args.c revision 90108 
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 * 3. All advertising materials mentioning features or use of this software
18 *    must display the following acknowledgement:
19 *	This product includes software developed by the University of
20 *	California, Berkeley and its contributors.
21 * 4. Neither the name of the University nor the names of its contributors
22 *    may be used to endorse or promote products derived from this software
23 *    without specific prior written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 * SUCH DAMAGE.
36 */
37
38#ifndef lint
39#if 0
40static char sccsid[] = "@(#)args.c	8.3 (Berkeley) 4/2/94";
41#endif
42static const char rcsid[] =
43  "$FreeBSD: head/bin/dd/args.c 90108 2002-02-02 06:24:13Z imp $";
44#endif /* not lint */
45
46#include <sys/types.h>
47
48#include <err.h>
49#include <errno.h>
50#include <limits.h>
51#include <stdlib.h>
52#include <string.h>
53
54#include "dd.h"
55#include "extern.h"
56
57static int	c_arg(const void *, const void *);
58static int	c_conv(const void *, const void *);
59static void	f_bs(char *);
60static void	f_cbs(char *);
61static void	f_conv(char *);
62static void	f_count(char *);
63static void	f_files(char *);
64static void	f_ibs(char *);
65static void	f_if(char *);
66static void	f_obs(char *);
67static void	f_of(char *);
68static void	f_seek(char *);
69static void	f_skip(char *);
70static u_quad_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	{ "ibs",	f_ibs,		C_IBS,	 C_BS|C_IBS },
84	{ "if",		f_if,		C_IF,	 C_IF },
85	{ "iseek",	f_skip,		C_SKIP,	 C_SKIP },
86	{ "obs",	f_obs,		C_OBS,	 C_BS|C_OBS },
87	{ "of",		f_of,		C_OF,	 C_OF },
88	{ "oseek",	f_seek,		C_SEEK,	 C_SEEK },
89	{ "seek",	f_seek,		C_SEEK,	 C_SEEK },
90	{ "skip",	f_skip,		C_SKIP,	 C_SKIP },
91};
92
93static char *oper;
94
95/*
96 * args -- parse JCL syntax of dd.
97 */
98void
99jcl(char **argv)
100{
101	struct arg *ap, tmp;
102	char *arg;
103
104	in.dbsz = out.dbsz = 512;
105
106	while ((oper = *++argv) != NULL) {
107		if ((oper = strdup(oper)) == NULL)
108			errx(1, "unable to allocate space for the argument \"%s\"", *argv);
109		if ((arg = strchr(oper, '=')) == NULL)
110			errx(1, "unknown operand %s", oper);
111		*arg++ = '\0';
112		if (!*arg)
113			errx(1, "no value specified for %s", oper);
114		tmp.name = oper;
115		if (!(ap = (struct arg *)bsearch(&tmp, args,
116		    sizeof(args)/sizeof(struct arg), sizeof(struct arg),
117		    c_arg)))
118			errx(1, "unknown operand %s", tmp.name);
119		if (ddflags & ap->noset)
120			errx(1, "%s: illegal argument combination or already set",
121			    tmp.name);
122		ddflags |= ap->set;
123		ap->f(arg);
124	}
125
126	/* Final sanity checks. */
127
128	if (ddflags & C_BS) {
129		/*
130		 * Bs is turned off by any conversion -- we assume the user
131		 * just wanted to set both the input and output block sizes
132		 * and didn't want the bs semantics, so we don't warn.
133		 */
134		if (ddflags & (C_BLOCK | C_LCASE | C_SWAB | C_UCASE |
135		    C_UNBLOCK))
136			ddflags &= ~C_BS;
137
138		/* Bs supersedes ibs and obs. */
139		if (ddflags & C_BS && ddflags & (C_IBS | C_OBS))
140			warnx("bs supersedes ibs and obs");
141	}
142
143	/*
144	 * Ascii/ebcdic and cbs implies block/unblock.
145	 * Block/unblock requires cbs and vice-versa.
146	 */
147	if (ddflags & (C_BLOCK | C_UNBLOCK)) {
148		if (!(ddflags & C_CBS))
149			errx(1, "record operations require cbs");
150		if (cbsz == 0)
151			errx(1, "cbs cannot be zero");
152		cfunc = ddflags & C_BLOCK ? block : unblock;
153	} else if (ddflags & C_CBS) {
154		if (ddflags & (C_ASCII | C_EBCDIC)) {
155			if (ddflags & C_ASCII) {
156				ddflags |= C_UNBLOCK;
157				cfunc = unblock;
158			} else {
159				ddflags |= C_BLOCK;
160				cfunc = block;
161			}
162		} else
163			errx(1, "cbs meaningless if not doing record operations");
164	} else
165		cfunc = def;
166
167	/*
168	 * Bail out if the calculation of a file offset would overflow.
169	 */
170	if (in.offset > QUAD_MAX / in.dbsz || out.offset > QUAD_MAX / out.dbsz)
171		errx(1, "seek offsets cannot be larger than %qd", QUAD_MAX);
172}
173
174static int
175c_arg(const void *a, const void *b)
176{
177
178	return (strcmp(((const struct arg *)a)->name,
179	    ((const struct arg *)b)->name));
180}
181
182static void
183f_bs(char *arg)
184{
185	u_quad_t res;
186
187	res = get_num(arg);
188	if (res < 1 || res > SSIZE_MAX)
189		errx(1, "bs must be between 1 and %d", SSIZE_MAX);
190	in.dbsz = out.dbsz = (size_t)res;
191}
192
193static void
194f_cbs(char *arg)
195{
196	u_quad_t res;
197
198	res = get_num(arg);
199	if (res < 1 || res > SSIZE_MAX)
200		errx(1, "cbs must be between 1 and %d", SSIZE_MAX);
201	cbsz = (size_t)res;
202}
203
204static void
205f_count(char *arg)
206{
207	u_quad_t res;
208
209	res = get_num(arg);
210	if ((quad_t)res < 0)
211		errx(1, "count cannot be negative");
212	if (res == 0)
213		cpy_cnt = -1;
214	else
215		cpy_cnt = (quad_t)res;
216}
217
218static void
219f_files(char *arg)
220{
221
222	files_cnt = get_num(arg);
223	if (files_cnt < 1)
224		errx(1, "files must be between 1 and %qd", QUAD_MAX);
225}
226
227static void
228f_ibs(char *arg)
229{
230	u_quad_t res;
231
232	if (!(ddflags & C_BS)) {
233		res = get_num(arg);
234		if (res < 1 || res > SSIZE_MAX)
235			errx(1, "ibs must be between 1 and %d", SSIZE_MAX);
236		in.dbsz = (size_t)res;
237	}
238}
239
240static void
241f_if(char *arg)
242{
243
244	in.name = arg;
245}
246
247static void
248f_obs(char *arg)
249{
250	u_quad_t res;
251
252	if (!(ddflags & C_BS)) {
253		res = get_num(arg);
254		if (res < 1 || res > SSIZE_MAX)
255			errx(1, "obs must be between 1 and %d", SSIZE_MAX);
256		out.dbsz = (size_t)res;
257	}
258}
259
260static void
261f_of(char *arg)
262{
263
264	out.name = arg;
265}
266
267static void
268f_seek(char *arg)
269{
270
271	out.offset = get_off_t(arg);
272}
273
274static void
275f_skip(char *arg)
276{
277
278	in.offset = get_off_t(arg);
279}
280
281static const struct conv {
282	const char *name;
283	u_int set, noset;
284	const u_char *ctab;
285} clist[] = {
286	{ "ascii",	C_ASCII,	C_EBCDIC,	e2a_POSIX },
287	{ "block",	C_BLOCK,	C_UNBLOCK,	NULL },
288	{ "ebcdic",	C_EBCDIC,	C_ASCII,	a2e_POSIX },
289	{ "ibm",	C_EBCDIC,	C_ASCII,	a2ibm_POSIX },
290	{ "lcase",	C_LCASE,	C_UCASE,	NULL },
291	{ "noerror",	C_NOERROR,	0,		NULL },
292	{ "notrunc",	C_NOTRUNC,	0,		NULL },
293	{ "oldascii",	C_ASCII,	C_EBCDIC,	e2a_32V },
294	{ "oldebcdic",	C_EBCDIC,	C_ASCII,	a2e_32V },
295	{ "oldibm",	C_EBCDIC,	C_ASCII,	a2ibm_32V },
296	{ "osync",	C_OSYNC,	C_BS,		NULL },
297	{ "sparse",	C_SPARSE,	0,		NULL },
298	{ "swab",	C_SWAB,		0,		NULL },
299	{ "sync",	C_SYNC,		0,		NULL },
300	{ "ucase",	C_UCASE,	C_LCASE,	NULL },
301	{ "unblock",	C_UNBLOCK,	C_BLOCK,	NULL },
302};
303
304static void
305f_conv(char *arg)
306{
307	struct conv *cp, tmp;
308
309	while (arg != NULL) {
310		tmp.name = strsep(&arg, ",");
311		cp = bsearch(&tmp, clist, sizeof(clist) / sizeof(struct conv),
312		    sizeof(struct conv), c_conv);
313		if (cp == NULL)
314			errx(1, "unknown conversion %s", tmp.name);
315		if (ddflags & cp->noset)
316			errx(1, "%s: illegal conversion combination", tmp.name);
317		ddflags |= cp->set;
318		if (cp->ctab)
319			ctab = cp->ctab;
320	}
321}
322
323static int
324c_conv(const void *a, const void *b)
325{
326
327	return (strcmp(((const struct conv *)a)->name,
328	    ((const struct conv *)b)->name));
329}
330
331/*
332 * Convert an expression of the following forms to a u_quad_t.
333 * 	1) A positive decimal number.
334 *	2) A positive decimal number followed by a b (mult by 512).
335 *	3) A positive decimal number followed by a k (mult by 1 << 10).
336 *	4) A positive decimal number followed by a m (mult by 1 << 20).
337 *	5) A positive decimal number followed by a g (mult by 1 << 30).
338 *	5) A positive decimal number followed by a w (mult by sizeof int).
339 *	6) Two or more positive decimal numbers (with/without [bkmgw])
340 *	   separated by x (also * for backwards compatibility), specifying
341 *	   the product of the indicated values.
342 */
343static u_quad_t
344get_num(const char *val)
345{
346	u_quad_t num, mult, prevnum;
347	char *expr;
348
349	errno = 0;
350	num = strtouq(val, &expr, 0);
351	if (errno != 0)				/* Overflow or underflow. */
352		err(1, "%s", oper);
353
354	if (expr == val)			/* No valid digits. */
355		errx(1, "%s: illegal numeric value", oper);
356
357	mult = 0;
358	switch (*expr) {
359	case 'b':
360		mult = 512;
361		break;
362	case 'k':
363		mult = 1 << 10;
364		break;
365	case 'm':
366		mult = 1 << 20;
367		break;
368	case 'g':
369		mult = 1 << 30;
370		break;
371	case 'w':
372		mult = sizeof(int);
373		break;
374	}
375
376	if (mult != 0) {
377		prevnum = num;
378		num *= mult;
379		/* Check for overflow. */
380		if (num / mult != prevnum)
381			goto erange;
382		expr++;
383	}
384
385	switch (*expr) {
386		case '\0':
387			break;
388		case '*':			/* Backward compatible. */
389		case 'x':
390			mult = get_num(expr + 1);
391			prevnum = num;
392			num *= mult;
393			if (num / mult == prevnum)
394				break;
395erange:
396			errx(1, "%s: %s", oper, strerror(ERANGE));
397		default:
398			errx(1, "%s: illegal numeric value", oper);
399	}
400	return (num);
401}
402
403/*
404 * Convert an expression of the following forms to an off_t.  This is the
405 * same as get_num(), but it uses signed numbers.
406 *
407 * The major problem here is that an off_t may not necessarily be a quad_t.
408 * The right thing to do would be to use intmax_t when available and then
409 * cast down to an off_t, if possible.
410 */
411static off_t
412get_off_t(const char *val)
413{
414	quad_t num, mult, prevnum;
415	char *expr;
416
417	errno = 0;
418	num = strtoq(val, &expr, 0);
419	if (errno != 0)				/* Overflow or underflow. */
420		err(1, "%s", oper);
421
422	if (expr == val)			/* No valid digits. */
423		errx(1, "%s: illegal numeric value", oper);
424
425	mult = 0;
426	switch (*expr) {
427	case 'b':
428		mult = 512;
429		break;
430	case 'k':
431		mult = 1 << 10;
432		break;
433	case 'm':
434		mult = 1 << 20;
435		break;
436	case 'g':
437		mult = 1 << 30;
438		break;
439	case 'w':
440		mult = sizeof(int);
441		break;
442	}
443
444	if (mult != 0) {
445		prevnum = num;
446		num *= mult;
447		/* Check for overflow. */
448		if ((prevnum > 0) != (num > 0) || num / mult != prevnum)
449			goto erange;
450		expr++;
451	}
452
453	switch (*expr) {
454		case '\0':
455			break;
456		case '*':			/* Backward compatible. */
457		case 'x':
458			mult = (quad_t)get_off_t(expr + 1);
459			prevnum = num;
460			num *= mult;
461			if ((prevnum > 0) != (num > 0) && num / mult == prevnum)
462				break;
463erange:
464			errx(1, "%s: %s", oper, strerror(ERANGE));
465		default:
466			errx(1, "%s: illegal numeric value", oper);
467	}
468	return (num);
469}
470