* configure.in (host==solaris): Pass only the first word of $CC
[deliverable/binutils-gdb.git] / bfd / syms.c
1 /* Generic symbol-table support for the BFD library.
2 Copyright (C) 1990, 91, 92, 93, 94, 95, 1996 Free Software Foundation, Inc.
3 Written by Cygnus Support.
4
5 This file is part of BFD, the Binary File Descriptor library.
6
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
11
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
20
21 /*
22 SECTION
23 Symbols
24
25 BFD tries to maintain as much symbol information as it can when
26 it moves information from file to file. BFD passes information
27 to applications though the <<asymbol>> structure. When the
28 application requests the symbol table, BFD reads the table in
29 the native form and translates parts of it into the internal
30 format. To maintain more than the information passed to
31 applications, some targets keep some information ``behind the
32 scenes'' in a structure only the particular back end knows
33 about. For example, the coff back end keeps the original
34 symbol table structure as well as the canonical structure when
35 a BFD is read in. On output, the coff back end can reconstruct
36 the output symbol table so that no information is lost, even
37 information unique to coff which BFD doesn't know or
38 understand. If a coff symbol table were read, but were written
39 through an a.out back end, all the coff specific information
40 would be lost. The symbol table of a BFD
41 is not necessarily read in until a canonicalize request is
42 made. Then the BFD back end fills in a table provided by the
43 application with pointers to the canonical information. To
44 output symbols, the application provides BFD with a table of
45 pointers to pointers to <<asymbol>>s. This allows applications
46 like the linker to output a symbol as it was read, since the ``behind
47 the scenes'' information will be still available.
48 @menu
49 @* Reading Symbols::
50 @* Writing Symbols::
51 @* Mini Symbols::
52 @* typedef asymbol::
53 @* symbol handling functions::
54 @end menu
55
56 INODE
57 Reading Symbols, Writing Symbols, Symbols, Symbols
58 SUBSECTION
59 Reading symbols
60
61 There are two stages to reading a symbol table from a BFD:
62 allocating storage, and the actual reading process. This is an
63 excerpt from an application which reads the symbol table:
64
65 | long storage_needed;
66 | asymbol **symbol_table;
67 | long number_of_symbols;
68 | long i;
69 |
70 | storage_needed = bfd_get_symtab_upper_bound (abfd);
71 |
72 | if (storage_needed < 0)
73 | FAIL
74 |
75 | if (storage_needed == 0) {
76 | return ;
77 | }
78 | symbol_table = (asymbol **) xmalloc (storage_needed);
79 | ...
80 | number_of_symbols =
81 | bfd_canonicalize_symtab (abfd, symbol_table);
82 |
83 | if (number_of_symbols < 0)
84 | FAIL
85 |
86 | for (i = 0; i < number_of_symbols; i++) {
87 | process_symbol (symbol_table[i]);
88 | }
89
90 All storage for the symbols themselves is in an obstack
91 connected to the BFD; it is freed when the BFD is closed.
92
93
94 INODE
95 Writing Symbols, Mini Symbols, Reading Symbols, Symbols
96 SUBSECTION
97 Writing symbols
98
99 Writing of a symbol table is automatic when a BFD open for
100 writing is closed. The application attaches a vector of
101 pointers to pointers to symbols to the BFD being written, and
102 fills in the symbol count. The close and cleanup code reads
103 through the table provided and performs all the necessary
104 operations. The BFD output code must always be provided with an
105 ``owned'' symbol: one which has come from another BFD, or one
106 which has been created using <<bfd_make_empty_symbol>>. Here is an
107 example showing the creation of a symbol table with only one element:
108
109 | #include "bfd.h"
110 | main()
111 | {
112 | bfd *abfd;
113 | asymbol *ptrs[2];
114 | asymbol *new;
115 |
116 | abfd = bfd_openw("foo","a.out-sunos-big");
117 | bfd_set_format(abfd, bfd_object);
118 | new = bfd_make_empty_symbol(abfd);
119 | new->name = "dummy_symbol";
120 | new->section = bfd_make_section_old_way(abfd, ".text");
121 | new->flags = BSF_GLOBAL;
122 | new->value = 0x12345;
123 |
124 | ptrs[0] = new;
125 | ptrs[1] = (asymbol *)0;
126 |
127 | bfd_set_symtab(abfd, ptrs, 1);
128 | bfd_close(abfd);
129 | }
130 |
131 | ./makesym
132 | nm foo
133 | 00012345 A dummy_symbol
134
135 Many formats cannot represent arbitary symbol information; for
136 instance, the <<a.out>> object format does not allow an
137 arbitary number of sections. A symbol pointing to a section
138 which is not one of <<.text>>, <<.data>> or <<.bss>> cannot
139 be described.
140
141 INODE
142 Mini Symbols, typedef asymbol, Writing Symbols, Symbols
143 SUBSECTION
144 Mini Symbols
145
146 Mini symbols provide read-only access to the symbol table.
147 They use less memory space, but require more time to access.
148 They can be useful for tools like nm or objdump, which may
149 have to handle symbol tables of extremely large executables.
150
151 The <<bfd_read_minisymbols>> function will read the symbols
152 into memory in an internal form. It will return a <<void *>>
153 pointer to a block of memory, a symbol count, and the size of
154 each symbol. The pointer is allocated using <<malloc>>, and
155 should be freed by the caller when it is no longer needed.
156
157 The function <<bfd_minisymbol_to_symbol>> will take a pointer
158 to a minisymbol, and a pointer to a structure returned by
159 <<bfd_make_empty_symbol>>, and return a <<asymbol>> structure.
160 The return value may or may not be the same as the value from
161 <<bfd_make_empty_symbol>> which was passed in.
162
163 */
164
165
166
167 /*
168 DOCDD
169 INODE
170 typedef asymbol, symbol handling functions, Mini Symbols, Symbols
171
172 */
173 /*
174 SUBSECTION
175 typedef asymbol
176
177 An <<asymbol>> has the form:
178
179 */
180
181 /*
182 CODE_FRAGMENT
183
184 .
185 .typedef struct symbol_cache_entry
186 .{
187 . {* A pointer to the BFD which owns the symbol. This information
188 . is necessary so that a back end can work out what additional
189 . information (invisible to the application writer) is carried
190 . with the symbol.
191 .
192 . This field is *almost* redundant, since you can use section->owner
193 . instead, except that some symbols point to the global sections
194 . bfd_{abs,com,und}_section. This could be fixed by making
195 . these globals be per-bfd (or per-target-flavor). FIXME. *}
196 .
197 . struct _bfd *the_bfd; {* Use bfd_asymbol_bfd(sym) to access this field. *}
198 .
199 . {* The text of the symbol. The name is left alone, and not copied; the
200 . application may not alter it. *}
201 . CONST char *name;
202 .
203 . {* The value of the symbol. This really should be a union of a
204 . numeric value with a pointer, since some flags indicate that
205 . a pointer to another symbol is stored here. *}
206 . symvalue value;
207 .
208 . {* Attributes of a symbol: *}
209 .
210 .#define BSF_NO_FLAGS 0x00
211 .
212 . {* The symbol has local scope; <<static>> in <<C>>. The value
213 . is the offset into the section of the data. *}
214 .#define BSF_LOCAL 0x01
215 .
216 . {* The symbol has global scope; initialized data in <<C>>. The
217 . value is the offset into the section of the data. *}
218 .#define BSF_GLOBAL 0x02
219 .
220 . {* The symbol has global scope and is exported. The value is
221 . the offset into the section of the data. *}
222 .#define BSF_EXPORT BSF_GLOBAL {* no real difference *}
223 .
224 . {* A normal C symbol would be one of:
225 . <<BSF_LOCAL>>, <<BSF_FORT_COMM>>, <<BSF_UNDEFINED>> or
226 . <<BSF_GLOBAL>> *}
227 .
228 . {* The symbol is a debugging record. The value has an arbitary
229 . meaning. *}
230 .#define BSF_DEBUGGING 0x08
231 .
232 . {* The symbol denotes a function entry point. Used in ELF,
233 . perhaps others someday. *}
234 .#define BSF_FUNCTION 0x10
235 .
236 . {* Used by the linker. *}
237 .#define BSF_KEEP 0x20
238 .#define BSF_KEEP_G 0x40
239 .
240 . {* A weak global symbol, overridable without warnings by
241 . a regular global symbol of the same name. *}
242 .#define BSF_WEAK 0x80
243 .
244 . {* This symbol was created to point to a section, e.g. ELF's
245 . STT_SECTION symbols. *}
246 .#define BSF_SECTION_SYM 0x100
247 .
248 . {* The symbol used to be a common symbol, but now it is
249 . allocated. *}
250 .#define BSF_OLD_COMMON 0x200
251 .
252 . {* The default value for common data. *}
253 .#define BFD_FORT_COMM_DEFAULT_VALUE 0
254 .
255 . {* In some files the type of a symbol sometimes alters its
256 . location in an output file - ie in coff a <<ISFCN>> symbol
257 . which is also <<C_EXT>> symbol appears where it was
258 . declared and not at the end of a section. This bit is set
259 . by the target BFD part to convey this information. *}
260 .
261 .#define BSF_NOT_AT_END 0x400
262 .
263 . {* Signal that the symbol is the label of constructor section. *}
264 .#define BSF_CONSTRUCTOR 0x800
265 .
266 . {* Signal that the symbol is a warning symbol. The name is a
267 . warning. The name of the next symbol is the one to warn about;
268 . if a reference is made to a symbol with the same name as the next
269 . symbol, a warning is issued by the linker. *}
270 .#define BSF_WARNING 0x1000
271 .
272 . {* Signal that the symbol is indirect. This symbol is an indirect
273 . pointer to the symbol with the same name as the next symbol. *}
274 .#define BSF_INDIRECT 0x2000
275 .
276 . {* BSF_FILE marks symbols that contain a file name. This is used
277 . for ELF STT_FILE symbols. *}
278 .#define BSF_FILE 0x4000
279 .
280 . {* Symbol is from dynamic linking information. *}
281 .#define BSF_DYNAMIC 0x8000
282 .
283 . {* The symbol denotes a data object. Used in ELF, and perhaps
284 . others someday. *}
285 .#define BSF_OBJECT 0x10000
286 .
287 . flagword flags;
288 .
289 . {* A pointer to the section to which this symbol is
290 . relative. This will always be non NULL, there are special
291 . sections for undefined and absolute symbols. *}
292 . struct sec *section;
293 .
294 . {* Back end special data. *}
295 . union
296 . {
297 . PTR p;
298 . bfd_vma i;
299 . } udata;
300 .
301 .} asymbol;
302 */
303
304 #include "bfd.h"
305 #include "sysdep.h"
306 #include "libbfd.h"
307 #include "bfdlink.h"
308 #include "aout/stab_gnu.h"
309
310 /*
311 DOCDD
312 INODE
313 symbol handling functions, , typedef asymbol, Symbols
314 SUBSECTION
315 Symbol handling functions
316 */
317
318 /*
319 FUNCTION
320 bfd_get_symtab_upper_bound
321
322 DESCRIPTION
323 Return the number of bytes required to store a vector of pointers
324 to <<asymbols>> for all the symbols in the BFD @var{abfd},
325 including a terminal NULL pointer. If there are no symbols in
326 the BFD, then return 0. If an error occurs, return -1.
327
328 .#define bfd_get_symtab_upper_bound(abfd) \
329 . BFD_SEND (abfd, _bfd_get_symtab_upper_bound, (abfd))
330
331 */
332
333 /*
334 FUNCTION
335 bfd_is_local_label
336
337 SYNOPSIS
338 boolean bfd_is_local_label(bfd *abfd, asymbol *sym);
339
340 DESCRIPTION
341 Return true if the given symbol @var{sym} in the BFD @var{abfd} is
342 a compiler generated local label, else return false.
343 .#define bfd_is_local_label(abfd, sym) \
344 . BFD_SEND (abfd, _bfd_is_local_label,(abfd, sym))
345 */
346
347 /*
348 FUNCTION
349 bfd_canonicalize_symtab
350
351 DESCRIPTION
352 Read the symbols from the BFD @var{abfd}, and fills in
353 the vector @var{location} with pointers to the symbols and
354 a trailing NULL.
355 Return the actual number of symbol pointers, not
356 including the NULL.
357
358
359 .#define bfd_canonicalize_symtab(abfd, location) \
360 . BFD_SEND (abfd, _bfd_canonicalize_symtab,\
361 . (abfd, location))
362
363 */
364
365
366 /*
367 FUNCTION
368 bfd_set_symtab
369
370 SYNOPSIS
371 boolean bfd_set_symtab (bfd *abfd, asymbol **location, unsigned int count);
372
373 DESCRIPTION
374 Arrange that when the output BFD @var{abfd} is closed,
375 the table @var{location} of @var{count} pointers to symbols
376 will be written.
377 */
378
379 boolean
380 bfd_set_symtab (abfd, location, symcount)
381 bfd *abfd;
382 asymbol **location;
383 unsigned int symcount;
384 {
385 if ((abfd->format != bfd_object) || (bfd_read_p (abfd)))
386 {
387 bfd_set_error (bfd_error_invalid_operation);
388 return false;
389 }
390
391 bfd_get_outsymbols (abfd) = location;
392 bfd_get_symcount (abfd) = symcount;
393 return true;
394 }
395
396 /*
397 FUNCTION
398 bfd_print_symbol_vandf
399
400 SYNOPSIS
401 void bfd_print_symbol_vandf(PTR file, asymbol *symbol);
402
403 DESCRIPTION
404 Print the value and flags of the @var{symbol} supplied to the
405 stream @var{file}.
406 */
407 void
408 bfd_print_symbol_vandf (arg, symbol)
409 PTR arg;
410 asymbol *symbol;
411 {
412 FILE *file = (FILE *) arg;
413 flagword type = symbol->flags;
414 if (symbol->section != (asection *) NULL)
415 {
416 fprintf_vma (file, symbol->value + symbol->section->vma);
417 }
418 else
419 {
420 fprintf_vma (file, symbol->value);
421 }
422
423 /* This presumes that a symbol can not be both BSF_DEBUGGING and
424 BSF_DYNAMIC, nor more than one of BSF_FUNCTION, BSF_FILE, and
425 BSF_OBJECT. */
426 fprintf (file, " %c%c%c%c%c%c%c",
427 ((type & BSF_LOCAL)
428 ? (type & BSF_GLOBAL) ? '!' : 'l'
429 : (type & BSF_GLOBAL) ? 'g' : ' '),
430 (type & BSF_WEAK) ? 'w' : ' ',
431 (type & BSF_CONSTRUCTOR) ? 'C' : ' ',
432 (type & BSF_WARNING) ? 'W' : ' ',
433 (type & BSF_INDIRECT) ? 'I' : ' ',
434 (type & BSF_DEBUGGING) ? 'd' : (type & BSF_DYNAMIC) ? 'D' : ' ',
435 ((type & BSF_FUNCTION)
436 ? 'F'
437 : ((type & BSF_FILE)
438 ? 'f'
439 : ((type & BSF_OBJECT) ? 'O' : ' '))));
440 }
441
442
443 /*
444 FUNCTION
445 bfd_make_empty_symbol
446
447 DESCRIPTION
448 Create a new <<asymbol>> structure for the BFD @var{abfd}
449 and return a pointer to it.
450
451 This routine is necessary because each back end has private
452 information surrounding the <<asymbol>>. Building your own
453 <<asymbol>> and pointing to it will not create the private
454 information, and will cause problems later on.
455
456 .#define bfd_make_empty_symbol(abfd) \
457 . BFD_SEND (abfd, _bfd_make_empty_symbol, (abfd))
458 */
459
460 /*
461 FUNCTION
462 bfd_make_debug_symbol
463
464 DESCRIPTION
465 Create a new <<asymbol>> structure for the BFD @var{abfd},
466 to be used as a debugging symbol. Further details of its use have
467 yet to be worked out.
468
469 .#define bfd_make_debug_symbol(abfd,ptr,size) \
470 . BFD_SEND (abfd, _bfd_make_debug_symbol, (abfd, ptr, size))
471 */
472
473 struct section_to_type
474 {
475 CONST char *section;
476 char type;
477 };
478
479 /* Map section names to POSIX/BSD single-character symbol types.
480 This table is probably incomplete. It is sorted for convenience of
481 adding entries. Since it is so short, a linear search is used. */
482 static CONST struct section_to_type stt[] =
483 {
484 {"*DEBUG*", 'N'},
485 {".bss", 'b'},
486 {".data", 'd'},
487 {".rdata", 'r'}, /* Read only data. */
488 {".rodata", 'r'}, /* Read only data. */
489 {".sbss", 's'}, /* Small BSS (uninitialized data). */
490 {".scommon", 'c'}, /* Small common. */
491 {".sdata", 'g'}, /* Small initialized data. */
492 {".text", 't'},
493 {0, 0}
494 };
495
496 /* Return the single-character symbol type corresponding to
497 section S, or '?' for an unknown COFF section.
498
499 Check for any leading string which matches, so .text5 returns
500 't' as well as .text */
501
502 static char
503 coff_section_type (s)
504 char *s;
505 {
506 CONST struct section_to_type *t;
507
508 for (t = &stt[0]; t->section; t++)
509 if (!strncmp (s, t->section, strlen (t->section)))
510 return t->type;
511
512 return '?';
513 }
514
515 #ifndef islower
516 #define islower(c) ((c) >= 'a' && (c) <= 'z')
517 #endif
518 #ifndef toupper
519 #define toupper(c) (islower(c) ? ((c) & ~0x20) : (c))
520 #endif
521
522 /*
523 FUNCTION
524 bfd_decode_symclass
525
526 DESCRIPTION
527 Return a character corresponding to the symbol
528 class of @var{symbol}, or '?' for an unknown class.
529
530 SYNOPSIS
531 int bfd_decode_symclass(asymbol *symbol);
532 */
533 int
534 bfd_decode_symclass (symbol)
535 asymbol *symbol;
536 {
537 char c;
538
539 if (bfd_is_com_section (symbol->section))
540 return 'C';
541 if (bfd_is_und_section (symbol->section))
542 return 'U';
543 if (bfd_is_ind_section (symbol->section))
544 return 'I';
545 if (symbol->flags & BSF_WEAK)
546 return 'W';
547 if (!(symbol->flags & (BSF_GLOBAL | BSF_LOCAL)))
548 return '?';
549
550 if (bfd_is_abs_section (symbol->section))
551 c = 'a';
552 else if (symbol->section)
553 c = coff_section_type (symbol->section->name);
554 else
555 return '?';
556 if (symbol->flags & BSF_GLOBAL)
557 c = toupper (c);
558 return c;
559
560 /* We don't have to handle these cases just yet, but we will soon:
561 N_SETV: 'v';
562 N_SETA: 'l';
563 N_SETT: 'x';
564 N_SETD: 'z';
565 N_SETB: 's';
566 N_INDR: 'i';
567 */
568 }
569
570 /*
571 FUNCTION
572 bfd_symbol_info
573
574 DESCRIPTION
575 Fill in the basic info about symbol that nm needs.
576 Additional info may be added by the back-ends after
577 calling this function.
578
579 SYNOPSIS
580 void bfd_symbol_info(asymbol *symbol, symbol_info *ret);
581 */
582
583 void
584 bfd_symbol_info (symbol, ret)
585 asymbol *symbol;
586 symbol_info *ret;
587 {
588 ret->type = bfd_decode_symclass (symbol);
589 if (ret->type != 'U')
590 ret->value = symbol->value + symbol->section->vma;
591 else
592 ret->value = 0;
593 ret->name = symbol->name;
594 }
595
596 void
597 bfd_symbol_is_absolute ()
598 {
599 abort ();
600 }
601
602 /*
603 FUNCTION
604 bfd_copy_private_symbol_data
605
606 SYNOPSIS
607 boolean bfd_copy_private_symbol_data(bfd *ibfd, asymbol *isym, bfd *obfd, asymbol *osym);
608
609 DESCRIPTION
610 Copy private symbol information from @var{isym} in the BFD
611 @var{ibfd} to the symbol @var{osym} in the BFD @var{obfd}.
612 Return <<true>> on success, <<false>> on error. Possible error
613 returns are:
614
615 o <<bfd_error_no_memory>> -
616 Not enough memory exists to create private data for @var{osec}.
617
618 .#define bfd_copy_private_symbol_data(ibfd, isymbol, obfd, osymbol) \
619 . BFD_SEND (ibfd, _bfd_copy_private_symbol_data, \
620 . (ibfd, isymbol, obfd, osymbol))
621
622 */
623
624 /* The generic version of the function which returns mini symbols.
625 This is used when the backend does not provide a more efficient
626 version. It just uses BFD asymbol structures as mini symbols. */
627
628 long
629 _bfd_generic_read_minisymbols (abfd, dynamic, minisymsp, sizep)
630 bfd *abfd;
631 boolean dynamic;
632 PTR *minisymsp;
633 unsigned int *sizep;
634 {
635 long storage;
636 asymbol **syms = NULL;
637 long symcount;
638
639 if (dynamic)
640 storage = bfd_get_dynamic_symtab_upper_bound (abfd);
641 else
642 storage = bfd_get_symtab_upper_bound (abfd);
643 if (storage < 0)
644 goto error_return;
645
646 syms = (asymbol **) bfd_malloc ((size_t) storage);
647 if (syms == NULL)
648 goto error_return;
649
650 if (dynamic)
651 symcount = bfd_canonicalize_dynamic_symtab (abfd, syms);
652 else
653 symcount = bfd_canonicalize_symtab (abfd, syms);
654 if (symcount < 0)
655 goto error_return;
656
657 *minisymsp = (PTR) syms;
658 *sizep = sizeof (asymbol *);
659 return symcount;
660
661 error_return:
662 if (syms != NULL)
663 free (syms);
664 return -1;
665 }
666
667 /* The generic version of the function which converts a minisymbol to
668 an asymbol. We don't worry about the sym argument we are passed;
669 we just return the asymbol the minisymbol points to. */
670
671 /*ARGSUSED*/
672 asymbol *
673 _bfd_generic_minisymbol_to_symbol (abfd, dynamic, minisym, sym)
674 bfd *abfd;
675 boolean dynamic;
676 const PTR minisym;
677 asymbol *sym;
678 {
679 return *(asymbol **) minisym;
680 }
681
682 /* Look through stabs debugging information in .stab and .stabstr
683 sections to find the source file and line closest to a desired
684 location. This is used by COFF and ELF targets. It sets *pfound
685 to true if it finds some information. The *pinfo field is used to
686 pass cached information in and out of this routine; this first time
687 the routine is called for a BFD, *pinfo should be NULL. The value
688 placed in *pinfo should be saved with the BFD, and passed back each
689 time this function is called. */
690
691 /* A pointer to this structure is stored in *pinfo. */
692
693 struct stab_find_info
694 {
695 /* The .stab section. */
696 asection *stabsec;
697 /* The .stabstr section. */
698 asection *strsec;
699 /* The contents of the .stab section. */
700 bfd_byte *stabs;
701 /* The contents of the .stabstr section. */
702 bfd_byte *strs;
703 /* An malloc buffer to hold the file name. */
704 char *filename;
705 /* Cached values to restart quickly. */
706 bfd_vma cached_offset;
707 bfd_byte *cached_stab;
708 bfd_byte *cached_str;
709 bfd_size_type cached_stroff;
710 };
711
712 boolean
713 _bfd_stab_section_find_nearest_line (abfd, symbols, section, offset, pfound,
714 pfilename, pfnname, pline, pinfo)
715 bfd *abfd;
716 asymbol **symbols;
717 asection *section;
718 bfd_vma offset;
719 boolean *pfound;
720 const char **pfilename;
721 const char **pfnname;
722 unsigned int *pline;
723 PTR *pinfo;
724 {
725 struct stab_find_info *info;
726 bfd_size_type stabsize, strsize;
727 bfd_byte *stab, *stabend, *str;
728 bfd_size_type stroff;
729 bfd_vma fnaddr;
730 char *directory_name, *main_file_name, *current_file_name, *line_file_name;
731 char *fnname;
732 bfd_vma low_func_vma, low_line_vma;
733
734 *pfound = false;
735 *pfilename = bfd_get_filename (abfd);
736 *pfnname = NULL;
737 *pline = 0;
738
739 info = (struct stab_find_info *) *pinfo;
740 if (info != NULL)
741 {
742 if (info->stabsec == NULL || info->strsec == NULL)
743 {
744 /* No stabs debugging information. */
745 return true;
746 }
747
748 stabsize = info->stabsec->_raw_size;
749 strsize = info->strsec->_raw_size;
750 }
751 else
752 {
753 long reloc_size, reloc_count;
754 arelent **reloc_vector;
755
756 info = (struct stab_find_info *) bfd_zalloc (abfd, sizeof *info);
757 if (info == NULL)
758 return false;
759
760 /* FIXME: When using the linker --split-by-file or
761 --split-by-reloc options, it is possible for the .stab and
762 .stabstr sections to be split. We should handle that. */
763
764 info->stabsec = bfd_get_section_by_name (abfd, ".stab");
765 info->strsec = bfd_get_section_by_name (abfd, ".stabstr");
766
767 if (info->stabsec == NULL || info->strsec == NULL)
768 {
769 /* No stabs debugging information. Set *pinfo so that we
770 can return quickly in the info != NULL case above. */
771 *pinfo = info;
772 return true;
773 }
774
775 stabsize = info->stabsec->_raw_size;
776 strsize = info->strsec->_raw_size;
777
778 info->stabs = (bfd_byte *) bfd_alloc (abfd, stabsize);
779 info->strs = (bfd_byte *) bfd_alloc (abfd, strsize);
780 if (info->stabs == NULL || info->strs == NULL)
781 return false;
782
783 if (! bfd_get_section_contents (abfd, info->stabsec, info->stabs, 0,
784 stabsize)
785 || ! bfd_get_section_contents (abfd, info->strsec, info->strs, 0,
786 strsize))
787 return false;
788
789 /* If this is a relocateable object file, we have to relocate
790 the entries in .stab. This should always be simple 32 bit
791 relocations against symbols defined in this object file, so
792 this should be no big deal. */
793 reloc_size = bfd_get_reloc_upper_bound (abfd, info->stabsec);
794 if (reloc_size < 0)
795 return false;
796 reloc_vector = (arelent **) bfd_malloc (reloc_size);
797 if (reloc_vector == NULL && reloc_size != 0)
798 return false;
799 reloc_count = bfd_canonicalize_reloc (abfd, info->stabsec, reloc_vector,
800 symbols);
801 if (reloc_count < 0)
802 {
803 if (reloc_vector != NULL)
804 free (reloc_vector);
805 return false;
806 }
807 if (reloc_count > 0)
808 {
809 arelent **pr;
810
811 for (pr = reloc_vector; *pr != NULL; pr++)
812 {
813 arelent *r;
814 unsigned long val;
815 asymbol *sym;
816
817 r = *pr;
818 if (r->howto->rightshift != 0
819 || r->howto->size != 2
820 || r->howto->bitsize != 32
821 || r->howto->pc_relative
822 || r->howto->bitpos != 0
823 || r->howto->dst_mask != 0xffffffff)
824 {
825 (*_bfd_error_handler)
826 ("Unsupported .stab relocation");
827 bfd_set_error (bfd_error_invalid_operation);
828 if (reloc_vector != NULL)
829 free (reloc_vector);
830 return false;
831 }
832
833 val = bfd_get_32 (abfd, info->stabs + r->address);
834 val &= r->howto->src_mask;
835 sym = *r->sym_ptr_ptr;
836 val += sym->value + sym->section->vma + r->addend;
837 bfd_put_32 (abfd, val, info->stabs + r->address);
838 }
839 }
840
841 if (reloc_vector != NULL)
842 free (reloc_vector);
843
844 *pinfo = info;
845 }
846
847 /* We are passed a section relative offset. The offsets in the
848 stabs information are absolute. */
849 offset += bfd_get_section_vma (abfd, section);
850
851 /* Stabs entries use a 12 byte format:
852 4 byte string table index
853 1 byte stab type
854 1 byte stab other field
855 2 byte stab desc field
856 4 byte stab value
857 FIXME: This will have to change for a 64 bit object format.
858
859 The stabs symbols are divided into compilation units. For the
860 first entry in each unit, the type of 0, the value is the length
861 of the string table for this unit, and the desc field is the
862 number of stabs symbols for this unit. */
863
864 #define STRDXOFF (0)
865 #define TYPEOFF (4)
866 #define OTHEROFF (5)
867 #define DESCOFF (6)
868 #define VALOFF (8)
869 #define STABSIZE (12)
870
871 /* It would be nice if we could skip ahead to the stabs symbols for
872 the next compilation unit to quickly scan through the compilation
873 units. Unfortunately, since each line number gets a separate
874 stabs entry, it is entirely plausible that a large source file
875 will overflow the 16 bit count of stabs entries. */
876 fnaddr = 0;
877 directory_name = NULL;
878 main_file_name = NULL;
879 current_file_name = NULL;
880 line_file_name = NULL;
881 fnname = NULL;
882 low_func_vma = 0;
883 low_line_vma = 0;
884
885 stabend = info->stabs + stabsize;
886
887 if (info->cached_stab == NULL || offset < info->cached_offset)
888 {
889 stab = info->stabs;
890 str = info->strs;
891 stroff = 0;
892 }
893 else
894 {
895 stab = info->cached_stab;
896 str = info->cached_str;
897 stroff = info->cached_stroff;
898 }
899
900 info->cached_offset = offset;
901
902 for (; stab < stabend; stab += STABSIZE)
903 {
904 boolean done;
905 bfd_vma val;
906 char *name;
907
908 done = false;
909
910 switch (stab[TYPEOFF])
911 {
912 case 0:
913 /* This is the first entry in a compilation unit. */
914 if ((bfd_size_type) ((info->strs + strsize) - str) < stroff)
915 {
916 done = true;
917 break;
918 }
919 str += stroff;
920 stroff = bfd_get_32 (abfd, stab + VALOFF);
921 break;
922
923 case N_SO:
924 /* The main file name. */
925
926 val = bfd_get_32 (abfd, stab + VALOFF);
927 if (val > offset)
928 {
929 done = true;
930 break;
931 }
932
933 name = str + bfd_get_32 (abfd, stab + STRDXOFF);
934
935 /* An empty string indicates the end of the compilation
936 unit. */
937 if (*name == '\0')
938 {
939 /* If there are functions in different sections, they
940 may have addresses larger than val, but we don't want
941 to forget the file name. When there are functions in
942 different cases, there is supposed to be an N_FUN at
943 the end of the function indicating where it ends. */
944 if (low_func_vma < val || fnname == NULL)
945 main_file_name = NULL;
946 break;
947 }
948
949 /* We know that we have to get to at least this point in the
950 stabs entries for this offset. */
951 info->cached_stab = stab;
952 info->cached_str = str;
953 info->cached_stroff = stroff;
954
955 current_file_name = name;
956
957 /* Look ahead to the next symbol. Two consecutive N_SO
958 symbols are a directory and a file name. */
959 if (stab + STABSIZE >= stabend
960 || *(stab + STABSIZE + TYPEOFF) != N_SO)
961 directory_name = NULL;
962 else
963 {
964 stab += STABSIZE;
965 directory_name = current_file_name;
966 current_file_name = str + bfd_get_32 (abfd, stab + STRDXOFF);
967 }
968
969 main_file_name = current_file_name;
970
971 break;
972
973 case N_SOL:
974 /* The name of an include file. */
975 current_file_name = str + bfd_get_32 (abfd, stab + STRDXOFF);
976 break;
977
978 case N_SLINE:
979 case N_DSLINE:
980 case N_BSLINE:
981 /* A line number. The value is relative to the start of the
982 current function. */
983 val = fnaddr + bfd_get_32 (abfd, stab + VALOFF);
984 if (val >= low_line_vma && val <= offset)
985 {
986 *pline = bfd_get_16 (abfd, stab + DESCOFF);
987 low_line_vma = val;
988 line_file_name = current_file_name;
989 }
990 break;
991
992 case N_FUN:
993 /* A function name. */
994 val = bfd_get_32 (abfd, stab + VALOFF);
995 name = str + bfd_get_32 (abfd, stab + STRDXOFF);
996
997 /* An empty string here indicates the end of a function, and
998 the value is relative to fnaddr. */
999
1000 if (*name == '\0')
1001 {
1002 val += fnaddr;
1003 if (val >= low_func_vma && val < offset)
1004 fnname = NULL;
1005 }
1006 else
1007 {
1008 if (val >= low_func_vma && val <= offset)
1009 {
1010 fnname = name;
1011 low_func_vma = val;
1012 }
1013
1014 fnaddr = val;
1015 }
1016
1017 break;
1018 }
1019
1020 if (done)
1021 break;
1022 }
1023
1024 if (main_file_name == NULL)
1025 {
1026 /* No information found. */
1027 return true;
1028 }
1029
1030 *pfound = true;
1031
1032 if (*pline != 0)
1033 main_file_name = line_file_name;
1034
1035 if (main_file_name != NULL)
1036 {
1037 if (main_file_name[0] == '/' || directory_name == NULL)
1038 *pfilename = main_file_name;
1039 else
1040 {
1041 size_t dirlen;
1042
1043 dirlen = strlen (directory_name);
1044 if (info->filename == NULL
1045 || strncmp (info->filename, directory_name, dirlen) != 0
1046 || strcmp (info->filename + dirlen, main_file_name) != 0)
1047 {
1048 if (info->filename != NULL)
1049 free (info->filename);
1050 info->filename = (char *) bfd_malloc (dirlen +
1051 strlen (main_file_name)
1052 + 1);
1053 if (info->filename == NULL)
1054 return false;
1055 strcpy (info->filename, directory_name);
1056 strcpy (info->filename + dirlen, main_file_name);
1057 }
1058
1059 *pfilename = info->filename;
1060 }
1061 }
1062
1063 if (fnname != NULL)
1064 {
1065 char *s;
1066
1067 /* This will typically be something like main:F(0,1), so we want
1068 to clobber the colon. It's OK to change the name, since the
1069 string is in our own local storage anyhow. */
1070
1071 s = strchr (fnname, ':');
1072 if (s != NULL)
1073 *s = '\0';
1074
1075 *pfnname = fnname;
1076 }
1077
1078 return true;
1079 }
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