/* $OpenBSD: dd.c,v 1.8 1998/04/30 05:55:02 deraadt Exp $ */ /* $NetBSD: dd.c,v 1.6 1996/02/20 19:29:06 jtc Exp $ */ /*- * 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 #if 0 static char sccsid[] = "@(#)dd.c 8.5 (Berkeley) 4/2/94"; #else static char rcsid[] = "$OpenBSD: dd.c,v 1.8 1998/04/30 05:55:02 deraadt Exp $"; #endif #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 */ size_t cpy_cnt; /* # of blocks to copy */ u_int ddflags; /* conversion options */ size_t cbsz; /* conversion block size */ size_t files_cnt = 1; /* # of files to copy */ const 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, "input buffer"); 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, "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; 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, 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)) { #ifdef NO_CONV /* Should not get here, but just in case... */ errx(1, "case conv and -DNO_CONV"); #else /* NO_CONV */ if (ddflags & C_ASCII || ddflags & C_EBCDIC) { if (ddflags & C_LCASE) { for (cnt = 0; cnt < 0377; ++cnt) casetab[cnt] = tolower(ctab[cnt]); } else { for (cnt = 0; cnt < 0377; ++cnt) casetab[cnt] = toupper(ctab[cnt]); } } else { if (ddflags & C_LCASE) { for (cnt = 0; cnt < 0377; ++cnt) casetab[cnt] = tolower(cnt); } else { for (cnt = 0; cnt < 0377; ++cnt) casetab[cnt] = toupper(cnt); } } ctab = casetab; #endif /* NO_CONV */ } (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() { ssize_t n; for (;;) { if (cpy_cnt && (st.in_full + st.in_part) >= cpy_cnt) return; /* * Zero the buffer first if sync; if doing block operations * use spaces. */ if (ddflags & C_SYNC) { if (ddflags & (C_BLOCK|C_UNBLOCK)) (void)memset(in.dbp, ' ', in.dbsz); else (void)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 (!(ddflags & 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 necessary, 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.dbcnt < out.dbsz) { 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) dd_out(1); } void dd_out(force) int force; { static int warned; size_t cnt, n; ssize_t 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) (void)memmove(out.db, out.dbp - out.dbcnt, out.dbcnt); out.dbp = out.db + out.dbcnt; }