forked from gbenson/binutils-gdb
-
Notifications
You must be signed in to change notification settings - Fork 0
/
Copy pathcoffcode.h
6157 lines (5409 loc) · 176 KB
/
coffcode.h
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
/* Support for the generic parts of most COFF variants, for BFD.
Copyright (C) 1990-2015 Free Software Foundation, Inc.
Written by Cygnus Support.
This file is part of BFD, the Binary File Descriptor library.
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 3 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., 51 Franklin Street - Fifth Floor, Boston,
MA 02110-1301, USA. */
/* Most of this hacked by Steve Chamberlain,
/*
SECTION
coff backends
BFD supports a number of different flavours of coff format.
The major differences between formats are the sizes and
alignments of fields in structures on disk, and the occasional
extra field.
Coff in all its varieties is implemented with a few common
files and a number of implementation specific files. For
example, The 88k bcs coff format is implemented in the file
@file{coff-m88k.c}. This file @code{#include}s
@file{coff/m88k.h} which defines the external structure of the
coff format for the 88k, and @file{coff/internal.h} which
defines the internal structure. @file{coff-m88k.c} also
defines the relocations used by the 88k format
@xref{Relocations}.
The Intel i960 processor version of coff is implemented in
@file{coff-i960.c}. This file has the same structure as
@file{coff-m88k.c}, except that it includes @file{coff/i960.h}
rather than @file{coff-m88k.h}.
SUBSECTION
Porting to a new version of coff
The recommended method is to select from the existing
implementations the version of coff which is most like the one
you want to use. For example, we'll say that i386 coff is
the one you select, and that your coff flavour is called foo.
Copy @file{i386coff.c} to @file{foocoff.c}, copy
@file{../include/coff/i386.h} to @file{../include/coff/foo.h},
and add the lines to @file{targets.c} and @file{Makefile.in}
so that your new back end is used. Alter the shapes of the
structures in @file{../include/coff/foo.h} so that they match
what you need. You will probably also have to add
@code{#ifdef}s to the code in @file{coff/internal.h} and
@file{coffcode.h} if your version of coff is too wild.
You can verify that your new BFD backend works quite simply by
building @file{objdump} from the @file{binutils} directory,
and making sure that its version of what's going on and your
host system's idea (assuming it has the pretty standard coff
dump utility, usually called @code{att-dump} or just
@code{dump}) are the same. Then clean up your code, and send
what you've done to Cygnus. Then your stuff will be in the
next release, and you won't have to keep integrating it.
SUBSECTION
How the coff backend works
SUBSUBSECTION
File layout
The Coff backend is split into generic routines that are
applicable to any Coff target and routines that are specific
to a particular target. The target-specific routines are
further split into ones which are basically the same for all
Coff targets except that they use the external symbol format
or use different values for certain constants.
The generic routines are in @file{coffgen.c}. These routines
work for any Coff target. They use some hooks into the target
specific code; the hooks are in a @code{bfd_coff_backend_data}
structure, one of which exists for each target.
The essentially similar target-specific routines are in
@file{coffcode.h}. This header file includes executable C code.
The various Coff targets first include the appropriate Coff
header file, make any special defines that are needed, and
then include @file{coffcode.h}.
Some of the Coff targets then also have additional routines in
the target source file itself.
For example, @file{coff-i960.c} includes
@file{coff/internal.h} and @file{coff/i960.h}. It then
defines a few constants, such as @code{I960}, and includes
@file{coffcode.h}. Since the i960 has complex relocation
types, @file{coff-i960.c} also includes some code to
manipulate the i960 relocs. This code is not in
@file{coffcode.h} because it would not be used by any other
target.
SUBSUBSECTION
Coff long section names
In the standard Coff object format, section names are limited to
the eight bytes available in the @code{s_name} field of the
@code{SCNHDR} section header structure. The format requires the
field to be NUL-padded, but not necessarily NUL-terminated, so
the longest section names permitted are a full eight characters.
The Microsoft PE variants of the Coff object file format add
an extension to support the use of long section names. This
extension is defined in section 4 of the Microsoft PE/COFF
specification (rev 8.1). If a section name is too long to fit
into the section header's @code{s_name} field, it is instead
placed into the string table, and the @code{s_name} field is
filled with a slash ("/") followed by the ASCII decimal
representation of the offset of the full name relative to the
string table base.
Note that this implies that the extension can only be used in object
files, as executables do not contain a string table. The standard
specifies that long section names from objects emitted into executable
images are to be truncated.
However, as a GNU extension, BFD can generate executable images
that contain a string table and long section names. This
would appear to be technically valid, as the standard only says
that Coff debugging information is deprecated, not forbidden,
and in practice it works, although some tools that parse PE files
expecting the MS standard format may become confused; @file{PEview} is
one known example.
The functionality is supported in BFD by code implemented under
the control of the macro @code{COFF_LONG_SECTION_NAMES}. If not
defined, the format does not support long section names in any way.
If defined, it is used to initialise a flag,
@code{_bfd_coff_long_section_names}, and a hook function pointer,
@code{_bfd_coff_set_long_section_names}, in the Coff backend data
structure. The flag controls the generation of long section names
in output BFDs at runtime; if it is false, as it will be by default
when generating an executable image, long section names are truncated;
if true, the long section names extension is employed. The hook
points to a function that allows the value of the flag to be altered
at runtime, on formats that support long section names at all; on
other formats it points to a stub that returns an error indication.
With input BFDs, the flag is set according to whether any long section
names are detected while reading the section headers. For a completely
new BFD, the flag is set to the default for the target format. This
information can be used by a client of the BFD library when deciding
what output format to generate, and means that a BFD that is opened
for read and subsequently converted to a writeable BFD and modified
in-place will retain whatever format it had on input.
If @code{COFF_LONG_SECTION_NAMES} is simply defined (blank), or is
defined to the value "1", then long section names are enabled by
default; if it is defined to the value zero, they are disabled by
default (but still accepted in input BFDs). The header @file{coffcode.h}
defines a macro, @code{COFF_DEFAULT_LONG_SECTION_NAMES}, which is
used in the backends to initialise the backend data structure fields
appropriately; see the comments for further detail.
SUBSUBSECTION
Bit twiddling
Each flavour of coff supported in BFD has its own header file
describing the external layout of the structures. There is also
an internal description of the coff layout, in
@file{coff/internal.h}. A major function of the
coff backend is swapping the bytes and twiddling the bits to
translate the external form of the structures into the normal
internal form. This is all performed in the
@code{bfd_swap}_@i{thing}_@i{direction} routines. Some
elements are different sizes between different versions of
coff; it is the duty of the coff version specific include file
to override the definitions of various packing routines in
@file{coffcode.h}. E.g., the size of line number entry in coff is
sometimes 16 bits, and sometimes 32 bits. @code{#define}ing
@code{PUT_LNSZ_LNNO} and @code{GET_LNSZ_LNNO} will select the
correct one. No doubt, some day someone will find a version of
coff which has a varying field size not catered to at the
moment. To port BFD, that person will have to add more @code{#defines}.
Three of the bit twiddling routines are exported to
@code{gdb}; @code{coff_swap_aux_in}, @code{coff_swap_sym_in}
and @code{coff_swap_lineno_in}. @code{GDB} reads the symbol
table on its own, but uses BFD to fix things up. More of the
bit twiddlers are exported for @code{gas};
@code{coff_swap_aux_out}, @code{coff_swap_sym_out},
@code{coff_swap_lineno_out}, @code{coff_swap_reloc_out},
@code{coff_swap_filehdr_out}, @code{coff_swap_aouthdr_out},
@code{coff_swap_scnhdr_out}. @code{Gas} currently keeps track
of all the symbol table and reloc drudgery itself, thereby
saving the internal BFD overhead, but uses BFD to swap things
on the way out, making cross ports much safer. Doing so also
allows BFD (and thus the linker) to use the same header files
as @code{gas}, which makes one avenue to disaster disappear.
SUBSUBSECTION
Symbol reading
The simple canonical form for symbols used by BFD is not rich
enough to keep all the information available in a coff symbol
table. The back end gets around this problem by keeping the original
symbol table around, "behind the scenes".
When a symbol table is requested (through a call to
@code{bfd_canonicalize_symtab}), a request gets through to
@code{coff_get_normalized_symtab}. This reads the symbol table from
the coff file and swaps all the structures inside into the
internal form. It also fixes up all the pointers in the table
(represented in the file by offsets from the first symbol in
the table) into physical pointers to elements in the new
internal table. This involves some work since the meanings of
fields change depending upon context: a field that is a
pointer to another structure in the symbol table at one moment
may be the size in bytes of a structure at the next. Another
pass is made over the table. All symbols which mark file names
(<<C_FILE>> symbols) are modified so that the internal
string points to the value in the auxent (the real filename)
rather than the normal text associated with the symbol
(@code{".file"}).
At this time the symbol names are moved around. Coff stores
all symbols less than nine characters long physically
within the symbol table; longer strings are kept at the end of
the file in the string table. This pass moves all strings
into memory and replaces them with pointers to the strings.
The symbol table is massaged once again, this time to create
the canonical table used by the BFD application. Each symbol
is inspected in turn, and a decision made (using the
@code{sclass} field) about the various flags to set in the
@code{asymbol}. @xref{Symbols}. The generated canonical table
shares strings with the hidden internal symbol table.
Any linenumbers are read from the coff file too, and attached
to the symbols which own the functions the linenumbers belong to.
SUBSUBSECTION
Symbol writing
Writing a symbol to a coff file which didn't come from a coff
file will lose any debugging information. The @code{asymbol}
structure remembers the BFD from which the symbol was taken, and on
output the back end makes sure that the same destination target as
source target is present.
When the symbols have come from a coff file then all the
debugging information is preserved.
Symbol tables are provided for writing to the back end in a
vector of pointers to pointers. This allows applications like
the linker to accumulate and output large symbol tables
without having to do too much byte copying.
This function runs through the provided symbol table and
patches each symbol marked as a file place holder
(@code{C_FILE}) to point to the next file place holder in the
list. It also marks each @code{offset} field in the list with
the offset from the first symbol of the current symbol.
Another function of this procedure is to turn the canonical
value form of BFD into the form used by coff. Internally, BFD
expects symbol values to be offsets from a section base; so a
symbol physically at 0x120, but in a section starting at
0x100, would have the value 0x20. Coff expects symbols to
contain their final value, so symbols have their values
changed at this point to reflect their sum with their owning
section. This transformation uses the
<<output_section>> field of the @code{asymbol}'s
@code{asection} @xref{Sections}.
o <<coff_mangle_symbols>>
This routine runs though the provided symbol table and uses
the offsets generated by the previous pass and the pointers
generated when the symbol table was read in to create the
structured hierarchy required by coff. It changes each pointer
to a symbol into the index into the symbol table of the asymbol.
o <<coff_write_symbols>>
This routine runs through the symbol table and patches up the
symbols from their internal form into the coff way, calls the
bit twiddlers, and writes out the table to the file.
*/
/*
INTERNAL_DEFINITION
coff_symbol_type
DESCRIPTION
The hidden information for an <<asymbol>> is described in a
<<combined_entry_type>>:
CODE_FRAGMENT
.
.typedef struct coff_ptr_struct
.{
. {* Remembers the offset from the first symbol in the file for
. this symbol. Generated by coff_renumber_symbols. *}
. unsigned int offset;
.
. {* Should the value of this symbol be renumbered. Used for
. XCOFF C_BSTAT symbols. Set by coff_slurp_symbol_table. *}
. unsigned int fix_value : 1;
.
. {* Should the tag field of this symbol be renumbered.
. Created by coff_pointerize_aux. *}
. unsigned int fix_tag : 1;
.
. {* Should the endidx field of this symbol be renumbered.
. Created by coff_pointerize_aux. *}
. unsigned int fix_end : 1;
.
. {* Should the x_csect.x_scnlen field be renumbered.
. Created by coff_pointerize_aux. *}
. unsigned int fix_scnlen : 1;
.
. {* Fix up an XCOFF C_BINCL/C_EINCL symbol. The value is the
. index into the line number entries. Set by coff_slurp_symbol_table. *}
. unsigned int fix_line : 1;
.
. {* The container for the symbol structure as read and translated
. from the file. *}
. union
. {
. union internal_auxent auxent;
. struct internal_syment syment;
. } u;
.
. {* Selector for the union above. *}
. bfd_boolean is_sym;
.} combined_entry_type;
.
.
.{* Each canonical asymbol really looks like this: *}
.
.typedef struct coff_symbol_struct
.{
. {* The actual symbol which the rest of BFD works with *}
. asymbol symbol;
.
. {* A pointer to the hidden information for this symbol *}
. combined_entry_type *native;
.
. {* A pointer to the linenumber information for this symbol *}
. struct lineno_cache_entry *lineno;
.
. {* Have the line numbers been relocated yet ? *}
. bfd_boolean done_lineno;
.} coff_symbol_type;
*/
#include "libiberty.h"
#ifdef COFF_WITH_PE
#include "peicode.h"
#else
#include "coffswap.h"
#endif
#define STRING_SIZE_SIZE 4
#define DOT_DEBUG ".debug"
#define DOT_ZDEBUG ".zdebug"
#define GNU_LINKONCE_WI ".gnu.linkonce.wi."
#define GNU_LINKONCE_WT ".gnu.linkonce.wt."
#define DOT_RELOC ".reloc"
#if defined (COFF_LONG_SECTION_NAMES)
/* Needed to expand the inputs to BLANKOR1TOODD. */
#define COFFLONGSECTIONCATHELPER(x,y) x ## y
/* If the input macro Y is blank or '1', return an odd number; if it is
'0', return an even number. Result undefined in all other cases. */
#define BLANKOR1TOODD(y) COFFLONGSECTIONCATHELPER(1,y)
/* Defined to numerical 0 or 1 according to whether generation of long
section names is disabled or enabled by default. */
#define COFF_ENABLE_LONG_SECTION_NAMES (BLANKOR1TOODD(COFF_LONG_SECTION_NAMES) & 1)
/* Where long section names are supported, we allow them to be enabled
and disabled at runtime, so select an appropriate hook function for
_bfd_coff_set_long_section_names. */
#define COFF_LONG_SECTION_NAMES_SETTER bfd_coff_set_long_section_names_allowed
#else /* !defined (COFF_LONG_SECTION_NAMES) */
/* If long section names are not supported, this stub disallows any
attempt to enable them at run-time. */
#define COFF_LONG_SECTION_NAMES_SETTER bfd_coff_set_long_section_names_disallowed
#endif /* defined (COFF_LONG_SECTION_NAMES) */
/* Define a macro that can be used to initialise both the fields relating
to long section names in the backend data struct simultaneously. */
#if COFF_ENABLE_LONG_SECTION_NAMES
#define COFF_DEFAULT_LONG_SECTION_NAMES (TRUE), COFF_LONG_SECTION_NAMES_SETTER
#else /* !COFF_ENABLE_LONG_SECTION_NAMES */
#define COFF_DEFAULT_LONG_SECTION_NAMES (FALSE), COFF_LONG_SECTION_NAMES_SETTER
#endif /* COFF_ENABLE_LONG_SECTION_NAMES */
#if defined (COFF_LONG_SECTION_NAMES)
static bfd_boolean bfd_coff_set_long_section_names_allowed
(bfd *, int);
#else /* !defined (COFF_LONG_SECTION_NAMES) */
static bfd_boolean bfd_coff_set_long_section_names_disallowed
(bfd *, int);
#endif /* defined (COFF_LONG_SECTION_NAMES) */
static long sec_to_styp_flags
(const char *, flagword);
static bfd_boolean styp_to_sec_flags
(bfd *, void *, const char *, asection *, flagword *);
static bfd_boolean coff_bad_format_hook
(bfd *, void *);
static void coff_set_custom_section_alignment
(bfd *, asection *, const struct coff_section_alignment_entry *,
const unsigned int);
static bfd_boolean coff_new_section_hook
(bfd *, asection *);
static bfd_boolean coff_set_arch_mach_hook
(bfd *, void *);
static bfd_boolean coff_write_relocs
(bfd *, int);
static bfd_boolean coff_set_flags
(bfd *, unsigned int *, unsigned short *);
static bfd_boolean coff_set_arch_mach
(bfd *, enum bfd_architecture, unsigned long) ATTRIBUTE_UNUSED;
static bfd_boolean coff_compute_section_file_positions
(bfd *);
static bfd_boolean coff_write_object_contents
(bfd *) ATTRIBUTE_UNUSED;
static bfd_boolean coff_set_section_contents
(bfd *, asection *, const void *, file_ptr, bfd_size_type);
static void * buy_and_read
(bfd *, file_ptr, bfd_size_type);
static bfd_boolean coff_slurp_line_table
(bfd *, asection *);
static bfd_boolean coff_slurp_symbol_table
(bfd *);
static enum coff_symbol_classification coff_classify_symbol
(bfd *, struct internal_syment *);
static bfd_boolean coff_slurp_reloc_table
(bfd *, asection *, asymbol **);
static long coff_canonicalize_reloc
(bfd *, asection *, arelent **, asymbol **);
#ifndef coff_mkobject_hook
static void * coff_mkobject_hook
(bfd *, void *, void *);
#endif
#ifdef COFF_WITH_PE
static flagword handle_COMDAT
(bfd *, flagword, void *, const char *, asection *);
#endif
#ifdef COFF_IMAGE_WITH_PE
static bfd_boolean coff_read_word
(bfd *, unsigned int *);
static unsigned int coff_compute_checksum
(bfd *);
static bfd_boolean coff_apply_checksum
(bfd *);
#endif
#ifdef TICOFF
static bfd_boolean ticoff0_bad_format_hook
(bfd *, void * );
static bfd_boolean ticoff1_bad_format_hook
(bfd *, void * );
#endif
/* void warning(); */
#if defined (COFF_LONG_SECTION_NAMES)
static bfd_boolean
bfd_coff_set_long_section_names_allowed (bfd *abfd, int enable)
{
coff_backend_info (abfd)->_bfd_coff_long_section_names = enable;
return TRUE;
}
#else /* !defined (COFF_LONG_SECTION_NAMES) */
static bfd_boolean
bfd_coff_set_long_section_names_disallowed (bfd *abfd, int enable)
{
(void) abfd;
(void) enable;
return FALSE;
}
#endif /* defined (COFF_LONG_SECTION_NAMES) */
/* Return a word with STYP_* (scnhdr.s_flags) flags set to represent
the incoming SEC_* flags. The inverse of this function is
styp_to_sec_flags(). NOTE: If you add to/change this routine, you
should probably mirror the changes in styp_to_sec_flags(). */
#ifndef COFF_WITH_PE
/* Macros for setting debugging flags. */
#ifdef STYP_DEBUG
#define STYP_XCOFF_DEBUG STYP_DEBUG
#else
#define STYP_XCOFF_DEBUG STYP_INFO
#endif
#ifdef COFF_ALIGN_IN_S_FLAGS
#define STYP_DEBUG_INFO STYP_DSECT
#else
#define STYP_DEBUG_INFO STYP_INFO
#endif
static long
sec_to_styp_flags (const char *sec_name, flagword sec_flags)
{
long styp_flags = 0;
if (!strcmp (sec_name, _TEXT))
{
styp_flags = STYP_TEXT;
}
else if (!strcmp (sec_name, _DATA))
{
styp_flags = STYP_DATA;
}
else if (!strcmp (sec_name, _BSS))
{
styp_flags = STYP_BSS;
#ifdef _COMMENT
}
else if (!strcmp (sec_name, _COMMENT))
{
styp_flags = STYP_INFO;
#endif /* _COMMENT */
#ifdef _LIB
}
else if (!strcmp (sec_name, _LIB))
{
styp_flags = STYP_LIB;
#endif /* _LIB */
#ifdef _LIT
}
else if (!strcmp (sec_name, _LIT))
{
styp_flags = STYP_LIT;
#endif /* _LIT */
}
else if (CONST_STRNEQ (sec_name, DOT_DEBUG)
|| CONST_STRNEQ (sec_name, DOT_ZDEBUG))
{
/* Handle the XCOFF debug section and DWARF2 debug sections. */
if (!sec_name[6])
styp_flags = STYP_XCOFF_DEBUG;
else
styp_flags = STYP_DEBUG_INFO;
}
else if (CONST_STRNEQ (sec_name, ".stab"))
{
styp_flags = STYP_DEBUG_INFO;
}
#ifdef COFF_LONG_SECTION_NAMES
else if (CONST_STRNEQ (sec_name, GNU_LINKONCE_WI)
|| CONST_STRNEQ (sec_name, GNU_LINKONCE_WT))
{
styp_flags = STYP_DEBUG_INFO;
}
#endif
#ifdef RS6000COFF_C
else if (!strcmp (sec_name, _PAD))
{
styp_flags = STYP_PAD;
}
else if (!strcmp (sec_name, _LOADER))
{
styp_flags = STYP_LOADER;
}
else if (!strcmp (sec_name, _EXCEPT))
{
styp_flags = STYP_EXCEPT;
}
else if (!strcmp (sec_name, _TYPCHK))
{
styp_flags = STYP_TYPCHK;
}
else if (sec_flags & SEC_DEBUGGING)
{
int i;
for (i = 0; i < XCOFF_DWSECT_NBR_NAMES; i++)
if (!strcmp (sec_name, xcoff_dwsect_names[i].name))
{
styp_flags = STYP_DWARF | xcoff_dwsect_names[i].flag;
break;
}
}
#endif
/* Try and figure out what it should be */
else if (sec_flags & SEC_CODE)
{
styp_flags = STYP_TEXT;
}
else if (sec_flags & SEC_DATA)
{
styp_flags = STYP_DATA;
}
else if (sec_flags & SEC_READONLY)
{
#ifdef STYP_LIT /* 29k readonly text/data section */
styp_flags = STYP_LIT;
#else
styp_flags = STYP_TEXT;
#endif /* STYP_LIT */
}
else if (sec_flags & SEC_LOAD)
{
styp_flags = STYP_TEXT;
}
else if (sec_flags & SEC_ALLOC)
{
styp_flags = STYP_BSS;
}
#ifdef STYP_CLINK
if (sec_flags & SEC_TIC54X_CLINK)
styp_flags |= STYP_CLINK;
#endif
#ifdef STYP_BLOCK
if (sec_flags & SEC_TIC54X_BLOCK)
styp_flags |= STYP_BLOCK;
#endif
#ifdef STYP_NOLOAD
if ((sec_flags & (SEC_NEVER_LOAD | SEC_COFF_SHARED_LIBRARY)) != 0)
styp_flags |= STYP_NOLOAD;
#endif
return styp_flags;
}
#else /* COFF_WITH_PE */
/* The PE version; see above for the general comments. The non-PE
case seems to be more guessing, and breaks PE format; specifically,
.rdata is readonly, but it sure ain't text. Really, all this
should be set up properly in gas (or whatever assembler is in use),
and honor whatever objcopy/strip, etc. sent us as input. */
static long
sec_to_styp_flags (const char *sec_name, flagword sec_flags)
{
long styp_flags = 0;
bfd_boolean is_dbg = FALSE;
if (CONST_STRNEQ (sec_name, DOT_DEBUG)
|| CONST_STRNEQ (sec_name, DOT_ZDEBUG)
#ifdef COFF_LONG_SECTION_NAMES
|| CONST_STRNEQ (sec_name, GNU_LINKONCE_WI)
|| CONST_STRNEQ (sec_name, GNU_LINKONCE_WT)
#endif
|| CONST_STRNEQ (sec_name, ".stab"))
is_dbg = TRUE;
/* caution: there are at least three groups of symbols that have
very similar bits and meanings: IMAGE_SCN*, SEC_*, and STYP_*.
SEC_* are the BFD internal flags, used for generic BFD
information. STYP_* are the COFF section flags which appear in
COFF files. IMAGE_SCN_* are the PE section flags which appear in
PE files. The STYP_* flags and the IMAGE_SCN_* flags overlap,
but there are more IMAGE_SCN_* flags. */
/* FIXME: There is no gas syntax to specify the debug section flag. */
if (is_dbg)
{
sec_flags &= (SEC_LINK_ONCE | SEC_LINK_DUPLICATES_DISCARD
| SEC_LINK_DUPLICATES_SAME_CONTENTS
| SEC_LINK_DUPLICATES_SAME_SIZE);
sec_flags |= SEC_DEBUGGING | SEC_READONLY;
}
/* skip LOAD */
/* READONLY later */
/* skip RELOC */
if ((sec_flags & SEC_CODE) != 0)
styp_flags |= IMAGE_SCN_CNT_CODE;
if ((sec_flags & (SEC_DATA | SEC_DEBUGGING)) != 0)
styp_flags |= IMAGE_SCN_CNT_INITIALIZED_DATA;
if ((sec_flags & SEC_ALLOC) != 0 && (sec_flags & SEC_LOAD) == 0)
styp_flags |= IMAGE_SCN_CNT_UNINITIALIZED_DATA; /* ==STYP_BSS */
/* skip ROM */
/* skip constRUCTOR */
/* skip CONTENTS */
if ((sec_flags & SEC_IS_COMMON) != 0)
styp_flags |= IMAGE_SCN_LNK_COMDAT;
if ((sec_flags & SEC_DEBUGGING) != 0)
styp_flags |= IMAGE_SCN_MEM_DISCARDABLE;
if ((sec_flags & SEC_EXCLUDE) != 0 && !is_dbg)
styp_flags |= IMAGE_SCN_LNK_REMOVE;
if ((sec_flags & SEC_NEVER_LOAD) != 0 && !is_dbg)
styp_flags |= IMAGE_SCN_LNK_REMOVE;
/* skip IN_MEMORY */
/* skip SORT */
if (sec_flags & SEC_LINK_ONCE)
styp_flags |= IMAGE_SCN_LNK_COMDAT;
if ((sec_flags
& (SEC_LINK_DUPLICATES_DISCARD | SEC_LINK_DUPLICATES_SAME_CONTENTS
| SEC_LINK_DUPLICATES_SAME_SIZE)) != 0)
styp_flags |= IMAGE_SCN_LNK_COMDAT;
/* skip LINKER_CREATED */
if ((sec_flags & SEC_COFF_NOREAD) == 0)
styp_flags |= IMAGE_SCN_MEM_READ; /* Invert NOREAD for read. */
if ((sec_flags & SEC_READONLY) == 0)
styp_flags |= IMAGE_SCN_MEM_WRITE; /* Invert READONLY for write. */
if (sec_flags & SEC_CODE)
styp_flags |= IMAGE_SCN_MEM_EXECUTE; /* CODE->EXECUTE. */
if (sec_flags & SEC_COFF_SHARED)
styp_flags |= IMAGE_SCN_MEM_SHARED; /* Shared remains meaningful. */
return styp_flags;
}
#endif /* COFF_WITH_PE */
/* Return a word with SEC_* flags set to represent the incoming STYP_*
flags (from scnhdr.s_flags). The inverse of this function is
sec_to_styp_flags(). NOTE: If you add to/change this routine, you
should probably mirror the changes in sec_to_styp_flags(). */
#ifndef COFF_WITH_PE
static bfd_boolean
styp_to_sec_flags (bfd *abfd ATTRIBUTE_UNUSED,
void * hdr,
const char *name,
asection *section ATTRIBUTE_UNUSED,
flagword *flags_ptr)
{
struct internal_scnhdr *internal_s = (struct internal_scnhdr *) hdr;
long styp_flags = internal_s->s_flags;
flagword sec_flags = 0;
#ifdef STYP_BLOCK
if (styp_flags & STYP_BLOCK)
sec_flags |= SEC_TIC54X_BLOCK;
#endif
#ifdef STYP_CLINK
if (styp_flags & STYP_CLINK)
sec_flags |= SEC_TIC54X_CLINK;
#endif
#ifdef STYP_NOLOAD
if (styp_flags & STYP_NOLOAD)
sec_flags |= SEC_NEVER_LOAD;
#endif /* STYP_NOLOAD */
/* For 386 COFF, at least, an unloadable text or data section is
actually a shared library section. */
if (styp_flags & STYP_TEXT)
{
if (sec_flags & SEC_NEVER_LOAD)
sec_flags |= SEC_CODE | SEC_COFF_SHARED_LIBRARY;
else
sec_flags |= SEC_CODE | SEC_LOAD | SEC_ALLOC;
}
else if (styp_flags & STYP_DATA)
{
if (sec_flags & SEC_NEVER_LOAD)
sec_flags |= SEC_DATA | SEC_COFF_SHARED_LIBRARY;
else
sec_flags |= SEC_DATA | SEC_LOAD | SEC_ALLOC;
}
else if (styp_flags & STYP_BSS)
{
#ifdef BSS_NOLOAD_IS_SHARED_LIBRARY
if (sec_flags & SEC_NEVER_LOAD)
sec_flags |= SEC_ALLOC | SEC_COFF_SHARED_LIBRARY;
else
#endif
sec_flags |= SEC_ALLOC;
}
else if (styp_flags & STYP_INFO)
{
/* We mark these as SEC_DEBUGGING, but only if COFF_PAGE_SIZE is
defined. coff_compute_section_file_positions uses
COFF_PAGE_SIZE to ensure that the low order bits of the
section VMA and the file offset match. If we don't know
COFF_PAGE_SIZE, we can't ensure the correct correspondence,
and demand page loading of the file will fail. */
#if defined (COFF_PAGE_SIZE) && !defined (COFF_ALIGN_IN_S_FLAGS)
sec_flags |= SEC_DEBUGGING;
#endif
}
else if (styp_flags & STYP_PAD)
sec_flags = 0;
#ifdef RS6000COFF_C
else if (styp_flags & STYP_EXCEPT)
sec_flags |= SEC_LOAD;
else if (styp_flags & STYP_LOADER)
sec_flags |= SEC_LOAD;
else if (styp_flags & STYP_TYPCHK)
sec_flags |= SEC_LOAD;
else if (styp_flags & STYP_DWARF)
sec_flags |= SEC_DEBUGGING;
#endif
else if (strcmp (name, _TEXT) == 0)
{
if (sec_flags & SEC_NEVER_LOAD)
sec_flags |= SEC_CODE | SEC_COFF_SHARED_LIBRARY;
else
sec_flags |= SEC_CODE | SEC_LOAD | SEC_ALLOC;
}
else if (strcmp (name, _DATA) == 0)
{
if (sec_flags & SEC_NEVER_LOAD)
sec_flags |= SEC_DATA | SEC_COFF_SHARED_LIBRARY;
else
sec_flags |= SEC_DATA | SEC_LOAD | SEC_ALLOC;
}
else if (strcmp (name, _BSS) == 0)
{
#ifdef BSS_NOLOAD_IS_SHARED_LIBRARY
if (sec_flags & SEC_NEVER_LOAD)
sec_flags |= SEC_ALLOC | SEC_COFF_SHARED_LIBRARY;
else
#endif
sec_flags |= SEC_ALLOC;
}
else if (CONST_STRNEQ (name, DOT_DEBUG)
|| CONST_STRNEQ (name, DOT_ZDEBUG)
#ifdef _COMMENT
|| strcmp (name, _COMMENT) == 0
#endif
#ifdef COFF_LONG_SECTION_NAMES
|| CONST_STRNEQ (name, GNU_LINKONCE_WI)
|| CONST_STRNEQ (name, GNU_LINKONCE_WT)
#endif
|| CONST_STRNEQ (name, ".stab"))
{
#ifdef COFF_PAGE_SIZE
sec_flags |= SEC_DEBUGGING;
#endif
}
#ifdef _LIB
else if (strcmp (name, _LIB) == 0)
;
#endif
#ifdef _LIT
else if (strcmp (name, _LIT) == 0)
sec_flags = SEC_LOAD | SEC_ALLOC | SEC_READONLY;
#endif
else
sec_flags |= SEC_ALLOC | SEC_LOAD;
#ifdef STYP_LIT /* A29k readonly text/data section type. */
if ((styp_flags & STYP_LIT) == STYP_LIT)
sec_flags = (SEC_LOAD | SEC_ALLOC | SEC_READONLY);
#endif /* STYP_LIT */
#ifdef STYP_OTHER_LOAD /* Other loaded sections. */
if (styp_flags & STYP_OTHER_LOAD)
sec_flags = (SEC_LOAD | SEC_ALLOC);
#endif /* STYP_SDATA */
#if defined (COFF_LONG_SECTION_NAMES) && defined (COFF_SUPPORT_GNU_LINKONCE)
/* As a GNU extension, if the name begins with .gnu.linkonce, we
only link a single copy of the section. This is used to support
g++. g++ will emit each template expansion in its own section.
The symbols will be defined as weak, so that multiple definitions
are permitted. The GNU linker extension is to actually discard
all but one of the sections. */
if (CONST_STRNEQ (name, ".gnu.linkonce"))
sec_flags |= SEC_LINK_ONCE | SEC_LINK_DUPLICATES_DISCARD;
#endif
if (flags_ptr == NULL)
return FALSE;
* flags_ptr = sec_flags;
return TRUE;
}
#else /* COFF_WITH_PE */
static flagword
handle_COMDAT (bfd * abfd,
flagword sec_flags,
void * hdr,
const char *name,
asection *section)
{
struct internal_scnhdr *internal_s = (struct internal_scnhdr *) hdr;
bfd_byte *esymstart, *esym, *esymend;
int seen_state = 0;
char *target_name = NULL;
sec_flags |= SEC_LINK_ONCE;
/* Unfortunately, the PE format stores essential information in
the symbol table, of all places. We need to extract that
information now, so that objdump and the linker will know how
to handle the section without worrying about the symbols. We
can't call slurp_symtab, because the linker doesn't want the
swapped symbols. */
/* COMDAT sections are special. The first symbol is the section
symbol, which tells what kind of COMDAT section it is. The
second symbol is the "comdat symbol" - the one with the
unique name. GNU uses the section symbol for the unique
name; MS uses ".text" for every comdat section. Sigh. - DJ */
/* This is not mirrored in sec_to_styp_flags(), but there
doesn't seem to be a need to, either, and it would at best be
rather messy. */
if (! _bfd_coff_get_external_symbols (abfd))
return sec_flags;
esymstart = esym = (bfd_byte *) obj_coff_external_syms (abfd);
esymend = esym + obj_raw_syment_count (abfd) * bfd_coff_symesz (abfd);
while (esym < esymend)
{
struct internal_syment isym;
char buf[SYMNMLEN + 1];
const char *symname;
bfd_coff_swap_sym_in (abfd, esym, & isym);
BFD_ASSERT (sizeof (internal_s->s_name) <= SYMNMLEN);
if (isym.n_scnum == section->target_index)
{
/* According to the MSVC documentation, the first
TWO entries with the section # are both of
interest to us. The first one is the "section
symbol" (section name). The second is the comdat
symbol name. Here, we've found the first
qualifying entry; we distinguish it from the
second with a state flag.
In the case of gas-generated (at least until that
is fixed) .o files, it isn't necessarily the
second one. It may be some other later symbol.
Since gas also doesn't follow MS conventions and
emits the section similar to .text$<name>, where
<something> is the name we're looking for, we
distinguish the two as follows:
If the section name is simply a section name (no
$) we presume it's MS-generated, and look at
precisely the second symbol for the comdat name.
If the section name has a $, we assume it's
gas-generated, and look for <something> (whatever
follows the $) as the comdat symbol. */
/* All 3 branches use this. */
symname = _bfd_coff_internal_syment_name (abfd, &isym, buf);
/* PR 17512 file: 078-11867-0.004 */
if (symname == NULL)
{
_bfd_error_handler (_("%B: unable to load COMDAT section name"), abfd);
break;
}
switch (seen_state)
{
case 0:
{
/* The first time we've seen the symbol. */
union internal_auxent aux;
/* If it isn't the stuff we're expecting, die;
The MS documentation is vague, but it
appears that the second entry serves BOTH
as the comdat symbol and the defining
symbol record (either C_STAT or C_EXT,
possibly with an aux entry with debug
information if it's a function.) It
appears the only way to find the second one
is to count. (On Intel, they appear to be
adjacent, but on Alpha, they have been
found separated.)
Here, we think we've found the first one,
but there's some checking we can do to be
sure. */
if (! ((isym.n_sclass == C_STAT
|| isym.n_sclass == C_EXT)
&& BTYPE (isym.n_type) == T_NULL
&& isym.n_value == 0))
abort ();