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
|
/* GDB routines for manipulating objfiles.
Copyright 1992 Free Software Foundation, Inc.
Contributed by Cygnus Support, using pieces from other GDB modules.
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
/* This file contains support routines for creating, manipulating, and
destroying objfile structures. */
#include "defs.h"
#include "bfd.h" /* Binary File Description */
#include "symtab.h"
#include "symfile.h"
#include "objfiles.h"
#include "gdb-stabs.h"
#include "target.h"
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <obstack.h>
/* Prototypes for local functions */
#if !defined(NO_MMALLOC) && defined(HAVE_MMAP)
static int
open_existing_mapped_file PARAMS ((char *, long, int));
static int
open_mapped_file PARAMS ((char *filename, long mtime, int mapped));
static CORE_ADDR
map_to_address PARAMS ((void));
#endif /* !defined(NO_MMALLOC) && defined(HAVE_MMAP) */
/* Message to be printed before the error message, when an error occurs. */
extern char *error_pre_print;
/* Externally visible variables that are owned by this module.
See declarations in objfile.h for more info. */
struct objfile *object_files; /* Linked list of all objfiles */
struct objfile *current_objfile; /* For symbol file being read in */
struct objfile *symfile_objfile; /* Main symbol table loaded from */
int mapped_symbol_files; /* Try to use mapped symbol files */
/* Locate all mappable sections of a BFD file.
objfile_p_char is a char * to get it through
bfd_map_over_sections; we cast it back to its proper type. */
static void
add_to_objfile_sections (abfd, asect, objfile_p_char)
bfd *abfd;
sec_ptr asect;
PTR objfile_p_char;
{
struct objfile *objfile = (struct objfile *) objfile_p_char;
struct obj_section section;
flagword aflag;
aflag = bfd_get_section_flags (abfd, asect);
if (!(aflag & SEC_ALLOC))
return;
if (0 == bfd_section_size (abfd, asect))
return;
section.offset = 0;
section.objfile = objfile;
section.the_bfd_section = asect;
section.addr = bfd_section_vma (abfd, asect);
section.endaddr = section.addr + bfd_section_size (abfd, asect);
obstack_grow (&objfile->psymbol_obstack, §ion, sizeof(section));
objfile->sections_end = (struct obj_section *) (((unsigned long) objfile->sections_end) + 1);
}
/* Builds a section table for OBJFILE.
Returns 0 if OK, 1 on error (in which case bfd_error contains the
error). */
int
build_objfile_section_table (objfile)
struct objfile *objfile;
{
/* objfile->sections can be already set when reading a mapped symbol
file. I believe that we do need to rebuild the section table in
this case (we rebuild other things derived from the bfd), but we
can't free the old one (it's in the psymbol_obstack). So we just
waste some memory. */
objfile->sections_end = 0;
bfd_map_over_sections (objfile->obfd, add_to_objfile_sections, (char *)objfile);
objfile->sections = (struct obj_section *)
obstack_finish (&objfile->psymbol_obstack);
objfile->sections_end = objfile->sections + (unsigned long) objfile->sections_end;
return(0);
}
/* Given a pointer to an initialized bfd (ABFD) and a flag that indicates
whether or not an objfile is to be mapped (MAPPED), allocate a new objfile
struct, fill it in as best we can, link it into the list of all known
objfiles, and return a pointer to the new objfile struct. */
struct objfile *
allocate_objfile (abfd, mapped)
bfd *abfd;
int mapped;
{
struct objfile *objfile = NULL;
mapped |= mapped_symbol_files;
#if !defined(NO_MMALLOC) && defined(HAVE_MMAP)
{
/* If we can support mapped symbol files, try to open/reopen the
mapped file that corresponds to the file from which we wish to
read symbols. If the objfile is to be mapped, we must malloc
the structure itself using the mmap version, and arrange that
all memory allocation for the objfile uses the mmap routines.
If we are reusing an existing mapped file, from which we get
our objfile pointer, we have to make sure that we update the
pointers to the alloc/free functions in the obstack, in case
these functions have moved within the current gdb. */
int fd;
fd = open_mapped_file (bfd_get_filename (abfd), bfd_get_mtime (abfd),
mapped);
if (fd >= 0)
{
CORE_ADDR mapto;
PTR md;
if (((mapto = map_to_address ()) == 0) ||
((md = mmalloc_attach (fd, (PTR) mapto)) == NULL))
{
close (fd);
}
else if ((objfile = (struct objfile *) mmalloc_getkey (md, 0)) != NULL)
{
/* Update memory corruption handler function addresses. */
init_malloc (md);
objfile -> md = md;
objfile -> mmfd = fd;
/* Update pointers to functions to *our* copies */
obstack_chunkfun (&objfile -> psymbol_obstack, xmmalloc);
obstack_freefun (&objfile -> psymbol_obstack, mfree);
obstack_chunkfun (&objfile -> symbol_obstack, xmmalloc);
obstack_freefun (&objfile -> symbol_obstack, mfree);
obstack_chunkfun (&objfile -> type_obstack, xmmalloc);
obstack_freefun (&objfile -> type_obstack, mfree);
/* If already in objfile list, unlink it. */
unlink_objfile (objfile);
/* Forget things specific to a particular gdb, may have changed. */
objfile -> sf = NULL;
}
else
{
/* Set up to detect internal memory corruption. MUST be
done before the first malloc. See comments in
init_malloc() and mmcheck(). */
init_malloc (md);
objfile = (struct objfile *)
xmmalloc (md, sizeof (struct objfile));
memset (objfile, 0, sizeof (struct objfile));
objfile -> md = md;
objfile -> mmfd = fd;
objfile -> flags |= OBJF_MAPPED;
mmalloc_setkey (objfile -> md, 0, objfile);
obstack_specify_allocation_with_arg (&objfile -> psymbol_obstack,
0, 0, xmmalloc, mfree,
objfile -> md);
obstack_specify_allocation_with_arg (&objfile -> symbol_obstack,
0, 0, xmmalloc, mfree,
objfile -> md);
obstack_specify_allocation_with_arg (&objfile -> type_obstack,
0, 0, xmmalloc, mfree,
objfile -> md);
}
}
if (mapped && (objfile == NULL))
{
warning ("symbol table for '%s' will not be mapped",
bfd_get_filename (abfd));
}
}
#else /* defined(NO_MMALLOC) || !defined(HAVE_MMAP) */
if (mapped)
{
warning ("this version of gdb does not support mapped symbol tables.");
/* Turn off the global flag so we don't try to do mapped symbol tables
any more, which shuts up gdb unless the user specifically gives the
"mapped" keyword again. */
mapped_symbol_files = 0;
}
#endif /* !defined(NO_MMALLOC) && defined(HAVE_MMAP) */
/* If we don't support mapped symbol files, didn't ask for the file to be
mapped, or failed to open the mapped file for some reason, then revert
back to an unmapped objfile. */
if (objfile == NULL)
{
objfile = (struct objfile *) xmalloc (sizeof (struct objfile));
memset (objfile, 0, sizeof (struct objfile));
objfile -> md = NULL;
obstack_specify_allocation (&objfile -> psymbol_obstack, 0, 0, xmalloc,
free);
obstack_specify_allocation (&objfile -> symbol_obstack, 0, 0, xmalloc,
free);
obstack_specify_allocation (&objfile -> type_obstack, 0, 0, xmalloc,
free);
}
/* Update the per-objfile information that comes from the bfd, ensuring
that any data that is reference is saved in the per-objfile data
region. */
objfile -> obfd = abfd;
if (objfile -> name != NULL)
{
mfree (objfile -> md, objfile -> name);
}
objfile -> name = mstrsave (objfile -> md, bfd_get_filename (abfd));
objfile -> mtime = bfd_get_mtime (abfd);
/* Build section table. */
if (build_objfile_section_table (objfile))
{
error ("Can't find the file sections in `%s': %s",
objfile -> name, bfd_errmsg (bfd_get_error ()));
}
/* Push this file onto the head of the linked list of other such files. */
objfile -> next = object_files;
object_files = objfile;
return (objfile);
}
/* Unlink OBJFILE from the list of known objfiles, if it is found in the
list.
It is not a bug, or error, to call this function if OBJFILE is not known
to be in the current list. This is done in the case of mapped objfiles,
for example, just to ensure that the mapped objfile doesn't appear twice
in the list. Since the list is threaded, linking in a mapped objfile
twice would create a circular list.
If OBJFILE turns out to be in the list, we zap it's NEXT pointer after
unlinking it, just to ensure that we have completely severed any linkages
between the OBJFILE and the list. */
void
unlink_objfile (objfile)
struct objfile *objfile;
{
struct objfile** objpp;
for (objpp = &object_files; *objpp != NULL; objpp = &((*objpp) -> next))
{
if (*objpp == objfile)
{
*objpp = (*objpp) -> next;
objfile -> next = NULL;
break;
}
}
}
/* Destroy an objfile and all the symtabs and psymtabs under it. Note
that as much as possible is allocated on the symbol_obstack and
psymbol_obstack, so that the memory can be efficiently freed.
Things which we do NOT free because they are not in malloc'd memory
or not in memory specific to the objfile include:
objfile -> sf
FIXME: If the objfile is using reusable symbol information (via mmalloc),
then we need to take into account the fact that more than one process
may be using the symbol information at the same time (when mmalloc is
extended to support cooperative locking). When more than one process
is using the mapped symbol info, we need to be more careful about when
we free objects in the reusable area. */
void
free_objfile (objfile)
struct objfile *objfile;
{
/* First do any symbol file specific actions required when we are
finished with a particular symbol file. Note that if the objfile
is using reusable symbol information (via mmalloc) then each of
these routines is responsible for doing the correct thing, either
freeing things which are valid only during this particular gdb
execution, or leaving them to be reused during the next one. */
if (objfile -> sf != NULL)
{
(*objfile -> sf -> sym_finish) (objfile);
}
/* We always close the bfd. */
if (objfile -> obfd != NULL)
{
char *name = bfd_get_filename (objfile->obfd);
bfd_close (objfile -> obfd);
free (name);
}
/* Remove it from the chain of all objfiles. */
unlink_objfile (objfile);
/* Before the symbol table code was redone to make it easier to
selectively load and remove information particular to a specific
linkage unit, gdb used to do these things whenever the monolithic
symbol table was blown away. How much still needs to be done
is unknown, but we play it safe for now and keep each action until
it is shown to be no longer needed. */
#if defined (CLEAR_SOLIB)
CLEAR_SOLIB ();
/* CLEAR_SOLIB closes the bfd's for any shared libraries. But
the to_sections for a core file might refer to those bfd's. So
detach any core file. */
{
struct target_ops *t = find_core_target ();
if (t != NULL)
(t->to_detach) (NULL, 0);
}
#endif
/* I *think* all our callers call clear_symtab_users. If so, no need
to call this here. */
clear_pc_function_cache ();
/* The last thing we do is free the objfile struct itself for the
non-reusable case, or detach from the mapped file for the reusable
case. Note that the mmalloc_detach or the mfree is the last thing
we can do with this objfile. */
#if !defined(NO_MMALLOC) && defined(HAVE_MMAP)
if (objfile -> flags & OBJF_MAPPED)
{
/* Remember the fd so we can close it. We can't close it before
doing the detach, and after the detach the objfile is gone. */
int mmfd;
mmfd = objfile -> mmfd;
mmalloc_detach (objfile -> md);
objfile = NULL;
close (mmfd);
}
#endif /* !defined(NO_MMALLOC) && defined(HAVE_MMAP) */
/* If we still have an objfile, then either we don't support reusable
objfiles or this one was not reusable. So free it normally. */
if (objfile != NULL)
{
if (objfile -> name != NULL)
{
mfree (objfile -> md, objfile -> name);
}
if (objfile->global_psymbols.list)
mfree (objfile->md, objfile->global_psymbols.list);
if (objfile->static_psymbols.list)
mfree (objfile->md, objfile->static_psymbols.list);
/* Free the obstacks for non-reusable objfiles */
obstack_free (&objfile -> psymbol_obstack, 0);
obstack_free (&objfile -> symbol_obstack, 0);
obstack_free (&objfile -> type_obstack, 0);
mfree (objfile -> md, objfile);
objfile = NULL;
}
}
/* Free all the object files at once and clean up their users. */
void
free_all_objfiles ()
{
struct objfile *objfile, *temp;
ALL_OBJFILES_SAFE (objfile, temp)
{
free_objfile (objfile);
}
clear_symtab_users ();
}
/* Relocate OBJFILE to NEW_OFFSETS. There should be OBJFILE->NUM_SECTIONS
entries in new_offsets. */
void
objfile_relocate (objfile, new_offsets)
struct objfile *objfile;
struct section_offsets *new_offsets;
{
struct section_offsets *delta = (struct section_offsets *) alloca
(sizeof (struct section_offsets)
+ objfile->num_sections * sizeof (delta->offsets));
{
int i;
int something_changed = 0;
for (i = 0; i < objfile->num_sections; ++i)
{
ANOFFSET (delta, i) =
ANOFFSET (new_offsets, i) - ANOFFSET (objfile->section_offsets, i);
if (ANOFFSET (delta, i) != 0)
something_changed = 1;
}
if (!something_changed)
return;
}
/* OK, get all the symtabs. */
{
struct symtab *s;
ALL_OBJFILE_SYMTABS (objfile, s)
{
struct linetable *l;
struct blockvector *bv;
int i;
/* First the line table. */
l = LINETABLE (s);
if (l)
{
for (i = 0; i < l->nitems; ++i)
l->item[i].pc += ANOFFSET (delta, s->block_line_section);
}
/* Don't relocate a shared blockvector more than once. */
if (!s->primary)
continue;
bv = BLOCKVECTOR (s);
for (i = 0; i < BLOCKVECTOR_NBLOCKS (bv); ++i)
{
struct block *b;
int j;
b = BLOCKVECTOR_BLOCK (bv, i);
BLOCK_START (b) += ANOFFSET (delta, s->block_line_section);
BLOCK_END (b) += ANOFFSET (delta, s->block_line_section);
for (j = 0; j < BLOCK_NSYMS (b); ++j)
{
struct symbol *sym = BLOCK_SYM (b, j);
/* The RS6000 code from which this was taken skipped
any symbols in STRUCT_NAMESPACE or UNDEF_NAMESPACE.
But I'm leaving out that test, on the theory that
they can't possibly pass the tests below. */
if ((SYMBOL_CLASS (sym) == LOC_LABEL
|| SYMBOL_CLASS (sym) == LOC_STATIC)
&& SYMBOL_SECTION (sym) >= 0)
{
SYMBOL_VALUE_ADDRESS (sym) +=
ANOFFSET (delta, SYMBOL_SECTION (sym));
}
#ifdef MIPS_EFI_SYMBOL_NAME
/* Relocate Extra Function Info for ecoff. */
else
if (SYMBOL_CLASS (sym) == LOC_CONST
&& SYMBOL_NAMESPACE (sym) == LABEL_NAMESPACE
&& STRCMP (SYMBOL_NAME (sym), MIPS_EFI_SYMBOL_NAME) == 0)
ecoff_relocate_efi (sym, ANOFFSET (delta, s->block_line_section));
#endif
}
}
}
}
{
struct partial_symtab *p;
ALL_OBJFILE_PSYMTABS (objfile, p)
{
/* FIXME: specific to symbol readers which use gdb-stabs.h.
We can only get away with it since objfile_relocate is only
used on XCOFF, which lacks psymtabs, and for gdb-stabs.h
targets. */
p->textlow += ANOFFSET (delta, SECT_OFF_TEXT);
p->texthigh += ANOFFSET (delta, SECT_OFF_TEXT);
}
}
{
struct partial_symbol *psym;
for (psym = objfile->global_psymbols.list;
psym < objfile->global_psymbols.next;
psym++)
if (SYMBOL_SECTION (psym) >= 0)
SYMBOL_VALUE_ADDRESS (psym) += ANOFFSET (delta, SYMBOL_SECTION (psym));
for (psym = objfile->static_psymbols.list;
psym < objfile->static_psymbols.next;
psym++)
if (SYMBOL_SECTION (psym) >= 0)
SYMBOL_VALUE_ADDRESS (psym) += ANOFFSET (delta, SYMBOL_SECTION (psym));
}
{
struct minimal_symbol *msym;
ALL_OBJFILE_MSYMBOLS (objfile, msym)
if (SYMBOL_SECTION (msym) >= 0)
SYMBOL_VALUE_ADDRESS (msym) += ANOFFSET (delta, SYMBOL_SECTION (msym));
}
{
int i;
for (i = 0; i < objfile->num_sections; ++i)
ANOFFSET (objfile->section_offsets, i) = ANOFFSET (new_offsets, i);
}
{
struct obj_section *s;
bfd *abfd;
abfd = symfile_objfile->obfd;
for (s = symfile_objfile->sections;
s < symfile_objfile->sections_end; ++s)
{
flagword flags;
flags = bfd_get_section_flags (abfd, s->the_bfd_section);
if (flags & SEC_CODE)
{
s->addr += ANOFFSET (delta, SECT_OFF_TEXT);
s->endaddr += ANOFFSET (delta, SECT_OFF_TEXT);
}
else if (flags & (SEC_DATA | SEC_LOAD))
{
s->addr += ANOFFSET (delta, SECT_OFF_DATA);
s->endaddr += ANOFFSET (delta, SECT_OFF_DATA);
}
else if (flags & SEC_ALLOC)
{
s->addr += ANOFFSET (delta, SECT_OFF_BSS);
s->endaddr += ANOFFSET (delta, SECT_OFF_BSS);
}
}
}
}
/* Many places in gdb want to test just to see if we have any partial
symbols available. This function returns zero if none are currently
available, nonzero otherwise. */
int
have_partial_symbols ()
{
struct objfile *ofp;
ALL_OBJFILES (ofp)
{
if (ofp -> psymtabs != NULL)
{
return 1;
}
}
return 0;
}
/* Many places in gdb want to test just to see if we have any full
symbols available. This function returns zero if none are currently
available, nonzero otherwise. */
int
have_full_symbols ()
{
struct objfile *ofp;
ALL_OBJFILES (ofp)
{
if (ofp -> symtabs != NULL)
{
return 1;
}
}
return 0;
}
/* Many places in gdb want to test just to see if we have any minimal
symbols available. This function returns zero if none are currently
available, nonzero otherwise. */
int
have_minimal_symbols ()
{
struct objfile *ofp;
ALL_OBJFILES (ofp)
{
if (ofp -> msymbols != NULL)
{
return 1;
}
}
return 0;
}
#if !defined(NO_MMALLOC) && defined(HAVE_MMAP)
/* Given the name of a mapped symbol file in SYMSFILENAME, and the timestamp
of the corresponding symbol file in MTIME, try to open an existing file
with the name SYMSFILENAME and verify it is more recent than the base
file by checking it's timestamp against MTIME.
If SYMSFILENAME does not exist (or can't be stat'd), simply returns -1.
If SYMSFILENAME does exist, but is out of date, we check to see if the
user has specified creation of a mapped file. If so, we don't issue
any warning message because we will be creating a new mapped file anyway,
overwriting the old one. If not, then we issue a warning message so that
the user will know why we aren't using this existing mapped symbol file.
In either case, we return -1.
If SYMSFILENAME does exist and is not out of date, but can't be opened for
some reason, then prints an appropriate system error message and returns -1.
Otherwise, returns the open file descriptor. */
static int
open_existing_mapped_file (symsfilename, mtime, mapped)
char *symsfilename;
long mtime;
int mapped;
{
int fd = -1;
struct stat sbuf;
if (stat (symsfilename, &sbuf) == 0)
{
if (sbuf.st_mtime < mtime)
{
if (!mapped)
{
warning ("mapped symbol file `%s' is out of date, ignored it",
symsfilename);
}
}
else if ((fd = open (symsfilename, O_RDWR)) < 0)
{
if (error_pre_print)
{
printf_unfiltered (error_pre_print);
}
print_sys_errmsg (symsfilename, errno);
}
}
return (fd);
}
/* Look for a mapped symbol file that corresponds to FILENAME and is more
recent than MTIME. If MAPPED is nonzero, the user has asked that gdb
use a mapped symbol file for this file, so create a new one if one does
not currently exist.
If found, then return an open file descriptor for the file, otherwise
return -1.
This routine is responsible for implementing the policy that generates
the name of the mapped symbol file from the name of a file containing
symbols that gdb would like to read. Currently this policy is to append
".syms" to the name of the file.
This routine is also responsible for implementing the policy that
determines where the mapped symbol file is found (the search path).
This policy is that when reading an existing mapped file, a file of
the correct name in the current directory takes precedence over a
file of the correct name in the same directory as the symbol file.
When creating a new mapped file, it is always created in the current
directory. This helps to minimize the chances of a user unknowingly
creating big mapped files in places like /bin and /usr/local/bin, and
allows a local copy to override a manually installed global copy (in
/bin for example). */
static int
open_mapped_file (filename, mtime, mapped)
char *filename;
long mtime;
int mapped;
{
int fd;
char *symsfilename;
/* First try to open an existing file in the current directory, and
then try the directory where the symbol file is located. */
symsfilename = concat ("./", basename (filename), ".syms", (char *) NULL);
if ((fd = open_existing_mapped_file (symsfilename, mtime, mapped)) < 0)
{
free (symsfilename);
symsfilename = concat (filename, ".syms", (char *) NULL);
fd = open_existing_mapped_file (symsfilename, mtime, mapped);
}
/* If we don't have an open file by now, then either the file does not
already exist, or the base file has changed since it was created. In
either case, if the user has specified use of a mapped file, then
create a new mapped file, truncating any existing one. If we can't
create one, print a system error message saying why we can't.
By default the file is rw for everyone, with the user's umask taking
care of turning off the permissions the user wants off. */
if ((fd < 0) && mapped)
{
free (symsfilename);
symsfilename = concat ("./", basename (filename), ".syms",
(char *) NULL);
if ((fd = open (symsfilename, O_RDWR | O_CREAT | O_TRUNC, 0666)) < 0)
{
if (error_pre_print)
{
printf_unfiltered (error_pre_print);
}
print_sys_errmsg (symsfilename, errno);
}
}
free (symsfilename);
return (fd);
}
/* Return the base address at which we would like the next objfile's
mapped data to start.
For now, we use the kludge that the configuration specifies a base
address to which it is safe to map the first mmalloc heap, and an
increment to add to this address for each successive heap. There are
a lot of issues to deal with here to make this work reasonably, including:
Avoid memory collisions with existing mapped address spaces
Reclaim address spaces when their mmalloc heaps are unmapped
When mmalloc heaps are shared between processes they have to be
mapped at the same addresses in each
Once created, a mmalloc heap that is to be mapped back in must be
mapped at the original address. I.E. each objfile will expect to
be remapped at it's original address. This becomes a problem if
the desired address is already in use.
etc, etc, etc.
*/
static CORE_ADDR
map_to_address ()
{
#if defined(MMAP_BASE_ADDRESS) && defined (MMAP_INCREMENT)
static CORE_ADDR next = MMAP_BASE_ADDRESS;
CORE_ADDR mapto = next;
next += MMAP_INCREMENT;
return (mapto);
#else
return (0);
#endif
}
#endif /* !defined(NO_MMALLOC) && defined(HAVE_MMAP) */
/* Returns a section whose range includes PC or NULL if none found. */
struct obj_section *
find_pc_section(pc)
CORE_ADDR pc;
{
struct obj_section *s;
struct objfile *objfile;
ALL_OBJFILES (objfile)
for (s = objfile->sections; s < objfile->sections_end; ++s)
if (s->addr <= pc
&& pc < s->endaddr)
return(s);
return(NULL);
}
|