1 /*- 2 * Copyright (c) 1991 The Regents of the University of California. 3 * 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 char copyright[] = 14 "@(#) Copyright (c) 1991 The Regents of the University of California.\n\ 15 All rights reserved.\n"; 16 #endif /* not lint */ 17 18 #ifndef lint 19 static char sccsid[] = "@(#)dd.c 5.12 (Berkeley) 06/02/92"; 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 #include <signal.h> 27 #include <fcntl.h> 28 #include <unistd.h> 29 #include <errno.h> 30 #include <stdio.h> 31 #include <ctype.h> 32 #include <stdlib.h> 33 #include <string.h> 34 #include "dd.h" 35 #include "extern.h" 36 37 static void dd_close __P((void)); 38 static void dd_in __P((void)); 39 static void setup __P((void)); 40 41 IO in, out; /* input/output state */ 42 STAT st; /* statistics */ 43 void (*cfunc)(); /* conversion function */ 44 u_long cpy_cnt; /* # of blocks to copy */ 45 u_int ddflags; /* conversion options */ 46 u_int cbsz; /* conversion block size */ 47 u_int files_cnt = 1; /* # of files to copy */ 48 int errstats; /* show statistics on error */ 49 u_char *ctab; /* conversion table */ 50 51 main(argc, argv) 52 int argc; 53 char **argv; 54 { 55 jcl(argv); 56 setup(); 57 58 (void)signal(SIGINFO, summary); 59 (void)signal(SIGINT, terminate); 60 61 for (errstats = 1; files_cnt--;) 62 dd_in(); 63 64 dd_close(); 65 summary(0); 66 exit(0); 67 } 68 69 static void 70 setup() 71 { 72 register u_int cnt; 73 struct stat sb; 74 struct mtget mt; 75 76 if (in.name == NULL) { 77 in.name = "stdin"; 78 in.fd = STDIN_FILENO; 79 } else { 80 in.fd = open(in.name, O_RDONLY, 0); 81 if (in.fd < 0) 82 err("%s: %s", in.name, strerror(errno)); 83 } 84 85 if (fstat(in.fd, &sb)) 86 err("%s: %s", in.name, strerror(errno)); 87 if (S_ISCHR(sb.st_mode)) 88 in.flags |= ioctl(in.fd, MTIOCGET, &mt) ? ISCHR : ISTAPE; 89 else if (lseek(in.fd, 0L, SEEK_CUR) == -1 && errno == ESPIPE) 90 in.flags |= ISPIPE; /* XXX fixed in 4.4BSD */ 91 92 if (files_cnt > 1 && !(in.flags & ISTAPE)) 93 err("files is not supported for non-tape devices"); 94 95 if (out.name == NULL) { 96 /* No way to check for read access here. */ 97 out.fd = STDOUT_FILENO; 98 out.name = "stdout"; 99 } else { 100 #define OFLAGS \ 101 (O_CREAT | (ddflags & (C_SEEK | C_NOTRUNC) ? 0 : O_TRUNC)) 102 out.fd = open(out.name, O_RDWR | OFLAGS, DEFFILEMODE); 103 /* 104 * May not have read access, so try again with write only. 105 * Without read we may have a problem if output also does 106 * not support seeks. 107 */ 108 if (out.fd < 0) { 109 out.fd = open(out.name, O_WRONLY | OFLAGS, DEFFILEMODE); 110 out.flags |= NOREAD; 111 } 112 if (out.fd < 0) 113 err("%s: %s", out.name, strerror(errno)); 114 } 115 116 if (fstat(out.fd, &sb)) 117 err("%s: %s", out.name, strerror(errno)); 118 if (S_ISCHR(sb.st_mode)) 119 out.flags |= ioctl(out.fd, MTIOCGET, &mt) ? ISCHR : ISTAPE; 120 else if (lseek(out.fd, 0L, SEEK_CUR) == -1 && errno == ESPIPE) 121 out.flags |= ISPIPE; /* XXX fixed in 4.4BSD */ 122 123 /* 124 * Allocate space for the input and output buffers. If not doing 125 * record oriented I/O, only need a single buffer. 126 */ 127 if (!(ddflags & (C_BLOCK|C_UNBLOCK))) { 128 if ((in.db = malloc(out.dbsz + in.dbsz - 1)) == NULL) 129 err("%s", strerror(errno)); 130 out.db = in.db; 131 } else if ((in.db = 132 malloc((u_int)(MAX(in.dbsz, cbsz) + cbsz))) == NULL || 133 (out.db = malloc((u_int)(out.dbsz + cbsz))) == NULL) 134 err("%s", strerror(errno)); 135 in.dbp = in.db; 136 out.dbp = out.db; 137 138 /* Position the input/output streams. */ 139 if (in.offset) 140 pos_in(); 141 if (out.offset) 142 pos_out(); 143 144 /* 145 * Truncate the output file; ignore errors because it fails on some 146 * kinds of output files, tapes, for example. 147 */ 148 if (ddflags & (C_OF | C_SEEK | C_NOTRUNC) == (C_OF | C_SEEK)) 149 (void)ftruncate(out.fd, (off_t)out.offset * out.dbsz); 150 151 /* 152 * If converting case at the same time as another conversion, build a 153 * table that does both at once. If just converting case, use the 154 * built-in tables. 155 */ 156 if (ddflags & (C_LCASE|C_UCASE)) 157 if (ddflags & C_ASCII) 158 if (ddflags & C_LCASE) { 159 for (cnt = 0; cnt < 0377; ++cnt) 160 if (isupper(ctab[cnt])) 161 ctab[cnt] = tolower(ctab[cnt]); 162 } else { 163 for (cnt = 0; cnt < 0377; ++cnt) 164 if (islower(ctab[cnt])) 165 ctab[cnt] = toupper(ctab[cnt]); 166 } 167 else if (ddflags & C_EBCDIC) 168 if (ddflags & C_LCASE) { 169 for (cnt = 0; cnt < 0377; ++cnt) 170 if (isupper(cnt)) 171 ctab[cnt] = ctab[tolower(cnt)]; 172 } else { 173 for (cnt = 0; cnt < 0377; ++cnt) 174 if (islower(cnt)) 175 ctab[cnt] = ctab[toupper(cnt)]; 176 } 177 else 178 ctab = ddflags & C_LCASE ? u2l : l2u; 179 (void)time(&st.start); /* Statistics timestamp. */ 180 } 181 182 static void 183 dd_in() 184 { 185 register int flags, n; 186 187 for(flags = ddflags;;) { 188 if (cpy_cnt && (st.in_full + st.in_part) >= cpy_cnt) 189 return; 190 191 /* 192 * Zero the buffer first if trying to recover from errors so 193 * lose the minimum amount of data. If doing block operations 194 * use spaces. 195 */ 196 if (flags & (C_NOERROR|C_SYNC)) 197 if (flags & (C_BLOCK|C_UNBLOCK)) 198 memset(in.dbp, ' ', in.dbsz); 199 else 200 bzero(in.dbp, in.dbsz); 201 202 n = read(in.fd, in.dbp, in.dbsz); 203 if (n == 0) { 204 in.dbrcnt = 0; 205 return; 206 } 207 208 /* Read error. */ 209 if (n < 0) { 210 /* 211 * If noerror not specified, die. POSIX requires that 212 * the warning message be followed by an I/O display. 213 */ 214 if (!(flags & C_NOERROR)) 215 err("%s: %s", in.name, strerror(errno)); 216 warn("%s: %s", in.name, strerror(errno)); 217 summary(0); 218 219 /* 220 * If it's not a tape drive or a pipe, seek past the 221 * error. If your OS doesn't do the right thing for 222 * raw disks this section should be modified to re-read 223 * in sector size chunks. 224 */ 225 if (!(in.flags & (ISPIPE|ISTAPE)) && 226 lseek(in.fd, (off_t)in.dbsz, SEEK_CUR)) 227 warn("%s: %s", in.name, strerror(errno)); 228 229 /* If sync not specified, omit block and continue. */ 230 if (!(ddflags & C_SYNC)) 231 continue; 232 233 /* Read errors count as full blocks. */ 234 in.dbcnt += in.dbrcnt = in.dbsz; 235 ++st.in_full; 236 237 /* Handle full input blocks. */ 238 } else if (n == in.dbsz) { 239 in.dbcnt += in.dbrcnt = n; 240 ++st.in_full; 241 242 /* Handle partial input blocks. */ 243 } else if (n != in.dbsz) { 244 /* If sync, use the entire block. */ 245 if (ddflags & C_SYNC) 246 in.dbcnt += in.dbrcnt = in.dbsz; 247 else 248 in.dbcnt += in.dbrcnt = n; 249 ++st.in_part; 250 } 251 252 /* 253 * POSIX states that if bs is set and no other conversions 254 * than noerror, notrunc or sync are specified, the block 255 * is output without buffering as it is read. 256 */ 257 if (ddflags & C_BS) { 258 out.dbcnt = in.dbcnt; 259 dd_out(1); 260 in.dbcnt = 0; 261 continue; 262 } 263 264 if (ddflags & C_SWAB) { 265 if ((n = in.dbcnt) & 1) { 266 ++st.swab; 267 --n; 268 } 269 swab(in.dbp, in.dbp, n); 270 } 271 272 in.dbp += in.dbrcnt; 273 (*cfunc)(); 274 } 275 } 276 277 /* 278 * Cleanup any remaining I/O and flush output. If necesssary, output file 279 * is truncated. 280 */ 281 static void 282 dd_close() 283 { 284 if (cfunc == def) 285 def_close(); 286 else if (cfunc == block) 287 block_close(); 288 else if (cfunc == unblock) 289 unblock_close(); 290 if (out.dbcnt) 291 dd_out(1); 292 } 293 294 void 295 dd_out(force) 296 int force; 297 { 298 static int warned; 299 register int cnt, n, nw; 300 register u_char *outp; 301 302 /* 303 * Write one or more blocks out. The common case is writing a full 304 * output block in a single write; increment the full block stats. 305 * Otherwise, we're into partial block writes. If a partial write, 306 * and it's a character device, just warn. If a tape device, quit. 307 * 308 * The partial writes represent two cases. 1: Where the input block 309 * was less than expected so the output block was less than expected. 310 * 2: Where the input block was the right size but we were forced to 311 * write the block in multiple chunks. The original versions of dd(1) 312 * never wrote a block in more than a single write, so the latter case 313 * never happened. 314 * 315 * One special case is if we're forced to do the write -- in that case 316 * we play games with the buffer size, and it's usually a partial write. 317 */ 318 outp = out.db; 319 for (n = force ? out.dbcnt : out.dbsz;; n = out.dbsz) { 320 for (cnt = n;; cnt -= nw) { 321 outp += nw = write(out.fd, outp, cnt); 322 st.bytes += nw; 323 if (nw == n) { 324 if (n != out.dbsz) 325 ++st.out_part; 326 else 327 ++st.out_full; 328 break; 329 } 330 if (nw < 0) 331 err("%s: %s", out.name, strerror(errno)); 332 ++st.out_part; 333 if (nw == cnt) 334 break; 335 if (out.flags & ISCHR && !warned) { 336 warned = 1; 337 warn("%s: short write on character device", 338 out.name); 339 } 340 if (out.flags & ISTAPE) 341 err("%s: short write on tape device", out.name); 342 } 343 if ((out.dbcnt -= n) < out.dbsz) 344 break; 345 } 346 347 /* Reassemble the output block. */ 348 if (out.dbcnt) 349 bcopy(out.dbp - out.dbcnt, out.db, out.dbcnt); 350 out.dbp = out.db + out.dbcnt; 351 } 352