611 lines
		
	
	
		
			16 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			611 lines
		
	
	
		
			16 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* vi: set sw=4 ts=4: */
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| /*
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|  * Mini dd implementation for busybox
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|  *
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|  * Copyright (C) 2000,2001  Matt Kraai
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|  *
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|  * Licensed under GPLv2 or later, see file LICENSE in this source tree.
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|  */
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| //config:config DD
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| //config:	bool "dd (7.5 kb)"
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| //config:	default y
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| //config:	help
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| //config:	dd copies a file (from standard input to standard output,
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| //config:	by default) using specific input and output blocksizes,
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| //config:	while optionally performing conversions on it.
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| //config:
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| //config:config FEATURE_DD_SIGNAL_HANDLING
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| //config:	bool "Enable signal handling for status reporting"
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| //config:	default y
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| //config:	depends on DD
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| //config:	help
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| //config:	Sending a SIGUSR1 signal to a running 'dd' process makes it
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| //config:	print to standard error the number of records read and written
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| //config:	so far, then to resume copying.
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| //config:
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| //config:	$ dd if=/dev/zero of=/dev/null &
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| //config:	$ pid=$!; kill -USR1 $pid; sleep 1; kill $pid
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| //config:	10899206+0 records in
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| //config:	10899206+0 records out
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| //config:
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| //config:config FEATURE_DD_THIRD_STATUS_LINE
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| //config:	bool "Enable the third status line upon signal"
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| //config:	default y
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| //config:	depends on DD && FEATURE_DD_SIGNAL_HANDLING
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| //config:	help
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| //config:	Displays a coreutils-like third status line with transferred bytes,
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| //config:	elapsed time and speed.
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| //config:
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| //config:config FEATURE_DD_IBS_OBS
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| //config:	bool "Enable ibs, obs, iflag, oflag and conv options"
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| //config:	default y
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| //config:	depends on DD
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| //config:	help
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| //config:	Enable support for writing a certain number of bytes in and out,
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| //config:	at a time, and performing conversions on the data stream.
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| //config:
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| //config:config FEATURE_DD_STATUS
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| //config:	bool "Enable status display options"
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| //config:	default y
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| //config:	depends on DD
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| //config:	help
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| //config:	Enable support for status=noxfer/none option.
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| 
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| //applet:IF_DD(APPLET_NOEXEC(dd, dd, BB_DIR_BIN, BB_SUID_DROP, dd))
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| 
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| //kbuild:lib-$(CONFIG_DD) += dd.o
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| 
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| //usage:#define dd_trivial_usage
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| //usage:       "[if=FILE] [of=FILE] [" IF_FEATURE_DD_IBS_OBS("ibs=N obs=N/") "bs=N] [count=N] [skip=N] [seek=N]\n"
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| //usage:	IF_FEATURE_DD_IBS_OBS(
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| //usage:       "	[conv=notrunc|noerror|sync|fsync]\n"
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| //usage:       "	[iflag=skip_bytes|fullblock] [oflag=seek_bytes|append]"
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| //usage:	)
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| //usage:#define dd_full_usage "\n\n"
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| //usage:       "Copy a file with converting and formatting\n"
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| //usage:     "\n	if=FILE		Read from FILE instead of stdin"
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| //usage:     "\n	of=FILE		Write to FILE instead of stdout"
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| //usage:     "\n	bs=N		Read and write N bytes at a time"
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| //usage:	IF_FEATURE_DD_IBS_OBS(
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| //usage:     "\n	ibs=N		Read N bytes at a time"
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| //usage:	)
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| //usage:	IF_FEATURE_DD_IBS_OBS(
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| //usage:     "\n	obs=N		Write N bytes at a time"
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| //usage:	)
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| //usage:     "\n	count=N		Copy only N input blocks"
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| //usage:     "\n	skip=N		Skip N input blocks"
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| //usage:     "\n	seek=N		Skip N output blocks"
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| //usage:	IF_FEATURE_DD_IBS_OBS(
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| //usage:     "\n	conv=notrunc	Don't truncate output file"
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| //usage:     "\n	conv=noerror	Continue after read errors"
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| //usage:     "\n	conv=sync	Pad blocks with zeros"
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| //usage:     "\n	conv=fsync	Physically write data out before finishing"
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| //usage:     "\n	conv=swab	Swap every pair of bytes"
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| //usage:     "\n	iflag=skip_bytes	skip=N is in bytes"
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| //usage:     "\n	iflag=fullblock	Read full blocks"
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| //usage:     "\n	oflag=seek_bytes	seek=N is in bytes"
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| //usage:     "\n	oflag=append	Open output file in append mode"
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| //usage:	)
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| //usage:	IF_FEATURE_DD_STATUS(
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| //usage:     "\n	status=noxfer	Suppress rate output"
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| //usage:     "\n	status=none	Suppress all output"
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| //usage:	)
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| //usage:     "\n"
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| //usage:     "\nN may be suffixed by c (1), w (2), b (512), kB (1000), k (1024), MB, M, GB, G"
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| //usage:
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| //usage:#define dd_example_usage
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| //usage:       "$ dd if=/dev/zero of=/dev/ram1 bs=1M count=4\n"
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| //usage:       "4+0 records in\n"
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| //usage:       "4+0 records out\n"
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| 
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| #include "libbb.h"
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| #include "common_bufsiz.h"
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| 
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| /* This is a NOEXEC applet. Be very careful! */
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| 
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| 
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| enum {
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| 	ifd = STDIN_FILENO,
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| 	ofd = STDOUT_FILENO,
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| };
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| 
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| struct globals {
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| 	off_t out_full, out_part, in_full, in_part;
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| #if ENABLE_FEATURE_DD_THIRD_STATUS_LINE
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| 	unsigned long long total_bytes;
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| 	unsigned long long begin_time_us;
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| #endif
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| 	int flags;
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| } FIX_ALIASING;
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| #define G (*(struct globals*)bb_common_bufsiz1)
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| #define INIT_G() do { \
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| 	setup_common_bufsiz(); \
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| 	/* we have to zero it out because of NOEXEC */ \
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| 	memset(&G, 0, sizeof(G)); \
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| } while (0)
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| 
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| enum {
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| 	/* Must be in the same order as OP_conv_XXX! */
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| 	/* (see "flags |= (1 << what)" below) */
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| 	FLAG_NOTRUNC = (1 << 0) * ENABLE_FEATURE_DD_IBS_OBS,
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| 	FLAG_SYNC    = (1 << 1) * ENABLE_FEATURE_DD_IBS_OBS,
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| 	FLAG_NOERROR = (1 << 2) * ENABLE_FEATURE_DD_IBS_OBS,
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| 	FLAG_FSYNC   = (1 << 3) * ENABLE_FEATURE_DD_IBS_OBS,
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| 	FLAG_SWAB    = (1 << 4) * ENABLE_FEATURE_DD_IBS_OBS,
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| 	/* end of conv flags */
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| 	/* start of input flags */
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| 	FLAG_IFLAG_SHIFT = 5,
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| 	FLAG_SKIP_BYTES = (1 << 5) * ENABLE_FEATURE_DD_IBS_OBS,
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| 	FLAG_FULLBLOCK = (1 << 6) * ENABLE_FEATURE_DD_IBS_OBS,
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| 	/* end of input flags */
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| 	/* start of output flags */
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| 	FLAG_OFLAG_SHIFT = 7,
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| 	FLAG_SEEK_BYTES = (1 << 7) * ENABLE_FEATURE_DD_IBS_OBS,
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| 	FLAG_APPEND = (1 << 8) * ENABLE_FEATURE_DD_IBS_OBS,
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| 	/* end of output flags */
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| 	FLAG_TWOBUFS = (1 << 9) * ENABLE_FEATURE_DD_IBS_OBS,
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| 	FLAG_COUNT   = 1 << 10,
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| 	FLAG_STATUS_NONE = 1 << 11,
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| 	FLAG_STATUS_NOXFER = 1 << 12,
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| };
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| 
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| static void dd_output_status(int UNUSED_PARAM cur_signal)
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| {
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| #if ENABLE_FEATURE_DD_THIRD_STATUS_LINE
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| 	double seconds;
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| 	unsigned long long bytes_sec;
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| 	unsigned long long now_us = monotonic_us(); /* before fprintf */
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| #endif
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| 
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| 	/* Deliberately using %u, not %d */
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| 	fprintf(stderr, "%"OFF_FMT"u+%"OFF_FMT"u records in\n"
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| 			"%"OFF_FMT"u+%"OFF_FMT"u records out\n",
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| 			G.in_full, G.in_part,
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| 			G.out_full, G.out_part);
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| 
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| #if ENABLE_FEATURE_DD_THIRD_STATUS_LINE
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| # if ENABLE_FEATURE_DD_STATUS
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| 	if (G.flags & FLAG_STATUS_NOXFER) /* status=noxfer active? */
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| 		return;
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| 	//TODO: should status=none make dd stop reacting to USR1 entirely?
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| 	//So far we react to it (we print the stats),
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| 	//status=none only suppresses final, non-USR1 generated status message.
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| # endif
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| 	fprintf(stderr, "%llu bytes (%sB) copied, ",
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| 			G.total_bytes,
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| 			/* show fractional digit, use suffixes */
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| 			make_human_readable_str(G.total_bytes, 1, 0)
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| 	);
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| 	/* Corner cases:
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| 	 * ./busybox dd </dev/null >/dev/null
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| 	 * ./busybox dd bs=1M count=2000 </dev/zero >/dev/null
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| 	 * (echo DONE) | ./busybox dd >/dev/null
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| 	 * (sleep 1; echo DONE) | ./busybox dd >/dev/null
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| 	 */
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| 	seconds = (now_us - G.begin_time_us) / 1000000.0;
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| 	bytes_sec = G.total_bytes / seconds;
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| 	fprintf(stderr, "%f seconds, %sB/s\n",
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| 			seconds,
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| 			/* show fractional digit, use suffixes */
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| 			make_human_readable_str(bytes_sec, 1, 0)
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| 	);
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| #endif
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| }
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| 
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| static bool write_and_stats(const void *buf, size_t len, size_t obs,
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| 	const char *filename)
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| {
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| 	ssize_t n;
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| 
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| 	n = full_write(ofd, buf, len);
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| #if ENABLE_FEATURE_DD_THIRD_STATUS_LINE
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| 	if (n > 0)
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| 		G.total_bytes += n;
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| #endif
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| 	if ((size_t)n == obs) {
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| 		G.out_full++;
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| 		return 0;
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| 	}
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| 	if ((size_t)n == len) {
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| 		G.out_part++;
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| 		return 0;
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| 	}
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| 	/* n is < len (and possibly is -1).
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| 	 * Even if n >= 0, errno is usually set correctly.
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| 	 * For example, if writing to block device and getting ENOSPC,
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| 	 * full_write() first sees a short write, then tries to write
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| 	 * the remainder and gets errno set to ENOSPC.
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| 	 * It returns n > 0 (the amount which it did write).
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| 	 */
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| 	bb_perror_msg("error writing '%s'", filename);
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| 	return 1;
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| }
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| 
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| #if ENABLE_LFS
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| # define XATOU_SFX xatoull_sfx
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| #else
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| # define XATOU_SFX xatoul_sfx
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| #endif
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| 
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| #if ENABLE_FEATURE_DD_IBS_OBS
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| static int parse_comma_flags(char *val, const char *words, const char *error_in)
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| {
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| 	int flags = 0;
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| 	while (1) {
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| 		int n;
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| 		char *arg;
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| 		/* find ',', replace them with NUL so we can use val for
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| 		 * index_in_strings() without copying.
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| 		 * We rely on val being non-null, else strchr would fault.
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| 		 */
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| 		arg = strchr(val, ',');
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| 		if (arg)
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| 			*arg = '\0';
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| 		n = index_in_strings(words, val);
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| 		if (n < 0)
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| 			bb_error_msg_and_die(bb_msg_invalid_arg_to, val, error_in);
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| 		flags |= (1 << n);
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| 		if (!arg) /* no ',' left, so this was the last specifier */
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| 			break;
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| 		*arg = ','; /* to preserve ps listing */
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| 		val = arg + 1; /* skip this keyword and ',' */
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| 	}
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| 	return flags;
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| }
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| #endif
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| 
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| int dd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
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| int dd_main(int argc UNUSED_PARAM, char **argv)
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| {
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| 	static const char keywords[] ALIGN1 =
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| 		"bs\0""count\0""seek\0""skip\0""if\0""of\0"IF_FEATURE_DD_STATUS("status\0")
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| #if ENABLE_FEATURE_DD_IBS_OBS
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| 		"ibs\0""obs\0""conv\0""iflag\0""oflag\0"
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| #endif
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| 		;
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| #if ENABLE_FEATURE_DD_IBS_OBS
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| 	static const char conv_words[] ALIGN1 =
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| 		"notrunc\0""sync\0""noerror\0""fsync\0""swab\0";
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| 	static const char iflag_words[] ALIGN1 =
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| 		"skip_bytes\0""fullblock\0";
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| 	static const char oflag_words[] ALIGN1 =
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| 		"seek_bytes\0append\0";
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| #endif
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| #if ENABLE_FEATURE_DD_STATUS
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| 	static const char status_words[] ALIGN1 =
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| 		"none\0""noxfer\0";
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| #endif
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| 	enum {
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| 		OP_bs = 0,
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| 		OP_count,
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| 		OP_seek,
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| 		OP_skip,
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| 		OP_if,
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| 		OP_of,
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| 		IF_FEATURE_DD_STATUS(OP_status,)
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| #if ENABLE_FEATURE_DD_IBS_OBS
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| 		OP_ibs,
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| 		OP_obs,
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| 		OP_conv,
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| 		OP_iflag,
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| 		OP_oflag,
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| 		/* Must be in the same order as FLAG_XXX! */
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| 		OP_conv_notrunc = 0,
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| 		OP_conv_sync,
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| 		OP_conv_noerror,
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| 		OP_conv_fsync,
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| 		OP_conv_swab,
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| 	/* Unimplemented conv=XXX: */
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| 	//nocreat       do not create the output file
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| 	//excl          fail if the output file already exists
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| 	//fdatasync     physically write output file data before finishing
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| 	//lcase         change upper case to lower case
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| 	//ucase         change lower case to upper case
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| 	//block         pad newline-terminated records with spaces to cbs-size
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| 	//unblock       replace trailing spaces in cbs-size records with newline
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| 	//ascii         from EBCDIC to ASCII
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| 	//ebcdic        from ASCII to EBCDIC
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| 	//ibm           from ASCII to alternate EBCDIC
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| 	/* Partially implemented: */
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| 	//swab          swap every pair of input bytes: will abort on non-even reads
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| 		OP_iflag_skip_bytes,
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| 		OP_iflag_fullblock,
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| 		OP_oflag_seek_bytes,
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| #endif
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| 	};
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| 	smallint exitcode = EXIT_FAILURE;
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| 	int i;
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| 	size_t ibs = 512;
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| 	char *ibuf;
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| #if ENABLE_FEATURE_DD_IBS_OBS
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| 	size_t obs = 512;
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| 	char *obuf;
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| #else
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| # define obs  ibs
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| # define obuf ibuf
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| #endif
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| 	/* These are all zeroed at once! */
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| 	struct {
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| 		IF_FEATURE_DD_IBS_OBS(size_t ocount;)
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| 		ssize_t prev_read_size; /* for detecting swab failure */
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| 		off_t count;
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| 		off_t seek, skip;
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| 		const char *infile, *outfile;
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| 	} Z;
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| #define ocount  (Z.ocount )
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| #define prev_read_size (Z.prev_read_size)
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| #define count   (Z.count  )
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| #define seek    (Z.seek   )
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| #define skip    (Z.skip   )
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| #define infile  (Z.infile )
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| #define outfile (Z.outfile)
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| 
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| 	memset(&Z, 0, sizeof(Z));
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| 	INIT_G();
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| 	//fflush_all(); - is this needed because of NOEXEC?
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| 
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| 	for (i = 1; argv[i]; i++) {
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| 		int what;
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| 		char *val;
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| 		char *arg = argv[i];
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| 
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| #if ENABLE_DESKTOP
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| 		/* "dd --". NB: coreutils 6.9 will complain if they see
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| 		 * more than one of them. We wouldn't. */
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| 		if (arg[0] == '-' && arg[1] == '-' && arg[2] == '\0')
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| 			continue;
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| #endif
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| 		val = strchr(arg, '=');
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| 		if (val == NULL)
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| 			bb_show_usage();
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| 		*val = '\0';
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| 		what = index_in_strings(keywords, arg);
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| 		if (what < 0)
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| 			bb_show_usage();
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| 		/* *val = '='; - to preserve ps listing? */
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| 		val++;
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| #if ENABLE_FEATURE_DD_IBS_OBS
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| 		if (what == OP_ibs) {
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| 			/* Must fit into positive ssize_t */
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| 			ibs = xatoul_range_sfx(val, 1, ((size_t)-1L)/2, cwbkMG_suffixes);
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| 			/*continue;*/
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| 		}
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| 		if (what == OP_obs) {
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| 			obs = xatoul_range_sfx(val, 1, ((size_t)-1L)/2, cwbkMG_suffixes);
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| 			/*continue;*/
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| 		}
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| 		if (what == OP_conv) {
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| 			G.flags |= parse_comma_flags(val, conv_words, "conv");
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| 			/*continue;*/
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| 		}
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| 		if (what == OP_iflag) {
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| 			G.flags |= parse_comma_flags(val, iflag_words, "iflag") << FLAG_IFLAG_SHIFT;
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| 			/*continue;*/
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| 		}
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| 		if (what == OP_oflag) {
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| 			G.flags |= parse_comma_flags(val, oflag_words, "oflag") << FLAG_OFLAG_SHIFT;
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| 			/*continue;*/
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| 		}
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| #endif
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| 		if (what == OP_bs) {
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| 			ibs = xatoul_range_sfx(val, 1, ((size_t)-1L)/2, cwbkMG_suffixes);
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| 			obs = ibs;
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| 			/*continue;*/
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| 		}
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| 		/* These can be large: */
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| 		if (what == OP_count) {
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| 			G.flags |= FLAG_COUNT;
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| 			count = XATOU_SFX(val, cwbkMG_suffixes);
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| 			/*continue;*/
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| 		}
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| 		if (what == OP_seek) {
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| 			seek = XATOU_SFX(val, cwbkMG_suffixes);
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| 			/*continue;*/
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| 		}
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| 		if (what == OP_skip) {
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| 			skip = XATOU_SFX(val, cwbkMG_suffixes);
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| 			/*continue;*/
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| 		}
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| 		if (what == OP_if) {
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| 			infile = val;
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| 			/*continue;*/
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| 		}
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| 		if (what == OP_of) {
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| 			outfile = val;
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| 			/*continue;*/
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| 		}
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| #if ENABLE_FEATURE_DD_STATUS
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| 		if (what == OP_status) {
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| 			int n;
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| 			n = index_in_strings(status_words, val);
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| 			if (n < 0)
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| 				bb_error_msg_and_die(bb_msg_invalid_arg_to, val, "status");
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| 			G.flags |= FLAG_STATUS_NONE << n;
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| 			/*continue;*/
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| 		}
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| #endif
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| 	} /* end of "for (argv[i])" */
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| 
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| //XXX:FIXME for huge ibs or obs, malloc'ing them isn't the brightest idea ever
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| 	ibuf = xmalloc(ibs);
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| 	obuf = ibuf;
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| #if ENABLE_FEATURE_DD_IBS_OBS
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| 	if (ibs != obs) {
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| 		G.flags |= FLAG_TWOBUFS;
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| 		obuf = xmalloc(obs);
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| 	}
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| #endif
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| 
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| #if ENABLE_FEATURE_DD_SIGNAL_HANDLING
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| 	signal_SA_RESTART_empty_mask(SIGUSR1, dd_output_status);
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| #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) {
 | |
| 		int oflag = O_WRONLY | O_CREAT;
 | |
| 
 | |
| 		if (!seek && !(G.flags & FLAG_NOTRUNC))
 | |
| 			oflag |= O_TRUNC;
 | |
| 		if (G.flags & FLAG_APPEND)
 | |
| 			oflag |= O_APPEND;
 | |
| 
 | |
| 		xmove_fd(xopen(outfile, oflag), ofd);
 | |
| 
 | |
| 		if (seek && !(G.flags & FLAG_NOTRUNC)) {
 | |
| 			size_t blocksz = (G.flags & FLAG_SEEK_BYTES) ? 1 : obs;
 | |
| 			if (ftruncate(ofd, seek * blocksz) < 0) {
 | |
| 				struct stat st;
 | |
| 
 | |
| 				if (fstat(ofd, &st) < 0
 | |
| 				 || S_ISREG(st.st_mode)
 | |
| 				 || S_ISDIR(st.st_mode)
 | |
| 				) {
 | |
| 					goto die_outfile;
 | |
| 				}
 | |
| 			}
 | |
| 		}
 | |
| 	} else {
 | |
| 		outfile = bb_msg_standard_output;
 | |
| 	}
 | |
| 	if (skip) {
 | |
| 		size_t blocksz = (G.flags & FLAG_SKIP_BYTES) ? 1 : ibs;
 | |
| 		if (lseek(ifd, skip * blocksz, SEEK_CUR) < 0) {
 | |
| 			do {
 | |
| 				ssize_t n;
 | |
| #if ENABLE_FEATURE_DD_IBS_OBS
 | |
| 				if (G.flags & FLAG_FULLBLOCK)
 | |
| 					n = full_read(ifd, ibuf, blocksz);
 | |
| 				else
 | |
| #endif
 | |
| 					n = safe_read(ifd, ibuf, blocksz);
 | |
| 				if (n < 0)
 | |
| 					goto die_infile;
 | |
| 				if (n == 0)
 | |
| 					break;
 | |
| 			} while (--skip != 0);
 | |
| 		}
 | |
| 	}
 | |
| 	if (seek) {
 | |
| 		size_t blocksz = (G.flags & FLAG_SEEK_BYTES) ? 1 : obs;
 | |
| 		if (lseek(ofd, seek * blocksz, SEEK_CUR) < 0)
 | |
| 			goto die_outfile;
 | |
| 	}
 | |
| 
 | |
| 	while (!(G.flags & FLAG_COUNT) || (G.in_full + G.in_part != count)) {
 | |
| 		ssize_t n;
 | |
| #if ENABLE_FEATURE_DD_IBS_OBS
 | |
| 		if (G.flags & FLAG_FULLBLOCK)
 | |
| 			n = full_read(ifd, ibuf, ibs);
 | |
| 		else
 | |
| #endif
 | |
| 			n = safe_read(ifd, ibuf, ibs);
 | |
| 		if (n == 0)
 | |
| 			break;
 | |
| 		if (n < 0) {
 | |
| 			/* "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 (G.flags & FLAG_SYNC) {
 | |
| 				memset(ibuf + n, 0, ibs - n);
 | |
| 				n = ibs;
 | |
| 			}
 | |
| 		}
 | |
| #if ENABLE_FEATURE_DD_IBS_OBS
 | |
| 		if (G.flags & FLAG_TWOBUFS) {
 | |
| 			char *tmp = ibuf;
 | |
| 			while (n) {
 | |
| 				size_t d = obs - ocount;
 | |
| 				if (d > (size_t)n)
 | |
| 					d = n;
 | |
| 				memcpy(obuf + ocount, tmp, d);
 | |
| 				n -= d;
 | |
| 				tmp += d;
 | |
| 				ocount += d;
 | |
| 				if (ocount == obs) {
 | |
| 					if (write_and_stats(obuf, obs, obs, outfile))
 | |
| 						goto out_status;
 | |
| 					ocount = 0;
 | |
| 				}
 | |
| 			}
 | |
| 		} else
 | |
| #endif
 | |
| 		{
 | |
| 			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
 | |
| 	if (ocount != 0) {
 | |
| 		if (write_and_stats(obuf, ocount, obs, outfile))
 | |
| 			goto out_status;
 | |
| 	}
 | |
| #endif
 | |
| 	if (close(ifd) < 0) {
 | |
|  die_infile:
 | |
| 		bb_simple_perror_msg_and_die(infile);
 | |
| 	}
 | |
| 
 | |
| 	if (close(ofd) < 0) {
 | |
|  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);
 | |
| 	}
 | |
| 
 | |
| 	return exitcode;
 | |
| }
 | 
