xref: /freebsd/bin/dd/args.c (revision 6780ab54325a71e7e70112b11657973edde8655e)
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 #endif /* not lint */
43 #include <sys/cdefs.h>
44 __FBSDID("$FreeBSD$");
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(const void *, const void *);
58 static int	c_conv(const void *, const void *);
59 static void	f_bs(char *);
60 static void	f_cbs(char *);
61 static void	f_conv(char *);
62 static void	f_count(char *);
63 static void	f_files(char *);
64 static void	f_ibs(char *);
65 static void	f_if(char *);
66 static void	f_obs(char *);
67 static void	f_of(char *);
68 static void	f_seek(char *);
69 static void	f_skip(char *);
70 static u_quad_t	get_num(const char *);
71 static off_t	get_off_t(const char *);
72 
73 static 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 
93 static char *oper;
94 
95 /*
96  * args -- parse JCL syntax of dd.
97  */
98 void
99 jcl(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 
174 static int
175 c_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 
182 static void
183 f_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 
193 static void
194 f_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 
204 static void
205 f_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 
218 static void
219 f_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 
227 static void
228 f_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 
240 static void
241 f_if(char *arg)
242 {
243 
244 	in.name = arg;
245 }
246 
247 static void
248 f_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 
260 static void
261 f_of(char *arg)
262 {
263 
264 	out.name = arg;
265 }
266 
267 static void
268 f_seek(char *arg)
269 {
270 
271 	out.offset = get_off_t(arg);
272 }
273 
274 static void
275 f_skip(char *arg)
276 {
277 
278 	in.offset = get_off_t(arg);
279 }
280 
281 static 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 
304 static void
305 f_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 
323 static int
324 c_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  */
343 static u_quad_t
344 get_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 	default:
375 		;
376 	}
377 
378 	if (mult != 0) {
379 		prevnum = num;
380 		num *= mult;
381 		/* Check for overflow. */
382 		if (num / mult != prevnum)
383 			goto erange;
384 		expr++;
385 	}
386 
387 	switch (*expr) {
388 		case '\0':
389 			break;
390 		case '*':			/* Backward compatible. */
391 		case 'x':
392 			mult = get_num(expr + 1);
393 			prevnum = num;
394 			num *= mult;
395 			if (num / mult == prevnum)
396 				break;
397 erange:
398 			errx(1, "%s: %s", oper, strerror(ERANGE));
399 		default:
400 			errx(1, "%s: illegal numeric value", oper);
401 	}
402 	return (num);
403 }
404 
405 /*
406  * Convert an expression of the following forms to an off_t.  This is the
407  * same as get_num(), but it uses signed numbers.
408  *
409  * The major problem here is that an off_t may not necessarily be a quad_t.
410  * The right thing to do would be to use intmax_t when available and then
411  * cast down to an off_t, if possible.
412  */
413 static off_t
414 get_off_t(const char *val)
415 {
416 	quad_t num, mult, prevnum;
417 	char *expr;
418 
419 	errno = 0;
420 	num = strtoq(val, &expr, 0);
421 	if (errno != 0)				/* Overflow or underflow. */
422 		err(1, "%s", oper);
423 
424 	if (expr == val)			/* No valid digits. */
425 		errx(1, "%s: illegal numeric value", oper);
426 
427 	mult = 0;
428 	switch (*expr) {
429 	case 'b':
430 		mult = 512;
431 		break;
432 	case 'k':
433 		mult = 1 << 10;
434 		break;
435 	case 'm':
436 		mult = 1 << 20;
437 		break;
438 	case 'g':
439 		mult = 1 << 30;
440 		break;
441 	case 'w':
442 		mult = sizeof(int);
443 		break;
444 	}
445 
446 	if (mult != 0) {
447 		prevnum = num;
448 		num *= mult;
449 		/* Check for overflow. */
450 		if ((prevnum > 0) != (num > 0) || num / mult != prevnum)
451 			goto erange;
452 		expr++;
453 	}
454 
455 	switch (*expr) {
456 		case '\0':
457 			break;
458 		case '*':			/* Backward compatible. */
459 		case 'x':
460 			mult = (quad_t)get_off_t(expr + 1);
461 			prevnum = num;
462 			num *= mult;
463 			if ((prevnum > 0) == (num > 0) && num / mult == prevnum)
464 				break;
465 erange:
466 			errx(1, "%s: %s", oper, strerror(ERANGE));
467 		default:
468 			errx(1, "%s: illegal numeric value", oper);
469 	}
470 	return (num);
471 }
472