forked from gcc-mirror/gcc
-
Notifications
You must be signed in to change notification settings - Fork 0
/
Copy pathdyn_load.c
1505 lines (1304 loc) · 43.6 KB
/
dyn_load.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
/*
* Copyright (c) 1991-1994 by Xerox Corporation. All rights reserved.
* Copyright (c) 1997 by Silicon Graphics. All rights reserved.
*
* THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
* OR IMPLIED. ANY USE IS AT YOUR OWN RISK.
*
* Permission is hereby granted to use or copy this program
* for any purpose, provided the above notices are retained on all copies.
* Permission to modify the code and to distribute modified code is granted,
* provided the above notices are retained, and a notice that the code was
* modified is included with the above copyright notice.
*
* Original author: Bill Janssen
* Heavily modified by Hans Boehm and others
*/
/*
* This is incredibly OS specific code for tracking down data sections in
* dynamic libraries. There appears to be no way of doing this quickly
* without groveling through undocumented data structures. We would argue
* that this is a bug in the design of the dlopen interface. THIS CODE
* MAY BREAK IN FUTURE OS RELEASES. If this matters to you, don't hesitate
* to let your vendor know ...
*
* None of this is safe with dlclose and incremental collection.
* But then not much of anything is safe in the presence of dlclose.
*/
#if (defined(__linux__) || defined(__GLIBC__) || defined(__GNU__)) \
&& !defined(_GNU_SOURCE)
/* Can't test LINUX, since this must be define before other includes */
# define _GNU_SOURCE
#endif
#if !defined(MACOS) && !defined(_WIN32_WCE)
# include <sys/types.h>
#endif
#include "private/gc_priv.h"
/* BTL: avoid circular redefinition of dlopen if GC_SOLARIS_THREADS defined */
# if (defined(GC_PTHREADS) || defined(GC_SOLARIS_THREADS)) \
&& defined(dlopen) && !defined(GC_USE_LD_WRAP)
/* To support threads in Solaris, gc.h interposes on dlopen by */
/* defining "dlopen" to be "GC_dlopen", which is implemented below. */
/* However, both GC_FirstDLOpenedLinkMap() and GC_dlopen() use the */
/* real system dlopen() in their implementation. We first remove */
/* gc.h's dlopen definition and restore it later, after GC_dlopen(). */
# undef dlopen
# define GC_must_restore_redefined_dlopen
# else
# undef GC_must_restore_redefined_dlopen
# endif
#if (defined(DYNAMIC_LOADING) \
|| defined(MSWIN32) \
|| defined(MSWINCE) \
|| defined(CYGWIN32)) \
&& !defined(PCR)
#if !defined(SUNOS4) && !defined(SUNOS5DL) && !defined(IRIX5) && \
!defined(MSWIN32) && !defined(MSWINCE) && !defined(CYGWIN32) && \
!(defined(ALPHA) && defined(OSF1)) && \
!defined(HPUX) && !(defined(LINUX) && defined(__ELF__)) && \
!defined(RS6000) && !defined(SCO_ELF) && !defined(DGUX) && \
!(defined(FREEBSD) && defined(__ELF__)) && \
!(defined(NETBSD) && defined(__ELF__)) && !defined(HURD) && \
!defined(DARWIN)
--> We only know how to find data segments of dynamic libraries for the
--> above. Additional SVR4 variants might not be too
--> hard to add.
#endif
#include <stdio.h>
#ifdef SUNOS5DL
# include <sys/elf.h>
# include <dlfcn.h>
# include <link.h>
#endif
#ifdef SUNOS4
# include <dlfcn.h>
# include <link.h>
# include <a.out.h>
/* struct link_map field overrides */
# define l_next lm_next
# define l_addr lm_addr
# define l_name lm_name
#endif
#ifdef IRIX5
# include <elf.h>
# if _MIPS_SIM == _MIPS_SIM_ABI32 /* O32 ABI */
/* Don't include <obj_list.h> here. */
# include <obj.h>
# else /* N32 or N64 ABIs */
# include <objlist.h>
# endif
#endif
#if defined(NETBSD)
# include <machine/elf_machdep.h>
# define ELFSIZE ARCH_ELFSIZE
#endif
#if defined(LINUX) && defined(__ELF__) || defined(SCO_ELF) || \
(defined(FREEBSD) && defined(__ELF__)) || defined(DGUX) || \
(defined(NETBSD) && defined(__ELF__)) || defined(HURD)
# include <stddef.h>
# include <elf.h>
# include <link.h>
#endif
/* Newer versions of GNU/Linux define this macro. We
* define it similarly for any ELF systems that don't. */
# ifndef ElfW
# if defined(FREEBSD)
# if __ELF_WORD_SIZE == 32
# define ElfW(type) Elf32_##type
# else
# define ElfW(type) Elf64_##type
# endif
# else
# ifdef NETBSD
# if ELFSIZE == 32
# define ElfW(type) Elf32_##type
# else
# define ElfW(type) Elf64_##type
# endif
# else
# if !defined(ELF_CLASS) || ELF_CLASS == ELFCLASS32
# define ElfW(type) Elf32_##type
# else
# define ElfW(type) Elf64_##type
# endif
# endif
# endif
# endif
/* An user-supplied routine that is called to determine if a DSO must
be scanned by the gc. */
static int (*GC_has_static_roots)(const char *, void *, size_t);
/* Register the routine. */
void
GC_register_has_static_roots_callback
(int (*callback)(const char *, void *, size_t))
{
GC_has_static_roots = callback;
}
#if defined(SUNOS5DL) && !defined(USE_PROC_FOR_LIBRARIES)
#ifdef LINT
Elf32_Dyn _DYNAMIC;
#endif
#define obj_offset(lm) ((unsigned long)(lm->l_addr))
static struct link_map *
GC_FirstDLOpenedLinkMap()
{
extern ElfW(Dyn) _DYNAMIC;
ElfW(Dyn) *dp;
struct r_debug *r;
static struct link_map * cachedResult = 0;
static ElfW(Dyn) *dynStructureAddr = 0;
/* BTL: added to avoid Solaris 5.3 ld.so _DYNAMIC bug */
# ifdef SUNOS53_SHARED_LIB
/* BTL: Avoid the Solaris 5.3 bug that _DYNAMIC isn't being set */
/* up properly in dynamically linked .so's. This means we have */
/* to use its value in the set of original object files loaded */
/* at program startup. */
if( dynStructureAddr == 0 ) {
void* startupSyms = dlopen(0, RTLD_LAZY);
dynStructureAddr = (ElfW(Dyn)*)dlsym(startupSyms, "_DYNAMIC");
}
# else
dynStructureAddr = &_DYNAMIC;
# endif
if( dynStructureAddr == 0) {
return(0);
}
if( cachedResult == 0 ) {
int tag;
for( dp = ((ElfW(Dyn) *)(&_DYNAMIC)); (tag = dp->d_tag) != 0; dp++ ) {
if( tag == DT_DEBUG ) {
struct link_map *lm
= ((struct r_debug *)(dp->d_un.d_ptr))->r_map;
if( lm != 0 ) cachedResult = lm->l_next; /* might be NIL */
break;
}
}
}
return cachedResult;
}
#endif /* SUNOS5DL ... */
/* BTL: added to fix circular dlopen definition if GC_SOLARIS_THREADS defined */
# if defined(GC_must_restore_redefined_dlopen)
# define dlopen GC_dlopen
# endif
#if defined(SUNOS4) && !defined(USE_PROC_FOR_LIBRARIES)
#ifdef LINT
struct link_dynamic _DYNAMIC;
#endif
#define obj_offset(lm) ((unsigned long)(lm->l_addr))
static struct link_map *
GC_FirstDLOpenedLinkMap()
{
extern struct link_dynamic _DYNAMIC;
if( &_DYNAMIC == 0) {
return(0);
}
return(_DYNAMIC.ld_un.ld_1->ld_loaded);
}
/* Return the address of the ld.so allocated common symbol */
/* with the least address, or 0 if none. */
static ptr_t GC_first_common()
{
ptr_t result = 0;
extern struct link_dynamic _DYNAMIC;
struct rtc_symb * curr_symbol;
if( &_DYNAMIC == 0) {
return(0);
}
curr_symbol = _DYNAMIC.ldd -> ldd_cp;
for (; curr_symbol != 0; curr_symbol = curr_symbol -> rtc_next) {
if (result == 0
|| (ptr_t)(curr_symbol -> rtc_sp -> n_value) < result) {
result = (ptr_t)(curr_symbol -> rtc_sp -> n_value);
}
}
return(result);
}
#endif /* SUNOS4 ... */
#if defined(IRIX5) && !defined(USE_PROC_FOR_LIBRARIES)
/* Provide struct link map. */
# if _MIPS_SIM == _MIPS_SIM_ABI32 /* O32 ABI */
/* Provide our own version of struct obj_list in <obj_list.h> with
correctly typed data member. */
struct obj_list {
struct obj *data;
struct obj_list *next;
struct obj_list *prev;
} objList;
struct link_map {
objList l_ol;
};
extern objList *__rld_obj_head;
/* Map field names */
# define l_next l_ol.next
# define l_addr l_ol.data->o_pelfhdr
# define obj_offset(lm) \
((unsigned long)(lm->l_ol.o_praw - (char *)lm->l_ol.o_base_address))
# else /* N32 or N64 ABIs */
struct link_map {
ElfW(Obj_Info) l_oi;
};
extern ElfW(Obj_Info) *__rld_obj_head;
/* Map field names */
# define l_next l_oi.oi_next
# define l_addr l_oi.oi_ehdr
/* See gdb/solib-irix.c (fetch_lm_info). */
# define obj_offset(lm) \
((unsigned long)(lm->l_oi.oi_ehdr - lm->l_oi.oi_orig_ehdr))
# endif
static struct link_map *
GC_FirstDLOpenedLinkMap()
{
return (struct link_map *)__rld_obj_head;
}
#endif /* IRIX5 ... */
# if defined(SUNOS4) || defined(SUNOS5DL) || defined(IRIX5)
/* Add dynamic library data sections to the root set. */
# if !defined(PCR) \
&& !defined(GC_SOLARIS_PTHREADS) && !defined(GC_IRIX_THREADS) \
&& defined(THREADS)
# ifndef SRC_M3
--> fix mutual exclusion with dlopen
# endif /* We assume M3 programs don't call dlopen for now */
# endif
# ifndef USE_PROC_FOR_LIBRARIES
void GC_register_dynamic_libraries()
{
struct link_map *lm = GC_FirstDLOpenedLinkMap();
for (lm = GC_FirstDLOpenedLinkMap();
lm != (struct link_map *) 0; lm = (struct link_map *) lm->l_next)
{
# ifdef SUNOS4
struct exec *e;
e = (struct exec *) lm->lm_addr;
GC_add_roots_inner(
((char *) (N_DATOFF(*e) + lm->lm_addr)),
((char *) (N_BSSADDR(*e) + e->a_bss + lm->lm_addr)),
TRUE);
# endif
# if defined(SUNOS5DL) || defined(IRIX5)
ElfW(Ehdr) * e;
ElfW(Phdr) * p;
unsigned long offset;
char * start;
register int i;
e = (ElfW(Ehdr) *) lm->l_addr;
p = ((ElfW(Phdr) *)(((char *)(e)) + e->e_phoff));
offset = obj_offset(lm);
for( i = 0; i < (int)(e->e_phnum); ((i++),(p++)) ) {
switch( p->p_type ) {
case PT_LOAD:
{
if( !(p->p_flags & PF_W) ) break;
start = ((char *)(p->p_vaddr)) + offset;
GC_add_roots_inner(
start,
start + p->p_memsz,
TRUE
);
}
break;
default:
break;
}
}
# endif
}
# ifdef SUNOS4
{
static ptr_t common_start = 0;
ptr_t common_end;
extern ptr_t GC_find_limit();
if (common_start == 0) common_start = GC_first_common();
if (common_start != 0) {
common_end = GC_find_limit(common_start, TRUE);
GC_add_roots_inner((char *)common_start, (char *)common_end, TRUE);
}
}
# endif
}
# endif /* !USE_PROC ... */
# endif /* SUNOS */
#if defined(LINUX) && defined(__ELF__) || defined(SCO_ELF) || \
(defined(FREEBSD) && defined(__ELF__)) || defined(DGUX) || \
(defined(NETBSD) && defined(__ELF__)) || defined(HURD)
#ifdef USE_PROC_FOR_LIBRARIES
#include <string.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#define MAPS_BUF_SIZE (32*1024)
extern ssize_t GC_repeat_read(int fd, char *buf, size_t count);
/* Repeatedly read until buffer is filled, or EOF is encountered */
/* Defined in os_dep.c. */
char *GC_parse_map_entry(char *buf_ptr, word *start, word *end,
char *prot_buf, unsigned int *maj_dev);
word GC_apply_to_maps(word (*fn)(char *));
/* From os_dep.c */
word GC_register_map_entries(char *maps)
{
char prot_buf[5];
char *buf_ptr = maps;
int count;
word start, end;
unsigned int maj_dev;
word least_ha, greatest_ha;
unsigned i;
word datastart = (word)(DATASTART);
/* Compute heap bounds. FIXME: Should be done by add_to_heap? */
least_ha = (word)(-1);
greatest_ha = 0;
for (i = 0; i < GC_n_heap_sects; ++i) {
word sect_start = (word)GC_heap_sects[i].hs_start;
word sect_end = sect_start + GC_heap_sects[i].hs_bytes;
if (sect_start < least_ha) least_ha = sect_start;
if (sect_end > greatest_ha) greatest_ha = sect_end;
}
if (greatest_ha < (word)GC_scratch_last_end_ptr)
greatest_ha = (word)GC_scratch_last_end_ptr;
for (;;) {
buf_ptr = GC_parse_map_entry(buf_ptr, &start, &end, prot_buf, &maj_dev);
if (buf_ptr == NULL) return 1;
if (prot_buf[1] == 'w') {
/* This is a writable mapping. Add it to */
/* the root set unless it is already otherwise */
/* accounted for. */
if (start <= (word)GC_stackbottom && end >= (word)GC_stackbottom) {
/* Stack mapping; discard */
continue;
}
# ifdef THREADS
if (GC_segment_is_thread_stack(start, end)) continue;
# endif
/* We no longer exclude the main data segment. */
if (start < least_ha && end > least_ha) {
end = least_ha;
}
if (start < greatest_ha && end > greatest_ha) {
start = greatest_ha;
}
if (start >= least_ha && end <= greatest_ha) continue;
GC_add_roots_inner((char *)start, (char *)end, TRUE);
}
}
return 1;
}
void GC_register_dynamic_libraries()
{
if (!GC_apply_to_maps(GC_register_map_entries))
ABORT("Failed to read /proc for library registration.");
}
/* We now take care of the main data segment ourselves: */
GC_bool GC_register_main_static_data()
{
return FALSE;
}
# define HAVE_REGISTER_MAIN_STATIC_DATA
#endif /* USE_PROC_FOR_LIBRARIES */
#if !defined(USE_PROC_FOR_LIBRARIES)
/* The following is the preferred way to walk dynamic libraries */
/* For glibc 2.2.4+. Unfortunately, it doesn't work for older */
/* versions. Thanks to Jakub Jelinek for most of the code. */
# if (defined(LINUX) || defined (__GLIBC__)) /* Are others OK here, too? */ \
&& (__GLIBC__ > 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ > 2) \
|| (__GLIBC__ == 2 && __GLIBC_MINOR__ == 2 && defined(DT_CONFIG)))
/* We have the header files for a glibc that includes dl_iterate_phdr. */
/* It may still not be available in the library on the target system. */
/* Thus we also treat it as a weak symbol. */
#define HAVE_DL_ITERATE_PHDR
#pragma weak dl_iterate_phdr
#endif
# if (defined(FREEBSD) && __FreeBSD__ >= 7)
/* On the FreeBSD system, any target system at major version 7 shall */
/* have dl_iterate_phdr; therefore, we need not make it weak as above. */
#define HAVE_DL_ITERATE_PHDR
#endif
#if defined(HAVE_DL_ITERATE_PHDR)
static int GC_register_dynlib_callback(info, size, ptr)
struct dl_phdr_info * info;
size_t size;
void * ptr;
{
const ElfW(Phdr) * p;
char * start;
register int i;
/* Make sure struct dl_phdr_info is at least as big as we need. */
if (size < offsetof (struct dl_phdr_info, dlpi_phnum)
+ sizeof (info->dlpi_phnum))
return -1;
p = info->dlpi_phdr;
for( i = 0; i < (int)(info->dlpi_phnum); ((i++),(p++)) ) {
switch( p->p_type ) {
case PT_LOAD:
{
if( !(p->p_flags & PF_W) ) break;
start = ((char *)(p->p_vaddr)) + info->dlpi_addr;
if (GC_has_static_roots
&& !GC_has_static_roots(info->dlpi_name, start, p->p_memsz))
break;
GC_add_roots_inner(start, start + p->p_memsz, TRUE);
}
break;
default:
break;
}
}
* (int *)ptr = 1; /* Signal that we were called */
return 0;
}
/* Return TRUE if we succeed, FALSE if dl_iterate_phdr wasn't there. */
GC_bool GC_register_dynamic_libraries_dl_iterate_phdr()
{
if (dl_iterate_phdr) {
int did_something = 0;
dl_iterate_phdr(GC_register_dynlib_callback, &did_something);
if (!did_something) {
/* dl_iterate_phdr may forget the static data segment in */
/* statically linked executables. */
GC_add_roots_inner(DATASTART, (char *)(DATAEND), TRUE);
# if defined(DATASTART2)
GC_add_roots_inner(DATASTART2, (char *)(DATAEND2), TRUE);
# endif
}
return TRUE;
} else {
return FALSE;
}
}
/* Do we need to separately register the main static data segment? */
GC_bool GC_register_main_static_data()
{
return (dl_iterate_phdr == 0);
}
#define HAVE_REGISTER_MAIN_STATIC_DATA
# else /* !LINUX || version(glibc) < 2.2.4 */
/* Dynamic loading code for Linux running ELF. Somewhat tested on
* Linux/x86, untested but hopefully should work on Linux/Alpha.
* This code was derived from the Solaris/ELF support. Thanks to
* whatever kind soul wrote that. - Patrick Bridges */
/* This doesn't necessarily work in all cases, e.g. with preloaded
* dynamic libraries. */
#if defined(NETBSD)
# include <sys/exec_elf.h>
/* for compatibility with 1.4.x */
# ifndef DT_DEBUG
# define DT_DEBUG 21
# endif
# ifndef PT_LOAD
# define PT_LOAD 1
# endif
# ifndef PF_W
# define PF_W 2
# endif
#else
# include <elf.h>
#endif
#include <link.h>
# endif
#ifdef __GNUC__
# pragma weak _DYNAMIC
#endif
extern ElfW(Dyn) _DYNAMIC[];
static struct link_map *
GC_FirstDLOpenedLinkMap()
{
ElfW(Dyn) *dp;
static struct link_map *cachedResult = 0;
if( _DYNAMIC == 0) {
return(0);
}
if( cachedResult == 0 ) {
int tag;
for( dp = _DYNAMIC; (tag = dp->d_tag) != 0; dp++ ) {
/* FIXME: The DT_DEBUG header is not mandated by the */
/* ELF spec. This code appears to be dependent on */
/* idiosynchracies of older GNU tool chains. If this code */
/* fails for you, the real problem is probably that it is */
/* being used at all. You should be getting the */
/* dl_iterate_phdr version. */
if( tag == DT_DEBUG ) {
struct link_map *lm
= ((struct r_debug *)(dp->d_un.d_ptr))->r_map;
if( lm != 0 ) cachedResult = lm->l_next; /* might be NIL */
break;
}
}
}
return cachedResult;
}
void GC_register_dynamic_libraries()
{
struct link_map *lm;
# ifdef HAVE_DL_ITERATE_PHDR
if (GC_register_dynamic_libraries_dl_iterate_phdr()) {
return;
}
# endif
lm = GC_FirstDLOpenedLinkMap();
for (lm = GC_FirstDLOpenedLinkMap();
lm != (struct link_map *) 0; lm = lm->l_next)
{
ElfW(Ehdr) * e;
ElfW(Phdr) * p;
unsigned long offset;
char * start;
register int i;
e = (ElfW(Ehdr) *) lm->l_addr;
p = ((ElfW(Phdr) *)(((char *)(e)) + e->e_phoff));
offset = ((unsigned long)(lm->l_addr));
for( i = 0; i < (int)(e->e_phnum); ((i++),(p++)) ) {
switch( p->p_type ) {
case PT_LOAD:
{
if( !(p->p_flags & PF_W) ) break;
start = ((char *)(p->p_vaddr)) + offset;
GC_add_roots_inner(start, start + p->p_memsz, TRUE);
}
break;
default:
break;
}
}
}
}
#endif /* !USE_PROC_FOR_LIBRARIES */
#endif /* LINUX */
#if defined(USE_PROC_FOR_LIBRARIES) && !defined(LINUX)
#include <sys/procfs.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <elf.h>
#include <errno.h>
#include <signal.h> /* Only for the following test. */
#ifndef _sigargs
# define IRIX6
#endif
extern void * GC_roots_present();
/* The type is a lie, since the real type doesn't make sense here, */
/* and we only test for NULL. */
/* We use /proc to track down all parts of the address space that are */
/* mapped by the process, and throw out regions we know we shouldn't */
/* worry about. This may also work under other SVR4 variants. */
void GC_register_dynamic_libraries()
{
static int fd = -1;
char buf[30];
static prmap_t * addr_map = 0;
static int current_sz = 0; /* Number of records currently in addr_map */
static int needed_sz; /* Required size of addr_map */
register int i;
register long flags;
register ptr_t start;
register ptr_t limit;
ptr_t heap_start = (ptr_t)HEAP_START;
ptr_t heap_end = heap_start;
# ifdef SUNOS5DL
# define MA_PHYS 0
# endif /* SUNOS5DL */
if (fd < 0) {
sprintf(buf, "/proc/%d", getpid());
/* The above generates a lint complaint, since pid_t varies. */
/* It's unclear how to improve this. */
fd = open(buf, O_RDONLY);
if (fd < 0) {
ABORT("/proc open failed");
}
}
if (ioctl(fd, PIOCNMAP, &needed_sz) < 0) {
GC_err_printf2("fd = %d, errno = %d\n", fd, errno);
ABORT("/proc PIOCNMAP ioctl failed");
}
if (needed_sz >= current_sz) {
current_sz = needed_sz * 2 + 1;
/* Expansion, plus room for 0 record */
addr_map = (prmap_t *)GC_scratch_alloc((word)
(current_sz * sizeof(prmap_t)));
}
if (ioctl(fd, PIOCMAP, addr_map) < 0) {
GC_err_printf4("fd = %d, errno = %d, needed_sz = %d, addr_map = 0x%X\n",
fd, errno, needed_sz, addr_map);
ABORT("/proc PIOCMAP ioctl failed");
};
if (GC_n_heap_sects > 0) {
heap_end = GC_heap_sects[GC_n_heap_sects-1].hs_start
+ GC_heap_sects[GC_n_heap_sects-1].hs_bytes;
if (heap_end < GC_scratch_last_end_ptr) heap_end = GC_scratch_last_end_ptr;
}
for (i = 0; i < needed_sz; i++) {
flags = addr_map[i].pr_mflags;
if ((flags & (MA_BREAK | MA_STACK | MA_PHYS
| MA_FETCHOP | MA_NOTCACHED)) != 0) goto irrelevant;
if ((flags & (MA_READ | MA_WRITE)) != (MA_READ | MA_WRITE))
goto irrelevant;
/* The latter test is empirically useless in very old Irix */
/* versions. Other than the */
/* main data and stack segments, everything appears to be */
/* mapped readable, writable, executable, and shared(!!). */
/* This makes no sense to me. - HB */
start = (ptr_t)(addr_map[i].pr_vaddr);
if (GC_roots_present(start)) goto irrelevant;
if (start < heap_end && start >= heap_start)
goto irrelevant;
# ifdef MMAP_STACKS
if (GC_is_thread_stack(start)) goto irrelevant;
# endif /* MMAP_STACKS */
limit = start + addr_map[i].pr_size;
/* The following seemed to be necessary for very old versions */
/* of Irix, but it has been reported to discard relevant */
/* segments under Irix 6.5. */
# ifndef IRIX6
if (addr_map[i].pr_off == 0 && strncmp(start, ELFMAG, 4) == 0) {
/* Discard text segments, i.e. 0-offset mappings against */
/* executable files which appear to have ELF headers. */
caddr_t arg;
int obj;
# define MAP_IRR_SZ 10
static ptr_t map_irr[MAP_IRR_SZ];
/* Known irrelevant map entries */
static int n_irr = 0;
struct stat buf;
register int i;
for (i = 0; i < n_irr; i++) {
if (map_irr[i] == start) goto irrelevant;
}
arg = (caddr_t)start;
obj = ioctl(fd, PIOCOPENM, &arg);
if (obj >= 0) {
fstat(obj, &buf);
close(obj);
if ((buf.st_mode & 0111) != 0) {
if (n_irr < MAP_IRR_SZ) {
map_irr[n_irr++] = start;
}
goto irrelevant;
}
}
}
# endif /* !IRIX6 */
GC_add_roots_inner(start, limit, TRUE);
irrelevant: ;
}
/* Dont keep cached descriptor, for now. Some kernels don't like us */
/* to keep a /proc file descriptor around during kill -9. */
if (close(fd) < 0) ABORT("Couldnt close /proc file");
fd = -1;
}
# endif /* USE_PROC */
# if defined(MSWIN32) || defined(MSWINCE) || defined(CYGWIN32)
# define WIN32_LEAN_AND_MEAN
# define NOSERVICE
# include <windows.h>
# include <stdlib.h>
/* We traverse the entire address space and register all segments */
/* that could possibly have been written to. */
extern GC_bool GC_is_heap_base (ptr_t p);
# ifdef GC_WIN32_THREADS
extern void GC_get_next_stack(char *start, char **lo, char **hi);
void GC_cond_add_roots(char *base, char * limit)
{
char * curr_base = base;
char * next_stack_lo;
char * next_stack_hi;
if (base == limit) return;
for(;;) {
GC_get_next_stack(curr_base, &next_stack_lo, &next_stack_hi);
if (next_stack_lo >= limit) break;
GC_add_roots_inner(curr_base, next_stack_lo, TRUE);
curr_base = next_stack_hi;
}
if (curr_base < limit) GC_add_roots_inner(curr_base, limit, TRUE);
}
# else
void GC_cond_add_roots(char *base, char * limit)
{
char dummy;
char * stack_top
= (char *) ((word)(&dummy) & ~(GC_sysinfo.dwAllocationGranularity-1));
if (base == limit) return;
if (limit > stack_top && base < GC_stackbottom) {
/* Part of the stack; ignore it. */
return;
}
GC_add_roots_inner(base, limit, TRUE);
}
# endif
# if defined(MSWINCE) || defined(CYGWIN32)
/* Do we need to separately register the main static data segment? */
GC_bool GC_register_main_static_data()
{
return FALSE;
}
# else /* win32 */
extern GC_bool GC_no_win32_dlls;
GC_bool GC_register_main_static_data()
{
return GC_no_win32_dlls;
}
# endif /* win32 */
# define HAVE_REGISTER_MAIN_STATIC_DATA
/* The frame buffer testing code is dead in this version. */
/* We leave it here temporarily in case the switch to just */
/* testing for MEM_IMAGE sections causes un expected */
/* problems. */
GC_bool GC_warn_fb = TRUE; /* Warn about traced likely */
/* graphics memory. */
GC_bool GC_disallow_ignore_fb = FALSE;
int GC_ignore_fb_mb; /* Ignore mappings bigger than the */
/* specified number of MB. */
GC_bool GC_ignore_fb = FALSE; /* Enable frame buffer */
/* checking. */
/* Issue warning if tracing apparent framebuffer. */
/* This limits us to one warning, and it's a back door to */
/* disable that. */
/* Should [start, start+len) be treated as a frame buffer */
/* and ignored? */
/* Unfortunately, we currently are not quite sure how to tell */
/* this automatically, and rely largely on user input. */
/* We expect that any mapping with type MEM_MAPPED (which */
/* apparently excludes library data sections) can be safely */
/* ignored. But we're too chicken to do that in this */
/* version. */
/* Based on a very limited sample, it appears that: */
/* - Frame buffer mappings appear as mappings of large */
/* length, usually a bit less than a power of two. */
/* - The definition of "a bit less" in the above cannot */
/* be made more precise. */
/* - Have a starting address at best 64K aligned. */
/* - Have type == MEM_MAPPED. */
static GC_bool is_frame_buffer(ptr_t start, size_t len, DWORD tp)
{
static GC_bool initialized = FALSE;
# define MB (1024*1024)
# define DEFAULT_FB_MB 15
# define MIN_FB_MB 3
if (GC_disallow_ignore_fb || tp != MEM_MAPPED) return FALSE;
if (!initialized) {
char * ignore_fb_string = GETENV("GC_IGNORE_FB");
if (0 != ignore_fb_string) {
while (*ignore_fb_string == ' ' || *ignore_fb_string == '\t')
++ignore_fb_string;
if (*ignore_fb_string == '\0') {
GC_ignore_fb_mb = DEFAULT_FB_MB;
} else {
GC_ignore_fb_mb = atoi(ignore_fb_string);
if (GC_ignore_fb_mb < MIN_FB_MB) {
WARN("Bad GC_IGNORE_FB value. Using %ld\n", DEFAULT_FB_MB);
GC_ignore_fb_mb = DEFAULT_FB_MB;
}
}
GC_ignore_fb = TRUE;
} else {
GC_ignore_fb_mb = DEFAULT_FB_MB; /* For warning */
}
initialized = TRUE;
}
if (len >= ((size_t)GC_ignore_fb_mb << 20)) {
if (GC_ignore_fb) {
return TRUE;
} else {
if (GC_warn_fb) {
WARN("Possible frame buffer mapping at 0x%lx: \n"
"\tConsider setting GC_IGNORE_FB to improve performance.\n",
start);
GC_warn_fb = FALSE;
}
return FALSE;
}
} else {
return FALSE;
}
}
# ifdef DEBUG_VIRTUALQUERY
void GC_dump_meminfo(MEMORY_BASIC_INFORMATION *buf)
{
GC_printf4("BaseAddress = %lx, AllocationBase = %lx, RegionSize = %lx(%lu)\n",
buf -> BaseAddress, buf -> AllocationBase, buf -> RegionSize,
buf -> RegionSize);
GC_printf4("\tAllocationProtect = %lx, State = %lx, Protect = %lx, "
"Type = %lx\n",
buf -> AllocationProtect, buf -> State, buf -> Protect,
buf -> Type);
}
# endif /* DEBUG_VIRTUALQUERY */
# ifdef CYGWIN32
# define GC_wnt (TRUE)
# else
extern GC_bool GC_wnt; /* Is Windows NT derivative. */
/* Defined and set in os_dep.c. */
# endif
void GC_register_dynamic_libraries()
{
MEMORY_BASIC_INFORMATION buf;
DWORD result;
DWORD protect;
LPVOID p;
char * base;
char * limit, * new_limit;
# ifdef MSWIN32
if (GC_no_win32_dlls) return;
# endif
base = limit = p = GC_sysinfo.lpMinimumApplicationAddress;
# if defined(MSWINCE) && !defined(_WIN32_WCE_EMULATION)
/* Only the first 32 MB of address space belongs to the current process */
while (p < (LPVOID)0x02000000) {
result = VirtualQuery(p, &buf, sizeof(buf));
if (result == 0) {
/* Page is free; advance to the next possible allocation base */
new_limit = (char *)
(((DWORD) p + GC_sysinfo.dwAllocationGranularity)
& ~(GC_sysinfo.dwAllocationGranularity-1));
} else
# else
while (p < GC_sysinfo.lpMaximumApplicationAddress) {
result = VirtualQuery(p, &buf, sizeof(buf));
# endif
{
if (result != sizeof(buf)) {
ABORT("Weird VirtualQuery result");
}
new_limit = (char *)p + buf.RegionSize;
protect = buf.Protect;
if (buf.State == MEM_COMMIT
&& (protect == PAGE_EXECUTE_READWRITE
|| protect == PAGE_READWRITE)
&& !GC_is_heap_base(buf.AllocationBase)
/* This used to check for
* !is_frame_buffer(p, buf.RegionSize, buf.Type)
* instead of just checking for MEM_IMAGE.
* If something breaks, change it back. */
/* There is some evidence that we cannot always
* ignore MEM_PRIVATE sections under Windows ME
* and predecessors. Hence we now also check for
* that case. */
&& (buf.Type == MEM_IMAGE ||
!GC_wnt && buf.Type == MEM_PRIVATE)) {
# ifdef DEBUG_VIRTUALQUERY
GC_dump_meminfo(&buf);
# endif
if ((char *)p != limit) {
GC_cond_add_roots(base, limit);
base = p;
}
limit = new_limit;
}