xref: /freebsd/bin/dd/args.c (revision 70fe064ad7cab6c0444b91622f60ec6a462f308a)
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
40 static char sccsid[] = "@(#)args.c	8.3 (Berkeley) 4/2/94";
41 #endif
42 static const char rcsid[] =
43   "$FreeBSD$";
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 
57 static int	c_arg __P((const void *, const void *));
58 static int	c_conv __P((const void *, const void *));
59 static void	f_bs __P((char *));
60 static void	f_cbs __P((char *));
61 static void	f_conv __P((char *));
62 static void	f_count __P((char *));
63 static void	f_files __P((char *));
64 static void	f_ibs __P((char *));
65 static void	f_if __P((char *));
66 static void	f_obs __P((char *));
67 static void	f_of __P((char *));
68 static void	f_seek __P((char *));
69 static void	f_skip __P((char *));
70 static u_quad_t	get_num __P((const char *));
71 static off_t	get_off_t __P((const char *));
72 
73 static const struct arg {
74 	const char *name;
75 	void (*f) __P((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 
93 static char *oper;
94 
95 /*
96  * args -- parse JCL syntax of dd.
97  */
98 void
99 jcl(argv)
100 	char **argv;
101 {
102 	struct arg *ap, tmp;
103 	char *arg;
104 
105 	in.dbsz = out.dbsz = 512;
106 
107 	while ((oper = *++argv) != NULL) {
108 		if ((oper = strdup(oper)) == NULL)
109 			errx(1, "unable to allocate space for the argument \"%s\"", *argv);
110 		if ((arg = strchr(oper, '=')) == NULL)
111 			errx(1, "unknown operand %s", oper);
112 		*arg++ = '\0';
113 		if (!*arg)
114 			errx(1, "no value specified for %s", oper);
115 		tmp.name = oper;
116 		if (!(ap = (struct arg *)bsearch(&tmp, args,
117 		    sizeof(args)/sizeof(struct arg), sizeof(struct arg),
118 		    c_arg)))
119 			errx(1, "unknown operand %s", tmp.name);
120 		if (ddflags & ap->noset)
121 			errx(1, "%s: illegal argument combination or already set",
122 			    tmp.name);
123 		ddflags |= ap->set;
124 		ap->f(arg);
125 	}
126 
127 	/* Final sanity checks. */
128 
129 	if (ddflags & C_BS) {
130 		/*
131 		 * Bs is turned off by any conversion -- we assume the user
132 		 * just wanted to set both the input and output block sizes
133 		 * and didn't want the bs semantics, so we don't warn.
134 		 */
135 		if (ddflags & (C_BLOCK | C_LCASE | C_SWAB | C_UCASE |
136 		    C_UNBLOCK))
137 			ddflags &= ~C_BS;
138 
139 		/* Bs supersedes ibs and obs. */
140 		if (ddflags & C_BS && ddflags & (C_IBS | C_OBS))
141 			warnx("bs supersedes ibs and obs");
142 	}
143 
144 	/*
145 	 * Ascii/ebcdic and cbs implies block/unblock.
146 	 * Block/unblock requires cbs and vice-versa.
147 	 */
148 	if (ddflags & (C_BLOCK | C_UNBLOCK)) {
149 		if (!(ddflags & C_CBS))
150 			errx(1, "record operations require cbs");
151 		if (cbsz == 0)
152 			errx(1, "cbs cannot be zero");
153 		cfunc = ddflags & C_BLOCK ? block : unblock;
154 	} else if (ddflags & C_CBS) {
155 		if (ddflags & (C_ASCII | C_EBCDIC)) {
156 			if (ddflags & C_ASCII) {
157 				ddflags |= C_UNBLOCK;
158 				cfunc = unblock;
159 			} else {
160 				ddflags |= C_BLOCK;
161 				cfunc = block;
162 			}
163 		} else
164 			errx(1, "cbs meaningless if not doing record operations");
165 	} else
166 		cfunc = def;
167 
168 	/*
169 	 * Bail out if the calculation of a file offset would overflow.
170 	 */
171 	if (in.offset > QUAD_MAX / in.dbsz || out.offset > QUAD_MAX / out.dbsz)
172 		errx(1, "seek offsets cannot be larger than %qd", QUAD_MAX);
173 }
174 
175 static int
176 c_arg(a, b)
177 	const void *a, *b;
178 {
179 
180 	return (strcmp(((const struct arg *)a)->name,
181 	    ((const struct arg *)b)->name));
182 }
183 
184 static void
185 f_bs(arg)
186 	char *arg;
187 {
188 	u_quad_t res;
189 
190 	res = get_num(arg);
191 	if (res < 1 || res > SSIZE_MAX)
192 		errx(1, "bs must be between 1 and %d", SSIZE_MAX);
193 	in.dbsz = out.dbsz = (size_t)res;
194 }
195 
196 static void
197 f_cbs(arg)
198 	char *arg;
199 {
200 	u_quad_t res;
201 
202 	res = get_num(arg);
203 	if (res < 1 || res > SSIZE_MAX)
204 		errx(1, "cbs must be between 1 and %d", SSIZE_MAX);
205 	cbsz = (size_t)res;
206 }
207 
208 static void
209 f_count(arg)
210 	char *arg;
211 {
212 	u_quad_t res;
213 
214 	res = get_num(arg);
215 	if ((quad_t)res < 0)
216 		errx(1, "count cannot be negative");
217 	if (res == 0)
218 		cpy_cnt = -1;
219 	else
220 		cpy_cnt = (quad_t)res;
221 }
222 
223 static void
224 f_files(arg)
225 	char *arg;
226 {
227 
228 	files_cnt = get_num(arg);
229 	if (files_cnt < 1)
230 		errx(1, "files must be between 1 and %qd", QUAD_MAX);
231 }
232 
233 static void
234 f_ibs(arg)
235 	char *arg;
236 {
237 	u_quad_t res;
238 
239 	if (!(ddflags & C_BS)) {
240 		res = get_num(arg);
241 		if (res < 1 || res > SSIZE_MAX)
242 			errx(1, "ibs must be between 1 and %d", SSIZE_MAX);
243 		in.dbsz = (size_t)res;
244 	}
245 }
246 
247 static void
248 f_if(arg)
249 	char *arg;
250 {
251 
252 	in.name = arg;
253 }
254 
255 static void
256 f_obs(arg)
257 	char *arg;
258 {
259 	u_quad_t res;
260 
261 	if (!(ddflags & C_BS)) {
262 		res = get_num(arg);
263 		if (res < 1 || res > SSIZE_MAX)
264 			errx(1, "obs must be between 1 and %d", SSIZE_MAX);
265 		out.dbsz = (size_t)res;
266 	}
267 }
268 
269 static void
270 f_of(arg)
271 	char *arg;
272 {
273 
274 	out.name = arg;
275 }
276 
277 static void
278 f_seek(arg)
279 	char *arg;
280 {
281 
282 	out.offset = get_off_t(arg);
283 }
284 
285 static void
286 f_skip(arg)
287 	char *arg;
288 {
289 
290 	in.offset = get_off_t(arg);
291 }
292 
293 static const struct conv {
294 	const char *name;
295 	u_int set, noset;
296 	const u_char *ctab;
297 } clist[] = {
298 	{ "ascii",	C_ASCII,	C_EBCDIC,	e2a_POSIX },
299 	{ "block",	C_BLOCK,	C_UNBLOCK,	NULL },
300 	{ "ebcdic",	C_EBCDIC,	C_ASCII,	a2e_POSIX },
301 	{ "ibm",	C_EBCDIC,	C_ASCII,	a2ibm_POSIX },
302 	{ "lcase",	C_LCASE,	C_UCASE,	NULL },
303 	{ "noerror",	C_NOERROR,	0,		NULL },
304 	{ "notrunc",	C_NOTRUNC,	0,		NULL },
305 	{ "oldascii",	C_ASCII,	C_EBCDIC,	e2a_32V },
306 	{ "oldebcdic",	C_EBCDIC,	C_ASCII,	a2e_32V },
307 	{ "oldibm",	C_EBCDIC,	C_ASCII,	a2ibm_32V },
308 	{ "osync",	C_OSYNC,	C_BS,		NULL },
309 	{ "sparse",	C_SPARSE,	0,		NULL },
310 	{ "swab",	C_SWAB,		0,		NULL },
311 	{ "sync",	C_SYNC,		0,		NULL },
312 	{ "ucase",	C_UCASE,	C_LCASE,	NULL },
313 	{ "unblock",	C_UNBLOCK,	C_BLOCK,	NULL },
314 };
315 
316 static void
317 f_conv(arg)
318 	char *arg;
319 {
320 	struct conv *cp, tmp;
321 
322 	while (arg != NULL) {
323 		tmp.name = strsep(&arg, ",");
324 		cp = bsearch(&tmp, clist, sizeof(clist) / sizeof(struct conv),
325 		    sizeof(struct conv), c_conv);
326 		if (cp == NULL)
327 			errx(1, "unknown conversion %s", tmp.name);
328 		if (ddflags & cp->noset)
329 			errx(1, "%s: illegal conversion combination", tmp.name);
330 		ddflags |= cp->set;
331 		if (cp->ctab)
332 			ctab = cp->ctab;
333 	}
334 }
335 
336 static int
337 c_conv(a, b)
338 	const void *a, *b;
339 {
340 
341 	return (strcmp(((const struct conv *)a)->name,
342 	    ((const struct conv *)b)->name));
343 }
344 
345 /*
346  * Convert an expression of the following forms to a u_quad_t.
347  * 	1) A positive decimal number.
348  *	2) A positive decimal number followed by a b (mult by 512).
349  *	3) A positive decimal number followed by a k (mult by 1 << 10).
350  *	4) A positive decimal number followed by a m (mult by 1 << 20).
351  *	5) A positive decimal number followed by a g (mult by 1 << 30).
352  *	5) A positive decimal number followed by a w (mult by sizeof int).
353  *	6) Two or more positive decimal numbers (with/without [bkmgw])
354  *	   separated by x (also * for backwards compatibility), specifying
355  *	   the product of the indicated values.
356  */
357 static u_quad_t
358 get_num(val)
359 	const char *val;
360 {
361 	u_quad_t num, mult, prevnum;
362 	char *expr;
363 
364 	errno = 0;
365 	num = strtouq(val, &expr, 0);
366 	if (errno != 0)				/* Overflow or underflow. */
367 		err(1, "%s", oper);
368 
369 	if (expr == val)			/* No valid digits. */
370 		errx(1, "%s: illegal numeric value", oper);
371 
372 	mult = 0;
373 	switch (*expr) {
374 	case 'b':
375 		mult = 512;
376 		break;
377 	case 'k':
378 		mult = 1 << 10;
379 		break;
380 	case 'm':
381 		mult = 1 << 20;
382 		break;
383 	case 'g':
384 		mult = 1 << 30;
385 		break;
386 	case 'w':
387 		mult = sizeof(int);
388 		break;
389 	}
390 
391 	if (mult != 0) {
392 		prevnum = num;
393 		num *= mult;
394 		/* Check for overflow. */
395 		if (num / mult != prevnum)
396 			goto erange;
397 		expr++;
398 	}
399 
400 	switch (*expr) {
401 		case '\0':
402 			break;
403 		case '*':			/* Backward compatible. */
404 		case 'x':
405 			mult = get_num(expr + 1);
406 			prevnum = num;
407 			num *= mult;
408 			if (num / mult == prevnum)
409 				break;
410 erange:
411 			errx(1, "%s: %s", oper, strerror(ERANGE));
412 		default:
413 			errx(1, "%s: illegal numeric value", oper);
414 	}
415 	return (num);
416 }
417 
418 /*
419  * Convert an expression of the following forms to an off_t.  This is the
420  * same as get_num(), but it uses signed numbers.
421  *
422  * The major problem here is that an off_t may not necessarily be a quad_t.
423  * The right thing to do would be to use intmax_t when available and then
424  * cast down to an off_t, if possible.
425  */
426 static off_t
427 get_off_t(val)
428 	const char *val;
429 {
430 	quad_t num, mult, prevnum;
431 	char *expr;
432 
433 	errno = 0;
434 	num = strtoq(val, &expr, 0);
435 	if (errno != 0)				/* Overflow or underflow. */
436 		err(1, "%s", oper);
437 
438 	if (expr == val)			/* No valid digits. */
439 		errx(1, "%s: illegal numeric value", oper);
440 
441 	mult = 0;
442 	switch (*expr) {
443 	case 'b':
444 		mult = 512;
445 		break;
446 	case 'k':
447 		mult = 1 << 10;
448 		break;
449 	case 'm':
450 		mult = 1 << 20;
451 		break;
452 	case 'g':
453 		mult = 1 << 30;
454 		break;
455 	case 'w':
456 		mult = sizeof(int);
457 		break;
458 	}
459 
460 	if (mult != 0) {
461 		prevnum = num;
462 		num *= mult;
463 		/* Check for overflow. */
464 		if ((prevnum > 0) != (num > 0) || num / mult != prevnum)
465 			goto erange;
466 		expr++;
467 	}
468 
469 	switch (*expr) {
470 		case '\0':
471 			break;
472 		case '*':			/* Backward compatible. */
473 		case 'x':
474 			mult = (quad_t)get_off_t(expr + 1);
475 			prevnum = num;
476 			num *= mult;
477 			if ((prevnum > 0) != (num > 0) && num / mult == prevnum)
478 				break;
479 erange:
480 			errx(1, "%s: %s", oper, strerror(ERANGE));
481 		default:
482 			errx(1, "%s: illegal numeric value", oper);
483 	}
484 	return (num);
485 }
486