Commit | Line | Data |
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c906108c | 1 | /* Read ELF (Executable and Linking Format) object files for GDB. |
1bac305b | 2 | |
6aba47ca | 3 | Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, |
9b254dd1 DJ |
4 | 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008 |
5 | Free Software Foundation, Inc. | |
1bac305b | 6 | |
c906108c SS |
7 | Written by Fred Fish at Cygnus Support. |
8 | ||
c5aa993b | 9 | This file is part of GDB. |
c906108c | 10 | |
c5aa993b JM |
11 | This program is free software; you can redistribute it and/or modify |
12 | it under the terms of the GNU General Public License as published by | |
a9762ec7 | 13 | the Free Software Foundation; either version 3 of the License, or |
c5aa993b | 14 | (at your option) any later version. |
c906108c | 15 | |
c5aa993b JM |
16 | This program is distributed in the hope that it will be useful, |
17 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
18 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
19 | GNU General Public License for more details. | |
c906108c | 20 | |
c5aa993b | 21 | You should have received a copy of the GNU General Public License |
a9762ec7 | 22 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
c906108c SS |
23 | |
24 | #include "defs.h" | |
25 | #include "bfd.h" | |
26 | #include "gdb_string.h" | |
27 | #include "elf-bfd.h" | |
31d99776 DJ |
28 | #include "elf/common.h" |
29 | #include "elf/internal.h" | |
c906108c SS |
30 | #include "elf/mips.h" |
31 | #include "symtab.h" | |
32 | #include "symfile.h" | |
33 | #include "objfiles.h" | |
34 | #include "buildsym.h" | |
35 | #include "stabsread.h" | |
36 | #include "gdb-stabs.h" | |
37 | #include "complaints.h" | |
38 | #include "demangle.h" | |
39 | ||
a14ed312 | 40 | extern void _initialize_elfread (void); |
392a587b | 41 | |
c906108c | 42 | /* The struct elfinfo is available only during ELF symbol table and |
6426a772 | 43 | psymtab reading. It is destroyed at the completion of psymtab-reading. |
c906108c SS |
44 | It's local to elf_symfile_read. */ |
45 | ||
c5aa993b JM |
46 | struct elfinfo |
47 | { | |
c5aa993b JM |
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 | 52 | |
12b9c64f | 53 | static void free_elfinfo (void *); |
c906108c | 54 | |
31d99776 DJ |
55 | /* Locate the segments in ABFD. */ |
56 | ||
57 | static struct symfile_segment_data * | |
58 | elf_symfile_segments (bfd *abfd) | |
59 | { | |
60 | Elf_Internal_Phdr *phdrs, **segments; | |
61 | long phdrs_size; | |
62 | int num_phdrs, num_segments, num_sections, i; | |
63 | asection *sect; | |
64 | struct symfile_segment_data *data; | |
65 | ||
66 | phdrs_size = bfd_get_elf_phdr_upper_bound (abfd); | |
67 | if (phdrs_size == -1) | |
68 | return NULL; | |
69 | ||
70 | phdrs = alloca (phdrs_size); | |
71 | num_phdrs = bfd_get_elf_phdrs (abfd, phdrs); | |
72 | if (num_phdrs == -1) | |
73 | return NULL; | |
74 | ||
75 | num_segments = 0; | |
76 | segments = alloca (sizeof (Elf_Internal_Phdr *) * num_phdrs); | |
77 | for (i = 0; i < num_phdrs; i++) | |
78 | if (phdrs[i].p_type == PT_LOAD) | |
79 | segments[num_segments++] = &phdrs[i]; | |
80 | ||
81 | if (num_segments == 0) | |
82 | return NULL; | |
83 | ||
84 | data = XZALLOC (struct symfile_segment_data); | |
85 | data->num_segments = num_segments; | |
86 | data->segment_bases = XCALLOC (num_segments, CORE_ADDR); | |
87 | data->segment_sizes = XCALLOC (num_segments, CORE_ADDR); | |
88 | ||
89 | for (i = 0; i < num_segments; i++) | |
90 | { | |
91 | data->segment_bases[i] = segments[i]->p_vaddr; | |
92 | data->segment_sizes[i] = segments[i]->p_memsz; | |
93 | } | |
94 | ||
95 | num_sections = bfd_count_sections (abfd); | |
96 | data->segment_info = XCALLOC (num_sections, int); | |
97 | ||
98 | for (i = 0, sect = abfd->sections; sect != NULL; i++, sect = sect->next) | |
99 | { | |
100 | int j; | |
101 | CORE_ADDR vma; | |
102 | ||
103 | if ((bfd_get_section_flags (abfd, sect) & SEC_ALLOC) == 0) | |
104 | continue; | |
105 | ||
106 | vma = bfd_get_section_vma (abfd, sect); | |
107 | ||
108 | for (j = 0; j < num_segments; j++) | |
109 | if (segments[j]->p_memsz > 0 | |
110 | && vma >= segments[j]->p_vaddr | |
111 | && vma < segments[j]->p_vaddr + segments[j]->p_memsz) | |
112 | { | |
113 | data->segment_info[i] = j + 1; | |
114 | break; | |
115 | } | |
116 | ||
117 | if (bfd_get_section_size (sect) > 0 && j == num_segments) | |
118 | warning (_("Loadable segment \"%s\" outside of ELF segments"), | |
119 | bfd_section_name (abfd, sect)); | |
120 | } | |
121 | ||
122 | return data; | |
123 | } | |
124 | ||
c906108c SS |
125 | /* We are called once per section from elf_symfile_read. We |
126 | need to examine each section we are passed, check to see | |
127 | if it is something we are interested in processing, and | |
128 | if so, stash away some access information for the section. | |
129 | ||
130 | For now we recognize the dwarf debug information sections and | |
131 | line number sections from matching their section names. The | |
132 | ELF definition is no real help here since it has no direct | |
133 | knowledge of DWARF (by design, so any debugging format can be | |
134 | used). | |
135 | ||
136 | We also recognize the ".stab" sections used by the Sun compilers | |
137 | released with Solaris 2. | |
138 | ||
139 | FIXME: The section names should not be hardwired strings (what | |
140 | should they be? I don't think most object file formats have enough | |
141 | section flags to specify what kind of debug section it is | |
142 | -kingdon). */ | |
143 | ||
144 | static void | |
12b9c64f | 145 | elf_locate_sections (bfd *ignore_abfd, asection *sectp, void *eip) |
c906108c | 146 | { |
52f0bd74 | 147 | struct elfinfo *ei; |
c906108c SS |
148 | |
149 | ei = (struct elfinfo *) eip; | |
7ce59000 | 150 | if (strcmp (sectp->name, ".stab") == 0) |
c906108c | 151 | { |
c5aa993b | 152 | ei->stabsect = sectp; |
c906108c | 153 | } |
6314a349 | 154 | else if (strcmp (sectp->name, ".stab.index") == 0) |
c906108c | 155 | { |
c5aa993b | 156 | ei->stabindexsect = sectp; |
c906108c | 157 | } |
6314a349 | 158 | else if (strcmp (sectp->name, ".mdebug") == 0) |
c906108c | 159 | { |
c5aa993b | 160 | ei->mdebugsect = sectp; |
c906108c SS |
161 | } |
162 | } | |
163 | ||
c906108c | 164 | static struct minimal_symbol * |
f594e5e9 MC |
165 | record_minimal_symbol (char *name, CORE_ADDR address, |
166 | enum minimal_symbol_type ms_type, | |
167 | asection *bfd_section, struct objfile *objfile) | |
c906108c | 168 | { |
bbeae047 | 169 | if (ms_type == mst_text || ms_type == mst_file_text) |
260edbc2 | 170 | address = gdbarch_smash_text_address (current_gdbarch, address); |
c906108c SS |
171 | |
172 | return prim_record_minimal_symbol_and_info | |
f594e5e9 | 173 | (name, address, ms_type, NULL, bfd_section->index, bfd_section, objfile); |
c906108c SS |
174 | } |
175 | ||
176 | /* | |
177 | ||
c5aa993b | 178 | LOCAL FUNCTION |
c906108c | 179 | |
c5aa993b | 180 | elf_symtab_read -- read the symbol table of an ELF file |
c906108c | 181 | |
c5aa993b | 182 | SYNOPSIS |
c906108c | 183 | |
6f610d07 | 184 | void elf_symtab_read (struct objfile *objfile, int type, |
62553543 | 185 | long number_of_symbols, asymbol **symbol_table) |
c906108c | 186 | |
c5aa993b | 187 | DESCRIPTION |
c906108c | 188 | |
62553543 | 189 | Given an objfile, a symbol table, and a flag indicating whether the |
6f610d07 UW |
190 | symbol table contains regular, dynamic, or synthetic symbols, add all |
191 | the global function and data symbols to the minimal symbol table. | |
c906108c | 192 | |
c5aa993b JM |
193 | In stabs-in-ELF, as implemented by Sun, there are some local symbols |
194 | defined in the ELF symbol table, which can be used to locate | |
195 | the beginnings of sections from each ".o" file that was linked to | |
196 | form the executable objfile. We gather any such info and record it | |
197 | in data structures hung off the objfile's private data. | |
c906108c | 198 | |
c5aa993b | 199 | */ |
c906108c | 200 | |
6f610d07 UW |
201 | #define ST_REGULAR 0 |
202 | #define ST_DYNAMIC 1 | |
203 | #define ST_SYNTHETIC 2 | |
204 | ||
c906108c | 205 | static void |
6f610d07 | 206 | elf_symtab_read (struct objfile *objfile, int type, |
62553543 | 207 | long number_of_symbols, asymbol **symbol_table) |
c906108c SS |
208 | { |
209 | long storage_needed; | |
210 | asymbol *sym; | |
c906108c | 211 | long i; |
c906108c | 212 | CORE_ADDR symaddr; |
d4f3574e | 213 | CORE_ADDR offset; |
c906108c SS |
214 | enum minimal_symbol_type ms_type; |
215 | /* If sectinfo is nonNULL, it contains section info that should end up | |
216 | filed in the objfile. */ | |
217 | struct stab_section_info *sectinfo = NULL; | |
218 | /* If filesym is nonzero, it points to a file symbol, but we haven't | |
219 | seen any section info for it yet. */ | |
220 | asymbol *filesym = 0; | |
4a146b47 EZ |
221 | /* Name of filesym, as saved on the objfile_obstack. */ |
222 | char *filesymname = obsavestring ("", 0, &objfile->objfile_obstack); | |
0a6ddd08 | 223 | struct dbx_symfile_info *dbx = objfile->deprecated_sym_stab_info; |
d4f3574e | 224 | int stripped = (bfd_get_symcount (objfile->obfd) == 0); |
c5aa993b | 225 | |
0cc7b392 | 226 | for (i = 0; i < number_of_symbols; i++) |
c906108c | 227 | { |
0cc7b392 DJ |
228 | sym = symbol_table[i]; |
229 | if (sym->name == NULL || *sym->name == '\0') | |
c906108c | 230 | { |
0cc7b392 DJ |
231 | /* Skip names that don't exist (shouldn't happen), or names |
232 | that are null strings (may happen). */ | |
233 | continue; | |
234 | } | |
c906108c | 235 | |
74763737 DJ |
236 | /* Skip "special" symbols, e.g. ARM mapping symbols. These are |
237 | symbols which do not correspond to objects in the symbol table, | |
238 | but have some other target-specific meaning. */ | |
239 | if (bfd_is_target_special_symbol (objfile->obfd, sym)) | |
240 | continue; | |
241 | ||
0cc7b392 | 242 | offset = ANOFFSET (objfile->section_offsets, sym->section->index); |
6f610d07 | 243 | if (type == ST_DYNAMIC |
0cc7b392 DJ |
244 | && sym->section == &bfd_und_section |
245 | && (sym->flags & BSF_FUNCTION)) | |
246 | { | |
247 | struct minimal_symbol *msym; | |
02c75f72 UW |
248 | bfd *abfd = objfile->obfd; |
249 | asection *sect; | |
0cc7b392 DJ |
250 | |
251 | /* Symbol is a reference to a function defined in | |
252 | a shared library. | |
253 | If its value is non zero then it is usually the address | |
254 | of the corresponding entry in the procedure linkage table, | |
255 | plus the desired section offset. | |
256 | If its value is zero then the dynamic linker has to resolve | |
257 | the symbol. We are unable to find any meaningful address | |
258 | for this symbol in the executable file, so we skip it. */ | |
259 | symaddr = sym->value; | |
260 | if (symaddr == 0) | |
261 | continue; | |
02c75f72 UW |
262 | |
263 | /* sym->section is the undefined section. However, we want to | |
264 | record the section where the PLT stub resides with the | |
265 | minimal symbol. Search the section table for the one that | |
266 | covers the stub's address. */ | |
267 | for (sect = abfd->sections; sect != NULL; sect = sect->next) | |
268 | { | |
269 | if ((bfd_get_section_flags (abfd, sect) & SEC_ALLOC) == 0) | |
270 | continue; | |
271 | ||
272 | if (symaddr >= bfd_get_section_vma (abfd, sect) | |
273 | && symaddr < bfd_get_section_vma (abfd, sect) | |
274 | + bfd_get_section_size (sect)) | |
275 | break; | |
276 | } | |
277 | if (!sect) | |
278 | continue; | |
279 | ||
280 | symaddr += ANOFFSET (objfile->section_offsets, sect->index); | |
281 | ||
0cc7b392 | 282 | msym = record_minimal_symbol |
02c75f72 | 283 | ((char *) sym->name, symaddr, mst_solib_trampoline, sect, objfile); |
0cc7b392 DJ |
284 | if (msym != NULL) |
285 | msym->filename = filesymname; | |
0cc7b392 DJ |
286 | continue; |
287 | } | |
c906108c | 288 | |
0cc7b392 DJ |
289 | /* If it is a nonstripped executable, do not enter dynamic |
290 | symbols, as the dynamic symbol table is usually a subset | |
291 | of the main symbol table. */ | |
6f610d07 | 292 | if (type == ST_DYNAMIC && !stripped) |
0cc7b392 DJ |
293 | continue; |
294 | if (sym->flags & BSF_FILE) | |
295 | { | |
296 | /* STT_FILE debugging symbol that helps stabs-in-elf debugging. | |
297 | Chain any old one onto the objfile; remember new sym. */ | |
298 | if (sectinfo != NULL) | |
c906108c | 299 | { |
0cc7b392 DJ |
300 | sectinfo->next = dbx->stab_section_info; |
301 | dbx->stab_section_info = sectinfo; | |
302 | sectinfo = NULL; | |
303 | } | |
304 | filesym = sym; | |
0cc7b392 DJ |
305 | filesymname = |
306 | obsavestring ((char *) filesym->name, strlen (filesym->name), | |
307 | &objfile->objfile_obstack); | |
0cc7b392 DJ |
308 | } |
309 | else if (sym->flags & BSF_SECTION_SYM) | |
310 | continue; | |
311 | else if (sym->flags & (BSF_GLOBAL | BSF_LOCAL | BSF_WEAK)) | |
312 | { | |
313 | struct minimal_symbol *msym; | |
314 | ||
315 | /* Select global/local/weak symbols. Note that bfd puts abs | |
316 | symbols in their own section, so all symbols we are | |
317 | interested in will have a section. */ | |
318 | /* Bfd symbols are section relative. */ | |
319 | symaddr = sym->value + sym->section->vma; | |
320 | /* Relocate all non-absolute symbols by the section offset. */ | |
321 | if (sym->section != &bfd_abs_section) | |
322 | { | |
323 | symaddr += offset; | |
c906108c | 324 | } |
0cc7b392 DJ |
325 | /* For non-absolute symbols, use the type of the section |
326 | they are relative to, to intuit text/data. Bfd provides | |
327 | no way of figuring this out for absolute symbols. */ | |
328 | if (sym->section == &bfd_abs_section) | |
c906108c | 329 | { |
0cc7b392 DJ |
330 | /* This is a hack to get the minimal symbol type |
331 | right for Irix 5, which has absolute addresses | |
6f610d07 UW |
332 | with special section indices for dynamic symbols. |
333 | ||
334 | NOTE: uweigand-20071112: Synthetic symbols do not | |
335 | have an ELF-private part, so do not touch those. */ | |
4fbb74a6 | 336 | unsigned int shndx = type == ST_SYNTHETIC ? 0 : |
0cc7b392 DJ |
337 | ((elf_symbol_type *) sym)->internal_elf_sym.st_shndx; |
338 | ||
339 | switch (shndx) | |
c906108c | 340 | { |
0cc7b392 DJ |
341 | case SHN_MIPS_TEXT: |
342 | ms_type = mst_text; | |
343 | break; | |
344 | case SHN_MIPS_DATA: | |
345 | ms_type = mst_data; | |
346 | break; | |
347 | case SHN_MIPS_ACOMMON: | |
348 | ms_type = mst_bss; | |
349 | break; | |
350 | default: | |
351 | ms_type = mst_abs; | |
352 | } | |
353 | ||
354 | /* If it is an Irix dynamic symbol, skip section name | |
355 | symbols, relocate all others by section offset. */ | |
356 | if (ms_type != mst_abs) | |
357 | { | |
358 | if (sym->name[0] == '.') | |
359 | continue; | |
d4f3574e | 360 | symaddr += offset; |
c906108c | 361 | } |
0cc7b392 DJ |
362 | } |
363 | else if (sym->section->flags & SEC_CODE) | |
364 | { | |
08232497 | 365 | if (sym->flags & (BSF_GLOBAL | BSF_WEAK)) |
c906108c | 366 | { |
0cc7b392 DJ |
367 | ms_type = mst_text; |
368 | } | |
369 | else if ((sym->name[0] == '.' && sym->name[1] == 'L') | |
370 | || ((sym->flags & BSF_LOCAL) | |
371 | && sym->name[0] == '$' | |
372 | && sym->name[1] == 'L')) | |
373 | /* Looks like a compiler-generated label. Skip | |
374 | it. The assembler should be skipping these (to | |
375 | keep executables small), but apparently with | |
376 | gcc on the (deleted) delta m88k SVR4, it loses. | |
377 | So to have us check too should be harmless (but | |
378 | I encourage people to fix this in the assembler | |
379 | instead of adding checks here). */ | |
380 | continue; | |
381 | else | |
382 | { | |
383 | ms_type = mst_file_text; | |
c906108c | 384 | } |
0cc7b392 DJ |
385 | } |
386 | else if (sym->section->flags & SEC_ALLOC) | |
387 | { | |
388 | if (sym->flags & (BSF_GLOBAL | BSF_WEAK)) | |
c906108c | 389 | { |
0cc7b392 | 390 | if (sym->section->flags & SEC_LOAD) |
c906108c | 391 | { |
0cc7b392 | 392 | ms_type = mst_data; |
c906108c | 393 | } |
c906108c SS |
394 | else |
395 | { | |
0cc7b392 | 396 | ms_type = mst_bss; |
c906108c SS |
397 | } |
398 | } | |
0cc7b392 | 399 | else if (sym->flags & BSF_LOCAL) |
c906108c | 400 | { |
0cc7b392 DJ |
401 | /* Named Local variable in a Data section. |
402 | Check its name for stabs-in-elf. */ | |
403 | int special_local_sect; | |
404 | if (strcmp ("Bbss.bss", sym->name) == 0) | |
405 | special_local_sect = SECT_OFF_BSS (objfile); | |
406 | else if (strcmp ("Ddata.data", sym->name) == 0) | |
407 | special_local_sect = SECT_OFF_DATA (objfile); | |
408 | else if (strcmp ("Drodata.rodata", sym->name) == 0) | |
409 | special_local_sect = SECT_OFF_RODATA (objfile); | |
410 | else | |
411 | special_local_sect = -1; | |
412 | if (special_local_sect >= 0) | |
c906108c | 413 | { |
0cc7b392 DJ |
414 | /* Found a special local symbol. Allocate a |
415 | sectinfo, if needed, and fill it in. */ | |
416 | if (sectinfo == NULL) | |
c906108c | 417 | { |
0cc7b392 DJ |
418 | int max_index; |
419 | size_t size; | |
420 | ||
421 | max_index | |
422 | = max (SECT_OFF_BSS (objfile), | |
423 | max (SECT_OFF_DATA (objfile), | |
424 | SECT_OFF_RODATA (objfile))); | |
425 | ||
426 | /* max_index is the largest index we'll | |
427 | use into this array, so we must | |
428 | allocate max_index+1 elements for it. | |
429 | However, 'struct stab_section_info' | |
430 | already includes one element, so we | |
431 | need to allocate max_index aadditional | |
432 | elements. */ | |
433 | size = (sizeof (struct stab_section_info) | |
434 | + (sizeof (CORE_ADDR) | |
435 | * max_index)); | |
436 | sectinfo = (struct stab_section_info *) | |
437 | xmalloc (size); | |
438 | memset (sectinfo, 0, size); | |
439 | sectinfo->num_sections = max_index; | |
440 | if (filesym == NULL) | |
c906108c | 441 | { |
0cc7b392 DJ |
442 | complaint (&symfile_complaints, |
443 | _("elf/stab section information %s without a preceding file symbol"), | |
444 | sym->name); | |
445 | } | |
446 | else | |
447 | { | |
448 | sectinfo->filename = | |
449 | (char *) filesym->name; | |
c906108c | 450 | } |
c906108c | 451 | } |
0cc7b392 DJ |
452 | if (sectinfo->sections[special_local_sect] != 0) |
453 | complaint (&symfile_complaints, | |
454 | _("duplicated elf/stab section information for %s"), | |
455 | sectinfo->filename); | |
456 | /* BFD symbols are section relative. */ | |
457 | symaddr = sym->value + sym->section->vma; | |
458 | /* Relocate non-absolute symbols by the | |
459 | section offset. */ | |
460 | if (sym->section != &bfd_abs_section) | |
461 | symaddr += offset; | |
462 | sectinfo->sections[special_local_sect] = symaddr; | |
463 | /* The special local symbols don't go in the | |
464 | minimal symbol table, so ignore this one. */ | |
465 | continue; | |
466 | } | |
467 | /* Not a special stabs-in-elf symbol, do regular | |
468 | symbol processing. */ | |
469 | if (sym->section->flags & SEC_LOAD) | |
470 | { | |
471 | ms_type = mst_file_data; | |
c906108c SS |
472 | } |
473 | else | |
474 | { | |
0cc7b392 | 475 | ms_type = mst_file_bss; |
c906108c SS |
476 | } |
477 | } | |
478 | else | |
479 | { | |
0cc7b392 | 480 | ms_type = mst_unknown; |
c906108c | 481 | } |
0cc7b392 DJ |
482 | } |
483 | else | |
484 | { | |
485 | /* FIXME: Solaris2 shared libraries include lots of | |
486 | odd "absolute" and "undefined" symbols, that play | |
487 | hob with actions like finding what function the PC | |
488 | is in. Ignore them if they aren't text, data, or bss. */ | |
489 | /* ms_type = mst_unknown; */ | |
490 | continue; /* Skip this symbol. */ | |
491 | } | |
492 | msym = record_minimal_symbol | |
493 | ((char *) sym->name, symaddr, | |
494 | ms_type, sym->section, objfile); | |
6f610d07 | 495 | |
0cc7b392 DJ |
496 | if (msym) |
497 | { | |
498 | /* Pass symbol size field in via BFD. FIXME!!! */ | |
6f610d07 UW |
499 | elf_symbol_type *elf_sym; |
500 | ||
501 | /* NOTE: uweigand-20071112: A synthetic symbol does not have an | |
502 | ELF-private part. However, in some cases (e.g. synthetic | |
503 | 'dot' symbols on ppc64) the udata.p entry is set to point back | |
504 | to the original ELF symbol it was derived from. Get the size | |
505 | from that symbol. */ | |
506 | if (type != ST_SYNTHETIC) | |
507 | elf_sym = (elf_symbol_type *) sym; | |
508 | else | |
509 | elf_sym = (elf_symbol_type *) sym->udata.p; | |
510 | ||
511 | if (elf_sym) | |
512 | MSYMBOL_SIZE(msym) = elf_sym->internal_elf_sym.st_size; | |
0cc7b392 | 513 | } |
0cc7b392 DJ |
514 | if (msym != NULL) |
515 | msym->filename = filesymname; | |
95f1da47 | 516 | gdbarch_elf_make_msymbol_special (current_gdbarch, sym, msym); |
c906108c | 517 | } |
c906108c SS |
518 | } |
519 | } | |
520 | ||
521 | /* Scan and build partial symbols for a symbol file. | |
522 | We have been initialized by a call to elf_symfile_init, which | |
523 | currently does nothing. | |
524 | ||
525 | SECTION_OFFSETS is a set of offsets to apply to relocate the symbols | |
526 | in each section. We simplify it down to a single offset for all | |
527 | symbols. FIXME. | |
528 | ||
529 | MAINLINE is true if we are reading the main symbol | |
530 | table (as opposed to a shared lib or dynamically loaded file). | |
531 | ||
532 | This function only does the minimum work necessary for letting the | |
533 | user "name" things symbolically; it does not read the entire symtab. | |
534 | Instead, it reads the external and static symbols and puts them in partial | |
535 | symbol tables. When more extensive information is requested of a | |
536 | file, the corresponding partial symbol table is mutated into a full | |
537 | fledged symbol table by going back and reading the symbols | |
538 | for real. | |
539 | ||
540 | We look for sections with specific names, to tell us what debug | |
541 | format to look for: FIXME!!! | |
542 | ||
c906108c SS |
543 | elfstab_build_psymtabs() handles STABS symbols; |
544 | mdebug_build_psymtabs() handles ECOFF debugging information. | |
545 | ||
546 | Note that ELF files have a "minimal" symbol table, which looks a lot | |
547 | like a COFF symbol table, but has only the minimal information necessary | |
548 | for linking. We process this also, and use the information to | |
549 | build gdb's minimal symbol table. This gives us some minimal debugging | |
550 | capability even for files compiled without -g. */ | |
551 | ||
552 | static void | |
fba45db2 | 553 | elf_symfile_read (struct objfile *objfile, int mainline) |
c906108c SS |
554 | { |
555 | bfd *abfd = objfile->obfd; | |
556 | struct elfinfo ei; | |
557 | struct cleanup *back_to; | |
558 | CORE_ADDR offset; | |
62553543 EZ |
559 | long symcount = 0, dynsymcount = 0, synthcount, storage_needed; |
560 | asymbol **symbol_table = NULL, **dyn_symbol_table = NULL; | |
561 | asymbol *synthsyms; | |
c906108c SS |
562 | |
563 | init_minimal_symbol_collection (); | |
56e290f4 | 564 | back_to = make_cleanup_discard_minimal_symbols (); |
c906108c SS |
565 | |
566 | memset ((char *) &ei, 0, sizeof (ei)); | |
567 | ||
568 | /* Allocate struct to keep track of the symfile */ | |
0a6ddd08 | 569 | objfile->deprecated_sym_stab_info = (struct dbx_symfile_info *) |
7936743b | 570 | xmalloc (sizeof (struct dbx_symfile_info)); |
0a6ddd08 | 571 | memset ((char *) objfile->deprecated_sym_stab_info, 0, sizeof (struct dbx_symfile_info)); |
12b9c64f | 572 | make_cleanup (free_elfinfo, (void *) objfile); |
c906108c SS |
573 | |
574 | /* Process the normal ELF symbol table first. This may write some | |
0a6ddd08 | 575 | chain of info into the dbx_symfile_info in objfile->deprecated_sym_stab_info, |
c906108c SS |
576 | which can later be used by elfstab_offset_sections. */ |
577 | ||
62553543 EZ |
578 | storage_needed = bfd_get_symtab_upper_bound (objfile->obfd); |
579 | if (storage_needed < 0) | |
580 | error (_("Can't read symbols from %s: %s"), bfd_get_filename (objfile->obfd), | |
581 | bfd_errmsg (bfd_get_error ())); | |
582 | ||
583 | if (storage_needed > 0) | |
584 | { | |
585 | symbol_table = (asymbol **) xmalloc (storage_needed); | |
586 | make_cleanup (xfree, symbol_table); | |
587 | symcount = bfd_canonicalize_symtab (objfile->obfd, symbol_table); | |
588 | ||
589 | if (symcount < 0) | |
590 | error (_("Can't read symbols from %s: %s"), bfd_get_filename (objfile->obfd), | |
591 | bfd_errmsg (bfd_get_error ())); | |
592 | ||
6f610d07 | 593 | elf_symtab_read (objfile, ST_REGULAR, symcount, symbol_table); |
62553543 | 594 | } |
c906108c SS |
595 | |
596 | /* Add the dynamic symbols. */ | |
597 | ||
62553543 EZ |
598 | storage_needed = bfd_get_dynamic_symtab_upper_bound (objfile->obfd); |
599 | ||
600 | if (storage_needed > 0) | |
601 | { | |
602 | dyn_symbol_table = (asymbol **) xmalloc (storage_needed); | |
603 | make_cleanup (xfree, dyn_symbol_table); | |
604 | dynsymcount = bfd_canonicalize_dynamic_symtab (objfile->obfd, | |
605 | dyn_symbol_table); | |
606 | ||
607 | if (dynsymcount < 0) | |
608 | error (_("Can't read symbols from %s: %s"), bfd_get_filename (objfile->obfd), | |
609 | bfd_errmsg (bfd_get_error ())); | |
610 | ||
6f610d07 | 611 | elf_symtab_read (objfile, ST_DYNAMIC, dynsymcount, dyn_symbol_table); |
62553543 EZ |
612 | } |
613 | ||
614 | /* Add synthetic symbols - for instance, names for any PLT entries. */ | |
615 | ||
616 | synthcount = bfd_get_synthetic_symtab (abfd, symcount, symbol_table, | |
617 | dynsymcount, dyn_symbol_table, | |
618 | &synthsyms); | |
619 | if (synthcount > 0) | |
620 | { | |
621 | asymbol **synth_symbol_table; | |
622 | long i; | |
623 | ||
624 | make_cleanup (xfree, synthsyms); | |
625 | synth_symbol_table = xmalloc (sizeof (asymbol *) * synthcount); | |
626 | for (i = 0; i < synthcount; i++) | |
9f20e3da | 627 | synth_symbol_table[i] = synthsyms + i; |
62553543 | 628 | make_cleanup (xfree, synth_symbol_table); |
6f610d07 | 629 | elf_symtab_read (objfile, ST_SYNTHETIC, synthcount, synth_symbol_table); |
62553543 | 630 | } |
c906108c | 631 | |
7134143f DJ |
632 | /* Install any minimal symbols that have been collected as the current |
633 | minimal symbols for this objfile. The debug readers below this point | |
634 | should not generate new minimal symbols; if they do it's their | |
635 | responsibility to install them. "mdebug" appears to be the only one | |
636 | which will do this. */ | |
637 | ||
638 | install_minimal_symbols (objfile); | |
639 | do_cleanups (back_to); | |
640 | ||
c906108c SS |
641 | /* Now process debugging information, which is contained in |
642 | special ELF sections. */ | |
643 | ||
644 | /* If we are reinitializing, or if we have never loaded syms yet, | |
645 | set table to empty. MAINLINE is cleared so that *_read_psymtab | |
646 | functions do not all also re-initialize the psymbol table. */ | |
647 | if (mainline) | |
648 | { | |
649 | init_psymbol_list (objfile, 0); | |
650 | mainline = 0; | |
651 | } | |
652 | ||
653 | /* We first have to find them... */ | |
12b9c64f | 654 | bfd_map_over_sections (abfd, elf_locate_sections, (void *) & ei); |
c906108c SS |
655 | |
656 | /* ELF debugging information is inserted into the psymtab in the | |
657 | order of least informative first - most informative last. Since | |
658 | the psymtab table is searched `most recent insertion first' this | |
659 | increases the probability that more detailed debug information | |
660 | for a section is found. | |
661 | ||
662 | For instance, an object file might contain both .mdebug (XCOFF) | |
663 | and .debug_info (DWARF2) sections then .mdebug is inserted first | |
664 | (searched last) and DWARF2 is inserted last (searched first). If | |
665 | we don't do this then the XCOFF info is found first - for code in | |
666 | an included file XCOFF info is useless. */ | |
667 | ||
668 | if (ei.mdebugsect) | |
669 | { | |
670 | const struct ecoff_debug_swap *swap; | |
671 | ||
672 | /* .mdebug section, presumably holding ECOFF debugging | |
c5aa993b | 673 | information. */ |
c906108c SS |
674 | swap = get_elf_backend_data (abfd)->elf_backend_ecoff_debug_swap; |
675 | if (swap) | |
d4f3574e | 676 | elfmdebug_build_psymtabs (objfile, swap, ei.mdebugsect); |
c906108c SS |
677 | } |
678 | if (ei.stabsect) | |
679 | { | |
680 | asection *str_sect; | |
681 | ||
682 | /* Stab sections have an associated string table that looks like | |
c5aa993b | 683 | a separate section. */ |
c906108c SS |
684 | str_sect = bfd_get_section_by_name (abfd, ".stabstr"); |
685 | ||
686 | /* FIXME should probably warn about a stab section without a stabstr. */ | |
687 | if (str_sect) | |
688 | elfstab_build_psymtabs (objfile, | |
c906108c | 689 | mainline, |
086df311 | 690 | ei.stabsect, |
c906108c SS |
691 | str_sect->filepos, |
692 | bfd_section_size (abfd, str_sect)); | |
693 | } | |
c5edf76a | 694 | if (dwarf2_has_info (objfile)) |
c906108c SS |
695 | { |
696 | /* DWARF 2 sections */ | |
d4f3574e | 697 | dwarf2_build_psymtabs (objfile, mainline); |
c906108c | 698 | } |
c906108c | 699 | |
625b0b97 AC |
700 | /* FIXME: kettenis/20030504: This still needs to be integrated with |
701 | dwarf2read.c in a better way. */ | |
702 | dwarf2_build_frame_info (objfile); | |
c906108c SS |
703 | } |
704 | ||
0a6ddd08 AC |
705 | /* This cleans up the objfile's deprecated_sym_stab_info pointer, and |
706 | the chain of stab_section_info's, that might be dangling from | |
707 | it. */ | |
c906108c SS |
708 | |
709 | static void | |
12b9c64f | 710 | free_elfinfo (void *objp) |
c906108c | 711 | { |
c5aa993b | 712 | struct objfile *objfile = (struct objfile *) objp; |
0a6ddd08 | 713 | struct dbx_symfile_info *dbxinfo = objfile->deprecated_sym_stab_info; |
c906108c SS |
714 | struct stab_section_info *ssi, *nssi; |
715 | ||
716 | ssi = dbxinfo->stab_section_info; | |
717 | while (ssi) | |
718 | { | |
719 | nssi = ssi->next; | |
2dc74dc1 | 720 | xfree (ssi); |
c906108c SS |
721 | ssi = nssi; |
722 | } | |
723 | ||
724 | dbxinfo->stab_section_info = 0; /* Just say No mo info about this. */ | |
725 | } | |
726 | ||
727 | ||
728 | /* Initialize anything that needs initializing when a completely new symbol | |
729 | file is specified (not just adding some symbols from another file, e.g. a | |
730 | shared library). | |
731 | ||
732 | We reinitialize buildsym, since we may be reading stabs from an ELF file. */ | |
733 | ||
734 | static void | |
fba45db2 | 735 | elf_new_init (struct objfile *ignore) |
c906108c SS |
736 | { |
737 | stabsread_new_init (); | |
738 | buildsym_new_init (); | |
739 | } | |
740 | ||
741 | /* Perform any local cleanups required when we are done with a particular | |
742 | objfile. I.E, we are in the process of discarding all symbol information | |
743 | for an objfile, freeing up all memory held for it, and unlinking the | |
744 | objfile struct from the global list of known objfiles. */ | |
745 | ||
746 | static void | |
fba45db2 | 747 | elf_symfile_finish (struct objfile *objfile) |
c906108c | 748 | { |
0a6ddd08 | 749 | if (objfile->deprecated_sym_stab_info != NULL) |
c906108c | 750 | { |
0a6ddd08 | 751 | xfree (objfile->deprecated_sym_stab_info); |
c906108c | 752 | } |
fe3e1990 DJ |
753 | |
754 | dwarf2_free_objfile (objfile); | |
c906108c SS |
755 | } |
756 | ||
757 | /* ELF specific initialization routine for reading symbols. | |
758 | ||
759 | It is passed a pointer to a struct sym_fns which contains, among other | |
760 | things, the BFD for the file whose symbols are being read, and a slot for | |
761 | a pointer to "private data" which we can fill with goodies. | |
762 | ||
763 | For now at least, we have nothing in particular to do, so this function is | |
764 | just a stub. */ | |
765 | ||
766 | static void | |
fba45db2 | 767 | elf_symfile_init (struct objfile *objfile) |
c906108c SS |
768 | { |
769 | /* ELF objects may be reordered, so set OBJF_REORDERED. If we | |
770 | find this causes a significant slowdown in gdb then we could | |
771 | set it in the debug symbol readers only when necessary. */ | |
772 | objfile->flags |= OBJF_REORDERED; | |
773 | } | |
774 | ||
775 | /* When handling an ELF file that contains Sun STABS debug info, | |
776 | some of the debug info is relative to the particular chunk of the | |
777 | section that was generated in its individual .o file. E.g. | |
778 | offsets to static variables are relative to the start of the data | |
779 | segment *for that module before linking*. This information is | |
780 | painfully squirreled away in the ELF symbol table as local symbols | |
781 | with wierd names. Go get 'em when needed. */ | |
782 | ||
783 | void | |
fba45db2 | 784 | elfstab_offset_sections (struct objfile *objfile, struct partial_symtab *pst) |
c906108c SS |
785 | { |
786 | char *filename = pst->filename; | |
0a6ddd08 | 787 | struct dbx_symfile_info *dbx = objfile->deprecated_sym_stab_info; |
c906108c SS |
788 | struct stab_section_info *maybe = dbx->stab_section_info; |
789 | struct stab_section_info *questionable = 0; | |
790 | int i; | |
791 | char *p; | |
792 | ||
793 | /* The ELF symbol info doesn't include path names, so strip the path | |
794 | (if any) from the psymtab filename. */ | |
795 | while (0 != (p = strchr (filename, '/'))) | |
c5aa993b | 796 | filename = p + 1; |
c906108c SS |
797 | |
798 | /* FIXME: This linear search could speed up significantly | |
799 | if it was chained in the right order to match how we search it, | |
800 | and if we unchained when we found a match. */ | |
801 | for (; maybe; maybe = maybe->next) | |
802 | { | |
803 | if (filename[0] == maybe->filename[0] | |
6314a349 | 804 | && strcmp (filename, maybe->filename) == 0) |
c906108c SS |
805 | { |
806 | /* We found a match. But there might be several source files | |
807 | (from different directories) with the same name. */ | |
808 | if (0 == maybe->found) | |
809 | break; | |
c5aa993b | 810 | questionable = maybe; /* Might use it later. */ |
c906108c SS |
811 | } |
812 | } | |
813 | ||
814 | if (maybe == 0 && questionable != 0) | |
815 | { | |
23136709 | 816 | complaint (&symfile_complaints, |
e2e0b3e5 | 817 | _("elf/stab section information questionable for %s"), filename); |
c906108c SS |
818 | maybe = questionable; |
819 | } | |
820 | ||
821 | if (maybe) | |
822 | { | |
823 | /* Found it! Allocate a new psymtab struct, and fill it in. */ | |
824 | maybe->found++; | |
825 | pst->section_offsets = (struct section_offsets *) | |
8b92e4d5 | 826 | obstack_alloc (&objfile->objfile_obstack, |
a39a16c4 MM |
827 | SIZEOF_N_SECTION_OFFSETS (objfile->num_sections)); |
828 | for (i = 0; i < maybe->num_sections; i++) | |
a4c8257b | 829 | (pst->section_offsets)->offsets[i] = maybe->sections[i]; |
c906108c SS |
830 | return; |
831 | } | |
832 | ||
833 | /* We were unable to find any offsets for this file. Complain. */ | |
c5aa993b | 834 | if (dbx->stab_section_info) /* If there *is* any info, */ |
23136709 | 835 | complaint (&symfile_complaints, |
e2e0b3e5 | 836 | _("elf/stab section information missing for %s"), filename); |
c906108c SS |
837 | } |
838 | \f | |
839 | /* Register that we are able to handle ELF object file formats. */ | |
840 | ||
841 | static struct sym_fns elf_sym_fns = | |
842 | { | |
843 | bfd_target_elf_flavour, | |
c5aa993b JM |
844 | elf_new_init, /* sym_new_init: init anything gbl to entire symtab */ |
845 | elf_symfile_init, /* sym_init: read initial info, setup for sym_read() */ | |
846 | elf_symfile_read, /* sym_read: read a symbol file into symtab */ | |
847 | elf_symfile_finish, /* sym_finish: finished with file, cleanup */ | |
96baa820 | 848 | default_symfile_offsets, /* sym_offsets: Translate ext. to int. relocation */ |
31d99776 DJ |
849 | elf_symfile_segments, /* sym_segments: Get segment information from |
850 | a file. */ | |
c295b2e5 | 851 | NULL, /* sym_read_linetable */ |
c5aa993b | 852 | NULL /* next: pointer to next struct sym_fns */ |
c906108c SS |
853 | }; |
854 | ||
855 | void | |
fba45db2 | 856 | _initialize_elfread (void) |
c906108c SS |
857 | { |
858 | add_symtab_fns (&elf_sym_fns); | |
859 | } |