| 1 | /* Target-dependent code for DICOS running on i386's, for GDB. |
| 2 | |
| 3 | Copyright (C) 2008 Free Software Foundation, Inc. |
| 4 | |
| 5 | This file is part of GDB. |
| 6 | |
| 7 | This program is free software; you can redistribute it and/or modify |
| 8 | it under the terms of the GNU General Public License as published by |
| 9 | the Free Software Foundation; either version 3 of the License, or |
| 10 | (at your option) any later version. |
| 11 | |
| 12 | This program is distributed in the hope that it will be useful, |
| 13 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 15 | GNU General Public License for more details. |
| 16 | |
| 17 | You should have received a copy of the GNU General Public License |
| 18 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
| 19 | |
| 20 | #include "defs.h" |
| 21 | #include "osabi.h" |
| 22 | #include "gdb_string.h" |
| 23 | #include "solib.h" |
| 24 | #include "solib-target.h" |
| 25 | #include "inferior.h" |
| 26 | |
| 27 | static CORE_ADDR |
| 28 | i386_dicos_push_dummy_code (struct gdbarch *gdbarch, |
| 29 | CORE_ADDR sp, CORE_ADDR funaddr, |
| 30 | struct value **args, int nargs, |
| 31 | struct type *value_type, |
| 32 | CORE_ADDR *real_pc, CORE_ADDR *bp_addr, |
| 33 | struct regcache *regcache) |
| 34 | { |
| 35 | int bplen; |
| 36 | CORE_ADDR bppc = sp; |
| 37 | |
| 38 | gdbarch_breakpoint_from_pc (gdbarch, &bppc, &bplen); |
| 39 | *bp_addr = sp - bplen; |
| 40 | *real_pc = funaddr; |
| 41 | |
| 42 | return *bp_addr; |
| 43 | } |
| 44 | |
| 45 | static void |
| 46 | i386_dicos_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) |
| 47 | { |
| 48 | struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); |
| 49 | |
| 50 | set_solib_ops (gdbarch, &solib_target_so_ops); |
| 51 | |
| 52 | /* There's no (standard definition of) entry point or a guaranteed |
| 53 | text location we could find with a symbol where to place the call |
| 54 | dummy, so we put it on the stack. */ |
| 55 | set_gdbarch_call_dummy_location (gdbarch, ON_STACK); |
| 56 | set_gdbarch_push_dummy_code (gdbarch, i386_dicos_push_dummy_code); |
| 57 | } |
| 58 | |
| 59 | /* Look in the elf symbol table of ABFD for a symbol named WANTED. |
| 60 | Return true if found. */ |
| 61 | static int |
| 62 | i386_dicos_bfd_has_symbol_p (bfd *abfd, const char *wanted) |
| 63 | { |
| 64 | long storage_needed; |
| 65 | int ret = 0; |
| 66 | asymbol **symbol_table = NULL; |
| 67 | |
| 68 | storage_needed = bfd_get_symtab_upper_bound (abfd); |
| 69 | if (storage_needed < 0) |
| 70 | { |
| 71 | warning (_("Can't read elf symbols from %s: %s"), bfd_get_filename (abfd), |
| 72 | bfd_errmsg (bfd_get_error ())); |
| 73 | return 0; |
| 74 | } |
| 75 | |
| 76 | if (storage_needed > 0) |
| 77 | { |
| 78 | long i, symcount; |
| 79 | |
| 80 | symbol_table = xmalloc (storage_needed); |
| 81 | symcount = bfd_canonicalize_symtab (abfd, symbol_table); |
| 82 | |
| 83 | if (symcount < 0) |
| 84 | warning (_("Can't read elf symbols from %s: %s"), |
| 85 | bfd_get_filename (abfd), |
| 86 | bfd_errmsg (bfd_get_error ())); |
| 87 | else |
| 88 | { |
| 89 | for (i = 0; i < symcount; i++) |
| 90 | { |
| 91 | asymbol *sym = symbol_table[i]; |
| 92 | if (sym->name != NULL |
| 93 | && wanted[0] == sym->name[0] |
| 94 | && strcmp (wanted + 1, sym->name + 1) == 0) |
| 95 | { |
| 96 | ret = 1; |
| 97 | break; |
| 98 | } |
| 99 | } |
| 100 | } |
| 101 | } |
| 102 | |
| 103 | xfree (symbol_table); |
| 104 | return ret; |
| 105 | } |
| 106 | |
| 107 | static enum gdb_osabi |
| 108 | i386_dicos_osabi_sniffer (bfd *abfd) |
| 109 | { |
| 110 | char *target_name = bfd_get_target (abfd); |
| 111 | |
| 112 | /* DICOS debug info files don't have a .note.ABI-tag marker or |
| 113 | something similar. We do know there's always a "header" section |
| 114 | of 36 bytes, and there's always a "Dicos_loadModuleInfo" symbol |
| 115 | defined. Look for the section first, as that should be |
| 116 | cheaper. */ |
| 117 | if (strcmp (target_name, "elf32-i386") == 0) |
| 118 | { |
| 119 | asection *section = bfd_get_section_by_name (abfd, "header"); |
| 120 | if (section |
| 121 | && bfd_section_size (abfd, section) == 36 |
| 122 | && i386_dicos_bfd_has_symbol_p (abfd, "Dicos_loadModuleInfo")) |
| 123 | return GDB_OSABI_DICOS; |
| 124 | } |
| 125 | |
| 126 | return GDB_OSABI_UNKNOWN; |
| 127 | } |
| 128 | |
| 129 | /* Provide a prototype to silence -Wmissing-prototypes. */ |
| 130 | void _initialize_i386_dicos_tdep (void); |
| 131 | |
| 132 | void |
| 133 | _initialize_i386_dicos_tdep (void) |
| 134 | { |
| 135 | gdbarch_register_osabi_sniffer (bfd_arch_i386, bfd_target_elf_flavour, |
| 136 | i386_dicos_osabi_sniffer); |
| 137 | |
| 138 | gdbarch_register_osabi (bfd_arch_i386, 0, GDB_OSABI_DICOS, |
| 139 | i386_dicos_init_abi); |
| 140 | } |