args.c revision 264577 
1/*-
2 * Copyright (c) 1991, 1993, 1994
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * Keith Muller of the University of California, San Diego and Lance
7 * Visser of Convex Computer Corporation.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 * 4. Neither the name of the University nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34#ifndef lint
35#if 0
36static char sccsid[] = "@(#)args.c	8.3 (Berkeley) 4/2/94";
37#endif
38#endif /* not lint */
39#include <sys/cdefs.h>
40__FBSDID("$FreeBSD: stable/10/bin/dd/args.c 264577 2014-04-17 00:31:20Z delphij $");
41
42#include <sys/types.h>
43
44#include <err.h>
45#include <errno.h>
46#include <inttypes.h>
47#include <limits.h>
48#include <signal.h>
49#include <stdlib.h>
50#include <string.h>
51
52#include "dd.h"
53#include "extern.h"
54
55static int	c_arg(const void *, const void *);
56static int	c_conv(const void *, const void *);
57static void	f_bs(char *);
58static void	f_cbs(char *);
59static void	f_conv(char *);
60static void	f_count(char *);
61static void	f_files(char *);
62static void	f_fillchar(char *);
63static void	f_ibs(char *);
64static void	f_if(char *);
65static void	f_obs(char *);
66static void	f_of(char *);
67static void	f_seek(char *);
68static void	f_skip(char *);
69static void	f_status(char *);
70static uintmax_t get_num(const char *);
71static off_t	get_off_t(const char *);
72
73static const struct arg {
74	const char *name;
75	void (*f)(char *);
76	u_int set, noset;
77} args[] = {
78	{ "bs",		f_bs,		C_BS,	 C_BS|C_IBS|C_OBS|C_OSYNC },
79	{ "cbs",	f_cbs,		C_CBS,	 C_CBS },
80	{ "conv",	f_conv,		0,	 0 },
81	{ "count",	f_count,	C_COUNT, C_COUNT },
82	{ "files",	f_files,	C_FILES, C_FILES },
83	{ "fillchar",	f_fillchar,	C_FILL,	 C_FILL },
84	{ "ibs",	f_ibs,		C_IBS,	 C_BS|C_IBS },
85	{ "if",		f_if,		C_IF,	 C_IF },
86	{ "iseek",	f_skip,		C_SKIP,	 C_SKIP },
87	{ "obs",	f_obs,		C_OBS,	 C_BS|C_OBS },
88	{ "of",		f_of,		C_OF,	 C_OF },
89	{ "oseek",	f_seek,		C_SEEK,	 C_SEEK },
90	{ "seek",	f_seek,		C_SEEK,	 C_SEEK },
91	{ "skip",	f_skip,		C_SKIP,	 C_SKIP },
92	{ "status",	f_status,	C_STATUS,C_STATUS },
93};
94
95static char *oper;
96
97/*
98 * args -- parse JCL syntax of dd.
99 */
100void
101jcl(char **argv)
102{
103	struct arg *ap, tmp;
104	char *arg;
105
106	in.dbsz = out.dbsz = 512;
107
108	while ((oper = *++argv) != NULL) {
109		if ((oper = strdup(oper)) == NULL)
110			errx(1, "unable to allocate space for the argument \"%s\"", *argv);
111		if ((arg = strchr(oper, '=')) == NULL)
112			errx(1, "unknown operand %s", oper);
113		*arg++ = '\0';
114		if (!*arg)
115			errx(1, "no value specified for %s", oper);
116		tmp.name = oper;
117		if (!(ap = (struct arg *)bsearch(&tmp, args,
118		    sizeof(args)/sizeof(struct arg), sizeof(struct arg),
119		    c_arg)))
120			errx(1, "unknown operand %s", tmp.name);
121		if (ddflags & ap->noset)
122			errx(1, "%s: illegal argument combination or already set",
123			    tmp.name);
124		ddflags |= ap->set;
125		ap->f(arg);
126	}
127
128	/* Final sanity checks. */
129
130	if (ddflags & C_BS) {
131		/*
132		 * Bs is turned off by any conversion -- we assume the user
133		 * just wanted to set both the input and output block sizes
134		 * and didn't want the bs semantics, so we don't warn.
135		 */
136		if (ddflags & (C_BLOCK | C_LCASE | C_SWAB | C_UCASE |
137		    C_UNBLOCK))
138			ddflags &= ~C_BS;
139
140		/* Bs supersedes ibs and obs. */
141		if (ddflags & C_BS && ddflags & (C_IBS | C_OBS))
142			warnx("bs supersedes ibs and obs");
143	}
144
145	/*
146	 * Ascii/ebcdic and cbs implies block/unblock.
147	 * Block/unblock requires cbs and vice-versa.
148	 */
149	if (ddflags & (C_BLOCK | C_UNBLOCK)) {
150		if (!(ddflags & C_CBS))
151			errx(1, "record operations require cbs");
152		if (cbsz == 0)
153			errx(1, "cbs cannot be zero");
154		cfunc = ddflags & C_BLOCK ? block : unblock;
155	} else if (ddflags & C_CBS) {
156		if (ddflags & (C_ASCII | C_EBCDIC)) {
157			if (ddflags & C_ASCII) {
158				ddflags |= C_UNBLOCK;
159				cfunc = unblock;
160			} else {
161				ddflags |= C_BLOCK;
162				cfunc = block;
163			}
164		} else
165			errx(1, "cbs meaningless if not doing record operations");
166	} else
167		cfunc = def;
168
169	/*
170	 * Bail out if the calculation of a file offset would overflow.
171	 */
172	if (in.offset > OFF_MAX / (ssize_t)in.dbsz ||
173	    out.offset > OFF_MAX / (ssize_t)out.dbsz)
174		errx(1, "seek offsets cannot be larger than %jd",
175		    (intmax_t)OFF_MAX);
176}
177
178static int
179c_arg(const void *a, const void *b)
180{
181
182	return (strcmp(((const struct arg *)a)->name,
183	    ((const struct arg *)b)->name));
184}
185
186static void
187f_bs(char *arg)
188{
189	uintmax_t res;
190
191	res = get_num(arg);
192	if (res < 1 || res > SSIZE_MAX)
193		errx(1, "bs must be between 1 and %jd", (intmax_t)SSIZE_MAX);
194	in.dbsz = out.dbsz = (size_t)res;
195}
196
197static void
198f_cbs(char *arg)
199{
200	uintmax_t res;
201
202	res = get_num(arg);
203	if (res < 1 || res > SSIZE_MAX)
204		errx(1, "cbs must be between 1 and %jd", (intmax_t)SSIZE_MAX);
205	cbsz = (size_t)res;
206}
207
208static void
209f_count(char *arg)
210{
211	intmax_t res;
212
213	res = (intmax_t)get_num(arg);
214	if (res < 0)
215		errx(1, "count cannot be negative");
216	if (res == 0)
217		cpy_cnt = (uintmax_t)-1;
218	else
219		cpy_cnt = (uintmax_t)res;
220}
221
222static void
223f_files(char *arg)
224{
225
226	files_cnt = get_num(arg);
227	if (files_cnt < 1)
228		errx(1, "files must be between 1 and %jd", (uintmax_t)-1);
229}
230
231static void
232f_fillchar(char *arg)
233{
234
235	if (strlen(arg) != 1)
236		errx(1, "need exactly one fill char");
237
238	fill_char = arg[0];
239}
240
241static void
242f_ibs(char *arg)
243{
244	uintmax_t res;
245
246	if (!(ddflags & C_BS)) {
247		res = get_num(arg);
248		if (res < 1 || res > SSIZE_MAX)
249			errx(1, "ibs must be between 1 and %jd",
250			    (intmax_t)SSIZE_MAX);
251		in.dbsz = (size_t)res;
252	}
253}
254
255static void
256f_if(char *arg)
257{
258
259	in.name = arg;
260}
261
262static void
263f_obs(char *arg)
264{
265	uintmax_t res;
266
267	if (!(ddflags & C_BS)) {
268		res = get_num(arg);
269		if (res < 1 || res > SSIZE_MAX)
270			errx(1, "obs must be between 1 and %jd",
271			    (intmax_t)SSIZE_MAX);
272		out.dbsz = (size_t)res;
273	}
274}
275
276static void
277f_of(char *arg)
278{
279
280	out.name = arg;
281}
282
283static void
284f_seek(char *arg)
285{
286
287	out.offset = get_off_t(arg);
288}
289
290static void
291f_skip(char *arg)
292{
293
294	in.offset = get_off_t(arg);
295}
296
297static void
298f_status(char *arg)
299{
300
301	if (strcmp(arg, "none") == 0)
302		ddflags |= C_NOINFO;
303	else if (strcmp(arg, "noxfer") == 0)
304		ddflags |= C_NOXFER;
305	else
306		errx(1, "unknown status %s", arg);
307}
308
309static const struct conv {
310	const char *name;
311	u_int set, noset;
312	const u_char *ctab;
313} clist[] = {
314	{ "ascii",	C_ASCII,	C_EBCDIC,	e2a_POSIX },
315	{ "block",	C_BLOCK,	C_UNBLOCK,	NULL },
316	{ "ebcdic",	C_EBCDIC,	C_ASCII,	a2e_POSIX },
317	{ "ibm",	C_EBCDIC,	C_ASCII,	a2ibm_POSIX },
318	{ "lcase",	C_LCASE,	C_UCASE,	NULL },
319	{ "noerror",	C_NOERROR,	0,		NULL },
320	{ "notrunc",	C_NOTRUNC,	0,		NULL },
321	{ "oldascii",	C_ASCII,	C_EBCDIC,	e2a_32V },
322	{ "oldebcdic",	C_EBCDIC,	C_ASCII,	a2e_32V },
323	{ "oldibm",	C_EBCDIC,	C_ASCII,	a2ibm_32V },
324	{ "osync",	C_OSYNC,	C_BS,		NULL },
325	{ "pareven",	C_PAREVEN,	C_PARODD|C_PARSET|C_PARNONE, NULL},
326	{ "parnone",	C_PARNONE,	C_PARODD|C_PARSET|C_PAREVEN, NULL},
327	{ "parodd",	C_PARODD,	C_PAREVEN|C_PARSET|C_PARNONE, NULL},
328	{ "parset",	C_PARSET,	C_PARODD|C_PAREVEN|C_PARNONE, NULL},
329	{ "sparse",	C_SPARSE,	0,		NULL },
330	{ "swab",	C_SWAB,		0,		NULL },
331	{ "sync",	C_SYNC,		0,		NULL },
332	{ "ucase",	C_UCASE,	C_LCASE,	NULL },
333	{ "unblock",	C_UNBLOCK,	C_BLOCK,	NULL },
334};
335
336static void
337f_conv(char *arg)
338{
339	struct conv *cp, tmp;
340
341	while (arg != NULL) {
342		tmp.name = strsep(&arg, ",");
343		cp = bsearch(&tmp, clist, sizeof(clist) / sizeof(struct conv),
344		    sizeof(struct conv), c_conv);
345		if (cp == NULL)
346			errx(1, "unknown conversion %s", tmp.name);
347		if (ddflags & cp->noset)
348			errx(1, "%s: illegal conversion combination", tmp.name);
349		ddflags |= cp->set;
350		if (cp->ctab)
351			ctab = cp->ctab;
352	}
353}
354
355static int
356c_conv(const void *a, const void *b)
357{
358
359	return (strcmp(((const struct conv *)a)->name,
360	    ((const struct conv *)b)->name));
361}
362
363/*
364 * Convert an expression of the following forms to a uintmax_t.
365 * 	1) A positive decimal number.
366 *	2) A positive decimal number followed by a 'b' or 'B' (mult by 512).
367 *	3) A positive decimal number followed by a 'k' or 'K' (mult by 1 << 10).
368 *	4) A positive decimal number followed by a 'm' or 'M' (mult by 1 << 20).
369 *	5) A positive decimal number followed by a 'g' or 'G' (mult by 1 << 30).
370 *	5) A positive decimal number followed by a 'w' or 'W' (mult by sizeof int).
371 *	6) Two or more positive decimal numbers (with/without [BbKkMmGgWw])
372 *	   separated by 'x' or 'X' (also '*' for backwards compatibility),
373 *	   specifying the product of the indicated values.
374 */
375static uintmax_t
376get_num(const char *val)
377{
378	uintmax_t num, mult, prevnum;
379	char *expr;
380
381	errno = 0;
382	num = strtouq(val, &expr, 0);
383	if (errno != 0)				/* Overflow or underflow. */
384		err(1, "%s", oper);
385
386	if (expr == val)			/* No valid digits. */
387		errx(1, "%s: illegal numeric value", oper);
388
389	mult = 0;
390	switch (*expr) {
391	case 'B':
392	case 'b':
393		mult = 512;
394		break;
395	case 'K':
396	case 'k':
397		mult = 1 << 10;
398		break;
399	case 'M':
400	case 'm':
401		mult = 1 << 20;
402		break;
403	case 'G':
404	case 'g':
405		mult = 1 << 30;
406		break;
407	case 'W':
408	case 'w':
409		mult = sizeof(int);
410		break;
411	default:
412		;
413	}
414
415	if (mult != 0) {
416		prevnum = num;
417		num *= mult;
418		/* Check for overflow. */
419		if (num / mult != prevnum)
420			goto erange;
421		expr++;
422	}
423
424	switch (*expr) {
425		case '\0':
426			break;
427		case '*':			/* Backward compatible. */
428		case 'X':
429		case 'x':
430			mult = get_num(expr + 1);
431			prevnum = num;
432			num *= mult;
433			if (num / mult == prevnum)
434				break;
435erange:
436			errx(1, "%s: %s", oper, strerror(ERANGE));
437		default:
438			errx(1, "%s: illegal numeric value", oper);
439	}
440	return (num);
441}
442
443/*
444 * Convert an expression of the following forms to an off_t.  This is the
445 * same as get_num(), but it uses signed numbers.
446 *
447 * The major problem here is that an off_t may not necessarily be a intmax_t.
448 */
449static off_t
450get_off_t(const char *val)
451{
452	intmax_t num, mult, prevnum;
453	char *expr;
454
455	errno = 0;
456	num = strtoq(val, &expr, 0);
457	if (errno != 0)				/* Overflow or underflow. */
458		err(1, "%s", oper);
459
460	if (expr == val)			/* No valid digits. */
461		errx(1, "%s: illegal numeric value", oper);
462
463	mult = 0;
464	switch (*expr) {
465	case 'B':
466	case 'b':
467		mult = 512;
468		break;
469	case 'K':
470	case 'k':
471		mult = 1 << 10;
472		break;
473	case 'M':
474	case 'm':
475		mult = 1 << 20;
476		break;
477	case 'G':
478	case 'g':
479		mult = 1 << 30;
480		break;
481	case 'W':
482	case 'w':
483		mult = sizeof(int);
484		break;
485	}
486
487	if (mult != 0) {
488		prevnum = num;
489		num *= mult;
490		/* Check for overflow. */
491		if ((prevnum > 0) != (num > 0) || num / mult != prevnum)
492			goto erange;
493		expr++;
494	}
495
496	switch (*expr) {
497		case '\0':
498			break;
499		case '*':			/* Backward compatible. */
500		case 'X':
501		case 'x':
502			mult = (intmax_t)get_off_t(expr + 1);
503			prevnum = num;
504			num *= mult;
505			if ((prevnum > 0) == (num > 0) && num / mult == prevnum)
506				break;
507erange:
508			errx(1, "%s: %s", oper, strerror(ERANGE));
509		default:
510			errx(1, "%s: illegal numeric value", oper);
511	}
512	return (num);
513}
514