1 /* $NetBSD: dd.c,v 1.20 2001/04/28 22:47:23 ross 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 1.20 2001/04/28 22:47:23 ross 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 __P((void)); 74 static void dd_in __P((void)); 75 static void getfdtype __P((IO *)); 76 static void setup __P((void)); 77 78 int main __P((int, char *[])); 79 80 IO in, out; /* input/output state */ 81 STAT st; /* statistics */ 82 void (*cfunc) __P((void)); /* conversion function */ 83 u_long cpy_cnt; /* # of blocks to copy */ 84 u_int ddflags; /* conversion options */ 85 u_int 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(argc, argv) 93 int argc; 94 char *argv[]; 95 { 96 int ch; 97 98 while ((ch = getopt(argc, argv, "")) != -1) { 99 switch (ch) { 100 default: 101 errx(EXIT_FAILURE, "usage: dd [operand ...]"); 102 /* NOTREACHED */ 103 } 104 } 105 argc -= (optind - 1); 106 argv += (optind - 1); 107 108 jcl(argv); 109 setup(); 110 111 (void)signal(SIGINFO, summaryx); 112 (void)signal(SIGINT, terminate); 113 (void)sigemptyset(&infoset); 114 (void)sigaddset(&infoset, SIGINFO); 115 116 (void)atexit(summary); 117 118 while (files_cnt--) 119 dd_in(); 120 121 dd_close(); 122 exit(0); 123 /* NOTREACHED */ 124 } 125 126 static void 127 setup() 128 { 129 u_int cnt; 130 131 if (in.name == NULL) { 132 in.name = "stdin"; 133 in.fd = STDIN_FILENO; 134 } else { 135 in.fd = open(in.name, O_RDONLY, 0); 136 if (in.fd < 0) 137 err(1, "%s", in.name); 138 } 139 140 getfdtype(&in); 141 142 if (files_cnt > 1 && !(in.flags & ISTAPE)) 143 errx(1, "files is not supported for non-tape devices"); 144 145 if (out.name == NULL) { 146 /* No way to check for read access here. */ 147 out.fd = STDOUT_FILENO; 148 out.name = "stdout"; 149 } else { 150 #define OFLAGS \ 151 (O_CREAT | (ddflags & (C_SEEK | C_NOTRUNC) ? 0 : O_TRUNC)) 152 out.fd = open(out.name, O_RDWR | OFLAGS, DEFFILEMODE); 153 /* 154 * May not have read access, so try again with write only. 155 * Without read we may have a problem if output also does 156 * not support seeks. 157 */ 158 if (out.fd < 0) { 159 out.fd = open(out.name, O_WRONLY | OFLAGS, DEFFILEMODE); 160 out.flags |= NOREAD; 161 } 162 if (out.fd < 0) 163 err(1, "%s", out.name); 164 } 165 166 getfdtype(&out); 167 168 /* 169 * Allocate space for the input and output buffers. If not doing 170 * record oriented I/O, only need a single buffer. 171 */ 172 if (!(ddflags & (C_BLOCK|C_UNBLOCK))) { 173 if ((in.db = malloc(out.dbsz + in.dbsz - 1)) == NULL) 174 err(1, NULL); 175 out.db = in.db; 176 } else if ((in.db = 177 malloc((u_int)(MAX(in.dbsz, cbsz) + cbsz))) == NULL || 178 (out.db = malloc((u_int)(out.dbsz + cbsz))) == NULL) 179 err(1, NULL); 180 in.dbp = in.db; 181 out.dbp = out.db; 182 183 /* Position the input/output streams. */ 184 if (in.offset) 185 pos_in(); 186 if (out.offset) 187 pos_out(); 188 189 /* 190 * Truncate the output file; ignore errors because it fails on some 191 * kinds of output files, tapes, for example. 192 */ 193 if ((ddflags & (C_OF | C_SEEK | C_NOTRUNC)) == (C_OF | C_SEEK)) 194 (void)ftruncate(out.fd, (off_t)out.offset * out.dbsz); 195 196 /* 197 * If converting case at the same time as another conversion, build a 198 * table that does both at once. If just converting case, use the 199 * built-in tables. 200 */ 201 if (ddflags & (C_LCASE|C_UCASE)) { 202 #ifdef NO_CONV 203 /* Should not get here, but just in case... */ 204 errx(1, "case conv and -DNO_CONV"); 205 #else /* NO_CONV */ 206 if (ddflags & C_ASCII || ddflags & C_EBCDIC) { 207 if (ddflags & C_LCASE) { 208 for (cnt = 0; cnt < 0377; ++cnt) 209 casetab[cnt] = tolower(ctab[cnt]); 210 } else { 211 for (cnt = 0; cnt < 0377; ++cnt) 212 casetab[cnt] = toupper(ctab[cnt]); 213 } 214 } else { 215 if (ddflags & C_LCASE) { 216 for (cnt = 0; cnt < 0377; ++cnt) 217 casetab[cnt] = tolower(cnt); 218 } else { 219 for (cnt = 0; cnt < 0377; ++cnt) 220 casetab[cnt] = toupper(cnt); 221 } 222 } 223 224 ctab = casetab; 225 #endif /* NO_CONV */ 226 } 227 228 (void)gettimeofday(&st.start, NULL); /* Statistics timestamp. */ 229 } 230 231 static void 232 getfdtype(io) 233 IO *io; 234 { 235 struct mtget mt; 236 struct stat sb; 237 238 if (fstat(io->fd, &sb)) 239 err(1, "%s", io->name); 240 if (S_ISCHR(sb.st_mode)) 241 io->flags |= ioctl(io->fd, MTIOCGET, &mt) ? ISCHR : ISTAPE; 242 else if (lseek(io->fd, (off_t)0, SEEK_CUR) == -1 && errno == ESPIPE) 243 io->flags |= ISPIPE; /* XXX fixed in 4.4BSD */ 244 } 245 246 static void 247 dd_in() 248 { 249 int flags, n; 250 251 for (flags = ddflags;;) { 252 if (cpy_cnt && (st.in_full + st.in_part) >= cpy_cnt) 253 return; 254 255 /* 256 * Clear the buffer first if doing "sync" on input. 257 * If doing block operations use spaces. This will 258 * affect not only the C_NOERROR case, but also the 259 * last partial input block which should be padded 260 * with zero and not garbage. 261 */ 262 if (flags & C_SYNC) { 263 if (flags & (C_BLOCK|C_UNBLOCK)) 264 (void)memset(in.dbp, ' ', in.dbsz); 265 else 266 (void)memset(in.dbp, 0, in.dbsz); 267 } 268 269 n = read(in.fd, in.dbp, in.dbsz); 270 if (n == 0) { 271 in.dbrcnt = 0; 272 return; 273 } 274 275 /* Read error. */ 276 if (n < 0) { 277 /* 278 * If noerror not specified, die. POSIX requires that 279 * the warning message be followed by an I/O display. 280 */ 281 if (!(flags & C_NOERROR)) 282 err(1, "%s", in.name); 283 warn("%s", in.name); 284 summary(); 285 286 /* 287 * If it's not a tape drive or a pipe, seek past the 288 * error. If your OS doesn't do the right thing for 289 * raw disks this section should be modified to re-read 290 * in sector size chunks. 291 */ 292 if (!(in.flags & (ISPIPE|ISTAPE)) && 293 lseek(in.fd, (off_t)in.dbsz, SEEK_CUR)) 294 warn("%s", in.name); 295 296 /* If sync not specified, omit block and continue. */ 297 if (!(ddflags & C_SYNC)) 298 continue; 299 300 /* Read errors count as full blocks. */ 301 in.dbcnt += in.dbrcnt = in.dbsz; 302 ++st.in_full; 303 304 /* Handle full input blocks. */ 305 } else if (n == in.dbsz) { 306 in.dbcnt += in.dbrcnt = n; 307 ++st.in_full; 308 309 /* Handle partial input blocks. */ 310 } else { 311 /* If sync, use the entire block. */ 312 if (ddflags & C_SYNC) 313 in.dbcnt += in.dbrcnt = in.dbsz; 314 else 315 in.dbcnt += in.dbrcnt = n; 316 ++st.in_part; 317 } 318 319 /* 320 * POSIX states that if bs is set and no other conversions 321 * than noerror, notrunc or sync are specified, the block 322 * is output without buffering as it is read. 323 */ 324 if (ddflags & C_BS) { 325 out.dbcnt = in.dbcnt; 326 dd_out(1); 327 in.dbcnt = 0; 328 continue; 329 } 330 331 if (ddflags & C_SWAB) { 332 if ((n = in.dbrcnt) & 1) { 333 ++st.swab; 334 --n; 335 } 336 swab(in.dbp, in.dbp, n); 337 } 338 339 in.dbp += in.dbrcnt; 340 (*cfunc)(); 341 } 342 } 343 344 /* 345 * Cleanup any remaining I/O and flush output. If necesssary, output file 346 * is truncated. 347 */ 348 static void 349 dd_close() 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 void 366 dd_out(force) 367 int force; 368 { 369 static int warned; 370 int cnt, n, nw; 371 u_char *outp; 372 373 /* 374 * Write one or more blocks out. The common case is writing a full 375 * output block in a single write; increment the full block stats. 376 * Otherwise, we're into partial block writes. If a partial write, 377 * and it's a character device, just warn. If a tape device, quit. 378 * 379 * The partial writes represent two cases. 1: Where the input block 380 * was less than expected so the output block was less than expected. 381 * 2: Where the input block was the right size but we were forced to 382 * write the block in multiple chunks. The original versions of dd(1) 383 * never wrote a block in more than a single write, so the latter case 384 * never happened. 385 * 386 * One special case is if we're forced to do the write -- in that case 387 * we play games with the buffer size, and it's usually a partial write. 388 */ 389 outp = out.db; 390 for (n = force ? out.dbcnt : out.dbsz;; n = out.dbsz) { 391 for (cnt = n;; cnt -= nw) { 392 nw = bwrite(out.fd, outp, cnt); 393 if (nw <= 0) { 394 if (nw == 0) 395 errx(1, "%s: end of device", out.name); 396 if (errno != EINTR) 397 err(1, "%s", out.name); 398 nw = 0; 399 } 400 outp += nw; 401 st.bytes += nw; 402 if (nw == n) { 403 if (n != out.dbsz) 404 ++st.out_part; 405 else 406 ++st.out_full; 407 break; 408 } 409 ++st.out_part; 410 if (nw == cnt) 411 break; 412 if (out.flags & ISCHR && !warned) { 413 warned = 1; 414 warnx("%s: short write on character device", 415 out.name); 416 } 417 if (out.flags & ISTAPE) 418 errx(1, "%s: short write on tape device", out.name); 419 } 420 if ((out.dbcnt -= n) < out.dbsz) 421 break; 422 } 423 424 /* Reassemble the output block. */ 425 if (out.dbcnt) 426 (void)memmove(out.db, out.dbp - out.dbcnt, out.dbcnt); 427 out.dbp = out.db + out.dbcnt; 428 429 if (progress) 430 (void)write(STDERR_FILENO, ".", 1); 431 } 432 433 /* 434 * A protected against SIGINFO write 435 */ 436 ssize_t 437 bwrite(fd, buf, len) 438 int fd; 439 const void *buf; 440 size_t len; 441 { 442 sigset_t oset; 443 ssize_t rv; 444 int oerrno; 445 446 (void)sigprocmask(SIG_BLOCK, &infoset, &oset); 447 rv = write(fd, buf, len); 448 oerrno = errno; 449 (void)sigprocmask(SIG_SETMASK, &oset, NULL); 450 errno = oerrno; 451 return rv; 452 } 453