1/* Read NLM (NetWare Loadable Module) format executable files for GDB. 2 Copyright 1993, 1994, 1995, 1996, 1998, 1999, 2000 3 Free Software Foundation, Inc. 4 Written by Fred Fish at Cygnus Support (fnf@cygnus.com). 5 6 This file is part of GDB. 7 8 This program is free software; you can redistribute it and/or modify 9 it under the terms of the GNU General Public License as published by 10 the Free Software Foundation; either version 2 of the License, or 11 (at your option) any later version. 12 13 This program is distributed in the hope that it will be useful, 14 but WITHOUT ANY WARRANTY; without even the implied warranty of 15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 GNU General Public License for more details. 17 18 You should have received a copy of the GNU General Public License 19 along with this program; if not, write to the Free Software 20 Foundation, Inc., 59 Temple Place - Suite 330, 21 Boston, MA 02111-1307, USA. */ 22 23#include "defs.h" 24#include "bfd.h" 25#include "symtab.h" 26#include "symfile.h" 27#include "objfiles.h" 28#include "buildsym.h" 29#include "stabsread.h" 30#include "block.h" 31 32extern void _initialize_nlmread (void); 33 34static void nlm_new_init (struct objfile *); 35 36static void nlm_symfile_init (struct objfile *); 37 38static void nlm_symfile_read (struct objfile *, int); 39 40static void nlm_symfile_finish (struct objfile *); 41 42static void nlm_symtab_read (bfd *, CORE_ADDR, struct objfile *); 43 44/* Initialize anything that needs initializing when a completely new symbol 45 file is specified (not just adding some symbols from another file, e.g. a 46 shared library). 47 48 We reinitialize buildsym, since gdb will be able to read stabs from an NLM 49 file at some point in the near future. */ 50 51static void 52nlm_new_init (struct objfile *ignore) 53{ 54 stabsread_new_init (); 55 buildsym_new_init (); 56} 57 58 59/* NLM specific initialization routine for reading symbols. 60 61 It is passed a pointer to a struct sym_fns which contains, among other 62 things, the BFD for the file whose symbols are being read, and a slot for 63 a pointer to "private data" which we can fill with goodies. 64 65 For now at least, we have nothing in particular to do, so this function is 66 just a stub. */ 67 68static void 69nlm_symfile_init (struct objfile *ignore) 70{ 71} 72 73/* 74 75 LOCAL FUNCTION 76 77 nlm_symtab_read -- read the symbol table of an NLM file 78 79 SYNOPSIS 80 81 void nlm_symtab_read (bfd *abfd, CORE_ADDR addr, 82 struct objfile *objfile) 83 84 DESCRIPTION 85 86 Given an open bfd, a base address to relocate symbols to, and a 87 flag that specifies whether or not this bfd is for an executable 88 or not (may be shared library for example), add all the global 89 function and data symbols to the minimal symbol table. 90 */ 91 92static void 93nlm_symtab_read (bfd *abfd, CORE_ADDR addr, struct objfile *objfile) 94{ 95 long storage_needed; 96 asymbol *sym; 97 asymbol **symbol_table; 98 long number_of_symbols; 99 long i; 100 struct cleanup *back_to; 101 CORE_ADDR symaddr; 102 enum minimal_symbol_type ms_type; 103 104 storage_needed = bfd_get_symtab_upper_bound (abfd); 105 if (storage_needed < 0) 106 error ("Can't read symbols from %s: %s", bfd_get_filename (abfd), 107 bfd_errmsg (bfd_get_error ())); 108 if (storage_needed > 0) 109 { 110 symbol_table = (asymbol **) xmalloc (storage_needed); 111 back_to = make_cleanup (xfree, symbol_table); 112 number_of_symbols = bfd_canonicalize_symtab (abfd, symbol_table); 113 if (number_of_symbols < 0) 114 error ("Can't read symbols from %s: %s", bfd_get_filename (abfd), 115 bfd_errmsg (bfd_get_error ())); 116 117 for (i = 0; i < number_of_symbols; i++) 118 { 119 sym = symbol_table[i]; 120 if ( /*sym -> flags & BSF_GLOBAL */ 1) 121 { 122 /* Bfd symbols are section relative. */ 123 symaddr = sym->value + sym->section->vma; 124 /* Relocate all non-absolute symbols by base address. */ 125 if (sym->section != &bfd_abs_section) 126 symaddr += addr; 127 128 /* For non-absolute symbols, use the type of the section 129 they are relative to, to intuit text/data. BFD provides 130 no way of figuring this out for absolute symbols. */ 131 if (sym->section->flags & SEC_CODE) 132 ms_type = mst_text; 133 else if (sym->section->flags & SEC_DATA) 134 ms_type = mst_data; 135 else 136 ms_type = mst_unknown; 137 138 prim_record_minimal_symbol (sym->name, symaddr, ms_type, 139 objfile); 140 } 141 } 142 do_cleanups (back_to); 143 } 144} 145 146 147/* Scan and build partial symbols for a symbol file. 148 We have been initialized by a call to nlm_symfile_init, which 149 currently does nothing. 150 151 SECTION_OFFSETS is a set of offsets to apply to relocate the symbols 152 in each section. We simplify it down to a single offset for all 153 symbols. FIXME. 154 155 MAINLINE is true if we are reading the main symbol 156 table (as opposed to a shared lib or dynamically loaded file). 157 158 This function only does the minimum work necessary for letting the 159 user "name" things symbolically; it does not read the entire symtab. 160 Instead, it reads the external and static symbols and puts them in partial 161 symbol tables. When more extensive information is requested of a 162 file, the corresponding partial symbol table is mutated into a full 163 fledged symbol table by going back and reading the symbols 164 for real. 165 166 Note that NLM files have two sets of information that is potentially 167 useful for building gdb's minimal symbol table. The first is a list 168 of the publically exported symbols, and is currently used to build 169 bfd's canonical symbol table. The second is an optional native debugging 170 format which contains additional symbols (and possibly duplicates of 171 the publically exported symbols). The optional native debugging format 172 is not currently used. */ 173 174static void 175nlm_symfile_read (struct objfile *objfile, int mainline) 176{ 177 bfd *abfd = objfile->obfd; 178 struct cleanup *back_to; 179 CORE_ADDR offset; 180 struct symbol *mainsym; 181 182 init_minimal_symbol_collection (); 183 back_to = make_cleanup_discard_minimal_symbols (); 184 185 /* FIXME, should take a section_offsets param, not just an offset. */ 186 187 offset = ANOFFSET (objfile->section_offsets, 0); 188 189 /* Process the NLM export records, which become the bfd's canonical symbol 190 table. */ 191 192 nlm_symtab_read (abfd, offset, objfile); 193 194 /* Install any minimal symbols that have been collected as the current 195 minimal symbols for this objfile. */ 196 197 install_minimal_symbols (objfile); 198 do_cleanups (back_to); 199 200 stabsect_build_psymtabs (objfile, mainline, ".stab", 201 ".stabstr", ".text"); 202 203 mainsym = lookup_symbol (main_name (), NULL, VAR_DOMAIN, NULL, NULL); 204 205 if (mainsym 206 && SYMBOL_CLASS (mainsym) == LOC_BLOCK) 207 { 208 objfile->ei.main_func_lowpc = BLOCK_START (SYMBOL_BLOCK_VALUE (mainsym)); 209 objfile->ei.main_func_highpc = BLOCK_END (SYMBOL_BLOCK_VALUE (mainsym)); 210 } 211 212 /* FIXME: We could locate and read the optional native debugging format 213 here and add the symbols to the minimal symbol table. */ 214} 215 216 217/* Perform any local cleanups required when we are done with a particular 218 objfile. I.E, we are in the process of discarding all symbol information 219 for an objfile, freeing up all memory held for it, and unlinking the 220 objfile struct from the global list of known objfiles. */ 221 222static void 223nlm_symfile_finish (struct objfile *objfile) 224{ 225 if (objfile->sym_private != NULL) 226 { 227 xmfree (objfile->md, objfile->sym_private); 228 } 229} 230 231/* Register that we are able to handle NLM file format. */ 232 233static struct sym_fns nlm_sym_fns = 234{ 235 bfd_target_nlm_flavour, 236 nlm_new_init, /* sym_new_init: init anything gbl to entire symtab */ 237 nlm_symfile_init, /* sym_init: read initial info, setup for sym_read() */ 238 nlm_symfile_read, /* sym_read: read a symbol file into symtab */ 239 nlm_symfile_finish, /* sym_finish: finished with file, cleanup */ 240 default_symfile_offsets, /* sym_offsets: Translate ext. to int. relocation */ 241 NULL /* next: pointer to next struct sym_fns */ 242}; 243 244void 245_initialize_nlmread (void) 246{ 247 add_symtab_fns (&nlm_sym_fns); 248} 249