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 5.13 (Berkeley) 09/02/92"; 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 int 52 main(argc, argv) 53 int argc; 54 char *argv[]; 55 { 56 jcl(argv); 57 setup(); 58 59 (void)signal(SIGINFO, summary); 60 (void)signal(SIGINT, terminate); 61 62 for (errstats = 1; files_cnt--;) 63 dd_in(); 64 65 dd_close(); 66 summary(0); 67 exit(0); 68 } 69 70 static void 71 setup() 72 { 73 register u_int cnt; 74 struct stat sb; 75 struct mtget mt; 76 77 if (in.name == NULL) { 78 in.name = "stdin"; 79 in.fd = STDIN_FILENO; 80 } else { 81 in.fd = open(in.name, O_RDONLY, 0); 82 if (in.fd < 0) 83 err("%s: %s", in.name, strerror(errno)); 84 } 85 86 if (fstat(in.fd, &sb)) 87 err("%s: %s", in.name, strerror(errno)); 88 if (S_ISCHR(sb.st_mode)) 89 in.flags |= ioctl(in.fd, MTIOCGET, &mt) ? ISCHR : ISTAPE; 90 else if (lseek(in.fd, (off_t)0, SEEK_CUR) == -1 && errno == ESPIPE) 91 in.flags |= ISPIPE; /* XXX fixed in 4.4BSD */ 92 93 if (files_cnt > 1 && !(in.flags & ISTAPE)) 94 err("files is not supported for non-tape devices"); 95 96 if (out.name == NULL) { 97 /* No way to check for read access here. */ 98 out.fd = STDOUT_FILENO; 99 out.name = "stdout"; 100 } else { 101 #define OFLAGS \ 102 (O_CREAT | (ddflags & (C_SEEK | C_NOTRUNC) ? 0 : O_TRUNC)) 103 out.fd = open(out.name, O_RDWR | OFLAGS, DEFFILEMODE); 104 /* 105 * May not have read access, so try again with write only. 106 * Without read we may have a problem if output also does 107 * not support seeks. 108 */ 109 if (out.fd < 0) { 110 out.fd = open(out.name, O_WRONLY | OFLAGS, DEFFILEMODE); 111 out.flags |= NOREAD; 112 } 113 if (out.fd < 0) 114 err("%s: %s", out.name, strerror(errno)); 115 } 116 117 if (fstat(out.fd, &sb)) 118 err("%s: %s", out.name, strerror(errno)); 119 if (S_ISCHR(sb.st_mode)) 120 out.flags |= ioctl(out.fd, MTIOCGET, &mt) ? ISCHR : ISTAPE; 121 else if (lseek(out.fd, (off_t)0, SEEK_CUR) == -1 && errno == ESPIPE) 122 out.flags |= ISPIPE; /* XXX fixed in 4.4BSD */ 123 124 /* 125 * Allocate space for the input and output buffers. If not doing 126 * record oriented I/O, only need a single buffer. 127 */ 128 if (!(ddflags & (C_BLOCK|C_UNBLOCK))) { 129 if ((in.db = malloc(out.dbsz + in.dbsz - 1)) == NULL) 130 err("%s", strerror(errno)); 131 out.db = in.db; 132 } else if ((in.db = 133 malloc((u_int)(MAX(in.dbsz, cbsz) + cbsz))) == NULL || 134 (out.db = malloc((u_int)(out.dbsz + cbsz))) == NULL) 135 err("%s", strerror(errno)); 136 in.dbp = in.db; 137 out.dbp = out.db; 138 139 /* Position the input/output streams. */ 140 if (in.offset) 141 pos_in(); 142 if (out.offset) 143 pos_out(); 144 145 /* 146 * Truncate the output file; ignore errors because it fails on some 147 * kinds of output files, tapes, for example. 148 */ 149 if (ddflags & (C_OF | C_SEEK | C_NOTRUNC) == (C_OF | C_SEEK)) 150 (void)ftruncate(out.fd, (off_t)out.offset * out.dbsz); 151 152 /* 153 * If converting case at the same time as another conversion, build a 154 * table that does both at once. If just converting case, use the 155 * built-in tables. 156 */ 157 if (ddflags & (C_LCASE|C_UCASE)) 158 if (ddflags & C_ASCII) 159 if (ddflags & C_LCASE) { 160 for (cnt = 0; cnt < 0377; ++cnt) 161 if (isupper(ctab[cnt])) 162 ctab[cnt] = tolower(ctab[cnt]); 163 } else { 164 for (cnt = 0; cnt < 0377; ++cnt) 165 if (islower(ctab[cnt])) 166 ctab[cnt] = toupper(ctab[cnt]); 167 } 168 else if (ddflags & C_EBCDIC) 169 if (ddflags & C_LCASE) { 170 for (cnt = 0; cnt < 0377; ++cnt) 171 if (isupper(cnt)) 172 ctab[cnt] = ctab[tolower(cnt)]; 173 } else { 174 for (cnt = 0; cnt < 0377; ++cnt) 175 if (islower(cnt)) 176 ctab[cnt] = ctab[toupper(cnt)]; 177 } 178 else 179 ctab = ddflags & C_LCASE ? u2l : l2u; 180 (void)time(&st.start); /* Statistics timestamp. */ 181 } 182 183 static void 184 dd_in() 185 { 186 register int flags, n; 187 188 for(flags = ddflags;;) { 189 if (cpy_cnt && (st.in_full + st.in_part) >= cpy_cnt) 190 return; 191 192 /* 193 * Zero the buffer first if trying to recover from errors so 194 * lose the minimum amount of data. If doing block operations 195 * use spaces. 196 */ 197 if (flags & (C_NOERROR|C_SYNC)) 198 if (flags & (C_BLOCK|C_UNBLOCK)) 199 memset(in.dbp, ' ', in.dbsz); 200 else 201 bzero(in.dbp, in.dbsz); 202 203 n = read(in.fd, in.dbp, in.dbsz); 204 if (n == 0) { 205 in.dbrcnt = 0; 206 return; 207 } 208 209 /* Read error. */ 210 if (n < 0) { 211 /* 212 * If noerror not specified, die. POSIX requires that 213 * the warning message be followed by an I/O display. 214 */ 215 if (!(flags & C_NOERROR)) 216 err("%s: %s", in.name, strerror(errno)); 217 warn("%s: %s", in.name, strerror(errno)); 218 summary(0); 219 220 /* 221 * If it's not a tape drive or a pipe, seek past the 222 * error. If your OS doesn't do the right thing for 223 * raw disks this section should be modified to re-read 224 * in sector size chunks. 225 */ 226 if (!(in.flags & (ISPIPE|ISTAPE)) && 227 lseek(in.fd, (off_t)in.dbsz, SEEK_CUR)) 228 warn("%s: %s", in.name, strerror(errno)); 229 230 /* If sync not specified, omit block and continue. */ 231 if (!(ddflags & C_SYNC)) 232 continue; 233 234 /* Read errors count as full blocks. */ 235 in.dbcnt += in.dbrcnt = in.dbsz; 236 ++st.in_full; 237 238 /* Handle full input blocks. */ 239 } else if (n == in.dbsz) { 240 in.dbcnt += in.dbrcnt = n; 241 ++st.in_full; 242 243 /* Handle partial input blocks. */ 244 } else if (n != in.dbsz) { 245 /* If sync, use the entire block. */ 246 if (ddflags & C_SYNC) 247 in.dbcnt += in.dbrcnt = in.dbsz; 248 else 249 in.dbcnt += in.dbrcnt = n; 250 ++st.in_part; 251 } 252 253 /* 254 * POSIX states that if bs is set and no other conversions 255 * than noerror, notrunc or sync are specified, the block 256 * is output without buffering as it is read. 257 */ 258 if (ddflags & C_BS) { 259 out.dbcnt = in.dbcnt; 260 dd_out(1); 261 in.dbcnt = 0; 262 continue; 263 } 264 265 if (ddflags & C_SWAB) { 266 if ((n = in.dbcnt) & 1) { 267 ++st.swab; 268 --n; 269 } 270 swab(in.dbp, in.dbp, n); 271 } 272 273 in.dbp += in.dbrcnt; 274 (*cfunc)(); 275 } 276 } 277 278 /* 279 * Cleanup any remaining I/O and flush output. If necesssary, output file 280 * is truncated. 281 */ 282 static void 283 dd_close() 284 { 285 if (cfunc == def) 286 def_close(); 287 else if (cfunc == block) 288 block_close(); 289 else if (cfunc == unblock) 290 unblock_close(); 291 if (out.dbcnt) 292 dd_out(1); 293 } 294 295 void 296 dd_out(force) 297 int force; 298 { 299 static int warned; 300 register int cnt, n, nw; 301 register u_char *outp; 302 303 /* 304 * Write one or more blocks out. The common case is writing a full 305 * output block in a single write; increment the full block stats. 306 * Otherwise, we're into partial block writes. If a partial write, 307 * and it's a character device, just warn. If a tape device, quit. 308 * 309 * The partial writes represent two cases. 1: Where the input block 310 * was less than expected so the output block was less than expected. 311 * 2: Where the input block was the right size but we were forced to 312 * write the block in multiple chunks. The original versions of dd(1) 313 * never wrote a block in more than a single write, so the latter case 314 * never happened. 315 * 316 * One special case is if we're forced to do the write -- in that case 317 * we play games with the buffer size, and it's usually a partial write. 318 */ 319 outp = out.db; 320 for (n = force ? out.dbcnt : out.dbsz;; n = out.dbsz) { 321 for (cnt = n;; cnt -= nw) { 322 outp += nw = write(out.fd, outp, cnt); 323 st.bytes += nw; 324 if (nw == n) { 325 if (n != out.dbsz) 326 ++st.out_part; 327 else 328 ++st.out_full; 329 break; 330 } 331 if (nw < 0) 332 err("%s: %s", out.name, strerror(errno)); 333 ++st.out_part; 334 if (nw == cnt) 335 break; 336 if (out.flags & ISCHR && !warned) { 337 warned = 1; 338 warn("%s: short write on character device", 339 out.name); 340 } 341 if (out.flags & ISTAPE) 342 err("%s: short write on tape device", out.name); 343 } 344 if ((out.dbcnt -= n) < out.dbsz) 345 break; 346 } 347 348 /* Reassemble the output block. */ 349 if (out.dbcnt) 350 bcopy(out.dbp - out.dbcnt, out.db, out.dbcnt); 351 out.dbp = out.db + out.dbcnt; 352 } 353