boehm-gc/dyn_load.c

   1 /*
   2  * Copyright (c) 1991-1994 by Xerox Corporation.  All rights reserved.
   3  * Copyright (c) 1997 by Silicon Graphics.  All rights reserved.
   4  *
   5  * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
   6  * OR IMPLIED.  ANY USE IS AT YOUR OWN RISK.
   7  *
   8  * Permission is hereby granted to use or copy this program
   9  * for any purpose,  provided the above notices are retained on all copies.
  10  * Permission to modify the code and to distribute modified code is granted,
  11  * provided the above notices are retained, and a notice that the code was
  12  * modified is included with the above copyright notice.
  13  *
  14  * Original author: Bill Janssen
  15  * Heavily modified by Hans Boehm and others
  16  */
  17
  18 /*
  19  * This is incredibly OS specific code for tracking down data sections in
  20  * dynamic libraries.  There appears to be no way of doing this quickly
  21  * without groveling through undocumented data structures.  We would argue
  22  * that this is a bug in the design of the dlopen interface.  THIS CODE
  23  * MAY BREAK IN FUTURE OS RELEASES.  If this matters to you, don't hesitate
  24  * to let your vendor know ...
  25  *
  26  * None of this is safe with dlclose and incremental collection.
  27  * But then not much of anything is safe in the presence of dlclose.
  28  */
  29 #if defined(__linux__) && !defined(_GNU_SOURCE)
  30     /* Can't test LINUX, since this must be define before other includes */
  31 #   define _GNU_SOURCE
  32 #endif
  33 #if !defined(MACOS) && !defined(_WIN32_WCE)
  34 #  include <sys/types.h>
  35 #endif
  36 #include "private/gc_priv.h"
  37
  38 /* BTL: avoid circular redefinition of dlopen if GC_SOLARIS_THREADS defined */
  39 # if (defined(GC_PTHREADS) || defined(GC_SOLARIS_THREADS)) \
  40       && defined(dlopen) && !defined(GC_USE_LD_WRAP)
  41     /* To support threads in Solaris, gc.h interposes on dlopen by       */
  42     /* defining "dlopen" to be "GC_dlopen", which is implemented below.  */
  43     /* However, both GC_FirstDLOpenedLinkMap() and GC_dlopen() use the   */
  44     /* real system dlopen() in their implementation. We first remove     */
  45     /* gc.h's dlopen definition and restore it later, after GC_dlopen(). */
  46 #   undef dlopen
  47 #   define GC_must_restore_redefined_dlopen
  48 # else
  49 #   undef GC_must_restore_redefined_dlopen
  50 # endif
  51
  52 #if (defined(DYNAMIC_LOADING) || defined(MSWIN32) || defined(MSWINCE)) \
  53     && !defined(PCR)
  54 #if !defined(SUNOS4) && !defined(SUNOS5DL) && !defined(IRIX5) && \
  55     !defined(MSWIN32) && !defined(MSWINCE) && \
  56     !(defined(ALPHA) && defined(OSF1)) && \
  57     !defined(HPUX) && !(defined(LINUX) && defined(__ELF__)) && \
  58     !defined(RS6000) && !defined(SCO_ELF) && \
  59     !(defined(FREEBSD) && defined(__ELF__)) && \
  60     !(defined(NETBSD) && defined(__ELF__)) && !defined(HURD)
  61  --> We only know how to find data segments of dynamic libraries for the
  62  --> above.  Additional SVR4 variants might not be too
  63  --> hard to add.
  64 #endif
  65
  66 #include <stdio.h>
  67 #ifdef SUNOS5DL
  68 #   include <sys/elf.h>
  69 #   include <dlfcn.h>
  70 #   include <link.h>
  71 #endif
  72 #ifdef SUNOS4
  73 #   include <dlfcn.h>
  74 #   include <link.h>
  75 #   include <a.out.h>
  76   /* struct link_map field overrides */
  77 #   define l_next       lm_next
  78 #   define l_addr       lm_addr
  79 #   define l_name       lm_name
  80 #endif
  81
  82
  83 #if defined(SUNOS5DL) && !defined(USE_PROC_FOR_LIBRARIES)
  84
  85 #ifdef LINT
  86     Elf32_Dyn _DYNAMIC;
  87 #endif
  88
  89 static struct link_map *
  90 GC_FirstDLOpenedLinkMap()
  91 {
  92     extern Elf32_Dyn _DYNAMIC;
  93     Elf32_Dyn *dp;
  94     struct r_debug *r;
  95     static struct link_map * cachedResult = 0;
  96     static Elf32_Dyn *dynStructureAddr = 0;
  97                         /* BTL: added to avoid Solaris 5.3 ld.so _DYNAMIC bug */
  98
  99 #   ifdef SUNOS53_SHARED_LIB
 100         /* BTL: Avoid the Solaris 5.3 bug that _DYNAMIC isn't being set */
 101         /* up properly in dynamically linked .so's. This means we have  */
 102         /* to use its value in the set of original object files loaded  */
 103         /* at program startup.                                          */
 104         if( dynStructureAddr == 0 ) {
 105           void* startupSyms = dlopen(0, RTLD_LAZY);
 106           dynStructureAddr = (Elf32_Dyn*)dlsym(startupSyms, "_DYNAMIC");
 107                 }
 108 #   else
 109         dynStructureAddr = &_DYNAMIC;
 110 #   endif
 111
 112     if( dynStructureAddr == 0) {
 113         return(0);
 114     }
 115     if( cachedResult == 0 ) {
 116         int tag;
 117         for( dp = ((Elf32_Dyn *)(&_DYNAMIC)); (tag = dp->d_tag) != 0; dp++ ) {
 118             if( tag == DT_DEBUG ) {
 119                 struct link_map *lm
 120                         = ((struct r_debug *)(dp->d_un.d_ptr))->r_map;
 121                 if( lm != 0 ) cachedResult = lm->l_next; /* might be NIL */
 122                 break;
 123             }
 124         }
 125     }
 126     return cachedResult;
 127 }
 128
 129 #endif /* SUNOS5DL ... */
 130
 131 /* BTL: added to fix circular dlopen definition if GC_SOLARIS_THREADS defined */
 132 # if defined(GC_must_restore_redefined_dlopen)
 133 #   define dlopen GC_dlopen
 134 # endif
 135
 136 #if defined(SUNOS4) && !defined(USE_PROC_FOR_LIBRARIES)
 137
 138 #ifdef LINT
 139     struct link_dynamic _DYNAMIC;
 140 #endif
 141
 142 static struct link_map *
 143 GC_FirstDLOpenedLinkMap()
 144 {
 145     extern struct link_dynamic _DYNAMIC;
 146
 147     if( &_DYNAMIC == 0) {
 148         return(0);
 149     }
 150     return(_DYNAMIC.ld_un.ld_1->ld_loaded);
 151 }
 152
 153 /* Return the address of the ld.so allocated common symbol      */
 154 /* with the least address, or 0 if none.                        */
 155 static ptr_t GC_first_common()
 156 {
 157     ptr_t result = 0;
 158     extern struct link_dynamic _DYNAMIC;
 159     struct rtc_symb * curr_symbol;
 160
 161     if( &_DYNAMIC == 0) {
 162         return(0);
 163     }
 164     curr_symbol = _DYNAMIC.ldd -> ldd_cp;
 165     for (; curr_symbol != 0; curr_symbol = curr_symbol -> rtc_next) {
 166         if (result == 0
 167             || (ptr_t)(curr_symbol -> rtc_sp -> n_value) < result) {
 168             result = (ptr_t)(curr_symbol -> rtc_sp -> n_value);
 169         }
 170     }
 171     return(result);
 172 }
 173
 174 #endif  /* SUNOS4 ... */
 175
 176 # if defined(SUNOS4) || defined(SUNOS5DL)
 177 /* Add dynamic library data sections to the root set.           */
 178 # if !defined(PCR) && !defined(GC_SOLARIS_THREADS) && defined(THREADS)
 179 #   ifndef SRC_M3
 180         --> fix mutual exclusion with dlopen
 181 #   endif  /* We assume M3 programs don't call dlopen for now */
 182 # endif
 183
 184 # ifndef USE_PROC_FOR_LIBRARIES
 185 void GC_register_dynamic_libraries()
 186 {
 187   struct link_map *lm = GC_FirstDLOpenedLinkMap();
 188
 189
 190   for (lm = GC_FirstDLOpenedLinkMap();
 191        lm != (struct link_map *) 0;  lm = lm->l_next)
 192     {
 193 #     ifdef SUNOS4
 194         struct exec *e;
 195
 196         e = (struct exec *) lm->lm_addr;
 197         GC_add_roots_inner(
 198                     ((char *) (N_DATOFF(*e) + lm->lm_addr)),
 199                     ((char *) (N_BSSADDR(*e) + e->a_bss + lm->lm_addr)),
 200                     TRUE);
 201 #     endif
 202 #     ifdef SUNOS5DL
 203         Elf32_Ehdr * e;
 204         Elf32_Phdr * p;
 205         unsigned long offset;
 206         char * start;
 207         register int i;
 208
 209         e = (Elf32_Ehdr *) lm->l_addr;
 210         p = ((Elf32_Phdr *)(((char *)(e)) + e->e_phoff));
 211         offset = ((unsigned long)(lm->l_addr));
 212         for( i = 0; i < (int)(e->e_phnum); ((i++),(p++)) ) {
 213           switch( p->p_type ) {
 214             case PT_LOAD:
 215               {
 216                 if( !(p->p_flags & PF_W) ) break;
 217                 start = ((char *)(p->p_vaddr)) + offset;
 218                 GC_add_roots_inner(
 219                   start,
 220                   start + p->p_memsz,
 221                   TRUE
 222                 );
 223               }
 224               break;
 225             default:
 226               break;
 227           }
 228         }
 229 #     endif
 230     }
 231 #   ifdef SUNOS4
 232       {
 233         static ptr_t common_start = 0;
 234         ptr_t common_end;
 235         extern ptr_t GC_find_limit();
 236
 237         if (common_start == 0) common_start = GC_first_common();
 238         if (common_start != 0) {
 239             common_end = GC_find_limit(common_start, TRUE);
 240             GC_add_roots_inner((char *)common_start, (char *)common_end, TRUE);
 241         }
 242       }
 243 #   endif
 244 }
 245
 246 # endif /* !USE_PROC ... */
 247 # endif /* SUNOS */
 248
 249 #if defined(LINUX) && defined(__ELF__) || defined(SCO_ELF) || \
 250     (defined(FREEBSD) && defined(__ELF__)) || \
 251     (defined(NETBSD) && defined(__ELF__)) || defined(HURD)
 252
 253
 254 #ifdef USE_PROC_FOR_LIBRARIES
 255
 256 #include <string.h>
 257
 258 #include <sys/stat.h>
 259 #include <fcntl.h>
 260 #include <unistd.h>
 261
 262 #define MAPS_BUF_SIZE (32*1024)
 263
 264 extern ssize_t GC_repeat_read(int fd, char *buf, size_t count);
 265         /* Repeatedly read until buffer is filled, or EOF is encountered */
 266         /* Defined in os_dep.c.                                          */
 267
 268 static char *parse_map_entry(char *buf_ptr, word *start, word *end,
 269                              char *prot_buf, unsigned int *maj_dev);
 270
 271 void GC_register_dynamic_libraries()
 272 {
 273     int f;
 274     int result;
 275     char prot_buf[5];
 276     int maps_size;
 277     char maps_temp[32768];
 278     char *maps_buf;
 279     char *buf_ptr;
 280     int count;
 281     word start, end;
 282     unsigned int maj_dev, min_dev;
 283     word least_ha, greatest_ha;
 284     unsigned i;
 285     word datastart = (word)(DATASTART);
 286
 287     /* Read /proc/self/maps     */
 288         /* Note that we may not allocate, and thus can't use stdio.     */
 289         f = open("/proc/self/maps", O_RDONLY);
 290         if (-1 == f) ABORT("Couldn't open /proc/self/maps");
 291         /* stat() doesn't work for /proc/self/maps, so we have to
 292            read it to find out how large it is... */
 293         maps_size = 0;
 294         do {
 295             result = GC_repeat_read(f, maps_temp, sizeof(maps_temp));
 296             if (result <= 0) ABORT("Couldn't read /proc/self/maps");
 297             maps_size += result;
 298         } while (result == sizeof(maps_temp));
 299
 300         if (maps_size > sizeof(maps_temp)) {
 301             /* If larger than our buffer, close and re-read it. */
 302             close(f);
 303             f = open("/proc/self/maps", O_RDONLY);
 304             if (-1 == f) ABORT("Couldn't open /proc/self/maps");
 305             maps_buf = alloca(maps_size);
 306             if (NULL == maps_buf) ABORT("/proc/self/maps alloca failed");
 307             result = GC_repeat_read(f, maps_buf, maps_size);
 308             if (result <= 0) ABORT("Couldn't read /proc/self/maps");
 309         } else {
 310             /* Otherwise use the fixed size buffer */
 311             maps_buf = maps_temp;
 312         }
 313
 314         close(f);
 315         maps_buf[result] = '\0';
 316         buf_ptr = maps_buf;
 317     /* Compute heap bounds. Should be done by add_to_heap?      */
 318         least_ha = (word)(-1);
 319         greatest_ha = 0;
 320         for (i = 0; i < GC_n_heap_sects; ++i) {
 321             word sect_start = (word)GC_heap_sects[i].hs_start;
 322             word sect_end = sect_start + GC_heap_sects[i].hs_bytes;
 323             if (sect_start < least_ha) least_ha = sect_start;
 324             if (sect_end > greatest_ha) greatest_ha = sect_end;
 325         }
 326         if (greatest_ha < (word)GC_scratch_last_end_ptr)
 327             greatest_ha = (word)GC_scratch_last_end_ptr;
 328     for (;;) {
 329
 330         buf_ptr = parse_map_entry(buf_ptr, &start, &end, prot_buf, &maj_dev);
 331         if (buf_ptr == NULL) return;
 332
 333         if (prot_buf[1] == 'w') {
 334             /* This is a writable mapping.  Add it to           */
 335             /* the root set unless it is already otherwise      */
 336             /* accounted for.                                   */
 337             if (start <= (word)GC_stackbottom && end >= (word)GC_stackbottom) {
 338                 /* Stack mapping; discard       */
 339                 continue;
 340             }
 341             if (start <= datastart && end > datastart && maj_dev != 0) {
 342                 /* Main data segment; discard   */
 343                 continue;
 344             }
 345 #           ifdef THREADS
 346               if (GC_segment_is_thread_stack(start, end)) continue;
 347 #           endif
 348             /* The rest of this assumes that there is no mapping        */
 349             /* spanning the beginning of the data segment, or extending */
 350             /* beyond the entire heap at both ends.                     */
 351             /* Empirically these assumptions hold.                      */
 352
 353             if (start < (word)DATAEND && end > (word)DATAEND) {
 354                 /* Rld may use space at the end of the main data        */
 355                 /* segment.  Thus we add that in.                       */
 356                 start = (word)DATAEND;
 357             }
 358             if (start < least_ha && end > least_ha) {
 359                 end = least_ha;
 360             }
 361             if (start < greatest_ha && end > greatest_ha) {
 362                 start = greatest_ha;
 363             }
 364             if (start >= least_ha && end <= greatest_ha) continue;
 365             GC_add_roots_inner((char *)start, (char *)end, TRUE);
 366         }
 367      }
 368 }
 369
 370 //
 371 //  parse_map_entry parses an entry from /proc/self/maps so we can
 372 //  locate all writable data segments that belong to shared libraries.
 373 //  The format of one of these entries and the fields we care about
 374 //  is as follows:
 375 //  XXXXXXXX-XXXXXXXX r-xp 00000000 30:05 260537     name of mapping...\n
 376 //  ^^^^^^^^ ^^^^^^^^ ^^^^          ^^
 377 //  start    end      prot          maj_dev
 378 //  0        9        18            32
 379 //
 380 //  The parser is called with a pointer to the entry and the return value
 381 //  is either NULL or is advanced to the next entry(the byte after the
 382 //  trailing '\n'.)
 383 //
 384 #define OFFSET_MAP_START   0
 385 #define OFFSET_MAP_END     9
 386 #define OFFSET_MAP_PROT   18
 387 #define OFFSET_MAP_MAJDEV 32
 388
 389 static char *parse_map_entry(char *buf_ptr, word *start, word *end,
 390                              char *prot_buf, unsigned int *maj_dev)
 391 {
 392     int i;
 393     unsigned int val;
 394     char *tok;
 395
 396     if (buf_ptr == NULL || *buf_ptr == '\0') {
 397         return NULL;
 398     }
 399
 400     memcpy(prot_buf, buf_ptr+OFFSET_MAP_PROT, 4); // do the protections first
 401     prot_buf[4] = '\0';
 402
 403     if (prot_buf[1] == 'w') { // we can skip all of this if it's not writable
 404
 405         tok = buf_ptr;
 406         buf_ptr[OFFSET_MAP_START+8] = '\0';
 407         *start = strtoul(tok, NULL, 16);
 408
 409         tok = buf_ptr+OFFSET_MAP_END;
 410         buf_ptr[OFFSET_MAP_END+8] = '\0';
 411         *end = strtoul(tok, NULL, 16);
 412
 413         buf_ptr += OFFSET_MAP_MAJDEV;
 414         tok = buf_ptr;
 415         while (*buf_ptr != ':') buf_ptr++;
 416         *buf_ptr++ = '\0';
 417         *maj_dev = strtoul(tok, NULL, 16);
 418     }
 419
 420     while (*buf_ptr && *buf_ptr++ != '\n');
 421
 422     return buf_ptr;
 423 }
 424
 425 #endif /* USE_PROC_FOR_LIBRARIES */
 426
 427 #if !defined(USE_PROC_FOR_LIBRARIES)
 428 /* The following is the preferred way to walk dynamic libraries */
 429 /* For glibc 2.2.4+.  Unfortunately, it doesn't work for older  */
 430 /* versions.  Thanks to Jakub Jelinek for most of the code.     */
 431
 432 #include <stddef.h>
 433 #include <elf.h>
 434 #include <link.h>
 435
 436 # if defined(LINUX) /* Are others OK here, too? */ \
 437      && (__GLIBC__ > 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ > 2) \
 438          || (__GLIBC__ == 2 && __GLIBC_MINOR__ == 2 && defined(DT_CONFIG)))
 439
 440 /* We have the header files for a glibc that includes dl_iterate_phdr.  */
 441 /* It may still not be available in the library on the target system.   */
 442 /* Thus we also treat it as a weak symbol.                              */
 443 #define HAVE_DL_ITERATE_PHDR
 444
 445 static int GC_register_dynlib_callback(info, size, ptr)
 446      struct dl_phdr_info * info;
 447      size_t size;
 448      void * ptr;
 449 {
 450   const ElfW(Phdr) * p;
 451   char * start;
 452   register int i;
 453
 454   /* Make sure struct dl_phdr_info is at least as big as we need.  */
 455   if (size < offsetof (struct dl_phdr_info, dlpi_phnum)
 456       + sizeof (info->dlpi_phnum))
 457     return -1;
 458
 459   /* Skip the first object - it is the main program.  */
 460   if (*(int *)ptr == 0)
 461     {
 462       *(int *)ptr = 1;
 463       return 0;
 464     }
 465
 466   p = info->dlpi_phdr;
 467   for( i = 0; i < (int)(info->dlpi_phnum); ((i++),(p++)) ) {
 468     switch( p->p_type ) {
 469       case PT_LOAD:
 470         {
 471           if( !(p->p_flags & PF_W) ) break;
 472           start = ((char *)(p->p_vaddr)) + info->dlpi_addr;
 473           GC_add_roots_inner(start, start + p->p_memsz, TRUE);
 474         }
 475       break;
 476       default:
 477         break;
 478     }
 479   }
 480
 481   return 0;
 482 }
 483
 484 /* Return TRUE if we succeed, FALSE if dl_iterate_phdr wasn't there. */
 485
 486 #pragma weak dl_iterate_phdr
 487
 488 GC_bool GC_register_dynamic_libraries_dl_iterate_phdr()
 489 {
 490   int tmp = 0;
 491
 492   if (dl_iterate_phdr) {
 493     dl_iterate_phdr(GC_register_dynlib_callback, &tmp);
 494     return TRUE;
 495   } else {
 496     return FALSE;
 497   }
 498 }
 499
 500 # else /* !LINUX || version(glibc) < 2.2.4 */
 501
 502 /* Dynamic loading code for Linux running ELF. Somewhat tested on
 503  * Linux/x86, untested but hopefully should work on Linux/Alpha.
 504  * This code was derived from the Solaris/ELF support. Thanks to
 505  * whatever kind soul wrote that.  - Patrick Bridges */
 506
 507 /* This doesn't necessarily work in all cases, e.g. with preloaded
 508  * dynamic libraries.                                           */
 509
 510 #if defined(NETBSD)
 511 #  include <sys/exec_elf.h>
 512 #else
 513 #  include <elf.h>
 514 #endif
 515 #include <link.h>
 516
 517 # endif
 518
 519 /* Newer versions of Linux/Alpha and Linux/x86 define this macro.  We
 520  * define it for those older versions that don't.  */
 521 #  ifndef ElfW
 522 #    if !defined(ELF_CLASS) || ELF_CLASS == ELFCLASS32
 523 #      define ElfW(type) Elf32_##type
 524 #    else
 525 #      define ElfW(type) Elf64_##type
 526 #    endif
 527 #  endif
 528
 529 static struct link_map *
 530 GC_FirstDLOpenedLinkMap()
 531 {
 532 #   ifdef __GNUC__
 533 #     pragma weak _DYNAMIC
 534 #   endif
 535     extern ElfW(Dyn) _DYNAMIC[];
 536     ElfW(Dyn) *dp;
 537     struct r_debug *r;
 538     static struct link_map *cachedResult = 0;
 539
 540     if( _DYNAMIC == 0) {
 541         return(0);
 542     }
 543     if( cachedResult == 0 ) {
 544         int tag;
 545         for( dp = _DYNAMIC; (tag = dp->d_tag) != 0; dp++ ) {
 546             if( tag == DT_DEBUG ) {
 547                 struct link_map *lm
 548                         = ((struct r_debug *)(dp->d_un.d_ptr))->r_map;
 549                 if( lm != 0 ) cachedResult = lm->l_next; /* might be NIL */
 550                 break;
 551             }
 552         }
 553     }
 554     return cachedResult;
 555 }
 556
 557
 558 void GC_register_dynamic_libraries()
 559 {
 560   struct link_map *lm;
 561
 562
 563 # ifdef HAVE_DL_ITERATE_PHDR
 564     if (GC_register_dynamic_libraries_dl_iterate_phdr()) {
 565         return;
 566     }
 567 # endif
 568   lm = GC_FirstDLOpenedLinkMap();
 569   for (lm = GC_FirstDLOpenedLinkMap();
 570        lm != (struct link_map *) 0;  lm = lm->l_next)
 571     {
 572         ElfW(Ehdr) * e;
 573         ElfW(Phdr) * p;
 574         unsigned long offset;
 575         char * start;
 576         register int i;
 577
 578         e = (ElfW(Ehdr) *) lm->l_addr;
 579         p = ((ElfW(Phdr) *)(((char *)(e)) + e->e_phoff));
 580         offset = ((unsigned long)(lm->l_addr));
 581         for( i = 0; i < (int)(e->e_phnum); ((i++),(p++)) ) {
 582           switch( p->p_type ) {
 583             case PT_LOAD:
 584               {
 585                 if( !(p->p_flags & PF_W) ) break;
 586                 start = ((char *)(p->p_vaddr)) + offset;
 587                 GC_add_roots_inner(start, start + p->p_memsz, TRUE);
 588               }
 589               break;
 590             default:
 591               break;
 592           }
 593         }
 594     }
 595 }
 596
 597 #endif /* !USE_PROC_FOR_LIBRARIES */
 598
 599 #endif /* LINUX */
 600
 601 #if defined(IRIX5) || (defined(USE_PROC_FOR_LIBRARIES) && !defined(LINUX))
 602
 603 #include <sys/procfs.h>
 604 #include <sys/stat.h>
 605 #include <fcntl.h>
 606 #include <elf.h>
 607 #include <errno.h>
 608 #include <signal.h>  /* Only for the following test. */
 609 #ifndef _sigargs
 610 # define IRIX6
 611 #endif
 612
 613 extern void * GC_roots_present();
 614         /* The type is a lie, since the real type doesn't make sense here, */
 615         /* and we only test for NULL.                                      */
 616
 617 /* We use /proc to track down all parts of the address space that are   */
 618 /* mapped by the process, and throw out regions we know we shouldn't    */
 619 /* worry about.  This may also work under other SVR4 variants.          */
 620 void GC_register_dynamic_libraries()
 621 {
 622     static int fd = -1;
 623     char buf[30];
 624     static prmap_t * addr_map = 0;
 625     static int current_sz = 0;  /* Number of records currently in addr_map */
 626     static int needed_sz;       /* Required size of addr_map            */
 627     register int i;
 628     register long flags;
 629     register ptr_t start;
 630     register ptr_t limit;
 631     ptr_t heap_start = (ptr_t)HEAP_START;
 632     ptr_t heap_end = heap_start;
 633
 634 #   ifdef SUNOS5DL
 635 #     define MA_PHYS 0
 636 #   endif /* SUNOS5DL */
 637
 638     if (fd < 0) {
 639       sprintf(buf, "/proc/%d", getpid());
 640         /* The above generates a lint complaint, since pid_t varies.    */
 641         /* It's unclear how to improve this.                            */
 642       fd = open(buf, O_RDONLY);
 643       if (fd < 0) {
 644         ABORT("/proc open failed");
 645       }
 646     }
 647     if (ioctl(fd, PIOCNMAP, &needed_sz) < 0) {
 648         GC_err_printf2("fd = %d, errno = %d\n", fd, errno);
 649         ABORT("/proc PIOCNMAP ioctl failed");
 650     }
 651     if (needed_sz >= current_sz) {
 652         current_sz = needed_sz * 2 + 1;
 653                         /* Expansion, plus room for 0 record */
 654         addr_map = (prmap_t *)GC_scratch_alloc((word)
 655                                                 (current_sz * sizeof(prmap_t)));
 656     }
 657     if (ioctl(fd, PIOCMAP, addr_map) < 0) {
 658         GC_err_printf4("fd = %d, errno = %d, needed_sz = %d, addr_map = 0x%X\n",
 659                         fd, errno, needed_sz, addr_map);
 660         ABORT("/proc PIOCMAP ioctl failed");
 661     };
 662     if (GC_n_heap_sects > 0) {
 663         heap_end = GC_heap_sects[GC_n_heap_sects-1].hs_start
 664                         + GC_heap_sects[GC_n_heap_sects-1].hs_bytes;
 665         if (heap_end < GC_scratch_last_end_ptr) heap_end = GC_scratch_last_end_ptr;
 666     }
 667     for (i = 0; i < needed_sz; i++) {
 668         flags = addr_map[i].pr_mflags;
 669         if ((flags & (MA_BREAK | MA_STACK | MA_PHYS)) != 0) goto irrelevant;
 670         if ((flags & (MA_READ | MA_WRITE)) != (MA_READ | MA_WRITE))
 671             goto irrelevant;
 672           /* The latter test is empirically useless in very old Irix    */
 673           /* versions.  Other than the                                  */
 674           /* main data and stack segments, everything appears to be     */
 675           /* mapped readable, writable, executable, and shared(!!).     */
 676           /* This makes no sense to me. - HB                            */
 677         start = (ptr_t)(addr_map[i].pr_vaddr);
 678         if (GC_roots_present(start)) goto irrelevant;
 679         if (start < heap_end && start >= heap_start)
 680                 goto irrelevant;
 681 #       ifdef MMAP_STACKS
 682           if (GC_is_thread_stack(start)) goto irrelevant;
 683 #       endif /* MMAP_STACKS */
 684
 685         limit = start + addr_map[i].pr_size;
 686         /* The following seemed to be necessary for very old versions   */
 687         /* of Irix, but it has been reported to discard relevant        */
 688         /* segments under Irix 6.5.                                     */
 689 #       ifndef IRIX6
 690           if (addr_map[i].pr_off == 0 && strncmp(start, ELFMAG, 4) == 0) {
 691             /* Discard text segments, i.e. 0-offset mappings against    */
 692             /* executable files which appear to have ELF headers.       */
 693             caddr_t arg;
 694             int obj;
 695 #           define MAP_IRR_SZ 10
 696             static ptr_t map_irr[MAP_IRR_SZ];
 697                                         /* Known irrelevant map entries */
 698             static int n_irr = 0;
 699             struct stat buf;
 700             register int i;
 701
 702             for (i = 0; i < n_irr; i++) {
 703                 if (map_irr[i] == start) goto irrelevant;
 704             }
 705             arg = (caddr_t)start;
 706             obj = ioctl(fd, PIOCOPENM, &arg);
 707             if (obj >= 0) {
 708                 fstat(obj, &buf);
 709                 close(obj);
 710                 if ((buf.st_mode & 0111) != 0) {
 711                     if (n_irr < MAP_IRR_SZ) {
 712                         map_irr[n_irr++] = start;
 713                     }
 714                     goto irrelevant;
 715                 }
 716             }
 717           }
 718 #       endif /* !IRIX6 */
 719         GC_add_roots_inner(start, limit, TRUE);
 720       irrelevant: ;
 721     }
 722     /* Dont keep cached descriptor, for now.  Some kernels don't like us */
 723     /* to keep a /proc file descriptor around during kill -9.            */
 724         if (close(fd) < 0) ABORT("Couldnt close /proc file");
 725         fd = -1;
 726 }
 727
 728 # endif /* USE_PROC || IRIX5 */
 729
 730 # if defined(MSWIN32) || defined(MSWINCE)
 731
 732 # define WIN32_LEAN_AND_MEAN
 733 # define NOSERVICE
 734 # include <windows.h>
 735 # include <stdlib.h>
 736
 737   /* We traverse the entire address space and register all segments     */
 738   /* that could possibly have been written to.                          */
 739
 740   extern GC_bool GC_is_heap_base (ptr_t p);
 741
 742 # ifdef GC_WIN32_THREADS
 743     extern void GC_get_next_stack(char *start, char **lo, char **hi);
 744     void GC_cond_add_roots(char *base, char * limit)
 745     {
 746       char * curr_base = base;
 747       char * next_stack_lo;
 748       char * next_stack_hi;
 749
 750       if (base == limit) return;
 751       for(;;) {
 752           GC_get_next_stack(curr_base, &next_stack_lo, &next_stack_hi);
 753           if (next_stack_lo >= limit) break;
 754           GC_add_roots_inner(curr_base, next_stack_lo, TRUE);
 755           curr_base = next_stack_hi;
 756       }
 757       if (curr_base < limit) GC_add_roots_inner(curr_base, limit, TRUE);
 758     }
 759 # else
 760     void GC_cond_add_roots(char *base, char * limit)
 761     {
 762       char dummy;
 763       char * stack_top
 764          = (char *) ((word)(&dummy) & ~(GC_sysinfo.dwAllocationGranularity-1));
 765       if (base == limit) return;
 766       if (limit > stack_top && base < GC_stackbottom) {
 767           /* Part of the stack; ignore it. */
 768           return;
 769       }
 770       GC_add_roots_inner(base, limit, TRUE);
 771     }
 772 # endif
 773
 774 # ifndef MSWINCE
 775   extern GC_bool GC_win32s;
 776 # endif
 777
 778   void GC_register_dynamic_libraries()
 779   {
 780     MEMORY_BASIC_INFORMATION buf;
 781     DWORD result;
 782     DWORD protect;
 783     LPVOID p;
 784     char * base;
 785     char * limit, * new_limit;
 786
 787 #   ifdef MSWIN32
 788       if (GC_win32s) return;
 789 #   endif
 790     base = limit = p = GC_sysinfo.lpMinimumApplicationAddress;
 791 #   if defined(MSWINCE) && !defined(_WIN32_WCE_EMULATION)
 792     /* Only the first 32 MB of address space belongs to the current process */
 793     while (p < (LPVOID)0x02000000) {
 794         result = VirtualQuery(p, &buf, sizeof(buf));
 795         if (result == 0) {
 796             /* Page is free; advance to the next possible allocation base */
 797             new_limit = (char *)
 798                 (((DWORD) p + GC_sysinfo.dwAllocationGranularity)
 799                  & ~(GC_sysinfo.dwAllocationGranularity-1));
 800         } else
 801 #   else
 802     while (p < GC_sysinfo.lpMaximumApplicationAddress) {
 803         result = VirtualQuery(p, &buf, sizeof(buf));
 804 #   endif
 805         {
 806             if (result != sizeof(buf)) {
 807                 ABORT("Weird VirtualQuery result");
 808             }
 809             new_limit = (char *)p + buf.RegionSize;
 810             protect = buf.Protect;
 811             if (buf.State == MEM_COMMIT
 812                 && (protect == PAGE_EXECUTE_READWRITE
 813                     || protect == PAGE_READWRITE)
 814                 && !GC_is_heap_base(buf.AllocationBase)) {
 815                 if ((char *)p != limit) {
 816                     GC_cond_add_roots(base, limit);
 817                     base = p;
 818                 }
 819                 limit = new_limit;
 820             }
 821         }
 822         if (p > (LPVOID)new_limit /* overflow */) break;
 823         p = (LPVOID)new_limit;
 824     }
 825     GC_cond_add_roots(base, limit);
 826   }
 827
 828 #endif /* MSWIN32 || MSWINCE */
 829
 830 #if defined(ALPHA) && defined(OSF1)
 831
 832 #include <loader.h>
 833
 834 void GC_register_dynamic_libraries()
 835 {
 836   int status;
 837   ldr_process_t mypid;
 838
 839   /* module */
 840     ldr_module_t moduleid = LDR_NULL_MODULE;
 841     ldr_module_info_t moduleinfo;
 842     size_t moduleinfosize = sizeof(moduleinfo);
 843     size_t modulereturnsize;
 844
 845   /* region */
 846     ldr_region_t region;
 847     ldr_region_info_t regioninfo;
 848     size_t regioninfosize = sizeof(regioninfo);
 849     size_t regionreturnsize;
 850
 851   /* Obtain id of this process */
 852     mypid = ldr_my_process();
 853
 854   /* For each module */
 855     while (TRUE) {
 856
 857       /* Get the next (first) module */
 858         status = ldr_next_module(mypid, &moduleid);
 859
 860       /* Any more modules? */
 861         if (moduleid == LDR_NULL_MODULE)
 862             break;    /* No more modules */
 863
 864       /* Check status AFTER checking moduleid because */
 865       /* of a bug in the non-shared ldr_next_module stub */
 866         if (status != 0 ) {
 867             GC_printf1("dynamic_load: status = %ld\n", (long)status);
 868             {
 869                 extern char *sys_errlist[];
 870                 extern int sys_nerr;
 871                 extern int errno;
 872                 if (errno <= sys_nerr) {
 873                     GC_printf1("dynamic_load: %s\n", (long)sys_errlist[errno]);
 874                } else {
 875                     GC_printf1("dynamic_load: %d\n", (long)errno);
 876                 }
 877         }
 878             ABORT("ldr_next_module failed");
 879          }
 880
 881       /* Get the module information */
 882         status = ldr_inq_module(mypid, moduleid, &moduleinfo,
 883                                 moduleinfosize, &modulereturnsize);
 884         if (status != 0 )
 885             ABORT("ldr_inq_module failed");
 886
 887       /* is module for the main program (i.e. nonshared portion)? */
 888           if (moduleinfo.lmi_flags & LDR_MAIN)
 889               continue;    /* skip the main module */
 890
 891 #     ifdef VERBOSE
 892           GC_printf("---Module---\n");
 893           GC_printf("Module ID            = %16ld\n", moduleinfo.lmi_modid);
 894           GC_printf("Count of regions     = %16d\n", moduleinfo.lmi_nregion);
 895           GC_printf("flags for module     = %16lx\n", moduleinfo.lmi_flags);
 896           GC_printf("pathname of module   = \"%s\"\n", moduleinfo.lmi_name);
 897 #     endif
 898
 899       /* For each region in this module */
 900         for (region = 0; region < moduleinfo.lmi_nregion; region++) {
 901
 902           /* Get the region information */
 903             status = ldr_inq_region(mypid, moduleid, region, &regioninfo,
 904                                     regioninfosize, &regionreturnsize);
 905             if (status != 0 )
 906                 ABORT("ldr_inq_region failed");
 907
 908           /* only process writable (data) regions */
 909             if (! (regioninfo.lri_prot & LDR_W))
 910                 continue;
 911
 912 #         ifdef VERBOSE
 913               GC_printf("--- Region ---\n");
 914               GC_printf("Region number    = %16ld\n",
 915                         regioninfo.lri_region_no);
 916               GC_printf("Protection flags = %016x\n",  regioninfo.lri_prot);
 917               GC_printf("Virtual address  = %16p\n",   regioninfo.lri_vaddr);
 918               GC_printf("Mapped address   = %16p\n",   regioninfo.lri_mapaddr);
 919               GC_printf("Region size      = %16ld\n",  regioninfo.lri_size);
 920               GC_printf("Region name      = \"%s\"\n", regioninfo.lri_name);
 921 #         endif
 922
 923           /* register region as a garbage collection root */
 924             GC_add_roots_inner (
 925                 (char *)regioninfo.lri_mapaddr,
 926                 (char *)regioninfo.lri_mapaddr + regioninfo.lri_size,
 927                 TRUE);
 928
 929         }
 930     }
 931 }
 932 #endif
 933
 934 #if defined(HPUX)
 935
 936 #include <errno.h>
 937 #include <dl.h>
 938
 939 extern int errno;
 940 extern char *sys_errlist[];
 941 extern int sys_nerr;
 942
 943 void GC_register_dynamic_libraries()
 944 {
 945   int status;
 946   int index = 1; /* Ordinal position in shared library search list */
 947   struct shl_descriptor *shl_desc; /* Shared library info, see dl.h */
 948
 949   /* For each dynamic library loaded */
 950     while (TRUE) {
 951
 952       /* Get info about next shared library */
 953         status = shl_get(index, &shl_desc);
 954
 955       /* Check if this is the end of the list or if some error occured */
 956         if (status != 0) {
 957 #        ifdef GC_HPUX_THREADS
 958            /* I've seen errno values of 0.  The man page is not clear   */
 959            /* as to whether errno should get set on a -1 return.        */
 960            break;
 961 #        else
 962           if (errno == EINVAL) {
 963               break; /* Moved past end of shared library list --> finished */
 964           } else {
 965               if (errno <= sys_nerr) {
 966                     GC_printf1("dynamic_load: %s\n", (long) sys_errlist[errno]);
 967               } else {
 968                     GC_printf1("dynamic_load: %d\n", (long) errno);
 969               }
 970               ABORT("shl_get failed");
 971           }
 972 #        endif
 973         }
 974
 975 #     ifdef VERBOSE
 976           GC_printf0("---Shared library---\n");
 977           GC_printf1("\tfilename        = \"%s\"\n", shl_desc->filename);
 978           GC_printf1("\tindex           = %d\n", index);
 979           GC_printf1("\thandle          = %08x\n",
 980                                         (unsigned long) shl_desc->handle);
 981           GC_printf1("\ttext seg. start = %08x\n", shl_desc->tstart);
 982           GC_printf1("\ttext seg. end   = %08x\n", shl_desc->tend);
 983           GC_printf1("\tdata seg. start = %08x\n", shl_desc->dstart);
 984           GC_printf1("\tdata seg. end   = %08x\n", shl_desc->dend);
 985           GC_printf1("\tref. count      = %lu\n", shl_desc->ref_count);
 986 #     endif
 987
 988       /* register shared library's data segment as a garbage collection root */
 989         GC_add_roots_inner((char *) shl_desc->dstart,
 990                            (char *) shl_desc->dend, TRUE);
 991
 992         index++;
 993     }
 994 }
 995 #endif /* HPUX */
 996
 997 #ifdef RS6000
 998 #pragma alloca
 999 #include <sys/ldr.h>
1000 #include <sys/errno.h>
1001 void GC_register_dynamic_libraries()
1002 {
1003         int len;
1004         char *ldibuf;
1005         int ldibuflen;
1006         struct ld_info *ldi;
1007
1008         ldibuf = alloca(ldibuflen = 8192);
1009
1010         while ( (len = loadquery(L_GETINFO,ldibuf,ldibuflen)) < 0) {
1011                 if (errno != ENOMEM) {
1012                         ABORT("loadquery failed");
1013                 }
1014                 ldibuf = alloca(ldibuflen *= 2);
1015         }
1016
1017         ldi = (struct ld_info *)ldibuf;
1018         while (ldi) {
1019                 len = ldi->ldinfo_next;
1020                 GC_add_roots_inner(
1021                                 ldi->ldinfo_dataorg,
1022                                 (unsigned long)ldi->ldinfo_dataorg
1023                                 + ldi->ldinfo_datasize,
1024                                 TRUE);
1025                 ldi = len ? (struct ld_info *)((char *)ldi + len) : 0;
1026         }
1027 }
1028 #endif /* RS6000 */
1029
1030
1031
1032 #else /* !DYNAMIC_LOADING */
1033
1034 #ifdef PCR
1035
1036 #   include "il/PCR_IL.h"
1037 #   include "th/PCR_ThCtl.h"
1038 #   include "mm/PCR_MM.h"
1039
1040 void GC_register_dynamic_libraries()
1041 {
1042     /* Add new static data areas of dynamically loaded modules. */
1043         {
1044           PCR_IL_LoadedFile * p = PCR_IL_GetLastLoadedFile();
1045           PCR_IL_LoadedSegment * q;
1046
1047           /* Skip uncommited files */
1048           while (p != NIL && !(p -> lf_commitPoint)) {
1049               /* The loading of this file has not yet been committed    */
1050               /* Hence its description could be inconsistent.           */
1051               /* Furthermore, it hasn't yet been run.  Hence its data   */
1052               /* segments can't possibly reference heap allocated       */
1053               /* objects.                                               */
1054               p = p -> lf_prev;
1055           }
1056           for (; p != NIL; p = p -> lf_prev) {
1057             for (q = p -> lf_ls; q != NIL; q = q -> ls_next) {
1058               if ((q -> ls_flags & PCR_IL_SegFlags_Traced_MASK)
1059                   == PCR_IL_SegFlags_Traced_on) {
1060                 GC_add_roots_inner
1061                         ((char *)(q -> ls_addr),
1062                          (char *)(q -> ls_addr) + q -> ls_bytes,
1063                          TRUE);
1064               }
1065             }
1066           }
1067         }
1068 }
1069
1070
1071 #else /* !PCR */
1072
1073 void GC_register_dynamic_libraries(){}
1074
1075 int GC_no_dynamic_loading;
1076
1077 #endif /* !PCR */
1078 #endif /* !DYNAMIC_LOADING */