* config/tc-d30v.c (md_parse_option <arg>): Add ATTRIBUTE_UNUSED.
[binutils.git] / bfd / syms.c
blobd95589bec03ca311407ca31822393fa16d0d6cc9
1 /* Generic symbol-table support for the BFD library.
2 Copyright 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
3 2000, 2001, 2002
4 Free Software Foundation, Inc.
5 Written by Cygnus Support.
7 This file is part of BFD, the Binary File Descriptor library.
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 2 of the License, or
12 (at your option) any later version.
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with this program; if not, write to the Free Software
21 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
24 SECTION
25 Symbols
27 BFD tries to maintain as much symbol information as it can when
28 it moves information from file to file. BFD passes information
29 to applications though the <<asymbol>> structure. When the
30 application requests the symbol table, BFD reads the table in
31 the native form and translates parts of it into the internal
32 format. To maintain more than the information passed to
33 applications, some targets keep some information ``behind the
34 scenes'' in a structure only the particular back end knows
35 about. For example, the coff back end keeps the original
36 symbol table structure as well as the canonical structure when
37 a BFD is read in. On output, the coff back end can reconstruct
38 the output symbol table so that no information is lost, even
39 information unique to coff which BFD doesn't know or
40 understand. If a coff symbol table were read, but were written
41 through an a.out back end, all the coff specific information
42 would be lost. The symbol table of a BFD
43 is not necessarily read in until a canonicalize request is
44 made. Then the BFD back end fills in a table provided by the
45 application with pointers to the canonical information. To
46 output symbols, the application provides BFD with a table of
47 pointers to pointers to <<asymbol>>s. This allows applications
48 like the linker to output a symbol as it was read, since the ``behind
49 the scenes'' information will be still available.
50 @menu
51 @* Reading Symbols::
52 @* Writing Symbols::
53 @* Mini Symbols::
54 @* typedef asymbol::
55 @* symbol handling functions::
56 @end menu
58 INODE
59 Reading Symbols, Writing Symbols, Symbols, Symbols
60 SUBSECTION
61 Reading symbols
63 There are two stages to reading a symbol table from a BFD:
64 allocating storage, and the actual reading process. This is an
65 excerpt from an application which reads the symbol table:
67 | long storage_needed;
68 | asymbol **symbol_table;
69 | long number_of_symbols;
70 | long i;
72 | storage_needed = bfd_get_symtab_upper_bound (abfd);
74 | if (storage_needed < 0)
75 | FAIL
77 | if (storage_needed == 0) {
78 | return ;
79 | }
80 | symbol_table = (asymbol **) xmalloc (storage_needed);
81 | ...
82 | number_of_symbols =
83 | bfd_canonicalize_symtab (abfd, symbol_table);
85 | if (number_of_symbols < 0)
86 | FAIL
88 | for (i = 0; i < number_of_symbols; i++) {
89 | process_symbol (symbol_table[i]);
90 | }
92 All storage for the symbols themselves is in an objalloc
93 connected to the BFD; it is freed when the BFD is closed.
95 INODE
96 Writing Symbols, Mini Symbols, Reading Symbols, Symbols
97 SUBSECTION
98 Writing symbols
100 Writing of a symbol table is automatic when a BFD open for
101 writing is closed. The application attaches a vector of
102 pointers to pointers to symbols to the BFD being written, and
103 fills in the symbol count. The close and cleanup code reads
104 through the table provided and performs all the necessary
105 operations. The BFD output code must always be provided with an
106 ``owned'' symbol: one which has come from another BFD, or one
107 which has been created using <<bfd_make_empty_symbol>>. Here is an
108 example showing the creation of a symbol table with only one element:
110 | #include "bfd.h"
111 | main()
113 | bfd *abfd;
114 | asymbol *ptrs[2];
115 | asymbol *new;
117 | abfd = bfd_openw("foo","a.out-sunos-big");
118 | bfd_set_format(abfd, bfd_object);
119 | new = bfd_make_empty_symbol(abfd);
120 | new->name = "dummy_symbol";
121 | new->section = bfd_make_section_old_way(abfd, ".text");
122 | new->flags = BSF_GLOBAL;
123 | new->value = 0x12345;
125 | ptrs[0] = new;
126 | ptrs[1] = (asymbol *)0;
128 | bfd_set_symtab(abfd, ptrs, 1);
129 | bfd_close(abfd);
132 | ./makesym
133 | nm foo
134 | 00012345 A dummy_symbol
136 Many formats cannot represent arbitary symbol information; for
137 instance, the <<a.out>> object format does not allow an
138 arbitary number of sections. A symbol pointing to a section
139 which is not one of <<.text>>, <<.data>> or <<.bss>> cannot
140 be described.
142 INODE
143 Mini Symbols, typedef asymbol, Writing Symbols, Symbols
144 SUBSECTION
145 Mini Symbols
147 Mini symbols provide read-only access to the symbol table.
148 They use less memory space, but require more time to access.
149 They can be useful for tools like nm or objdump, which may
150 have to handle symbol tables of extremely large executables.
152 The <<bfd_read_minisymbols>> function will read the symbols
153 into memory in an internal form. It will return a <<void *>>
154 pointer to a block of memory, a symbol count, and the size of
155 each symbol. The pointer is allocated using <<malloc>>, and
156 should be freed by the caller when it is no longer needed.
158 The function <<bfd_minisymbol_to_symbol>> will take a pointer
159 to a minisymbol, and a pointer to a structure returned by
160 <<bfd_make_empty_symbol>>, and return a <<asymbol>> structure.
161 The return value may or may not be the same as the value from
162 <<bfd_make_empty_symbol>> which was passed in.
167 DOCDD
168 INODE
169 typedef asymbol, symbol handling functions, Mini Symbols, Symbols
173 SUBSECTION
174 typedef asymbol
176 An <<asymbol>> has the form:
181 CODE_FRAGMENT
184 .typedef struct symbol_cache_entry
186 . {* A pointer to the BFD which owns the symbol. This information
187 . is necessary so that a back end can work out what additional
188 . information (invisible to the application writer) is carried
189 . with the symbol.
191 . This field is *almost* redundant, since you can use section->owner
192 . instead, except that some symbols point to the global sections
193 . bfd_{abs,com,und}_section. This could be fixed by making
194 . these globals be per-bfd (or per-target-flavor). FIXME. *}
195 . struct _bfd *the_bfd; {* Use bfd_asymbol_bfd(sym) to access this field. *}
197 . {* The text of the symbol. The name is left alone, and not copied; the
198 . application may not alter it. *}
199 . const char *name;
201 . {* The value of the symbol. This really should be a union of a
202 . numeric value with a pointer, since some flags indicate that
203 . a pointer to another symbol is stored here. *}
204 . symvalue value;
206 . {* Attributes of a symbol. *}
207 .#define BSF_NO_FLAGS 0x00
209 . {* The symbol has local scope; <<static>> in <<C>>. The value
210 . is the offset into the section of the data. *}
211 .#define BSF_LOCAL 0x01
213 . {* The symbol has global scope; initialized data in <<C>>. The
214 . value is the offset into the section of the data. *}
215 .#define BSF_GLOBAL 0x02
217 . {* The symbol has global scope and is exported. The value is
218 . the offset into the section of the data. *}
219 .#define BSF_EXPORT BSF_GLOBAL {* No real difference. *}
221 . {* A normal C symbol would be one of:
222 . <<BSF_LOCAL>>, <<BSF_FORT_COMM>>, <<BSF_UNDEFINED>> or
223 . <<BSF_GLOBAL>>. *}
225 . {* The symbol is a debugging record. The value has an arbitary
226 . meaning, unless BSF_DEBUGGING_RELOC is also set. *}
227 .#define BSF_DEBUGGING 0x08
229 . {* The symbol denotes a function entry point. Used in ELF,
230 . perhaps others someday. *}
231 .#define BSF_FUNCTION 0x10
233 . {* Used by the linker. *}
234 .#define BSF_KEEP 0x20
235 .#define BSF_KEEP_G 0x40
237 . {* A weak global symbol, overridable without warnings by
238 . a regular global symbol of the same name. *}
239 .#define BSF_WEAK 0x80
241 . {* This symbol was created to point to a section, e.g. ELF's
242 . STT_SECTION symbols. *}
243 .#define BSF_SECTION_SYM 0x100
245 . {* The symbol used to be a common symbol, but now it is
246 . allocated. *}
247 .#define BSF_OLD_COMMON 0x200
249 . {* The default value for common data. *}
250 .#define BFD_FORT_COMM_DEFAULT_VALUE 0
252 . {* In some files the type of a symbol sometimes alters its
253 . location in an output file - ie in coff a <<ISFCN>> symbol
254 . which is also <<C_EXT>> symbol appears where it was
255 . declared and not at the end of a section. This bit is set
256 . by the target BFD part to convey this information. *}
257 .#define BSF_NOT_AT_END 0x400
259 . {* Signal that the symbol is the label of constructor section. *}
260 .#define BSF_CONSTRUCTOR 0x800
262 . {* Signal that the symbol is a warning symbol. The name is a
263 . warning. The name of the next symbol is the one to warn about;
264 . if a reference is made to a symbol with the same name as the next
265 . symbol, a warning is issued by the linker. *}
266 .#define BSF_WARNING 0x1000
268 . {* Signal that the symbol is indirect. This symbol is an indirect
269 . pointer to the symbol with the same name as the next symbol. *}
270 .#define BSF_INDIRECT 0x2000
272 . {* BSF_FILE marks symbols that contain a file name. This is used
273 . for ELF STT_FILE symbols. *}
274 .#define BSF_FILE 0x4000
276 . {* Symbol is from dynamic linking information. *}
277 .#define BSF_DYNAMIC 0x8000
279 . {* The symbol denotes a data object. Used in ELF, and perhaps
280 . others someday. *}
281 .#define BSF_OBJECT 0x10000
283 . {* This symbol is a debugging symbol. The value is the offset
284 . into the section of the data. BSF_DEBUGGING should be set
285 . as well. *}
286 .#define BSF_DEBUGGING_RELOC 0x20000
288 . {* This symbol is thread local. Used in ELF. *}
289 .#define BSF_THREAD_LOCAL 0x40000
291 . flagword flags;
293 . {* A pointer to the section to which this symbol is
294 . relative. This will always be non NULL, there are special
295 . sections for undefined and absolute symbols. *}
296 . struct sec *section;
298 . {* Back end special data. *}
299 . union
301 . PTR p;
302 . bfd_vma i;
304 . udata;
306 .asymbol;
310 #include "bfd.h"
311 #include "sysdep.h"
312 #include "libbfd.h"
313 #include "safe-ctype.h"
314 #include "bfdlink.h"
315 #include "aout/stab_gnu.h"
317 static char coff_section_type PARAMS ((const char *));
318 static char decode_section_type PARAMS ((const struct sec *));
319 static int cmpindexentry PARAMS ((const PTR, const PTR));
322 DOCDD
323 INODE
324 symbol handling functions, , typedef asymbol, Symbols
325 SUBSECTION
326 Symbol handling functions
330 FUNCTION
331 bfd_get_symtab_upper_bound
333 DESCRIPTION
334 Return the number of bytes required to store a vector of pointers
335 to <<asymbols>> for all the symbols in the BFD @var{abfd},
336 including a terminal NULL pointer. If there are no symbols in
337 the BFD, then return 0. If an error occurs, return -1.
339 .#define bfd_get_symtab_upper_bound(abfd) \
340 . BFD_SEND (abfd, _bfd_get_symtab_upper_bound, (abfd))
345 FUNCTION
346 bfd_is_local_label
348 SYNOPSIS
349 bfd_boolean bfd_is_local_label(bfd *abfd, asymbol *sym);
351 DESCRIPTION
352 Return TRUE if the given symbol @var{sym} in the BFD @var{abfd} is
353 a compiler generated local label, else return FALSE.
356 bfd_boolean
357 bfd_is_local_label (abfd, sym)
358 bfd *abfd;
359 asymbol *sym;
361 /* The BSF_SECTION_SYM check is needed for IA-64, where every label that
362 starts with '.' is local. This would accidentally catch section names
363 if we didn't reject them here. */
364 if ((sym->flags & (BSF_GLOBAL | BSF_WEAK | BSF_SECTION_SYM)) != 0)
365 return FALSE;
366 if (sym->name == NULL)
367 return FALSE;
368 return bfd_is_local_label_name (abfd, sym->name);
372 FUNCTION
373 bfd_is_local_label_name
375 SYNOPSIS
376 bfd_boolean bfd_is_local_label_name (bfd *abfd, const char *name);
378 DESCRIPTION
379 Return TRUE if a symbol with the name @var{name} in the BFD
380 @var{abfd} is a compiler generated local label, else return
381 FALSE. This just checks whether the name has the form of a
382 local label.
384 .#define bfd_is_local_label_name(abfd, name) \
385 . BFD_SEND (abfd, _bfd_is_local_label_name, (abfd, name))
390 FUNCTION
391 bfd_canonicalize_symtab
393 DESCRIPTION
394 Read the symbols from the BFD @var{abfd}, and fills in
395 the vector @var{location} with pointers to the symbols and
396 a trailing NULL.
397 Return the actual number of symbol pointers, not
398 including the NULL.
400 .#define bfd_canonicalize_symtab(abfd, location) \
401 . BFD_SEND (abfd, _bfd_canonicalize_symtab,\
402 . (abfd, location))
407 FUNCTION
408 bfd_set_symtab
410 SYNOPSIS
411 bfd_boolean bfd_set_symtab (bfd *abfd, asymbol **location, unsigned int count);
413 DESCRIPTION
414 Arrange that when the output BFD @var{abfd} is closed,
415 the table @var{location} of @var{count} pointers to symbols
416 will be written.
419 bfd_boolean
420 bfd_set_symtab (abfd, location, symcount)
421 bfd *abfd;
422 asymbol **location;
423 unsigned int symcount;
425 if ((abfd->format != bfd_object) || (bfd_read_p (abfd)))
427 bfd_set_error (bfd_error_invalid_operation);
428 return FALSE;
431 bfd_get_outsymbols (abfd) = location;
432 bfd_get_symcount (abfd) = symcount;
433 return TRUE;
437 FUNCTION
438 bfd_print_symbol_vandf
440 SYNOPSIS
441 void bfd_print_symbol_vandf(bfd *abfd, PTR file, asymbol *symbol);
443 DESCRIPTION
444 Print the value and flags of the @var{symbol} supplied to the
445 stream @var{file}.
447 void
448 bfd_print_symbol_vandf (abfd, arg, symbol)
449 bfd *abfd;
450 PTR arg;
451 asymbol *symbol;
453 FILE *file = (FILE *) arg;
454 flagword type = symbol->flags;
455 if (symbol->section != (asection *) NULL)
457 bfd_fprintf_vma (abfd, file,
458 symbol->value + symbol->section->vma);
460 else
462 bfd_fprintf_vma (abfd, file, symbol->value);
465 /* This presumes that a symbol can not be both BSF_DEBUGGING and
466 BSF_DYNAMIC, nor more than one of BSF_FUNCTION, BSF_FILE, and
467 BSF_OBJECT. */
468 fprintf (file, " %c%c%c%c%c%c%c",
469 ((type & BSF_LOCAL)
470 ? (type & BSF_GLOBAL) ? '!' : 'l'
471 : (type & BSF_GLOBAL) ? 'g' : ' '),
472 (type & BSF_WEAK) ? 'w' : ' ',
473 (type & BSF_CONSTRUCTOR) ? 'C' : ' ',
474 (type & BSF_WARNING) ? 'W' : ' ',
475 (type & BSF_INDIRECT) ? 'I' : ' ',
476 (type & BSF_DEBUGGING) ? 'd' : (type & BSF_DYNAMIC) ? 'D' : ' ',
477 ((type & BSF_FUNCTION)
478 ? 'F'
479 : ((type & BSF_FILE)
480 ? 'f'
481 : ((type & BSF_OBJECT) ? 'O' : ' '))));
485 FUNCTION
486 bfd_make_empty_symbol
488 DESCRIPTION
489 Create a new <<asymbol>> structure for the BFD @var{abfd}
490 and return a pointer to it.
492 This routine is necessary because each back end has private
493 information surrounding the <<asymbol>>. Building your own
494 <<asymbol>> and pointing to it will not create the private
495 information, and will cause problems later on.
497 .#define bfd_make_empty_symbol(abfd) \
498 . BFD_SEND (abfd, _bfd_make_empty_symbol, (abfd))
503 FUNCTION
504 _bfd_generic_make_empty_symbol
506 SYNOPSIS
507 asymbol *_bfd_generic_make_empty_symbol (bfd *);
509 DESCRIPTION
510 Create a new <<asymbol>> structure for the BFD @var{abfd}
511 and return a pointer to it. Used by core file routines,
512 binary back-end and anywhere else where no private info
513 is needed.
516 asymbol *
517 _bfd_generic_make_empty_symbol (abfd)
518 bfd *abfd;
520 bfd_size_type amt = sizeof (asymbol);
521 asymbol *new = (asymbol *) bfd_zalloc (abfd, amt);
522 if (new)
523 new->the_bfd = abfd;
524 return new;
528 FUNCTION
529 bfd_make_debug_symbol
531 DESCRIPTION
532 Create a new <<asymbol>> structure for the BFD @var{abfd},
533 to be used as a debugging symbol. Further details of its use have
534 yet to be worked out.
536 .#define bfd_make_debug_symbol(abfd,ptr,size) \
537 . BFD_SEND (abfd, _bfd_make_debug_symbol, (abfd, ptr, size))
541 struct section_to_type
543 const char *section;
544 char type;
547 /* Map section names to POSIX/BSD single-character symbol types.
548 This table is probably incomplete. It is sorted for convenience of
549 adding entries. Since it is so short, a linear search is used. */
550 static const struct section_to_type stt[] =
552 {".bss", 'b'},
553 {"code", 't'}, /* MRI .text */
554 {".data", 'd'},
555 {"*DEBUG*", 'N'},
556 {".debug", 'N'}, /* MSVC's .debug (non-standard debug syms) */
557 {".drectve", 'i'}, /* MSVC's .drective section */
558 {".edata", 'e'}, /* MSVC's .edata (export) section */
559 {".fini", 't'}, /* ELF fini section */
560 {".idata", 'i'}, /* MSVC's .idata (import) section */
561 {".init", 't'}, /* ELF init section */
562 {".pdata", 'p'}, /* MSVC's .pdata (stack unwind) section */
563 {".rdata", 'r'}, /* Read only data. */
564 {".rodata", 'r'}, /* Read only data. */
565 {".sbss", 's'}, /* Small BSS (uninitialized data). */
566 {".scommon", 'c'}, /* Small common. */
567 {".sdata", 'g'}, /* Small initialized data. */
568 {".text", 't'},
569 {"vars", 'd'}, /* MRI .data */
570 {"zerovars", 'b'}, /* MRI .bss */
571 {0, 0}
574 /* Return the single-character symbol type corresponding to
575 section S, or '?' for an unknown COFF section.
577 Check for any leading string which matches, so .text5 returns
578 't' as well as .text */
580 static char
581 coff_section_type (s)
582 const char *s;
584 const struct section_to_type *t;
586 for (t = &stt[0]; t->section; t++)
587 if (!strncmp (s, t->section, strlen (t->section)))
588 return t->type;
590 return '?';
593 /* Return the single-character symbol type corresponding to section
594 SECTION, or '?' for an unknown section. This uses section flags to
595 identify sections.
597 FIXME These types are unhandled: c, i, e, p. If we handled these also,
598 we could perhaps obsolete coff_section_type. */
600 static char
601 decode_section_type (section)
602 const struct sec *section;
604 if (section->flags & SEC_CODE)
605 return 't';
606 if (section->flags & SEC_DATA)
608 if (section->flags & SEC_READONLY)
609 return 'r';
610 else if (section->flags & SEC_SMALL_DATA)
611 return 'g';
612 else
613 return 'd';
615 if ((section->flags & SEC_HAS_CONTENTS) == 0)
617 if (section->flags & SEC_SMALL_DATA)
618 return 's';
619 else
620 return 'b';
622 if (section->flags & SEC_DEBUGGING)
623 return 'N';
625 return '?';
629 FUNCTION
630 bfd_decode_symclass
632 DESCRIPTION
633 Return a character corresponding to the symbol
634 class of @var{symbol}, or '?' for an unknown class.
636 SYNOPSIS
637 int bfd_decode_symclass(asymbol *symbol);
640 bfd_decode_symclass (symbol)
641 asymbol *symbol;
643 char c;
645 if (bfd_is_com_section (symbol->section))
646 return 'C';
647 if (bfd_is_und_section (symbol->section))
649 if (symbol->flags & BSF_WEAK)
651 /* If weak, determine if it's specifically an object
652 or non-object weak. */
653 if (symbol->flags & BSF_OBJECT)
654 return 'v';
655 else
656 return 'w';
658 else
659 return 'U';
661 if (bfd_is_ind_section (symbol->section))
662 return 'I';
663 if (symbol->flags & BSF_WEAK)
665 /* If weak, determine if it's specifically an object
666 or non-object weak. */
667 if (symbol->flags & BSF_OBJECT)
668 return 'V';
669 else
670 return 'W';
672 if (!(symbol->flags & (BSF_GLOBAL | BSF_LOCAL)))
673 return '?';
675 if (bfd_is_abs_section (symbol->section))
676 c = 'a';
677 else if (symbol->section)
679 c = coff_section_type (symbol->section->name);
680 if (c == '?')
681 c = decode_section_type (symbol->section);
683 else
684 return '?';
685 if (symbol->flags & BSF_GLOBAL)
686 c = TOUPPER (c);
687 return c;
689 /* We don't have to handle these cases just yet, but we will soon:
690 N_SETV: 'v';
691 N_SETA: 'l';
692 N_SETT: 'x';
693 N_SETD: 'z';
694 N_SETB: 's';
695 N_INDR: 'i';
700 FUNCTION
701 bfd_is_undefined_symclass
703 DESCRIPTION
704 Returns non-zero if the class symbol returned by
705 bfd_decode_symclass represents an undefined symbol.
706 Returns zero otherwise.
708 SYNOPSIS
709 bfd_boolean bfd_is_undefined_symclass (int symclass);
712 bfd_boolean
713 bfd_is_undefined_symclass (symclass)
714 int symclass;
716 return symclass == 'U' || symclass == 'w' || symclass == 'v';
720 FUNCTION
721 bfd_symbol_info
723 DESCRIPTION
724 Fill in the basic info about symbol that nm needs.
725 Additional info may be added by the back-ends after
726 calling this function.
728 SYNOPSIS
729 void bfd_symbol_info(asymbol *symbol, symbol_info *ret);
732 void
733 bfd_symbol_info (symbol, ret)
734 asymbol *symbol;
735 symbol_info *ret;
737 ret->type = bfd_decode_symclass (symbol);
739 if (bfd_is_undefined_symclass (ret->type))
740 ret->value = 0;
741 else
742 ret->value = symbol->value + symbol->section->vma;
744 ret->name = symbol->name;
748 FUNCTION
749 bfd_copy_private_symbol_data
751 SYNOPSIS
752 bfd_boolean bfd_copy_private_symbol_data(bfd *ibfd, asymbol *isym, bfd *obfd, asymbol *osym);
754 DESCRIPTION
755 Copy private symbol information from @var{isym} in the BFD
756 @var{ibfd} to the symbol @var{osym} in the BFD @var{obfd}.
757 Return <<TRUE>> on success, <<FALSE>> on error. Possible error
758 returns are:
760 o <<bfd_error_no_memory>> -
761 Not enough memory exists to create private data for @var{osec}.
763 .#define bfd_copy_private_symbol_data(ibfd, isymbol, obfd, osymbol) \
764 . BFD_SEND (obfd, _bfd_copy_private_symbol_data, \
765 . (ibfd, isymbol, obfd, osymbol))
769 /* The generic version of the function which returns mini symbols.
770 This is used when the backend does not provide a more efficient
771 version. It just uses BFD asymbol structures as mini symbols. */
773 long
774 _bfd_generic_read_minisymbols (abfd, dynamic, minisymsp, sizep)
775 bfd *abfd;
776 bfd_boolean dynamic;
777 PTR *minisymsp;
778 unsigned int *sizep;
780 long storage;
781 asymbol **syms = NULL;
782 long symcount;
784 if (dynamic)
785 storage = bfd_get_dynamic_symtab_upper_bound (abfd);
786 else
787 storage = bfd_get_symtab_upper_bound (abfd);
788 if (storage < 0)
789 goto error_return;
790 if (storage == 0)
791 return 0;
793 syms = (asymbol **) bfd_malloc ((bfd_size_type) storage);
794 if (syms == NULL)
795 goto error_return;
797 if (dynamic)
798 symcount = bfd_canonicalize_dynamic_symtab (abfd, syms);
799 else
800 symcount = bfd_canonicalize_symtab (abfd, syms);
801 if (symcount < 0)
802 goto error_return;
804 *minisymsp = (PTR) syms;
805 *sizep = sizeof (asymbol *);
806 return symcount;
808 error_return:
809 bfd_set_error (bfd_error_no_symbols);
810 if (syms != NULL)
811 free (syms);
812 return -1;
815 /* The generic version of the function which converts a minisymbol to
816 an asymbol. We don't worry about the sym argument we are passed;
817 we just return the asymbol the minisymbol points to. */
819 /*ARGSUSED*/
820 asymbol *
821 _bfd_generic_minisymbol_to_symbol (abfd, dynamic, minisym, sym)
822 bfd *abfd ATTRIBUTE_UNUSED;
823 bfd_boolean dynamic ATTRIBUTE_UNUSED;
824 const PTR minisym;
825 asymbol *sym ATTRIBUTE_UNUSED;
827 return *(asymbol **) minisym;
830 /* Look through stabs debugging information in .stab and .stabstr
831 sections to find the source file and line closest to a desired
832 location. This is used by COFF and ELF targets. It sets *pfound
833 to TRUE if it finds some information. The *pinfo field is used to
834 pass cached information in and out of this routine; this first time
835 the routine is called for a BFD, *pinfo should be NULL. The value
836 placed in *pinfo should be saved with the BFD, and passed back each
837 time this function is called. */
839 /* We use a cache by default. */
841 #define ENABLE_CACHING
843 /* We keep an array of indexentry structures to record where in the
844 stabs section we should look to find line number information for a
845 particular address. */
847 struct indexentry
849 bfd_vma val;
850 bfd_byte *stab;
851 bfd_byte *str;
852 char *directory_name;
853 char *file_name;
854 char *function_name;
857 /* Compare two indexentry structures. This is called via qsort. */
859 static int
860 cmpindexentry (a, b)
861 const PTR a;
862 const PTR b;
864 const struct indexentry *contestantA = (const struct indexentry *) a;
865 const struct indexentry *contestantB = (const struct indexentry *) b;
867 if (contestantA->val < contestantB->val)
868 return -1;
869 else if (contestantA->val > contestantB->val)
870 return 1;
871 else
872 return 0;
875 /* A pointer to this structure is stored in *pinfo. */
877 struct stab_find_info
879 /* The .stab section. */
880 asection *stabsec;
881 /* The .stabstr section. */
882 asection *strsec;
883 /* The contents of the .stab section. */
884 bfd_byte *stabs;
885 /* The contents of the .stabstr section. */
886 bfd_byte *strs;
888 /* A table that indexes stabs by memory address. */
889 struct indexentry *indextable;
890 /* The number of entries in indextable. */
891 int indextablesize;
893 #ifdef ENABLE_CACHING
894 /* Cached values to restart quickly. */
895 struct indexentry *cached_indexentry;
896 bfd_vma cached_offset;
897 bfd_byte *cached_stab;
898 char *cached_file_name;
899 #endif
901 /* Saved ptr to malloc'ed filename. */
902 char *filename;
905 bfd_boolean
906 _bfd_stab_section_find_nearest_line (abfd, symbols, section, offset, pfound,
907 pfilename, pfnname, pline, pinfo)
908 bfd *abfd;
909 asymbol **symbols;
910 asection *section;
911 bfd_vma offset;
912 bfd_boolean *pfound;
913 const char **pfilename;
914 const char **pfnname;
915 unsigned int *pline;
916 PTR *pinfo;
918 struct stab_find_info *info;
919 bfd_size_type stabsize, strsize;
920 bfd_byte *stab, *str;
921 bfd_byte *last_stab = NULL;
922 bfd_size_type stroff;
923 struct indexentry *indexentry;
924 char *file_name;
925 char *directory_name;
926 int saw_fun;
927 bfd_boolean saw_line, saw_func;
929 *pfound = FALSE;
930 *pfilename = bfd_get_filename (abfd);
931 *pfnname = NULL;
932 *pline = 0;
934 /* Stabs entries use a 12 byte format:
935 4 byte string table index
936 1 byte stab type
937 1 byte stab other field
938 2 byte stab desc field
939 4 byte stab value
940 FIXME: This will have to change for a 64 bit object format.
942 The stabs symbols are divided into compilation units. For the
943 first entry in each unit, the type of 0, the value is the length
944 of the string table for this unit, and the desc field is the
945 number of stabs symbols for this unit. */
947 #define STRDXOFF (0)
948 #define TYPEOFF (4)
949 #define OTHEROFF (5)
950 #define DESCOFF (6)
951 #define VALOFF (8)
952 #define STABSIZE (12)
954 info = (struct stab_find_info *) *pinfo;
955 if (info != NULL)
957 if (info->stabsec == NULL || info->strsec == NULL)
959 /* No stabs debugging information. */
960 return TRUE;
963 stabsize = info->stabsec->_raw_size;
964 strsize = info->strsec->_raw_size;
966 else
968 long reloc_size, reloc_count;
969 arelent **reloc_vector;
970 int i;
971 char *name;
972 char *function_name;
973 bfd_size_type amt = sizeof *info;
975 info = (struct stab_find_info *) bfd_zalloc (abfd, amt);
976 if (info == NULL)
977 return FALSE;
979 /* FIXME: When using the linker --split-by-file or
980 --split-by-reloc options, it is possible for the .stab and
981 .stabstr sections to be split. We should handle that. */
983 info->stabsec = bfd_get_section_by_name (abfd, ".stab");
984 info->strsec = bfd_get_section_by_name (abfd, ".stabstr");
986 if (info->stabsec == NULL || info->strsec == NULL)
988 /* No stabs debugging information. Set *pinfo so that we
989 can return quickly in the info != NULL case above. */
990 *pinfo = (PTR) info;
991 return TRUE;
994 stabsize = info->stabsec->_raw_size;
995 strsize = info->strsec->_raw_size;
997 info->stabs = (bfd_byte *) bfd_alloc (abfd, stabsize);
998 info->strs = (bfd_byte *) bfd_alloc (abfd, strsize);
999 if (info->stabs == NULL || info->strs == NULL)
1000 return FALSE;
1002 if (! bfd_get_section_contents (abfd, info->stabsec, info->stabs,
1003 (bfd_vma) 0, stabsize)
1004 || ! bfd_get_section_contents (abfd, info->strsec, info->strs,
1005 (bfd_vma) 0, strsize))
1006 return FALSE;
1008 /* If this is a relocateable object file, we have to relocate
1009 the entries in .stab. This should always be simple 32 bit
1010 relocations against symbols defined in this object file, so
1011 this should be no big deal. */
1012 reloc_size = bfd_get_reloc_upper_bound (abfd, info->stabsec);
1013 if (reloc_size < 0)
1014 return FALSE;
1015 reloc_vector = (arelent **) bfd_malloc ((bfd_size_type) reloc_size);
1016 if (reloc_vector == NULL && reloc_size != 0)
1017 return FALSE;
1018 reloc_count = bfd_canonicalize_reloc (abfd, info->stabsec, reloc_vector,
1019 symbols);
1020 if (reloc_count < 0)
1022 if (reloc_vector != NULL)
1023 free (reloc_vector);
1024 return FALSE;
1026 if (reloc_count > 0)
1028 arelent **pr;
1030 for (pr = reloc_vector; *pr != NULL; pr++)
1032 arelent *r;
1033 unsigned long val;
1034 asymbol *sym;
1036 r = *pr;
1037 if (r->howto->rightshift != 0
1038 || r->howto->size != 2
1039 || r->howto->bitsize != 32
1040 || r->howto->pc_relative
1041 || r->howto->bitpos != 0
1042 || r->howto->dst_mask != 0xffffffff)
1044 (*_bfd_error_handler)
1045 (_("Unsupported .stab relocation"));
1046 bfd_set_error (bfd_error_invalid_operation);
1047 if (reloc_vector != NULL)
1048 free (reloc_vector);
1049 return FALSE;
1052 val = bfd_get_32 (abfd, info->stabs + r->address);
1053 val &= r->howto->src_mask;
1054 sym = *r->sym_ptr_ptr;
1055 val += sym->value + sym->section->vma + r->addend;
1056 bfd_put_32 (abfd, (bfd_vma) val, info->stabs + r->address);
1060 if (reloc_vector != NULL)
1061 free (reloc_vector);
1063 /* First time through this function, build a table matching
1064 function VM addresses to stabs, then sort based on starting
1065 VM address. Do this in two passes: once to count how many
1066 table entries we'll need, and a second to actually build the
1067 table. */
1069 info->indextablesize = 0;
1070 saw_fun = 1;
1071 for (stab = info->stabs; stab < info->stabs + stabsize; stab += STABSIZE)
1073 if (stab[TYPEOFF] == (bfd_byte) N_SO)
1075 /* N_SO with null name indicates EOF */
1076 if (bfd_get_32 (abfd, stab + STRDXOFF) == 0)
1077 continue;
1079 /* if we did not see a function def, leave space for one. */
1080 if (saw_fun == 0)
1081 ++info->indextablesize;
1083 saw_fun = 0;
1085 /* two N_SO's in a row is a filename and directory. Skip */
1086 if (stab + STABSIZE < info->stabs + stabsize
1087 && *(stab + STABSIZE + TYPEOFF) == (bfd_byte) N_SO)
1089 stab += STABSIZE;
1092 else if (stab[TYPEOFF] == (bfd_byte) N_FUN)
1094 saw_fun = 1;
1095 ++info->indextablesize;
1099 if (saw_fun == 0)
1100 ++info->indextablesize;
1102 if (info->indextablesize == 0)
1103 return TRUE;
1104 ++info->indextablesize;
1106 amt = info->indextablesize;
1107 amt *= sizeof (struct indexentry);
1108 info->indextable = (struct indexentry *) bfd_alloc (abfd, amt);
1109 if (info->indextable == NULL)
1110 return FALSE;
1112 file_name = NULL;
1113 directory_name = NULL;
1114 saw_fun = 1;
1116 for (i = 0, stroff = 0, stab = info->stabs, str = info->strs;
1117 i < info->indextablesize && stab < info->stabs + stabsize;
1118 stab += STABSIZE)
1120 switch (stab[TYPEOFF])
1122 case 0:
1123 /* This is the first entry in a compilation unit. */
1124 if ((bfd_size_type) ((info->strs + strsize) - str) < stroff)
1125 break;
1126 str += stroff;
1127 stroff = bfd_get_32 (abfd, stab + VALOFF);
1128 break;
1130 case N_SO:
1131 /* The main file name. */
1133 /* The following code creates a new indextable entry with
1134 a NULL function name if there were no N_FUNs in a file.
1135 Note that a N_SO without a file name is an EOF and
1136 there could be 2 N_SO following it with the new filename
1137 and directory. */
1138 if (saw_fun == 0)
1140 info->indextable[i].val = bfd_get_32 (abfd, last_stab + VALOFF);
1141 info->indextable[i].stab = last_stab;
1142 info->indextable[i].str = str;
1143 info->indextable[i].directory_name = directory_name;
1144 info->indextable[i].file_name = file_name;
1145 info->indextable[i].function_name = NULL;
1146 ++i;
1148 saw_fun = 0;
1150 file_name = (char *) str + bfd_get_32 (abfd, stab + STRDXOFF);
1151 if (*file_name == '\0')
1153 directory_name = NULL;
1154 file_name = NULL;
1155 saw_fun = 1;
1157 else
1159 last_stab = stab;
1160 if (stab + STABSIZE >= info->stabs + stabsize
1161 || *(stab + STABSIZE + TYPEOFF) != (bfd_byte) N_SO)
1163 directory_name = NULL;
1165 else
1167 /* Two consecutive N_SOs are a directory and a
1168 file name. */
1169 stab += STABSIZE;
1170 directory_name = file_name;
1171 file_name = ((char *) str
1172 + bfd_get_32 (abfd, stab + STRDXOFF));
1175 break;
1177 case N_SOL:
1178 /* The name of an include file. */
1179 file_name = (char *) str + bfd_get_32 (abfd, stab + STRDXOFF);
1180 break;
1182 case N_FUN:
1183 /* A function name. */
1184 saw_fun = 1;
1185 name = (char *) str + bfd_get_32 (abfd, stab + STRDXOFF);
1187 if (*name == '\0')
1188 name = NULL;
1190 function_name = name;
1192 if (name == NULL)
1193 continue;
1195 info->indextable[i].val = bfd_get_32 (abfd, stab + VALOFF);
1196 info->indextable[i].stab = stab;
1197 info->indextable[i].str = str;
1198 info->indextable[i].directory_name = directory_name;
1199 info->indextable[i].file_name = file_name;
1200 info->indextable[i].function_name = function_name;
1201 ++i;
1202 break;
1206 if (saw_fun == 0)
1208 info->indextable[i].val = bfd_get_32 (abfd, last_stab + VALOFF);
1209 info->indextable[i].stab = last_stab;
1210 info->indextable[i].str = str;
1211 info->indextable[i].directory_name = directory_name;
1212 info->indextable[i].file_name = file_name;
1213 info->indextable[i].function_name = NULL;
1214 ++i;
1217 info->indextable[i].val = (bfd_vma) -1;
1218 info->indextable[i].stab = info->stabs + stabsize;
1219 info->indextable[i].str = str;
1220 info->indextable[i].directory_name = NULL;
1221 info->indextable[i].file_name = NULL;
1222 info->indextable[i].function_name = NULL;
1223 ++i;
1225 info->indextablesize = i;
1226 qsort (info->indextable, (size_t) i, sizeof (struct indexentry),
1227 cmpindexentry);
1229 *pinfo = (PTR) info;
1232 /* We are passed a section relative offset. The offsets in the
1233 stabs information are absolute. */
1234 offset += bfd_get_section_vma (abfd, section);
1236 #ifdef ENABLE_CACHING
1237 if (info->cached_indexentry != NULL
1238 && offset >= info->cached_offset
1239 && offset < (info->cached_indexentry + 1)->val)
1241 stab = info->cached_stab;
1242 indexentry = info->cached_indexentry;
1243 file_name = info->cached_file_name;
1245 else
1246 #endif
1248 /* Cache non-existant or invalid. Do binary search on
1249 indextable. */
1251 long low, high;
1252 long mid = -1;
1254 indexentry = NULL;
1256 low = 0;
1257 high = info->indextablesize - 1;
1258 while (low != high)
1260 mid = (high + low) / 2;
1261 if (offset >= info->indextable[mid].val
1262 && offset < info->indextable[mid + 1].val)
1264 indexentry = &info->indextable[mid];
1265 break;
1268 if (info->indextable[mid].val > offset)
1269 high = mid;
1270 else
1271 low = mid + 1;
1274 if (indexentry == NULL)
1275 return TRUE;
1277 stab = indexentry->stab + STABSIZE;
1278 file_name = indexentry->file_name;
1281 directory_name = indexentry->directory_name;
1282 str = indexentry->str;
1284 saw_line = FALSE;
1285 saw_func = FALSE;
1286 for (; stab < (indexentry+1)->stab; stab += STABSIZE)
1288 bfd_boolean done;
1289 bfd_vma val;
1291 done = FALSE;
1293 switch (stab[TYPEOFF])
1295 case N_SOL:
1296 /* The name of an include file. */
1297 val = bfd_get_32 (abfd, stab + VALOFF);
1298 if (val <= offset)
1300 file_name = (char *) str + bfd_get_32 (abfd, stab + STRDXOFF);
1301 *pline = 0;
1303 break;
1305 case N_SLINE:
1306 case N_DSLINE:
1307 case N_BSLINE:
1308 /* A line number. The value is relative to the start of the
1309 current function. */
1310 val = indexentry->val + bfd_get_32 (abfd, stab + VALOFF);
1311 /* If this line starts before our desired offset, or if it's
1312 the first line we've been able to find, use it. The
1313 !saw_line check works around a bug in GCC 2.95.3, which emits
1314 the first N_SLINE late. */
1315 if (!saw_line || val <= offset)
1317 *pline = bfd_get_16 (abfd, stab + DESCOFF);
1319 #ifdef ENABLE_CACHING
1320 info->cached_stab = stab;
1321 info->cached_offset = val;
1322 info->cached_file_name = file_name;
1323 info->cached_indexentry = indexentry;
1324 #endif
1326 if (val > offset)
1327 done = TRUE;
1328 saw_line = TRUE;
1329 break;
1331 case N_FUN:
1332 case N_SO:
1333 if (saw_func || saw_line)
1334 done = TRUE;
1335 saw_func = TRUE;
1336 break;
1339 if (done)
1340 break;
1343 *pfound = TRUE;
1345 if (file_name == NULL || IS_ABSOLUTE_PATH (file_name)
1346 || directory_name == NULL)
1347 *pfilename = file_name;
1348 else
1350 size_t dirlen;
1352 dirlen = strlen (directory_name);
1353 if (info->filename == NULL
1354 || strncmp (info->filename, directory_name, dirlen) != 0
1355 || strcmp (info->filename + dirlen, file_name) != 0)
1357 size_t len;
1359 if (info->filename != NULL)
1360 free (info->filename);
1361 len = strlen (file_name) + 1;
1362 info->filename = (char *) bfd_malloc ((bfd_size_type) dirlen + len);
1363 if (info->filename == NULL)
1364 return FALSE;
1365 memcpy (info->filename, directory_name, dirlen);
1366 memcpy (info->filename + dirlen, file_name, len);
1369 *pfilename = info->filename;
1372 if (indexentry->function_name != NULL)
1374 char *s;
1376 /* This will typically be something like main:F(0,1), so we want
1377 to clobber the colon. It's OK to change the name, since the
1378 string is in our own local storage anyhow. */
1380 s = strchr (indexentry->function_name, ':');
1381 if (s != NULL)
1382 *s = '\0';
1384 *pfnname = indexentry->function_name;
1387 return TRUE;