X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;ds=sidebyside;f=coreutils%2Fdd.c;h=43545c01074f028f2b6a11c57dc506ff215a9d14;hb=86d5bf4246a7ba68d220bc6c7a7a3be62119dc12;hp=797aabdd931ad1ecca395ad743a0987a34db8acd;hpb=d1801a44301ae10910763de860614b1aed9922d7;p=oweals%2Fbusybox.git

diff --git a/coreutils/dd.c b/coreutils/dd.c
index 797aabdd9..43545c010 100644
--- a/coreutils/dd.c
+++ b/coreutils/dd.c
@@ -2,243 +2,460 @@
 /*
  * Mini dd implementation for busybox
  *
- *
  * Copyright (C) 2000,2001  Matt Kraai
  *
- * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
  */
+//config:config DD
+//config:	bool "dd (7.1 kb)"
+//config:	default y
+//config:	help
+//config:	dd copies a file (from standard input to standard output,
+//config:	by default) using specific input and output blocksizes,
+//config:	while optionally performing conversions on it.
+//config:
+//config:config FEATURE_DD_SIGNAL_HANDLING
+//config:	bool "Enable signal handling for status reporting"
+//config:	default y
+//config:	depends on DD
+//config:	help
+//config:	Sending a SIGUSR1 signal to a running `dd' process makes it
+//config:	print to standard error the number of records read and written
+//config:	so far, then to resume copying.
+//config:
+//config:	$ dd if=/dev/zero of=/dev/null &
+//config:	$ pid=$!; kill -USR1 $pid; sleep 1; kill $pid
+//config:	10899206+0 records in
+//config:	10899206+0 records out
+//config:
+//config:config FEATURE_DD_THIRD_STATUS_LINE
+//config:	bool "Enable the third status line upon signal"
+//config:	default y
+//config:	depends on DD && FEATURE_DD_SIGNAL_HANDLING
+//config:	help
+//config:	Displays a coreutils-like third status line with transferred bytes,
+//config:	elapsed time and speed.
+//config:
+//config:config FEATURE_DD_IBS_OBS
+//config:	bool "Enable ibs, obs and conv options"
+//config:	default y
+//config:	depends on DD
+//config:	help
+//config:	Enable support for writing a certain number of bytes in and out,
+//config:	at a time, and performing conversions on the data stream.
+//config:
+//config:config FEATURE_DD_STATUS
+//config:	bool "Enable status display options"
+//config:	default y
+//config:	depends on DD
+//config:	help
+//config:	Enable support for status=noxfer/none option.
+
+//applet:IF_DD(APPLET_NOEXEC(dd, dd, BB_DIR_BIN, BB_SUID_DROP, dd))
+
+//kbuild:lib-$(CONFIG_DD) += dd.o
 
-#include <signal.h>  /* For FEATURE_DD_SIGNAL_HANDLING */
-#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] [iflag=skip_bytes]")
+//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:     "\n	iflag=skip_bytes	skip=N is in bytes"
+//usage:	)
+//usage:	IF_FEATURE_DD_STATUS(
+//usage:     "\n	status=noxfer	Suppress rate output"
+//usage:     "\n	status=none	Suppress all output"
+//usage:	)
+//usage:     "\n"
+//usage:     "\nN may be suffixed by c (1), w (2), b (512), kB (1000), k (1024), MB, M, GB, 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"
+#include "common_bufsiz.h"
 
 /* This is a NOEXEC applet. Be very careful! */
 
 
-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 }
+enum {
+	ifd = STDIN_FILENO,
+	ofd = STDOUT_FILENO,
 };
 
 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
+	int flags;
+} FIX_ALIASING;
+#define G (*(struct globals*)bb_common_bufsiz1)
+#define INIT_G() do { \
+	setup_common_bufsiz(); \
+	/* we have to zero it out because of NOEXEC */ \
+	memset(&G, 0, sizeof(G)); \
+} while (0)
+
+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 */
+	/* start of input flags */
+	FLAG_IFLAG_SHIFT = 5,
+	FLAG_SKIP_BYTES = (1 << 5) * ENABLE_FEATURE_DD_IBS_OBS,
+	/* end of input flags */
+	FLAG_TWOBUFS = (1 << 6) * ENABLE_FEATURE_DD_IBS_OBS,
+	FLAG_COUNT   = 1 << 7,
+	FLAG_STATUS_NONE = 1 << 8,
+	FLAG_STATUS_NOXFER = 1 << 9,
 };
-#define G (*(struct globals*)&bb_common_bufsiz1)
 
-static void dd_output_status(int ATTRIBUTE_UNUSED cur_signal)
+static void dd_output_status(int UNUSED_PARAM cur_signal)
 {
-	fprintf(stderr, "%"OFF_FMT"d+%"OFF_FMT"d records in\n"
-			"%"OFF_FMT"d+%"OFF_FMT"d records out\n",
+#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
+# if ENABLE_FEATURE_DD_STATUS
+	if (G.flags & FLAG_STATUS_NOXFER) /* status=noxfer active? */
+		return;
+	//TODO: should status=none make dd stop reacting to USR1 entirely?
+	//So far we react to it (we print the stats),
+	//status=none only suppresses final, non-USR1 generated status message.
+# endif
+	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(int fd, const void *buf, size_t len,
-	const char * const filename)
+static ssize_t full_write_or_warn(const void *buf, size_t len,
+	const char *const filename)
 {
-	ssize_t n = full_write(fd, buf, len);
+	ssize_t n = full_write(ofd, 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)
+static bool write_and_stats(const void *buf, size_t len, size_t obs,
+	const char *filename)
 {
-	ssize_t n = full_write_or_warn(fd, buf, len, filename);
+	ssize_t n = full_write_or_warn(buf, len, filename);
 	if (n < 0)
 		return 1;
-	if (n == obs)
+	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
+# define XATOU_SFX xatoull_sfx
 #else
-#define XATOU_SFX xatoul_sfx
+# define XATOU_SFX xatoul_sfx
 #endif
 
-int dd_main(int argc, char **argv);
-int dd_main(int argc, char **argv)
+#if ENABLE_FEATURE_DD_IBS_OBS
+static int parse_comma_flags(char *val, const char *words, const char *error_in)
 {
-	enum {
-		SYNC_FLAG    = 1 << 0,
-		NOERROR      = 1 << 1,
-		TRUNC_FLAG   = 1 << 2,
-		TWOBUFS_FLAG = 1 << 3,
-	};
-	static const char * const keywords[] = {
-		"bs=", "count=", "seek=", "skip=", "if=", "of=",
+	int flags = 0;
+	while (1) {
+		int n;
+		char *arg;
+		/* 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(words, val);
+		if (n < 0)
+			bb_error_msg_and_die(bb_msg_invalid_arg_to, val, error_in);
+		flags |= (1 << n);
+		if (!arg) /* no ',' left, so this was the last specifier */
+			break;
+		*arg = ','; /* to preserve ps listing */
+		val = arg + 1; /* skip this keyword and ',' */
+	}
+	return flags;
+}
+#endif
+
+int dd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int dd_main(int argc UNUSED_PARAM, char **argv)
+{
+	static const char keywords[] ALIGN1 =
+		"bs\0""count\0""seek\0""skip\0""if\0""of\0"IF_FEATURE_DD_STATUS("status\0")
 #if ENABLE_FEATURE_DD_IBS_OBS
-		"ibs=", "obs=", "conv=", "notrunc", "sync", "noerror",
+		"ibs\0""obs\0""conv\0""iflag\0"
+#endif
+		;
+#if ENABLE_FEATURE_DD_IBS_OBS
+	static const char conv_words[] ALIGN1 =
+		"notrunc\0""sync\0""noerror\0""fsync\0""swab\0";
+	static const char iflag_words[] ALIGN1 =
+		"skip_bytes\0";
+#endif
+#if ENABLE_FEATURE_DD_STATUS
+	static const char status_words[] ALIGN1 =
+		"none\0""noxfer\0";
 #endif
-		NULL
-	};
 	enum {
-		OP_bs = 1,
+		OP_bs = 0,
 		OP_count,
 		OP_seek,
 		OP_skip,
 		OP_if,
 		OP_of,
+		IF_FEATURE_DD_STATUS(OP_status,)
 #if ENABLE_FEATURE_DD_IBS_OBS
 		OP_ibs,
 		OP_obs,
 		OP_conv,
-		OP_conv_notrunc,
+		OP_iflag,
+		/* Must be in the same order as FLAG_XXX! */
+		OP_conv_notrunc = 0,
 		OP_conv_sync,
-		OP_conv_NOERROR,
+		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
+		OP_iflag_skip_bytes,
 #endif
 	};
-	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);
-	}
+	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 {
+		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 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)
 
-	for (n = 1; n < argc; n++) {
-		smalluint key_len;
-		smalluint what;
-		char *key;
-		char *arg = argv[n];
+	memset(&Z, 0, sizeof(Z));
+	INIT_G();
+	//fflush_all(); - is this needed because of NOEXEC?
 
-//XXX:FIXME: we reject plain "dd --" This would cost ~20 bytes, so..
-//if (*arg == '-' && *++arg == '-' && !*++arg) continue;
-		key = strstr(arg, "=");
-		if (key == NULL)
+	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();
-		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)
+		*val = '\0';
+		what = index_in_strings(keywords, arg);
+		if (what < 0)
 			bb_show_usage();
-		arg += key_len;
-		/* Must fit into positive ssize_t */
+		/* *val = '='; - to preserve ps listing? */
+		val++;
 #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 strchr would fault.
-					 */
-					key = strchr(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 + 1; /* skip this keyword and ',' */
-				}
-				continue;
-			}
+		if (what == OP_ibs) {
+			/* Must fit into positive ssize_t */
+			ibs = xatoul_range_sfx(val, 1, ((size_t)-1L)/2, cwbkMG_suffixes);
+			/*continue;*/
+		}
+		if (what == OP_obs) {
+			obs = xatoul_range_sfx(val, 1, ((size_t)-1L)/2, cwbkMG_suffixes);
+			/*continue;*/
+		}
+		if (what == OP_conv) {
+			G.flags |= parse_comma_flags(val, conv_words, "conv");
+			/*continue;*/
+		}
+		if (what == OP_iflag) {
+			G.flags |= parse_comma_flags(val, iflag_words, "iflag") << FLAG_IFLAG_SHIFT;
+			/*continue;*/
+		}
 #endif
 		if (what == OP_bs) {
-			ibs = obs = xatoul_range_sfx(arg, 1, ((size_t)-1L)/2, dd_suffixes);
-			continue;
+			ibs = xatoul_range_sfx(val, 1, ((size_t)-1L)/2, cwbkMG_suffixes);
+			obs = ibs;
+			/*continue;*/
 		}
 		/* These can be large: */
 		if (what == OP_count) {
-			count = XATOU_SFX(arg, dd_suffixes);
-			continue;
+			G.flags |= FLAG_COUNT;
+			count = XATOU_SFX(val, cwbkMG_suffixes);
+			/*continue;*/
 		}
 		if (what == OP_seek) {
-			seek = XATOU_SFX(arg, dd_suffixes);
-			continue;
+			seek = XATOU_SFX(val, cwbkMG_suffixes);
+			/*continue;*/
 		}
 		if (what == OP_skip) {
-			skip = XATOU_SFX(arg, dd_suffixes);
-			continue;
+			skip = XATOU_SFX(val, cwbkMG_suffixes);
+			/*continue;*/
 		}
 		if (what == OP_if) {
-			infile = arg;
-			continue;
+			infile = val;
+			/*continue;*/
 		}
-		if (what == OP_of)
-			outfile = arg;
-	}
+		if (what == OP_of) {
+			outfile = val;
+			/*continue;*/
+		}
+#if ENABLE_FEATURE_DD_STATUS
+		if (what == OP_status) {
+			int n;
+			n = index_in_strings(status_words, val);
+			if (n < 0)
+				bb_error_msg_and_die(bb_msg_invalid_arg_to, val, "status");
+			G.flags |= FLAG_STATUS_NONE << n;
+			/*continue;*/
+		}
+#endif
+	} /* end of "for (argv[i])" */
+
 //XXX:FIXME for huge ibs or obs, malloc'ing them isn't the brightest idea ever
-	ibuf = obuf = xmalloc(ibs);
+	ibuf = xmalloc(ibs);
+	obuf = ibuf;
+#if ENABLE_FEATURE_DD_IBS_OBS
 	if (ibs != obs) {
-		flags |= TWOBUFS_FLAG;
+		G.flags |= FLAG_TWOBUFS;
 		obuf = xmalloc(obs);
 	}
-	if (infile != NULL)
-		ifd = xopen(infile, O_RDONLY);
-	else {
-		ifd = STDIN_FILENO;
+#endif
+
+#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) {
+		xmove_fd(xopen(infile, O_RDONLY), ifd);
+	} else {
 		infile = bb_msg_standard_input;
 	}
-	if (outfile != NULL) {
+	if (outfile) {
 		int oflag = O_WRONLY | O_CREAT;
 
-		if (!seek && (flags & TRUNC_FLAG))
+		if (!seek && !(G.flags & FLAG_NOTRUNC))
 			oflag |= O_TRUNC;
 
-		ofd = xopen(outfile, oflag);
+		xmove_fd(xopen(outfile, oflag), ofd);
 
-		if (seek && (flags & TRUNC_FLAG)) {
+		if (seek && !(G.flags & FLAG_NOTRUNC)) {
 			if (ftruncate(ofd, seek * obs) < 0) {
 				struct stat st;
 
-				if (fstat(ofd, &st) < 0 || S_ISREG(st.st_mode) ||
-						S_ISDIR(st.st_mode))
+				if (fstat(ofd, &st) < 0
+				 || S_ISREG(st.st_mode)
+				 || S_ISDIR(st.st_mode)
+				) {
 					goto die_outfile;
+				}
 			}
 		}
 	} else {
-		ofd = STDOUT_FILENO;
 		outfile = bb_msg_standard_output;
 	}
 	if (skip) {
-		if (lseek(ifd, skip * ibs, SEEK_CUR) < 0) {
-			while (skip-- > 0) {
-				n = safe_read(ifd, ibuf, ibs);
+		size_t blocksz = (G.flags & FLAG_SKIP_BYTES) ? 1 : ibs;
+		if (lseek(ifd, skip * blocksz, SEEK_CUR) < 0) {
+			do {
+				ssize_t n = safe_read(ifd, ibuf, blocksz);
 				if (n < 0)
 					goto die_infile;
 				if (n == 0)
 					break;
-			}
+			} while (--skip != 0);
 		}
 	}
 	if (seek) {
@@ -246,66 +463,105 @@ int dd_main(int argc, char **argv)
 			goto die_outfile;
 	}
 
-	while (G.in_full + G.in_part != count) {
-		if (flags & NOERROR) /* Pre-zero the buffer when for NOERROR */
-			memset(ibuf, '\0', ibs);
+	while (!(G.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 < 0) {
-			if (flags & NOERROR) {
-				n = ibs;
-				bb_perror_msg("%s", infile);
-			} else
+			/* "Bad block" */
+			if (!(G.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 (G.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 & SYNC_FLAG) {
-				memset(ibuf + n, '\0', ibs - n);
+			if (G.flags & FLAG_SYNC) {
+				memset(ibuf + n, 0, ibs - n);
 				n = ibs;
 			}
 		}
-		if (flags & TWOBUFS_FLAG) {
+		if (G.flags & FLAG_TWOBUFS) {
 			char *tmp = ibuf;
 			while (n) {
 				size_t d = obs - oc;
 
-				if (d > n)
+				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(ofd, obuf, obs, obs, outfile))
+					if (write_and_stats(obuf, obs, obs, outfile))
 						goto out_status;
 					oc = 0;
 				}
 			}
-		} else if (write_and_stats(ofd, ibuf, n, obs, outfile))
-			goto out_status;
+		} else {
+			if (write_and_stats(ibuf, n, obs, outfile))
+				goto out_status;
+		}
+	}
+
+	if (G.flags & FLAG_FSYNC) {
+		if (fsync(ofd) < 0)
+			goto die_outfile;
 	}
 
 	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 (write_and_stats(obuf, oc, obs, outfile))
+			goto out_status;
 	}
 	if (close(ifd) < 0) {
-die_infile:
-		bb_perror_msg_and_die("%s", infile);
+ die_infile:
+		bb_simple_perror_msg_and_die(infile);
 	}
 
 	if (close(ofd) < 0) {
-die_outfile:
-		bb_perror_msg_and_die("%s", outfile);
+ die_outfile:
+		bb_simple_perror_msg_and_die(outfile);
+	}
+
+	exitcode = EXIT_SUCCESS;
+ out_status:
+	if (!ENABLE_FEATURE_DD_STATUS || !(G.flags & FLAG_STATUS_NONE))
+		dd_output_status(0);
+
+	if (ENABLE_FEATURE_CLEAN_UP) {
+		free(obuf);
+		if (G.flags & FLAG_TWOBUFS)
+			free(ibuf);
 	}
-out_status:
-	dd_output_status(0);
 
-	return EXIT_SUCCESS;
+	return exitcode;
 }