Commit | Line | Data |
---|---|---|
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 | 38 | /* The struct elfinfo is available only during ELF symbol table and |
6426a772 | 39 | psymtab reading. It is destroyed at the completion of psymtab-reading. |
c906108c SS |
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 | |
96baa820 | 74 | elf_symfile_read PARAMS ((struct objfile *, int)); |
c906108c SS |
75 | |
76 | static void | |
77 | elf_symfile_finish PARAMS ((struct objfile *)); | |
78 | ||
79 | static void | |
d4f3574e | 80 | elf_symtab_read PARAMS ((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: | |
b8fbeb18 | 194 | section = SECT_OFF_TEXT (objfile); |
c906108c SS |
195 | #ifdef SMASH_TEXT_ADDRESS |
196 | SMASH_TEXT_ADDRESS (address); | |
197 | #endif | |
198 | break; | |
199 | case mst_data: | |
200 | case mst_file_data: | |
b8fbeb18 | 201 | section = SECT_OFF_DATA (objfile); |
c906108c SS |
202 | break; |
203 | case mst_bss: | |
204 | case mst_file_bss: | |
b8fbeb18 | 205 | section = SECT_OFF_BSS (objfile); |
c906108c SS |
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 | |
d4f3574e | 224 | void elf_symtab_read (struct objfile *objfile, int dynamic) |
c906108c | 225 | |
c5aa993b | 226 | DESCRIPTION |
c906108c | 227 | |
d4f3574e SS |
228 | Given an objfile and a flag that specifies whether or not the objfile |
229 | is for an executable or not (may be shared library for example), add | |
230 | all the global function and data symbols to the minimal symbol table. | |
c906108c | 231 | |
c5aa993b JM |
232 | In stabs-in-ELF, as implemented by Sun, there are some local symbols |
233 | defined in the ELF symbol table, which can be used to locate | |
234 | the beginnings of sections from each ".o" file that was linked to | |
235 | form the executable objfile. We gather any such info and record it | |
236 | in data structures hung off the objfile's private data. | |
c906108c | 237 | |
c5aa993b | 238 | */ |
c906108c SS |
239 | |
240 | static void | |
d4f3574e | 241 | elf_symtab_read (objfile, dynamic) |
c906108c SS |
242 | struct objfile *objfile; |
243 | int dynamic; | |
244 | { | |
245 | long storage_needed; | |
246 | asymbol *sym; | |
247 | asymbol **symbol_table; | |
248 | long number_of_symbols; | |
249 | long i; | |
250 | int index; | |
251 | struct cleanup *back_to; | |
252 | CORE_ADDR symaddr; | |
d4f3574e | 253 | CORE_ADDR offset; |
c906108c SS |
254 | enum minimal_symbol_type ms_type; |
255 | /* If sectinfo is nonNULL, it contains section info that should end up | |
256 | filed in the objfile. */ | |
257 | struct stab_section_info *sectinfo = NULL; | |
258 | /* If filesym is nonzero, it points to a file symbol, but we haven't | |
259 | seen any section info for it yet. */ | |
260 | asymbol *filesym = 0; | |
261 | #ifdef SOFUN_ADDRESS_MAYBE_MISSING | |
262 | /* Name of filesym, as saved on the symbol_obstack. */ | |
263 | char *filesymname = obsavestring ("", 0, &objfile->symbol_obstack); | |
264 | #endif | |
265 | struct dbx_symfile_info *dbx = objfile->sym_stab_info; | |
266 | unsigned long size; | |
d4f3574e | 267 | int stripped = (bfd_get_symcount (objfile->obfd) == 0); |
c5aa993b | 268 | |
c906108c SS |
269 | if (dynamic) |
270 | { | |
d4f3574e | 271 | storage_needed = bfd_get_dynamic_symtab_upper_bound (objfile->obfd); |
c906108c SS |
272 | |
273 | /* Nothing to be done if there is no dynamic symtab. */ | |
274 | if (storage_needed < 0) | |
275 | return; | |
276 | } | |
277 | else | |
278 | { | |
d4f3574e | 279 | storage_needed = bfd_get_symtab_upper_bound (objfile->obfd); |
c906108c | 280 | if (storage_needed < 0) |
d4f3574e | 281 | error ("Can't read symbols from %s: %s", bfd_get_filename (objfile->obfd), |
c906108c SS |
282 | bfd_errmsg (bfd_get_error ())); |
283 | } | |
284 | if (storage_needed > 0) | |
285 | { | |
286 | symbol_table = (asymbol **) xmalloc (storage_needed); | |
287 | back_to = make_cleanup (free, symbol_table); | |
288 | if (dynamic) | |
d4f3574e | 289 | number_of_symbols = bfd_canonicalize_dynamic_symtab (objfile->obfd, |
c906108c SS |
290 | symbol_table); |
291 | else | |
d4f3574e | 292 | number_of_symbols = bfd_canonicalize_symtab (objfile->obfd, symbol_table); |
c906108c | 293 | if (number_of_symbols < 0) |
d4f3574e | 294 | error ("Can't read symbols from %s: %s", bfd_get_filename (objfile->obfd), |
c906108c | 295 | bfd_errmsg (bfd_get_error ())); |
70d5406d | 296 | /* FIXME: Should use section specific offset, not SECT_OFF_TEXT. */ |
b8fbeb18 | 297 | offset = ANOFFSET (objfile->section_offsets, SECT_OFF_TEXT (objfile)); |
c906108c SS |
298 | for (i = 0; i < number_of_symbols; i++) |
299 | { | |
300 | sym = symbol_table[i]; | |
c5aa993b | 301 | if (sym->name == NULL || *sym->name == '\0') |
c906108c SS |
302 | { |
303 | /* Skip names that don't exist (shouldn't happen), or names | |
c5aa993b | 304 | that are null strings (may happen). */ |
c906108c SS |
305 | continue; |
306 | } | |
307 | ||
308 | if (dynamic | |
c5aa993b JM |
309 | && sym->section == &bfd_und_section |
310 | && (sym->flags & BSF_FUNCTION)) | |
c906108c SS |
311 | { |
312 | struct minimal_symbol *msym; | |
313 | ||
314 | /* Symbol is a reference to a function defined in | |
c5aa993b JM |
315 | a shared library. |
316 | If its value is non zero then it is usually the address | |
317 | of the corresponding entry in the procedure linkage table, | |
d4f3574e | 318 | plus the desired section offset. |
c5aa993b JM |
319 | If its value is zero then the dynamic linker has to resolve |
320 | the symbol. We are unable to find any meaningful address | |
321 | for this symbol in the executable file, so we skip it. */ | |
322 | symaddr = sym->value; | |
c906108c SS |
323 | if (symaddr == 0) |
324 | continue; | |
d4f3574e | 325 | symaddr += offset; |
c906108c | 326 | msym = record_minimal_symbol_and_info |
c5aa993b JM |
327 | ((char *) sym->name, symaddr, |
328 | mst_solib_trampoline, NULL, sym->section, objfile); | |
c906108c SS |
329 | #ifdef SOFUN_ADDRESS_MAYBE_MISSING |
330 | if (msym != NULL) | |
331 | msym->filename = filesymname; | |
332 | #endif | |
333 | continue; | |
334 | } | |
335 | ||
336 | /* If it is a nonstripped executable, do not enter dynamic | |
337 | symbols, as the dynamic symbol table is usually a subset | |
338 | of the main symbol table. */ | |
339 | if (dynamic && !stripped) | |
340 | continue; | |
c5aa993b | 341 | if (sym->flags & BSF_FILE) |
c906108c SS |
342 | { |
343 | /* STT_FILE debugging symbol that helps stabs-in-elf debugging. | |
c5aa993b | 344 | Chain any old one onto the objfile; remember new sym. */ |
c906108c SS |
345 | if (sectinfo != NULL) |
346 | { | |
c5aa993b JM |
347 | sectinfo->next = dbx->stab_section_info; |
348 | dbx->stab_section_info = sectinfo; | |
c906108c SS |
349 | sectinfo = NULL; |
350 | } | |
351 | filesym = sym; | |
352 | #ifdef SOFUN_ADDRESS_MAYBE_MISSING | |
353 | filesymname = | |
c5aa993b | 354 | obsavestring ((char *) filesym->name, strlen (filesym->name), |
c906108c SS |
355 | &objfile->symbol_obstack); |
356 | #endif | |
357 | } | |
c5aa993b | 358 | else if (sym->flags & (BSF_GLOBAL | BSF_LOCAL | BSF_WEAK)) |
c906108c SS |
359 | { |
360 | struct minimal_symbol *msym; | |
361 | ||
362 | /* Select global/local/weak symbols. Note that bfd puts abs | |
c5aa993b JM |
363 | symbols in their own section, so all symbols we are |
364 | interested in will have a section. */ | |
c906108c | 365 | /* Bfd symbols are section relative. */ |
c5aa993b | 366 | symaddr = sym->value + sym->section->vma; |
d4f3574e | 367 | /* Relocate all non-absolute symbols by the section offset. */ |
c5aa993b | 368 | if (sym->section != &bfd_abs_section) |
c906108c | 369 | { |
d4f3574e | 370 | symaddr += offset; |
c906108c SS |
371 | } |
372 | /* For non-absolute symbols, use the type of the section | |
c5aa993b JM |
373 | they are relative to, to intuit text/data. Bfd provides |
374 | no way of figuring this out for absolute symbols. */ | |
375 | if (sym->section == &bfd_abs_section) | |
c906108c SS |
376 | { |
377 | /* This is a hack to get the minimal symbol type | |
11cf8741 | 378 | right for Irix 5, which has absolute addresses |
c906108c SS |
379 | with special section indices for dynamic symbols. */ |
380 | unsigned short shndx = | |
c5aa993b | 381 | ((elf_symbol_type *) sym)->internal_elf_sym.st_shndx; |
c906108c SS |
382 | |
383 | switch (shndx) | |
384 | { | |
385 | case SHN_MIPS_TEXT: | |
386 | ms_type = mst_text; | |
387 | break; | |
388 | case SHN_MIPS_DATA: | |
389 | ms_type = mst_data; | |
390 | break; | |
391 | case SHN_MIPS_ACOMMON: | |
392 | ms_type = mst_bss; | |
393 | break; | |
394 | default: | |
395 | ms_type = mst_abs; | |
396 | } | |
397 | ||
398 | /* If it is an Irix dynamic symbol, skip section name | |
d4f3574e | 399 | symbols, relocate all others by section offset. */ |
c906108c SS |
400 | if (ms_type != mst_abs) |
401 | { | |
402 | if (sym->name[0] == '.') | |
403 | continue; | |
d4f3574e | 404 | symaddr += offset; |
c906108c SS |
405 | } |
406 | } | |
c5aa993b | 407 | else if (sym->section->flags & SEC_CODE) |
c906108c | 408 | { |
c5aa993b | 409 | if (sym->flags & BSF_GLOBAL) |
c906108c SS |
410 | { |
411 | ms_type = mst_text; | |
412 | } | |
413 | else if ((sym->name[0] == '.' && sym->name[1] == 'L') | |
c5aa993b | 414 | || ((sym->flags & BSF_LOCAL) |
c906108c SS |
415 | && sym->name[0] == '$' |
416 | && sym->name[1] == 'L')) | |
417 | /* Looks like a compiler-generated label. Skip it. | |
418 | The assembler should be skipping these (to keep | |
419 | executables small), but apparently with gcc on the | |
420 | delta m88k SVR4, it loses. So to have us check too | |
421 | should be harmless (but I encourage people to fix this | |
422 | in the assembler instead of adding checks here). */ | |
423 | continue; | |
424 | #ifdef HARRIS_TARGET | |
425 | else if (sym->name[0] == '.' && sym->name[1] == '.') | |
426 | { | |
427 | /* Looks like a Harris compiler generated label for the | |
c5aa993b JM |
428 | purpose of marking instructions that are relevant to |
429 | DWARF dies. The assembler can't get rid of these | |
430 | because they are relocatable addresses that the | |
431 | linker needs to resolve. */ | |
c906108c SS |
432 | continue; |
433 | } | |
c5aa993b | 434 | #endif |
c906108c SS |
435 | else |
436 | { | |
437 | ms_type = mst_file_text; | |
438 | } | |
439 | } | |
c5aa993b | 440 | else if (sym->section->flags & SEC_ALLOC) |
c906108c | 441 | { |
c5aa993b | 442 | if (sym->flags & BSF_GLOBAL) |
c906108c | 443 | { |
c5aa993b | 444 | if (sym->section->flags & SEC_LOAD) |
c906108c SS |
445 | { |
446 | ms_type = mst_data; | |
447 | } | |
448 | else | |
449 | { | |
450 | ms_type = mst_bss; | |
451 | } | |
452 | } | |
c5aa993b | 453 | else if (sym->flags & BSF_LOCAL) |
c906108c SS |
454 | { |
455 | /* Named Local variable in a Data section. Check its | |
c5aa993b JM |
456 | name for stabs-in-elf. The STREQ macro checks the |
457 | first character inline, so we only actually do a | |
458 | strcmp function call on names that start with 'B' | |
459 | or 'D' */ | |
c906108c | 460 | index = SECT_OFF_MAX; |
c5aa993b | 461 | if (STREQ ("Bbss.bss", sym->name)) |
c906108c | 462 | { |
b8fbeb18 | 463 | index = SECT_OFF_BSS (objfile); |
c906108c | 464 | } |
c5aa993b | 465 | else if (STREQ ("Ddata.data", sym->name)) |
c906108c | 466 | { |
b8fbeb18 | 467 | index = SECT_OFF_DATA (objfile); |
c906108c | 468 | } |
c5aa993b | 469 | else if (STREQ ("Drodata.rodata", sym->name)) |
c906108c | 470 | { |
b8fbeb18 | 471 | index = SECT_OFF_RODATA (objfile); |
c906108c SS |
472 | } |
473 | if (index != SECT_OFF_MAX) | |
474 | { | |
475 | /* Found a special local symbol. Allocate a | |
476 | sectinfo, if needed, and fill it in. */ | |
477 | if (sectinfo == NULL) | |
478 | { | |
479 | sectinfo = (struct stab_section_info *) | |
c5aa993b | 480 | xmmalloc (objfile->md, sizeof (*sectinfo)); |
c906108c SS |
481 | memset ((PTR) sectinfo, 0, sizeof (*sectinfo)); |
482 | if (filesym == NULL) | |
483 | { | |
484 | complain (§ion_info_complaint, | |
c5aa993b | 485 | sym->name); |
c906108c SS |
486 | } |
487 | else | |
488 | { | |
c5aa993b JM |
489 | sectinfo->filename = |
490 | (char *) filesym->name; | |
c906108c SS |
491 | } |
492 | } | |
c5aa993b | 493 | if (sectinfo->sections[index] != 0) |
c906108c SS |
494 | { |
495 | complain (§ion_info_dup_complaint, | |
c5aa993b | 496 | sectinfo->filename); |
c906108c SS |
497 | } |
498 | /* Bfd symbols are section relative. */ | |
c5aa993b | 499 | symaddr = sym->value + sym->section->vma; |
d4f3574e | 500 | /* Relocate non-absolute symbols by the section offset. */ |
c5aa993b | 501 | if (sym->section != &bfd_abs_section) |
c906108c | 502 | { |
d4f3574e | 503 | symaddr += offset; |
c906108c | 504 | } |
c5aa993b | 505 | sectinfo->sections[index] = symaddr; |
c906108c SS |
506 | /* The special local symbols don't go in the |
507 | minimal symbol table, so ignore this one. */ | |
508 | continue; | |
509 | } | |
510 | /* Not a special stabs-in-elf symbol, do regular | |
c5aa993b JM |
511 | symbol processing. */ |
512 | if (sym->section->flags & SEC_LOAD) | |
c906108c SS |
513 | { |
514 | ms_type = mst_file_data; | |
515 | } | |
516 | else | |
517 | { | |
518 | ms_type = mst_file_bss; | |
519 | } | |
520 | } | |
521 | else | |
522 | { | |
523 | ms_type = mst_unknown; | |
524 | } | |
525 | } | |
526 | else | |
527 | { | |
528 | /* FIXME: Solaris2 shared libraries include lots of | |
529 | odd "absolute" and "undefined" symbols, that play | |
530 | hob with actions like finding what function the PC | |
531 | is in. Ignore them if they aren't text, data, or bss. */ | |
532 | /* ms_type = mst_unknown; */ | |
c5aa993b | 533 | continue; /* Skip this symbol. */ |
c906108c SS |
534 | } |
535 | /* Pass symbol size field in via BFD. FIXME!!! */ | |
c5aa993b | 536 | size = ((elf_symbol_type *) sym)->internal_elf_sym.st_size; |
c906108c | 537 | msym = record_minimal_symbol_and_info |
c5aa993b JM |
538 | ((char *) sym->name, symaddr, |
539 | ms_type, (PTR) size, sym->section, objfile); | |
c906108c SS |
540 | #ifdef SOFUN_ADDRESS_MAYBE_MISSING |
541 | if (msym != NULL) | |
542 | msym->filename = filesymname; | |
543 | #endif | |
544 | #ifdef ELF_MAKE_MSYMBOL_SPECIAL | |
c5aa993b | 545 | ELF_MAKE_MSYMBOL_SPECIAL (sym, msym); |
c906108c SS |
546 | #endif |
547 | } | |
548 | } | |
549 | do_cleanups (back_to); | |
550 | } | |
551 | } | |
552 | ||
553 | /* Scan and build partial symbols for a symbol file. | |
554 | We have been initialized by a call to elf_symfile_init, which | |
555 | currently does nothing. | |
556 | ||
557 | SECTION_OFFSETS is a set of offsets to apply to relocate the symbols | |
558 | in each section. We simplify it down to a single offset for all | |
559 | symbols. FIXME. | |
560 | ||
561 | MAINLINE is true if we are reading the main symbol | |
562 | table (as opposed to a shared lib or dynamically loaded file). | |
563 | ||
564 | This function only does the minimum work necessary for letting the | |
565 | user "name" things symbolically; it does not read the entire symtab. | |
566 | Instead, it reads the external and static symbols and puts them in partial | |
567 | symbol tables. When more extensive information is requested of a | |
568 | file, the corresponding partial symbol table is mutated into a full | |
569 | fledged symbol table by going back and reading the symbols | |
570 | for real. | |
571 | ||
572 | We look for sections with specific names, to tell us what debug | |
573 | format to look for: FIXME!!! | |
574 | ||
575 | dwarf_build_psymtabs() builds psymtabs for DWARF symbols; | |
576 | elfstab_build_psymtabs() handles STABS symbols; | |
577 | mdebug_build_psymtabs() handles ECOFF debugging information. | |
578 | ||
579 | Note that ELF files have a "minimal" symbol table, which looks a lot | |
580 | like a COFF symbol table, but has only the minimal information necessary | |
581 | for linking. We process this also, and use the information to | |
582 | build gdb's minimal symbol table. This gives us some minimal debugging | |
583 | capability even for files compiled without -g. */ | |
584 | ||
585 | static void | |
96baa820 | 586 | elf_symfile_read (objfile, mainline) |
c906108c | 587 | struct objfile *objfile; |
c906108c SS |
588 | int mainline; |
589 | { | |
590 | bfd *abfd = objfile->obfd; | |
591 | struct elfinfo ei; | |
592 | struct cleanup *back_to; | |
593 | CORE_ADDR offset; | |
594 | ||
595 | init_minimal_symbol_collection (); | |
596 | back_to = make_cleanup ((make_cleanup_func) discard_minimal_symbols, 0); | |
597 | ||
598 | memset ((char *) &ei, 0, sizeof (ei)); | |
599 | ||
600 | /* Allocate struct to keep track of the symfile */ | |
601 | objfile->sym_stab_info = (struct dbx_symfile_info *) | |
c5aa993b | 602 | xmmalloc (objfile->md, sizeof (struct dbx_symfile_info)); |
c906108c SS |
603 | memset ((char *) objfile->sym_stab_info, 0, sizeof (struct dbx_symfile_info)); |
604 | make_cleanup (free_elfinfo, (PTR) objfile); | |
605 | ||
606 | /* Process the normal ELF symbol table first. This may write some | |
607 | chain of info into the dbx_symfile_info in objfile->sym_stab_info, | |
608 | which can later be used by elfstab_offset_sections. */ | |
609 | ||
d4f3574e | 610 | elf_symtab_read (objfile, 0); |
c906108c SS |
611 | |
612 | /* Add the dynamic symbols. */ | |
613 | ||
d4f3574e | 614 | elf_symtab_read (objfile, 1); |
c906108c SS |
615 | |
616 | /* Now process debugging information, which is contained in | |
617 | special ELF sections. */ | |
618 | ||
619 | /* If we are reinitializing, or if we have never loaded syms yet, | |
620 | set table to empty. MAINLINE is cleared so that *_read_psymtab | |
621 | functions do not all also re-initialize the psymbol table. */ | |
622 | if (mainline) | |
623 | { | |
624 | init_psymbol_list (objfile, 0); | |
625 | mainline = 0; | |
626 | } | |
627 | ||
628 | /* We first have to find them... */ | |
c5aa993b | 629 | bfd_map_over_sections (abfd, elf_locate_sections, (PTR) & ei); |
c906108c SS |
630 | |
631 | /* ELF debugging information is inserted into the psymtab in the | |
632 | order of least informative first - most informative last. Since | |
633 | the psymtab table is searched `most recent insertion first' this | |
634 | increases the probability that more detailed debug information | |
635 | for a section is found. | |
636 | ||
637 | For instance, an object file might contain both .mdebug (XCOFF) | |
638 | and .debug_info (DWARF2) sections then .mdebug is inserted first | |
639 | (searched last) and DWARF2 is inserted last (searched first). If | |
640 | we don't do this then the XCOFF info is found first - for code in | |
641 | an included file XCOFF info is useless. */ | |
642 | ||
643 | if (ei.mdebugsect) | |
644 | { | |
645 | const struct ecoff_debug_swap *swap; | |
646 | ||
647 | /* .mdebug section, presumably holding ECOFF debugging | |
c5aa993b | 648 | information. */ |
c906108c SS |
649 | swap = get_elf_backend_data (abfd)->elf_backend_ecoff_debug_swap; |
650 | if (swap) | |
d4f3574e | 651 | elfmdebug_build_psymtabs (objfile, swap, ei.mdebugsect); |
c906108c SS |
652 | } |
653 | if (ei.stabsect) | |
654 | { | |
655 | asection *str_sect; | |
656 | ||
657 | /* Stab sections have an associated string table that looks like | |
c5aa993b | 658 | a separate section. */ |
c906108c SS |
659 | str_sect = bfd_get_section_by_name (abfd, ".stabstr"); |
660 | ||
661 | /* FIXME should probably warn about a stab section without a stabstr. */ | |
662 | if (str_sect) | |
663 | elfstab_build_psymtabs (objfile, | |
c906108c SS |
664 | mainline, |
665 | ei.stabsect->filepos, | |
666 | bfd_section_size (abfd, ei.stabsect), | |
667 | str_sect->filepos, | |
668 | bfd_section_size (abfd, str_sect)); | |
669 | } | |
670 | if (dwarf2_has_info (abfd)) | |
671 | { | |
672 | /* DWARF 2 sections */ | |
d4f3574e | 673 | dwarf2_build_psymtabs (objfile, mainline); |
c906108c SS |
674 | } |
675 | else if (ei.dboffset && ei.lnoffset) | |
676 | { | |
677 | /* DWARF sections */ | |
678 | dwarf_build_psymtabs (objfile, | |
d4f3574e | 679 | mainline, |
c906108c SS |
680 | ei.dboffset, ei.dbsize, |
681 | ei.lnoffset, ei.lnsize); | |
682 | } | |
683 | ||
684 | /* Install any minimal symbols that have been collected as the current | |
685 | minimal symbols for this objfile. */ | |
686 | ||
687 | install_minimal_symbols (objfile); | |
688 | ||
689 | do_cleanups (back_to); | |
690 | } | |
691 | ||
692 | /* This cleans up the objfile's sym_stab_info pointer, and the chain of | |
693 | stab_section_info's, that might be dangling from it. */ | |
694 | ||
695 | static void | |
696 | free_elfinfo (objp) | |
697 | PTR objp; | |
698 | { | |
c5aa993b | 699 | struct objfile *objfile = (struct objfile *) objp; |
c906108c SS |
700 | struct dbx_symfile_info *dbxinfo = objfile->sym_stab_info; |
701 | struct stab_section_info *ssi, *nssi; | |
702 | ||
703 | ssi = dbxinfo->stab_section_info; | |
704 | while (ssi) | |
705 | { | |
706 | nssi = ssi->next; | |
707 | mfree (objfile->md, ssi); | |
708 | ssi = nssi; | |
709 | } | |
710 | ||
711 | dbxinfo->stab_section_info = 0; /* Just say No mo info about this. */ | |
712 | } | |
713 | ||
714 | ||
715 | /* Initialize anything that needs initializing when a completely new symbol | |
716 | file is specified (not just adding some symbols from another file, e.g. a | |
717 | shared library). | |
718 | ||
719 | We reinitialize buildsym, since we may be reading stabs from an ELF file. */ | |
720 | ||
721 | static void | |
722 | elf_new_init (ignore) | |
723 | struct objfile *ignore; | |
724 | { | |
725 | stabsread_new_init (); | |
726 | buildsym_new_init (); | |
727 | } | |
728 | ||
729 | /* Perform any local cleanups required when we are done with a particular | |
730 | objfile. I.E, we are in the process of discarding all symbol information | |
731 | for an objfile, freeing up all memory held for it, and unlinking the | |
732 | objfile struct from the global list of known objfiles. */ | |
733 | ||
734 | static void | |
735 | elf_symfile_finish (objfile) | |
736 | struct objfile *objfile; | |
737 | { | |
c5aa993b | 738 | if (objfile->sym_stab_info != NULL) |
c906108c | 739 | { |
c5aa993b | 740 | mfree (objfile->md, objfile->sym_stab_info); |
c906108c SS |
741 | } |
742 | } | |
743 | ||
744 | /* ELF specific initialization routine for reading symbols. | |
745 | ||
746 | It is passed a pointer to a struct sym_fns which contains, among other | |
747 | things, the BFD for the file whose symbols are being read, and a slot for | |
748 | a pointer to "private data" which we can fill with goodies. | |
749 | ||
750 | For now at least, we have nothing in particular to do, so this function is | |
751 | just a stub. */ | |
752 | ||
753 | static void | |
754 | elf_symfile_init (objfile) | |
755 | struct objfile *objfile; | |
756 | { | |
757 | /* ELF objects may be reordered, so set OBJF_REORDERED. If we | |
758 | find this causes a significant slowdown in gdb then we could | |
759 | set it in the debug symbol readers only when necessary. */ | |
760 | objfile->flags |= OBJF_REORDERED; | |
761 | } | |
762 | ||
763 | /* When handling an ELF file that contains Sun STABS debug info, | |
764 | some of the debug info is relative to the particular chunk of the | |
765 | section that was generated in its individual .o file. E.g. | |
766 | offsets to static variables are relative to the start of the data | |
767 | segment *for that module before linking*. This information is | |
768 | painfully squirreled away in the ELF symbol table as local symbols | |
769 | with wierd names. Go get 'em when needed. */ | |
770 | ||
771 | void | |
772 | elfstab_offset_sections (objfile, pst) | |
773 | struct objfile *objfile; | |
774 | struct partial_symtab *pst; | |
775 | { | |
776 | char *filename = pst->filename; | |
777 | struct dbx_symfile_info *dbx = objfile->sym_stab_info; | |
778 | struct stab_section_info *maybe = dbx->stab_section_info; | |
779 | struct stab_section_info *questionable = 0; | |
780 | int i; | |
781 | char *p; | |
782 | ||
783 | /* The ELF symbol info doesn't include path names, so strip the path | |
784 | (if any) from the psymtab filename. */ | |
785 | while (0 != (p = strchr (filename, '/'))) | |
c5aa993b | 786 | filename = p + 1; |
c906108c SS |
787 | |
788 | /* FIXME: This linear search could speed up significantly | |
789 | if it was chained in the right order to match how we search it, | |
790 | and if we unchained when we found a match. */ | |
791 | for (; maybe; maybe = maybe->next) | |
792 | { | |
793 | if (filename[0] == maybe->filename[0] | |
794 | && STREQ (filename, maybe->filename)) | |
795 | { | |
796 | /* We found a match. But there might be several source files | |
797 | (from different directories) with the same name. */ | |
798 | if (0 == maybe->found) | |
799 | break; | |
c5aa993b | 800 | questionable = maybe; /* Might use it later. */ |
c906108c SS |
801 | } |
802 | } | |
803 | ||
804 | if (maybe == 0 && questionable != 0) | |
805 | { | |
806 | complain (&stab_info_questionable_complaint, filename); | |
807 | maybe = questionable; | |
808 | } | |
809 | ||
810 | if (maybe) | |
811 | { | |
812 | /* Found it! Allocate a new psymtab struct, and fill it in. */ | |
813 | maybe->found++; | |
814 | pst->section_offsets = (struct section_offsets *) | |
96baa820 | 815 | obstack_alloc (&objfile->psymbol_obstack, SIZEOF_SECTION_OFFSETS); |
c906108c SS |
816 | for (i = 0; i < SECT_OFF_MAX; i++) |
817 | ANOFFSET (pst->section_offsets, i) = maybe->sections[i]; | |
818 | return; | |
819 | } | |
820 | ||
821 | /* We were unable to find any offsets for this file. Complain. */ | |
c5aa993b | 822 | if (dbx->stab_section_info) /* If there *is* any info, */ |
c906108c SS |
823 | complain (&stab_info_mismatch_complaint, filename); |
824 | } | |
825 | \f | |
826 | /* Register that we are able to handle ELF object file formats. */ | |
827 | ||
828 | static struct sym_fns elf_sym_fns = | |
829 | { | |
830 | bfd_target_elf_flavour, | |
c5aa993b JM |
831 | elf_new_init, /* sym_new_init: init anything gbl to entire symtab */ |
832 | elf_symfile_init, /* sym_init: read initial info, setup for sym_read() */ | |
833 | elf_symfile_read, /* sym_read: read a symbol file into symtab */ | |
834 | elf_symfile_finish, /* sym_finish: finished with file, cleanup */ | |
96baa820 | 835 | default_symfile_offsets, /* sym_offsets: Translate ext. to int. relocation */ |
c5aa993b | 836 | NULL /* next: pointer to next struct sym_fns */ |
c906108c SS |
837 | }; |
838 | ||
839 | void | |
840 | _initialize_elfread () | |
841 | { | |
842 | add_symtab_fns (&elf_sym_fns); | |
843 | } |