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