xref: /freebsd/bin/dd/args.c (revision f9218d3d4fd34f082473b3a021c6d4d109fb47cf)
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 <inttypes.h>
51 #include <limits.h>
52 #include <stdlib.h>
53 #include <string.h>
54 
55 #include "dd.h"
56 #include "extern.h"
57 
58 static int	c_arg(const void *, const void *);
59 static int	c_conv(const void *, const void *);
60 static void	f_bs(char *);
61 static void	f_cbs(char *);
62 static void	f_conv(char *);
63 static void	f_count(char *);
64 static void	f_files(char *);
65 static void	f_ibs(char *);
66 static void	f_if(char *);
67 static void	f_obs(char *);
68 static void	f_of(char *);
69 static void	f_seek(char *);
70 static void	f_skip(char *);
71 static uintmax_t get_num(const char *);
72 static off_t	get_off_t(const char *);
73 
74 static const struct arg {
75 	const char *name;
76 	void (*f)(char *);
77 	u_int set, noset;
78 } args[] = {
79 	{ "bs",		f_bs,		C_BS,	 C_BS|C_IBS|C_OBS|C_OSYNC },
80 	{ "cbs",	f_cbs,		C_CBS,	 C_CBS },
81 	{ "conv",	f_conv,		0,	 0 },
82 	{ "count",	f_count,	C_COUNT, C_COUNT },
83 	{ "files",	f_files,	C_FILES, C_FILES },
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 };
93 
94 static char *oper;
95 
96 /*
97  * args -- parse JCL syntax of dd.
98  */
99 void
100 jcl(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 > OFF_MAX / (ssize_t)in.dbsz ||
172 	    out.offset > OFF_MAX / (ssize_t)out.dbsz)
173 		errx(1, "seek offsets cannot be larger than %jd",
174 		    (intmax_t)OFF_MAX);
175 }
176 
177 static int
178 c_arg(const void *a, const void *b)
179 {
180 
181 	return (strcmp(((const struct arg *)a)->name,
182 	    ((const struct arg *)b)->name));
183 }
184 
185 static void
186 f_bs(char *arg)
187 {
188 	uintmax_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(char *arg)
198 {
199 	uintmax_t res;
200 
201 	res = get_num(arg);
202 	if (res < 1 || res > SSIZE_MAX)
203 		errx(1, "cbs must be between 1 and %d", SSIZE_MAX);
204 	cbsz = (size_t)res;
205 }
206 
207 static void
208 f_count(char *arg)
209 {
210 	intmax_t res;
211 
212 	res = (intmax_t)get_num(arg);
213 	if (res < 0)
214 		errx(1, "count cannot be negative");
215 	if (res == 0)
216 		cpy_cnt = (uintmax_t)-1;
217 	else
218 		cpy_cnt = (uintmax_t)res;
219 }
220 
221 static void
222 f_files(char *arg)
223 {
224 
225 	files_cnt = get_num(arg);
226 	if (files_cnt < 1)
227 		errx(1, "files must be between 1 and %jd", (uintmax_t)-1);
228 }
229 
230 static void
231 f_ibs(char *arg)
232 {
233 	uintmax_t res;
234 
235 	if (!(ddflags & C_BS)) {
236 		res = get_num(arg);
237 		if (res < 1 || res > SSIZE_MAX)
238 			errx(1, "ibs must be between 1 and %zd", SSIZE_MAX);
239 		in.dbsz = (size_t)res;
240 	}
241 }
242 
243 static void
244 f_if(char *arg)
245 {
246 
247 	in.name = arg;
248 }
249 
250 static void
251 f_obs(char *arg)
252 {
253 	uintmax_t res;
254 
255 	if (!(ddflags & C_BS)) {
256 		res = get_num(arg);
257 		if (res < 1 || res > SSIZE_MAX)
258 			errx(1, "obs must be between 1 and %zd", SSIZE_MAX);
259 		out.dbsz = (size_t)res;
260 	}
261 }
262 
263 static void
264 f_of(char *arg)
265 {
266 
267 	out.name = arg;
268 }
269 
270 static void
271 f_seek(char *arg)
272 {
273 
274 	out.offset = get_off_t(arg);
275 }
276 
277 static void
278 f_skip(char *arg)
279 {
280 
281 	in.offset = get_off_t(arg);
282 }
283 
284 static const struct conv {
285 	const char *name;
286 	u_int set, noset;
287 	const u_char *ctab;
288 } clist[] = {
289 	{ "ascii",	C_ASCII,	C_EBCDIC,	e2a_POSIX },
290 	{ "block",	C_BLOCK,	C_UNBLOCK,	NULL },
291 	{ "ebcdic",	C_EBCDIC,	C_ASCII,	a2e_POSIX },
292 	{ "ibm",	C_EBCDIC,	C_ASCII,	a2ibm_POSIX },
293 	{ "lcase",	C_LCASE,	C_UCASE,	NULL },
294 	{ "noerror",	C_NOERROR,	0,		NULL },
295 	{ "notrunc",	C_NOTRUNC,	0,		NULL },
296 	{ "oldascii",	C_ASCII,	C_EBCDIC,	e2a_32V },
297 	{ "oldebcdic",	C_EBCDIC,	C_ASCII,	a2e_32V },
298 	{ "oldibm",	C_EBCDIC,	C_ASCII,	a2ibm_32V },
299 	{ "osync",	C_OSYNC,	C_BS,		NULL },
300 	{ "sparse",	C_SPARSE,	0,		NULL },
301 	{ "swab",	C_SWAB,		0,		NULL },
302 	{ "sync",	C_SYNC,		0,		NULL },
303 	{ "ucase",	C_UCASE,	C_LCASE,	NULL },
304 	{ "unblock",	C_UNBLOCK,	C_BLOCK,	NULL },
305 };
306 
307 static void
308 f_conv(char *arg)
309 {
310 	struct conv *cp, tmp;
311 
312 	while (arg != NULL) {
313 		tmp.name = strsep(&arg, ",");
314 		cp = bsearch(&tmp, clist, sizeof(clist) / sizeof(struct conv),
315 		    sizeof(struct conv), c_conv);
316 		if (cp == NULL)
317 			errx(1, "unknown conversion %s", tmp.name);
318 		if (ddflags & cp->noset)
319 			errx(1, "%s: illegal conversion combination", tmp.name);
320 		ddflags |= cp->set;
321 		if (cp->ctab)
322 			ctab = cp->ctab;
323 	}
324 }
325 
326 static int
327 c_conv(const void *a, const void *b)
328 {
329 
330 	return (strcmp(((const struct conv *)a)->name,
331 	    ((const struct conv *)b)->name));
332 }
333 
334 /*
335  * Convert an expression of the following forms to a uintmax_t.
336  * 	1) A positive decimal number.
337  *	2) A positive decimal number followed by a b (mult by 512).
338  *	3) A positive decimal number followed by a k (mult by 1 << 10).
339  *	4) A positive decimal number followed by a m (mult by 1 << 20).
340  *	5) A positive decimal number followed by a g (mult by 1 << 30).
341  *	5) A positive decimal number followed by a w (mult by sizeof int).
342  *	6) Two or more positive decimal numbers (with/without [bkmgw])
343  *	   separated by x (also * for backwards compatibility), specifying
344  *	   the product of the indicated values.
345  */
346 static uintmax_t
347 get_num(const char *val)
348 {
349 	uintmax_t num, mult, prevnum;
350 	char *expr;
351 
352 	errno = 0;
353 	num = strtouq(val, &expr, 0);
354 	if (errno != 0)				/* Overflow or underflow. */
355 		err(1, "%s", oper);
356 
357 	if (expr == val)			/* No valid digits. */
358 		errx(1, "%s: illegal numeric value", oper);
359 
360 	mult = 0;
361 	switch (*expr) {
362 	case 'b':
363 		mult = 512;
364 		break;
365 	case 'k':
366 		mult = 1 << 10;
367 		break;
368 	case 'm':
369 		mult = 1 << 20;
370 		break;
371 	case 'g':
372 		mult = 1 << 30;
373 		break;
374 	case 'w':
375 		mult = sizeof(int);
376 		break;
377 	default:
378 		;
379 	}
380 
381 	if (mult != 0) {
382 		prevnum = num;
383 		num *= mult;
384 		/* Check for overflow. */
385 		if (num / mult != prevnum)
386 			goto erange;
387 		expr++;
388 	}
389 
390 	switch (*expr) {
391 		case '\0':
392 			break;
393 		case '*':			/* Backward compatible. */
394 		case 'x':
395 			mult = get_num(expr + 1);
396 			prevnum = num;
397 			num *= mult;
398 			if (num / mult == prevnum)
399 				break;
400 erange:
401 			errx(1, "%s: %s", oper, strerror(ERANGE));
402 		default:
403 			errx(1, "%s: illegal numeric value", oper);
404 	}
405 	return (num);
406 }
407 
408 /*
409  * Convert an expression of the following forms to an off_t.  This is the
410  * same as get_num(), but it uses signed numbers.
411  *
412  * The major problem here is that an off_t may not necessarily be a intmax_t.
413  */
414 static off_t
415 get_off_t(const char *val)
416 {
417 	intmax_t num, mult, prevnum;
418 	char *expr;
419 
420 	errno = 0;
421 	num = strtoq(val, &expr, 0);
422 	if (errno != 0)				/* Overflow or underflow. */
423 		err(1, "%s", oper);
424 
425 	if (expr == val)			/* No valid digits. */
426 		errx(1, "%s: illegal numeric value", oper);
427 
428 	mult = 0;
429 	switch (*expr) {
430 	case 'b':
431 		mult = 512;
432 		break;
433 	case 'k':
434 		mult = 1 << 10;
435 		break;
436 	case 'm':
437 		mult = 1 << 20;
438 		break;
439 	case 'g':
440 		mult = 1 << 30;
441 		break;
442 	case 'w':
443 		mult = sizeof(int);
444 		break;
445 	}
446 
447 	if (mult != 0) {
448 		prevnum = num;
449 		num *= mult;
450 		/* Check for overflow. */
451 		if ((prevnum > 0) != (num > 0) || num / mult != prevnum)
452 			goto erange;
453 		expr++;
454 	}
455 
456 	switch (*expr) {
457 		case '\0':
458 			break;
459 		case '*':			/* Backward compatible. */
460 		case 'x':
461 			mult = (intmax_t)get_off_t(expr + 1);
462 			prevnum = num;
463 			num *= mult;
464 			if ((prevnum > 0) == (num > 0) && num / mult == prevnum)
465 				break;
466 erange:
467 			errx(1, "%s: %s", oper, strerror(ERANGE));
468 		default:
469 			errx(1, "%s: illegal numeric value", oper);
470 	}
471 	return (num);
472 }
473