* Mini dd implementation for busybox
*
*
- * Copyright (C) 2000 by Matt Kraai <kraai@alumni.carnegiemellon.edu>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ * Copyright (C) 2000,2001 Matt Kraai
*
+ * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
*/
-#include "busybox.h"
-
#include <sys/types.h>
+#include <sys/stat.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <string.h>
#include <fcntl.h>
+#include <signal.h> // For FEATURE_DD_SIGNAL_HANDLING
+#include "busybox.h"
-static struct suffix_mult dd_suffixes[] = {
+static const struct suffix_mult dd_suffixes[] = {
{ "c", 1 },
{ "w", 2 },
{ "b", 512 },
{ NULL, 0 }
};
+static size_t out_full;
+static size_t out_part;
+static size_t in_full;
+static size_t in_part;
+
+static void dd_output_status(int cur_signal)
+{
+ fprintf(stderr, "%ld+%ld records in\n%ld+%ld records out\n",
+ (long)in_full, (long)in_part,
+ (long)out_full, (long)out_part);
+}
+
int dd_main(int argc, char **argv)
{
- int i, ifd, ofd, oflag, sync = FALSE, trunc = TRUE;
- size_t in_full = 0, in_part = 0, out_full = 0, out_part = 0;
- size_t bs = 512, count = -1;
+ size_t count = -1, oc = 0, ibs = 512, obs = 512;
ssize_t n;
off_t seek = 0, skip = 0;
- FILE *statusfp;
- char *infile = NULL, *outfile = NULL, *buf;
+ int sync_flag = FALSE, noerror = FALSE, trunc_flag = TRUE, twobufs_flag = 0,
+ oflag, ifd, ofd, i;
+ const char *infile = NULL, *outfile = NULL;
+ char *ibuf, *obuf;
+
+ if (ENABLE_FEATURE_DD_SIGNAL_HANDLING)
+ {
+ struct sigaction sa;
+
+ memset(&sa, 0, sizeof(sa));
+ sa.sa_handler = dd_output_status;
+ sa.sa_flags = SA_RESTART;
+ sigemptyset(&sa.sa_mask);
+ sigaction(SIGUSR1, &sa, 0);
+ }
for (i = 1; i < argc; i++) {
- if (strncmp("bs=", argv[i], 3) == 0)
- bs = parse_number(argv[i]+3, dd_suffixes);
- else if (strncmp("count=", argv[i], 6) == 0)
- count = parse_number(argv[i]+6, dd_suffixes);
- else if (strncmp("seek=", argv[i], 5) == 0)
- seek = parse_number(argv[i]+5, dd_suffixes);
- else if (strncmp("skip=", argv[i], 5) == 0)
- skip = parse_number(argv[i]+5, dd_suffixes);
- else if (strncmp("if=", argv[i], 3) == 0)
+ if (ENABLE_FEATURE_DD_IBS_OBS && !strncmp("ibs=", argv[i], 4)) {
+ ibs = bb_xparse_number(argv[i]+4, dd_suffixes);
+ twobufs_flag++;
+ } else if (ENABLE_FEATURE_DD_IBS_OBS && !strncmp("obs=", argv[i], 4)) {
+ obs = bb_xparse_number(argv[i]+4, dd_suffixes);
+ twobufs_flag++;
+ } else if (!strncmp("bs=", argv[i], 3)) {
+ ibs = obs = bb_xparse_number(argv[i]+3, dd_suffixes);
+ } else if (!strncmp("count=", argv[i], 6))
+ count = bb_xparse_number(argv[i]+6, dd_suffixes);
+ else if (!strncmp("seek=", argv[i], 5))
+ seek = bb_xparse_number(argv[i]+5, dd_suffixes);
+ else if (!strncmp("skip=", argv[i], 5))
+ skip = bb_xparse_number(argv[i]+5, dd_suffixes);
+ else if (!strncmp("if=", argv[i], 3))
infile = argv[i]+3;
- else if (strncmp("of=", argv[i], 3) == 0)
+ else if (!strncmp("of=", argv[i], 3))
outfile = argv[i]+3;
- else if (strncmp("conv=", argv[i], 5) == 0) {
- buf = argv[i]+5;
+ else if (ENABLE_FEATURE_DD_IBS_OBS && !strncmp("conv=", argv[i], 5)) {
+ ibuf = argv[i]+5;
while (1) {
- if (strncmp("notrunc", buf, 7) == 0) {
- trunc = FALSE;
- buf += 7;
- } else if (strncmp("sync", buf, 4) == 0) {
- sync = TRUE;
- buf += 4;
+ if (!strncmp("notrunc", ibuf, 7)) {
+ trunc_flag = FALSE;
+ ibuf += 7;
+ } else if (!strncmp("sync", ibuf, 4)) {
+ sync_flag = TRUE;
+ ibuf += 4;
+ } else if (!strncmp("noerror", ibuf, 7)) {
+ noerror = TRUE;
+ ibuf += 7;
} else {
- error_msg_and_die("invalid conversion `%s'\n", argv[i]+5);
+ bb_error_msg_and_die("invalid conversion `%s'", argv[i]+5);
}
- if (buf[0] == '\0')
- break;
- if (buf[0] == ',')
- buf++;
+ if (ibuf[0] == '\0') break;
+ if (ibuf[0] == ',') ibuf++;
}
} else
- usage(dd_usage);
+ bb_show_usage();
}
+ ibuf = xmalloc(ibs);
- buf = xmalloc(bs);
+ if (twobufs_flag) obuf = xmalloc(obs);
+ else obuf = ibuf;
if (infile != NULL) {
- if ((ifd = open(infile, O_RDONLY)) < 0)
- perror_msg_and_die("%s", infile);
+ ifd = bb_xopen(infile, O_RDONLY);
} else {
ifd = STDIN_FILENO;
- infile = "standard input";
+ infile = bb_msg_standard_input;
}
if (outfile != NULL) {
oflag = O_WRONLY | O_CREAT;
- if (!seek && trunc)
+ if (!seek && trunc_flag) {
oflag |= O_TRUNC;
+ }
- if ((ofd = open(outfile, oflag, 0666)) < 0)
- perror_msg_and_die("%s", outfile);
+ ofd = bb_xopen3(outfile, oflag, 0666);
- if (seek && trunc) {
- if (ftruncate(ofd, seek * bs) < 0)
- perror_msg_and_die("%s", outfile);
- }
+ if (seek && trunc_flag) {
+ if (ftruncate(ofd, seek * obs) < 0) {
+ struct stat st;
- statusfp = stdout;
+ if (fstat (ofd, &st) < 0 || S_ISREG (st.st_mode) ||
+ S_ISDIR (st.st_mode)) {
+ bb_perror_msg_and_die("%s", outfile);
+ }
+ }
+ }
} else {
ofd = STDOUT_FILENO;
- outfile = "standard output";
- statusfp = stderr;
+ outfile = bb_msg_standard_output;
}
if (skip) {
- if (lseek(ifd, skip * bs, SEEK_CUR) < 0)
- perror_msg_and_die("%s", infile);
+ if (lseek(ifd, skip * ibs, SEEK_CUR) < 0) {
+ while (skip-- > 0) {
+ n = safe_read(ifd, ibuf, ibs);
+ if (n < 0)
+ bb_perror_msg_and_die("%s", infile);
+ if (n == 0)
+ break;
+ }
+ }
}
if (seek) {
- if (lseek(ofd, seek * bs, SEEK_CUR) < 0)
- perror_msg_and_die("%s", outfile);
+ if (lseek(ofd, seek * obs, SEEK_CUR) < 0) {
+ bb_perror_msg_and_die("%s", outfile);
+ }
}
while (in_full + in_part != count) {
- n = safe_read(ifd, buf, bs);
- if (n < 0)
- perror_msg_and_die("%s", infile);
- if (n == 0)
+ if (noerror) {
+ /* Pre-zero the buffer when doing the noerror thing */
+ memset(ibuf, '\0', ibs);
+ }
+
+ n = safe_read(ifd, ibuf, ibs);
+ if (n == 0) {
break;
- if (n == bs)
+ }
+ if (n < 0) {
+ if (noerror) {
+ n = ibs;
+ bb_perror_msg("%s", infile);
+ } else {
+ bb_perror_msg_and_die("%s", infile);
+ }
+ }
+ if ((size_t)n == ibs) {
in_full++;
- else
+ } else {
in_part++;
- if (sync) {
- memset(buf + n, '\0', bs - n);
- n = bs;
+ if (sync_flag) {
+ memset(ibuf + n, '\0', ibs - n);
+ n = ibs;
+ }
}
- n = full_write(ofd, buf, n);
- if (n < 0)
- perror_msg_and_die("%s", outfile);
- if (n == bs)
- out_full++;
- else
- out_part++;
+ if (twobufs_flag) {
+ char *tmp = ibuf;
+ while (n) {
+ size_t d = obs - oc;
+
+ if (d > n) d = n;
+ memcpy(obuf + oc, tmp, d);
+ n -= d;
+ tmp += d;
+ oc += d;
+ if (oc == obs) {
+ if (bb_full_write(ofd, obuf, obs) < 0) {
+ bb_perror_msg_and_die("%s", outfile);
+ }
+ out_full++;
+ oc = 0;
+ }
+ }
+ } else {
+ if ((n = bb_full_write(ofd, ibuf, n)) < 0) {
+ bb_perror_msg_and_die("%s", outfile);
+ }
+ if (n == ibs) out_full++;
+ else out_part++;
+ }
+ }
+
+ if (ENABLE_FEATURE_DD_IBS_OBS && oc) {
+ if (bb_full_write(ofd, obuf, oc) < 0) {
+ bb_perror_msg_and_die("%s", outfile);
+ }
+ out_part++;
+ }
+ if (close (ifd) < 0) {
+ bb_perror_msg_and_die("%s", infile);
+ }
+
+ if (close (ofd) < 0) {
+ bb_perror_msg_and_die("%s", outfile);
}
- fprintf(statusfp, "%d+%d records in\n", in_full, in_part);
- fprintf(statusfp, "%d+%d records out\n", out_full, out_part);
+ dd_output_status(0);
return EXIT_SUCCESS;
}