1 /* Read a symbol table in MIPS' format (Third-Eye).
2 Copyright 1986, 1987, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996,
3 1998, 1999, 2000, 2001, 2003, 2004
4 Free Software Foundation, Inc.
5 Contributed by Alessandro Forin (af@cs.cmu.edu) at CMU. Major work
6 by Per Bothner, John Gilmore and Ian Lance Taylor at Cygnus Support.
8 This file is part of GDB.
10 This program is free software; you can redistribute it and/or modify
11 it under the terms of the GNU General Public License as published by
12 the Free Software Foundation; either version 2 of the License, or
13 (at your option) any later version.
15 This program is distributed in the hope that it will be useful,
16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 GNU General Public License for more details.
20 You should have received a copy of the GNU General Public License
21 along with this program; if not, write to the Free Software
22 Foundation, Inc., 59 Temple Place - Suite 330,
23 Boston, MA 02111-1307, USA. */
25 /* Read symbols from an ECOFF file. Most of the work is done in
29 #include "gdb_string.h"
34 #include "stabsread.h"
37 #include "coff/internal.h"
38 #include "coff/ecoff.h"
39 #include "libcoff.h" /* Private BFD COFF information. */
40 #include "libecoff.h" /* Private BFD ECOFF information. */
41 #include "elf/common.h"
44 extern void _initialize_mipsread (void);
46 static void mipscoff_new_init (struct objfile
*);
48 static void mipscoff_symfile_init (struct objfile
*);
50 static void mipscoff_symfile_read (struct objfile
*, int);
52 static void mipscoff_symfile_finish (struct objfile
*);
55 read_alphacoff_dynamic_symtab (struct section_offsets
*,
56 struct objfile
*objfile
);
58 /* Initialize anything that needs initializing when a completely new
59 symbol file is specified (not just adding some symbols from another
60 file, e.g. a shared library). */
63 mipscoff_new_init (struct objfile
*ignore
)
65 stabsread_new_init ();
69 /* Initialize to read a symbol file (nothing to do). */
72 mipscoff_symfile_init (struct objfile
*objfile
)
76 /* Read a symbol file from a file. */
79 mipscoff_symfile_read (struct objfile
*objfile
, int mainline
)
81 bfd
*abfd
= objfile
->obfd
;
82 struct cleanup
*back_to
;
84 init_minimal_symbol_collection ();
85 back_to
= make_cleanup_discard_minimal_symbols ();
87 /* Now that the executable file is positioned at symbol table,
88 process it and define symbols accordingly. */
90 if (!((*ecoff_backend (abfd
)->debug_swap
.read_debug_info
)
91 (abfd
, (asection
*) NULL
, &ecoff_data (abfd
)->debug_info
)))
92 error ("Error reading symbol table: %s", bfd_errmsg (bfd_get_error ()));
94 mdebug_build_psymtabs (objfile
, &ecoff_backend (abfd
)->debug_swap
,
95 &ecoff_data (abfd
)->debug_info
);
97 /* Add alpha coff dynamic symbols. */
99 read_alphacoff_dynamic_symtab (objfile
->section_offsets
, objfile
);
101 /* Install any minimal symbols that have been collected as the current
102 minimal symbols for this objfile. */
104 install_minimal_symbols (objfile
);
106 /* If the entry_file bounds are still unknown after processing the
107 partial symbols, then try to set them from the minimal symbols
108 surrounding the entry_point. */
111 && objfile
->ei
.entry_point
!= INVALID_ENTRY_POINT
112 && objfile
->ei
.deprecated_entry_file_lowpc
== INVALID_ENTRY_LOWPC
)
114 struct minimal_symbol
*m
;
116 m
= lookup_minimal_symbol_by_pc (objfile
->ei
.entry_point
);
117 if (m
&& DEPRECATED_SYMBOL_NAME (m
+ 1))
119 objfile
->ei
.deprecated_entry_file_lowpc
= SYMBOL_VALUE_ADDRESS (m
);
120 objfile
->ei
.deprecated_entry_file_highpc
= SYMBOL_VALUE_ADDRESS (m
+ 1);
124 do_cleanups (back_to
);
127 /* Perform any local cleanups required when we are done with a
128 particular objfile. */
131 mipscoff_symfile_finish (struct objfile
*objfile
)
135 /* Alpha OSF/1 encapsulates the dynamic symbols in ELF format in a
136 standard coff section. The ELF format for the symbols differs from
137 the format defined in elf/external.h. It seems that a normal ELF 32 bit
138 format is used, and the representation only changes because longs are
139 64 bit on the alpha. In addition, the handling of text/data section
140 indices for symbols is different from the ELF ABI.
141 As the BFD linker currently does not support dynamic linking on the alpha,
142 there seems to be no reason to pollute BFD with another mixture of object
143 file formats for now. */
145 /* Format of an alpha external ELF symbol. */
149 unsigned char st_name
[4]; /* Symbol name, index in string tbl */
150 unsigned char st_pad
[4]; /* Pad to long word boundary */
151 unsigned char st_value
[8]; /* Value of the symbol */
152 unsigned char st_size
[4]; /* Associated symbol size */
153 unsigned char st_info
[1]; /* Type and binding attributes */
154 unsigned char st_other
[1]; /* No defined meaning, 0 */
155 unsigned char st_shndx
[2]; /* Associated section index */
157 Elfalpha_External_Sym
;
159 /* Format of an alpha external ELF dynamic info structure. */
163 unsigned char d_tag
[4]; /* Tag */
164 unsigned char d_pad
[4]; /* Pad to long word boundary */
167 unsigned char d_ptr
[8]; /* Pointer value */
168 unsigned char d_val
[4]; /* Integer value */
172 Elfalpha_External_Dyn
;
174 /* Struct to obtain the section pointers for alpha dynamic symbol info. */
176 struct alphacoff_dynsecinfo
178 asection
*sym_sect
; /* Section pointer for .dynsym section */
179 asection
*str_sect
; /* Section pointer for .dynstr section */
180 asection
*dyninfo_sect
; /* Section pointer for .dynamic section */
181 asection
*got_sect
; /* Section pointer for .got section */
184 /* We are called once per section from read_alphacoff_dynamic_symtab.
185 We need to examine each section we are passed, check to see
186 if it is something we are interested in processing, and
187 if so, stash away some access information for the section. */
190 alphacoff_locate_sections (bfd
*ignore_abfd
, asection
*sectp
, void *sip
)
192 struct alphacoff_dynsecinfo
*si
;
194 si
= (struct alphacoff_dynsecinfo
*) sip
;
196 if (DEPRECATED_STREQ (sectp
->name
, ".dynsym"))
198 si
->sym_sect
= sectp
;
200 else if (DEPRECATED_STREQ (sectp
->name
, ".dynstr"))
202 si
->str_sect
= sectp
;
204 else if (DEPRECATED_STREQ (sectp
->name
, ".dynamic"))
206 si
->dyninfo_sect
= sectp
;
208 else if (DEPRECATED_STREQ (sectp
->name
, ".got"))
210 si
->got_sect
= sectp
;
214 /* Scan an alpha dynamic symbol table for symbols of interest and
215 add them to the minimal symbol table. */
218 read_alphacoff_dynamic_symtab (struct section_offsets
*section_offsets
,
219 struct objfile
*objfile
)
221 bfd
*abfd
= objfile
->obfd
;
222 struct alphacoff_dynsecinfo si
;
225 char *dyninfo_secptr
;
227 bfd_size_type sym_secsize
;
228 bfd_size_type str_secsize
;
229 bfd_size_type dyninfo_secsize
;
230 bfd_size_type got_secsize
;
234 Elfalpha_External_Sym
*x_symp
;
237 int got_entry_size
= 8;
238 int dt_mips_local_gotno
= -1;
239 int dt_mips_gotsym
= -1;
240 struct cleanup
*cleanups
;
243 /* We currently only know how to handle alpha dynamic symbols. */
244 if (bfd_get_arch (abfd
) != bfd_arch_alpha
)
247 /* Locate the dynamic symbols sections and read them in. */
248 memset ((char *) &si
, 0, sizeof (si
));
249 bfd_map_over_sections (abfd
, alphacoff_locate_sections
, (void *) & si
);
250 if (si
.sym_sect
== NULL
251 || si
.str_sect
== NULL
252 || si
.dyninfo_sect
== NULL
253 || si
.got_sect
== NULL
)
256 sym_secsize
= bfd_get_section_size_before_reloc (si
.sym_sect
);
257 str_secsize
= bfd_get_section_size_before_reloc (si
.str_sect
);
258 dyninfo_secsize
= bfd_get_section_size_before_reloc (si
.dyninfo_sect
);
259 got_secsize
= bfd_get_section_size_before_reloc (si
.got_sect
);
260 sym_secptr
= xmalloc (sym_secsize
);
261 cleanups
= make_cleanup (free
, sym_secptr
);
262 str_secptr
= xmalloc (str_secsize
);
263 make_cleanup (free
, str_secptr
);
264 dyninfo_secptr
= xmalloc (dyninfo_secsize
);
265 make_cleanup (free
, dyninfo_secptr
);
266 got_secptr
= xmalloc (got_secsize
);
267 make_cleanup (free
, got_secptr
);
269 if (!bfd_get_section_contents (abfd
, si
.sym_sect
, sym_secptr
,
270 (file_ptr
) 0, sym_secsize
))
272 if (!bfd_get_section_contents (abfd
, si
.str_sect
, str_secptr
,
273 (file_ptr
) 0, str_secsize
))
275 if (!bfd_get_section_contents (abfd
, si
.dyninfo_sect
, dyninfo_secptr
,
276 (file_ptr
) 0, dyninfo_secsize
))
278 if (!bfd_get_section_contents (abfd
, si
.got_sect
, got_secptr
,
279 (file_ptr
) 0, got_secsize
))
282 /* Find the number of local GOT entries and the index for the
283 the first dynamic symbol in the GOT. */
284 for (dyninfo_p
= dyninfo_secptr
, dyninfo_end
= dyninfo_p
+ dyninfo_secsize
;
285 dyninfo_p
< dyninfo_end
;
286 dyninfo_p
+= sizeof (Elfalpha_External_Dyn
))
288 Elfalpha_External_Dyn
*x_dynp
= (Elfalpha_External_Dyn
*) dyninfo_p
;
291 dyn_tag
= bfd_h_get_32 (abfd
, (bfd_byte
*) x_dynp
->d_tag
);
292 if (dyn_tag
== DT_NULL
)
294 else if (dyn_tag
== DT_MIPS_LOCAL_GOTNO
)
296 if (dt_mips_local_gotno
< 0)
298 = bfd_h_get_32 (abfd
, (bfd_byte
*) x_dynp
->d_un
.d_val
);
300 else if (dyn_tag
== DT_MIPS_GOTSYM
)
302 if (dt_mips_gotsym
< 0)
304 = bfd_h_get_32 (abfd
, (bfd_byte
*) x_dynp
->d_un
.d_val
);
307 if (dt_mips_local_gotno
< 0 || dt_mips_gotsym
< 0)
310 /* Scan all dynamic symbols and enter them into the minimal symbol table
312 sym_count
= sym_secsize
/ sizeof (Elfalpha_External_Sym
);
313 stripped
= (bfd_get_symcount (abfd
) == 0);
315 /* Skip first symbol, which is a null dummy. */
316 for (i
= 1, x_symp
= (Elfalpha_External_Sym
*) sym_secptr
+ 1;
323 unsigned char sym_info
;
324 unsigned int sym_shndx
;
326 enum minimal_symbol_type ms_type
;
328 strx
= bfd_h_get_32 (abfd
, (bfd_byte
*) x_symp
->st_name
);
329 if (strx
>= str_secsize
)
331 name
= str_secptr
+ strx
;
332 if (*name
== '\0' || *name
== '.')
335 sym_value
= bfd_h_get_64 (abfd
, (bfd_byte
*) x_symp
->st_value
);
336 sym_info
= bfd_h_get_8 (abfd
, (bfd_byte
*) x_symp
->st_info
);
337 sym_shndx
= bfd_h_get_16 (abfd
, (bfd_byte
*) x_symp
->st_shndx
);
338 isglobal
= (ELF_ST_BIND (sym_info
) == STB_GLOBAL
);
340 if (sym_shndx
== SHN_UNDEF
)
342 /* Handle undefined functions which are defined in a shared
344 if (ELF_ST_TYPE (sym_info
) != STT_FUNC
345 || ELF_ST_BIND (sym_info
) != STB_GLOBAL
)
348 ms_type
= mst_solib_trampoline
;
350 /* If sym_value is nonzero, it points to the shared library
351 trampoline entry, which is what we are looking for.
353 If sym_value is zero, then we have to get the GOT entry
355 If the GOT entry is nonzero, it represents the quickstart
356 address of the function and we use that as the symbol value.
358 If the GOT entry is zero, the function address has to be resolved
359 by the runtime loader before the executable is started.
360 We are unable to find any meaningful address for these
361 functions in the executable file, so we skip them. */
364 int got_entry_offset
=
365 (i
- dt_mips_gotsym
+ dt_mips_local_gotno
) * got_entry_size
;
367 if (got_entry_offset
< 0 || got_entry_offset
>= got_secsize
)
371 (bfd_byte
*) (got_secptr
+ got_entry_offset
));
378 /* Symbols defined in the executable itself. We only care about
379 them if this is a stripped executable, otherwise they have
380 been retrieved from the normal symbol table already. */
384 if (sym_shndx
== SHN_MIPS_TEXT
)
389 ms_type
= mst_file_text
;
390 sym_value
+= ANOFFSET (section_offsets
, SECT_OFF_TEXT (objfile
));
392 else if (sym_shndx
== SHN_MIPS_DATA
)
397 ms_type
= mst_file_data
;
398 sym_value
+= ANOFFSET (section_offsets
, SECT_OFF_DATA (objfile
));
400 else if (sym_shndx
== SHN_MIPS_ACOMMON
)
405 ms_type
= mst_file_bss
;
406 sym_value
+= ANOFFSET (section_offsets
, SECT_OFF_BSS (objfile
));
408 else if (sym_shndx
== SHN_ABS
)
418 prim_record_minimal_symbol (name
, sym_value
, ms_type
, objfile
);
421 do_cleanups (cleanups
);
426 static struct sym_fns ecoff_sym_fns
=
428 bfd_target_ecoff_flavour
,
429 mipscoff_new_init
, /* sym_new_init: init anything gbl to entire symtab */
430 mipscoff_symfile_init
, /* sym_init: read initial info, setup for sym_read() */
431 mipscoff_symfile_read
, /* sym_read: read a symbol file into symtab */
432 mipscoff_symfile_finish
, /* sym_finish: finished with file, cleanup */
433 default_symfile_offsets
, /* sym_offsets: dummy FIXME til implem sym reloc */
434 NULL
/* next: pointer to next struct sym_fns */
438 _initialize_mipsread (void)
440 add_symtab_fns (&ecoff_sym_fns
);