Commit | Line | Data |
---|---|---|
c906108c | 1 | /* Read a symbol table in MIPS' format (Third-Eye). |
303d2914 | 2 | |
197e01b6 | 3 | Copyright (C) 1986, 1987, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, |
6aba47ca | 4 | 1998, 1999, 2000, 2001, 2003, 2004, 2007 Free Software Foundation, Inc. |
303d2914 | 5 | |
c906108c SS |
6 | Contributed by Alessandro Forin (af@cs.cmu.edu) at CMU. Major work |
7 | by Per Bothner, John Gilmore and Ian Lance Taylor 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 | /* Read symbols from an ECOFF file. Most of the work is done in | |
25 | mdebugread.c. */ | |
26 | ||
27 | #include "defs.h" | |
28 | #include "gdb_string.h" | |
29 | #include "bfd.h" | |
30 | #include "symtab.h" | |
c906108c SS |
31 | #include "objfiles.h" |
32 | #include "buildsym.h" | |
33 | #include "stabsread.h" | |
c906108c SS |
34 | |
35 | #include "coff/sym.h" | |
36 | #include "coff/internal.h" | |
37 | #include "coff/ecoff.h" | |
38 | #include "libcoff.h" /* Private BFD COFF information. */ | |
39 | #include "libecoff.h" /* Private BFD ECOFF information. */ | |
40 | #include "elf/common.h" | |
41 | #include "elf/mips.h" | |
42 | ||
c906108c | 43 | static void |
a14ed312 KB |
44 | read_alphacoff_dynamic_symtab (struct section_offsets *, |
45 | struct objfile *objfile); | |
c906108c SS |
46 | |
47 | /* Initialize anything that needs initializing when a completely new | |
48 | symbol file is specified (not just adding some symbols from another | |
49 | file, e.g. a shared library). */ | |
50 | ||
c906108c | 51 | static void |
fba45db2 | 52 | mipscoff_new_init (struct objfile *ignore) |
c906108c | 53 | { |
c906108c SS |
54 | stabsread_new_init (); |
55 | buildsym_new_init (); | |
56 | } | |
57 | ||
58 | /* Initialize to read a symbol file (nothing to do). */ | |
59 | ||
60 | static void | |
fba45db2 | 61 | mipscoff_symfile_init (struct objfile *objfile) |
c906108c SS |
62 | { |
63 | } | |
64 | ||
65 | /* Read a symbol file from a file. */ | |
66 | ||
67 | static void | |
fba45db2 | 68 | mipscoff_symfile_read (struct objfile *objfile, int mainline) |
c906108c SS |
69 | { |
70 | bfd *abfd = objfile->obfd; | |
c5aa993b | 71 | struct cleanup *back_to; |
c906108c SS |
72 | |
73 | init_minimal_symbol_collection (); | |
56e290f4 | 74 | back_to = make_cleanup_discard_minimal_symbols (); |
c906108c SS |
75 | |
76 | /* Now that the executable file is positioned at symbol table, | |
77 | process it and define symbols accordingly. */ | |
78 | ||
79 | if (!((*ecoff_backend (abfd)->debug_swap.read_debug_info) | |
80 | (abfd, (asection *) NULL, &ecoff_data (abfd)->debug_info))) | |
8a3fe4f8 | 81 | error (_("Error reading symbol table: %s"), bfd_errmsg (bfd_get_error ())); |
c906108c SS |
82 | |
83 | mdebug_build_psymtabs (objfile, &ecoff_backend (abfd)->debug_swap, | |
d4f3574e | 84 | &ecoff_data (abfd)->debug_info); |
c906108c SS |
85 | |
86 | /* Add alpha coff dynamic symbols. */ | |
87 | ||
96baa820 | 88 | read_alphacoff_dynamic_symtab (objfile->section_offsets, objfile); |
c906108c SS |
89 | |
90 | /* Install any minimal symbols that have been collected as the current | |
91 | minimal symbols for this objfile. */ | |
92 | ||
93 | install_minimal_symbols (objfile); | |
c906108c SS |
94 | do_cleanups (back_to); |
95 | } | |
96 | ||
97 | /* Perform any local cleanups required when we are done with a | |
98 | particular objfile. */ | |
99 | ||
100 | static void | |
fba45db2 | 101 | mipscoff_symfile_finish (struct objfile *objfile) |
c906108c SS |
102 | { |
103 | } | |
104 | ||
105 | /* Alpha OSF/1 encapsulates the dynamic symbols in ELF format in a | |
303d2914 MK |
106 | standard COFF section. The ELF format for the symbols differs from |
107 | the format defined in elf/external.h. It seems that a normal ELF | |
108 | 32-bit format is used, and the representation only changes because | |
109 | longs are 64-bit on the alpha. In addition, the handling of | |
110 | text/data section indices for symbols is different from the ELF | |
111 | ABI. As the BFD linker currently does not support dynamic linking | |
112 | on the alpha, there seems to be no reason to pollute BFD with | |
113 | another mixture of object file formats for now. */ | |
c906108c SS |
114 | |
115 | /* Format of an alpha external ELF symbol. */ | |
116 | ||
c5aa993b JM |
117 | typedef struct |
118 | { | |
303d2914 MK |
119 | unsigned char st_name[4]; /* Symbol name, index in string table. */ |
120 | unsigned char st_pad[4]; /* Pad to long word boundary. */ | |
121 | unsigned char st_value[8]; /* Value of the symbol. */ | |
122 | unsigned char st_size[4]; /* Associated symbol size. */ | |
123 | unsigned char st_info[1]; /* Type and binding attributes. */ | |
124 | unsigned char st_other[1]; /* No defined meaning, 0. */ | |
125 | unsigned char st_shndx[2]; /* Associated section index. */ | |
126 | } Elfalpha_External_Sym; | |
c906108c SS |
127 | |
128 | /* Format of an alpha external ELF dynamic info structure. */ | |
129 | ||
c5aa993b | 130 | typedef struct |
303d2914 MK |
131 | { |
132 | unsigned char d_tag[4]; /* Tag. */ | |
133 | unsigned char d_pad[4]; /* Pad to long word boundary. */ | |
134 | union | |
c5aa993b | 135 | { |
303d2914 MK |
136 | unsigned char d_ptr[8]; /* Pointer value. */ |
137 | unsigned char d_val[4]; /* Integer value. */ | |
c5aa993b | 138 | } |
303d2914 MK |
139 | d_un; |
140 | } Elfalpha_External_Dyn; | |
c906108c SS |
141 | |
142 | /* Struct to obtain the section pointers for alpha dynamic symbol info. */ | |
143 | ||
c5aa993b | 144 | struct alphacoff_dynsecinfo |
303d2914 MK |
145 | { |
146 | asection *sym_sect; /* Section pointer for .dynsym section. */ | |
147 | asection *str_sect; /* Section pointer for .dynstr section. */ | |
148 | asection *dyninfo_sect; /* Section pointer for .dynamic section. */ | |
149 | asection *got_sect; /* Section pointer for .got section. */ | |
150 | }; | |
c906108c | 151 | |
c906108c | 152 | /* We are called once per section from read_alphacoff_dynamic_symtab. |
303d2914 MK |
153 | We need to examine each section we are passed, check to see if it |
154 | is something we are interested in processing, and if so, stash away | |
155 | some access information for the section. */ | |
c906108c SS |
156 | |
157 | static void | |
12b9c64f | 158 | alphacoff_locate_sections (bfd *ignore_abfd, asection *sectp, void *sip) |
c906108c | 159 | { |
52f0bd74 | 160 | struct alphacoff_dynsecinfo *si; |
c906108c SS |
161 | |
162 | si = (struct alphacoff_dynsecinfo *) sip; | |
163 | ||
303d2914 MK |
164 | if (strcmp (sectp->name, ".dynsym") == 0) |
165 | si->sym_sect = sectp; | |
166 | else if (strcmp (sectp->name, ".dynstr") == 0) | |
167 | si->str_sect = sectp; | |
168 | else if (strcmp (sectp->name, ".dynamic") == 0) | |
169 | si->dyninfo_sect = sectp; | |
170 | else if (strcmp (sectp->name, ".got") == 0) | |
c906108c | 171 | si->got_sect = sectp; |
c906108c SS |
172 | } |
173 | ||
303d2914 MK |
174 | /* Scan an alpha dynamic symbol table for symbols of interest and add |
175 | them to the minimal symbol table. */ | |
c906108c SS |
176 | |
177 | static void | |
fba45db2 KB |
178 | read_alphacoff_dynamic_symtab (struct section_offsets *section_offsets, |
179 | struct objfile *objfile) | |
c906108c SS |
180 | { |
181 | bfd *abfd = objfile->obfd; | |
182 | struct alphacoff_dynsecinfo si; | |
183 | char *sym_secptr; | |
184 | char *str_secptr; | |
185 | char *dyninfo_secptr; | |
186 | char *got_secptr; | |
187 | bfd_size_type sym_secsize; | |
188 | bfd_size_type str_secsize; | |
189 | bfd_size_type dyninfo_secsize; | |
190 | bfd_size_type got_secsize; | |
191 | int sym_count; | |
192 | int i; | |
193 | int stripped; | |
194 | Elfalpha_External_Sym *x_symp; | |
195 | char *dyninfo_p; | |
196 | char *dyninfo_end; | |
197 | int got_entry_size = 8; | |
198 | int dt_mips_local_gotno = -1; | |
199 | int dt_mips_gotsym = -1; | |
4b2e4867 | 200 | struct cleanup *cleanups; |
c906108c | 201 | |
c906108c SS |
202 | /* We currently only know how to handle alpha dynamic symbols. */ |
203 | if (bfd_get_arch (abfd) != bfd_arch_alpha) | |
204 | return; | |
205 | ||
206 | /* Locate the dynamic symbols sections and read them in. */ | |
207 | memset ((char *) &si, 0, sizeof (si)); | |
12b9c64f | 208 | bfd_map_over_sections (abfd, alphacoff_locate_sections, (void *) & si); |
303d2914 MK |
209 | if (si.sym_sect == NULL || si.str_sect == NULL |
210 | || si.dyninfo_sect == NULL || si.got_sect == NULL) | |
c906108c SS |
211 | return; |
212 | ||
2c500098 AM |
213 | sym_secsize = bfd_get_section_size (si.sym_sect); |
214 | str_secsize = bfd_get_section_size (si.str_sect); | |
215 | dyninfo_secsize = bfd_get_section_size (si.dyninfo_sect); | |
216 | got_secsize = bfd_get_section_size (si.got_sect); | |
4b2e4867 PS |
217 | sym_secptr = xmalloc (sym_secsize); |
218 | cleanups = make_cleanup (free, sym_secptr); | |
219 | str_secptr = xmalloc (str_secsize); | |
220 | make_cleanup (free, str_secptr); | |
221 | dyninfo_secptr = xmalloc (dyninfo_secsize); | |
222 | make_cleanup (free, dyninfo_secptr); | |
223 | got_secptr = xmalloc (got_secsize); | |
224 | make_cleanup (free, got_secptr); | |
c906108c SS |
225 | |
226 | if (!bfd_get_section_contents (abfd, si.sym_sect, sym_secptr, | |
c5aa993b | 227 | (file_ptr) 0, sym_secsize)) |
c906108c SS |
228 | return; |
229 | if (!bfd_get_section_contents (abfd, si.str_sect, str_secptr, | |
c5aa993b | 230 | (file_ptr) 0, str_secsize)) |
c906108c SS |
231 | return; |
232 | if (!bfd_get_section_contents (abfd, si.dyninfo_sect, dyninfo_secptr, | |
c5aa993b | 233 | (file_ptr) 0, dyninfo_secsize)) |
c906108c SS |
234 | return; |
235 | if (!bfd_get_section_contents (abfd, si.got_sect, got_secptr, | |
c5aa993b | 236 | (file_ptr) 0, got_secsize)) |
c906108c SS |
237 | return; |
238 | ||
303d2914 MK |
239 | /* Find the number of local GOT entries and the index for the the |
240 | first dynamic symbol in the GOT. */ | |
c906108c SS |
241 | for (dyninfo_p = dyninfo_secptr, dyninfo_end = dyninfo_p + dyninfo_secsize; |
242 | dyninfo_p < dyninfo_end; | |
243 | dyninfo_p += sizeof (Elfalpha_External_Dyn)) | |
244 | { | |
c5aa993b | 245 | Elfalpha_External_Dyn *x_dynp = (Elfalpha_External_Dyn *) dyninfo_p; |
c906108c SS |
246 | long dyn_tag; |
247 | ||
248 | dyn_tag = bfd_h_get_32 (abfd, (bfd_byte *) x_dynp->d_tag); | |
249 | if (dyn_tag == DT_NULL) | |
250 | break; | |
251 | else if (dyn_tag == DT_MIPS_LOCAL_GOTNO) | |
252 | { | |
253 | if (dt_mips_local_gotno < 0) | |
254 | dt_mips_local_gotno | |
255 | = bfd_h_get_32 (abfd, (bfd_byte *) x_dynp->d_un.d_val); | |
256 | } | |
257 | else if (dyn_tag == DT_MIPS_GOTSYM) | |
258 | { | |
259 | if (dt_mips_gotsym < 0) | |
260 | dt_mips_gotsym | |
261 | = bfd_h_get_32 (abfd, (bfd_byte *) x_dynp->d_un.d_val); | |
262 | } | |
263 | } | |
264 | if (dt_mips_local_gotno < 0 || dt_mips_gotsym < 0) | |
265 | return; | |
266 | ||
303d2914 MK |
267 | /* Scan all dynamic symbols and enter them into the minimal symbol |
268 | table if appropriate. */ | |
c906108c SS |
269 | sym_count = sym_secsize / sizeof (Elfalpha_External_Sym); |
270 | stripped = (bfd_get_symcount (abfd) == 0); | |
271 | ||
272 | /* Skip first symbol, which is a null dummy. */ | |
273 | for (i = 1, x_symp = (Elfalpha_External_Sym *) sym_secptr + 1; | |
274 | i < sym_count; | |
275 | i++, x_symp++) | |
276 | { | |
277 | unsigned long strx; | |
278 | char *name; | |
279 | bfd_vma sym_value; | |
280 | unsigned char sym_info; | |
281 | unsigned int sym_shndx; | |
282 | int isglobal; | |
283 | enum minimal_symbol_type ms_type; | |
284 | ||
285 | strx = bfd_h_get_32 (abfd, (bfd_byte *) x_symp->st_name); | |
286 | if (strx >= str_secsize) | |
287 | continue; | |
288 | name = str_secptr + strx; | |
289 | if (*name == '\0' || *name == '.') | |
290 | continue; | |
291 | ||
292 | sym_value = bfd_h_get_64 (abfd, (bfd_byte *) x_symp->st_value); | |
293 | sym_info = bfd_h_get_8 (abfd, (bfd_byte *) x_symp->st_info); | |
294 | sym_shndx = bfd_h_get_16 (abfd, (bfd_byte *) x_symp->st_shndx); | |
295 | isglobal = (ELF_ST_BIND (sym_info) == STB_GLOBAL); | |
296 | ||
297 | if (sym_shndx == SHN_UNDEF) | |
298 | { | |
299 | /* Handle undefined functions which are defined in a shared | |
300 | library. */ | |
301 | if (ELF_ST_TYPE (sym_info) != STT_FUNC | |
302 | || ELF_ST_BIND (sym_info) != STB_GLOBAL) | |
303 | continue; | |
304 | ||
305 | ms_type = mst_solib_trampoline; | |
306 | ||
307 | /* If sym_value is nonzero, it points to the shared library | |
308 | trampoline entry, which is what we are looking for. | |
309 | ||
310 | If sym_value is zero, then we have to get the GOT entry | |
311 | for the symbol. | |
c906108c | 312 | |
303d2914 MK |
313 | If the GOT entry is nonzero, it represents the quickstart |
314 | address of the function and we use that as the symbol | |
315 | value. | |
316 | ||
317 | If the GOT entry is zero, the function address has to be | |
318 | resolved by the runtime loader before the executable is | |
319 | started. We are unable to find any meaningful address | |
320 | for these functions in the executable file, so we skip | |
321 | them. */ | |
c906108c SS |
322 | if (sym_value == 0) |
323 | { | |
324 | int got_entry_offset = | |
303d2914 | 325 | (i - dt_mips_gotsym + dt_mips_local_gotno) * got_entry_size; |
c906108c SS |
326 | |
327 | if (got_entry_offset < 0 || got_entry_offset >= got_secsize) | |
328 | continue; | |
329 | sym_value = | |
330 | bfd_h_get_64 (abfd, | |
331 | (bfd_byte *) (got_secptr + got_entry_offset)); | |
332 | if (sym_value == 0) | |
333 | continue; | |
334 | } | |
335 | } | |
336 | else | |
337 | { | |
303d2914 MK |
338 | /* Symbols defined in the executable itself. We only care |
339 | about them if this is a stripped executable, otherwise | |
340 | they have been retrieved from the normal symbol table | |
341 | already. */ | |
c906108c SS |
342 | if (!stripped) |
343 | continue; | |
344 | ||
345 | if (sym_shndx == SHN_MIPS_TEXT) | |
346 | { | |
347 | if (isglobal) | |
348 | ms_type = mst_text; | |
349 | else | |
350 | ms_type = mst_file_text; | |
b8fbeb18 | 351 | sym_value += ANOFFSET (section_offsets, SECT_OFF_TEXT (objfile)); |
c906108c SS |
352 | } |
353 | else if (sym_shndx == SHN_MIPS_DATA) | |
354 | { | |
355 | if (isglobal) | |
356 | ms_type = mst_data; | |
357 | else | |
358 | ms_type = mst_file_data; | |
b8fbeb18 | 359 | sym_value += ANOFFSET (section_offsets, SECT_OFF_DATA (objfile)); |
c906108c SS |
360 | } |
361 | else if (sym_shndx == SHN_MIPS_ACOMMON) | |
362 | { | |
363 | if (isglobal) | |
364 | ms_type = mst_bss; | |
365 | else | |
366 | ms_type = mst_file_bss; | |
b8fbeb18 | 367 | sym_value += ANOFFSET (section_offsets, SECT_OFF_BSS (objfile)); |
c906108c SS |
368 | } |
369 | else if (sym_shndx == SHN_ABS) | |
370 | { | |
371 | ms_type = mst_abs; | |
372 | } | |
373 | else | |
374 | { | |
375 | continue; | |
376 | } | |
377 | } | |
378 | ||
379 | prim_record_minimal_symbol (name, sym_value, ms_type, objfile); | |
380 | } | |
4b2e4867 PS |
381 | |
382 | do_cleanups (cleanups); | |
c906108c SS |
383 | } |
384 | ||
303d2914 | 385 | /* Initialization. */ |
c906108c SS |
386 | |
387 | static struct sym_fns ecoff_sym_fns = | |
388 | { | |
389 | bfd_target_ecoff_flavour, | |
390 | mipscoff_new_init, /* sym_new_init: init anything gbl to entire symtab */ | |
391 | mipscoff_symfile_init, /* sym_init: read initial info, setup for sym_read() */ | |
392 | mipscoff_symfile_read, /* sym_read: read a symbol file into symtab */ | |
393 | mipscoff_symfile_finish, /* sym_finish: finished with file, cleanup */ | |
394 | default_symfile_offsets, /* sym_offsets: dummy FIXME til implem sym reloc */ | |
31d99776 DJ |
395 | default_symfile_segments, /* sym_segments: Get segment information from |
396 | a file. */ | |
c295b2e5 | 397 | NULL, /* sym_read_linetable */ |
c906108c SS |
398 | NULL /* next: pointer to next struct sym_fns */ |
399 | }; | |
400 | ||
303d2914 MK |
401 | /* Provide a prototype to silence -Wmissing-prototypes. */ |
402 | void _initialize_mipsread (void); | |
403 | ||
c906108c | 404 | void |
fba45db2 | 405 | _initialize_mipsread (void) |
c906108c SS |
406 | { |
407 | add_symtab_fns (&ecoff_sym_fns); | |
408 | } |