1 /*- 2 * Copyright (c) 1991, 1993 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\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 8.2 (Berkeley) 01/13/94"; 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 <errno.h> 29 #include <fcntl.h> 30 #include <signal.h> 31 #include <stdio.h> 32 #include <stdlib.h> 33 #include <string.h> 34 #include <unistd.h> 35 36 #include "dd.h" 37 #include "extern.h" 38 39 static void dd_close __P((void)); 40 static void dd_in __P((void)); 41 static void setup __P((void)); 42 43 IO in, out; /* input/output state */ 44 STAT st; /* statistics */ 45 void (*cfunc) __P((void)); /* conversion function */ 46 u_long cpy_cnt; /* # of blocks to copy */ 47 u_int ddflags; /* conversion options */ 48 u_int cbsz; /* conversion block size */ 49 u_int files_cnt = 1; /* # of files to copy */ 50 int errstats; /* show statistics on error */ 51 u_char *ctab; /* conversion table */ 52 53 int 54 main(argc, argv) 55 int argc; 56 char *argv[]; 57 { 58 jcl(argv); 59 setup(); 60 61 (void)signal(SIGINFO, summary); 62 (void)signal(SIGINT, terminate); 63 64 for (errstats = 1; files_cnt--;) 65 dd_in(); 66 67 dd_close(); 68 summary(0); 69 exit(0); 70 } 71 72 static void 73 setup() 74 { 75 register u_int cnt; 76 struct stat sb; 77 struct mtget mt; 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("%s: %s", in.name, strerror(errno)); 86 } 87 88 if (fstat(in.fd, &sb)) 89 err("%s: %s", in.name, strerror(errno)); 90 if (S_ISCHR(sb.st_mode)) 91 in.flags |= ioctl(in.fd, MTIOCGET, &mt) ? ISCHR : ISTAPE; 92 else if (lseek(in.fd, (off_t)0, SEEK_CUR) == -1 && errno == ESPIPE) 93 in.flags |= ISPIPE; /* XXX fixed in 4.4BSD */ 94 95 if (files_cnt > 1 && !(in.flags & ISTAPE)) 96 err("files is not supported for non-tape devices"); 97 98 if (out.name == NULL) { 99 /* No way to check for read access here. */ 100 out.fd = STDOUT_FILENO; 101 out.name = "stdout"; 102 } else { 103 #define OFLAGS \ 104 (O_CREAT | (ddflags & (C_SEEK | C_NOTRUNC) ? 0 : O_TRUNC)) 105 out.fd = open(out.name, O_RDWR | OFLAGS, DEFFILEMODE); 106 /* 107 * May not have read access, so try again with write only. 108 * Without read we may have a problem if output also does 109 * not support seeks. 110 */ 111 if (out.fd < 0) { 112 out.fd = open(out.name, O_WRONLY | OFLAGS, DEFFILEMODE); 113 out.flags |= NOREAD; 114 } 115 if (out.fd < 0) 116 err("%s: %s", out.name, strerror(errno)); 117 } 118 119 if (fstat(out.fd, &sb)) 120 err("%s: %s", out.name, strerror(errno)); 121 if (S_ISCHR(sb.st_mode)) 122 out.flags |= ioctl(out.fd, MTIOCGET, &mt) ? ISCHR : ISTAPE; 123 else if (lseek(out.fd, (off_t)0, SEEK_CUR) == -1 && errno == ESPIPE) 124 out.flags |= ISPIPE; /* XXX fixed in 4.4BSD */ 125 126 /* 127 * Allocate space for the input and output buffers. If not doing 128 * record oriented I/O, only need a single buffer. 129 */ 130 if (!(ddflags & (C_BLOCK|C_UNBLOCK))) { 131 if ((in.db = malloc(out.dbsz + in.dbsz - 1)) == NULL) 132 err("%s", strerror(errno)); 133 out.db = in.db; 134 } else if ((in.db = 135 malloc((u_int)(MAX(in.dbsz, cbsz) + cbsz))) == NULL || 136 (out.db = malloc((u_int)(out.dbsz + cbsz))) == NULL) 137 err("%s", strerror(errno)); 138 in.dbp = in.db; 139 out.dbp = out.db; 140 141 /* Position the input/output streams. */ 142 if (in.offset) 143 pos_in(); 144 if (out.offset) 145 pos_out(); 146 147 /* 148 * Truncate the output file; ignore errors because it fails on some 149 * kinds of output files, tapes, for example. 150 */ 151 if (ddflags & (C_OF | C_SEEK | C_NOTRUNC) == (C_OF | C_SEEK)) 152 (void)ftruncate(out.fd, (off_t)out.offset * out.dbsz); 153 154 /* 155 * If converting case at the same time as another conversion, build a 156 * table that does both at once. If just converting case, use the 157 * built-in tables. 158 */ 159 if (ddflags & (C_LCASE|C_UCASE)) 160 if (ddflags & C_ASCII) 161 if (ddflags & C_LCASE) { 162 for (cnt = 0; cnt < 0377; ++cnt) 163 if (isupper(ctab[cnt])) 164 ctab[cnt] = tolower(ctab[cnt]); 165 } else { 166 for (cnt = 0; cnt < 0377; ++cnt) 167 if (islower(ctab[cnt])) 168 ctab[cnt] = toupper(ctab[cnt]); 169 } 170 else if (ddflags & C_EBCDIC) 171 if (ddflags & C_LCASE) { 172 for (cnt = 0; cnt < 0377; ++cnt) 173 if (isupper(cnt)) 174 ctab[cnt] = ctab[tolower(cnt)]; 175 } else { 176 for (cnt = 0; cnt < 0377; ++cnt) 177 if (islower(cnt)) 178 ctab[cnt] = ctab[toupper(cnt)]; 179 } 180 else 181 ctab = ddflags & C_LCASE ? u2l : l2u; 182 (void)time(&st.start); /* Statistics timestamp. */ 183 } 184 185 static void 186 dd_in() 187 { 188 register int flags, n; 189 190 for (flags = ddflags;;) { 191 if (cpy_cnt && (st.in_full + st.in_part) >= cpy_cnt) 192 return; 193 194 /* 195 * Zero the buffer first if trying to recover from errors so 196 * lose the minimum amount of data. If doing block operations 197 * use spaces. 198 */ 199 if ((flags & (C_NOERROR|C_SYNC)) == (C_NOERROR|C_SYNC)) 200 if (flags & (C_BLOCK|C_UNBLOCK)) 201 memset(in.dbp, ' ', in.dbsz); 202 else 203 memset(in.dbp, 0, in.dbsz); 204 205 n = read(in.fd, in.dbp, in.dbsz); 206 if (n == 0) { 207 in.dbrcnt = 0; 208 return; 209 } 210 211 /* Read error. */ 212 if (n < 0) { 213 /* 214 * If noerror not specified, die. POSIX requires that 215 * the warning message be followed by an I/O display. 216 */ 217 if (!(flags & C_NOERROR)) 218 err("%s: %s", in.name, strerror(errno)); 219 warn("%s: %s", in.name, strerror(errno)); 220 summary(0); 221 222 /* 223 * If it's not a tape drive or a pipe, seek past the 224 * error. If your OS doesn't do the right thing for 225 * raw disks this section should be modified to re-read 226 * in sector size chunks. 227 */ 228 if (!(in.flags & (ISPIPE|ISTAPE)) && 229 lseek(in.fd, (off_t)in.dbsz, SEEK_CUR)) 230 warn("%s: %s", in.name, strerror(errno)); 231 232 /* If sync not specified, omit block and continue. */ 233 if (!(ddflags & C_SYNC)) 234 continue; 235 236 /* Read errors count as full blocks. */ 237 in.dbcnt += in.dbrcnt = in.dbsz; 238 ++st.in_full; 239 240 /* Handle full input blocks. */ 241 } else if (n == in.dbsz) { 242 in.dbcnt += in.dbrcnt = n; 243 ++st.in_full; 244 245 /* Handle partial input blocks. */ 246 } else { 247 /* If sync, use the entire block. */ 248 if (ddflags & C_SYNC) 249 in.dbcnt += in.dbrcnt = in.dbsz; 250 else 251 in.dbcnt += in.dbrcnt = n; 252 ++st.in_part; 253 } 254 255 /* 256 * POSIX states that if bs is set and no other conversions 257 * than noerror, notrunc or sync are specified, the block 258 * is output without buffering as it is read. 259 */ 260 if (ddflags & C_BS) { 261 out.dbcnt = in.dbcnt; 262 dd_out(1); 263 in.dbcnt = 0; 264 continue; 265 } 266 267 if (ddflags & C_SWAB) { 268 if ((n = in.dbcnt) & 1) { 269 ++st.swab; 270 --n; 271 } 272 swab(in.dbp, in.dbp, n); 273 } 274 275 in.dbp += in.dbrcnt; 276 (*cfunc)(); 277 } 278 } 279 280 /* 281 * Cleanup any remaining I/O and flush output. If necesssary, output file 282 * is truncated. 283 */ 284 static void 285 dd_close() 286 { 287 if (cfunc == def) 288 def_close(); 289 else if (cfunc == block) 290 block_close(); 291 else if (cfunc == unblock) 292 unblock_close(); 293 if (ddflags & C_OSYNC && out.dbcnt < out.dbsz) { 294 bzero(out.dbp, out.dbsz - out.dbcnt); 295 out.dbcnt = out.dbsz; 296 } 297 if (out.dbcnt) 298 dd_out(1); 299 } 300 301 void 302 dd_out(force) 303 int force; 304 { 305 static int warned; 306 register int cnt, n, nw; 307 register u_char *outp; 308 309 /* 310 * Write one or more blocks out. The common case is writing a full 311 * output block in a single write; increment the full block stats. 312 * Otherwise, we're into partial block writes. If a partial write, 313 * and it's a character device, just warn. If a tape device, quit. 314 * 315 * The partial writes represent two cases. 1: Where the input block 316 * was less than expected so the output block was less than expected. 317 * 2: Where the input block was the right size but we were forced to 318 * write the block in multiple chunks. The original versions of dd(1) 319 * never wrote a block in more than a single write, so the latter case 320 * never happened. 321 * 322 * One special case is if we're forced to do the write -- in that case 323 * we play games with the buffer size, and it's usually a partial write. 324 */ 325 outp = out.db; 326 for (n = force ? out.dbcnt : out.dbsz;; n = out.dbsz) { 327 for (cnt = n;; cnt -= nw) { 328 nw = write(out.fd, outp, cnt); 329 if (nw <= 0) { 330 if (nw == 0) 331 err("%s: end of device", out.name); 332 if (errno != EINTR) 333 err("%s: %s", 334 out.name, strerror(errno)); 335 nw = 0; 336 } 337 outp += nw; 338 st.bytes += nw; 339 if (nw == n) { 340 if (n != out.dbsz) 341 ++st.out_part; 342 else 343 ++st.out_full; 344 break; 345 } 346 ++st.out_part; 347 if (nw == cnt) 348 break; 349 if (out.flags & ISCHR && !warned) { 350 warned = 1; 351 warn("%s: short write on character device", 352 out.name); 353 } 354 if (out.flags & ISTAPE) 355 err("%s: short write on tape device", out.name); 356 } 357 if ((out.dbcnt -= n) < out.dbsz) 358 break; 359 } 360 361 /* Reassemble the output block. */ 362 if (out.dbcnt) 363 memmove(out.db, out.dbp - out.dbcnt, out.dbcnt); 364 out.dbp = out.db + out.dbcnt; 365 } 366