| 1 | /* Target-dependent code for GNU/Linux, architecture independent. |
| 2 | |
| 3 | Copyright (C) 2009 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 "gdbcore.h" |
| 22 | #include "gdbtypes.h" |
| 23 | #include "linux-tdep.h" |
| 24 | #include "observer.h" |
| 25 | #include "auxv.h" |
| 26 | #include "target.h" |
| 27 | #include "elf-bfd.h" |
| 28 | #include "elf/common.h" |
| 29 | |
| 30 | /* This function is suitable for architectures that don't |
| 31 | extend/override the standard siginfo structure. */ |
| 32 | |
| 33 | struct type * |
| 34 | linux_get_siginfo_type (struct gdbarch *gdbarch) |
| 35 | { |
| 36 | struct type *int_type, *uint_type, *long_type, *void_ptr_type; |
| 37 | struct type *uid_type, *pid_type; |
| 38 | struct type *sigval_type, *clock_type; |
| 39 | struct type *siginfo_type, *sifields_type; |
| 40 | struct type *type; |
| 41 | |
| 42 | int_type = arch_integer_type (gdbarch, gdbarch_int_bit (gdbarch), |
| 43 | 0, "int"); |
| 44 | uint_type = arch_integer_type (gdbarch, gdbarch_int_bit (gdbarch), |
| 45 | 1, "unsigned int"); |
| 46 | long_type = arch_integer_type (gdbarch, gdbarch_long_bit (gdbarch), |
| 47 | 0, "long"); |
| 48 | void_ptr_type = lookup_pointer_type (builtin_type (gdbarch)->builtin_void); |
| 49 | |
| 50 | /* sival_t */ |
| 51 | sigval_type = arch_composite_type (gdbarch, NULL, TYPE_CODE_UNION); |
| 52 | TYPE_NAME (sigval_type) = xstrdup ("sigval_t"); |
| 53 | append_composite_type_field (sigval_type, "sival_int", int_type); |
| 54 | append_composite_type_field (sigval_type, "sival_ptr", void_ptr_type); |
| 55 | |
| 56 | /* __pid_t */ |
| 57 | pid_type = arch_type (gdbarch, TYPE_CODE_TYPEDEF, TYPE_LENGTH (int_type), |
| 58 | xstrdup ("__pid_t")); |
| 59 | TYPE_TARGET_TYPE (pid_type) = int_type; |
| 60 | TYPE_TARGET_STUB (pid_type) = 1; |
| 61 | |
| 62 | /* __uid_t */ |
| 63 | uid_type = arch_type (gdbarch, TYPE_CODE_TYPEDEF, TYPE_LENGTH (uint_type), |
| 64 | xstrdup ("__uid_t")); |
| 65 | TYPE_TARGET_TYPE (uid_type) = uint_type; |
| 66 | TYPE_TARGET_STUB (uid_type) = 1; |
| 67 | |
| 68 | /* __clock_t */ |
| 69 | clock_type = arch_type (gdbarch, TYPE_CODE_TYPEDEF, TYPE_LENGTH (long_type), |
| 70 | xstrdup ("__clock_t")); |
| 71 | TYPE_TARGET_TYPE (clock_type) = long_type; |
| 72 | TYPE_TARGET_STUB (clock_type) = 1; |
| 73 | |
| 74 | /* _sifields */ |
| 75 | sifields_type = arch_composite_type (gdbarch, NULL, TYPE_CODE_UNION); |
| 76 | |
| 77 | { |
| 78 | const int si_max_size = 128; |
| 79 | int si_pad_size; |
| 80 | int size_of_int = gdbarch_int_bit (gdbarch) / HOST_CHAR_BIT; |
| 81 | |
| 82 | /* _pad */ |
| 83 | if (gdbarch_ptr_bit (gdbarch) == 64) |
| 84 | si_pad_size = (si_max_size / size_of_int) - 4; |
| 85 | else |
| 86 | si_pad_size = (si_max_size / size_of_int) - 3; |
| 87 | append_composite_type_field (sifields_type, "_pad", |
| 88 | init_vector_type (int_type, si_pad_size)); |
| 89 | } |
| 90 | |
| 91 | /* _kill */ |
| 92 | type = arch_composite_type (gdbarch, NULL, TYPE_CODE_STRUCT); |
| 93 | append_composite_type_field (type, "si_pid", pid_type); |
| 94 | append_composite_type_field (type, "si_uid", uid_type); |
| 95 | append_composite_type_field (sifields_type, "_kill", type); |
| 96 | |
| 97 | /* _timer */ |
| 98 | type = arch_composite_type (gdbarch, NULL, TYPE_CODE_STRUCT); |
| 99 | append_composite_type_field (type, "si_tid", int_type); |
| 100 | append_composite_type_field (type, "si_overrun", int_type); |
| 101 | append_composite_type_field (type, "si_sigval", sigval_type); |
| 102 | append_composite_type_field (sifields_type, "_timer", type); |
| 103 | |
| 104 | /* _rt */ |
| 105 | type = arch_composite_type (gdbarch, NULL, TYPE_CODE_STRUCT); |
| 106 | append_composite_type_field (type, "si_pid", pid_type); |
| 107 | append_composite_type_field (type, "si_uid", uid_type); |
| 108 | append_composite_type_field (type, "si_sigval", sigval_type); |
| 109 | append_composite_type_field (sifields_type, "_rt", type); |
| 110 | |
| 111 | /* _sigchld */ |
| 112 | type = arch_composite_type (gdbarch, NULL, TYPE_CODE_STRUCT); |
| 113 | append_composite_type_field (type, "si_pid", pid_type); |
| 114 | append_composite_type_field (type, "si_uid", uid_type); |
| 115 | append_composite_type_field (type, "si_status", int_type); |
| 116 | append_composite_type_field (type, "si_utime", clock_type); |
| 117 | append_composite_type_field (type, "si_stime", clock_type); |
| 118 | append_composite_type_field (sifields_type, "_sigchld", type); |
| 119 | |
| 120 | /* _sigfault */ |
| 121 | type = arch_composite_type (gdbarch, NULL, TYPE_CODE_STRUCT); |
| 122 | append_composite_type_field (type, "si_addr", void_ptr_type); |
| 123 | append_composite_type_field (sifields_type, "_sigfault", type); |
| 124 | |
| 125 | /* _sigpoll */ |
| 126 | type = arch_composite_type (gdbarch, NULL, TYPE_CODE_STRUCT); |
| 127 | append_composite_type_field (type, "si_band", long_type); |
| 128 | append_composite_type_field (type, "si_fd", int_type); |
| 129 | append_composite_type_field (sifields_type, "_sigpoll", type); |
| 130 | |
| 131 | /* struct siginfo */ |
| 132 | siginfo_type = arch_composite_type (gdbarch, NULL, TYPE_CODE_STRUCT); |
| 133 | TYPE_NAME (siginfo_type) = xstrdup ("siginfo"); |
| 134 | append_composite_type_field (siginfo_type, "si_signo", int_type); |
| 135 | append_composite_type_field (siginfo_type, "si_errno", int_type); |
| 136 | append_composite_type_field (siginfo_type, "si_code", int_type); |
| 137 | append_composite_type_field_aligned (siginfo_type, |
| 138 | "_sifields", sifields_type, |
| 139 | TYPE_LENGTH (long_type)); |
| 140 | |
| 141 | return siginfo_type; |
| 142 | } |
| 143 | |
| 144 | int |
| 145 | linux_has_shared_address_space (void) |
| 146 | { |
| 147 | /* Determine whether we are running on uClinux or normal Linux |
| 148 | kernel. */ |
| 149 | CORE_ADDR dummy; |
| 150 | int target_is_uclinux; |
| 151 | |
| 152 | target_is_uclinux |
| 153 | = (target_auxv_search (¤t_target, AT_NULL, &dummy) > 0 |
| 154 | && target_auxv_search (¤t_target, AT_PAGESZ, &dummy) == 0); |
| 155 | |
| 156 | return target_is_uclinux; |
| 157 | } |
| 158 | |
| 159 | /* Observer for the executable_changed event, to check whether the new |
| 160 | exec binary is a PIE (Position Independent Executable) specimen, which |
| 161 | is currently unsupported. */ |
| 162 | |
| 163 | static void |
| 164 | check_is_pie_binary (void) |
| 165 | { |
| 166 | Elf_Internal_Ehdr *elf_hdr; |
| 167 | |
| 168 | if (!exec_bfd) |
| 169 | return; |
| 170 | else if (bfd_get_flavour (exec_bfd) != bfd_target_elf_flavour) |
| 171 | return; |
| 172 | |
| 173 | if (elf_tdata (exec_bfd)->elf_header->e_type == ET_DYN) |
| 174 | warning (_("\ |
| 175 | The current binary is a PIE (Position Independent Executable), which\n\ |
| 176 | GDB does NOT currently support. Most debugger features will fail if used\n\ |
| 177 | in this session.\n")); |
| 178 | } |
| 179 | |
| 180 | /* Provide a prototype to silence -Wmissing-prototypes. */ |
| 181 | extern initialize_file_ftype _initialize_linux_tdep; |
| 182 | |
| 183 | void |
| 184 | _initialize_linux_tdep (void) |
| 185 | { |
| 186 | observer_attach_executable_changed (check_is_pie_binary); |
| 187 | } |