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 5.11 (Berkeley) 08/23/91"; 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 #define OFLAGS \ 100 (O_CREAT | (ddflags & (C_SEEK | C_NOTRUNC) ? 0 : O_TRUNC)) 101 out.fd = open(out.name, O_RDWR | OFLAGS, DEFFILEMODE); 102 /* 103 * May not have read access, so try again with write only. 104 * Without read we may have a problem if output also does 105 * not support seeks. 106 */ 107 if (out.fd < 0) { 108 out.fd = open(out.name, O_WRONLY | OFLAGS, DEFFILEMODE); 109 out.flags |= NOREAD; 110 } 111 if (out.fd < 0) 112 err("%s: %s", out.name, strerror(errno)); 113 } 114 115 if (fstat(out.fd, &sb)) 116 err("%s: %s", out.name, strerror(errno)); 117 if (S_ISCHR(sb.st_mode)) 118 out.flags |= ioctl(out.fd, MTIOCGET, &mt) ? ISCHR : ISTAPE; 119 else if (lseek(out.fd, 0L, SEEK_CUR) == -1 && errno == ESPIPE) 120 out.flags |= ISPIPE; /* XXX fixed in 4.4BSD */ 121 122 /* 123 * Allocate space for the input and output buffers. If not doing 124 * record oriented I/O, only need a single buffer. 125 */ 126 if (!(ddflags & (C_BLOCK|C_UNBLOCK))) { 127 if ((in.db = malloc(out.dbsz + in.dbsz - 1)) == NULL) 128 err("%s", strerror(errno)); 129 out.db = in.db; 130 } else if ((in.db = 131 malloc((u_int)(MAX(in.dbsz, cbsz) + cbsz))) == NULL || 132 (out.db = malloc((u_int)(out.dbsz + cbsz))) == NULL) 133 err("%s", strerror(errno)); 134 in.dbp = in.db; 135 out.dbp = out.db; 136 137 /* Position the input/output streams. */ 138 if (in.offset) 139 pos_in(); 140 if (out.offset) 141 pos_out(); 142 143 /* 144 * Truncate the output file; ignore errors because it fails on some 145 * kinds of output files, tapes, for example. 146 */ 147 if (ddflags & (C_OF | C_SEEK | C_NOTRUNC) == (C_OF | C_SEEK)) 148 (void)ftruncate(out.fd, (off_t)out.offset * out.dbsz); 149 150 /* 151 * If converting case at the same time as another conversion, build a 152 * table that does both at once. If just converting case, use the 153 * built-in tables. 154 */ 155 if (ddflags & (C_LCASE|C_UCASE)) 156 if (ddflags & C_ASCII) 157 if (ddflags & C_LCASE) { 158 for (cnt = 0; cnt < 0377; ++cnt) 159 if (isupper(ctab[cnt])) 160 ctab[cnt] = tolower(ctab[cnt]); 161 } else { 162 for (cnt = 0; cnt < 0377; ++cnt) 163 if (islower(ctab[cnt])) 164 ctab[cnt] = toupper(ctab[cnt]); 165 } 166 else if (ddflags & C_EBCDIC) 167 if (ddflags & C_LCASE) { 168 for (cnt = 0; cnt < 0377; ++cnt) 169 if (isupper(cnt)) 170 ctab[cnt] = ctab[tolower(cnt)]; 171 } else { 172 for (cnt = 0; cnt < 0377; ++cnt) 173 if (islower(cnt)) 174 ctab[cnt] = ctab[toupper(cnt)]; 175 } 176 else 177 ctab = ddflags & C_LCASE ? u2l : l2u; 178 } 179 180 static void 181 dd_in() 182 { 183 register int flags, n; 184 185 for(flags = ddflags;;) { 186 if (cpy_cnt && (st.in_full + st.in_part) >= cpy_cnt) 187 return; 188 189 /* 190 * Zero the buffer first if trying to recover from errors so 191 * lose the minimum amount of data. If doing block operations 192 * use spaces. 193 */ 194 if (flags & (C_NOERROR|C_SYNC)) 195 if (flags & (C_BLOCK|C_UNBLOCK)) 196 memset(in.dbp, ' ', in.dbsz); 197 else 198 bzero(in.dbp, in.dbsz); 199 200 n = read(in.fd, in.dbp, in.dbsz); 201 if (n == 0) { 202 in.dbrcnt = 0; 203 return; 204 } 205 206 /* Read error. */ 207 if (n < 0) { 208 /* 209 * If noerror not specified, die. POSIX requires that 210 * the warning message be followed by an I/O display. 211 */ 212 if (!(flags & C_NOERROR)) 213 err("%s: %s", in.name, strerror(errno)); 214 warn("%s: %s", in.name, strerror(errno)); 215 summary(0); 216 217 /* 218 * If it's not a tape drive or a pipe, seek past the 219 * error. If your OS doesn't do the right thing for 220 * raw disks this section should be modified to re-read 221 * in sector size chunks. 222 */ 223 if (!(in.flags & (ISPIPE|ISTAPE)) && 224 lseek(in.fd, (off_t)in.dbsz, SEEK_CUR)) 225 warn("%s: %s", in.name, strerror(errno)); 226 227 /* If sync not specified, omit block and continue. */ 228 if (!(ddflags & C_SYNC)) 229 continue; 230 231 /* Read errors count as full blocks. */ 232 in.dbcnt += in.dbrcnt = in.dbsz; 233 ++st.in_full; 234 235 /* Handle full input blocks. */ 236 } else if (n == in.dbsz) { 237 in.dbcnt += in.dbrcnt = n; 238 ++st.in_full; 239 240 /* Handle partial input blocks. */ 241 } else if (n != in.dbsz) { 242 /* If sync, use the entire block. */ 243 if (ddflags & C_SYNC) 244 in.dbcnt += in.dbrcnt = in.dbsz; 245 else 246 in.dbcnt += in.dbrcnt = n; 247 ++st.in_part; 248 } 249 250 /* 251 * POSIX states that if bs is set and no other conversions 252 * than noerror, notrunc or sync are specified, the block 253 * is output without buffering as it is read. 254 */ 255 if (ddflags & C_BS) { 256 out.dbcnt = in.dbcnt; 257 dd_out(1); 258 in.dbcnt = 0; 259 continue; 260 } 261 262 if (ddflags & C_SWAB) { 263 if ((n = in.dbcnt) & 1) { 264 ++st.swab; 265 --n; 266 } 267 swab(in.dbp, in.dbp, n); 268 } 269 270 in.dbp += in.dbrcnt; 271 (*cfunc)(); 272 } 273 } 274 275 /* 276 * Cleanup any remaining I/O and flush output. If necesssary, output file 277 * is truncated. 278 */ 279 static void 280 dd_close() 281 { 282 if (cfunc == def) 283 def_close(); 284 else if (cfunc == block) 285 block_close(); 286 else if (cfunc == unblock) 287 unblock_close(); 288 if (out.dbcnt) 289 dd_out(1); 290 } 291 292 void 293 dd_out(force) 294 int force; 295 { 296 static int warned; 297 register int cnt, n, nw; 298 register u_char *outp; 299 300 /* 301 * Write one or more blocks out. The common case is writing a full 302 * output block in a single write; increment the full block stats. 303 * Otherwise, we're into partial block writes. If a partial write, 304 * and it's a character device, just warn. If a tape device, quit. 305 * 306 * The partial writes represent two cases. 1: Where the input block 307 * was less than expected so the output block was less than expected. 308 * 2: Where the input block was the right size but we were forced to 309 * write the block in multiple chunks. The original versions of dd(1) 310 * never wrote a block in more than a single write, so the latter case 311 * never happened. 312 * 313 * One special case is if we're forced to do the write -- in that case 314 * we play games with the buffer size, and it's usually a partial write. 315 */ 316 outp = out.db; 317 for (n = force ? out.dbcnt : out.dbsz;; n = out.dbsz) { 318 for (cnt = n;; cnt -= nw) { 319 outp += nw = write(out.fd, outp, cnt); 320 if (nw == n) { 321 if (n != out.dbsz) 322 ++st.out_part; 323 else 324 ++st.out_full; 325 break; 326 } 327 if (nw < 0) 328 err("%s: %s", out.name, strerror(errno)); 329 ++st.out_part; 330 if (nw == cnt) 331 break; 332 if (out.flags & ISCHR && !warned) { 333 warned = 1; 334 warn("%s: short write on character device", 335 out.name); 336 } 337 if (out.flags & ISTAPE) 338 err("%s: short write on tape device", out.name); 339 } 340 if ((out.dbcnt -= n) < out.dbsz) 341 break; 342 } 343 344 /* Reassemble the output block. */ 345 if (out.dbcnt) 346 bcopy(out.dbp - out.dbcnt, out.db, out.dbcnt); 347 out.dbp = out.db + out.dbcnt; 348 } 349