2 * SPDX-License-Identifier: BSD-3-Clause
4 * Copyright (c) 1991, 1993, 1994
5 * The Regents of the University of California. All rights reserved.
7 * This code is derived from software contributed to Berkeley by
8 * Keith Muller of the University of California, San Diego and Lance
9 * Visser of Convex Computer Corporation.
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 4. Neither the name of the University nor the names of its contributors
20 * may be used to endorse or promote products derived from this software
21 * without specific prior written permission.
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38 static char const copyright[] =
39 "@(#) Copyright (c) 1991, 1993, 1994\n\
40 The Regents of the University of California. All rights reserved.\n";
44 static char sccsid[] = "@(#)dd.c 8.5 (Berkeley) 4/2/94";
47 #include <sys/cdefs.h>
48 __FBSDID("$FreeBSD$");
50 #include <sys/param.h>
53 #include <sys/disklabel.h>
54 #include <sys/filio.h>
72 static void dd_close(void);
73 static void dd_in(void);
74 static void getfdtype(IO *);
75 static void setup(void);
77 IO in, out; /* input/output state */
78 STAT st; /* statistics */
79 void (*cfunc)(void); /* conversion function */
80 uintmax_t cpy_cnt; /* # of blocks to copy */
81 static off_t pending = 0; /* pending seek if sparse */
82 u_int ddflags = 0; /* conversion options */
83 size_t cbsz; /* conversion block size */
84 uintmax_t files_cnt = 1; /* # of files to copy */
85 const u_char *ctab; /* conversion table */
86 char fill_char; /* Character to fill with if defined */
87 size_t speed = 0; /* maximum speed, in bytes per second */
88 volatile sig_atomic_t need_summary;
91 main(int argc __unused, char *argv[])
93 (void)setlocale(LC_CTYPE, "");
97 (void)signal(SIGINFO, siginfo_handler);
98 (void)signal(SIGINT, terminate);
107 * Some devices such as cfi(4) may perform significant amounts
108 * of work when a write descriptor is closed. Close the out
109 * descriptor explicitly so that the summary handler (called
110 * from an atexit() hook) includes this work.
121 i = c ^ (c >> 1) ^ (c >> 2) ^ (c >> 3) ^
122 (c >> 4) ^ (c >> 5) ^ (c >> 6) ^ (c >> 7);
131 if (in.name == NULL) {
133 in.fd = STDIN_FILENO;
135 in.fd = open(in.name, O_RDONLY, 0);
137 err(1, "%s", in.name);
142 if (files_cnt > 1 && !(in.flags & ISTAPE))
143 errx(1, "files is not supported for non-tape devices");
145 if (out.name == NULL) {
146 /* No way to check for read access here. */
147 out.fd = STDOUT_FILENO;
151 (O_CREAT | (ddflags & (C_SEEK | C_NOTRUNC) ? 0 : O_TRUNC))
152 out.fd = open(out.name, O_RDWR | OFLAGS, DEFFILEMODE);
154 * May not have read access, so try again with write only.
155 * Without read we may have a problem if output also does
159 out.fd = open(out.name, O_WRONLY | OFLAGS, DEFFILEMODE);
163 err(1, "%s", out.name);
169 * Allocate space for the input and output buffers. If not doing
170 * record oriented I/O, only need a single buffer.
172 if (!(ddflags & (C_BLOCK | C_UNBLOCK))) {
173 if ((in.db = malloc(out.dbsz + in.dbsz - 1)) == NULL)
174 err(1, "input buffer");
176 } else if ((in.db = malloc(MAX(in.dbsz, cbsz) + cbsz)) == NULL ||
177 (out.db = malloc(out.dbsz + cbsz)) == NULL)
178 err(1, "output buffer");
180 /* dbp is the first free position in each buffer. */
184 /* Position the input/output streams. */
191 * Truncate the output file. If it fails on a type of output file
192 * that it should _not_ fail on, error out.
194 if ((ddflags & (C_OF | C_SEEK | C_NOTRUNC)) == (C_OF | C_SEEK) &&
196 if (ftruncate(out.fd, out.offset * out.dbsz) == -1)
197 err(1, "truncating %s", out.name);
199 if (ddflags & (C_LCASE | C_UCASE | C_ASCII | C_EBCDIC | C_PARITY)) {
201 for (cnt = 0; cnt <= 0377; ++cnt)
202 casetab[cnt] = ctab[cnt];
204 for (cnt = 0; cnt <= 0377; ++cnt)
207 if ((ddflags & C_PARITY) && !(ddflags & C_ASCII)) {
209 * If the input is not EBCDIC, and we do parity
210 * processing, strip input parity.
212 for (cnt = 200; cnt <= 0377; ++cnt)
213 casetab[cnt] = casetab[cnt & 0x7f];
215 if (ddflags & C_LCASE) {
216 for (cnt = 0; cnt <= 0377; ++cnt)
217 casetab[cnt] = tolower(casetab[cnt]);
218 } else if (ddflags & C_UCASE) {
219 for (cnt = 0; cnt <= 0377; ++cnt)
220 casetab[cnt] = toupper(casetab[cnt]);
222 if ((ddflags & C_PARITY)) {
224 * This should strictly speaking be a no-op, but I
225 * wonder what funny LANG settings could get us.
227 for (cnt = 0; cnt <= 0377; ++cnt)
228 casetab[cnt] = casetab[cnt] & 0x7f;
230 if ((ddflags & C_PARSET)) {
231 for (cnt = 0; cnt <= 0377; ++cnt)
232 casetab[cnt] = casetab[cnt] | 0x80;
234 if ((ddflags & C_PAREVEN)) {
235 for (cnt = 0; cnt <= 0377; ++cnt)
236 if (parity(casetab[cnt]))
237 casetab[cnt] = casetab[cnt] | 0x80;
239 if ((ddflags & C_PARODD)) {
240 for (cnt = 0; cnt <= 0377; ++cnt)
241 if (!parity(casetab[cnt]))
242 casetab[cnt] = casetab[cnt] | 0x80;
248 if (clock_gettime(CLOCK_MONOTONIC, &st.start))
249 err(1, "clock_gettime");
258 if (fstat(io->fd, &sb) == -1)
259 err(1, "%s", io->name);
260 if (S_ISREG(sb.st_mode))
261 io->flags |= ISTRUNC;
262 if (S_ISCHR(sb.st_mode) || S_ISBLK(sb.st_mode)) {
263 if (ioctl(io->fd, FIODTYPE, &type) == -1) {
264 err(1, "%s", io->name);
268 else if (type & (D_DISK | D_MEM))
270 if (S_ISCHR(sb.st_mode) && (type & D_TAPE) == 0)
276 if (lseek(io->fd, (off_t)0, SEEK_CUR) == -1 && errno == ESPIPE)
283 * Limit the speed by adding a delay before every block read.
284 * The delay (t_usleep) is equal to the time computed from block
285 * size and the specified speed limit (t_target) minus the time
286 * spent on actual read and write operations (t_io).
291 static double t_prev, t_usleep;
292 double t_now, t_io, t_target;
294 t_now = secs_elapsed();
295 t_io = t_now - t_prev - t_usleep;
296 t_target = (double)in.dbsz / (double)speed;
297 t_usleep = t_target - t_io;
299 usleep(t_usleep * 1000000);
306 swapbytes(void *v, size_t len)
308 unsigned char *p = v;
327 case -1: /* count=0 was specified */
332 if (st.in_full + st.in_part >= (uintmax_t)cpy_cnt)
341 * Zero the buffer first if sync; if doing block operations,
344 if (ddflags & C_SYNC) {
345 if (ddflags & C_FILL)
346 memset(in.dbp, fill_char, in.dbsz);
347 else if (ddflags & (C_BLOCK | C_UNBLOCK))
348 memset(in.dbp, ' ', in.dbsz);
350 memset(in.dbp, 0, in.dbsz);
353 n = read(in.fd, in.dbp, in.dbsz);
362 * If noerror not specified, die. POSIX requires that
363 * the warning message be followed by an I/O display.
365 if (!(ddflags & C_NOERROR))
366 err(1, "%s", in.name);
371 * If it's a seekable file descriptor, seek past the
372 * error. If your OS doesn't do the right thing for
373 * raw disks this section should be modified to re-read
374 * in sector size chunks.
376 if (in.flags & ISSEEK &&
377 lseek(in.fd, (off_t)in.dbsz, SEEK_CUR))
380 /* If sync not specified, omit block and continue. */
381 if (!(ddflags & C_SYNC))
384 /* Read errors count as full blocks. */
385 in.dbcnt += in.dbrcnt = in.dbsz;
388 /* Handle full input blocks. */
389 } else if ((size_t)n == in.dbsz) {
390 in.dbcnt += in.dbrcnt = n;
393 /* Handle partial input blocks. */
395 /* If sync, use the entire block. */
396 if (ddflags & C_SYNC)
397 in.dbcnt += in.dbrcnt = in.dbsz;
399 in.dbcnt += in.dbrcnt = n;
404 * POSIX states that if bs is set and no other conversions
405 * than noerror, notrunc or sync are specified, the block
406 * is output without buffering as it is read.
408 if ((ddflags & ~(C_NOERROR | C_NOTRUNC | C_SYNC)) == C_BS) {
409 out.dbcnt = in.dbcnt;
415 if (ddflags & C_SWAB) {
416 if ((n = in.dbrcnt) & 1) {
420 swapbytes(in.dbp, (size_t)n);
432 * Clean up any remaining I/O and flush output. If necessary, the output file
440 else if (cfunc == block)
442 else if (cfunc == unblock)
444 if (ddflags & C_OSYNC && out.dbcnt && out.dbcnt < out.dbsz) {
445 if (ddflags & C_FILL)
446 memset(out.dbp, fill_char, out.dbsz - out.dbcnt);
447 else if (ddflags & (C_BLOCK | C_UNBLOCK))
448 memset(out.dbp, ' ', out.dbsz - out.dbcnt);
450 memset(out.dbp, 0, out.dbsz - out.dbcnt);
451 out.dbcnt = out.dbsz;
453 if (out.dbcnt || pending)
457 * If the file ends with a hole, ftruncate it to extend its size
458 * up to the end of the hole (without having to write any data).
460 if (out.seek_offset > 0 && (out.flags & ISTRUNC)) {
461 if (ftruncate(out.fd, out.seek_offset) == -1)
462 err(1, "truncating %s", out.name);
476 * Write one or more blocks out. The common case is writing a full
477 * output block in a single write; increment the full block stats.
478 * Otherwise, we're into partial block writes. If a partial write,
479 * and it's a character device, just warn. If a tape device, quit.
481 * The partial writes represent two cases. 1: Where the input block
482 * was less than expected so the output block was less than expected.
483 * 2: Where the input block was the right size but we were forced to
484 * write the block in multiple chunks. The original versions of dd(1)
485 * never wrote a block in more than a single write, so the latter case
488 * One special case is if we're forced to do the write -- in that case
489 * we play games with the buffer size, and it's usually a partial write.
494 * If force, first try to write all pending data, else try to write
495 * just one block. Subsequently always write data one full block at
498 for (n = force ? out.dbcnt : out.dbsz;; n = out.dbsz) {
502 if (ddflags & C_SPARSE) {
503 sparse = 1; /* Is buffer sparse? */
504 for (i = 0; i < cnt; i++)
510 if (sparse && !force) {
516 * Seek past hole. Note that we need to record the
517 * reached offset, because we might have no more data
518 * to write, in which case we'll need to call
519 * ftruncate to extend the file size.
521 out.seek_offset = lseek(out.fd, pending, SEEK_CUR);
522 if (out.seek_offset == -1)
523 err(2, "%s: seek error creating sparse file",
528 nw = write(out.fd, outp, cnt);
537 errx(1, "%s: end of device", out.name);
539 err(1, "%s", out.name);
546 if ((size_t)nw == n && n == out.dbsz)
551 if ((size_t) nw != cnt) {
552 if (out.flags & ISTAPE)
553 errx(1, "%s: short write on tape device",
555 if (out.flags & ISCHR && !warned) {
557 warnx("%s: short write on character device",
565 if ((out.dbcnt -= n) < out.dbsz)
569 /* Reassemble the output block. */
571 (void)memmove(out.db, out.dbp - out.dbcnt, out.dbcnt);
572 out.dbp = out.db + out.dbcnt;