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-rw-r--r--bin/dd/dd.c395
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diff --git a/bin/dd/dd.c b/bin/dd/dd.c
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+++ b/bin/dd/dd.c
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+/*-
+ * 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.
+ * 3. All advertising materials mentioning features or use of this software
+ * must display the following acknowledgement:
+ * This product includes software developed by the University of
+ * California, Berkeley and its contributors.
+ * 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.
+ */
+
+#ifndef lint
+static char 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 */
+
+#include <sys/param.h>
+#include <sys/stat.h>
+#include <sys/ioctl.h>
+#include <sys/mtio.h>
+
+#include <ctype.h>
+#include <err.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "dd.h"
+#include "extern.h"
+
+static void dd_close __P((void));
+static void dd_in __P((void));
+static void getfdtype __P((IO *));
+static void setup __P((void));
+
+IO in, out; /* input/output state */
+STAT st; /* statistics */
+void (*cfunc) __P((void)); /* conversion function */
+u_long cpy_cnt; /* # of blocks to copy */
+u_int ddflags; /* conversion options */
+u_int cbsz; /* conversion block size */
+u_int files_cnt = 1; /* # of files to copy */
+u_char *ctab; /* conversion table */
+
+int
+main(argc, argv)
+ int argc;
+ char *argv[];
+{
+ jcl(argv);
+ setup();
+
+ (void)signal(SIGINFO, summaryx);
+ (void)signal(SIGINT, terminate);
+
+ atexit(summary);
+
+ while (files_cnt--)
+ dd_in();
+
+ dd_close();
+ exit(0);
+}
+
+static void
+setup()
+{
+ u_int cnt;
+
+ if (in.name == NULL) {
+ in.name = "stdin";
+ in.fd = STDIN_FILENO;
+ } else {
+ in.fd = open(in.name, O_RDONLY, 0);
+ if (in.fd < 0)
+ 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 < 0) {
+ out.fd = open(out.name, O_WRONLY | OFLAGS, DEFFILEMODE);
+ out.flags |= NOREAD;
+ }
+ if (out.fd < 0)
+ 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, NULL);
+ out.db = in.db;
+ } else if ((in.db =
+ malloc((u_int)(MAX(in.dbsz, cbsz) + cbsz))) == NULL ||
+ (out.db = malloc((u_int)(out.dbsz + cbsz))) == NULL)
+ err(1, NULL);
+ 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; ignore errors because it fails on some
+ * kinds of output files, tapes, for example.
+ */
+ if (ddflags & (C_OF | C_SEEK | C_NOTRUNC) == (C_OF | C_SEEK))
+ (void)ftruncate(out.fd, (off_t)out.offset * out.dbsz);
+
+ /*
+ * If converting case at the same time as another conversion, build a
+ * table that does both at once. If just converting case, use the
+ * built-in tables.
+ */
+ if (ddflags & (C_LCASE|C_UCASE))
+ if (ddflags & C_ASCII)
+ if (ddflags & C_LCASE) {
+ for (cnt = 0; cnt < 0377; ++cnt)
+ if (isupper(ctab[cnt]))
+ ctab[cnt] = tolower(ctab[cnt]);
+ } else {
+ for (cnt = 0; cnt < 0377; ++cnt)
+ if (islower(ctab[cnt]))
+ ctab[cnt] = toupper(ctab[cnt]);
+ }
+ else if (ddflags & C_EBCDIC)
+ if (ddflags & C_LCASE) {
+ for (cnt = 0; cnt < 0377; ++cnt)
+ if (isupper(cnt))
+ ctab[cnt] = ctab[tolower(cnt)];
+ } else {
+ for (cnt = 0; cnt < 0377; ++cnt)
+ if (islower(cnt))
+ ctab[cnt] = ctab[toupper(cnt)];
+ }
+ else
+ ctab = ddflags & C_LCASE ? u2l : l2u;
+ (void)time(&st.start); /* Statistics timestamp. */
+}
+
+static void
+getfdtype(io)
+ IO *io;
+{
+ struct mtget mt;
+ struct stat sb;
+
+ if (fstat(io->fd, &sb))
+ err(1, "%s", io->name);
+ if (S_ISCHR(sb.st_mode))
+ io->flags |= ioctl(io->fd, MTIOCGET, &mt) ? ISCHR : ISTAPE;
+ else if (lseek(io->fd, (off_t)0, SEEK_CUR) == -1 && errno == ESPIPE)
+ io->flags |= ISPIPE; /* XXX fixed in 4.4BSD */
+}
+
+static void
+dd_in()
+{
+ int flags, n;
+
+ for (flags = ddflags;;) {
+ if (cpy_cnt && (st.in_full + st.in_part) >= cpy_cnt)
+ return;
+
+ /*
+ * Zero the buffer first if trying to recover from errors so
+ * lose the minimum amount of data. If doing block operations
+ * use spaces.
+ */
+ if ((flags & (C_NOERROR|C_SYNC)) == (C_NOERROR|C_SYNC))
+ if (flags & (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 < 0) {
+ /*
+ * If noerror not specified, die. POSIX requires that
+ * the warning message be followed by an I/O display.
+ */
+ if (!(flags & C_NOERROR))
+ err(1, "%s", in.name);
+ warn("%s", in.name);
+ summary();
+
+ /*
+ * If it's not a tape drive or a pipe, 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 & (ISPIPE|ISTAPE)) &&
+ 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 (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.dbcnt) & 1) {
+ ++st.swab;
+ --n;
+ }
+ swab(in.dbp, in.dbp, n);
+ }
+
+ in.dbp += in.dbrcnt;
+ (*cfunc)();
+ }
+}
+
+/*
+ * Cleanup any remaining I/O and flush output. If necesssary, output file
+ * is truncated.
+ */
+static void
+dd_close()
+{
+ if (cfunc == def)
+ def_close();
+ else if (cfunc == block)
+ block_close();
+ else if (cfunc == unblock)
+ unblock_close();
+ if (ddflags & C_OSYNC && out.dbcnt < out.dbsz) {
+ memset(out.dbp, 0, out.dbsz - out.dbcnt);
+ out.dbcnt = out.dbsz;
+ }
+ if (out.dbcnt)
+ dd_out(1);
+}
+
+void
+dd_out(force)
+ int force;
+{
+ static int warned;
+ int cnt, n, nw;
+ u_char *outp;
+
+ /*
+ * 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) {
+ nw = write(out.fd, outp, cnt);
+ 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 (nw == n) {
+ if (n != out.dbsz)
+ ++st.out_part;
+ else
+ ++st.out_full;
+ break;
+ }
+ ++st.out_part;
+ if (nw == cnt)
+ break;
+ if (out.flags & ISCHR && !warned) {
+ warned = 1;
+ warnx("%s: short write on character device",
+ out.name);
+ }
+ if (out.flags & ISTAPE)
+ errx(1, "%s: short write on tape device", out.name);
+ }
+ if ((out.dbcnt -= n) < out.dbsz)
+ break;
+ }
+
+ /* Reassemble the output block. */
+ if (out.dbcnt)
+ memmove(out.db, out.dbp - out.dbcnt, out.dbcnt);
+ out.dbp = out.db + out.dbcnt;
+}
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