| 1 | /* Target-dependent code for FreeBSD, architecture-independent. |
| 2 | |
| 3 | Copyright (C) 2002-2016 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 "auxv.h" |
| 22 | #include "gdbcore.h" |
| 23 | #include "inferior.h" |
| 24 | #include "regcache.h" |
| 25 | #include "regset.h" |
| 26 | #include "gdbthread.h" |
| 27 | #include "xml-syscall.h" |
| 28 | |
| 29 | #include "elf-bfd.h" |
| 30 | #include "fbsd-tdep.h" |
| 31 | |
| 32 | |
| 33 | /* This is how we want PTIDs from core files to be printed. */ |
| 34 | |
| 35 | static char * |
| 36 | fbsd_core_pid_to_str (struct gdbarch *gdbarch, ptid_t ptid) |
| 37 | { |
| 38 | static char buf[80]; |
| 39 | |
| 40 | if (ptid_get_lwp (ptid) != 0) |
| 41 | { |
| 42 | xsnprintf (buf, sizeof buf, "LWP %ld", ptid_get_lwp (ptid)); |
| 43 | return buf; |
| 44 | } |
| 45 | |
| 46 | return normal_pid_to_str (ptid); |
| 47 | } |
| 48 | |
| 49 | /* Extract the name assigned to a thread from a core. Returns the |
| 50 | string in a static buffer. */ |
| 51 | |
| 52 | static const char * |
| 53 | fbsd_core_thread_name (struct gdbarch *gdbarch, struct thread_info *thr) |
| 54 | { |
| 55 | static char buf[80]; |
| 56 | struct bfd_section *section; |
| 57 | bfd_size_type size; |
| 58 | char sectionstr[32]; |
| 59 | |
| 60 | if (ptid_get_lwp (thr->ptid) != 0) |
| 61 | { |
| 62 | /* FreeBSD includes a NT_FREEBSD_THRMISC note for each thread |
| 63 | whose contents are defined by a "struct thrmisc" declared in |
| 64 | <sys/procfs.h> on FreeBSD. The per-thread name is stored as |
| 65 | a null-terminated string as the first member of the |
| 66 | structure. Rather than define the full structure here, just |
| 67 | extract the null-terminated name from the start of the |
| 68 | note. */ |
| 69 | xsnprintf (sectionstr, sizeof sectionstr, ".thrmisc/%ld", |
| 70 | ptid_get_lwp (thr->ptid)); |
| 71 | section = bfd_get_section_by_name (core_bfd, sectionstr); |
| 72 | if (section != NULL && bfd_section_size (core_bfd, section) > 0) |
| 73 | { |
| 74 | /* Truncate the name if it is longer than "buf". */ |
| 75 | size = bfd_section_size (core_bfd, section); |
| 76 | if (size > sizeof buf - 1) |
| 77 | size = sizeof buf - 1; |
| 78 | if (bfd_get_section_contents (core_bfd, section, buf, (file_ptr) 0, |
| 79 | size) |
| 80 | && buf[0] != '\0') |
| 81 | { |
| 82 | buf[size] = '\0'; |
| 83 | |
| 84 | /* Note that each thread will report the process command |
| 85 | as its thread name instead of an empty name if a name |
| 86 | has not been set explicitly. Return a NULL name in |
| 87 | that case. */ |
| 88 | if (strcmp (buf, elf_tdata (core_bfd)->core->program) != 0) |
| 89 | return buf; |
| 90 | } |
| 91 | } |
| 92 | } |
| 93 | |
| 94 | return NULL; |
| 95 | } |
| 96 | |
| 97 | static int |
| 98 | find_signalled_thread (struct thread_info *info, void *data) |
| 99 | { |
| 100 | if (info->suspend.stop_signal != GDB_SIGNAL_0 |
| 101 | && ptid_get_pid (info->ptid) == ptid_get_pid (inferior_ptid)) |
| 102 | return 1; |
| 103 | |
| 104 | return 0; |
| 105 | } |
| 106 | |
| 107 | /* Structure for passing information from |
| 108 | fbsd_collect_thread_registers via an iterator to |
| 109 | fbsd_collect_regset_section_cb. */ |
| 110 | |
| 111 | struct fbsd_collect_regset_section_cb_data |
| 112 | { |
| 113 | const struct regcache *regcache; |
| 114 | bfd *obfd; |
| 115 | char *note_data; |
| 116 | int *note_size; |
| 117 | unsigned long lwp; |
| 118 | enum gdb_signal stop_signal; |
| 119 | int abort_iteration; |
| 120 | }; |
| 121 | |
| 122 | static void |
| 123 | fbsd_collect_regset_section_cb (const char *sect_name, int size, |
| 124 | const struct regset *regset, |
| 125 | const char *human_name, void *cb_data) |
| 126 | { |
| 127 | char *buf; |
| 128 | struct fbsd_collect_regset_section_cb_data *data |
| 129 | = (struct fbsd_collect_regset_section_cb_data *) cb_data; |
| 130 | |
| 131 | if (data->abort_iteration) |
| 132 | return; |
| 133 | |
| 134 | gdb_assert (regset->collect_regset); |
| 135 | |
| 136 | buf = (char *) xmalloc (size); |
| 137 | regset->collect_regset (regset, data->regcache, -1, buf, size); |
| 138 | |
| 139 | /* PRSTATUS still needs to be treated specially. */ |
| 140 | if (strcmp (sect_name, ".reg") == 0) |
| 141 | data->note_data = (char *) elfcore_write_prstatus |
| 142 | (data->obfd, data->note_data, data->note_size, data->lwp, |
| 143 | gdb_signal_to_host (data->stop_signal), buf); |
| 144 | else |
| 145 | data->note_data = (char *) elfcore_write_register_note |
| 146 | (data->obfd, data->note_data, data->note_size, |
| 147 | sect_name, buf, size); |
| 148 | xfree (buf); |
| 149 | |
| 150 | if (data->note_data == NULL) |
| 151 | data->abort_iteration = 1; |
| 152 | } |
| 153 | |
| 154 | /* Records the thread's register state for the corefile note |
| 155 | section. */ |
| 156 | |
| 157 | static char * |
| 158 | fbsd_collect_thread_registers (const struct regcache *regcache, |
| 159 | ptid_t ptid, bfd *obfd, |
| 160 | char *note_data, int *note_size, |
| 161 | enum gdb_signal stop_signal) |
| 162 | { |
| 163 | struct gdbarch *gdbarch = get_regcache_arch (regcache); |
| 164 | struct fbsd_collect_regset_section_cb_data data; |
| 165 | |
| 166 | data.regcache = regcache; |
| 167 | data.obfd = obfd; |
| 168 | data.note_data = note_data; |
| 169 | data.note_size = note_size; |
| 170 | data.stop_signal = stop_signal; |
| 171 | data.abort_iteration = 0; |
| 172 | data.lwp = ptid_get_lwp (ptid); |
| 173 | |
| 174 | gdbarch_iterate_over_regset_sections (gdbarch, |
| 175 | fbsd_collect_regset_section_cb, |
| 176 | &data, regcache); |
| 177 | return data.note_data; |
| 178 | } |
| 179 | |
| 180 | struct fbsd_corefile_thread_data |
| 181 | { |
| 182 | struct gdbarch *gdbarch; |
| 183 | bfd *obfd; |
| 184 | char *note_data; |
| 185 | int *note_size; |
| 186 | enum gdb_signal stop_signal; |
| 187 | }; |
| 188 | |
| 189 | /* Records the thread's register state for the corefile note |
| 190 | section. */ |
| 191 | |
| 192 | static void |
| 193 | fbsd_corefile_thread (struct thread_info *info, |
| 194 | struct fbsd_corefile_thread_data *args) |
| 195 | { |
| 196 | struct cleanup *old_chain; |
| 197 | struct regcache *regcache; |
| 198 | |
| 199 | regcache = get_thread_arch_regcache (info->ptid, args->gdbarch); |
| 200 | |
| 201 | old_chain = save_inferior_ptid (); |
| 202 | inferior_ptid = info->ptid; |
| 203 | target_fetch_registers (regcache, -1); |
| 204 | do_cleanups (old_chain); |
| 205 | |
| 206 | args->note_data = fbsd_collect_thread_registers |
| 207 | (regcache, info->ptid, args->obfd, args->note_data, |
| 208 | args->note_size, args->stop_signal); |
| 209 | } |
| 210 | |
| 211 | /* Create appropriate note sections for a corefile, returning them in |
| 212 | allocated memory. */ |
| 213 | |
| 214 | static char * |
| 215 | fbsd_make_corefile_notes (struct gdbarch *gdbarch, bfd *obfd, int *note_size) |
| 216 | { |
| 217 | struct fbsd_corefile_thread_data thread_args; |
| 218 | char *note_data = NULL; |
| 219 | Elf_Internal_Ehdr *i_ehdrp; |
| 220 | struct thread_info *curr_thr, *signalled_thr, *thr; |
| 221 | |
| 222 | /* Put a "FreeBSD" label in the ELF header. */ |
| 223 | i_ehdrp = elf_elfheader (obfd); |
| 224 | i_ehdrp->e_ident[EI_OSABI] = ELFOSABI_FREEBSD; |
| 225 | |
| 226 | gdb_assert (gdbarch_iterate_over_regset_sections_p (gdbarch)); |
| 227 | |
| 228 | if (get_exec_file (0)) |
| 229 | { |
| 230 | const char *fname = lbasename (get_exec_file (0)); |
| 231 | char *psargs = xstrdup (fname); |
| 232 | |
| 233 | if (get_inferior_args ()) |
| 234 | psargs = reconcat (psargs, psargs, " ", get_inferior_args (), |
| 235 | (char *) NULL); |
| 236 | |
| 237 | note_data = elfcore_write_prpsinfo (obfd, note_data, note_size, |
| 238 | fname, psargs); |
| 239 | } |
| 240 | |
| 241 | /* Thread register information. */ |
| 242 | TRY |
| 243 | { |
| 244 | update_thread_list (); |
| 245 | } |
| 246 | CATCH (e, RETURN_MASK_ERROR) |
| 247 | { |
| 248 | exception_print (gdb_stderr, e); |
| 249 | } |
| 250 | END_CATCH |
| 251 | |
| 252 | /* Like the kernel, prefer dumping the signalled thread first. |
| 253 | "First thread" is what tools use to infer the signalled thread. |
| 254 | In case there's more than one signalled thread, prefer the |
| 255 | current thread, if it is signalled. */ |
| 256 | curr_thr = inferior_thread (); |
| 257 | if (curr_thr->suspend.stop_signal != GDB_SIGNAL_0) |
| 258 | signalled_thr = curr_thr; |
| 259 | else |
| 260 | { |
| 261 | signalled_thr = iterate_over_threads (find_signalled_thread, NULL); |
| 262 | if (signalled_thr == NULL) |
| 263 | signalled_thr = curr_thr; |
| 264 | } |
| 265 | |
| 266 | thread_args.gdbarch = gdbarch; |
| 267 | thread_args.obfd = obfd; |
| 268 | thread_args.note_data = note_data; |
| 269 | thread_args.note_size = note_size; |
| 270 | thread_args.stop_signal = signalled_thr->suspend.stop_signal; |
| 271 | |
| 272 | fbsd_corefile_thread (signalled_thr, &thread_args); |
| 273 | ALL_NON_EXITED_THREADS (thr) |
| 274 | { |
| 275 | if (thr == signalled_thr) |
| 276 | continue; |
| 277 | if (ptid_get_pid (thr->ptid) != ptid_get_pid (inferior_ptid)) |
| 278 | continue; |
| 279 | |
| 280 | fbsd_corefile_thread (thr, &thread_args); |
| 281 | } |
| 282 | |
| 283 | note_data = thread_args.note_data; |
| 284 | |
| 285 | return note_data; |
| 286 | } |
| 287 | |
| 288 | /* Print descriptions of FreeBSD-specific AUXV entries to FILE. */ |
| 289 | |
| 290 | static void |
| 291 | fbsd_print_auxv_entry (struct gdbarch *gdbarch, struct ui_file *file, |
| 292 | CORE_ADDR type, CORE_ADDR val) |
| 293 | { |
| 294 | const char *name; |
| 295 | const char *description; |
| 296 | enum auxv_format format; |
| 297 | |
| 298 | switch (type) |
| 299 | { |
| 300 | #define _TAGNAME(tag) #tag |
| 301 | #define TAGNAME(tag) _TAGNAME(AT_##tag) |
| 302 | #define TAG(tag, text, kind) \ |
| 303 | case AT_FREEBSD_##tag: name = TAGNAME(tag); description = text; format = kind; break |
| 304 | TAG (EXECPATH, _("Executable path"), AUXV_FORMAT_STR); |
| 305 | TAG (CANARY, _("Canary for SSP"), AUXV_FORMAT_HEX); |
| 306 | TAG (CANARYLEN, ("Length of the SSP canary"), AUXV_FORMAT_DEC); |
| 307 | TAG (OSRELDATE, _("OSRELDATE"), AUXV_FORMAT_DEC); |
| 308 | TAG (NCPUS, _("Number of CPUs"), AUXV_FORMAT_DEC); |
| 309 | TAG (PAGESIZES, _("Pagesizes"), AUXV_FORMAT_HEX); |
| 310 | TAG (PAGESIZESLEN, _("Number of pagesizes"), AUXV_FORMAT_DEC); |
| 311 | TAG (TIMEKEEP, _("Pointer to timehands"), AUXV_FORMAT_HEX); |
| 312 | TAG (STACKPROT, _("Initial stack protection"), AUXV_FORMAT_HEX); |
| 313 | default: |
| 314 | default_print_auxv_entry (gdbarch, file, type, val); |
| 315 | return; |
| 316 | } |
| 317 | |
| 318 | fprint_auxv_entry (file, name, description, format, type, val); |
| 319 | } |
| 320 | |
| 321 | /* Implement the "get_syscall_number" gdbarch method. */ |
| 322 | |
| 323 | static LONGEST |
| 324 | fbsd_get_syscall_number (struct gdbarch *gdbarch, |
| 325 | ptid_t ptid) |
| 326 | { |
| 327 | |
| 328 | /* FreeBSD doesn't use gdbarch_get_syscall_number since FreeBSD |
| 329 | native targets fetch the system call number from the |
| 330 | 'pl_syscall_code' member of struct ptrace_lwpinfo in fbsd_wait. |
| 331 | However, system call catching requires this function to be |
| 332 | set. */ |
| 333 | |
| 334 | internal_error (__FILE__, __LINE__, _("fbsd_get_sycall_number called")); |
| 335 | } |
| 336 | |
| 337 | /* To be called from GDB_OSABI_FREEBSD_ELF handlers. */ |
| 338 | |
| 339 | void |
| 340 | fbsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) |
| 341 | { |
| 342 | set_gdbarch_core_pid_to_str (gdbarch, fbsd_core_pid_to_str); |
| 343 | set_gdbarch_core_thread_name (gdbarch, fbsd_core_thread_name); |
| 344 | set_gdbarch_make_corefile_notes (gdbarch, fbsd_make_corefile_notes); |
| 345 | set_gdbarch_print_auxv_entry (gdbarch, fbsd_print_auxv_entry); |
| 346 | |
| 347 | /* `catch syscall' */ |
| 348 | set_xml_syscall_file_name (gdbarch, "syscalls/freebsd.xml"); |
| 349 | set_gdbarch_get_syscall_number (gdbarch, fbsd_get_syscall_number); |
| 350 | } |