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c906108c SS |
1 | /* Read ELF (Executable and Linking Format) object files for GDB. |
2 | Copyright 1991, 92, 93, 94, 95, 96, 1998 Free Software Foundation, Inc. | |
3 | Written by Fred Fish at Cygnus Support. | |
4 | ||
c5aa993b | 5 | This file is part of GDB. |
c906108c | 6 | |
c5aa993b JM |
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. | |
c906108c | 11 | |
c5aa993b JM |
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. | |
c906108c | 16 | |
c5aa993b JM |
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, | |
20 | Boston, MA 02111-1307, USA. */ | |
c906108c SS |
21 | |
22 | #include "defs.h" | |
23 | #include "bfd.h" | |
24 | #include "gdb_string.h" | |
25 | #include "elf-bfd.h" | |
26 | #include "elf/mips.h" | |
27 | #include "symtab.h" | |
28 | #include "symfile.h" | |
29 | #include "objfiles.h" | |
30 | #include "buildsym.h" | |
31 | #include "stabsread.h" | |
32 | #include "gdb-stabs.h" | |
33 | #include "complaints.h" | |
34 | #include "demangle.h" | |
35 | ||
392a587b JM |
36 | extern void _initialize_elfread PARAMS ((void)); |
37 | ||
c906108c SS |
38 | /* The struct elfinfo is available only during ELF symbol table and |
39 | psymtab reading. It is destroyed at the complation of psymtab-reading. | |
40 | It's local to elf_symfile_read. */ | |
41 | ||
c5aa993b JM |
42 | struct elfinfo |
43 | { | |
44 | file_ptr dboffset; /* Offset to dwarf debug section */ | |
45 | unsigned int dbsize; /* Size of dwarf debug section */ | |
46 | file_ptr lnoffset; /* Offset to dwarf line number section */ | |
47 | unsigned int lnsize; /* Size of dwarf line number section */ | |
48 | asection *stabsect; /* Section pointer for .stab section */ | |
49 | asection *stabindexsect; /* Section pointer for .stab.index section */ | |
50 | asection *mdebugsect; /* Section pointer for .mdebug section */ | |
51 | }; | |
c906108c SS |
52 | |
53 | /* Various things we might complain about... */ | |
54 | ||
c5aa993b JM |
55 | struct complaint section_info_complaint = |
56 | {"elf/stab section information %s without a preceding file symbol", 0, 0}; | |
c906108c | 57 | |
c5aa993b JM |
58 | struct complaint section_info_dup_complaint = |
59 | {"duplicated elf/stab section information for %s", 0, 0}; | |
c906108c | 60 | |
c5aa993b JM |
61 | struct complaint stab_info_mismatch_complaint = |
62 | {"elf/stab section information missing for %s", 0, 0}; | |
c906108c | 63 | |
c5aa993b JM |
64 | struct complaint stab_info_questionable_complaint = |
65 | {"elf/stab section information questionable for %s", 0, 0}; | |
c906108c SS |
66 | |
67 | static void | |
68 | elf_symfile_init PARAMS ((struct objfile *)); | |
69 | ||
70 | static void | |
71 | elf_new_init PARAMS ((struct objfile *)); | |
72 | ||
73 | static void | |
74 | elf_symfile_read PARAMS ((struct objfile *, struct section_offsets *, int)); | |
75 | ||
76 | static void | |
77 | elf_symfile_finish PARAMS ((struct objfile *)); | |
78 | ||
79 | static void | |
c5aa993b | 80 | elf_symtab_read PARAMS ((bfd *, CORE_ADDR, struct objfile *, int)); |
c906108c SS |
81 | |
82 | static void | |
83 | free_elfinfo PARAMS ((void *)); | |
84 | ||
85 | static struct minimal_symbol * | |
c5aa993b JM |
86 | record_minimal_symbol_and_info PARAMS ((char *, CORE_ADDR, |
87 | enum minimal_symbol_type, char *, | |
88 | asection * bfd_section, | |
89 | struct objfile *)); | |
c906108c SS |
90 | |
91 | static void | |
92 | elf_locate_sections PARAMS ((bfd *, asection *, void *)); | |
93 | ||
94 | /* We are called once per section from elf_symfile_read. We | |
95 | need to examine each section we are passed, check to see | |
96 | if it is something we are interested in processing, and | |
97 | if so, stash away some access information for the section. | |
98 | ||
99 | For now we recognize the dwarf debug information sections and | |
100 | line number sections from matching their section names. The | |
101 | ELF definition is no real help here since it has no direct | |
102 | knowledge of DWARF (by design, so any debugging format can be | |
103 | used). | |
104 | ||
105 | We also recognize the ".stab" sections used by the Sun compilers | |
106 | released with Solaris 2. | |
107 | ||
108 | FIXME: The section names should not be hardwired strings (what | |
109 | should they be? I don't think most object file formats have enough | |
110 | section flags to specify what kind of debug section it is | |
111 | -kingdon). */ | |
112 | ||
113 | static void | |
114 | elf_locate_sections (ignore_abfd, sectp, eip) | |
115 | bfd *ignore_abfd; | |
116 | asection *sectp; | |
117 | PTR eip; | |
118 | { | |
119 | register struct elfinfo *ei; | |
120 | ||
121 | ei = (struct elfinfo *) eip; | |
c5aa993b | 122 | if (STREQ (sectp->name, ".debug")) |
c906108c | 123 | { |
c5aa993b JM |
124 | ei->dboffset = sectp->filepos; |
125 | ei->dbsize = bfd_get_section_size_before_reloc (sectp); | |
c906108c | 126 | } |
c5aa993b | 127 | else if (STREQ (sectp->name, ".line")) |
c906108c | 128 | { |
c5aa993b JM |
129 | ei->lnoffset = sectp->filepos; |
130 | ei->lnsize = bfd_get_section_size_before_reloc (sectp); | |
c906108c | 131 | } |
c5aa993b | 132 | else if (STREQ (sectp->name, ".stab")) |
c906108c | 133 | { |
c5aa993b | 134 | ei->stabsect = sectp; |
c906108c | 135 | } |
c5aa993b | 136 | else if (STREQ (sectp->name, ".stab.index")) |
c906108c | 137 | { |
c5aa993b | 138 | ei->stabindexsect = sectp; |
c906108c | 139 | } |
c5aa993b | 140 | else if (STREQ (sectp->name, ".mdebug")) |
c906108c | 141 | { |
c5aa993b | 142 | ei->mdebugsect = sectp; |
c906108c SS |
143 | } |
144 | } | |
145 | ||
c5aa993b | 146 | #if 0 /* Currently unused */ |
c906108c SS |
147 | |
148 | char * | |
149 | elf_interpreter (abfd) | |
150 | bfd *abfd; | |
151 | { | |
152 | sec_ptr interp_sec; | |
153 | unsigned size; | |
154 | char *interp = NULL; | |
155 | ||
156 | interp_sec = bfd_get_section_by_name (abfd, ".interp"); | |
157 | if (interp_sec) | |
158 | { | |
159 | size = bfd_section_size (abfd, interp_sec); | |
160 | interp = alloca (size); | |
c5aa993b | 161 | if (bfd_get_section_contents (abfd, interp_sec, interp, (file_ptr) 0, |
c906108c SS |
162 | size)) |
163 | { | |
164 | interp = savestring (interp, size - 1); | |
165 | } | |
166 | else | |
167 | { | |
168 | interp = NULL; | |
169 | } | |
170 | } | |
171 | return (interp); | |
172 | } | |
173 | ||
174 | #endif | |
175 | ||
176 | static struct minimal_symbol * | |
177 | record_minimal_symbol_and_info (name, address, ms_type, info, bfd_section, | |
178 | objfile) | |
179 | char *name; | |
180 | CORE_ADDR address; | |
181 | enum minimal_symbol_type ms_type; | |
182 | char *info; /* FIXME, is this really char *? */ | |
183 | asection *bfd_section; | |
184 | struct objfile *objfile; | |
185 | { | |
186 | int section; | |
187 | ||
188 | /* Guess the section from the type. This is likely to be wrong in | |
189 | some cases. */ | |
190 | switch (ms_type) | |
191 | { | |
192 | case mst_text: | |
193 | case mst_file_text: | |
194 | section = SECT_OFF_TEXT; | |
195 | #ifdef SMASH_TEXT_ADDRESS | |
196 | SMASH_TEXT_ADDRESS (address); | |
197 | #endif | |
198 | break; | |
199 | case mst_data: | |
200 | case mst_file_data: | |
201 | section = SECT_OFF_DATA; | |
202 | break; | |
203 | case mst_bss: | |
204 | case mst_file_bss: | |
205 | section = SECT_OFF_BSS; | |
206 | break; | |
207 | default: | |
208 | section = -1; | |
209 | break; | |
210 | } | |
211 | ||
212 | return prim_record_minimal_symbol_and_info | |
213 | (name, address, ms_type, info, section, bfd_section, objfile); | |
214 | } | |
215 | ||
216 | /* | |
217 | ||
c5aa993b | 218 | LOCAL FUNCTION |
c906108c | 219 | |
c5aa993b | 220 | elf_symtab_read -- read the symbol table of an ELF file |
c906108c | 221 | |
c5aa993b | 222 | SYNOPSIS |
c906108c | 223 | |
c5aa993b JM |
224 | void elf_symtab_read (bfd *abfd, CORE_ADDR addr, |
225 | struct objfile *objfile, int dynamic) | |
c906108c | 226 | |
c5aa993b | 227 | DESCRIPTION |
c906108c | 228 | |
c5aa993b JM |
229 | Given an open bfd, a base address to relocate symbols to, and a |
230 | flag that specifies whether or not this bfd is for an executable | |
231 | or not (may be shared library for example), add all the global | |
232 | function and data symbols to the minimal symbol table. | |
c906108c | 233 | |
c5aa993b JM |
234 | In stabs-in-ELF, as implemented by Sun, there are some local symbols |
235 | defined in the ELF symbol table, which can be used to locate | |
236 | the beginnings of sections from each ".o" file that was linked to | |
237 | form the executable objfile. We gather any such info and record it | |
238 | in data structures hung off the objfile's private data. | |
c906108c | 239 | |
c5aa993b | 240 | */ |
c906108c SS |
241 | |
242 | static void | |
243 | elf_symtab_read (abfd, addr, objfile, dynamic) | |
244 | bfd *abfd; | |
245 | CORE_ADDR addr; | |
246 | struct objfile *objfile; | |
247 | int dynamic; | |
248 | { | |
249 | long storage_needed; | |
250 | asymbol *sym; | |
251 | asymbol **symbol_table; | |
252 | long number_of_symbols; | |
253 | long i; | |
254 | int index; | |
255 | struct cleanup *back_to; | |
256 | CORE_ADDR symaddr; | |
257 | enum minimal_symbol_type ms_type; | |
258 | /* If sectinfo is nonNULL, it contains section info that should end up | |
259 | filed in the objfile. */ | |
260 | struct stab_section_info *sectinfo = NULL; | |
261 | /* If filesym is nonzero, it points to a file symbol, but we haven't | |
262 | seen any section info for it yet. */ | |
263 | asymbol *filesym = 0; | |
264 | #ifdef SOFUN_ADDRESS_MAYBE_MISSING | |
265 | /* Name of filesym, as saved on the symbol_obstack. */ | |
266 | char *filesymname = obsavestring ("", 0, &objfile->symbol_obstack); | |
267 | #endif | |
268 | struct dbx_symfile_info *dbx = objfile->sym_stab_info; | |
269 | unsigned long size; | |
270 | int stripped = (bfd_get_symcount (abfd) == 0); | |
c5aa993b | 271 | |
c906108c SS |
272 | if (dynamic) |
273 | { | |
274 | storage_needed = bfd_get_dynamic_symtab_upper_bound (abfd); | |
275 | ||
276 | /* Nothing to be done if there is no dynamic symtab. */ | |
277 | if (storage_needed < 0) | |
278 | return; | |
279 | } | |
280 | else | |
281 | { | |
282 | storage_needed = bfd_get_symtab_upper_bound (abfd); | |
283 | if (storage_needed < 0) | |
284 | error ("Can't read symbols from %s: %s", bfd_get_filename (abfd), | |
285 | bfd_errmsg (bfd_get_error ())); | |
286 | } | |
287 | if (storage_needed > 0) | |
288 | { | |
289 | symbol_table = (asymbol **) xmalloc (storage_needed); | |
290 | back_to = make_cleanup (free, symbol_table); | |
291 | if (dynamic) | |
c5aa993b | 292 | number_of_symbols = bfd_canonicalize_dynamic_symtab (abfd, |
c906108c SS |
293 | symbol_table); |
294 | else | |
c5aa993b | 295 | number_of_symbols = bfd_canonicalize_symtab (abfd, symbol_table); |
c906108c SS |
296 | if (number_of_symbols < 0) |
297 | error ("Can't read symbols from %s: %s", bfd_get_filename (abfd), | |
298 | bfd_errmsg (bfd_get_error ())); | |
299 | for (i = 0; i < number_of_symbols; i++) | |
300 | { | |
301 | sym = symbol_table[i]; | |
c5aa993b | 302 | if (sym->name == NULL || *sym->name == '\0') |
c906108c SS |
303 | { |
304 | /* Skip names that don't exist (shouldn't happen), or names | |
c5aa993b | 305 | that are null strings (may happen). */ |
c906108c SS |
306 | continue; |
307 | } | |
308 | ||
309 | if (dynamic | |
c5aa993b JM |
310 | && sym->section == &bfd_und_section |
311 | && (sym->flags & BSF_FUNCTION)) | |
c906108c SS |
312 | { |
313 | struct minimal_symbol *msym; | |
314 | ||
315 | /* Symbol is a reference to a function defined in | |
c5aa993b JM |
316 | a shared library. |
317 | If its value is non zero then it is usually the address | |
318 | of the corresponding entry in the procedure linkage table, | |
319 | relative to the base address. | |
320 | If its value is zero then the dynamic linker has to resolve | |
321 | the symbol. We are unable to find any meaningful address | |
322 | for this symbol in the executable file, so we skip it. */ | |
323 | symaddr = sym->value; | |
c906108c SS |
324 | if (symaddr == 0) |
325 | continue; | |
326 | symaddr += addr; | |
327 | msym = record_minimal_symbol_and_info | |
c5aa993b JM |
328 | ((char *) sym->name, symaddr, |
329 | mst_solib_trampoline, NULL, sym->section, objfile); | |
c906108c SS |
330 | #ifdef SOFUN_ADDRESS_MAYBE_MISSING |
331 | if (msym != NULL) | |
332 | msym->filename = filesymname; | |
333 | #endif | |
334 | continue; | |
335 | } | |
336 | ||
337 | /* If it is a nonstripped executable, do not enter dynamic | |
338 | symbols, as the dynamic symbol table is usually a subset | |
339 | of the main symbol table. */ | |
340 | if (dynamic && !stripped) | |
341 | continue; | |
c5aa993b | 342 | if (sym->flags & BSF_FILE) |
c906108c SS |
343 | { |
344 | /* STT_FILE debugging symbol that helps stabs-in-elf debugging. | |
c5aa993b | 345 | Chain any old one onto the objfile; remember new sym. */ |
c906108c SS |
346 | if (sectinfo != NULL) |
347 | { | |
c5aa993b JM |
348 | sectinfo->next = dbx->stab_section_info; |
349 | dbx->stab_section_info = sectinfo; | |
c906108c SS |
350 | sectinfo = NULL; |
351 | } | |
352 | filesym = sym; | |
353 | #ifdef SOFUN_ADDRESS_MAYBE_MISSING | |
354 | filesymname = | |
c5aa993b | 355 | obsavestring ((char *) filesym->name, strlen (filesym->name), |
c906108c SS |
356 | &objfile->symbol_obstack); |
357 | #endif | |
358 | } | |
c5aa993b | 359 | else if (sym->flags & (BSF_GLOBAL | BSF_LOCAL | BSF_WEAK)) |
c906108c SS |
360 | { |
361 | struct minimal_symbol *msym; | |
362 | ||
363 | /* Select global/local/weak symbols. Note that bfd puts abs | |
c5aa993b JM |
364 | symbols in their own section, so all symbols we are |
365 | interested in will have a section. */ | |
c906108c | 366 | /* Bfd symbols are section relative. */ |
c5aa993b | 367 | symaddr = sym->value + sym->section->vma; |
c906108c | 368 | /* Relocate all non-absolute symbols by base address. */ |
c5aa993b | 369 | if (sym->section != &bfd_abs_section) |
c906108c SS |
370 | { |
371 | symaddr += addr; | |
372 | } | |
373 | /* For non-absolute symbols, use the type of the section | |
c5aa993b JM |
374 | they are relative to, to intuit text/data. Bfd provides |
375 | no way of figuring this out for absolute symbols. */ | |
376 | if (sym->section == &bfd_abs_section) | |
c906108c SS |
377 | { |
378 | /* This is a hack to get the minimal symbol type | |
379 | right for Irix 5, which has absolute adresses | |
380 | with special section indices for dynamic symbols. */ | |
381 | unsigned short shndx = | |
c5aa993b | 382 | ((elf_symbol_type *) sym)->internal_elf_sym.st_shndx; |
c906108c SS |
383 | |
384 | switch (shndx) | |
385 | { | |
386 | case SHN_MIPS_TEXT: | |
387 | ms_type = mst_text; | |
388 | break; | |
389 | case SHN_MIPS_DATA: | |
390 | ms_type = mst_data; | |
391 | break; | |
392 | case SHN_MIPS_ACOMMON: | |
393 | ms_type = mst_bss; | |
394 | break; | |
395 | default: | |
396 | ms_type = mst_abs; | |
397 | } | |
398 | ||
399 | /* If it is an Irix dynamic symbol, skip section name | |
400 | symbols, relocate all others. */ | |
401 | if (ms_type != mst_abs) | |
402 | { | |
403 | if (sym->name[0] == '.') | |
404 | continue; | |
405 | symaddr += addr; | |
406 | } | |
407 | } | |
c5aa993b | 408 | else if (sym->section->flags & SEC_CODE) |
c906108c | 409 | { |
c5aa993b | 410 | if (sym->flags & BSF_GLOBAL) |
c906108c SS |
411 | { |
412 | ms_type = mst_text; | |
413 | } | |
414 | else if ((sym->name[0] == '.' && sym->name[1] == 'L') | |
c5aa993b | 415 | || ((sym->flags & BSF_LOCAL) |
c906108c SS |
416 | && sym->name[0] == '$' |
417 | && sym->name[1] == 'L')) | |
418 | /* Looks like a compiler-generated label. Skip it. | |
419 | The assembler should be skipping these (to keep | |
420 | executables small), but apparently with gcc on the | |
421 | delta m88k SVR4, it loses. So to have us check too | |
422 | should be harmless (but I encourage people to fix this | |
423 | in the assembler instead of adding checks here). */ | |
424 | continue; | |
425 | #ifdef HARRIS_TARGET | |
426 | else if (sym->name[0] == '.' && sym->name[1] == '.') | |
427 | { | |
428 | /* Looks like a Harris compiler generated label for the | |
c5aa993b JM |
429 | purpose of marking instructions that are relevant to |
430 | DWARF dies. The assembler can't get rid of these | |
431 | because they are relocatable addresses that the | |
432 | linker needs to resolve. */ | |
c906108c SS |
433 | continue; |
434 | } | |
c5aa993b | 435 | #endif |
c906108c SS |
436 | else |
437 | { | |
438 | ms_type = mst_file_text; | |
439 | } | |
440 | } | |
c5aa993b | 441 | else if (sym->section->flags & SEC_ALLOC) |
c906108c | 442 | { |
c5aa993b | 443 | if (sym->flags & BSF_GLOBAL) |
c906108c | 444 | { |
c5aa993b | 445 | if (sym->section->flags & SEC_LOAD) |
c906108c SS |
446 | { |
447 | ms_type = mst_data; | |
448 | } | |
449 | else | |
450 | { | |
451 | ms_type = mst_bss; | |
452 | } | |
453 | } | |
c5aa993b | 454 | else if (sym->flags & BSF_LOCAL) |
c906108c SS |
455 | { |
456 | /* Named Local variable in a Data section. Check its | |
c5aa993b JM |
457 | name for stabs-in-elf. The STREQ macro checks the |
458 | first character inline, so we only actually do a | |
459 | strcmp function call on names that start with 'B' | |
460 | or 'D' */ | |
c906108c | 461 | index = SECT_OFF_MAX; |
c5aa993b | 462 | if (STREQ ("Bbss.bss", sym->name)) |
c906108c SS |
463 | { |
464 | index = SECT_OFF_BSS; | |
465 | } | |
c5aa993b | 466 | else if (STREQ ("Ddata.data", sym->name)) |
c906108c SS |
467 | { |
468 | index = SECT_OFF_DATA; | |
469 | } | |
c5aa993b | 470 | else if (STREQ ("Drodata.rodata", sym->name)) |
c906108c SS |
471 | { |
472 | index = SECT_OFF_RODATA; | |
473 | } | |
474 | if (index != SECT_OFF_MAX) | |
475 | { | |
476 | /* Found a special local symbol. Allocate a | |
477 | sectinfo, if needed, and fill it in. */ | |
478 | if (sectinfo == NULL) | |
479 | { | |
480 | sectinfo = (struct stab_section_info *) | |
c5aa993b | 481 | xmmalloc (objfile->md, sizeof (*sectinfo)); |
c906108c SS |
482 | memset ((PTR) sectinfo, 0, sizeof (*sectinfo)); |
483 | if (filesym == NULL) | |
484 | { | |
485 | complain (§ion_info_complaint, | |
c5aa993b | 486 | sym->name); |
c906108c SS |
487 | } |
488 | else | |
489 | { | |
c5aa993b JM |
490 | sectinfo->filename = |
491 | (char *) filesym->name; | |
c906108c SS |
492 | } |
493 | } | |
c5aa993b | 494 | if (sectinfo->sections[index] != 0) |
c906108c SS |
495 | { |
496 | complain (§ion_info_dup_complaint, | |
c5aa993b | 497 | sectinfo->filename); |
c906108c SS |
498 | } |
499 | /* Bfd symbols are section relative. */ | |
c5aa993b | 500 | symaddr = sym->value + sym->section->vma; |
c906108c | 501 | /* Relocate non-absolute symbols by base address. */ |
c5aa993b | 502 | if (sym->section != &bfd_abs_section) |
c906108c SS |
503 | { |
504 | symaddr += addr; | |
505 | } | |
c5aa993b | 506 | sectinfo->sections[index] = symaddr; |
c906108c SS |
507 | /* The special local symbols don't go in the |
508 | minimal symbol table, so ignore this one. */ | |
509 | continue; | |
510 | } | |
511 | /* Not a special stabs-in-elf symbol, do regular | |
c5aa993b JM |
512 | symbol processing. */ |
513 | if (sym->section->flags & SEC_LOAD) | |
c906108c SS |
514 | { |
515 | ms_type = mst_file_data; | |
516 | } | |
517 | else | |
518 | { | |
519 | ms_type = mst_file_bss; | |
520 | } | |
521 | } | |
522 | else | |
523 | { | |
524 | ms_type = mst_unknown; | |
525 | } | |
526 | } | |
527 | else | |
528 | { | |
529 | /* FIXME: Solaris2 shared libraries include lots of | |
530 | odd "absolute" and "undefined" symbols, that play | |
531 | hob with actions like finding what function the PC | |
532 | is in. Ignore them if they aren't text, data, or bss. */ | |
533 | /* ms_type = mst_unknown; */ | |
c5aa993b | 534 | continue; /* Skip this symbol. */ |
c906108c SS |
535 | } |
536 | /* Pass symbol size field in via BFD. FIXME!!! */ | |
c5aa993b | 537 | size = ((elf_symbol_type *) sym)->internal_elf_sym.st_size; |
c906108c | 538 | msym = record_minimal_symbol_and_info |
c5aa993b JM |
539 | ((char *) sym->name, symaddr, |
540 | ms_type, (PTR) size, sym->section, objfile); | |
c906108c SS |
541 | #ifdef SOFUN_ADDRESS_MAYBE_MISSING |
542 | if (msym != NULL) | |
543 | msym->filename = filesymname; | |
544 | #endif | |
545 | #ifdef ELF_MAKE_MSYMBOL_SPECIAL | |
c5aa993b | 546 | ELF_MAKE_MSYMBOL_SPECIAL (sym, msym); |
c906108c SS |
547 | #endif |
548 | } | |
549 | } | |
550 | do_cleanups (back_to); | |
551 | } | |
552 | } | |
553 | ||
554 | /* Scan and build partial symbols for a symbol file. | |
555 | We have been initialized by a call to elf_symfile_init, which | |
556 | currently does nothing. | |
557 | ||
558 | SECTION_OFFSETS is a set of offsets to apply to relocate the symbols | |
559 | in each section. We simplify it down to a single offset for all | |
560 | symbols. FIXME. | |
561 | ||
562 | MAINLINE is true if we are reading the main symbol | |
563 | table (as opposed to a shared lib or dynamically loaded file). | |
564 | ||
565 | This function only does the minimum work necessary for letting the | |
566 | user "name" things symbolically; it does not read the entire symtab. | |
567 | Instead, it reads the external and static symbols and puts them in partial | |
568 | symbol tables. When more extensive information is requested of a | |
569 | file, the corresponding partial symbol table is mutated into a full | |
570 | fledged symbol table by going back and reading the symbols | |
571 | for real. | |
572 | ||
573 | We look for sections with specific names, to tell us what debug | |
574 | format to look for: FIXME!!! | |
575 | ||
576 | dwarf_build_psymtabs() builds psymtabs for DWARF symbols; | |
577 | elfstab_build_psymtabs() handles STABS symbols; | |
578 | mdebug_build_psymtabs() handles ECOFF debugging information. | |
579 | ||
580 | Note that ELF files have a "minimal" symbol table, which looks a lot | |
581 | like a COFF symbol table, but has only the minimal information necessary | |
582 | for linking. We process this also, and use the information to | |
583 | build gdb's minimal symbol table. This gives us some minimal debugging | |
584 | capability even for files compiled without -g. */ | |
585 | ||
586 | static void | |
587 | elf_symfile_read (objfile, section_offsets, mainline) | |
588 | struct objfile *objfile; | |
589 | struct section_offsets *section_offsets; | |
590 | int mainline; | |
591 | { | |
592 | bfd *abfd = objfile->obfd; | |
593 | struct elfinfo ei; | |
594 | struct cleanup *back_to; | |
595 | CORE_ADDR offset; | |
596 | ||
597 | init_minimal_symbol_collection (); | |
598 | back_to = make_cleanup ((make_cleanup_func) discard_minimal_symbols, 0); | |
599 | ||
600 | memset ((char *) &ei, 0, sizeof (ei)); | |
601 | ||
602 | /* Allocate struct to keep track of the symfile */ | |
603 | objfile->sym_stab_info = (struct dbx_symfile_info *) | |
c5aa993b | 604 | xmmalloc (objfile->md, sizeof (struct dbx_symfile_info)); |
c906108c SS |
605 | memset ((char *) objfile->sym_stab_info, 0, sizeof (struct dbx_symfile_info)); |
606 | make_cleanup (free_elfinfo, (PTR) objfile); | |
607 | ||
608 | /* Process the normal ELF symbol table first. This may write some | |
609 | chain of info into the dbx_symfile_info in objfile->sym_stab_info, | |
610 | which can later be used by elfstab_offset_sections. */ | |
611 | ||
612 | /* FIXME, should take a section_offsets param, not just an offset. */ | |
613 | offset = ANOFFSET (section_offsets, 0); | |
614 | elf_symtab_read (abfd, offset, objfile, 0); | |
615 | ||
616 | /* Add the dynamic symbols. */ | |
617 | ||
618 | elf_symtab_read (abfd, offset, objfile, 1); | |
619 | ||
620 | /* Now process debugging information, which is contained in | |
621 | special ELF sections. */ | |
622 | ||
623 | /* If we are reinitializing, or if we have never loaded syms yet, | |
624 | set table to empty. MAINLINE is cleared so that *_read_psymtab | |
625 | functions do not all also re-initialize the psymbol table. */ | |
626 | if (mainline) | |
627 | { | |
628 | init_psymbol_list (objfile, 0); | |
629 | mainline = 0; | |
630 | } | |
631 | ||
632 | /* We first have to find them... */ | |
c5aa993b | 633 | bfd_map_over_sections (abfd, elf_locate_sections, (PTR) & ei); |
c906108c SS |
634 | |
635 | /* ELF debugging information is inserted into the psymtab in the | |
636 | order of least informative first - most informative last. Since | |
637 | the psymtab table is searched `most recent insertion first' this | |
638 | increases the probability that more detailed debug information | |
639 | for a section is found. | |
640 | ||
641 | For instance, an object file might contain both .mdebug (XCOFF) | |
642 | and .debug_info (DWARF2) sections then .mdebug is inserted first | |
643 | (searched last) and DWARF2 is inserted last (searched first). If | |
644 | we don't do this then the XCOFF info is found first - for code in | |
645 | an included file XCOFF info is useless. */ | |
646 | ||
647 | if (ei.mdebugsect) | |
648 | { | |
649 | const struct ecoff_debug_swap *swap; | |
650 | ||
651 | /* .mdebug section, presumably holding ECOFF debugging | |
c5aa993b | 652 | information. */ |
c906108c SS |
653 | swap = get_elf_backend_data (abfd)->elf_backend_ecoff_debug_swap; |
654 | if (swap) | |
655 | elfmdebug_build_psymtabs (objfile, swap, ei.mdebugsect, | |
656 | section_offsets); | |
657 | } | |
658 | if (ei.stabsect) | |
659 | { | |
660 | asection *str_sect; | |
661 | ||
662 | /* Stab sections have an associated string table that looks like | |
c5aa993b | 663 | a separate section. */ |
c906108c SS |
664 | str_sect = bfd_get_section_by_name (abfd, ".stabstr"); |
665 | ||
666 | /* FIXME should probably warn about a stab section without a stabstr. */ | |
667 | if (str_sect) | |
668 | elfstab_build_psymtabs (objfile, | |
669 | section_offsets, | |
670 | mainline, | |
671 | ei.stabsect->filepos, | |
672 | bfd_section_size (abfd, ei.stabsect), | |
673 | str_sect->filepos, | |
674 | bfd_section_size (abfd, str_sect)); | |
675 | } | |
676 | if (dwarf2_has_info (abfd)) | |
677 | { | |
678 | /* DWARF 2 sections */ | |
679 | dwarf2_build_psymtabs (objfile, section_offsets, mainline); | |
680 | } | |
681 | else if (ei.dboffset && ei.lnoffset) | |
682 | { | |
683 | /* DWARF sections */ | |
684 | dwarf_build_psymtabs (objfile, | |
685 | section_offsets, mainline, | |
686 | ei.dboffset, ei.dbsize, | |
687 | ei.lnoffset, ei.lnsize); | |
688 | } | |
689 | ||
690 | /* Install any minimal symbols that have been collected as the current | |
691 | minimal symbols for this objfile. */ | |
692 | ||
693 | install_minimal_symbols (objfile); | |
694 | ||
695 | do_cleanups (back_to); | |
696 | } | |
697 | ||
698 | /* This cleans up the objfile's sym_stab_info pointer, and the chain of | |
699 | stab_section_info's, that might be dangling from it. */ | |
700 | ||
701 | static void | |
702 | free_elfinfo (objp) | |
703 | PTR objp; | |
704 | { | |
c5aa993b | 705 | struct objfile *objfile = (struct objfile *) objp; |
c906108c SS |
706 | struct dbx_symfile_info *dbxinfo = objfile->sym_stab_info; |
707 | struct stab_section_info *ssi, *nssi; | |
708 | ||
709 | ssi = dbxinfo->stab_section_info; | |
710 | while (ssi) | |
711 | { | |
712 | nssi = ssi->next; | |
713 | mfree (objfile->md, ssi); | |
714 | ssi = nssi; | |
715 | } | |
716 | ||
717 | dbxinfo->stab_section_info = 0; /* Just say No mo info about this. */ | |
718 | } | |
719 | ||
720 | ||
721 | /* Initialize anything that needs initializing when a completely new symbol | |
722 | file is specified (not just adding some symbols from another file, e.g. a | |
723 | shared library). | |
724 | ||
725 | We reinitialize buildsym, since we may be reading stabs from an ELF file. */ | |
726 | ||
727 | static void | |
728 | elf_new_init (ignore) | |
729 | struct objfile *ignore; | |
730 | { | |
731 | stabsread_new_init (); | |
732 | buildsym_new_init (); | |
733 | } | |
734 | ||
735 | /* Perform any local cleanups required when we are done with a particular | |
736 | objfile. I.E, we are in the process of discarding all symbol information | |
737 | for an objfile, freeing up all memory held for it, and unlinking the | |
738 | objfile struct from the global list of known objfiles. */ | |
739 | ||
740 | static void | |
741 | elf_symfile_finish (objfile) | |
742 | struct objfile *objfile; | |
743 | { | |
c5aa993b | 744 | if (objfile->sym_stab_info != NULL) |
c906108c | 745 | { |
c5aa993b | 746 | mfree (objfile->md, objfile->sym_stab_info); |
c906108c SS |
747 | } |
748 | } | |
749 | ||
750 | /* ELF specific initialization routine for reading symbols. | |
751 | ||
752 | It is passed a pointer to a struct sym_fns which contains, among other | |
753 | things, the BFD for the file whose symbols are being read, and a slot for | |
754 | a pointer to "private data" which we can fill with goodies. | |
755 | ||
756 | For now at least, we have nothing in particular to do, so this function is | |
757 | just a stub. */ | |
758 | ||
759 | static void | |
760 | elf_symfile_init (objfile) | |
761 | struct objfile *objfile; | |
762 | { | |
763 | /* ELF objects may be reordered, so set OBJF_REORDERED. If we | |
764 | find this causes a significant slowdown in gdb then we could | |
765 | set it in the debug symbol readers only when necessary. */ | |
766 | objfile->flags |= OBJF_REORDERED; | |
767 | } | |
768 | ||
769 | /* When handling an ELF file that contains Sun STABS debug info, | |
770 | some of the debug info is relative to the particular chunk of the | |
771 | section that was generated in its individual .o file. E.g. | |
772 | offsets to static variables are relative to the start of the data | |
773 | segment *for that module before linking*. This information is | |
774 | painfully squirreled away in the ELF symbol table as local symbols | |
775 | with wierd names. Go get 'em when needed. */ | |
776 | ||
777 | void | |
778 | elfstab_offset_sections (objfile, pst) | |
779 | struct objfile *objfile; | |
780 | struct partial_symtab *pst; | |
781 | { | |
782 | char *filename = pst->filename; | |
783 | struct dbx_symfile_info *dbx = objfile->sym_stab_info; | |
784 | struct stab_section_info *maybe = dbx->stab_section_info; | |
785 | struct stab_section_info *questionable = 0; | |
786 | int i; | |
787 | char *p; | |
788 | ||
789 | /* The ELF symbol info doesn't include path names, so strip the path | |
790 | (if any) from the psymtab filename. */ | |
791 | while (0 != (p = strchr (filename, '/'))) | |
c5aa993b | 792 | filename = p + 1; |
c906108c SS |
793 | |
794 | /* FIXME: This linear search could speed up significantly | |
795 | if it was chained in the right order to match how we search it, | |
796 | and if we unchained when we found a match. */ | |
797 | for (; maybe; maybe = maybe->next) | |
798 | { | |
799 | if (filename[0] == maybe->filename[0] | |
800 | && STREQ (filename, maybe->filename)) | |
801 | { | |
802 | /* We found a match. But there might be several source files | |
803 | (from different directories) with the same name. */ | |
804 | if (0 == maybe->found) | |
805 | break; | |
c5aa993b | 806 | questionable = maybe; /* Might use it later. */ |
c906108c SS |
807 | } |
808 | } | |
809 | ||
810 | if (maybe == 0 && questionable != 0) | |
811 | { | |
812 | complain (&stab_info_questionable_complaint, filename); | |
813 | maybe = questionable; | |
814 | } | |
815 | ||
816 | if (maybe) | |
817 | { | |
818 | /* Found it! Allocate a new psymtab struct, and fill it in. */ | |
819 | maybe->found++; | |
820 | pst->section_offsets = (struct section_offsets *) | |
c5aa993b | 821 | obstack_alloc (&objfile->psymbol_obstack, |
c906108c | 822 | sizeof (struct section_offsets) + |
c5aa993b | 823 | sizeof (pst->section_offsets->offsets) * (SECT_OFF_MAX - 1)); |
c906108c SS |
824 | |
825 | for (i = 0; i < SECT_OFF_MAX; i++) | |
826 | ANOFFSET (pst->section_offsets, i) = maybe->sections[i]; | |
827 | return; | |
828 | } | |
829 | ||
830 | /* We were unable to find any offsets for this file. Complain. */ | |
c5aa993b | 831 | if (dbx->stab_section_info) /* If there *is* any info, */ |
c906108c SS |
832 | complain (&stab_info_mismatch_complaint, filename); |
833 | } | |
834 | \f | |
835 | /* Register that we are able to handle ELF object file formats. */ | |
836 | ||
837 | static struct sym_fns elf_sym_fns = | |
838 | { | |
839 | bfd_target_elf_flavour, | |
c5aa993b JM |
840 | elf_new_init, /* sym_new_init: init anything gbl to entire symtab */ |
841 | elf_symfile_init, /* sym_init: read initial info, setup for sym_read() */ | |
842 | elf_symfile_read, /* sym_read: read a symbol file into symtab */ | |
843 | elf_symfile_finish, /* sym_finish: finished with file, cleanup */ | |
c906108c SS |
844 | default_symfile_offsets, |
845 | /* sym_offsets: Translate ext. to int. relocation */ | |
c5aa993b | 846 | NULL /* next: pointer to next struct sym_fns */ |
c906108c SS |
847 | }; |
848 | ||
849 | void | |
850 | _initialize_elfread () | |
851 | { | |
852 | add_symtab_fns (&elf_sym_fns); | |
853 | } |