* 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 source tree.
*/
-#include <sys/types.h>
-#include <stdlib.h>
-#include <stdio.h>
-#include <unistd.h>
-#include <string.h>
-#include <fcntl.h>
-#include "busybox.h"
+//usage:#define dd_trivial_usage
+//usage: "[if=FILE] [of=FILE] " IF_FEATURE_DD_IBS_OBS("[ibs=N] [obs=N] ") "[bs=N] [count=N] [skip=N]\n"
+//usage: " [seek=N]" IF_FEATURE_DD_IBS_OBS(" [conv=notrunc|noerror|sync|fsync]")
+//usage:#define dd_full_usage "\n\n"
+//usage: "Copy a file with converting and formatting\n"
+//usage: "\n if=FILE Read from FILE instead of stdin"
+//usage: "\n of=FILE Write to FILE instead of stdout"
+//usage: "\n bs=N Read and write N bytes at a time"
+//usage: IF_FEATURE_DD_IBS_OBS(
+//usage: "\n ibs=N Read N bytes at a time"
+//usage: )
+//usage: IF_FEATURE_DD_IBS_OBS(
+//usage: "\n obs=N Write N bytes at a time"
+//usage: )
+//usage: "\n count=N Copy only N input blocks"
+//usage: "\n skip=N Skip N input blocks"
+//usage: "\n seek=N Skip N output blocks"
+//usage: IF_FEATURE_DD_IBS_OBS(
+//usage: "\n conv=notrunc Don't truncate output file"
+//usage: "\n conv=noerror Continue after read errors"
+//usage: "\n conv=sync Pad blocks with zeros"
+//usage: "\n conv=fsync Physically write data out before finishing"
+//usage: "\n conv=swab Swap every pair of bytes"
+//usage: )
+//usage: "\n"
+//usage: "\nN may be suffixed by c (1), w (2), b (512), kD (1000), k (1024), MD, M, GD, G"
+//usage:
+//usage:#define dd_example_usage
+//usage: "$ dd if=/dev/zero of=/dev/ram1 bs=1M count=4\n"
+//usage: "4+0 records in\n"
+//usage: "4+0 records out\n"
+
+#include "libbb.h"
+
+/* This is a NOEXEC applet. Be very careful! */
+enum {
+ ifd = STDIN_FILENO,
+ ofd = STDOUT_FILENO,
+};
+
static const struct suffix_mult dd_suffixes[] = {
{ "c", 1 },
{ "w", 2 },
{ "b", 512 },
{ "kD", 1000 },
{ "k", 1024 },
+ { "K", 1024 }, /* compat with coreutils dd */
{ "MD", 1000000 },
{ "M", 1048576 },
{ "GD", 1000000000 },
{ "G", 1073741824 },
- { NULL, 0 }
+ { "", 0 }
};
-int dd_main(int argc, char **argv)
+struct globals {
+ off_t out_full, out_part, in_full, in_part;
+#if ENABLE_FEATURE_DD_THIRD_STATUS_LINE
+ unsigned long long total_bytes;
+ unsigned long long begin_time_us;
+#endif
+} FIX_ALIASING;
+#define G (*(struct globals*)&bb_common_bufsiz1)
+#define INIT_G() do { \
+ /* we have to zero it out because of NOEXEC */ \
+ memset(&G, 0, sizeof(G)); \
+} while (0)
+
+
+static void dd_output_status(int UNUSED_PARAM cur_signal)
+{
+#if ENABLE_FEATURE_DD_THIRD_STATUS_LINE
+ double seconds;
+ unsigned long long bytes_sec;
+ unsigned long long now_us = monotonic_us(); /* before fprintf */
+#endif
+
+ /* Deliberately using %u, not %d */
+ fprintf(stderr, "%"OFF_FMT"u+%"OFF_FMT"u records in\n"
+ "%"OFF_FMT"u+%"OFF_FMT"u records out\n",
+ G.in_full, G.in_part,
+ G.out_full, G.out_part);
+
+#if ENABLE_FEATURE_DD_THIRD_STATUS_LINE
+ fprintf(stderr, "%llu bytes (%sB) copied, ",
+ G.total_bytes,
+ /* show fractional digit, use suffixes */
+ make_human_readable_str(G.total_bytes, 1, 0)
+ );
+ /* Corner cases:
+ * ./busybox dd </dev/null >/dev/null
+ * ./busybox dd bs=1M count=2000 </dev/zero >/dev/null
+ * (echo DONE) | ./busybox dd >/dev/null
+ * (sleep 1; echo DONE) | ./busybox dd >/dev/null
+ */
+ seconds = (now_us - G.begin_time_us) / 1000000.0;
+ bytes_sec = G.total_bytes / seconds;
+ fprintf(stderr, "%f seconds, %sB/s\n",
+ seconds,
+ /* show fractional digit, use suffixes */
+ make_human_readable_str(bytes_sec, 1, 0)
+ );
+#endif
+}
+
+static ssize_t full_write_or_warn(const void *buf, size_t len,
+ const char *const filename)
+{
+ ssize_t n = full_write(ofd, buf, len);
+ if (n < 0)
+ bb_perror_msg("writing '%s'", filename);
+ return n;
+}
+
+static bool write_and_stats(const void *buf, size_t len, size_t obs,
+ const char *filename)
{
- 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;
+ ssize_t n = full_write_or_warn(buf, len, filename);
+ if (n < 0)
+ return 1;
+ if ((size_t)n == obs)
+ G.out_full++;
+ else if (n) /* > 0 */
+ G.out_part++;
+#if ENABLE_FEATURE_DD_THIRD_STATUS_LINE
+ G.total_bytes += n;
+#endif
+ return 0;
+}
+
+#if ENABLE_LFS
+# define XATOU_SFX xatoull_sfx
+#else
+# define XATOU_SFX xatoul_sfx
+#endif
+
+int dd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int dd_main(int argc UNUSED_PARAM, char **argv)
+{
+ enum {
+ /* Must be in the same order as OP_conv_XXX! */
+ /* (see "flags |= (1 << what)" below) */
+ FLAG_NOTRUNC = (1 << 0) * ENABLE_FEATURE_DD_IBS_OBS,
+ FLAG_SYNC = (1 << 1) * ENABLE_FEATURE_DD_IBS_OBS,
+ FLAG_NOERROR = (1 << 2) * ENABLE_FEATURE_DD_IBS_OBS,
+ FLAG_FSYNC = (1 << 3) * ENABLE_FEATURE_DD_IBS_OBS,
+ FLAG_SWAB = (1 << 4) * ENABLE_FEATURE_DD_IBS_OBS,
+ /* end of conv flags */
+ FLAG_TWOBUFS = (1 << 5) * ENABLE_FEATURE_DD_IBS_OBS,
+ FLAG_COUNT = 1 << 6,
+ };
+ static const char keywords[] ALIGN1 =
+ "bs\0""count\0""seek\0""skip\0""if\0""of\0"
+#if ENABLE_FEATURE_DD_IBS_OBS
+ "ibs\0""obs\0""conv\0"
+#endif
+ ;
+#if ENABLE_FEATURE_DD_IBS_OBS
+ static const char conv_words[] ALIGN1 =
+ "notrunc\0""sync\0""noerror\0""fsync\0""swab\0";
+#endif
+ enum {
+ OP_bs = 0,
+ OP_count,
+ OP_seek,
+ OP_skip,
+ OP_if,
+ OP_of,
+#if ENABLE_FEATURE_DD_IBS_OBS
+ OP_ibs,
+ OP_obs,
+ OP_conv,
+ /* Must be in the same order as FLAG_XXX! */
+ OP_conv_notrunc = 0,
+ OP_conv_sync,
+ OP_conv_noerror,
+ OP_conv_fsync,
+ OP_conv_swab,
+ /* Unimplemented conv=XXX: */
+ //nocreat do not create the output file
+ //excl fail if the output file already exists
+ //fdatasync physically write output file data before finishing
+ //lcase change upper case to lower case
+ //ucase change lower case to upper case
+ //block pad newline-terminated records with spaces to cbs-size
+ //unblock replace trailing spaces in cbs-size records with newline
+ //ascii from EBCDIC to ASCII
+ //ebcdic from ASCII to EBCDIC
+ //ibm from ASCII to alternate EBCDIC
+ /* Partially implemented: */
+ //swab swap every pair of input bytes: will abort on non-even reads
+#endif
+ };
+ smallint exitcode = EXIT_FAILURE;
+ int i;
+ size_t ibs = 512;
+ char *ibuf;
+#if ENABLE_FEATURE_DD_IBS_OBS
+ size_t obs = 512;
+ char *obuf;
+#else
+# define obs ibs
+# define obuf ibuf
+#endif
+ /* These are all zeroed at once! */
+ struct {
+ int flags;
+ size_t oc;
+ ssize_t prev_read_size; /* for detecting swab failure */
+ off_t count;
+ off_t seek, skip;
+ const char *infile, *outfile;
+ } Z;
+#define flags (Z.flags )
+#define oc (Z.oc )
+#define prev_read_size (Z.prev_read_size)
+#define count (Z.count )
+#define seek (Z.seek )
+#define skip (Z.skip )
+#define infile (Z.infile )
+#define outfile (Z.outfile)
+
+ memset(&Z, 0, sizeof(Z));
+ INIT_G();
+ //fflush_all(); - is this needed because of NOEXEC?
+
+ for (i = 1; argv[i]; i++) {
+ int what;
+ char *val;
+ char *arg = argv[i];
+
+#if ENABLE_DESKTOP
+ /* "dd --". NB: coreutils 6.9 will complain if they see
+ * more than one of them. We wouldn't. */
+ if (arg[0] == '-' && arg[1] == '-' && arg[2] == '\0')
+ continue;
+#endif
+ val = strchr(arg, '=');
+ if (val == NULL)
+ bb_show_usage();
+ *val = '\0';
+ what = index_in_strings(keywords, arg);
+ if (what < 0)
+ bb_show_usage();
+ /* *val = '='; - to preserve ps listing? */
+ val++;
+#if ENABLE_FEATURE_DD_IBS_OBS
+ if (what == OP_ibs) {
+ /* Must fit into positive ssize_t */
+ ibs = xatoul_range_sfx(val, 1, ((size_t)-1L)/2, dd_suffixes);
+ /*continue;*/
+ }
+ if (what == OP_obs) {
+ obs = xatoul_range_sfx(val, 1, ((size_t)-1L)/2, dd_suffixes);
+ /*continue;*/
+ }
+ if (what == OP_conv) {
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')
+ int n;
+ /* find ',', replace them with NUL so we can use val for
+ * index_in_strings() without copying.
+ * We rely on val being non-null, else strchr would fault.
+ */
+ arg = strchr(val, ',');
+ if (arg)
+ *arg = '\0';
+ n = index_in_strings(conv_words, val);
+ if (n < 0)
+ bb_error_msg_and_die(bb_msg_invalid_arg, val, "conv");
+ flags |= (1 << n);
+ if (!arg) /* no ',' left, so this was the last specifier */
break;
- if (buf[0] == ',')
- buf++;
+ /* *arg = ','; - to preserve ps listing? */
+ val = arg + 1; /* skip this keyword and ',' */
}
- } else
- show_usage();
+ /*continue;*/
+ }
+#endif
+ if (what == OP_bs) {
+ ibs = xatoul_range_sfx(val, 1, ((size_t)-1L)/2, dd_suffixes);
+ obs = ibs;
+ /*continue;*/
+ }
+ /* These can be large: */
+ if (what == OP_count) {
+ flags |= FLAG_COUNT;
+ count = XATOU_SFX(val, dd_suffixes);
+ /*continue;*/
+ }
+ if (what == OP_seek) {
+ seek = XATOU_SFX(val, dd_suffixes);
+ /*continue;*/
+ }
+ if (what == OP_skip) {
+ skip = XATOU_SFX(val, dd_suffixes);
+ /*continue;*/
+ }
+ if (what == OP_if) {
+ infile = val;
+ /*continue;*/
+ }
+ if (what == OP_of) {
+ outfile = val;
+ /*continue;*/
+ }
+ } /* end of "for (argv[i])" */
+
+//XXX:FIXME for huge ibs or obs, malloc'ing them isn't the brightest idea ever
+ ibuf = xmalloc(ibs);
+ obuf = ibuf;
+#if ENABLE_FEATURE_DD_IBS_OBS
+ if (ibs != obs) {
+ flags |= FLAG_TWOBUFS;
+ obuf = xmalloc(obs);
}
+#endif
- buf = xmalloc(bs);
+#if ENABLE_FEATURE_DD_SIGNAL_HANDLING
+ signal_SA_RESTART_empty_mask(SIGUSR1, dd_output_status);
+#endif
+#if ENABLE_FEATURE_DD_THIRD_STATUS_LINE
+ G.begin_time_us = monotonic_us();
+#endif
- if (infile != NULL) {
- if ((ifd = open(infile, O_RDONLY)) < 0)
- perror_msg_and_die("%s", infile);
+ if (infile) {
+ xmove_fd(xopen(infile, O_RDONLY), ifd);
} else {
- ifd = STDIN_FILENO;
- infile = "standard input";
+ infile = bb_msg_standard_input;
}
+ if (outfile) {
+ int oflag = O_WRONLY | O_CREAT;
- if (outfile != NULL) {
- oflag = O_WRONLY | O_CREAT;
-
- if (!seek && trunc)
+ if (!seek && !(flags & FLAG_NOTRUNC))
oflag |= O_TRUNC;
- if ((ofd = open(outfile, oflag, 0666)) < 0)
- perror_msg_and_die("%s", outfile);
+ xmove_fd(xopen(outfile, oflag), ofd);
- if (seek && trunc) {
- if (ftruncate(ofd, seek * bs) < 0)
- perror_msg_and_die("%s", outfile);
- }
+ if (seek && !(flags & FLAG_NOTRUNC)) {
+ 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) {
+ do {
+ ssize_t n = safe_read(ifd, ibuf, ibs);
+ if (n < 0)
+ goto die_infile;
+ if (n == 0)
+ break;
+ } while (--skip != 0);
+ }
}
-
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 (!(flags & FLAG_COUNT) || (G.in_full + G.in_part != count)) {
+ ssize_t n;
+
+ 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;
- }
- n = full_write(ofd, buf, n);
- if (n < 0)
- perror_msg_and_die("%s", outfile);
- if (n == bs)
- out_full++;
- else
- out_part++;
+ if (n < 0) {
+ /* "Bad block" */
+ if (!(flags & FLAG_NOERROR))
+ goto die_infile;
+ bb_simple_perror_msg(infile);
+ /* GNU dd with conv=noerror skips over bad blocks */
+ xlseek(ifd, ibs, SEEK_CUR);
+ /* conv=noerror,sync writes NULs,
+ * conv=noerror just ignores input bad blocks */
+ n = 0;
+ }
+ if (flags & FLAG_SWAB) {
+ uint16_t *p16;
+ ssize_t n2;
+
+ /* Our code allows only last read to be odd-sized */
+ if (prev_read_size & 1)
+ bb_error_msg_and_die("can't swab %lu byte buffer",
+ (unsigned long)prev_read_size);
+ prev_read_size = n;
+
+ /* If n is odd, last byte is not swapped:
+ * echo -n "qwe" | dd conv=swab
+ * prints "wqe".
+ */
+ p16 = (void*) ibuf;
+ n2 = (n >> 1);
+ while (--n2 >= 0) {
+ *p16 = bswap_16(*p16);
+ p16++;
+ }
+ }
+ if ((size_t)n == ibs)
+ G.in_full++;
+ else {
+ G.in_part++;
+ if (flags & FLAG_SYNC) {
+ memset(ibuf + n, 0, ibs - n);
+ n = ibs;
+ }
+ }
+ if (flags & FLAG_TWOBUFS) {
+ char *tmp = ibuf;
+ while (n) {
+ size_t d = obs - oc;
+
+ if (d > (size_t)n)
+ d = n;
+ memcpy(obuf + oc, tmp, d);
+ n -= d;
+ tmp += d;
+ oc += d;
+ if (oc == obs) {
+ if (write_and_stats(obuf, obs, obs, outfile))
+ goto out_status;
+ oc = 0;
+ }
+ }
+ } else {
+ if (write_and_stats(ibuf, n, obs, outfile))
+ goto out_status;
+ }
+
+ if (flags & FLAG_FSYNC) {
+ if (fsync(ofd) < 0)
+ goto die_outfile;
+ }
+ }
+
+ if (ENABLE_FEATURE_DD_IBS_OBS && oc) {
+ if (write_and_stats(obuf, oc, obs, outfile))
+ goto out_status;
+ }
+ if (close(ifd) < 0) {
+ die_infile:
+ bb_simple_perror_msg_and_die(infile);
}
- fprintf(statusfp, "%ld+%ld records in\n", (long)in_full, (long)in_part);
- fprintf(statusfp, "%ld+%ld records out\n", (long)out_full, (long)out_part);
+ if (close(ofd) < 0) {
+ die_outfile:
+ bb_simple_perror_msg_and_die(outfile);
+ }
+
+ exitcode = EXIT_SUCCESS;
+ out_status:
+ dd_output_status(0);
+
+ if (ENABLE_FEATURE_CLEAN_UP) {
+ free(obuf);
+ if (flags & FLAG_TWOBUFS)
+ free(ibuf);
+ }
- return EXIT_SUCCESS;
+ return exitcode;
}
projects / platform / upstream / busybox.git / blobdiff