]> git.ipfire.org Git - thirdparty/binutils-gdb.git/blob - gdb/elfread.c
2003-01-21 Andrew Cagney <ac131313@redhat.com>
[thirdparty/binutils-gdb.git] / gdb / elfread.c
1 /* Read ELF (Executable and Linking Format) object files for GDB.
2
3 Copyright 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
4 2000, 2001, 2002, 2003 Free Software Foundation, Inc.
5
6 Written by Fred Fish at Cygnus Support.
7
8 This file is part of GDB.
9
10 This program is free software; you can redistribute it and/or modify
11 it under the terms of the GNU General Public License as published by
12 the Free Software Foundation; either version 2 of the License, or
13 (at your option) any later version.
14
15 This program is distributed in the hope that it will be useful,
16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 GNU General Public License for more details.
19
20 You should have received a copy of the GNU General Public License
21 along with this program; if not, write to the Free Software
22 Foundation, Inc., 59 Temple Place - Suite 330,
23 Boston, MA 02111-1307, USA. */
24
25 #include "defs.h"
26 #include "bfd.h"
27 #include "gdb_string.h"
28 #include "elf-bfd.h"
29 #include "elf/mips.h"
30 #include "symtab.h"
31 #include "symfile.h"
32 #include "objfiles.h"
33 #include "buildsym.h"
34 #include "stabsread.h"
35 #include "gdb-stabs.h"
36 #include "complaints.h"
37 #include "demangle.h"
38
39 extern void _initialize_elfread (void);
40
41 /* The struct elfinfo is available only during ELF symbol table and
42 psymtab reading. It is destroyed at the completion of psymtab-reading.
43 It's local to elf_symfile_read. */
44
45 struct elfinfo
46 {
47 file_ptr dboffset; /* Offset to dwarf debug section */
48 unsigned int dbsize; /* Size of dwarf debug section */
49 file_ptr lnoffset; /* Offset to dwarf line number section */
50 unsigned int lnsize; /* Size of dwarf line number section */
51 asection *stabsect; /* Section pointer for .stab section */
52 asection *stabindexsect; /* Section pointer for .stab.index section */
53 asection *mdebugsect; /* Section pointer for .mdebug section */
54 };
55
56 static void free_elfinfo (void *);
57
58 /* We are called once per section from elf_symfile_read. We
59 need to examine each section we are passed, check to see
60 if it is something we are interested in processing, and
61 if so, stash away some access information for the section.
62
63 For now we recognize the dwarf debug information sections and
64 line number sections from matching their section names. The
65 ELF definition is no real help here since it has no direct
66 knowledge of DWARF (by design, so any debugging format can be
67 used).
68
69 We also recognize the ".stab" sections used by the Sun compilers
70 released with Solaris 2.
71
72 FIXME: The section names should not be hardwired strings (what
73 should they be? I don't think most object file formats have enough
74 section flags to specify what kind of debug section it is
75 -kingdon). */
76
77 static void
78 elf_locate_sections (bfd *ignore_abfd, asection *sectp, void *eip)
79 {
80 register struct elfinfo *ei;
81
82 ei = (struct elfinfo *) eip;
83 if (STREQ (sectp->name, ".debug"))
84 {
85 ei->dboffset = sectp->filepos;
86 ei->dbsize = bfd_get_section_size_before_reloc (sectp);
87 }
88 else if (STREQ (sectp->name, ".line"))
89 {
90 ei->lnoffset = sectp->filepos;
91 ei->lnsize = bfd_get_section_size_before_reloc (sectp);
92 }
93 else if (STREQ (sectp->name, ".stab"))
94 {
95 ei->stabsect = sectp;
96 }
97 else if (STREQ (sectp->name, ".stab.index"))
98 {
99 ei->stabindexsect = sectp;
100 }
101 else if (STREQ (sectp->name, ".mdebug"))
102 {
103 ei->mdebugsect = sectp;
104 }
105 }
106
107 #if 0 /* Currently unused */
108
109 char *
110 elf_interpreter (bfd *abfd)
111 {
112 sec_ptr interp_sec;
113 unsigned size;
114 char *interp = NULL;
115
116 interp_sec = bfd_get_section_by_name (abfd, ".interp");
117 if (interp_sec)
118 {
119 size = bfd_section_size (abfd, interp_sec);
120 interp = alloca (size);
121 if (bfd_get_section_contents (abfd, interp_sec, interp, (file_ptr) 0,
122 size))
123 {
124 interp = savestring (interp, size - 1);
125 }
126 else
127 {
128 interp = NULL;
129 }
130 }
131 return (interp);
132 }
133
134 #endif
135
136 static struct minimal_symbol *
137 record_minimal_symbol_and_info (char *name, CORE_ADDR address,
138 enum minimal_symbol_type ms_type, char *info, /* FIXME, is this really char *? */
139 asection *bfd_section, struct objfile *objfile)
140 {
141 if (ms_type == mst_text || ms_type == mst_file_text)
142 address = SMASH_TEXT_ADDRESS (address);
143
144 return prim_record_minimal_symbol_and_info
145 (name, address, ms_type, info, bfd_section->index, bfd_section, objfile);
146 }
147
148 /*
149
150 LOCAL FUNCTION
151
152 elf_symtab_read -- read the symbol table of an ELF file
153
154 SYNOPSIS
155
156 void elf_symtab_read (struct objfile *objfile, int dynamic)
157
158 DESCRIPTION
159
160 Given an objfile and a flag that specifies whether or not the objfile
161 is for an executable or not (may be shared library for example), add
162 all the global function and data symbols to the minimal symbol table.
163
164 In stabs-in-ELF, as implemented by Sun, there are some local symbols
165 defined in the ELF symbol table, which can be used to locate
166 the beginnings of sections from each ".o" file that was linked to
167 form the executable objfile. We gather any such info and record it
168 in data structures hung off the objfile's private data.
169
170 */
171
172 static void
173 elf_symtab_read (struct objfile *objfile, int dynamic)
174 {
175 long storage_needed;
176 asymbol *sym;
177 asymbol **symbol_table;
178 long number_of_symbols;
179 long i;
180 int index;
181 struct cleanup *back_to;
182 CORE_ADDR symaddr;
183 CORE_ADDR offset;
184 enum minimal_symbol_type ms_type;
185 /* If sectinfo is nonNULL, it contains section info that should end up
186 filed in the objfile. */
187 struct stab_section_info *sectinfo = NULL;
188 /* If filesym is nonzero, it points to a file symbol, but we haven't
189 seen any section info for it yet. */
190 asymbol *filesym = 0;
191 #ifdef SOFUN_ADDRESS_MAYBE_MISSING
192 /* Name of filesym, as saved on the symbol_obstack. */
193 char *filesymname = obsavestring ("", 0, &objfile->symbol_obstack);
194 #endif
195 struct dbx_symfile_info *dbx = objfile->sym_stab_info;
196 unsigned long size;
197 int stripped = (bfd_get_symcount (objfile->obfd) == 0);
198
199 if (dynamic)
200 {
201 storage_needed = bfd_get_dynamic_symtab_upper_bound (objfile->obfd);
202
203 /* Nothing to be done if there is no dynamic symtab. */
204 if (storage_needed < 0)
205 return;
206 }
207 else
208 {
209 storage_needed = bfd_get_symtab_upper_bound (objfile->obfd);
210 if (storage_needed < 0)
211 error ("Can't read symbols from %s: %s", bfd_get_filename (objfile->obfd),
212 bfd_errmsg (bfd_get_error ()));
213 }
214 if (storage_needed > 0)
215 {
216 symbol_table = (asymbol **) xmalloc (storage_needed);
217 back_to = make_cleanup (xfree, symbol_table);
218 if (dynamic)
219 number_of_symbols = bfd_canonicalize_dynamic_symtab (objfile->obfd,
220 symbol_table);
221 else
222 number_of_symbols = bfd_canonicalize_symtab (objfile->obfd, symbol_table);
223 if (number_of_symbols < 0)
224 error ("Can't read symbols from %s: %s", bfd_get_filename (objfile->obfd),
225 bfd_errmsg (bfd_get_error ()));
226
227 for (i = 0; i < number_of_symbols; i++)
228 {
229 sym = symbol_table[i];
230 if (sym->name == NULL || *sym->name == '\0')
231 {
232 /* Skip names that don't exist (shouldn't happen), or names
233 that are null strings (may happen). */
234 continue;
235 }
236
237 offset = ANOFFSET (objfile->section_offsets, sym->section->index);
238 if (dynamic
239 && sym->section == &bfd_und_section
240 && (sym->flags & BSF_FUNCTION))
241 {
242 struct minimal_symbol *msym;
243
244 /* Symbol is a reference to a function defined in
245 a shared library.
246 If its value is non zero then it is usually the address
247 of the corresponding entry in the procedure linkage table,
248 plus the desired section offset.
249 If its value is zero then the dynamic linker has to resolve
250 the symbol. We are unable to find any meaningful address
251 for this symbol in the executable file, so we skip it. */
252 symaddr = sym->value;
253 if (symaddr == 0)
254 continue;
255 symaddr += offset;
256 msym = record_minimal_symbol_and_info
257 ((char *) sym->name, symaddr,
258 mst_solib_trampoline, NULL, sym->section, objfile);
259 #ifdef SOFUN_ADDRESS_MAYBE_MISSING
260 if (msym != NULL)
261 msym->filename = filesymname;
262 #endif
263 continue;
264 }
265
266 /* If it is a nonstripped executable, do not enter dynamic
267 symbols, as the dynamic symbol table is usually a subset
268 of the main symbol table. */
269 if (dynamic && !stripped)
270 continue;
271 if (sym->flags & BSF_FILE)
272 {
273 /* STT_FILE debugging symbol that helps stabs-in-elf debugging.
274 Chain any old one onto the objfile; remember new sym. */
275 if (sectinfo != NULL)
276 {
277 sectinfo->next = dbx->stab_section_info;
278 dbx->stab_section_info = sectinfo;
279 sectinfo = NULL;
280 }
281 filesym = sym;
282 #ifdef SOFUN_ADDRESS_MAYBE_MISSING
283 filesymname =
284 obsavestring ((char *) filesym->name, strlen (filesym->name),
285 &objfile->symbol_obstack);
286 #endif
287 }
288 else if (sym->flags & (BSF_GLOBAL | BSF_LOCAL | BSF_WEAK))
289 {
290 struct minimal_symbol *msym;
291
292 /* Select global/local/weak symbols. Note that bfd puts abs
293 symbols in their own section, so all symbols we are
294 interested in will have a section. */
295 /* Bfd symbols are section relative. */
296 symaddr = sym->value + sym->section->vma;
297 /* Relocate all non-absolute symbols by the section offset. */
298 if (sym->section != &bfd_abs_section)
299 {
300 symaddr += offset;
301 }
302 /* For non-absolute symbols, use the type of the section
303 they are relative to, to intuit text/data. Bfd provides
304 no way of figuring this out for absolute symbols. */
305 if (sym->section == &bfd_abs_section)
306 {
307 /* This is a hack to get the minimal symbol type
308 right for Irix 5, which has absolute addresses
309 with special section indices for dynamic symbols. */
310 unsigned short shndx =
311 ((elf_symbol_type *) sym)->internal_elf_sym.st_shndx;
312
313 switch (shndx)
314 {
315 case SHN_MIPS_TEXT:
316 ms_type = mst_text;
317 break;
318 case SHN_MIPS_DATA:
319 ms_type = mst_data;
320 break;
321 case SHN_MIPS_ACOMMON:
322 ms_type = mst_bss;
323 break;
324 default:
325 ms_type = mst_abs;
326 }
327
328 /* If it is an Irix dynamic symbol, skip section name
329 symbols, relocate all others by section offset. */
330 if (ms_type != mst_abs)
331 {
332 if (sym->name[0] == '.')
333 continue;
334 symaddr += offset;
335 }
336 }
337 else if (sym->section->flags & SEC_CODE)
338 {
339 if (sym->flags & BSF_GLOBAL)
340 {
341 ms_type = mst_text;
342 }
343 else if ((sym->name[0] == '.' && sym->name[1] == 'L')
344 || ((sym->flags & BSF_LOCAL)
345 && sym->name[0] == '$'
346 && sym->name[1] == 'L'))
347 /* Looks like a compiler-generated label. Skip
348 it. The assembler should be skipping these (to
349 keep executables small), but apparently with
350 gcc on the (deleted) delta m88k SVR4, it loses.
351 So to have us check too should be harmless (but
352 I encourage people to fix this in the assembler
353 instead of adding checks here). */
354 continue;
355 else
356 {
357 ms_type = mst_file_text;
358 }
359 }
360 else if (sym->section->flags & SEC_ALLOC)
361 {
362 if (sym->flags & (BSF_GLOBAL | BSF_WEAK))
363 {
364 if (sym->section->flags & SEC_LOAD)
365 {
366 ms_type = mst_data;
367 }
368 else
369 {
370 ms_type = mst_bss;
371 }
372 }
373 else if (sym->flags & BSF_LOCAL)
374 {
375 /* Named Local variable in a Data section. Check its
376 name for stabs-in-elf. The STREQ macro checks the
377 first character inline, so we only actually do a
378 strcmp function call on names that start with 'B'
379 or 'D' */
380 index = SECT_OFF_MAX;
381 if (STREQ ("Bbss.bss", sym->name))
382 {
383 index = SECT_OFF_BSS (objfile);
384 }
385 else if (STREQ ("Ddata.data", sym->name))
386 {
387 index = SECT_OFF_DATA (objfile);
388 }
389 else if (STREQ ("Drodata.rodata", sym->name))
390 {
391 index = SECT_OFF_RODATA (objfile);
392 }
393 if (index != SECT_OFF_MAX)
394 {
395 /* Found a special local symbol. Allocate a
396 sectinfo, if needed, and fill it in. */
397 if (sectinfo == NULL)
398 {
399 sectinfo = (struct stab_section_info *)
400 xmmalloc (objfile->md, sizeof (*sectinfo));
401 memset (sectinfo, 0,
402 sizeof (*sectinfo));
403 if (filesym == NULL)
404 {
405 complaint (&symfile_complaints,
406 "elf/stab section information %s without a preceding file symbol",
407 sym->name);
408 }
409 else
410 {
411 sectinfo->filename =
412 (char *) filesym->name;
413 }
414 }
415 if (index != -1)
416 {
417 if (sectinfo->sections[index] != 0)
418 {
419 complaint (&symfile_complaints,
420 "duplicated elf/stab section information for %s",
421 sectinfo->filename);
422 }
423 }
424 else
425 internal_error (__FILE__, __LINE__,
426 "Section index uninitialized.");
427 /* Bfd symbols are section relative. */
428 symaddr = sym->value + sym->section->vma;
429 /* Relocate non-absolute symbols by the section offset. */
430 if (sym->section != &bfd_abs_section)
431 {
432 symaddr += offset;
433 }
434 if (index != -1)
435 sectinfo->sections[index] = symaddr;
436 else
437 internal_error (__FILE__, __LINE__,
438 "Section index uninitialized.");
439 /* The special local symbols don't go in the
440 minimal symbol table, so ignore this one. */
441 continue;
442 }
443 /* Not a special stabs-in-elf symbol, do regular
444 symbol processing. */
445 if (sym->section->flags & SEC_LOAD)
446 {
447 ms_type = mst_file_data;
448 }
449 else
450 {
451 ms_type = mst_file_bss;
452 }
453 }
454 else
455 {
456 ms_type = mst_unknown;
457 }
458 }
459 else
460 {
461 /* FIXME: Solaris2 shared libraries include lots of
462 odd "absolute" and "undefined" symbols, that play
463 hob with actions like finding what function the PC
464 is in. Ignore them if they aren't text, data, or bss. */
465 /* ms_type = mst_unknown; */
466 continue; /* Skip this symbol. */
467 }
468 /* Pass symbol size field in via BFD. FIXME!!! */
469 size = ((elf_symbol_type *) sym)->internal_elf_sym.st_size;
470 msym = record_minimal_symbol_and_info
471 ((char *) sym->name, symaddr,
472 ms_type, (void *) size, sym->section, objfile);
473 #ifdef SOFUN_ADDRESS_MAYBE_MISSING
474 if (msym != NULL)
475 msym->filename = filesymname;
476 #endif
477 ELF_MAKE_MSYMBOL_SPECIAL (sym, msym);
478 }
479 }
480 do_cleanups (back_to);
481 }
482 }
483
484 /* Scan and build partial symbols for a symbol file.
485 We have been initialized by a call to elf_symfile_init, which
486 currently does nothing.
487
488 SECTION_OFFSETS is a set of offsets to apply to relocate the symbols
489 in each section. We simplify it down to a single offset for all
490 symbols. FIXME.
491
492 MAINLINE is true if we are reading the main symbol
493 table (as opposed to a shared lib or dynamically loaded file).
494
495 This function only does the minimum work necessary for letting the
496 user "name" things symbolically; it does not read the entire symtab.
497 Instead, it reads the external and static symbols and puts them in partial
498 symbol tables. When more extensive information is requested of a
499 file, the corresponding partial symbol table is mutated into a full
500 fledged symbol table by going back and reading the symbols
501 for real.
502
503 We look for sections with specific names, to tell us what debug
504 format to look for: FIXME!!!
505
506 dwarf_build_psymtabs() builds psymtabs for DWARF symbols;
507 elfstab_build_psymtabs() handles STABS symbols;
508 mdebug_build_psymtabs() handles ECOFF debugging information.
509
510 Note that ELF files have a "minimal" symbol table, which looks a lot
511 like a COFF symbol table, but has only the minimal information necessary
512 for linking. We process this also, and use the information to
513 build gdb's minimal symbol table. This gives us some minimal debugging
514 capability even for files compiled without -g. */
515
516 static void
517 elf_symfile_read (struct objfile *objfile, int mainline)
518 {
519 bfd *abfd = objfile->obfd;
520 struct elfinfo ei;
521 struct cleanup *back_to;
522 CORE_ADDR offset;
523
524 init_minimal_symbol_collection ();
525 back_to = make_cleanup_discard_minimal_symbols ();
526
527 memset ((char *) &ei, 0, sizeof (ei));
528
529 /* Allocate struct to keep track of the symfile */
530 objfile->sym_stab_info = (struct dbx_symfile_info *)
531 xmmalloc (objfile->md, sizeof (struct dbx_symfile_info));
532 memset ((char *) objfile->sym_stab_info, 0, sizeof (struct dbx_symfile_info));
533 make_cleanup (free_elfinfo, (void *) objfile);
534
535 /* Process the normal ELF symbol table first. This may write some
536 chain of info into the dbx_symfile_info in objfile->sym_stab_info,
537 which can later be used by elfstab_offset_sections. */
538
539 elf_symtab_read (objfile, 0);
540
541 /* Add the dynamic symbols. */
542
543 elf_symtab_read (objfile, 1);
544
545 /* Now process debugging information, which is contained in
546 special ELF sections. */
547
548 /* If we are reinitializing, or if we have never loaded syms yet,
549 set table to empty. MAINLINE is cleared so that *_read_psymtab
550 functions do not all also re-initialize the psymbol table. */
551 if (mainline)
552 {
553 init_psymbol_list (objfile, 0);
554 mainline = 0;
555 }
556
557 /* We first have to find them... */
558 bfd_map_over_sections (abfd, elf_locate_sections, (void *) & ei);
559
560 /* ELF debugging information is inserted into the psymtab in the
561 order of least informative first - most informative last. Since
562 the psymtab table is searched `most recent insertion first' this
563 increases the probability that more detailed debug information
564 for a section is found.
565
566 For instance, an object file might contain both .mdebug (XCOFF)
567 and .debug_info (DWARF2) sections then .mdebug is inserted first
568 (searched last) and DWARF2 is inserted last (searched first). If
569 we don't do this then the XCOFF info is found first - for code in
570 an included file XCOFF info is useless. */
571
572 if (ei.mdebugsect)
573 {
574 const struct ecoff_debug_swap *swap;
575
576 /* .mdebug section, presumably holding ECOFF debugging
577 information. */
578 swap = get_elf_backend_data (abfd)->elf_backend_ecoff_debug_swap;
579 if (swap)
580 elfmdebug_build_psymtabs (objfile, swap, ei.mdebugsect);
581 }
582 if (ei.stabsect)
583 {
584 asection *str_sect;
585
586 /* Stab sections have an associated string table that looks like
587 a separate section. */
588 str_sect = bfd_get_section_by_name (abfd, ".stabstr");
589
590 /* FIXME should probably warn about a stab section without a stabstr. */
591 if (str_sect)
592 elfstab_build_psymtabs (objfile,
593 mainline,
594 ei.stabsect->filepos,
595 bfd_section_size (abfd, ei.stabsect),
596 str_sect->filepos,
597 bfd_section_size (abfd, str_sect));
598 }
599 if (dwarf2_has_info (abfd))
600 {
601 /* DWARF 2 sections */
602 dwarf2_build_psymtabs (objfile, mainline);
603 }
604 else if (ei.dboffset && ei.lnoffset)
605 {
606 /* DWARF sections */
607 dwarf_build_psymtabs (objfile,
608 mainline,
609 ei.dboffset, ei.dbsize,
610 ei.lnoffset, ei.lnsize);
611 }
612
613 if (DWARF2_BUILD_FRAME_INFO_P ())
614 DWARF2_BUILD_FRAME_INFO(objfile);
615
616 /* Install any minimal symbols that have been collected as the current
617 minimal symbols for this objfile. */
618
619 install_minimal_symbols (objfile);
620
621 do_cleanups (back_to);
622 }
623
624 /* This cleans up the objfile's sym_stab_info pointer, and the chain of
625 stab_section_info's, that might be dangling from it. */
626
627 static void
628 free_elfinfo (void *objp)
629 {
630 struct objfile *objfile = (struct objfile *) objp;
631 struct dbx_symfile_info *dbxinfo = objfile->sym_stab_info;
632 struct stab_section_info *ssi, *nssi;
633
634 ssi = dbxinfo->stab_section_info;
635 while (ssi)
636 {
637 nssi = ssi->next;
638 xmfree (objfile->md, ssi);
639 ssi = nssi;
640 }
641
642 dbxinfo->stab_section_info = 0; /* Just say No mo info about this. */
643 }
644
645
646 /* Initialize anything that needs initializing when a completely new symbol
647 file is specified (not just adding some symbols from another file, e.g. a
648 shared library).
649
650 We reinitialize buildsym, since we may be reading stabs from an ELF file. */
651
652 static void
653 elf_new_init (struct objfile *ignore)
654 {
655 stabsread_new_init ();
656 buildsym_new_init ();
657 }
658
659 /* Perform any local cleanups required when we are done with a particular
660 objfile. I.E, we are in the process of discarding all symbol information
661 for an objfile, freeing up all memory held for it, and unlinking the
662 objfile struct from the global list of known objfiles. */
663
664 static void
665 elf_symfile_finish (struct objfile *objfile)
666 {
667 if (objfile->sym_stab_info != NULL)
668 {
669 xmfree (objfile->md, objfile->sym_stab_info);
670 }
671 }
672
673 /* ELF specific initialization routine for reading symbols.
674
675 It is passed a pointer to a struct sym_fns which contains, among other
676 things, the BFD for the file whose symbols are being read, and a slot for
677 a pointer to "private data" which we can fill with goodies.
678
679 For now at least, we have nothing in particular to do, so this function is
680 just a stub. */
681
682 static void
683 elf_symfile_init (struct objfile *objfile)
684 {
685 /* ELF objects may be reordered, so set OBJF_REORDERED. If we
686 find this causes a significant slowdown in gdb then we could
687 set it in the debug symbol readers only when necessary. */
688 objfile->flags |= OBJF_REORDERED;
689 }
690
691 /* When handling an ELF file that contains Sun STABS debug info,
692 some of the debug info is relative to the particular chunk of the
693 section that was generated in its individual .o file. E.g.
694 offsets to static variables are relative to the start of the data
695 segment *for that module before linking*. This information is
696 painfully squirreled away in the ELF symbol table as local symbols
697 with wierd names. Go get 'em when needed. */
698
699 void
700 elfstab_offset_sections (struct objfile *objfile, struct partial_symtab *pst)
701 {
702 char *filename = pst->filename;
703 struct dbx_symfile_info *dbx = objfile->sym_stab_info;
704 struct stab_section_info *maybe = dbx->stab_section_info;
705 struct stab_section_info *questionable = 0;
706 int i;
707 char *p;
708
709 /* The ELF symbol info doesn't include path names, so strip the path
710 (if any) from the psymtab filename. */
711 while (0 != (p = strchr (filename, '/')))
712 filename = p + 1;
713
714 /* FIXME: This linear search could speed up significantly
715 if it was chained in the right order to match how we search it,
716 and if we unchained when we found a match. */
717 for (; maybe; maybe = maybe->next)
718 {
719 if (filename[0] == maybe->filename[0]
720 && STREQ (filename, maybe->filename))
721 {
722 /* We found a match. But there might be several source files
723 (from different directories) with the same name. */
724 if (0 == maybe->found)
725 break;
726 questionable = maybe; /* Might use it later. */
727 }
728 }
729
730 if (maybe == 0 && questionable != 0)
731 {
732 complaint (&symfile_complaints,
733 "elf/stab section information questionable for %s", filename);
734 maybe = questionable;
735 }
736
737 if (maybe)
738 {
739 /* Found it! Allocate a new psymtab struct, and fill it in. */
740 maybe->found++;
741 pst->section_offsets = (struct section_offsets *)
742 obstack_alloc (&objfile->psymbol_obstack, SIZEOF_SECTION_OFFSETS);
743 for (i = 0; i < SECT_OFF_MAX; i++)
744 (pst->section_offsets)->offsets[i] = maybe->sections[i];
745 return;
746 }
747
748 /* We were unable to find any offsets for this file. Complain. */
749 if (dbx->stab_section_info) /* If there *is* any info, */
750 complaint (&symfile_complaints,
751 "elf/stab section information missing for %s", filename);
752 }
753 \f
754 /* Register that we are able to handle ELF object file formats. */
755
756 static struct sym_fns elf_sym_fns =
757 {
758 bfd_target_elf_flavour,
759 elf_new_init, /* sym_new_init: init anything gbl to entire symtab */
760 elf_symfile_init, /* sym_init: read initial info, setup for sym_read() */
761 elf_symfile_read, /* sym_read: read a symbol file into symtab */
762 elf_symfile_finish, /* sym_finish: finished with file, cleanup */
763 default_symfile_offsets, /* sym_offsets: Translate ext. to int. relocation */
764 NULL /* next: pointer to next struct sym_fns */
765 };
766
767 void
768 _initialize_elfread (void)
769 {
770 add_symtab_fns (&elf_sym_fns);
771 }