diff options
Diffstat (limited to 'bin/dd/dd.c')
-rw-r--r-- | bin/dd/dd.c | 395 |
1 files changed, 395 insertions, 0 deletions
diff --git a/bin/dd/dd.c b/bin/dd/dd.c new file mode 100644 index 0000000..05ac7a9 --- /dev/null +++ b/bin/dd/dd.c @@ -0,0 +1,395 @@ +/*- + * 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; +} |