1 /* $NetBSD: dd.c,v 1.29 2002/09/04 04:21:54 enami 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. All advertising materials mentioning features or use of this software 20 * must display the following acknowledgement: 21 * This product includes software developed by the University of 22 * California, Berkeley and its contributors. 23 * 4. Neither the name of the University nor the names of its contributors 24 * may be used to endorse or promote products derived from this software 25 * without specific prior written permission. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 30 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 37 * SUCH DAMAGE. 38 */ 39 40 #include <sys/cdefs.h> 41 #ifndef lint 42 __COPYRIGHT("@(#) Copyright (c) 1991, 1993, 1994\n\ 43 The Regents of the University of California. All rights reserved.\n"); 44 #endif /* not lint */ 45 46 #ifndef lint 47 #if 0 48 static char sccsid[] = "@(#)dd.c 8.5 (Berkeley) 4/2/94"; 49 #else 50 __RCSID("$NetBSD: dd.c,v 1.29 2002/09/04 04:21:54 enami Exp $"); 51 #endif 52 #endif /* not lint */ 53 54 #include <sys/param.h> 55 #include <sys/stat.h> 56 #include <sys/ioctl.h> 57 #include <sys/mtio.h> 58 #include <sys/time.h> 59 60 #include <ctype.h> 61 #include <err.h> 62 #include <errno.h> 63 #include <fcntl.h> 64 #include <signal.h> 65 #include <stdio.h> 66 #include <stdlib.h> 67 #include <string.h> 68 #include <unistd.h> 69 70 #include "dd.h" 71 #include "extern.h" 72 73 static void dd_close(void); 74 static void dd_in(void); 75 static void getfdtype(IO *); 76 static void setup(void); 77 78 int main(int, char *[]); 79 80 IO in, out; /* input/output state */ 81 STAT st; /* statistics */ 82 void (*cfunc)(void); /* conversion function */ 83 uint64_t cpy_cnt; /* # of blocks to copy */ 84 u_int ddflags; /* conversion options */ 85 uint64_t cbsz; /* conversion block size */ 86 u_int files_cnt = 1; /* # of files to copy */ 87 int progress = 0; /* display sign of life */ 88 const u_char *ctab; /* conversion table */ 89 sigset_t infoset; /* a set blocking SIGINFO */ 90 91 int 92 main(int argc, char *argv[]) 93 { 94 int ch; 95 96 while ((ch = getopt(argc, argv, "")) != -1) { 97 switch (ch) { 98 default: 99 errx(EXIT_FAILURE, "usage: dd [operand ...]"); 100 /* NOTREACHED */ 101 } 102 } 103 argc -= (optind - 1); 104 argv += (optind - 1); 105 106 jcl(argv); 107 setup(); 108 109 (void)signal(SIGINFO, summaryx); 110 (void)signal(SIGINT, terminate); 111 (void)sigemptyset(&infoset); 112 (void)sigaddset(&infoset, SIGINFO); 113 114 (void)atexit(summary); 115 116 while (files_cnt--) 117 dd_in(); 118 119 dd_close(); 120 exit(0); 121 /* NOTREACHED */ 122 } 123 124 static void 125 setup(void) 126 { 127 128 if (in.name == NULL) { 129 in.name = "stdin"; 130 in.fd = STDIN_FILENO; 131 } else { 132 in.fd = open(in.name, O_RDONLY, 0); 133 if (in.fd < 0) 134 err(1, "%s", in.name); 135 } 136 137 getfdtype(&in); 138 139 if (files_cnt > 1 && !(in.flags & ISTAPE)) 140 errx(1, "files is not supported for non-tape devices"); 141 142 if (out.name == NULL) { 143 /* No way to check for read access here. */ 144 out.fd = STDOUT_FILENO; 145 out.name = "stdout"; 146 } else { 147 #define OFLAGS \ 148 (O_CREAT | (ddflags & (C_SEEK | C_NOTRUNC) ? 0 : O_TRUNC)) 149 out.fd = open(out.name, O_RDWR | OFLAGS, DEFFILEMODE); 150 /* 151 * May not have read access, so try again with write only. 152 * Without read we may have a problem if output also does 153 * not support seeks. 154 */ 155 if (out.fd < 0) { 156 out.fd = open(out.name, O_WRONLY | OFLAGS, DEFFILEMODE); 157 out.flags |= NOREAD; 158 } 159 if (out.fd < 0) 160 err(1, "%s", out.name); 161 } 162 163 getfdtype(&out); 164 165 /* 166 * Allocate space for the input and output buffers. If not doing 167 * record oriented I/O, only need a single buffer. 168 */ 169 if (!(ddflags & (C_BLOCK|C_UNBLOCK))) { 170 if ((in.db = malloc(out.dbsz + in.dbsz - 1)) == NULL) 171 err(1, NULL); 172 out.db = in.db; 173 } else if ((in.db = 174 malloc((u_int)(MAX(in.dbsz, cbsz) + cbsz))) == NULL || 175 (out.db = malloc((u_int)(out.dbsz + cbsz))) == NULL) 176 err(1, NULL); 177 in.dbp = in.db; 178 out.dbp = out.db; 179 180 /* Position the input/output streams. */ 181 if (in.offset) 182 pos_in(); 183 if (out.offset) 184 pos_out(); 185 186 /* 187 * Truncate the output file; ignore errors because it fails on some 188 * kinds of output files, tapes, for example. 189 */ 190 if ((ddflags & (C_OF | C_SEEK | C_NOTRUNC)) == (C_OF | C_SEEK)) 191 (void)ftruncate(out.fd, (off_t)out.offset * out.dbsz); 192 193 /* 194 * If converting case at the same time as another conversion, build a 195 * table that does both at once. If just converting case, use the 196 * built-in tables. 197 */ 198 if (ddflags & (C_LCASE|C_UCASE)) { 199 #ifdef NO_CONV 200 /* Should not get here, but just in case... */ 201 errx(1, "case conv and -DNO_CONV"); 202 #else /* NO_CONV */ 203 u_int cnt; 204 205 if (ddflags & C_ASCII || ddflags & C_EBCDIC) { 206 if (ddflags & C_LCASE) { 207 for (cnt = 0; cnt < 0377; ++cnt) 208 casetab[cnt] = tolower(ctab[cnt]); 209 } else { 210 for (cnt = 0; cnt < 0377; ++cnt) 211 casetab[cnt] = toupper(ctab[cnt]); 212 } 213 } else { 214 if (ddflags & C_LCASE) { 215 for (cnt = 0; cnt < 0377; ++cnt) 216 casetab[cnt] = tolower(cnt); 217 } else { 218 for (cnt = 0; cnt < 0377; ++cnt) 219 casetab[cnt] = toupper(cnt); 220 } 221 } 222 223 ctab = casetab; 224 #endif /* NO_CONV */ 225 } 226 227 (void)gettimeofday(&st.start, NULL); /* Statistics timestamp. */ 228 } 229 230 static void 231 getfdtype(IO *io) 232 { 233 struct mtget mt; 234 struct stat sb; 235 236 if (fstat(io->fd, &sb)) 237 err(1, "%s", io->name); 238 if (S_ISCHR(sb.st_mode)) 239 io->flags |= ioctl(io->fd, MTIOCGET, &mt) ? ISCHR : ISTAPE; 240 else if (lseek(io->fd, (off_t)0, SEEK_CUR) == -1 && errno == ESPIPE) 241 io->flags |= ISPIPE; /* XXX fixed in 4.4BSD */ 242 } 243 244 static void 245 dd_in(void) 246 { 247 int flags; 248 int64_t n; 249 250 for (flags = ddflags;;) { 251 if (cpy_cnt && (st.in_full + st.in_part) >= cpy_cnt) 252 return; 253 254 /* 255 * Clear the buffer first if doing "sync" on input. 256 * If doing block operations use spaces. This will 257 * affect not only the C_NOERROR case, but also the 258 * last partial input block which should be padded 259 * with zero and not garbage. 260 */ 261 if (flags & C_SYNC) { 262 if (flags & (C_BLOCK|C_UNBLOCK)) 263 (void)memset(in.dbp, ' ', in.dbsz); 264 else 265 (void)memset(in.dbp, 0, in.dbsz); 266 } 267 268 n = read(in.fd, in.dbp, in.dbsz); 269 if (n == 0) { 270 in.dbrcnt = 0; 271 return; 272 } 273 274 /* Read error. */ 275 if (n < 0) { 276 /* 277 * If noerror not specified, die. POSIX requires that 278 * the warning message be followed by an I/O display. 279 */ 280 if (!(flags & C_NOERROR)) 281 err(1, "%s", in.name); 282 warn("%s", in.name); 283 summary(); 284 285 /* 286 * If it's not a tape drive or a pipe, seek past the 287 * error. If your OS doesn't do the right thing for 288 * raw disks this section should be modified to re-read 289 * in sector size chunks. 290 */ 291 if (!(in.flags & (ISPIPE|ISTAPE)) && 292 lseek(in.fd, (off_t)in.dbsz, SEEK_CUR)) 293 warn("%s", in.name); 294 295 /* If sync not specified, omit block and continue. */ 296 if (!(ddflags & C_SYNC)) 297 continue; 298 299 /* Read errors count as full blocks. */ 300 in.dbcnt += in.dbrcnt = in.dbsz; 301 ++st.in_full; 302 303 /* Handle full input blocks. */ 304 } else if (n == in.dbsz) { 305 in.dbcnt += in.dbrcnt = n; 306 ++st.in_full; 307 308 /* Handle partial input blocks. */ 309 } else { 310 /* If sync, use the entire block. */ 311 if (ddflags & C_SYNC) 312 in.dbcnt += in.dbrcnt = in.dbsz; 313 else 314 in.dbcnt += in.dbrcnt = n; 315 ++st.in_part; 316 } 317 318 /* 319 * POSIX states that if bs is set and no other conversions 320 * than noerror, notrunc or sync are specified, the block 321 * is output without buffering as it is read. 322 */ 323 if (ddflags & C_BS) { 324 out.dbcnt = in.dbcnt; 325 dd_out(1); 326 in.dbcnt = 0; 327 continue; 328 } 329 330 if (ddflags & C_SWAB) { 331 if ((n = in.dbrcnt) & 1) { 332 ++st.swab; 333 --n; 334 } 335 swab(in.dbp, in.dbp, n); 336 } 337 338 in.dbp += in.dbrcnt; 339 (*cfunc)(); 340 } 341 } 342 343 /* 344 * Cleanup any remaining I/O and flush output. If necesssary, output file 345 * is truncated. 346 */ 347 static void 348 dd_close(void) 349 { 350 351 if (cfunc == def) 352 def_close(); 353 else if (cfunc == block) 354 block_close(); 355 else if (cfunc == unblock) 356 unblock_close(); 357 if (ddflags & C_OSYNC && out.dbcnt < out.dbsz) { 358 (void)memset(out.dbp, 0, out.dbsz - out.dbcnt); 359 out.dbcnt = out.dbsz; 360 } 361 if (out.dbcnt) 362 dd_out(1); 363 364 /* 365 * Reporting nfs write error may be defered until next 366 * write(2) or close(2) system call. So, we need to do an 367 * extra check. If an output is stdout, the file structure 368 * may be shared among with other processes and close(2) just 369 * decreases the reference count. 370 */ 371 if (out.fd == STDOUT_FILENO && fsync(out.fd) == -1 && errno != EINVAL) 372 err(1, "fsync stdout"); 373 if (close(out.fd) == -1) 374 err(1, "close"); 375 } 376 377 void 378 dd_out(int force) 379 { 380 static int warned; 381 int64_t cnt, n, nw; 382 u_char *outp; 383 384 /* 385 * Write one or more blocks out. The common case is writing a full 386 * output block in a single write; increment the full block stats. 387 * Otherwise, we're into partial block writes. If a partial write, 388 * and it's a character device, just warn. If a tape device, quit. 389 * 390 * The partial writes represent two cases. 1: Where the input block 391 * was less than expected so the output block was less than expected. 392 * 2: Where the input block was the right size but we were forced to 393 * write the block in multiple chunks. The original versions of dd(1) 394 * never wrote a block in more than a single write, so the latter case 395 * never happened. 396 * 397 * One special case is if we're forced to do the write -- in that case 398 * we play games with the buffer size, and it's usually a partial write. 399 */ 400 outp = out.db; 401 for (n = force ? out.dbcnt : out.dbsz;; n = out.dbsz) { 402 for (cnt = n;; cnt -= nw) { 403 nw = bwrite(out.fd, outp, cnt); 404 if (nw <= 0) { 405 if (nw == 0) 406 errx(1, "%s: end of device", out.name); 407 if (errno != EINTR) 408 err(1, "%s", out.name); 409 nw = 0; 410 } 411 outp += nw; 412 st.bytes += nw; 413 if (nw == n) { 414 if (n != out.dbsz) 415 ++st.out_part; 416 else 417 ++st.out_full; 418 break; 419 } 420 ++st.out_part; 421 if (nw == cnt) 422 break; 423 if (out.flags & ISCHR && !warned) { 424 warned = 1; 425 warnx("%s: short write on character device", 426 out.name); 427 } 428 if (out.flags & ISTAPE) 429 errx(1, "%s: short write on tape device", 430 out.name); 431 } 432 if ((out.dbcnt -= n) < out.dbsz) 433 break; 434 } 435 436 /* Reassemble the output block. */ 437 if (out.dbcnt) 438 (void)memmove(out.db, out.dbp - out.dbcnt, out.dbcnt); 439 out.dbp = out.db + out.dbcnt; 440 441 if (progress) 442 (void)write(STDERR_FILENO, ".", 1); 443 } 444 445 /* 446 * A protected against SIGINFO write 447 */ 448 ssize_t 449 bwrite(int fd, const void *buf, size_t len) 450 { 451 sigset_t oset; 452 ssize_t rv; 453 int oerrno; 454 455 (void)sigprocmask(SIG_BLOCK, &infoset, &oset); 456 rv = write(fd, buf, len); 457 oerrno = errno; 458 (void)sigprocmask(SIG_SETMASK, &oset, NULL); 459 errno = oerrno; 460 return (rv); 461 } 462