| 1 | /* Remote target system call support. |
| 2 | Copyright 1997, 1998 Free Software Foundation, Inc. |
| 3 | Contributed by Cygnus Solutions. |
| 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 2 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 GAS; see the file COPYING. If not, write to the Free Software |
| 19 | Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ |
| 20 | |
| 21 | /* This interface isn't intended to be specific to any particular kind |
| 22 | of remote (hardware, simulator, whatever). As such, support for it |
| 23 | (e.g. sim/common/callback.c) should *not* live in the simulator source |
| 24 | tree, nor should it live in the gdb source tree. K&R C must be |
| 25 | supported. */ |
| 26 | |
| 27 | #ifdef HAVE_CONFIG_H |
| 28 | #include "config.h" |
| 29 | #endif |
| 30 | #include "ansidecl.h" |
| 31 | #include "libiberty.h" |
| 32 | #ifdef ANSI_PROTOTYPES |
| 33 | #include <stdarg.h> |
| 34 | #else |
| 35 | #include <varargs.h> |
| 36 | #endif |
| 37 | #include <stdio.h> |
| 38 | #ifdef HAVE_STDLIB_H |
| 39 | #include <stdlib.h> |
| 40 | #endif |
| 41 | #ifdef HAVE_UNISTD_H |
| 42 | #include <unistd.h> |
| 43 | #endif |
| 44 | #include <errno.h> |
| 45 | #include <fcntl.h> |
| 46 | #include <time.h> |
| 47 | #include <sys/types.h> |
| 48 | #include <sys/stat.h> |
| 49 | #include "callback.h" |
| 50 | #include "targ-vals.h" |
| 51 | |
| 52 | #ifndef ENOSYS |
| 53 | #define ENOSYS EINVAL |
| 54 | #endif |
| 55 | #ifndef ENAMETOOLONG |
| 56 | #define ENAMETOOLONG EINVAL |
| 57 | #endif |
| 58 | |
| 59 | /* Maximum length of a path name. */ |
| 60 | #ifndef MAX_PATH_LEN |
| 61 | #define MAX_PATH_LEN 1024 |
| 62 | #endif |
| 63 | |
| 64 | /* When doing file read/writes, do this many bytes at a time. */ |
| 65 | #define FILE_XFR_SIZE 4096 |
| 66 | |
| 67 | /* FIXME: for now, need to consider target word size. */ |
| 68 | #define TWORD long |
| 69 | #define TADDR unsigned long |
| 70 | |
| 71 | /* Utility of cb_syscall to fetch a path name or other string from the target. |
| 72 | The result is 0 for success or a host errno value. */ |
| 73 | |
| 74 | static int |
| 75 | get_string (cb, sc, buf, buflen, addr) |
| 76 | host_callback *cb; |
| 77 | CB_SYSCALL *sc; |
| 78 | char *buf; |
| 79 | int buflen; |
| 80 | TADDR addr; |
| 81 | { |
| 82 | char *p, *pend; |
| 83 | |
| 84 | for (p = buf, pend = buf + buflen; p < pend; ++p, ++addr) |
| 85 | { |
| 86 | /* No, it isn't expected that this would cause one transaction with |
| 87 | the remote target for each byte. The target could send the |
| 88 | path name along with the syscall request, and cache the file |
| 89 | name somewhere (or otherwise tweak this as desired). */ |
| 90 | unsigned int count = (*sc->read_mem) (cb, sc, addr, p, 1); |
| 91 | |
| 92 | if (count != 1) |
| 93 | return EINVAL; |
| 94 | if (*p == 0) |
| 95 | break; |
| 96 | } |
| 97 | if (p == pend) |
| 98 | return ENAMETOOLONG; |
| 99 | return 0; |
| 100 | } |
| 101 | |
| 102 | /* Utility of cb_syscall to fetch a path name. |
| 103 | The buffer is malloc'd and the address is stored in BUFP. |
| 104 | The result is that of get_string. |
| 105 | If an error occurs, no buffer is left malloc'd. */ |
| 106 | |
| 107 | static int |
| 108 | get_path (cb, sc, addr, bufp) |
| 109 | host_callback *cb; |
| 110 | CB_SYSCALL *sc; |
| 111 | TADDR addr; |
| 112 | char **bufp; |
| 113 | { |
| 114 | char *buf = xmalloc (MAX_PATH_LEN); |
| 115 | int result; |
| 116 | |
| 117 | result = get_string (cb, sc, buf, MAX_PATH_LEN, addr); |
| 118 | if (result == 0) |
| 119 | *bufp = buf; |
| 120 | else |
| 121 | free (buf); |
| 122 | return result; |
| 123 | } |
| 124 | |
| 125 | /* Perform a system call on behalf of the target. */ |
| 126 | |
| 127 | CB_RC |
| 128 | cb_syscall (cb, sc) |
| 129 | host_callback *cb; |
| 130 | CB_SYSCALL *sc; |
| 131 | { |
| 132 | TWORD result = 0, errcode = 0; |
| 133 | |
| 134 | if (sc->magic != CB_SYSCALL_MAGIC) |
| 135 | abort (); |
| 136 | |
| 137 | switch (cb_target_to_host_syscall (cb, sc->func)) |
| 138 | { |
| 139 | #if 0 /* FIXME: wip */ |
| 140 | case CB_SYS_argvlen : |
| 141 | { |
| 142 | /* Compute how much space is required to store the argv,envp |
| 143 | strings so that the program can allocate the space and then |
| 144 | call SYS_argv to fetch the values. */ |
| 145 | int addr_size = cb->addr_size; |
| 146 | int argc,envc,arglen,envlen; |
| 147 | const char **argv = cb->init_argv; |
| 148 | const char **envp = cb->init_envp; |
| 149 | |
| 150 | argc = arglen = 0; |
| 151 | if (argv) |
| 152 | { |
| 153 | for ( ; argv[argc]; ++argc) |
| 154 | arglen += strlen (argv[argc]) + 1; |
| 155 | } |
| 156 | envc = envlen = 0; |
| 157 | if (envp) |
| 158 | { |
| 159 | for ( ; envp[envc]; ++envc) |
| 160 | envlen += strlen (envp[envc]) + 1; |
| 161 | } |
| 162 | result = arglen + envlen; |
| 163 | break; |
| 164 | } |
| 165 | |
| 166 | case CB_SYS_argv : |
| 167 | { |
| 168 | /* Pointer to target's buffer. */ |
| 169 | TADDR tbuf = sc->arg1; |
| 170 | /* Buffer size. */ |
| 171 | int bufsize = sc->arg2; |
| 172 | /* Q is the target address of where all the strings go. */ |
| 173 | TADDR q; |
| 174 | int word_size = cb->word_size; |
| 175 | int i,argc,envc,len; |
| 176 | const char **argv = cb->init_argv; |
| 177 | const char **envp = cb->init_envp; |
| 178 | |
| 179 | argc = 0; |
| 180 | if (argv) |
| 181 | { |
| 182 | for ( ; argv[argc]; ++argc) |
| 183 | { |
| 184 | int len = strlen (argv[argc]); |
| 185 | int written = (*sc->write_mem) (cb, sc, tbuf, argv[argc], len + 1); |
| 186 | if (written != len) |
| 187 | { |
| 188 | result = -1; |
| 189 | errcode = EINVAL; |
| 190 | goto FinishSyscall; |
| 191 | } |
| 192 | tbuf = len + 1; |
| 193 | } |
| 194 | } |
| 195 | if ((*sc->write_mem) (cb, sc, tbuf, "", 1) != 1) |
| 196 | { |
| 197 | result = -1; |
| 198 | errcode = EINVAL; |
| 199 | goto FinishSyscall; |
| 200 | } |
| 201 | tbuf++; |
| 202 | envc = 0; |
| 203 | if (envp) |
| 204 | { |
| 205 | for ( ; envp[envc]; ++envc) |
| 206 | { |
| 207 | int len = strlen (envp[envc]); |
| 208 | int written = (*sc->write_mem) (cb, sc, tbuf, envp[envc], len + 1); |
| 209 | if (written != len) |
| 210 | { |
| 211 | result = -1; |
| 212 | errcode = EINVAL; |
| 213 | goto FinishSyscall; |
| 214 | } |
| 215 | tbuf = len + 1; |
| 216 | } |
| 217 | } |
| 218 | if ((*sc->write_mem) (cb, sc, tbuf, "", 1) != 1) |
| 219 | { |
| 220 | result = -1; |
| 221 | errcode = EINVAL; |
| 222 | goto FinishSyscall; |
| 223 | } |
| 224 | result = argc; |
| 225 | sc->result2 = envc; |
| 226 | break; |
| 227 | } |
| 228 | #endif /* wip */ |
| 229 | |
| 230 | case CB_SYS_exit : |
| 231 | /* Caller must catch and handle. */ |
| 232 | break; |
| 233 | |
| 234 | case CB_SYS_open : |
| 235 | { |
| 236 | char *path; |
| 237 | |
| 238 | errcode = get_path (cb, sc, sc->arg1, &path); |
| 239 | if (errcode != 0) |
| 240 | { |
| 241 | result = -1; |
| 242 | goto FinishSyscall; |
| 243 | } |
| 244 | result = (*cb->open) (cb, path, sc->arg2 /*, sc->arg3*/); |
| 245 | free (path); |
| 246 | if (result < 0) |
| 247 | goto ErrorFinish; |
| 248 | } |
| 249 | break; |
| 250 | |
| 251 | case CB_SYS_close : |
| 252 | result = (*cb->close) (cb, sc->arg1); |
| 253 | if (result < 0) |
| 254 | goto ErrorFinish; |
| 255 | break; |
| 256 | |
| 257 | case CB_SYS_read : |
| 258 | { |
| 259 | /* ??? Perfect handling of error conditions may require only one |
| 260 | call to cb->read. One can't assume all the data is |
| 261 | contiguously stored in host memory so that would require |
| 262 | malloc'ing/free'ing the space. Maybe later. */ |
| 263 | char buf[FILE_XFR_SIZE]; |
| 264 | int fd = sc->arg1; |
| 265 | TADDR addr = sc->arg2; |
| 266 | size_t count = sc->arg3; |
| 267 | size_t bytes_read = 0; |
| 268 | int bytes_written; |
| 269 | |
| 270 | while (count > 0) |
| 271 | { |
| 272 | if (fd == 0) |
| 273 | result = (int) (*cb->read_stdin) (cb, buf, |
| 274 | (count < FILE_XFR_SIZE |
| 275 | ? count : FILE_XFR_SIZE)); |
| 276 | else |
| 277 | result = (int) (*cb->read) (cb, fd, buf, |
| 278 | (count < FILE_XFR_SIZE |
| 279 | ? count : FILE_XFR_SIZE)); |
| 280 | if (result == -1) |
| 281 | goto ErrorFinish; |
| 282 | if (result == 0) /* EOF */ |
| 283 | break; |
| 284 | bytes_written = (*sc->write_mem) (cb, sc, addr, buf, result); |
| 285 | if (bytes_written != result) |
| 286 | { |
| 287 | result = -1; |
| 288 | errcode = EINVAL; |
| 289 | goto FinishSyscall; |
| 290 | } |
| 291 | bytes_read += result; |
| 292 | count -= result; |
| 293 | addr += result; |
| 294 | /* If this is a short read, don't go back for more */ |
| 295 | if (result != FILE_XFR_SIZE) |
| 296 | break; |
| 297 | } |
| 298 | result = bytes_read; |
| 299 | } |
| 300 | break; |
| 301 | |
| 302 | case CB_SYS_write : |
| 303 | { |
| 304 | /* ??? Perfect handling of error conditions may require only one |
| 305 | call to cb->write. One can't assume all the data is |
| 306 | contiguously stored in host memory so that would require |
| 307 | malloc'ing/free'ing the space. Maybe later. */ |
| 308 | char buf[FILE_XFR_SIZE]; |
| 309 | int fd = sc->arg1; |
| 310 | TADDR addr = sc->arg2; |
| 311 | size_t count = sc->arg3; |
| 312 | int bytes_read; |
| 313 | size_t bytes_written = 0; |
| 314 | |
| 315 | while (count > 0) |
| 316 | { |
| 317 | int bytes_to_read = count < FILE_XFR_SIZE ? count : FILE_XFR_SIZE; |
| 318 | bytes_read = (*sc->read_mem) (cb, sc, addr, buf, bytes_to_read); |
| 319 | if (bytes_read != bytes_to_read) |
| 320 | { |
| 321 | result = -1; |
| 322 | errcode = EINVAL; |
| 323 | goto FinishSyscall; |
| 324 | } |
| 325 | if (fd == 1) |
| 326 | { |
| 327 | result = (int) (*cb->write_stdout) (cb, buf, bytes_read); |
| 328 | (*cb->flush_stdout) (cb); |
| 329 | } |
| 330 | else if (fd == 2) |
| 331 | { |
| 332 | result = (int) (*cb->write_stderr) (cb, buf, bytes_read); |
| 333 | (*cb->flush_stderr) (cb); |
| 334 | } |
| 335 | else |
| 336 | result = (int) (*cb->write) (cb, fd, buf, bytes_read); |
| 337 | if (result == -1) |
| 338 | goto ErrorFinish; |
| 339 | bytes_written += result; |
| 340 | count -= result; |
| 341 | addr += result; |
| 342 | } |
| 343 | result = bytes_written; |
| 344 | } |
| 345 | break; |
| 346 | |
| 347 | case CB_SYS_lseek : |
| 348 | { |
| 349 | int fd = sc->arg1; |
| 350 | unsigned long offset = sc->arg2; |
| 351 | int whence = sc->arg3; |
| 352 | |
| 353 | result = (*cb->lseek) (cb, fd, offset, whence); |
| 354 | if (result < 0) |
| 355 | goto ErrorFinish; |
| 356 | } |
| 357 | break; |
| 358 | |
| 359 | case CB_SYS_unlink : |
| 360 | { |
| 361 | char *path; |
| 362 | |
| 363 | errcode = get_path (cb, sc, sc->arg1, &path); |
| 364 | if (errcode != 0) |
| 365 | { |
| 366 | result = -1; |
| 367 | goto FinishSyscall; |
| 368 | } |
| 369 | result = (*cb->unlink) (cb, path); |
| 370 | free (path); |
| 371 | if (result < 0) |
| 372 | goto ErrorFinish; |
| 373 | } |
| 374 | break; |
| 375 | |
| 376 | case CB_SYS_stat : |
| 377 | { |
| 378 | char *path,*buf; |
| 379 | int buflen; |
| 380 | struct stat statbuf; |
| 381 | TADDR addr = sc->arg2; |
| 382 | |
| 383 | errcode = get_path (cb, sc, sc->arg1, &path); |
| 384 | if (errcode != 0) |
| 385 | { |
| 386 | result = -1; |
| 387 | goto FinishSyscall; |
| 388 | } |
| 389 | result = (*cb->stat) (cb, path, &statbuf); |
| 390 | free (path); |
| 391 | if (result < 0) |
| 392 | goto ErrorFinish; |
| 393 | buflen = cb_host_to_target_stat (cb, NULL, NULL); |
| 394 | buf = xmalloc (buflen); |
| 395 | if (cb_host_to_target_stat (cb, &statbuf, buf) != buflen) |
| 396 | { |
| 397 | /* The translation failed. This is due to an internal |
| 398 | host program error, not the target's fault. */ |
| 399 | free (buf); |
| 400 | errcode = ENOSYS; |
| 401 | result = -1; |
| 402 | goto FinishSyscall; |
| 403 | } |
| 404 | if ((*sc->write_mem) (cb, sc, addr, buf, buflen) != buflen) |
| 405 | { |
| 406 | free (buf); |
| 407 | errcode = EINVAL; |
| 408 | result = -1; |
| 409 | goto FinishSyscall; |
| 410 | } |
| 411 | free (buf); |
| 412 | } |
| 413 | break; |
| 414 | |
| 415 | case CB_SYS_fstat : |
| 416 | { |
| 417 | char *buf; |
| 418 | int buflen; |
| 419 | struct stat statbuf; |
| 420 | TADDR addr = sc->arg2; |
| 421 | |
| 422 | result = (*cb->fstat) (cb, sc->arg1, &statbuf); |
| 423 | if (result < 0) |
| 424 | goto ErrorFinish; |
| 425 | buflen = cb_host_to_target_stat (cb, NULL, NULL); |
| 426 | buf = xmalloc (buflen); |
| 427 | if (cb_host_to_target_stat (cb, &statbuf, buf) != buflen) |
| 428 | { |
| 429 | /* The translation failed. This is due to an internal |
| 430 | host program error, not the target's fault. */ |
| 431 | free (buf); |
| 432 | errcode = ENOSYS; |
| 433 | result = -1; |
| 434 | goto FinishSyscall; |
| 435 | } |
| 436 | if ((*sc->write_mem) (cb, sc, addr, buf, buflen) != buflen) |
| 437 | { |
| 438 | free (buf); |
| 439 | errcode = EINVAL; |
| 440 | result = -1; |
| 441 | goto FinishSyscall; |
| 442 | } |
| 443 | free (buf); |
| 444 | } |
| 445 | break; |
| 446 | |
| 447 | case CB_SYS_time : |
| 448 | { |
| 449 | /* FIXME: May wish to change CB_SYS_time to something else. |
| 450 | We might also want gettimeofday or times, but if system calls |
| 451 | can be built on others, we can keep the number we have to support |
| 452 | here down. */ |
| 453 | time_t t = (*cb->time) (cb, (time_t *) 0); |
| 454 | result = t; |
| 455 | /* It is up to target code to process the argument to time(). */ |
| 456 | } |
| 457 | break; |
| 458 | |
| 459 | case CB_SYS_chdir : |
| 460 | case CB_SYS_chmod : |
| 461 | case CB_SYS_utime : |
| 462 | /* fall through for now */ |
| 463 | |
| 464 | default : |
| 465 | result = -1; |
| 466 | errcode = ENOSYS; |
| 467 | break; |
| 468 | } |
| 469 | |
| 470 | FinishSyscall: |
| 471 | sc->result = result; |
| 472 | if (errcode == 0) |
| 473 | sc->errcode = 0; |
| 474 | else |
| 475 | sc->errcode = cb_host_to_target_errno (cb, errcode); |
| 476 | return CB_RC_OK; |
| 477 | |
| 478 | ErrorFinish: |
| 479 | sc->result = result; |
| 480 | sc->errcode = (*cb->get_errno) (cb); |
| 481 | return CB_RC_OK; |
| 482 | } |