1 /*- 2 * Copyright (c) 1991, 1993, 1994 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Keith Muller of the University of California, San Diego and Lance 7 * Visser of Convex Computer Corporation. 8 * 9 * %sccs.include.redist.c% 10 */ 11 12 #ifndef lint 13 static char copyright[] = 14 "@(#) Copyright (c) 1991, 1993, 1994\n\ 15 The Regents of the University of California. All rights reserved.\n"; 16 #endif /* not lint */ 17 18 #ifndef lint 19 static char sccsid[] = "@(#)dd.c 8.5 (Berkeley) 04/02/94"; 20 #endif /* not lint */ 21 22 #include <sys/param.h> 23 #include <sys/stat.h> 24 #include <sys/ioctl.h> 25 #include <sys/mtio.h> 26 27 #include <ctype.h> 28 #include <err.h> 29 #include <errno.h> 30 #include <fcntl.h> 31 #include <signal.h> 32 #include <stdio.h> 33 #include <stdlib.h> 34 #include <string.h> 35 #include <unistd.h> 36 37 #include "dd.h" 38 #include "extern.h" 39 40 static void dd_close __P((void)); 41 static void dd_in __P((void)); 42 static void getfdtype __P((IO *)); 43 static void setup __P((void)); 44 45 IO in, out; /* input/output state */ 46 STAT st; /* statistics */ 47 void (*cfunc) __P((void)); /* conversion function */ 48 u_long cpy_cnt; /* # of blocks to copy */ 49 u_int ddflags; /* conversion options */ 50 u_int cbsz; /* conversion block size */ 51 u_int files_cnt = 1; /* # of files to copy */ 52 u_char *ctab; /* conversion table */ 53 54 int 55 main(argc, argv) 56 int argc; 57 char *argv[]; 58 { 59 jcl(argv); 60 setup(); 61 62 (void)signal(SIGINFO, summaryx); 63 (void)signal(SIGINT, terminate); 64 65 atexit(summary); 66 67 while (files_cnt--) 68 dd_in(); 69 70 dd_close(); 71 exit(0); 72 } 73 74 static void 75 setup() 76 { 77 u_int cnt; 78 79 if (in.name == NULL) { 80 in.name = "stdin"; 81 in.fd = STDIN_FILENO; 82 } else { 83 in.fd = open(in.name, O_RDONLY, 0); 84 if (in.fd < 0) 85 err(1, "%s", in.name); 86 } 87 88 getfdtype(&in); 89 90 if (files_cnt > 1 && !(in.flags & ISTAPE)) 91 errx(1, "files is not supported for non-tape devices"); 92 93 if (out.name == NULL) { 94 /* No way to check for read access here. */ 95 out.fd = STDOUT_FILENO; 96 out.name = "stdout"; 97 } else { 98 #define OFLAGS \ 99 (O_CREAT | (ddflags & (C_SEEK | C_NOTRUNC) ? 0 : O_TRUNC)) 100 out.fd = open(out.name, O_RDWR | OFLAGS, DEFFILEMODE); 101 /* 102 * May not have read access, so try again with write only. 103 * Without read we may have a problem if output also does 104 * not support seeks. 105 */ 106 if (out.fd < 0) { 107 out.fd = open(out.name, O_WRONLY | OFLAGS, DEFFILEMODE); 108 out.flags |= NOREAD; 109 } 110 if (out.fd < 0) 111 err(1, "%s", out.name); 112 } 113 114 getfdtype(&out); 115 116 /* 117 * Allocate space for the input and output buffers. If not doing 118 * record oriented I/O, only need a single buffer. 119 */ 120 if (!(ddflags & (C_BLOCK|C_UNBLOCK))) { 121 if ((in.db = malloc(out.dbsz + in.dbsz - 1)) == NULL) 122 err(1, NULL); 123 out.db = in.db; 124 } else if ((in.db = 125 malloc((u_int)(MAX(in.dbsz, cbsz) + cbsz))) == NULL || 126 (out.db = malloc((u_int)(out.dbsz + cbsz))) == NULL) 127 err(1, NULL); 128 in.dbp = in.db; 129 out.dbp = out.db; 130 131 /* Position the input/output streams. */ 132 if (in.offset) 133 pos_in(); 134 if (out.offset) 135 pos_out(); 136 137 /* 138 * Truncate the output file; ignore errors because it fails on some 139 * kinds of output files, tapes, for example. 140 */ 141 if (ddflags & (C_OF | C_SEEK | C_NOTRUNC) == (C_OF | C_SEEK)) 142 (void)ftruncate(out.fd, (off_t)out.offset * out.dbsz); 143 144 /* 145 * If converting case at the same time as another conversion, build a 146 * table that does both at once. If just converting case, use the 147 * built-in tables. 148 */ 149 if (ddflags & (C_LCASE|C_UCASE)) 150 if (ddflags & C_ASCII) 151 if (ddflags & C_LCASE) { 152 for (cnt = 0; cnt < 0377; ++cnt) 153 if (isupper(ctab[cnt])) 154 ctab[cnt] = tolower(ctab[cnt]); 155 } else { 156 for (cnt = 0; cnt < 0377; ++cnt) 157 if (islower(ctab[cnt])) 158 ctab[cnt] = toupper(ctab[cnt]); 159 } 160 else if (ddflags & C_EBCDIC) 161 if (ddflags & C_LCASE) { 162 for (cnt = 0; cnt < 0377; ++cnt) 163 if (isupper(cnt)) 164 ctab[cnt] = ctab[tolower(cnt)]; 165 } else { 166 for (cnt = 0; cnt < 0377; ++cnt) 167 if (islower(cnt)) 168 ctab[cnt] = ctab[toupper(cnt)]; 169 } 170 else 171 ctab = ddflags & C_LCASE ? u2l : l2u; 172 (void)time(&st.start); /* Statistics timestamp. */ 173 } 174 175 static void 176 getfdtype(io) 177 IO *io; 178 { 179 struct mtget mt; 180 struct stat sb; 181 182 if (fstat(io->fd, &sb)) 183 err(1, "%s", io->name); 184 if (S_ISCHR(sb.st_mode)) 185 io->flags |= ioctl(io->fd, MTIOCGET, &mt) ? ISCHR : ISTAPE; 186 else if (lseek(io->fd, (off_t)0, SEEK_CUR) == -1 && errno == ESPIPE) 187 io->flags |= ISPIPE; /* XXX fixed in 4.4BSD */ 188 } 189 190 static void 191 dd_in() 192 { 193 int flags, n; 194 195 for (flags = ddflags;;) { 196 if (cpy_cnt && (st.in_full + st.in_part) >= cpy_cnt) 197 return; 198 199 /* 200 * Zero the buffer first if trying to recover from errors so 201 * lose the minimum amount of data. If doing block operations 202 * use spaces. 203 */ 204 if ((flags & (C_NOERROR|C_SYNC)) == (C_NOERROR|C_SYNC)) 205 if (flags & (C_BLOCK|C_UNBLOCK)) 206 memset(in.dbp, ' ', in.dbsz); 207 else 208 memset(in.dbp, 0, in.dbsz); 209 210 n = read(in.fd, in.dbp, in.dbsz); 211 if (n == 0) { 212 in.dbrcnt = 0; 213 return; 214 } 215 216 /* Read error. */ 217 if (n < 0) { 218 /* 219 * If noerror not specified, die. POSIX requires that 220 * the warning message be followed by an I/O display. 221 */ 222 if (!(flags & C_NOERROR)) 223 err(1, "%s", in.name); 224 warn("%s", in.name); 225 summary(); 226 227 /* 228 * If it's not a tape drive or a pipe, seek past the 229 * error. If your OS doesn't do the right thing for 230 * raw disks this section should be modified to re-read 231 * in sector size chunks. 232 */ 233 if (!(in.flags & (ISPIPE|ISTAPE)) && 234 lseek(in.fd, (off_t)in.dbsz, SEEK_CUR)) 235 warn("%s", in.name); 236 237 /* If sync not specified, omit block and continue. */ 238 if (!(ddflags & C_SYNC)) 239 continue; 240 241 /* Read errors count as full blocks. */ 242 in.dbcnt += in.dbrcnt = in.dbsz; 243 ++st.in_full; 244 245 /* Handle full input blocks. */ 246 } else if (n == in.dbsz) { 247 in.dbcnt += in.dbrcnt = n; 248 ++st.in_full; 249 250 /* Handle partial input blocks. */ 251 } else { 252 /* If sync, use the entire block. */ 253 if (ddflags & C_SYNC) 254 in.dbcnt += in.dbrcnt = in.dbsz; 255 else 256 in.dbcnt += in.dbrcnt = n; 257 ++st.in_part; 258 } 259 260 /* 261 * POSIX states that if bs is set and no other conversions 262 * than noerror, notrunc or sync are specified, the block 263 * is output without buffering as it is read. 264 */ 265 if (ddflags & C_BS) { 266 out.dbcnt = in.dbcnt; 267 dd_out(1); 268 in.dbcnt = 0; 269 continue; 270 } 271 272 if (ddflags & C_SWAB) { 273 if ((n = in.dbcnt) & 1) { 274 ++st.swab; 275 --n; 276 } 277 swab(in.dbp, in.dbp, n); 278 } 279 280 in.dbp += in.dbrcnt; 281 (*cfunc)(); 282 } 283 } 284 285 /* 286 * Cleanup any remaining I/O and flush output. If necesssary, output file 287 * is truncated. 288 */ 289 static void 290 dd_close() 291 { 292 if (cfunc == def) 293 def_close(); 294 else if (cfunc == block) 295 block_close(); 296 else if (cfunc == unblock) 297 unblock_close(); 298 if (ddflags & C_OSYNC && out.dbcnt < out.dbsz) { 299 memset(out.dbp, 0, out.dbsz - out.dbcnt); 300 out.dbcnt = out.dbsz; 301 } 302 if (out.dbcnt) 303 dd_out(1); 304 } 305 306 void 307 dd_out(force) 308 int force; 309 { 310 static int warned; 311 int cnt, n, nw; 312 u_char *outp; 313 314 /* 315 * Write one or more blocks out. The common case is writing a full 316 * output block in a single write; increment the full block stats. 317 * Otherwise, we're into partial block writes. If a partial write, 318 * and it's a character device, just warn. If a tape device, quit. 319 * 320 * The partial writes represent two cases. 1: Where the input block 321 * was less than expected so the output block was less than expected. 322 * 2: Where the input block was the right size but we were forced to 323 * write the block in multiple chunks. The original versions of dd(1) 324 * never wrote a block in more than a single write, so the latter case 325 * never happened. 326 * 327 * One special case is if we're forced to do the write -- in that case 328 * we play games with the buffer size, and it's usually a partial write. 329 */ 330 outp = out.db; 331 for (n = force ? out.dbcnt : out.dbsz;; n = out.dbsz) { 332 for (cnt = n;; cnt -= nw) { 333 nw = write(out.fd, outp, cnt); 334 if (nw <= 0) { 335 if (nw == 0) 336 errx(1, "%s: end of device", out.name); 337 if (errno != EINTR) 338 err(1, "%s", out.name); 339 nw = 0; 340 } 341 outp += nw; 342 st.bytes += nw; 343 if (nw == n) { 344 if (n != out.dbsz) 345 ++st.out_part; 346 else 347 ++st.out_full; 348 break; 349 } 350 ++st.out_part; 351 if (nw == cnt) 352 break; 353 if (out.flags & ISCHR && !warned) { 354 warned = 1; 355 warnx("%s: short write on character device", 356 out.name); 357 } 358 if (out.flags & ISTAPE) 359 errx(1, "%s: short write on tape device", out.name); 360 } 361 if ((out.dbcnt -= n) < out.dbsz) 362 break; 363 } 364 365 /* Reassemble the output block. */ 366 if (out.dbcnt) 367 memmove(out.db, out.dbp - out.dbcnt, out.dbcnt); 368 out.dbp = out.db + out.dbcnt; 369 } 370