702                         __info->dli_sname = strtab + symtab[sn].st_name;
 703                         __info->dli_saddr = (void *)sa;
 704                 }
 705                 return 1;
 706         }
 707 }
 708 #endif