* 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 <sys/types.h>
-#include <stdlib.h>
-#include <stdio.h>
-#include <unistd.h>
-#include <string.h>
-#include <fcntl.h>
#include "busybox.h"
-
+#include <signal.h> /* For FEATURE_DD_SIGNAL_HANDLING */
static const struct suffix_mult dd_suffixes[] = {
{ "c", 1 },
{ "b", 512 },
{ "kD", 1000 },
{ "k", 1024 },
+ { "K", 1024 }, /* compat with coreutils dd */
{ "MD", 1000000 },
{ "M", 1048576 },
{ "GD", 1000000000 },
{ NULL, 0 }
};
+struct globals {
+ off_t out_full, out_part, in_full, in_part;
+};
+#define G (*(struct globals*)&bb_common_bufsiz1)
+
+static void dd_output_status(int ATTRIBUTE_UNUSED cur_signal)
+{
+ fprintf(stderr, "%"OFF_FMT"d+%"OFF_FMT"d records in\n"
+ "%"OFF_FMT"d+%"OFF_FMT"d records out\n",
+ G.in_full, G.in_part,
+ G.out_full, G.out_part);
+}
+
+static ssize_t full_write_or_warn(int fd, const void *buf, size_t len,
+ const char * const filename)
+{
+ ssize_t n = full_write(fd, buf, len);
+ if (n < 0)
+ bb_perror_msg("writing '%s'", filename);
+ return n;
+}
+
+static bool write_and_stats(int fd, const void *buf, size_t len, size_t obs,
+ const char * const filename)
+{
+ ssize_t n = full_write_or_warn(fd, buf, len, filename);
+ if (n < 0)
+ return 1;
+ if (n == obs)
+ G.out_full++;
+ else if (n > 0)
+ G.out_part++;
+ return 0;
+}
+
+#if ENABLE_LFS
+#define XATOU_SFX xatoull_sfx
+#else
+#define XATOU_SFX xatoul_sfx
+#endif
+
+int dd_main(int argc, char **argv);
int dd_main(int argc, char **argv)
{
- int i, ifd, ofd, oflag, sync_flag = FALSE, trunc = TRUE;
- size_t in_full = 0, in_part = 0, out_full = 0, out_part = 0;
- size_t bs = 512, count = -1;
- ssize_t n;
- off_t seek = 0, skip = 0;
- FILE *statusfp;
- char *infile = NULL, *outfile = NULL, *buf;
-
- 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)
- infile = argv[i]+3;
- else if (strncmp("of=", argv[i], 3) == 0)
- outfile = argv[i]+3;
- else if (strncmp("conv=", argv[i], 5) == 0) {
- buf = argv[i]+5;
- while (1) {
- if (strncmp("notrunc", buf, 7) == 0) {
- trunc = FALSE;
- buf += 7;
- } else if (strncmp("sync", buf, 4) == 0) {
- sync_flag = TRUE;
- buf += 4;
- } else {
- error_msg_and_die("invalid conversion `%s'", argv[i]+5);
- }
- if (buf[0] == '\0')
- break;
- if (buf[0] == ',')
- buf++;
- }
- } else
- show_usage();
+ enum {
+ sync_flag = 1 << 0,
+ noerror = 1 << 1,
+ trunc_flag = 1 << 2,
+ twobufs_flag = 1 << 3,
+ };
+ const char * const keywords[] = {
+ "bs=", "count=", "seek=", "skip=", "if=", "of=",
+#if ENABLE_FEATURE_DD_IBS_OBS
+ "ibs=", "obs=", "conv=", "notrunc", "sync", "noerror",
+#endif
+ NULL
+ };
+#define OP_bs 0 + 1
+#define OP_count OP_bs + 1
+#define OP_seek OP_count + 1
+#define OP_skip OP_seek + 1
+#define OP_if OP_skip + 1
+#define OP_of OP_if + 1
+#define OP_ibs OP_of + ENABLE_FEATURE_DD_IBS_OBS
+#define OP_obs OP_ibs + ENABLE_FEATURE_DD_IBS_OBS
+#define OP_conv OP_obs + ENABLE_FEATURE_DD_IBS_OBS
+#define OP_conv_notrunc OP_conv + ENABLE_FEATURE_DD_IBS_OBS
+#define OP_conv_sync OP_conv_notrunc + ENABLE_FEATURE_DD_IBS_OBS
+#define OP_conv_noerror OP_conv_sync + ENABLE_FEATURE_DD_IBS_OBS
+
+ int flags = trunc_flag;
+ size_t oc = 0, ibs = 512, obs = 512;
+ ssize_t n, w;
+ off_t seek = 0, skip = 0, count = OFF_T_MAX;
+ int ifd, ofd;
+ 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);
}
- buf = xmalloc(bs);
+ for (n = 1; n < argc; n++) {
+ smalluint key_len, what;
+ char *key;
+ char *arg = argv[n];
- if (infile != NULL) {
- if ((ifd = open(infile, O_RDONLY)) < 0)
- perror_msg_and_die("%s", infile);
- } else {
+//XXX:FIXME: we reject plain "dd --" This would cost ~20 bytes, so..
+//if (*arg == '-' && *++arg == '-' && !*++arg) continue;
+ key = strstr(arg, "=");
+ if (key == NULL)
+ bb_show_usage();
+ key_len = key - arg + 1;
+ key = xstrndup(arg, key_len);
+ what = index_in_str_array(keywords, key) + 1;
+ if (ENABLE_FEATURE_CLEAN_UP)
+ free(key);
+ if (what == 0)
+ bb_show_usage();
+ arg += key_len;
+ /* Must fit into positive ssize_t */
+ if (ENABLE_FEATURE_DD_IBS_OBS) {
+ if (what == OP_ibs) {
+ ibs = xatoul_range_sfx(arg, 1, ((size_t)-1L)/2, dd_suffixes);
+ continue;
+ }
+ if (what == OP_obs) {
+ obs = xatoul_range_sfx(arg, 1, ((size_t)-1L)/2, dd_suffixes);
+ continue;
+ }
+ if (what == OP_conv) {
+ while (1) {
+ /* find ',', replace them with nil so we can use arg for
+ * index_in_str_array without copying.
+ * We rely on arg being non-null, else strstr would fault.
+ */
+ key = strstr(arg, ",");
+ if (key)
+ *key = '\0';
+ what = index_in_str_array(keywords, arg) + 1;
+ if (what < OP_conv_notrunc)
+ bb_error_msg_and_die(bb_msg_invalid_arg, arg, "conv");
+ if (what == OP_conv_notrunc)
+ flags &= ~trunc_flag;
+ if (what == OP_conv_sync)
+ flags |= sync_flag;
+ if (what == OP_conv_noerror)
+ flags |= noerror;
+ if (!key) /* no ',' left, so this was the last specifier */
+ break;
+ arg += key - arg + 1; /* skip this keyword plus ',' */
+ }
+ continue;
+ }
+ }
+ if (what == OP_bs) {
+ ibs = obs = xatoul_range_sfx(arg, 1, ((size_t)-1L)/2, dd_suffixes);
+ continue;
+ }
+ /* These can be large: */
+ if (what == OP_count) {
+ count = XATOU_SFX(arg, dd_suffixes);
+ continue;
+ }
+ if (what == OP_seek) {
+ seek = XATOU_SFX(arg, dd_suffixes);
+ continue;
+ }
+ if (what == skip) {
+ skip = XATOU_SFX(arg, dd_suffixes);
+ continue;
+ }
+ if (what == OP_if) {
+ infile = arg;
+ continue;
+ }
+ if (what == OP_of)
+ outfile = arg;
+ }
+//XXX:FIXME for huge ibs or obs, malloc'ing them isn't the brightest idea ever
+ ibuf = obuf = xmalloc(ibs);
+ if (ibs != obs) {
+ flags |= twobufs_flag;
+ obuf = xmalloc(obs);
+ }
+ if (infile != NULL)
+ ifd = xopen(infile, O_RDONLY);
+ else {
ifd = STDIN_FILENO;
- infile = "standard input";
+ infile = bb_msg_standard_input;
}
-
if (outfile != NULL) {
- oflag = O_WRONLY | O_CREAT;
+ int oflag = O_WRONLY | O_CREAT;
- if (!seek && trunc)
+ if (!seek && (flags & trunc_flag))
oflag |= O_TRUNC;
- if ((ofd = open(outfile, oflag, 0666)) < 0)
- perror_msg_and_die("%s", outfile);
+ ofd = xopen(outfile, oflag);
- if (seek && trunc) {
- if (ftruncate(ofd, seek * bs) < 0)
- perror_msg_and_die("%s", outfile);
- }
+ if (seek && (flags & 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))
+ goto die_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)
+ goto die_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)
+ goto die_outfile;
}
- while (in_full + in_part != count) {
- n = safe_read(ifd, buf, bs);
- if (n < 0)
- perror_msg_and_die("%s", infile);
+ while (G.in_full + G.in_part != count) {
+ if (flags & noerror) /* Pre-zero the buffer when for noerror */
+ memset(ibuf, '\0', ibs);
+ n = safe_read(ifd, ibuf, ibs);
if (n == 0)
break;
- if (n == bs)
- in_full++;
- else
- in_part++;
- if (sync_flag) {
- memset(buf + n, '\0', bs - n);
- n = bs;
+ if (n < 0) {
+ if (flags & noerror) {
+ n = ibs;
+ bb_perror_msg("%s", infile);
+ } else
+ goto die_infile;
}
- n = full_write(ofd, buf, n);
- if (n < 0)
- perror_msg_and_die("%s", outfile);
- if (n == bs)
- out_full++;
- else
- out_part++;
+ if ((size_t)n == ibs)
+ G.in_full++;
+ else {
+ G.in_part++;
+ if (flags & sync_flag) {
+ memset(ibuf + n, '\0', ibs - n);
+ n = ibs;
+ }
+ }
+ if (flags & 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 (write_and_stats(ofd, obuf, obs, obs, outfile))
+ goto out_status;
+ oc = 0;
+ }
+ }
+ } else
+ if (write_and_stats(ofd, ibuf, n, obs, outfile))
+ goto out_status;
+ }
+
+ if (ENABLE_FEATURE_DD_IBS_OBS && oc) {
+ w = full_write_or_warn(ofd, obuf, oc, outfile);
+ if (w < 0) goto out_status;
+ if (w > 0)
+ G.out_part++;
+ }
+ if (close(ifd) < 0) {
+die_infile:
+ bb_perror_msg_and_die("%s", infile);
}
- fprintf(statusfp, "%d+%d records in\n", in_full, in_part);
- fprintf(statusfp, "%d+%d records out\n", out_full, out_part);
+ if (close(ofd) < 0) {
+die_outfile:
+ bb_perror_msg_and_die("%s", outfile);
+ }
+out_status:
+ dd_output_status(0);
return EXIT_SUCCESS;
}