1 /* $NetBSD: dd.c,v 1.40 2007/04/29 20:23:34 msaitoh Exp $ */ 2 3 /*- 4 * Copyright (c) 1991, 1993, 1994 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Keith Muller of the University of California, San Diego and Lance 9 * Visser of Convex Computer Corporation. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 #include <sys/cdefs.h> 37 #ifndef lint 38 __COPYRIGHT("@(#) Copyright (c) 1991, 1993, 1994\n\ 39 The Regents of the University of California. All rights reserved.\n"); 40 #endif /* not lint */ 41 42 #ifndef lint 43 #if 0 44 static char sccsid[] = "@(#)dd.c 8.5 (Berkeley) 4/2/94"; 45 #else 46 __RCSID("$NetBSD: dd.c,v 1.40 2007/04/29 20:23:34 msaitoh Exp $"); 47 #endif 48 #endif /* not lint */ 49 50 #include <sys/param.h> 51 #include <sys/stat.h> 52 #include <sys/ioctl.h> 53 #include <sys/mtio.h> 54 #include <sys/time.h> 55 56 #include <ctype.h> 57 #include <err.h> 58 #include <errno.h> 59 #include <fcntl.h> 60 #include <signal.h> 61 #include <stdio.h> 62 #include <stdlib.h> 63 #include <string.h> 64 #include <unistd.h> 65 66 #include "dd.h" 67 #include "extern.h" 68 69 static void dd_close(void); 70 static void dd_in(void); 71 static void getfdtype(IO *); 72 static int redup_clean_fd(int); 73 static void setup(void); 74 75 int main(int, char *[]); 76 77 IO in, out; /* input/output state */ 78 STAT st; /* statistics */ 79 void (*cfunc)(void); /* conversion function */ 80 uint64_t cpy_cnt; /* # of blocks to copy */ 81 static off_t pending = 0; /* pending seek if sparse */ 82 u_int ddflags; /* conversion options */ 83 uint64_t cbsz; /* conversion block size */ 84 u_int files_cnt = 1; /* # of files to copy */ 85 uint64_t progress = 0; /* display sign of life */ 86 const u_char *ctab; /* conversion table */ 87 sigset_t infoset; /* a set blocking SIGINFO */ 88 89 int 90 main(int argc, char *argv[]) 91 { 92 int ch; 93 94 while ((ch = getopt(argc, argv, "")) != -1) { 95 switch (ch) { 96 default: 97 errx(EXIT_FAILURE, "usage: dd [operand ...]"); 98 /* NOTREACHED */ 99 } 100 } 101 argc -= (optind - 1); 102 argv += (optind - 1); 103 104 jcl(argv); 105 setup(); 106 107 (void)signal(SIGINFO, summaryx); 108 (void)signal(SIGINT, terminate); 109 (void)sigemptyset(&infoset); 110 (void)sigaddset(&infoset, SIGINFO); 111 112 (void)atexit(summary); 113 114 while (files_cnt--) 115 dd_in(); 116 117 dd_close(); 118 exit(0); 119 /* NOTREACHED */ 120 } 121 122 static void 123 setup(void) 124 { 125 126 if (in.name == NULL) { 127 in.name = "stdin"; 128 in.fd = STDIN_FILENO; 129 } else { 130 in.fd = open(in.name, O_RDONLY, 0); 131 if (in.fd < 0) 132 err(EXIT_FAILURE, "%s", in.name); 133 /* NOTREACHED */ 134 135 /* Ensure in.fd is outside the stdio descriptor range */ 136 in.fd = redup_clean_fd(in.fd); 137 } 138 139 getfdtype(&in); 140 141 if (files_cnt > 1 && !(in.flags & ISTAPE)) { 142 errx(EXIT_FAILURE, "files is not supported for non-tape devices"); 143 /* NOTREACHED */ 144 } 145 146 if (out.name == NULL) { 147 /* No way to check for read access here. */ 148 out.fd = STDOUT_FILENO; 149 out.name = "stdout"; 150 } else { 151 #define OFLAGS \ 152 (O_CREAT | (ddflags & (C_SEEK | C_NOTRUNC) ? 0 : O_TRUNC)) 153 out.fd = open(out.name, O_RDWR | OFLAGS, DEFFILEMODE); 154 /* 155 * May not have read access, so try again with write only. 156 * Without read we may have a problem if output also does 157 * not support seeks. 158 */ 159 if (out.fd < 0) { 160 out.fd = open(out.name, O_WRONLY | OFLAGS, DEFFILEMODE); 161 out.flags |= NOREAD; 162 } 163 if (out.fd < 0) { 164 err(EXIT_FAILURE, "%s", out.name); 165 /* NOTREACHED */ 166 } 167 168 /* Ensure out.fd is outside the stdio descriptor range */ 169 out.fd = redup_clean_fd(out.fd); 170 } 171 172 getfdtype(&out); 173 174 /* 175 * Allocate space for the input and output buffers. If not doing 176 * record oriented I/O, only need a single buffer. 177 */ 178 if (!(ddflags & (C_BLOCK|C_UNBLOCK))) { 179 if ((in.db = malloc(out.dbsz + in.dbsz - 1)) == NULL) { 180 err(EXIT_FAILURE, NULL); 181 /* NOTREACHED */ 182 } 183 out.db = in.db; 184 } else if ((in.db = 185 malloc((u_int)(MAX(in.dbsz, cbsz) + cbsz))) == NULL || 186 (out.db = malloc((u_int)(out.dbsz + cbsz))) == NULL) { 187 err(EXIT_FAILURE, NULL); 188 /* NOTREACHED */ 189 } 190 in.dbp = in.db; 191 out.dbp = out.db; 192 193 /* Position the input/output streams. */ 194 if (in.offset) 195 pos_in(); 196 if (out.offset) 197 pos_out(); 198 199 /* 200 * Truncate the output file; ignore errors because it fails on some 201 * kinds of output files, tapes, for example. 202 */ 203 if ((ddflags & (C_OF | C_SEEK | C_NOTRUNC)) == (C_OF | C_SEEK)) 204 (void)ftruncate(out.fd, (off_t)out.offset * out.dbsz); 205 206 /* 207 * If converting case at the same time as another conversion, build a 208 * table that does both at once. If just converting case, use the 209 * built-in tables. 210 */ 211 if (ddflags & (C_LCASE|C_UCASE)) { 212 #ifdef NO_CONV 213 /* Should not get here, but just in case... */ 214 errx(EXIT_FAILURE, "case conv and -DNO_CONV"); 215 /* NOTREACHED */ 216 #else /* NO_CONV */ 217 u_int cnt; 218 219 if (ddflags & C_ASCII || ddflags & C_EBCDIC) { 220 if (ddflags & C_LCASE) { 221 for (cnt = 0; cnt < 256; ++cnt) 222 casetab[cnt] = tolower(ctab[cnt]); 223 } else { 224 for (cnt = 0; cnt < 256; ++cnt) 225 casetab[cnt] = toupper(ctab[cnt]); 226 } 227 } else { 228 if (ddflags & C_LCASE) { 229 for (cnt = 0; cnt < 256; ++cnt) 230 casetab[cnt] = tolower(cnt); 231 } else { 232 for (cnt = 0; cnt < 256; ++cnt) 233 casetab[cnt] = toupper(cnt); 234 } 235 } 236 237 ctab = casetab; 238 #endif /* NO_CONV */ 239 } 240 241 (void)gettimeofday(&st.start, NULL); /* Statistics timestamp. */ 242 } 243 244 static void 245 getfdtype(IO *io) 246 { 247 struct mtget mt; 248 struct stat sb; 249 250 if (fstat(io->fd, &sb)) { 251 err(EXIT_FAILURE, "%s", io->name); 252 /* NOTREACHED */ 253 } 254 if (S_ISCHR(sb.st_mode)) 255 io->flags |= ioctl(io->fd, MTIOCGET, &mt) ? ISCHR : ISTAPE; 256 else if (lseek(io->fd, (off_t)0, SEEK_CUR) == -1 && errno == ESPIPE) 257 io->flags |= ISPIPE; /* XXX fixed in 4.4BSD */ 258 } 259 260 /* 261 * Move the parameter file descriptor to a descriptor that is outside the 262 * stdio descriptor range, if necessary. This is required to avoid 263 * accidentally outputting completion or error messages into the 264 * output file that were intended for the tty. 265 */ 266 static int 267 redup_clean_fd(int fd) 268 { 269 int newfd; 270 271 if (fd != STDIN_FILENO && fd != STDOUT_FILENO && 272 fd != STDERR_FILENO) 273 /* File descriptor is ok, return immediately. */ 274 return fd; 275 276 /* 277 * 3 is the first descriptor greater than STD*_FILENO. Any 278 * free descriptor valued 3 or above is acceptable... 279 */ 280 newfd = fcntl(fd, F_DUPFD, 3); 281 if (newfd < 0) { 282 err(EXIT_FAILURE, "dupfd IO"); 283 /* NOTREACHED */ 284 } 285 286 close(fd); 287 288 return newfd; 289 } 290 291 static void 292 dd_in(void) 293 { 294 int flags; 295 int64_t n; 296 297 for (flags = ddflags;;) { 298 if (cpy_cnt && (st.in_full + st.in_part) >= cpy_cnt) 299 return; 300 301 /* 302 * Clear the buffer first if doing "sync" on input. 303 * If doing block operations use spaces. This will 304 * affect not only the C_NOERROR case, but also the 305 * last partial input block which should be padded 306 * with zero and not garbage. 307 */ 308 if (flags & C_SYNC) { 309 if (flags & (C_BLOCK|C_UNBLOCK)) 310 (void)memset(in.dbp, ' ', in.dbsz); 311 else 312 (void)memset(in.dbp, 0, in.dbsz); 313 } 314 315 n = read(in.fd, in.dbp, in.dbsz); 316 if (n == 0) { 317 in.dbrcnt = 0; 318 return; 319 } 320 321 /* Read error. */ 322 if (n < 0) { 323 324 /* 325 * If noerror not specified, die. POSIX requires that 326 * the warning message be followed by an I/O display. 327 */ 328 if (!(flags & C_NOERROR)) { 329 err(EXIT_FAILURE, "%s", in.name); 330 /* NOTREACHED */ 331 } 332 warn("%s", in.name); 333 summary(); 334 335 /* 336 * If it's not a tape drive or a pipe, seek past the 337 * error. If your OS doesn't do the right thing for 338 * raw disks this section should be modified to re-read 339 * in sector size chunks. 340 */ 341 if (!(in.flags & (ISPIPE|ISTAPE)) && 342 lseek(in.fd, (off_t)in.dbsz, SEEK_CUR)) 343 warn("%s", in.name); 344 345 /* If sync not specified, omit block and continue. */ 346 if (!(ddflags & C_SYNC)) 347 continue; 348 349 /* Read errors count as full blocks. */ 350 in.dbcnt += in.dbrcnt = in.dbsz; 351 ++st.in_full; 352 353 /* Handle full input blocks. */ 354 } else if (n == in.dbsz) { 355 in.dbcnt += in.dbrcnt = n; 356 ++st.in_full; 357 358 /* Handle partial input blocks. */ 359 } else { 360 /* If sync, use the entire block. */ 361 if (ddflags & C_SYNC) 362 in.dbcnt += in.dbrcnt = in.dbsz; 363 else 364 in.dbcnt += in.dbrcnt = n; 365 ++st.in_part; 366 } 367 368 /* 369 * POSIX states that if bs is set and no other conversions 370 * than noerror, notrunc or sync are specified, the block 371 * is output without buffering as it is read. 372 */ 373 if (ddflags & C_BS) { 374 out.dbcnt = in.dbcnt; 375 dd_out(1); 376 in.dbcnt = 0; 377 continue; 378 } 379 380 if (ddflags & C_SWAB) { 381 if ((n = in.dbrcnt) & 1) { 382 ++st.swab; 383 --n; 384 } 385 swab(in.dbp, in.dbp, n); 386 } 387 388 in.dbp += in.dbrcnt; 389 (*cfunc)(); 390 } 391 } 392 393 /* 394 * Cleanup any remaining I/O and flush output. If necessary, output file 395 * is truncated. 396 */ 397 static void 398 dd_close(void) 399 { 400 401 if (cfunc == def) 402 def_close(); 403 else if (cfunc == block) 404 block_close(); 405 else if (cfunc == unblock) 406 unblock_close(); 407 if (ddflags & C_OSYNC && out.dbcnt < out.dbsz) { 408 (void)memset(out.dbp, 0, out.dbsz - out.dbcnt); 409 out.dbcnt = out.dbsz; 410 } 411 /* If there are pending sparse blocks, make sure 412 * to write out the final block un-sparse 413 */ 414 if ((out.dbcnt == 0) && pending) { 415 memset(out.db, 0, out.dbsz); 416 out.dbcnt = out.dbsz; 417 out.dbp = out.db + out.dbcnt; 418 pending -= out.dbsz; 419 } 420 if (out.dbcnt) 421 dd_out(1); 422 423 /* 424 * Reporting nfs write error may be defered until next 425 * write(2) or close(2) system call. So, we need to do an 426 * extra check. If an output is stdout, the file structure 427 * may be shared among with other processes and close(2) just 428 * decreases the reference count. 429 */ 430 if (out.fd == STDOUT_FILENO && fsync(out.fd) == -1 && errno != EINVAL) { 431 err(EXIT_FAILURE, "fsync stdout"); 432 /* NOTREACHED */ 433 } 434 if (close(out.fd) == -1) { 435 err(EXIT_FAILURE, "close"); 436 /* NOTREACHED */ 437 } 438 } 439 440 void 441 dd_out(int force) 442 { 443 static int warned; 444 int64_t cnt, n, nw; 445 u_char *outp; 446 447 /* 448 * Write one or more blocks out. The common case is writing a full 449 * output block in a single write; increment the full block stats. 450 * Otherwise, we're into partial block writes. If a partial write, 451 * and it's a character device, just warn. If a tape device, quit. 452 * 453 * The partial writes represent two cases. 1: Where the input block 454 * was less than expected so the output block was less than expected. 455 * 2: Where the input block was the right size but we were forced to 456 * write the block in multiple chunks. The original versions of dd(1) 457 * never wrote a block in more than a single write, so the latter case 458 * never happened. 459 * 460 * One special case is if we're forced to do the write -- in that case 461 * we play games with the buffer size, and it's usually a partial write. 462 */ 463 outp = out.db; 464 for (n = force ? out.dbcnt : out.dbsz;; n = out.dbsz) { 465 for (cnt = n;; cnt -= nw) { 466 467 if (!force && ddflags & C_SPARSE) { 468 int sparse, i; 469 sparse = 1; /* Is buffer sparse? */ 470 for (i = 0; i < cnt; i++) 471 if (outp[i] != 0) { 472 sparse = 0; 473 break; 474 } 475 if (sparse) { 476 pending += cnt; 477 outp += cnt; 478 nw = 0; 479 break; 480 } 481 } 482 if (pending != 0) { 483 if (lseek(out.fd, pending, SEEK_CUR) == 484 -1) 485 err(EXIT_FAILURE, "%s: seek error creating sparse file", 486 out.name); 487 } 488 nw = bwrite(out.fd, outp, cnt); 489 if (nw <= 0) { 490 if (nw == 0) 491 errx(EXIT_FAILURE, 492 "%s: end of device", out.name); 493 /* NOTREACHED */ 494 if (errno != EINTR) 495 err(EXIT_FAILURE, "%s", out.name); 496 /* NOTREACHED */ 497 nw = 0; 498 } 499 if (pending) { 500 st.bytes += pending; 501 st.sparse += pending/out.dbsz; 502 st.out_full += pending/out.dbsz; 503 pending = 0; 504 } 505 outp += nw; 506 st.bytes += nw; 507 if (nw == n) { 508 if (n != out.dbsz) 509 ++st.out_part; 510 else 511 ++st.out_full; 512 break; 513 } 514 ++st.out_part; 515 if (nw == cnt) 516 break; 517 if (out.flags & ISCHR && !warned) { 518 warned = 1; 519 warnx("%s: short write on character device", out.name); 520 } 521 if (out.flags & ISTAPE) 522 errx(EXIT_FAILURE, 523 "%s: short write on tape device", out.name); 524 /* NOTREACHED */ 525 526 } 527 if ((out.dbcnt -= n) < out.dbsz) 528 break; 529 } 530 531 /* Reassemble the output block. */ 532 if (out.dbcnt) 533 (void)memmove(out.db, out.dbp - out.dbcnt, out.dbcnt); 534 out.dbp = out.db + out.dbcnt; 535 536 if (progress && (st.out_full + st.out_part) % progress == 0) 537 (void)write(STDERR_FILENO, ".", 1); 538 } 539 540 /* 541 * A protected against SIGINFO write 542 */ 543 ssize_t 544 bwrite(int fd, const void *buf, size_t len) 545 { 546 sigset_t oset; 547 ssize_t rv; 548 int oerrno; 549 550 (void)sigprocmask(SIG_BLOCK, &infoset, &oset); 551 rv = write(fd, buf, len); 552 oerrno = errno; 553 (void)sigprocmask(SIG_SETMASK, &oset, NULL); 554 errno = oerrno; 555 return (rv); 556 } 557