/bin/dd/dd.c
https://bitbucket.org/freebsd/freebsd-head/ · C · 494 lines · 347 code · 46 blank · 101 comment · 139 complexity · b19186900826ffcf14dffd34202d5e2a MD5 · raw file
- /*-
- * Copyright (c) 1991, 1993, 1994
- * The Regents of the University of California. All rights reserved.
- *
- * This code is derived from software contributed to Berkeley by
- * Keith Muller of the University of California, San Diego and Lance
- * Visser of Convex Computer Corporation.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- * 4. Neither the name of the University nor the names of its contributors
- * may be used to endorse or promote products derived from this software
- * without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- */
- #if 0
- #ifndef lint
- static char const copyright[] =
- "@(#) Copyright (c) 1991, 1993, 1994\n\
- The Regents of the University of California. All rights reserved.\n";
- #endif /* not lint */
- #ifndef lint
- static char sccsid[] = "@(#)dd.c 8.5 (Berkeley) 4/2/94";
- #endif /* not lint */
- #endif
- #include <sys/cdefs.h>
- __FBSDID("$FreeBSD$");
- #include <sys/param.h>
- #include <sys/stat.h>
- #include <sys/conf.h>
- #include <sys/disklabel.h>
- #include <sys/filio.h>
- #include <sys/time.h>
- #include <ctype.h>
- #include <err.h>
- #include <errno.h>
- #include <fcntl.h>
- #include <inttypes.h>
- #include <locale.h>
- #include <stdio.h>
- #include <stdlib.h>
- #include <string.h>
- #include <unistd.h>
- #include "dd.h"
- #include "extern.h"
- static void dd_close(void);
- static void dd_in(void);
- static void getfdtype(IO *);
- static void setup(void);
- IO in, out; /* input/output state */
- STAT st; /* statistics */
- void (*cfunc)(void); /* conversion function */
- uintmax_t cpy_cnt; /* # of blocks to copy */
- static off_t pending = 0; /* pending seek if sparse */
- u_int ddflags = 0; /* conversion options */
- size_t cbsz; /* conversion block size */
- uintmax_t files_cnt = 1; /* # of files to copy */
- const u_char *ctab; /* conversion table */
- char fill_char; /* Character to fill with if defined */
- int
- main(int argc __unused, char *argv[])
- {
- (void)setlocale(LC_CTYPE, "");
- jcl(argv);
- setup();
- (void)signal(SIGINFO, summaryx);
- (void)signal(SIGINT, terminate);
- atexit(summary);
- while (files_cnt--)
- dd_in();
- dd_close();
- exit(0);
- }
- static int
- parity(u_char c)
- {
- int i;
- i = c ^ (c >> 1) ^ (c >> 2) ^ (c >> 3) ^
- (c >> 4) ^ (c >> 5) ^ (c >> 6) ^ (c >> 7);
- return (i & 1);
- }
- static void
- setup(void)
- {
- u_int cnt;
- struct timeval tv;
- if (in.name == NULL) {
- in.name = "stdin";
- in.fd = STDIN_FILENO;
- } else {
- in.fd = open(in.name, O_RDONLY, 0);
- if (in.fd == -1)
- err(1, "%s", in.name);
- }
- getfdtype(&in);
- if (files_cnt > 1 && !(in.flags & ISTAPE))
- errx(1, "files is not supported for non-tape devices");
- if (out.name == NULL) {
- /* No way to check for read access here. */
- out.fd = STDOUT_FILENO;
- out.name = "stdout";
- } else {
- #define OFLAGS \
- (O_CREAT | (ddflags & (C_SEEK | C_NOTRUNC) ? 0 : O_TRUNC))
- out.fd = open(out.name, O_RDWR | OFLAGS, DEFFILEMODE);
- /*
- * May not have read access, so try again with write only.
- * Without read we may have a problem if output also does
- * not support seeks.
- */
- if (out.fd == -1) {
- out.fd = open(out.name, O_WRONLY | OFLAGS, DEFFILEMODE);
- out.flags |= NOREAD;
- }
- if (out.fd == -1)
- err(1, "%s", out.name);
- }
- getfdtype(&out);
- /*
- * Allocate space for the input and output buffers. If not doing
- * record oriented I/O, only need a single buffer.
- */
- if (!(ddflags & (C_BLOCK | C_UNBLOCK))) {
- if ((in.db = malloc(out.dbsz + in.dbsz - 1)) == NULL)
- err(1, "input buffer");
- out.db = in.db;
- } else if ((in.db = malloc(MAX(in.dbsz, cbsz) + cbsz)) == NULL ||
- (out.db = malloc(out.dbsz + cbsz)) == NULL)
- err(1, "output buffer");
- in.dbp = in.db;
- out.dbp = out.db;
- /* Position the input/output streams. */
- if (in.offset)
- pos_in();
- if (out.offset)
- pos_out();
- /*
- * Truncate the output file. If it fails on a type of output file
- * that it should _not_ fail on, error out.
- */
- if ((ddflags & (C_OF | C_SEEK | C_NOTRUNC)) == (C_OF | C_SEEK) &&
- out.flags & ISTRUNC)
- if (ftruncate(out.fd, out.offset * out.dbsz) == -1)
- err(1, "truncating %s", out.name);
- if (ddflags & (C_LCASE | C_UCASE | C_ASCII | C_EBCDIC | C_PARITY)) {
- if (ctab != NULL) {
- for (cnt = 0; cnt <= 0377; ++cnt)
- casetab[cnt] = ctab[cnt];
- } else {
- for (cnt = 0; cnt <= 0377; ++cnt)
- casetab[cnt] = cnt;
- }
- if ((ddflags & C_PARITY) && !(ddflags & C_ASCII)) {
- /*
- * If the input is not EBCDIC, and we do parity
- * processing, strip input parity.
- */
- for (cnt = 200; cnt <= 0377; ++cnt)
- casetab[cnt] = casetab[cnt & 0x7f];
- }
- if (ddflags & C_LCASE) {
- for (cnt = 0; cnt <= 0377; ++cnt)
- casetab[cnt] = tolower(casetab[cnt]);
- } else if (ddflags & C_UCASE) {
- for (cnt = 0; cnt <= 0377; ++cnt)
- casetab[cnt] = toupper(casetab[cnt]);
- }
- if ((ddflags & C_PARITY)) {
- /*
- * This should strictly speaking be a no-op, but I
- * wonder what funny LANG settings could get us.
- */
- for (cnt = 0; cnt <= 0377; ++cnt)
- casetab[cnt] = casetab[cnt] & 0x7f;
- }
- if ((ddflags & C_PARSET)) {
- for (cnt = 0; cnt <= 0377; ++cnt)
- casetab[cnt] = casetab[cnt] | 0x80;
- }
- if ((ddflags & C_PAREVEN)) {
- for (cnt = 0; cnt <= 0377; ++cnt)
- if (parity(casetab[cnt]))
- casetab[cnt] = casetab[cnt] | 0x80;
- }
- if ((ddflags & C_PARODD)) {
- for (cnt = 0; cnt <= 0377; ++cnt)
- if (!parity(casetab[cnt]))
- casetab[cnt] = casetab[cnt] | 0x80;
- }
- ctab = casetab;
- }
- (void)gettimeofday(&tv, NULL);
- st.start = tv.tv_sec + tv.tv_usec * 1e-6;
- }
- static void
- getfdtype(IO *io)
- {
- struct stat sb;
- int type;
- if (fstat(io->fd, &sb) == -1)
- err(1, "%s", io->name);
- if (S_ISREG(sb.st_mode))
- io->flags |= ISTRUNC;
- if (S_ISCHR(sb.st_mode) || S_ISBLK(sb.st_mode)) {
- if (ioctl(io->fd, FIODTYPE, &type) == -1) {
- err(1, "%s", io->name);
- } else {
- if (type & D_TAPE)
- io->flags |= ISTAPE;
- else if (type & (D_DISK | D_MEM))
- io->flags |= ISSEEK;
- if (S_ISCHR(sb.st_mode) && (type & D_TAPE) == 0)
- io->flags |= ISCHR;
- }
- return;
- }
- errno = 0;
- if (lseek(io->fd, (off_t)0, SEEK_CUR) == -1 && errno == ESPIPE)
- io->flags |= ISPIPE;
- else
- io->flags |= ISSEEK;
- }
- static void
- dd_in(void)
- {
- ssize_t n;
- for (;;) {
- switch (cpy_cnt) {
- case -1: /* count=0 was specified */
- return;
- case 0:
- break;
- default:
- if (st.in_full + st.in_part >= (uintmax_t)cpy_cnt)
- return;
- break;
- }
- /*
- * Zero the buffer first if sync; if doing block operations,
- * use spaces.
- */
- if (ddflags & C_SYNC) {
- if (ddflags & C_FILL)
- memset(in.dbp, fill_char, in.dbsz);
- else if (ddflags & (C_BLOCK | C_UNBLOCK))
- memset(in.dbp, ' ', in.dbsz);
- else
- memset(in.dbp, 0, in.dbsz);
- }
- n = read(in.fd, in.dbp, in.dbsz);
- if (n == 0) {
- in.dbrcnt = 0;
- return;
- }
- /* Read error. */
- if (n == -1) {
- /*
- * If noerror not specified, die. POSIX requires that
- * the warning message be followed by an I/O display.
- */
- if (!(ddflags & C_NOERROR))
- err(1, "%s", in.name);
- warn("%s", in.name);
- summary();
- /*
- * If it's a seekable file descriptor, seek past the
- * error. If your OS doesn't do the right thing for
- * raw disks this section should be modified to re-read
- * in sector size chunks.
- */
- if (in.flags & ISSEEK &&
- lseek(in.fd, (off_t)in.dbsz, SEEK_CUR))
- warn("%s", in.name);
- /* If sync not specified, omit block and continue. */
- if (!(ddflags & C_SYNC))
- continue;
- /* Read errors count as full blocks. */
- in.dbcnt += in.dbrcnt = in.dbsz;
- ++st.in_full;
- /* Handle full input blocks. */
- } else if ((size_t)n == in.dbsz) {
- in.dbcnt += in.dbrcnt = n;
- ++st.in_full;
- /* Handle partial input blocks. */
- } else {
- /* If sync, use the entire block. */
- if (ddflags & C_SYNC)
- in.dbcnt += in.dbrcnt = in.dbsz;
- else
- in.dbcnt += in.dbrcnt = n;
- ++st.in_part;
- }
- /*
- * POSIX states that if bs is set and no other conversions
- * than noerror, notrunc or sync are specified, the block
- * is output without buffering as it is read.
- */
- if (ddflags & C_BS) {
- out.dbcnt = in.dbcnt;
- dd_out(1);
- in.dbcnt = 0;
- continue;
- }
- if (ddflags & C_SWAB) {
- if ((n = in.dbrcnt) & 1) {
- ++st.swab;
- --n;
- }
- swab(in.dbp, in.dbp, (size_t)n);
- }
- in.dbp += in.dbrcnt;
- (*cfunc)();
- }
- }
- /*
- * Clean up any remaining I/O and flush output. If necessary, the output file
- * is truncated.
- */
- static void
- dd_close(void)
- {
- if (cfunc == def)
- def_close();
- else if (cfunc == block)
- block_close();
- else if (cfunc == unblock)
- unblock_close();
- if (ddflags & C_OSYNC && out.dbcnt && out.dbcnt < out.dbsz) {
- if (ddflags & C_FILL)
- memset(out.dbp, fill_char, out.dbsz - out.dbcnt);
- else if (ddflags & (C_BLOCK | C_UNBLOCK))
- memset(out.dbp, ' ', out.dbsz - out.dbcnt);
- else
- memset(out.dbp, 0, out.dbsz - out.dbcnt);
- out.dbcnt = out.dbsz;
- }
- if (out.dbcnt || pending)
- dd_out(1);
- }
- void
- dd_out(int force)
- {
- u_char *outp;
- size_t cnt, i, n;
- ssize_t nw;
- static int warned;
- int sparse;
- /*
- * Write one or more blocks out. The common case is writing a full
- * output block in a single write; increment the full block stats.
- * Otherwise, we're into partial block writes. If a partial write,
- * and it's a character device, just warn. If a tape device, quit.
- *
- * The partial writes represent two cases. 1: Where the input block
- * was less than expected so the output block was less than expected.
- * 2: Where the input block was the right size but we were forced to
- * write the block in multiple chunks. The original versions of dd(1)
- * never wrote a block in more than a single write, so the latter case
- * never happened.
- *
- * One special case is if we're forced to do the write -- in that case
- * we play games with the buffer size, and it's usually a partial write.
- */
- outp = out.db;
- for (n = force ? out.dbcnt : out.dbsz;; n = out.dbsz) {
- for (cnt = n;; cnt -= nw) {
- sparse = 0;
- if (ddflags & C_SPARSE) {
- sparse = 1; /* Is buffer sparse? */
- for (i = 0; i < cnt; i++)
- if (outp[i] != 0) {
- sparse = 0;
- break;
- }
- }
- if (sparse && !force) {
- pending += cnt;
- nw = cnt;
- } else {
- if (pending != 0) {
- if (force)
- pending--;
- if (lseek(out.fd, pending, SEEK_CUR) ==
- -1)
- err(2, "%s: seek error creating sparse file",
- out.name);
- if (force)
- write(out.fd, outp, 1);
- pending = 0;
- }
- if (cnt)
- nw = write(out.fd, outp, cnt);
- else
- return;
- }
- if (nw <= 0) {
- if (nw == 0)
- errx(1, "%s: end of device", out.name);
- if (errno != EINTR)
- err(1, "%s", out.name);
- nw = 0;
- }
- outp += nw;
- st.bytes += nw;
- if ((size_t)nw == n) {
- if (n != out.dbsz)
- ++st.out_part;
- else
- ++st.out_full;
- break;
- }
- ++st.out_part;
- if ((size_t)nw == cnt)
- break;
- if (out.flags & ISTAPE)
- errx(1, "%s: short write on tape device",
- out.name);
- if (out.flags & ISCHR && !warned) {
- warned = 1;
- warnx("%s: short write on character device",
- out.name);
- }
- }
- if ((out.dbcnt -= n) < out.dbsz)
- break;
- }
- /* Reassemble the output block. */
- if (out.dbcnt)
- (void)memmove(out.db, out.dbp - out.dbcnt, out.dbcnt);
- out.dbp = out.db + out.dbcnt;
- }