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 5.9 (Berkeley) 07/29/91"; 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 u_char *ctab; /* conversion table */ 49 50 main(argc, argv) 51 int argc; 52 char **argv; 53 { 54 jcl(argv); 55 setup(); 56 57 (void)signal(SIGINFO, summary); 58 (void)signal(SIGINT, terminate); 59 60 while (files_cnt--) 61 dd_in(); 62 63 dd_close(); 64 summary(0); 65 exit(0); 66 } 67 68 static void 69 setup() 70 { 71 register u_int cnt; 72 struct stat sb; 73 struct mtget mt; 74 75 if (in.name == NULL) { 76 in.name = "stdin"; 77 in.fd = STDIN_FILENO; 78 } else { 79 in.fd = open(in.name, O_RDONLY, 0); 80 if (in.fd < 0) 81 err("%s: %s", in.name, strerror(errno)); 82 } 83 84 if (fstat(in.fd, &sb)) 85 err("%s: %s", in.name, strerror(errno)); 86 if (S_ISCHR(sb.st_mode)) 87 in.flags |= ioctl(in.fd, MTIOCGET, &mt) ? ISCHR : ISTAPE; 88 else if (lseek(in.fd, 0L, SEEK_CUR) == -1 && errno == ESPIPE) 89 in.flags |= ISPIPE; /* XXX fixed in 4.4BSD */ 90 91 if (files_cnt > 1 && !(in.flags & ISTAPE)) 92 err("files is not supported for non-tape devices"); 93 94 if (out.name == NULL) { 95 /* No way to check for read access here. */ 96 out.fd = STDOUT_FILENO; 97 out.name = "stdout"; 98 } else { 99 out.fd = open(out.name, O_RDWR|O_CREAT, DEFFILEMODE); 100 /* 101 * May not have read access, so try again with write only. 102 * Without read we may have a problem if output also does 103 * not support seeks. 104 */ 105 if (out.fd < 0) { 106 out.fd = open(out.name, O_WRONLY|O_CREAT, DEFFILEMODE); 107 out.flags |= NOREAD; 108 } 109 if (out.fd < 0) 110 err("%s: %s", out.name, strerror(errno)); 111 } 112 113 if (fstat(out.fd, &sb)) 114 err("%s: %s", out.name, strerror(errno)); 115 if (S_ISCHR(sb.st_mode)) 116 out.flags |= ioctl(out.fd, MTIOCGET, &mt) ? ISCHR : ISTAPE; 117 else if (lseek(out.fd, 0L, SEEK_CUR) == -1 && errno == ESPIPE) 118 out.flags |= ISPIPE; /* XXX fixed in 4.4BSD */ 119 120 /* 121 * Allocate space for the input and output buffers. If not doing 122 * record oriented I/O, only need a single buffer. 123 */ 124 if (!(ddflags & (C_BLOCK|C_UNBLOCK))) { 125 if (in.dbsz > out.dbsz) 126 cnt = in.dbsz - 1 - in.dbsz / 2 + in.dbsz; 127 else if (in.dbsz < out.dbsz) 128 cnt = out.dbsz + in.dbsz - 1; 129 else 130 cnt = in.dbsz; 131 if ((in.db = malloc(cnt)) == 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 /* Truncate the output file. */ 148 if (ddflags & C_NOTRUNC) { 149 if (out.flags & ISTAPE) 150 err("notrunc is not supported for tape devices"); 151 } else if (S_ISREG(sb.st_mode) && ftruncate(out.fd, 152 (off_t)out.offset * out.dbsz)) 153 err("%s: truncate: %s", out.name, strerror(errno)); 154 155 /* 156 * If converting case at the same time as another conversion, build a 157 * table that does both at once. If just converting case, use the 158 * built-in tables. 159 */ 160 if (ddflags & (C_LCASE|C_UCASE)) 161 if (ddflags & C_ASCII) 162 if (ddflags & C_LCASE) { 163 for (cnt = 0; cnt < 0377; ++cnt) 164 if (isupper(ctab[cnt])) 165 ctab[cnt] = tolower(ctab[cnt]); 166 } else { 167 for (cnt = 0; cnt < 0377; ++cnt) 168 if (islower(ctab[cnt])) 169 ctab[cnt] = toupper(ctab[cnt]); 170 } 171 else if (ddflags & C_EBCDIC) 172 if (ddflags & C_LCASE) { 173 for (cnt = 0; cnt < 0377; ++cnt) 174 if (isupper(cnt)) 175 ctab[cnt] = ctab[tolower(cnt)]; 176 } else { 177 for (cnt = 0; cnt < 0377; ++cnt) 178 if (islower(cnt)) 179 ctab[cnt] = ctab[toupper(cnt)]; 180 } 181 else 182 ctab = ddflags & C_LCASE ? u2l : l2u; 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)) 200 if (flags & (C_BLOCK|C_UNBLOCK)) 201 memset(in.dbp, ' ', in.dbsz); 202 else 203 bzero(in.dbp, 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 if (n != in.dbsz) { 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 (out.dbcnt) 294 dd_out(1); 295 } 296 297 void 298 dd_out(force) 299 int force; 300 { 301 static int warned; 302 register int cnt, n, nw; 303 register u_char *outp; 304 305 /* 306 * Write one or more blocks out. The common case is writing a full 307 * output block in a single write; increment the full block stats. 308 * Otherwise, we're into partial block writes. If a partial write, 309 * and it's a character device, just warn. If a tape device, quit. 310 * 311 * The partial writes represent two cases. 1: Where the input block 312 * was less than expected so the output block was less than expected. 313 * 2: Where the input block was the right size but we were forced to 314 * write the block in multiple chunks. The original versions of dd(1) 315 * never wrote a block in more than a single write, so the latter case 316 * never happened. 317 * 318 * One special case is if we're forced to do the write -- in that case 319 * we play games with the buffer size, and it's usually a partial write. 320 */ 321 outp = out.db; 322 for (n = force ? out.dbcnt : out.dbsz;; n = out.dbsz) { 323 for (cnt = n;; cnt -= nw) { 324 outp += nw = write(out.fd, outp, cnt); 325 if (nw == n) { 326 if (n != out.dbsz) 327 ++st.out_part; 328 else 329 ++st.out_full; 330 break; 331 } 332 if (nw < 0) 333 err("%s: %s", out.name, strerror(errno)); 334 ++st.out_part; 335 if (nw == cnt) 336 break; 337 if (out.flags & ISCHR && !warned) { 338 warned = 1; 339 warn("%s: short write on character device", 340 out.name); 341 } 342 if (out.flags & ISTAPE) 343 err("%s: short write on tape device", out.name); 344 } 345 if ((out.dbcnt -= n) < out.dbsz) 346 break; 347 } 348 349 /* Reassemble the output block. */ 350 if (out.dbcnt) 351 bcopy(out.dbp - out.dbcnt, out.db, out.dbcnt); 352 out.dbp = out.db + out.dbcnt; 353 } 354