1 /* $NetBSD: dd.c,v 1.12 1998/08/19 01:32:44 thorpej 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 1.12 1998/08/19 01:32:44 thorpej 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 59 #include <ctype.h> 60 #include <err.h> 61 #include <errno.h> 62 #include <fcntl.h> 63 #include <signal.h> 64 #include <stdio.h> 65 #include <stdlib.h> 66 #include <string.h> 67 #include <time.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 const u_char *ctab; /* conversion table */ 88 89 int 90 main(argc, argv) 91 int argc; 92 char *argv[]; 93 { 94 jcl(argv); 95 setup(); 96 97 (void)signal(SIGINFO, summaryx); 98 (void)signal(SIGINT, terminate); 99 100 (void)atexit(summary); 101 102 while (files_cnt--) 103 dd_in(); 104 105 dd_close(); 106 exit(0); 107 /* NOTREACHED */ 108 } 109 110 static void 111 setup() 112 { 113 u_int cnt; 114 115 if (in.name == NULL) { 116 in.name = "stdin"; 117 in.fd = STDIN_FILENO; 118 } else { 119 in.fd = open(in.name, O_RDONLY, 0); 120 if (in.fd < 0) 121 err(1, "%s", in.name); 122 } 123 124 getfdtype(&in); 125 126 if (files_cnt > 1 && !(in.flags & ISTAPE)) 127 errx(1, "files is not supported for non-tape devices"); 128 129 if (out.name == NULL) { 130 /* No way to check for read access here. */ 131 out.fd = STDOUT_FILENO; 132 out.name = "stdout"; 133 } else { 134 #define OFLAGS \ 135 (O_CREAT | (ddflags & (C_SEEK | C_NOTRUNC) ? 0 : O_TRUNC)) 136 out.fd = open(out.name, O_RDWR | OFLAGS, DEFFILEMODE); 137 /* 138 * May not have read access, so try again with write only. 139 * Without read we may have a problem if output also does 140 * not support seeks. 141 */ 142 if (out.fd < 0) { 143 out.fd = open(out.name, O_WRONLY | OFLAGS, DEFFILEMODE); 144 out.flags |= NOREAD; 145 } 146 if (out.fd < 0) 147 err(1, "%s", out.name); 148 } 149 150 getfdtype(&out); 151 152 /* 153 * Allocate space for the input and output buffers. If not doing 154 * record oriented I/O, only need a single buffer. 155 */ 156 if (!(ddflags & (C_BLOCK|C_UNBLOCK))) { 157 if ((in.db = malloc(out.dbsz + in.dbsz - 1)) == NULL) 158 err(1, "%s", ""); 159 out.db = in.db; 160 } else if ((in.db = 161 malloc((u_int)(MAX(in.dbsz, cbsz) + cbsz))) == NULL || 162 (out.db = malloc((u_int)(out.dbsz + cbsz))) == NULL) 163 err(1, "%s", ""); 164 in.dbp = in.db; 165 out.dbp = out.db; 166 167 /* Position the input/output streams. */ 168 if (in.offset) 169 pos_in(); 170 if (out.offset) 171 pos_out(); 172 173 /* 174 * Truncate the output file; ignore errors because it fails on some 175 * kinds of output files, tapes, for example. 176 */ 177 if ((ddflags & (C_OF | C_SEEK | C_NOTRUNC)) == (C_OF | C_SEEK)) 178 (void)ftruncate(out.fd, (off_t)out.offset * out.dbsz); 179 180 /* 181 * If converting case at the same time as another conversion, build a 182 * table that does both at once. If just converting case, use the 183 * built-in tables. 184 */ 185 if (ddflags & (C_LCASE|C_UCASE)) { 186 #ifdef NO_CONV 187 /* Should not get here, but just in case... */ 188 errx(1, "case conv and -DNO_CONV"); 189 #else /* NO_CONV */ 190 if (ddflags & C_ASCII || ddflags & C_EBCDIC) { 191 if (ddflags & C_LCASE) { 192 for (cnt = 0; cnt < 0377; ++cnt) 193 casetab[cnt] = tolower(ctab[cnt]); 194 } else { 195 for (cnt = 0; cnt < 0377; ++cnt) 196 casetab[cnt] = toupper(ctab[cnt]); 197 } 198 } else { 199 if (ddflags & C_LCASE) { 200 for (cnt = 0; cnt < 0377; ++cnt) 201 casetab[cnt] = tolower(cnt); 202 } else { 203 for (cnt = 0; cnt < 0377; ++cnt) 204 casetab[cnt] = toupper(cnt); 205 } 206 } 207 208 ctab = casetab; 209 #endif /* NO_CONV */ 210 } 211 212 (void)time(&st.start); /* Statistics timestamp. */ 213 } 214 215 static void 216 getfdtype(io) 217 IO *io; 218 { 219 struct mtget mt; 220 struct stat sb; 221 222 if (fstat(io->fd, &sb)) 223 err(1, "%s", io->name); 224 if (S_ISCHR(sb.st_mode)) 225 io->flags |= ioctl(io->fd, MTIOCGET, &mt) ? ISCHR : ISTAPE; 226 else if (lseek(io->fd, (off_t)0, SEEK_CUR) == -1 && errno == ESPIPE) 227 io->flags |= ISPIPE; /* XXX fixed in 4.4BSD */ 228 } 229 230 static void 231 dd_in() 232 { 233 int flags, n; 234 235 for (flags = ddflags;;) { 236 if (cpy_cnt && (st.in_full + st.in_part) >= cpy_cnt) 237 return; 238 239 /* 240 * Clear the buffer first if doing "sync" on input. 241 * If doing block operations use spaces. This will 242 * affect not only the C_NOERROR case, but also the 243 * last partial input block which should be padded 244 * with zero and not garbage. 245 */ 246 if (flags & C_SYNC) { 247 if (flags & (C_BLOCK|C_UNBLOCK)) 248 (void)memset(in.dbp, ' ', in.dbsz); 249 else 250 (void)memset(in.dbp, 0, in.dbsz); 251 } 252 253 n = read(in.fd, in.dbp, in.dbsz); 254 if (n == 0) { 255 in.dbrcnt = 0; 256 return; 257 } 258 259 /* Read error. */ 260 if (n < 0) { 261 /* 262 * If noerror not specified, die. POSIX requires that 263 * the warning message be followed by an I/O display. 264 */ 265 if (!(flags & C_NOERROR)) 266 err(1, "%s", in.name); 267 warn("%s", in.name); 268 summary(); 269 270 /* 271 * If it's not a tape drive or a pipe, seek past the 272 * error. If your OS doesn't do the right thing for 273 * raw disks this section should be modified to re-read 274 * in sector size chunks. 275 */ 276 if (!(in.flags & (ISPIPE|ISTAPE)) && 277 lseek(in.fd, (off_t)in.dbsz, SEEK_CUR)) 278 warn("%s", in.name); 279 280 /* If sync not specified, omit block and continue. */ 281 if (!(ddflags & C_SYNC)) 282 continue; 283 284 /* Read errors count as full blocks. */ 285 in.dbcnt += in.dbrcnt = in.dbsz; 286 ++st.in_full; 287 288 /* Handle full input blocks. */ 289 } else if (n == in.dbsz) { 290 in.dbcnt += in.dbrcnt = n; 291 ++st.in_full; 292 293 /* Handle partial input blocks. */ 294 } else { 295 /* If sync, use the entire block. */ 296 if (ddflags & C_SYNC) 297 in.dbcnt += in.dbrcnt = in.dbsz; 298 else 299 in.dbcnt += in.dbrcnt = n; 300 ++st.in_part; 301 } 302 303 /* 304 * POSIX states that if bs is set and no other conversions 305 * than noerror, notrunc or sync are specified, the block 306 * is output without buffering as it is read. 307 */ 308 if (ddflags & C_BS) { 309 out.dbcnt = in.dbcnt; 310 dd_out(1); 311 in.dbcnt = 0; 312 continue; 313 } 314 315 if (ddflags & C_SWAB) { 316 if ((n = in.dbcnt) & 1) { 317 ++st.swab; 318 --n; 319 } 320 swab(in.dbp, in.dbp, n); 321 } 322 323 in.dbp += in.dbrcnt; 324 (*cfunc)(); 325 } 326 } 327 328 /* 329 * Cleanup any remaining I/O and flush output. If necesssary, output file 330 * is truncated. 331 */ 332 static void 333 dd_close() 334 { 335 if (cfunc == def) 336 def_close(); 337 else if (cfunc == block) 338 block_close(); 339 else if (cfunc == unblock) 340 unblock_close(); 341 if (ddflags & C_OSYNC && out.dbcnt < out.dbsz) { 342 (void)memset(out.dbp, 0, out.dbsz - out.dbcnt); 343 out.dbcnt = out.dbsz; 344 } 345 if (out.dbcnt) 346 dd_out(1); 347 } 348 349 void 350 dd_out(force) 351 int force; 352 { 353 static int warned; 354 int cnt, n, nw; 355 u_char *outp; 356 357 /* 358 * Write one or more blocks out. The common case is writing a full 359 * output block in a single write; increment the full block stats. 360 * Otherwise, we're into partial block writes. If a partial write, 361 * and it's a character device, just warn. If a tape device, quit. 362 * 363 * The partial writes represent two cases. 1: Where the input block 364 * was less than expected so the output block was less than expected. 365 * 2: Where the input block was the right size but we were forced to 366 * write the block in multiple chunks. The original versions of dd(1) 367 * never wrote a block in more than a single write, so the latter case 368 * never happened. 369 * 370 * One special case is if we're forced to do the write -- in that case 371 * we play games with the buffer size, and it's usually a partial write. 372 */ 373 outp = out.db; 374 for (n = force ? out.dbcnt : out.dbsz;; n = out.dbsz) { 375 for (cnt = n;; cnt -= nw) { 376 nw = write(out.fd, outp, cnt); 377 if (nw <= 0) { 378 if (nw == 0) 379 errx(1, "%s: end of device", out.name); 380 if (errno != EINTR) 381 err(1, "%s", out.name); 382 nw = 0; 383 } 384 outp += nw; 385 st.bytes += nw; 386 if (nw == n) { 387 if (n != out.dbsz) 388 ++st.out_part; 389 else 390 ++st.out_full; 391 break; 392 } 393 ++st.out_part; 394 if (nw == cnt) 395 break; 396 if (out.flags & ISCHR && !warned) { 397 warned = 1; 398 warnx("%s: short write on character device", 399 out.name); 400 } 401 if (out.flags & ISTAPE) 402 errx(1, "%s: short write on tape device", out.name); 403 } 404 if ((out.dbcnt -= n) < out.dbsz) 405 break; 406 } 407 408 /* Reassemble the output block. */ 409 if (out.dbcnt) 410 (void)memmove(out.db, out.dbp - out.dbcnt, out.dbcnt); 411 out.dbp = out.db + out.dbcnt; 412 } 413