Commit | Line | Data |
---|---|---|
c906108c | 1 | /* Read ELF (Executable and Linking Format) object files for GDB. |
b6ba6518 | 2 | Copyright 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, |
181c1381 | 3 | 2001, 2002 |
8e65ff28 | 4 | Free Software Foundation, Inc. |
c906108c SS |
5 | Written by Fred Fish at Cygnus Support. |
6 | ||
c5aa993b | 7 | This file is part of GDB. |
c906108c | 8 | |
c5aa993b JM |
9 | This program is free software; you can redistribute it and/or modify |
10 | it under the terms of the GNU General Public License as published by | |
11 | the Free Software Foundation; either version 2 of the License, or | |
12 | (at your option) any later version. | |
c906108c | 13 | |
c5aa993b JM |
14 | This program is distributed in the hope that it will be useful, |
15 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
16 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
17 | GNU General Public License for more details. | |
c906108c | 18 | |
c5aa993b JM |
19 | You should have received a copy of the GNU General Public License |
20 | along with this program; if not, write to the Free Software | |
21 | Foundation, Inc., 59 Temple Place - Suite 330, | |
22 | Boston, MA 02111-1307, USA. */ | |
c906108c SS |
23 | |
24 | #include "defs.h" | |
25 | #include "bfd.h" | |
26 | #include "gdb_string.h" | |
27 | #include "elf-bfd.h" | |
28 | #include "elf/mips.h" | |
29 | #include "symtab.h" | |
30 | #include "symfile.h" | |
31 | #include "objfiles.h" | |
32 | #include "buildsym.h" | |
33 | #include "stabsread.h" | |
34 | #include "gdb-stabs.h" | |
35 | #include "complaints.h" | |
36 | #include "demangle.h" | |
37 | ||
a14ed312 | 38 | extern void _initialize_elfread (void); |
392a587b | 39 | |
c906108c | 40 | /* The struct elfinfo is available only during ELF symbol table and |
6426a772 | 41 | psymtab reading. It is destroyed at the completion of psymtab-reading. |
c906108c SS |
42 | It's local to elf_symfile_read. */ |
43 | ||
c5aa993b JM |
44 | struct elfinfo |
45 | { | |
46 | file_ptr dboffset; /* Offset to dwarf debug section */ | |
47 | unsigned int dbsize; /* Size of dwarf debug section */ | |
48 | file_ptr lnoffset; /* Offset to dwarf line number section */ | |
49 | unsigned int lnsize; /* Size of dwarf line number section */ | |
50 | asection *stabsect; /* Section pointer for .stab section */ | |
51 | asection *stabindexsect; /* Section pointer for .stab.index section */ | |
52 | asection *mdebugsect; /* Section pointer for .mdebug section */ | |
53 | }; | |
c906108c | 54 | |
12b9c64f | 55 | static void free_elfinfo (void *); |
c906108c SS |
56 | |
57 | /* We are called once per section from elf_symfile_read. We | |
58 | need to examine each section we are passed, check to see | |
59 | if it is something we are interested in processing, and | |
60 | if so, stash away some access information for the section. | |
61 | ||
62 | For now we recognize the dwarf debug information sections and | |
63 | line number sections from matching their section names. The | |
64 | ELF definition is no real help here since it has no direct | |
65 | knowledge of DWARF (by design, so any debugging format can be | |
66 | used). | |
67 | ||
68 | We also recognize the ".stab" sections used by the Sun compilers | |
69 | released with Solaris 2. | |
70 | ||
71 | FIXME: The section names should not be hardwired strings (what | |
72 | should they be? I don't think most object file formats have enough | |
73 | section flags to specify what kind of debug section it is | |
74 | -kingdon). */ | |
75 | ||
76 | static void | |
12b9c64f | 77 | elf_locate_sections (bfd *ignore_abfd, asection *sectp, void *eip) |
c906108c SS |
78 | { |
79 | register struct elfinfo *ei; | |
80 | ||
81 | ei = (struct elfinfo *) eip; | |
c5aa993b | 82 | if (STREQ (sectp->name, ".debug")) |
c906108c | 83 | { |
c5aa993b JM |
84 | ei->dboffset = sectp->filepos; |
85 | ei->dbsize = bfd_get_section_size_before_reloc (sectp); | |
c906108c | 86 | } |
c5aa993b | 87 | else if (STREQ (sectp->name, ".line")) |
c906108c | 88 | { |
c5aa993b JM |
89 | ei->lnoffset = sectp->filepos; |
90 | ei->lnsize = bfd_get_section_size_before_reloc (sectp); | |
c906108c | 91 | } |
c5aa993b | 92 | else if (STREQ (sectp->name, ".stab")) |
c906108c | 93 | { |
c5aa993b | 94 | ei->stabsect = sectp; |
c906108c | 95 | } |
c5aa993b | 96 | else if (STREQ (sectp->name, ".stab.index")) |
c906108c | 97 | { |
c5aa993b | 98 | ei->stabindexsect = sectp; |
c906108c | 99 | } |
c5aa993b | 100 | else if (STREQ (sectp->name, ".mdebug")) |
c906108c | 101 | { |
c5aa993b | 102 | ei->mdebugsect = sectp; |
c906108c SS |
103 | } |
104 | } | |
105 | ||
c5aa993b | 106 | #if 0 /* Currently unused */ |
c906108c SS |
107 | |
108 | char * | |
fba45db2 | 109 | elf_interpreter (bfd *abfd) |
c906108c SS |
110 | { |
111 | sec_ptr interp_sec; | |
112 | unsigned size; | |
113 | char *interp = NULL; | |
114 | ||
115 | interp_sec = bfd_get_section_by_name (abfd, ".interp"); | |
116 | if (interp_sec) | |
117 | { | |
118 | size = bfd_section_size (abfd, interp_sec); | |
119 | interp = alloca (size); | |
c5aa993b | 120 | if (bfd_get_section_contents (abfd, interp_sec, interp, (file_ptr) 0, |
c906108c SS |
121 | size)) |
122 | { | |
123 | interp = savestring (interp, size - 1); | |
124 | } | |
125 | else | |
126 | { | |
127 | interp = NULL; | |
128 | } | |
129 | } | |
130 | return (interp); | |
131 | } | |
132 | ||
133 | #endif | |
134 | ||
135 | static struct minimal_symbol * | |
fba45db2 KB |
136 | record_minimal_symbol_and_info (char *name, CORE_ADDR address, |
137 | enum minimal_symbol_type ms_type, char *info, /* FIXME, is this really char *? */ | |
138 | asection *bfd_section, struct objfile *objfile) | |
c906108c | 139 | { |
bbeae047 | 140 | if (ms_type == mst_text || ms_type == mst_file_text) |
181c1381 | 141 | address = SMASH_TEXT_ADDRESS (address); |
c906108c SS |
142 | |
143 | return prim_record_minimal_symbol_and_info | |
bbeae047 | 144 | (name, address, ms_type, info, bfd_section->index, bfd_section, objfile); |
c906108c SS |
145 | } |
146 | ||
147 | /* | |
148 | ||
c5aa993b | 149 | LOCAL FUNCTION |
c906108c | 150 | |
c5aa993b | 151 | elf_symtab_read -- read the symbol table of an ELF file |
c906108c | 152 | |
c5aa993b | 153 | SYNOPSIS |
c906108c | 154 | |
d4f3574e | 155 | void elf_symtab_read (struct objfile *objfile, int dynamic) |
c906108c | 156 | |
c5aa993b | 157 | DESCRIPTION |
c906108c | 158 | |
d4f3574e SS |
159 | Given an objfile and a flag that specifies whether or not the objfile |
160 | is for an executable or not (may be shared library for example), add | |
161 | all the global function and data symbols to the minimal symbol table. | |
c906108c | 162 | |
c5aa993b JM |
163 | In stabs-in-ELF, as implemented by Sun, there are some local symbols |
164 | defined in the ELF symbol table, which can be used to locate | |
165 | the beginnings of sections from each ".o" file that was linked to | |
166 | form the executable objfile. We gather any such info and record it | |
167 | in data structures hung off the objfile's private data. | |
c906108c | 168 | |
c5aa993b | 169 | */ |
c906108c SS |
170 | |
171 | static void | |
fba45db2 | 172 | elf_symtab_read (struct objfile *objfile, int dynamic) |
c906108c SS |
173 | { |
174 | long storage_needed; | |
175 | asymbol *sym; | |
176 | asymbol **symbol_table; | |
177 | long number_of_symbols; | |
178 | long i; | |
179 | int index; | |
180 | struct cleanup *back_to; | |
181 | CORE_ADDR symaddr; | |
d4f3574e | 182 | CORE_ADDR offset; |
c906108c SS |
183 | enum minimal_symbol_type ms_type; |
184 | /* If sectinfo is nonNULL, it contains section info that should end up | |
185 | filed in the objfile. */ | |
186 | struct stab_section_info *sectinfo = NULL; | |
187 | /* If filesym is nonzero, it points to a file symbol, but we haven't | |
188 | seen any section info for it yet. */ | |
189 | asymbol *filesym = 0; | |
190 | #ifdef SOFUN_ADDRESS_MAYBE_MISSING | |
191 | /* Name of filesym, as saved on the symbol_obstack. */ | |
192 | char *filesymname = obsavestring ("", 0, &objfile->symbol_obstack); | |
193 | #endif | |
194 | struct dbx_symfile_info *dbx = objfile->sym_stab_info; | |
195 | unsigned long size; | |
d4f3574e | 196 | int stripped = (bfd_get_symcount (objfile->obfd) == 0); |
c5aa993b | 197 | |
c906108c SS |
198 | if (dynamic) |
199 | { | |
d4f3574e | 200 | storage_needed = bfd_get_dynamic_symtab_upper_bound (objfile->obfd); |
c906108c SS |
201 | |
202 | /* Nothing to be done if there is no dynamic symtab. */ | |
203 | if (storage_needed < 0) | |
204 | return; | |
205 | } | |
206 | else | |
207 | { | |
d4f3574e | 208 | storage_needed = bfd_get_symtab_upper_bound (objfile->obfd); |
c906108c | 209 | if (storage_needed < 0) |
d4f3574e | 210 | error ("Can't read symbols from %s: %s", bfd_get_filename (objfile->obfd), |
c906108c SS |
211 | bfd_errmsg (bfd_get_error ())); |
212 | } | |
213 | if (storage_needed > 0) | |
214 | { | |
215 | symbol_table = (asymbol **) xmalloc (storage_needed); | |
b8c9b27d | 216 | back_to = make_cleanup (xfree, symbol_table); |
c906108c | 217 | if (dynamic) |
d4f3574e | 218 | number_of_symbols = bfd_canonicalize_dynamic_symtab (objfile->obfd, |
c906108c SS |
219 | symbol_table); |
220 | else | |
d4f3574e | 221 | number_of_symbols = bfd_canonicalize_symtab (objfile->obfd, symbol_table); |
c906108c | 222 | if (number_of_symbols < 0) |
d4f3574e | 223 | error ("Can't read symbols from %s: %s", bfd_get_filename (objfile->obfd), |
c906108c | 224 | bfd_errmsg (bfd_get_error ())); |
b8d39351 | 225 | |
c906108c SS |
226 | for (i = 0; i < number_of_symbols; i++) |
227 | { | |
228 | sym = symbol_table[i]; | |
c5aa993b | 229 | if (sym->name == NULL || *sym->name == '\0') |
c906108c SS |
230 | { |
231 | /* Skip names that don't exist (shouldn't happen), or names | |
c5aa993b | 232 | that are null strings (may happen). */ |
c906108c SS |
233 | continue; |
234 | } | |
235 | ||
b8d39351 | 236 | offset = ANOFFSET (objfile->section_offsets, sym->section->index); |
c906108c | 237 | if (dynamic |
c5aa993b JM |
238 | && sym->section == &bfd_und_section |
239 | && (sym->flags & BSF_FUNCTION)) | |
c906108c SS |
240 | { |
241 | struct minimal_symbol *msym; | |
242 | ||
243 | /* Symbol is a reference to a function defined in | |
c5aa993b JM |
244 | a shared library. |
245 | If its value is non zero then it is usually the address | |
246 | of the corresponding entry in the procedure linkage table, | |
d4f3574e | 247 | plus the desired section offset. |
c5aa993b JM |
248 | If its value is zero then the dynamic linker has to resolve |
249 | the symbol. We are unable to find any meaningful address | |
250 | for this symbol in the executable file, so we skip it. */ | |
251 | symaddr = sym->value; | |
c906108c SS |
252 | if (symaddr == 0) |
253 | continue; | |
d4f3574e | 254 | symaddr += offset; |
c906108c | 255 | msym = record_minimal_symbol_and_info |
c5aa993b JM |
256 | ((char *) sym->name, symaddr, |
257 | mst_solib_trampoline, NULL, sym->section, objfile); | |
c906108c SS |
258 | #ifdef SOFUN_ADDRESS_MAYBE_MISSING |
259 | if (msym != NULL) | |
260 | msym->filename = filesymname; | |
261 | #endif | |
262 | continue; | |
263 | } | |
264 | ||
265 | /* If it is a nonstripped executable, do not enter dynamic | |
266 | symbols, as the dynamic symbol table is usually a subset | |
267 | of the main symbol table. */ | |
268 | if (dynamic && !stripped) | |
269 | continue; | |
c5aa993b | 270 | if (sym->flags & BSF_FILE) |
c906108c SS |
271 | { |
272 | /* STT_FILE debugging symbol that helps stabs-in-elf debugging. | |
c5aa993b | 273 | Chain any old one onto the objfile; remember new sym. */ |
c906108c SS |
274 | if (sectinfo != NULL) |
275 | { | |
c5aa993b JM |
276 | sectinfo->next = dbx->stab_section_info; |
277 | dbx->stab_section_info = sectinfo; | |
c906108c SS |
278 | sectinfo = NULL; |
279 | } | |
280 | filesym = sym; | |
281 | #ifdef SOFUN_ADDRESS_MAYBE_MISSING | |
282 | filesymname = | |
c5aa993b | 283 | obsavestring ((char *) filesym->name, strlen (filesym->name), |
c906108c SS |
284 | &objfile->symbol_obstack); |
285 | #endif | |
286 | } | |
c5aa993b | 287 | else if (sym->flags & (BSF_GLOBAL | BSF_LOCAL | BSF_WEAK)) |
c906108c SS |
288 | { |
289 | struct minimal_symbol *msym; | |
290 | ||
291 | /* Select global/local/weak symbols. Note that bfd puts abs | |
c5aa993b JM |
292 | symbols in their own section, so all symbols we are |
293 | interested in will have a section. */ | |
c906108c | 294 | /* Bfd symbols are section relative. */ |
c5aa993b | 295 | symaddr = sym->value + sym->section->vma; |
d4f3574e | 296 | /* Relocate all non-absolute symbols by the section offset. */ |
c5aa993b | 297 | if (sym->section != &bfd_abs_section) |
c906108c | 298 | { |
d4f3574e | 299 | symaddr += offset; |
c906108c SS |
300 | } |
301 | /* For non-absolute symbols, use the type of the section | |
c5aa993b JM |
302 | they are relative to, to intuit text/data. Bfd provides |
303 | no way of figuring this out for absolute symbols. */ | |
304 | if (sym->section == &bfd_abs_section) | |
c906108c SS |
305 | { |
306 | /* This is a hack to get the minimal symbol type | |
11cf8741 | 307 | right for Irix 5, which has absolute addresses |
c906108c SS |
308 | with special section indices for dynamic symbols. */ |
309 | unsigned short shndx = | |
c5aa993b | 310 | ((elf_symbol_type *) sym)->internal_elf_sym.st_shndx; |
c906108c SS |
311 | |
312 | switch (shndx) | |
313 | { | |
314 | case SHN_MIPS_TEXT: | |
315 | ms_type = mst_text; | |
316 | break; | |
317 | case SHN_MIPS_DATA: | |
318 | ms_type = mst_data; | |
319 | break; | |
320 | case SHN_MIPS_ACOMMON: | |
321 | ms_type = mst_bss; | |
322 | break; | |
323 | default: | |
324 | ms_type = mst_abs; | |
325 | } | |
326 | ||
327 | /* If it is an Irix dynamic symbol, skip section name | |
d4f3574e | 328 | symbols, relocate all others by section offset. */ |
c906108c SS |
329 | if (ms_type != mst_abs) |
330 | { | |
331 | if (sym->name[0] == '.') | |
332 | continue; | |
d4f3574e | 333 | symaddr += offset; |
c906108c SS |
334 | } |
335 | } | |
c5aa993b | 336 | else if (sym->section->flags & SEC_CODE) |
c906108c | 337 | { |
389e51db | 338 | if (sym->flags & BSF_GLOBAL) |
c906108c SS |
339 | { |
340 | ms_type = mst_text; | |
341 | } | |
342 | else if ((sym->name[0] == '.' && sym->name[1] == 'L') | |
c5aa993b | 343 | || ((sym->flags & BSF_LOCAL) |
c906108c SS |
344 | && sym->name[0] == '$' |
345 | && sym->name[1] == 'L')) | |
7fb623f7 AC |
346 | /* Looks like a compiler-generated label. Skip |
347 | it. The assembler should be skipping these (to | |
348 | keep executables small), but apparently with | |
349 | gcc on the (OBSOLETE) delta m88k SVR4, it | |
350 | loses. So to have us check too should be | |
351 | harmless (but I encourage people to fix this in | |
352 | the assembler instead of adding checks here). */ | |
c906108c | 353 | continue; |
c906108c SS |
354 | else |
355 | { | |
356 | ms_type = mst_file_text; | |
357 | } | |
358 | } | |
c5aa993b | 359 | else if (sym->section->flags & SEC_ALLOC) |
c906108c | 360 | { |
bbeae047 | 361 | if (sym->flags & (BSF_GLOBAL | BSF_WEAK)) |
c906108c | 362 | { |
c5aa993b | 363 | if (sym->section->flags & SEC_LOAD) |
c906108c SS |
364 | { |
365 | ms_type = mst_data; | |
366 | } | |
367 | else | |
368 | { | |
369 | ms_type = mst_bss; | |
370 | } | |
371 | } | |
c5aa993b | 372 | else if (sym->flags & BSF_LOCAL) |
c906108c SS |
373 | { |
374 | /* Named Local variable in a Data section. Check its | |
c5aa993b JM |
375 | name for stabs-in-elf. The STREQ macro checks the |
376 | first character inline, so we only actually do a | |
377 | strcmp function call on names that start with 'B' | |
378 | or 'D' */ | |
c906108c | 379 | index = SECT_OFF_MAX; |
c5aa993b | 380 | if (STREQ ("Bbss.bss", sym->name)) |
c906108c | 381 | { |
b8fbeb18 | 382 | index = SECT_OFF_BSS (objfile); |
c906108c | 383 | } |
c5aa993b | 384 | else if (STREQ ("Ddata.data", sym->name)) |
c906108c | 385 | { |
b8fbeb18 | 386 | index = SECT_OFF_DATA (objfile); |
c906108c | 387 | } |
c5aa993b | 388 | else if (STREQ ("Drodata.rodata", sym->name)) |
c906108c | 389 | { |
b8fbeb18 | 390 | index = SECT_OFF_RODATA (objfile); |
c906108c SS |
391 | } |
392 | if (index != SECT_OFF_MAX) | |
393 | { | |
394 | /* Found a special local symbol. Allocate a | |
395 | sectinfo, if needed, and fill it in. */ | |
396 | if (sectinfo == NULL) | |
397 | { | |
398 | sectinfo = (struct stab_section_info *) | |
c5aa993b | 399 | xmmalloc (objfile->md, sizeof (*sectinfo)); |
12b9c64f AO |
400 | memset (sectinfo, 0, |
401 | sizeof (*sectinfo)); | |
c906108c SS |
402 | if (filesym == NULL) |
403 | { | |
23136709 KB |
404 | complaint (&symfile_complaints, |
405 | "elf/stab section information %s without a preceding file symbol", | |
406 | sym->name); | |
c906108c SS |
407 | } |
408 | else | |
409 | { | |
c5aa993b JM |
410 | sectinfo->filename = |
411 | (char *) filesym->name; | |
c906108c SS |
412 | } |
413 | } | |
a4c8257b EZ |
414 | if (index != -1) |
415 | { | |
416 | if (sectinfo->sections[index] != 0) | |
417 | { | |
23136709 KB |
418 | complaint (&symfile_complaints, |
419 | "duplicated elf/stab section information for %s", | |
420 | sectinfo->filename); | |
a4c8257b | 421 | } |
c906108c | 422 | } |
a4c8257b | 423 | else |
8e65ff28 AC |
424 | internal_error (__FILE__, __LINE__, |
425 | "Section index uninitialized."); | |
c906108c | 426 | /* Bfd symbols are section relative. */ |
c5aa993b | 427 | symaddr = sym->value + sym->section->vma; |
d4f3574e | 428 | /* Relocate non-absolute symbols by the section offset. */ |
c5aa993b | 429 | if (sym->section != &bfd_abs_section) |
c906108c | 430 | { |
d4f3574e | 431 | symaddr += offset; |
c906108c | 432 | } |
a4c8257b EZ |
433 | if (index != -1) |
434 | sectinfo->sections[index] = symaddr; | |
435 | else | |
8e65ff28 AC |
436 | internal_error (__FILE__, __LINE__, |
437 | "Section index uninitialized."); | |
c906108c SS |
438 | /* The special local symbols don't go in the |
439 | minimal symbol table, so ignore this one. */ | |
440 | continue; | |
441 | } | |
442 | /* Not a special stabs-in-elf symbol, do regular | |
c5aa993b JM |
443 | symbol processing. */ |
444 | if (sym->section->flags & SEC_LOAD) | |
c906108c SS |
445 | { |
446 | ms_type = mst_file_data; | |
447 | } | |
448 | else | |
449 | { | |
450 | ms_type = mst_file_bss; | |
451 | } | |
452 | } | |
453 | else | |
454 | { | |
455 | ms_type = mst_unknown; | |
456 | } | |
457 | } | |
458 | else | |
459 | { | |
460 | /* FIXME: Solaris2 shared libraries include lots of | |
461 | odd "absolute" and "undefined" symbols, that play | |
462 | hob with actions like finding what function the PC | |
463 | is in. Ignore them if they aren't text, data, or bss. */ | |
464 | /* ms_type = mst_unknown; */ | |
c5aa993b | 465 | continue; /* Skip this symbol. */ |
c906108c SS |
466 | } |
467 | /* Pass symbol size field in via BFD. FIXME!!! */ | |
c5aa993b | 468 | size = ((elf_symbol_type *) sym)->internal_elf_sym.st_size; |
c906108c | 469 | msym = record_minimal_symbol_and_info |
c5aa993b | 470 | ((char *) sym->name, symaddr, |
12b9c64f | 471 | ms_type, (void *) size, sym->section, objfile); |
c906108c SS |
472 | #ifdef SOFUN_ADDRESS_MAYBE_MISSING |
473 | if (msym != NULL) | |
474 | msym->filename = filesymname; | |
475 | #endif | |
c5aa993b | 476 | ELF_MAKE_MSYMBOL_SPECIAL (sym, msym); |
c906108c SS |
477 | } |
478 | } | |
479 | do_cleanups (back_to); | |
480 | } | |
481 | } | |
482 | ||
483 | /* Scan and build partial symbols for a symbol file. | |
484 | We have been initialized by a call to elf_symfile_init, which | |
485 | currently does nothing. | |
486 | ||
487 | SECTION_OFFSETS is a set of offsets to apply to relocate the symbols | |
488 | in each section. We simplify it down to a single offset for all | |
489 | symbols. FIXME. | |
490 | ||
491 | MAINLINE is true if we are reading the main symbol | |
492 | table (as opposed to a shared lib or dynamically loaded file). | |
493 | ||
494 | This function only does the minimum work necessary for letting the | |
495 | user "name" things symbolically; it does not read the entire symtab. | |
496 | Instead, it reads the external and static symbols and puts them in partial | |
497 | symbol tables. When more extensive information is requested of a | |
498 | file, the corresponding partial symbol table is mutated into a full | |
499 | fledged symbol table by going back and reading the symbols | |
500 | for real. | |
501 | ||
502 | We look for sections with specific names, to tell us what debug | |
503 | format to look for: FIXME!!! | |
504 | ||
505 | dwarf_build_psymtabs() builds psymtabs for DWARF symbols; | |
506 | elfstab_build_psymtabs() handles STABS symbols; | |
507 | mdebug_build_psymtabs() handles ECOFF debugging information. | |
508 | ||
509 | Note that ELF files have a "minimal" symbol table, which looks a lot | |
510 | like a COFF symbol table, but has only the minimal information necessary | |
511 | for linking. We process this also, and use the information to | |
512 | build gdb's minimal symbol table. This gives us some minimal debugging | |
513 | capability even for files compiled without -g. */ | |
514 | ||
515 | static void | |
fba45db2 | 516 | elf_symfile_read (struct objfile *objfile, int mainline) |
c906108c SS |
517 | { |
518 | bfd *abfd = objfile->obfd; | |
519 | struct elfinfo ei; | |
520 | struct cleanup *back_to; | |
521 | CORE_ADDR offset; | |
522 | ||
523 | init_minimal_symbol_collection (); | |
56e290f4 | 524 | back_to = make_cleanup_discard_minimal_symbols (); |
c906108c SS |
525 | |
526 | memset ((char *) &ei, 0, sizeof (ei)); | |
527 | ||
528 | /* Allocate struct to keep track of the symfile */ | |
529 | objfile->sym_stab_info = (struct dbx_symfile_info *) | |
c5aa993b | 530 | xmmalloc (objfile->md, sizeof (struct dbx_symfile_info)); |
c906108c | 531 | memset ((char *) objfile->sym_stab_info, 0, sizeof (struct dbx_symfile_info)); |
12b9c64f | 532 | make_cleanup (free_elfinfo, (void *) objfile); |
c906108c SS |
533 | |
534 | /* Process the normal ELF symbol table first. This may write some | |
535 | chain of info into the dbx_symfile_info in objfile->sym_stab_info, | |
536 | which can later be used by elfstab_offset_sections. */ | |
537 | ||
d4f3574e | 538 | elf_symtab_read (objfile, 0); |
c906108c SS |
539 | |
540 | /* Add the dynamic symbols. */ | |
541 | ||
d4f3574e | 542 | elf_symtab_read (objfile, 1); |
c906108c SS |
543 | |
544 | /* Now process debugging information, which is contained in | |
545 | special ELF sections. */ | |
546 | ||
547 | /* If we are reinitializing, or if we have never loaded syms yet, | |
548 | set table to empty. MAINLINE is cleared so that *_read_psymtab | |
549 | functions do not all also re-initialize the psymbol table. */ | |
550 | if (mainline) | |
551 | { | |
552 | init_psymbol_list (objfile, 0); | |
553 | mainline = 0; | |
554 | } | |
555 | ||
556 | /* We first have to find them... */ | |
12b9c64f | 557 | bfd_map_over_sections (abfd, elf_locate_sections, (void *) & ei); |
c906108c SS |
558 | |
559 | /* ELF debugging information is inserted into the psymtab in the | |
560 | order of least informative first - most informative last. Since | |
561 | the psymtab table is searched `most recent insertion first' this | |
562 | increases the probability that more detailed debug information | |
563 | for a section is found. | |
564 | ||
565 | For instance, an object file might contain both .mdebug (XCOFF) | |
566 | and .debug_info (DWARF2) sections then .mdebug is inserted first | |
567 | (searched last) and DWARF2 is inserted last (searched first). If | |
568 | we don't do this then the XCOFF info is found first - for code in | |
569 | an included file XCOFF info is useless. */ | |
570 | ||
571 | if (ei.mdebugsect) | |
572 | { | |
573 | const struct ecoff_debug_swap *swap; | |
574 | ||
575 | /* .mdebug section, presumably holding ECOFF debugging | |
c5aa993b | 576 | information. */ |
c906108c SS |
577 | swap = get_elf_backend_data (abfd)->elf_backend_ecoff_debug_swap; |
578 | if (swap) | |
d4f3574e | 579 | elfmdebug_build_psymtabs (objfile, swap, ei.mdebugsect); |
c906108c SS |
580 | } |
581 | if (ei.stabsect) | |
582 | { | |
583 | asection *str_sect; | |
584 | ||
585 | /* Stab sections have an associated string table that looks like | |
c5aa993b | 586 | a separate section. */ |
c906108c SS |
587 | str_sect = bfd_get_section_by_name (abfd, ".stabstr"); |
588 | ||
589 | /* FIXME should probably warn about a stab section without a stabstr. */ | |
590 | if (str_sect) | |
591 | elfstab_build_psymtabs (objfile, | |
c906108c SS |
592 | mainline, |
593 | ei.stabsect->filepos, | |
594 | bfd_section_size (abfd, ei.stabsect), | |
595 | str_sect->filepos, | |
596 | bfd_section_size (abfd, str_sect)); | |
597 | } | |
598 | if (dwarf2_has_info (abfd)) | |
599 | { | |
600 | /* DWARF 2 sections */ | |
d4f3574e | 601 | dwarf2_build_psymtabs (objfile, mainline); |
c906108c SS |
602 | } |
603 | else if (ei.dboffset && ei.lnoffset) | |
604 | { | |
605 | /* DWARF sections */ | |
606 | dwarf_build_psymtabs (objfile, | |
d4f3574e | 607 | mainline, |
c906108c SS |
608 | ei.dboffset, ei.dbsize, |
609 | ei.lnoffset, ei.lnsize); | |
610 | } | |
611 | ||
b6af0555 JS |
612 | if (DWARF2_BUILD_FRAME_INFO_P ()) |
613 | DWARF2_BUILD_FRAME_INFO(objfile); | |
614 | ||
c906108c SS |
615 | /* Install any minimal symbols that have been collected as the current |
616 | minimal symbols for this objfile. */ | |
617 | ||
618 | install_minimal_symbols (objfile); | |
619 | ||
620 | do_cleanups (back_to); | |
621 | } | |
622 | ||
623 | /* This cleans up the objfile's sym_stab_info pointer, and the chain of | |
624 | stab_section_info's, that might be dangling from it. */ | |
625 | ||
626 | static void | |
12b9c64f | 627 | free_elfinfo (void *objp) |
c906108c | 628 | { |
c5aa993b | 629 | struct objfile *objfile = (struct objfile *) objp; |
c906108c SS |
630 | struct dbx_symfile_info *dbxinfo = objfile->sym_stab_info; |
631 | struct stab_section_info *ssi, *nssi; | |
632 | ||
633 | ssi = dbxinfo->stab_section_info; | |
634 | while (ssi) | |
635 | { | |
636 | nssi = ssi->next; | |
aac7f4ea | 637 | xmfree (objfile->md, ssi); |
c906108c SS |
638 | ssi = nssi; |
639 | } | |
640 | ||
641 | dbxinfo->stab_section_info = 0; /* Just say No mo info about this. */ | |
642 | } | |
643 | ||
644 | ||
645 | /* Initialize anything that needs initializing when a completely new symbol | |
646 | file is specified (not just adding some symbols from another file, e.g. a | |
647 | shared library). | |
648 | ||
649 | We reinitialize buildsym, since we may be reading stabs from an ELF file. */ | |
650 | ||
651 | static void | |
fba45db2 | 652 | elf_new_init (struct objfile *ignore) |
c906108c SS |
653 | { |
654 | stabsread_new_init (); | |
655 | buildsym_new_init (); | |
656 | } | |
657 | ||
658 | /* Perform any local cleanups required when we are done with a particular | |
659 | objfile. I.E, we are in the process of discarding all symbol information | |
660 | for an objfile, freeing up all memory held for it, and unlinking the | |
661 | objfile struct from the global list of known objfiles. */ | |
662 | ||
663 | static void | |
fba45db2 | 664 | elf_symfile_finish (struct objfile *objfile) |
c906108c | 665 | { |
c5aa993b | 666 | if (objfile->sym_stab_info != NULL) |
c906108c | 667 | { |
aac7f4ea | 668 | xmfree (objfile->md, objfile->sym_stab_info); |
c906108c SS |
669 | } |
670 | } | |
671 | ||
672 | /* ELF specific initialization routine for reading symbols. | |
673 | ||
674 | It is passed a pointer to a struct sym_fns which contains, among other | |
675 | things, the BFD for the file whose symbols are being read, and a slot for | |
676 | a pointer to "private data" which we can fill with goodies. | |
677 | ||
678 | For now at least, we have nothing in particular to do, so this function is | |
679 | just a stub. */ | |
680 | ||
681 | static void | |
fba45db2 | 682 | elf_symfile_init (struct objfile *objfile) |
c906108c SS |
683 | { |
684 | /* ELF objects may be reordered, so set OBJF_REORDERED. If we | |
685 | find this causes a significant slowdown in gdb then we could | |
686 | set it in the debug symbol readers only when necessary. */ | |
687 | objfile->flags |= OBJF_REORDERED; | |
688 | } | |
689 | ||
690 | /* When handling an ELF file that contains Sun STABS debug info, | |
691 | some of the debug info is relative to the particular chunk of the | |
692 | section that was generated in its individual .o file. E.g. | |
693 | offsets to static variables are relative to the start of the data | |
694 | segment *for that module before linking*. This information is | |
695 | painfully squirreled away in the ELF symbol table as local symbols | |
696 | with wierd names. Go get 'em when needed. */ | |
697 | ||
698 | void | |
fba45db2 | 699 | elfstab_offset_sections (struct objfile *objfile, struct partial_symtab *pst) |
c906108c SS |
700 | { |
701 | char *filename = pst->filename; | |
702 | struct dbx_symfile_info *dbx = objfile->sym_stab_info; | |
703 | struct stab_section_info *maybe = dbx->stab_section_info; | |
704 | struct stab_section_info *questionable = 0; | |
705 | int i; | |
706 | char *p; | |
707 | ||
708 | /* The ELF symbol info doesn't include path names, so strip the path | |
709 | (if any) from the psymtab filename. */ | |
710 | while (0 != (p = strchr (filename, '/'))) | |
c5aa993b | 711 | filename = p + 1; |
c906108c SS |
712 | |
713 | /* FIXME: This linear search could speed up significantly | |
714 | if it was chained in the right order to match how we search it, | |
715 | and if we unchained when we found a match. */ | |
716 | for (; maybe; maybe = maybe->next) | |
717 | { | |
718 | if (filename[0] == maybe->filename[0] | |
719 | && STREQ (filename, maybe->filename)) | |
720 | { | |
721 | /* We found a match. But there might be several source files | |
722 | (from different directories) with the same name. */ | |
723 | if (0 == maybe->found) | |
724 | break; | |
c5aa993b | 725 | questionable = maybe; /* Might use it later. */ |
c906108c SS |
726 | } |
727 | } | |
728 | ||
729 | if (maybe == 0 && questionable != 0) | |
730 | { | |
23136709 KB |
731 | complaint (&symfile_complaints, |
732 | "elf/stab section information questionable for %s", filename); | |
c906108c SS |
733 | maybe = questionable; |
734 | } | |
735 | ||
736 | if (maybe) | |
737 | { | |
738 | /* Found it! Allocate a new psymtab struct, and fill it in. */ | |
739 | maybe->found++; | |
740 | pst->section_offsets = (struct section_offsets *) | |
96baa820 | 741 | obstack_alloc (&objfile->psymbol_obstack, SIZEOF_SECTION_OFFSETS); |
c906108c | 742 | for (i = 0; i < SECT_OFF_MAX; i++) |
a4c8257b | 743 | (pst->section_offsets)->offsets[i] = maybe->sections[i]; |
c906108c SS |
744 | return; |
745 | } | |
746 | ||
747 | /* We were unable to find any offsets for this file. Complain. */ | |
c5aa993b | 748 | if (dbx->stab_section_info) /* If there *is* any info, */ |
23136709 KB |
749 | complaint (&symfile_complaints, |
750 | "elf/stab section information missing for %s", filename); | |
c906108c SS |
751 | } |
752 | \f | |
753 | /* Register that we are able to handle ELF object file formats. */ | |
754 | ||
755 | static struct sym_fns elf_sym_fns = | |
756 | { | |
757 | bfd_target_elf_flavour, | |
c5aa993b JM |
758 | elf_new_init, /* sym_new_init: init anything gbl to entire symtab */ |
759 | elf_symfile_init, /* sym_init: read initial info, setup for sym_read() */ | |
760 | elf_symfile_read, /* sym_read: read a symbol file into symtab */ | |
761 | elf_symfile_finish, /* sym_finish: finished with file, cleanup */ | |
96baa820 | 762 | default_symfile_offsets, /* sym_offsets: Translate ext. to int. relocation */ |
c5aa993b | 763 | NULL /* next: pointer to next struct sym_fns */ |
c906108c SS |
764 | }; |
765 | ||
766 | void | |
fba45db2 | 767 | _initialize_elfread (void) |
c906108c SS |
768 | { |
769 | add_symtab_fns (&elf_sym_fns); | |
770 | } |