busybox/coreutils/dd.c

/* vi: set sw=4 ts=4: */
/*
 * Mini dd implementation for busybox
 *
 *
 * Copyright (C) 2000,2001  Matt Kraai
 *
 * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
 */

#include <signal.h>  /* For FEATURE_DD_SIGNAL_HANDLING */
#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 },
	{ }
};

struct globals {
	off_t out_full, out_part, in_full, in_part;
};
#define G (*(struct globals*)&bb_common_bufsiz1)
/* We have to zero it out because of NOEXEC */
#define INIT_G() memset(&G, 0, sizeof(G))


static void dd_output_status(int UNUSED_PARAM cur_signal)
{
	/* 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);
}

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)
{
	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++;
	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,
		FLAG_SYNC    = 1 << 1,
		FLAG_NOERROR = 1 << 2,
		FLAG_FSYNC   = 1 << 3,
		/* end of conv flags */
		FLAG_TWOBUFS = 1 << 4,
		FLAG_COUNT   = 1 << 5,
	};
	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";
#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,
	/* 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
	//swab          swap every pair of input bytes
	//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
#endif
	};
	int exitcode = EXIT_FAILURE;
	size_t ibs = 512, obs = 512;
	ssize_t n, w;
	char *ibuf, *obuf;
	/* And these are all zeroed at once! */
	struct {
		int flags;
		size_t oc;
		off_t count;
		off_t seek, skip;
		const char *infile, *outfile;
	} Z;
#define flags   (Z.flags  )
#define oc      (Z.oc     )
#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(NULL); - is this needed because of NOEXEC?

#if ENABLE_FEATURE_DD_SIGNAL_HANDLING
	signal_SA_RESTART_empty_mask(SIGUSR1, dd_output_status);
#endif

	for (n = 1; argv[n]; n++) {
		int what;
		char *val;
		char *arg = argv[n];

#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) {
				/* 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';
				what = index_in_strings(conv_words, val);
				if (what < 0)
					bb_error_msg_and_die(bb_msg_invalid_arg, val, "conv");
				flags |= (1 << what);
				if (!arg) /* no ',' left, so this was the last specifier */
					break;
				/* *arg = ','; - to preserve ps listing? */
				val = arg + 1; /* skip this keyword and ',' */
			}
			continue; /* we trashed 'what', can't fall through */
		}
#endif
		if (what == OP_bs) {
			ibs = obs = xatoul_range_sfx(val, 1, ((size_t)-1L)/2, dd_suffixes);
			/*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[n])" */

//XXX:FIXME for huge ibs or obs, malloc'ing them isn't the brightest idea ever
	ibuf = obuf = xmalloc(ibs);
	if (ibs != obs) {
		flags |= FLAG_TWOBUFS;
		obuf = xmalloc(obs);
	}
	if (infile != NULL)
		xmove_fd(xopen(infile, O_RDONLY), ifd);
	else {
		infile = bb_msg_standard_input;
	}
	if (outfile != NULL) {
		int oflag = O_WRONLY | O_CREAT;

		if (!seek && !(flags & FLAG_NOTRUNC))
			oflag |= O_TRUNC;

		xmove_fd(xopen(outfile, oflag), ofd);

		if (seek && !(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))
					goto die_outfile;
			}
		}
	} else {
		outfile = bb_msg_standard_output;
	}
	if (skip) {
		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 * obs, SEEK_CUR) < 0)
			goto die_outfile;
	}

	while (!(flags & FLAG_COUNT) || (G.in_full + G.in_part != count)) {
		if (flags & FLAG_NOERROR) /* Pre-zero the buffer if conv=noerror */
			memset(ibuf, 0, ibs);
		n = safe_read(ifd, ibuf, ibs);
		if (n == 0)
			break;
		if (n < 0) {
			if (!(flags & FLAG_NOERROR))
				goto die_infile;
			n = ibs;
			bb_simple_perror_msg(infile);
		}
		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) {
		w = full_write_or_warn(obuf, oc, outfile);
		if (w < 0) goto out_status;
		if (w > 0) G.out_part++;
	}
	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:
	dd_output_status(0);

	return exitcode;
}
1	/* vi: set sw=4 ts=4: */
2	/*
3	* Mini dd implementation for busybox
4	*
5	*
6	* Copyright (C) 2000,2001 Matt Kraai
7	*
8	* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
9	*/
10
11	#include <signal.h> /* For FEATURE_DD_SIGNAL_HANDLING */
12	#include "libbb.h"
13
14	/* This is a NOEXEC applet. Be very careful! */
15
16
17	enum {
18	ifd = STDIN_FILENO,
19	ofd = STDOUT_FILENO,
20	};
21
22	static const struct suffix_mult dd_suffixes[] = {
23	{ "c", 1 },
24	{ "w", 2 },
25	{ "b", 512 },
26	{ "kD", 1000 },
27	{ "k", 1024 },
28	{ "K", 1024 }, /* compat with coreutils dd */
29	{ "MD", 1000000 },
30	{ "M", 1048576 },
31	{ "GD", 1000000000 },
32	{ "G", 1073741824 },
33	{ }
34	};
35
36	struct globals {
37	off_t out_full, out_part, in_full, in_part;
38	};
39	#define G ((struct globals)&bb_common_bufsiz1)
40	/* We have to zero it out because of NOEXEC */
41	#define INIT_G() memset(&G, 0, sizeof(G))
42
43
44	static void dd_output_status(int UNUSED_PARAM cur_signal)
45	{
46	/* Deliberately using %u, not %d */
47	fprintf(stderr, "%"OFF_FMT"u+%"OFF_FMT"u records in\n"
48	"%"OFF_FMT"u+%"OFF_FMT"u records out\n",
49	G.in_full, G.in_part,
50	G.out_full, G.out_part);
51	}
52
53	static ssize_t full_write_or_warn(const void *buf, size_t len,
54	const char *const filename)
55	{
56	ssize_t n = full_write(ofd, buf, len);
57	if (n < 0)
58	bb_perror_msg("writing '%s'", filename);
59	return n;
60	}
61
62	static bool write_and_stats(const void *buf, size_t len, size_t obs,
63	const char *filename)
64	{
65	ssize_t n = full_write_or_warn(buf, len, filename);
66	if (n < 0)
67	return 1;
68	if ((size_t)n == obs)
69	G.out_full++;
70	else if (n) /* > 0 */
71	G.out_part++;
72	return 0;
73	}
74
75	#if ENABLE_LFS
76	#define XATOU_SFX xatoull_sfx
77	#else
78	#define XATOU_SFX xatoul_sfx
79	#endif
80
81	int dd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
82	int dd_main(int argc UNUSED_PARAM, char **argv)
83	{
84	enum {
85	/* Must be in the same order as OP_conv_XXX! */
86	/* (see "flags \|= (1 << what)" below) */
87	FLAG_NOTRUNC = 1 << 0,
88	FLAG_SYNC = 1 << 1,
89	FLAG_NOERROR = 1 << 2,
90	FLAG_FSYNC = 1 << 3,
91	/* end of conv flags */
92	FLAG_TWOBUFS = 1 << 4,
93	FLAG_COUNT = 1 << 5,
94	};
95	static const char keywords[] ALIGN1 =
96	"bs\0""count\0""seek\0""skip\0""if\0""of\0"
97	#if ENABLE_FEATURE_DD_IBS_OBS
98	"ibs\0""obs\0""conv\0"
99	#endif
100	;
101	#if ENABLE_FEATURE_DD_IBS_OBS
102	static const char conv_words[] ALIGN1 =
103	"notrunc\0""sync\0""noerror\0""fsync\0";
104	#endif
105	enum {
106	OP_bs = 0,
107	OP_count,
108	OP_seek,
109	OP_skip,
110	OP_if,
111	OP_of,
112	#if ENABLE_FEATURE_DD_IBS_OBS
113	OP_ibs,
114	OP_obs,
115	OP_conv,
116	/* Must be in the same order as FLAG_XXX! */
117	OP_conv_notrunc = 0,
118	OP_conv_sync,
119	OP_conv_noerror,
120	OP_conv_fsync,
121	/* Unimplemented conv=XXX: */
122	//nocreat do not create the output file
123	//excl fail if the output file already exists
124	//fdatasync physically write output file data before finishing
125	//swab swap every pair of input bytes
126	//lcase change upper case to lower case
127	//ucase change lower case to upper case
128	//block pad newline-terminated records with spaces to cbs-size
129	//unblock replace trailing spaces in cbs-size records with newline
130	//ascii from EBCDIC to ASCII
131	//ebcdic from ASCII to EBCDIC
132	//ibm from ASCII to alternate EBCDIC
133	#endif
134	};
135	int exitcode = EXIT_FAILURE;
136	size_t ibs = 512, obs = 512;
137	ssize_t n, w;
138	char ibuf, obuf;
139	/* And these are all zeroed at once! */
140	struct {
141	int flags;
142	size_t oc;
143	off_t count;
144	off_t seek, skip;
145	const char infile, outfile;
146	} Z;
147	#define flags (Z.flags )
148	#define oc (Z.oc )
149	#define count (Z.count )
150	#define seek (Z.seek )
151	#define skip (Z.skip )
152	#define infile (Z.infile )
153	#define outfile (Z.outfile)
154
155	memset(&Z, 0, sizeof(Z));
156	INIT_G();
157	//fflush(NULL); - is this needed because of NOEXEC?
158
159	#if ENABLE_FEATURE_DD_SIGNAL_HANDLING
160	signal_SA_RESTART_empty_mask(SIGUSR1, dd_output_status);
161	#endif
162
163	for (n = 1; argv[n]; n++) {
164	int what;
165	char *val;
166	char *arg = argv[n];
167
168	#if ENABLE_DESKTOP
169	/* "dd --". NB: coreutils 6.9 will complain if they see
170	* more than one of them. We wouldn't. */
171	if (arg[0] == '-' && arg[1] == '-' && arg[2] == '\0')
172	continue;
173	#endif
174	val = strchr(arg, '=');
175	if (val == NULL)
176	bb_show_usage();
177	*val = '\0';
178	what = index_in_strings(keywords, arg);
179	if (what < 0)
180	bb_show_usage();
181	/* val = '='; - to preserve ps listing? /
182	val++;
183	#if ENABLE_FEATURE_DD_IBS_OBS
184	if (what == OP_ibs) {
185	/* Must fit into positive ssize_t */
186	ibs = xatoul_range_sfx(val, 1, ((size_t)-1L)/2, dd_suffixes);
187	/continue;/
188	}
189	if (what == OP_obs) {
190	obs = xatoul_range_sfx(val, 1, ((size_t)-1L)/2, dd_suffixes);
191	/continue;/
192	}
193	if (what == OP_conv) {
194	while (1) {
195	/* find ',', replace them with NUL so we can use val for
196	* index_in_strings() without copying.
197	* We rely on val being non-null, else strchr would fault.
198	*/
199	arg = strchr(val, ',');
200	if (arg)
201	*arg = '\0';
202	what = index_in_strings(conv_words, val);
203	if (what < 0)
204	bb_error_msg_and_die(bb_msg_invalid_arg, val, "conv");
205	flags \|= (1 << what);
206	if (!arg) /* no ',' left, so this was the last specifier */
207	break;
208	/* arg = ','; - to preserve ps listing? /
209	val = arg + 1; /* skip this keyword and ',' */
210	}
211	continue; /* we trashed 'what', can't fall through */
212	}
213	#endif
214	if (what == OP_bs) {
215	ibs = obs = xatoul_range_sfx(val, 1, ((size_t)-1L)/2, dd_suffixes);
216	/continue;/
217	}
218	/* These can be large: */
219	if (what == OP_count) {
220	flags \|= FLAG_COUNT;
221	count = XATOU_SFX(val, dd_suffixes);
222	/continue;/
223	}
224	if (what == OP_seek) {
225	seek = XATOU_SFX(val, dd_suffixes);
226	/continue;/
227	}
228	if (what == OP_skip) {
229	skip = XATOU_SFX(val, dd_suffixes);
230	/continue;/
231	}
232	if (what == OP_if) {
233	infile = val;
234	/continue;/
235	}
236	if (what == OP_of) {
237	outfile = val;
238	/continue;/
239	}
240	} /* end of "for (argv[n])" */
241
242	//XXX:FIXME for huge ibs or obs, malloc'ing them isn't the brightest idea ever
243	ibuf = obuf = xmalloc(ibs);
244	if (ibs != obs) {
245	flags \|= FLAG_TWOBUFS;
246	obuf = xmalloc(obs);
247	}
248	if (infile != NULL)
249	xmove_fd(xopen(infile, O_RDONLY), ifd);
250	else {
251	infile = bb_msg_standard_input;
252	}
253	if (outfile != NULL) {
254	int oflag = O_WRONLY \| O_CREAT;
255
256	if (!seek && !(flags & FLAG_NOTRUNC))
257	oflag \|= O_TRUNC;
258
259	xmove_fd(xopen(outfile, oflag), ofd);
260
261	if (seek && !(flags & FLAG_NOTRUNC)) {
262	if (ftruncate(ofd, seek * obs) < 0) {
263	struct stat st;
264
265	if (fstat(ofd, &st) < 0 \|\| S_ISREG(st.st_mode) \|\|
266	S_ISDIR(st.st_mode))
267	goto die_outfile;
268	}
269	}
270	} else {
271	outfile = bb_msg_standard_output;
272	}
273	if (skip) {
274	if (lseek(ifd, skip * ibs, SEEK_CUR) < 0) {
275	while (skip-- > 0) {
276	n = safe_read(ifd, ibuf, ibs);
277	if (n < 0)
278	goto die_infile;
279	if (n == 0)
280	break;
281	}
282	}
283	}
284	if (seek) {
285	if (lseek(ofd, seek * obs, SEEK_CUR) < 0)
286	goto die_outfile;
287	}
288
289	while (!(flags & FLAG_COUNT) \|\| (G.in_full + G.in_part != count)) {
290	if (flags & FLAG_NOERROR) /* Pre-zero the buffer if conv=noerror */
291	memset(ibuf, 0, ibs);
292	n = safe_read(ifd, ibuf, ibs);
293	if (n == 0)
294	break;
295	if (n < 0) {
296	if (!(flags & FLAG_NOERROR))
297	goto die_infile;
298	n = ibs;
299	bb_simple_perror_msg(infile);
300	}
301	if ((size_t)n == ibs)
302	G.in_full++;
303	else {
304	G.in_part++;
305	if (flags & FLAG_SYNC) {
306	memset(ibuf + n, '\0', ibs - n);
307	n = ibs;
308	}
309	}
310	if (flags & FLAG_TWOBUFS) {
311	char *tmp = ibuf;
312	while (n) {
313	size_t d = obs - oc;
314
315	if (d > (size_t)n)
316	d = n;
317	memcpy(obuf + oc, tmp, d);
318	n -= d;
319	tmp += d;
320	oc += d;
321	if (oc == obs) {
322	if (write_and_stats(obuf, obs, obs, outfile))
323	goto out_status;
324	oc = 0;
325	}
326	}
327	} else if (write_and_stats(ibuf, n, obs, outfile))
328	goto out_status;
329
330	if (flags & FLAG_FSYNC) {
331	if (fsync(ofd) < 0)
332	goto die_outfile;
333	}
334	}
335
336	if (ENABLE_FEATURE_DD_IBS_OBS && oc) {
337	w = full_write_or_warn(obuf, oc, outfile);
338	if (w < 0) goto out_status;
339	if (w > 0) G.out_part++;
340	}
341	if (close(ifd) < 0) {
342	die_infile:
343	bb_simple_perror_msg_and_die(infile);
344	}
345
346	if (close(ofd) < 0) {
347	die_outfile:
348	bb_simple_perror_msg_and_die(outfile);
349	}
350
351	exitcode = EXIT_SUCCESS;
352	out_status:
353	dd_output_status(0);
354
355	return exitcode;
356	}