| 1 | /* Default child (native) target interface, for GDB when running under |
| 2 | Unix. |
| 3 | |
| 4 | Copyright (C) 1988-2014 Free Software Foundation, Inc. |
| 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 3 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, see <http://www.gnu.org/licenses/>. */ |
| 20 | |
| 21 | #include "defs.h" |
| 22 | #include "regcache.h" |
| 23 | #include "memattr.h" |
| 24 | #include "symtab.h" |
| 25 | #include "target.h" |
| 26 | #include "inferior.h" |
| 27 | #include <string.h> |
| 28 | #include <sys/stat.h> |
| 29 | #include "inf-child.h" |
| 30 | #include "gdb/fileio.h" |
| 31 | #include "agent.h" |
| 32 | #include "gdb_wait.h" |
| 33 | #include "filestuff.h" |
| 34 | |
| 35 | #include <sys/types.h> |
| 36 | #include <fcntl.h> |
| 37 | #include <unistd.h> |
| 38 | |
| 39 | /* Helper function for child_wait and the derivatives of child_wait. |
| 40 | HOSTSTATUS is the waitstatus from wait() or the equivalent; store our |
| 41 | translation of that in OURSTATUS. */ |
| 42 | void |
| 43 | store_waitstatus (struct target_waitstatus *ourstatus, int hoststatus) |
| 44 | { |
| 45 | if (WIFEXITED (hoststatus)) |
| 46 | { |
| 47 | ourstatus->kind = TARGET_WAITKIND_EXITED; |
| 48 | ourstatus->value.integer = WEXITSTATUS (hoststatus); |
| 49 | } |
| 50 | else if (!WIFSTOPPED (hoststatus)) |
| 51 | { |
| 52 | ourstatus->kind = TARGET_WAITKIND_SIGNALLED; |
| 53 | ourstatus->value.sig = gdb_signal_from_host (WTERMSIG (hoststatus)); |
| 54 | } |
| 55 | else |
| 56 | { |
| 57 | ourstatus->kind = TARGET_WAITKIND_STOPPED; |
| 58 | ourstatus->value.sig = gdb_signal_from_host (WSTOPSIG (hoststatus)); |
| 59 | } |
| 60 | } |
| 61 | |
| 62 | /* Fetch register REGNUM from the inferior. If REGNUM is -1, do this |
| 63 | for all registers. */ |
| 64 | |
| 65 | static void |
| 66 | inf_child_fetch_inferior_registers (struct target_ops *ops, |
| 67 | struct regcache *regcache, int regnum) |
| 68 | { |
| 69 | if (regnum == -1) |
| 70 | { |
| 71 | for (regnum = 0; |
| 72 | regnum < gdbarch_num_regs (get_regcache_arch (regcache)); |
| 73 | regnum++) |
| 74 | regcache_raw_supply (regcache, regnum, NULL); |
| 75 | } |
| 76 | else |
| 77 | regcache_raw_supply (regcache, regnum, NULL); |
| 78 | } |
| 79 | |
| 80 | /* Store register REGNUM back into the inferior. If REGNUM is -1, do |
| 81 | this for all registers (including the floating point registers). */ |
| 82 | |
| 83 | static void |
| 84 | inf_child_store_inferior_registers (struct target_ops *ops, |
| 85 | struct regcache *regcache, int regnum) |
| 86 | { |
| 87 | } |
| 88 | |
| 89 | static void |
| 90 | inf_child_post_attach (int pid) |
| 91 | { |
| 92 | /* This version of Unix doesn't require a meaningful "post attach" |
| 93 | operation by a debugger. */ |
| 94 | } |
| 95 | |
| 96 | /* Get ready to modify the registers array. On machines which store |
| 97 | individual registers, this doesn't need to do anything. On |
| 98 | machines which store all the registers in one fell swoop, this |
| 99 | makes sure that registers contains all the registers from the |
| 100 | program being debugged. */ |
| 101 | |
| 102 | static void |
| 103 | inf_child_prepare_to_store (struct regcache *regcache) |
| 104 | { |
| 105 | } |
| 106 | |
| 107 | static void |
| 108 | inf_child_open (char *arg, int from_tty) |
| 109 | { |
| 110 | error (_("Use the \"run\" command to start a Unix child process.")); |
| 111 | } |
| 112 | |
| 113 | static void |
| 114 | inf_child_post_startup_inferior (ptid_t ptid) |
| 115 | { |
| 116 | /* This version of Unix doesn't require a meaningful "post startup |
| 117 | inferior" operation by a debugger. */ |
| 118 | } |
| 119 | |
| 120 | static int |
| 121 | inf_child_follow_fork (struct target_ops *ops, int follow_child, |
| 122 | int detach_fork) |
| 123 | { |
| 124 | /* This version of Unix doesn't support following fork or vfork |
| 125 | events. */ |
| 126 | return 0; |
| 127 | } |
| 128 | |
| 129 | static int |
| 130 | inf_child_can_run (void) |
| 131 | { |
| 132 | return 1; |
| 133 | } |
| 134 | |
| 135 | static char * |
| 136 | inf_child_pid_to_exec_file (int pid) |
| 137 | { |
| 138 | /* This version of Unix doesn't support translation of a process ID |
| 139 | to the filename of the executable file. */ |
| 140 | return NULL; |
| 141 | } |
| 142 | |
| 143 | |
| 144 | /* Target file operations. */ |
| 145 | |
| 146 | static int |
| 147 | inf_child_fileio_open_flags_to_host (int fileio_open_flags, int *open_flags_p) |
| 148 | { |
| 149 | int open_flags = 0; |
| 150 | |
| 151 | if (fileio_open_flags & ~FILEIO_O_SUPPORTED) |
| 152 | return -1; |
| 153 | |
| 154 | if (fileio_open_flags & FILEIO_O_CREAT) |
| 155 | open_flags |= O_CREAT; |
| 156 | if (fileio_open_flags & FILEIO_O_EXCL) |
| 157 | open_flags |= O_EXCL; |
| 158 | if (fileio_open_flags & FILEIO_O_TRUNC) |
| 159 | open_flags |= O_TRUNC; |
| 160 | if (fileio_open_flags & FILEIO_O_APPEND) |
| 161 | open_flags |= O_APPEND; |
| 162 | if (fileio_open_flags & FILEIO_O_RDONLY) |
| 163 | open_flags |= O_RDONLY; |
| 164 | if (fileio_open_flags & FILEIO_O_WRONLY) |
| 165 | open_flags |= O_WRONLY; |
| 166 | if (fileio_open_flags & FILEIO_O_RDWR) |
| 167 | open_flags |= O_RDWR; |
| 168 | /* On systems supporting binary and text mode, always open files in |
| 169 | binary mode. */ |
| 170 | #ifdef O_BINARY |
| 171 | open_flags |= O_BINARY; |
| 172 | #endif |
| 173 | |
| 174 | *open_flags_p = open_flags; |
| 175 | return 0; |
| 176 | } |
| 177 | |
| 178 | static int |
| 179 | inf_child_errno_to_fileio_error (int errnum) |
| 180 | { |
| 181 | switch (errnum) |
| 182 | { |
| 183 | case EPERM: |
| 184 | return FILEIO_EPERM; |
| 185 | case ENOENT: |
| 186 | return FILEIO_ENOENT; |
| 187 | case EINTR: |
| 188 | return FILEIO_EINTR; |
| 189 | case EIO: |
| 190 | return FILEIO_EIO; |
| 191 | case EBADF: |
| 192 | return FILEIO_EBADF; |
| 193 | case EACCES: |
| 194 | return FILEIO_EACCES; |
| 195 | case EFAULT: |
| 196 | return FILEIO_EFAULT; |
| 197 | case EBUSY: |
| 198 | return FILEIO_EBUSY; |
| 199 | case EEXIST: |
| 200 | return FILEIO_EEXIST; |
| 201 | case ENODEV: |
| 202 | return FILEIO_ENODEV; |
| 203 | case ENOTDIR: |
| 204 | return FILEIO_ENOTDIR; |
| 205 | case EISDIR: |
| 206 | return FILEIO_EISDIR; |
| 207 | case EINVAL: |
| 208 | return FILEIO_EINVAL; |
| 209 | case ENFILE: |
| 210 | return FILEIO_ENFILE; |
| 211 | case EMFILE: |
| 212 | return FILEIO_EMFILE; |
| 213 | case EFBIG: |
| 214 | return FILEIO_EFBIG; |
| 215 | case ENOSPC: |
| 216 | return FILEIO_ENOSPC; |
| 217 | case ESPIPE: |
| 218 | return FILEIO_ESPIPE; |
| 219 | case EROFS: |
| 220 | return FILEIO_EROFS; |
| 221 | case ENOSYS: |
| 222 | return FILEIO_ENOSYS; |
| 223 | case ENAMETOOLONG: |
| 224 | return FILEIO_ENAMETOOLONG; |
| 225 | } |
| 226 | return FILEIO_EUNKNOWN; |
| 227 | } |
| 228 | |
| 229 | /* Open FILENAME on the target, using FLAGS and MODE. Return a |
| 230 | target file descriptor, or -1 if an error occurs (and set |
| 231 | *TARGET_ERRNO). */ |
| 232 | static int |
| 233 | inf_child_fileio_open (const char *filename, int flags, int mode, |
| 234 | int *target_errno) |
| 235 | { |
| 236 | int nat_flags; |
| 237 | int fd; |
| 238 | |
| 239 | if (inf_child_fileio_open_flags_to_host (flags, &nat_flags) == -1) |
| 240 | { |
| 241 | *target_errno = FILEIO_EINVAL; |
| 242 | return -1; |
| 243 | } |
| 244 | |
| 245 | /* We do not need to convert MODE, since the fileio protocol uses |
| 246 | the standard values. */ |
| 247 | fd = gdb_open_cloexec (filename, nat_flags, mode); |
| 248 | if (fd == -1) |
| 249 | *target_errno = inf_child_errno_to_fileio_error (errno); |
| 250 | |
| 251 | return fd; |
| 252 | } |
| 253 | |
| 254 | /* Write up to LEN bytes from WRITE_BUF to FD on the target. |
| 255 | Return the number of bytes written, or -1 if an error occurs |
| 256 | (and set *TARGET_ERRNO). */ |
| 257 | static int |
| 258 | inf_child_fileio_pwrite (int fd, const gdb_byte *write_buf, int len, |
| 259 | ULONGEST offset, int *target_errno) |
| 260 | { |
| 261 | int ret; |
| 262 | |
| 263 | #ifdef HAVE_PWRITE |
| 264 | ret = pwrite (fd, write_buf, len, (long) offset); |
| 265 | #else |
| 266 | ret = -1; |
| 267 | #endif |
| 268 | /* If we have no pwrite or it failed for this file, use lseek/write. */ |
| 269 | if (ret == -1) |
| 270 | { |
| 271 | ret = lseek (fd, (long) offset, SEEK_SET); |
| 272 | if (ret != -1) |
| 273 | ret = write (fd, write_buf, len); |
| 274 | } |
| 275 | |
| 276 | if (ret == -1) |
| 277 | *target_errno = inf_child_errno_to_fileio_error (errno); |
| 278 | |
| 279 | return ret; |
| 280 | } |
| 281 | |
| 282 | /* Read up to LEN bytes FD on the target into READ_BUF. |
| 283 | Return the number of bytes read, or -1 if an error occurs |
| 284 | (and set *TARGET_ERRNO). */ |
| 285 | static int |
| 286 | inf_child_fileio_pread (int fd, gdb_byte *read_buf, int len, |
| 287 | ULONGEST offset, int *target_errno) |
| 288 | { |
| 289 | int ret; |
| 290 | |
| 291 | #ifdef HAVE_PREAD |
| 292 | ret = pread (fd, read_buf, len, (long) offset); |
| 293 | #else |
| 294 | ret = -1; |
| 295 | #endif |
| 296 | /* If we have no pread or it failed for this file, use lseek/read. */ |
| 297 | if (ret == -1) |
| 298 | { |
| 299 | ret = lseek (fd, (long) offset, SEEK_SET); |
| 300 | if (ret != -1) |
| 301 | ret = read (fd, read_buf, len); |
| 302 | } |
| 303 | |
| 304 | if (ret == -1) |
| 305 | *target_errno = inf_child_errno_to_fileio_error (errno); |
| 306 | |
| 307 | return ret; |
| 308 | } |
| 309 | |
| 310 | /* Close FD on the target. Return 0, or -1 if an error occurs |
| 311 | (and set *TARGET_ERRNO). */ |
| 312 | static int |
| 313 | inf_child_fileio_close (int fd, int *target_errno) |
| 314 | { |
| 315 | int ret; |
| 316 | |
| 317 | ret = close (fd); |
| 318 | if (ret == -1) |
| 319 | *target_errno = inf_child_errno_to_fileio_error (errno); |
| 320 | |
| 321 | return ret; |
| 322 | } |
| 323 | |
| 324 | /* Unlink FILENAME on the target. Return 0, or -1 if an error |
| 325 | occurs (and set *TARGET_ERRNO). */ |
| 326 | static int |
| 327 | inf_child_fileio_unlink (const char *filename, int *target_errno) |
| 328 | { |
| 329 | int ret; |
| 330 | |
| 331 | ret = unlink (filename); |
| 332 | if (ret == -1) |
| 333 | *target_errno = inf_child_errno_to_fileio_error (errno); |
| 334 | |
| 335 | return ret; |
| 336 | } |
| 337 | |
| 338 | /* Read value of symbolic link FILENAME on the target. Return a |
| 339 | null-terminated string allocated via xmalloc, or NULL if an error |
| 340 | occurs (and set *TARGET_ERRNO). */ |
| 341 | static char * |
| 342 | inf_child_fileio_readlink (const char *filename, int *target_errno) |
| 343 | { |
| 344 | /* We support readlink only on systems that also provide a compile-time |
| 345 | maximum path length (PATH_MAX), at least for now. */ |
| 346 | #if defined (HAVE_READLINK) && defined (PATH_MAX) |
| 347 | char buf[PATH_MAX]; |
| 348 | int len; |
| 349 | char *ret; |
| 350 | |
| 351 | len = readlink (filename, buf, sizeof buf); |
| 352 | if (len < 0) |
| 353 | { |
| 354 | *target_errno = inf_child_errno_to_fileio_error (errno); |
| 355 | return NULL; |
| 356 | } |
| 357 | |
| 358 | ret = xmalloc (len + 1); |
| 359 | memcpy (ret, buf, len); |
| 360 | ret[len] = '\0'; |
| 361 | return ret; |
| 362 | #else |
| 363 | *target_errno = FILEIO_ENOSYS; |
| 364 | return NULL; |
| 365 | #endif |
| 366 | } |
| 367 | |
| 368 | static int |
| 369 | inf_child_use_agent (int use) |
| 370 | { |
| 371 | if (agent_loaded_p ()) |
| 372 | { |
| 373 | use_agent = use; |
| 374 | return 1; |
| 375 | } |
| 376 | else |
| 377 | return 0; |
| 378 | } |
| 379 | |
| 380 | static int |
| 381 | inf_child_can_use_agent (void) |
| 382 | { |
| 383 | return agent_loaded_p (); |
| 384 | } |
| 385 | |
| 386 | struct target_ops * |
| 387 | inf_child_target (void) |
| 388 | { |
| 389 | struct target_ops *t = XCNEW (struct target_ops); |
| 390 | |
| 391 | t->to_shortname = "child"; |
| 392 | t->to_longname = "Unix child process"; |
| 393 | t->to_doc = "Unix child process (started by the \"run\" command)."; |
| 394 | t->to_open = inf_child_open; |
| 395 | t->to_post_attach = inf_child_post_attach; |
| 396 | t->to_fetch_registers = inf_child_fetch_inferior_registers; |
| 397 | t->to_store_registers = inf_child_store_inferior_registers; |
| 398 | t->to_prepare_to_store = inf_child_prepare_to_store; |
| 399 | t->to_insert_breakpoint = memory_insert_breakpoint; |
| 400 | t->to_remove_breakpoint = memory_remove_breakpoint; |
| 401 | t->to_terminal_init = terminal_init_inferior; |
| 402 | t->to_terminal_inferior = terminal_inferior; |
| 403 | t->to_terminal_ours_for_output = terminal_ours_for_output; |
| 404 | t->to_terminal_save_ours = terminal_save_ours; |
| 405 | t->to_terminal_ours = terminal_ours; |
| 406 | t->to_terminal_info = child_terminal_info; |
| 407 | t->to_post_startup_inferior = inf_child_post_startup_inferior; |
| 408 | t->to_follow_fork = inf_child_follow_fork; |
| 409 | t->to_can_run = inf_child_can_run; |
| 410 | t->to_pid_to_exec_file = inf_child_pid_to_exec_file; |
| 411 | t->to_stratum = process_stratum; |
| 412 | t->to_has_all_memory = default_child_has_all_memory; |
| 413 | t->to_has_memory = default_child_has_memory; |
| 414 | t->to_has_stack = default_child_has_stack; |
| 415 | t->to_has_registers = default_child_has_registers; |
| 416 | t->to_has_execution = default_child_has_execution; |
| 417 | t->to_fileio_open = inf_child_fileio_open; |
| 418 | t->to_fileio_pwrite = inf_child_fileio_pwrite; |
| 419 | t->to_fileio_pread = inf_child_fileio_pread; |
| 420 | t->to_fileio_close = inf_child_fileio_close; |
| 421 | t->to_fileio_unlink = inf_child_fileio_unlink; |
| 422 | t->to_fileio_readlink = inf_child_fileio_readlink; |
| 423 | t->to_magic = OPS_MAGIC; |
| 424 | t->to_use_agent = inf_child_use_agent; |
| 425 | t->to_can_use_agent = inf_child_can_use_agent; |
| 426 | return t; |
| 427 | } |