xref: /freebsd/usr.bin/dc/inout.c (revision 1d386b48a555f61cb7325543adbbb5c3f3407a66)
1 /*	$OpenBSD: inout.c,v 1.18 2014/12/01 13:13:00 deraadt Exp $	*/
2 
3 /*
4  * Copyright (c) 2003, Otto Moerbeek <otto@drijf.net>
5  *
6  * Permission to use, copy, modify, and distribute this software for any
7  * purpose with or without fee is hereby granted, provided that the above
8  * copyright notice and this permission notice appear in all copies.
9  *
10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17  */
18 
19 #include <sys/cdefs.h>
20 #include <openssl/ssl.h>
21 #include <ctype.h>
22 #include <err.h>
23 #include <string.h>
24 
25 #include "extern.h"
26 
27 #define MAX_CHARS_PER_LINE 68
28 
29 static int	 lastchar;
30 static int	 charcount;
31 
32 static int	 src_getcharstream(struct source *);
33 static void	 src_ungetcharstream(struct source *);
34 static char	*src_getlinestream(struct source *);
35 static int	 src_getcharstring(struct source *);
36 static void	 src_ungetcharstring(struct source *);
37 static char	*src_getlinestring(struct source *);
38 static void	 src_freestring(struct source *);
39 static void	 flushwrap(FILE *);
40 static void	 putcharwrap(FILE *, int);
41 static void	 printwrap(FILE *, const char *);
42 static char	*get_digit(u_long, int, u_int);
43 
44 static struct vtable stream_vtable = {
45 	src_getcharstream,
46 	src_ungetcharstream,
47 	src_getlinestream,
48 	NULL
49 };
50 
51 static struct vtable string_vtable = {
52 	src_getcharstring,
53 	src_ungetcharstring,
54 	src_getlinestring,
55 	src_freestring
56 };
57 
58 void
src_setstream(struct source * src,FILE * stream)59 src_setstream(struct source *src, FILE *stream)
60 {
61 
62 	src->u.stream = stream;
63 	src->vtable = &stream_vtable;
64 }
65 
66 void
src_setstring(struct source * src,char * p)67 src_setstring(struct source *src, char *p)
68 {
69 
70 	src->u.string.buf = (u_char *)p;
71 	src->u.string.pos = 0;
72 	src->vtable = &string_vtable;
73 }
74 
75 static int
src_getcharstream(struct source * src)76 src_getcharstream(struct source *src)
77 {
78 
79 	return (src->lastchar = getc(src->u.stream));
80 }
81 
82 static void
src_ungetcharstream(struct source * src)83 src_ungetcharstream(struct source *src)
84 {
85 
86 	ungetc(src->lastchar, src->u.stream);
87 }
88 
89 static char *
src_getlinestream(struct source * src)90 src_getlinestream(struct source *src)
91 {
92 	char buf[BUFSIZ];
93 
94 	if (fgets(buf, BUFSIZ, src->u.stream) == NULL)
95 		return (bstrdup(""));
96 	return bstrdup(buf);
97 }
98 
99 static int
src_getcharstring(struct source * src)100 src_getcharstring(struct source *src)
101 {
102 
103 	src->lastchar = src->u.string.buf[src->u.string.pos];
104 	if (src->lastchar == '\0')
105 		return (EOF);
106 	else {
107 		src->u.string.pos++;
108 		return (src->lastchar);
109 	}
110 }
111 
112 static void
src_ungetcharstring(struct source * src)113 src_ungetcharstring(struct source *src)
114 {
115 
116 	if (src->u.string.pos > 0) {
117 		if (src->lastchar != '\0')
118 			--src->u.string.pos;
119 	}
120 }
121 
122 static char *
src_getlinestring(struct source * src)123 src_getlinestring(struct source *src)
124 {
125 	char buf[BUFSIZ];
126 	int i, ch;
127 
128 	i = 0;
129 	while (i < BUFSIZ-1) {
130 		ch = src_getcharstring(src);
131 		if (ch == EOF)
132 			break;
133 		buf[i++] = ch;
134 		if (ch == '\n')
135 			break;
136 	}
137 	buf[i] = '\0';
138 	return (bstrdup(buf));
139 }
140 
141 static void
src_freestring(struct source * src)142 src_freestring(struct source *src)
143 {
144 
145 	free(src->u.string.buf);
146 }
147 
148 static void
flushwrap(FILE * f)149 flushwrap(FILE *f)
150 {
151 
152 	if (lastchar != -1)
153 		putc(lastchar, f);
154 }
155 
156 static void
putcharwrap(FILE * f,int ch)157 putcharwrap(FILE *f, int ch)
158 {
159 
160 	if (charcount >= MAX_CHARS_PER_LINE) {
161 		charcount = 0;
162 		fputs("\\\n", f);
163 	}
164 	if (lastchar != -1) {
165 		charcount++;
166 		putc(lastchar, f);
167 	}
168 	lastchar = ch;
169 }
170 
171 static void
printwrap(FILE * f,const char * p)172 printwrap(FILE *f, const char *p)
173 {
174 	char *q;
175 	char buf[12];
176 
177 	q = buf;
178 	strlcpy(buf, p, sizeof(buf));
179 	while (*q)
180 		putcharwrap(f, *q++);
181 }
182 
183 struct number *
readnumber(struct source * src,u_int base,u_int bscale)184 readnumber(struct source *src, u_int base, u_int bscale)
185 {
186 	struct number *n;
187 	BN_ULONG v;
188 	int ch;
189 	u_int iscale = 0;
190 	bool dot = false, sign = false;
191 
192 	n = new_number();
193 	BN_zero(n->number);
194 
195 	while ((ch = (*src->vtable->readchar)(src)) != EOF) {
196 
197 		if ('0' <= ch && ch <= '9')
198 			v = ch - '0';
199 		else if ('A' <= ch && ch <= 'F')
200 			v = ch - 'A' + 10;
201 		else if (ch == '_') {
202 			sign = true;
203 			continue;
204 		} else if (ch == '.') {
205 			if (dot)
206 				break;
207 			dot = true;
208 			continue;
209 		} else {
210 			(*src->vtable->unreadchar)(src);
211 			break;
212 		}
213 		if (dot)
214 			iscale++;
215 
216 		bn_check(BN_mul_word(n->number, base));
217 		bn_check(BN_add_word(n->number, v));
218 	}
219 	if (base == 10) {
220 		n->scale = iscale;
221 	} else {
222 		/* At this point, the desired result is n->number / base^iscale*/
223 		struct number *quotient, *divisor, *_n;
224 		BIGNUM *base_n, *exponent;
225 		BN_CTX *ctx;
226 
227 		ctx = BN_CTX_new();
228 		base_n = BN_new();
229 		exponent = BN_new();
230 		divisor = new_number();
231 		BN_zero(base_n);
232 		BN_zero(exponent);
233 
234 		bn_check(BN_add_word(base_n, base));
235 		bn_check(BN_add_word(exponent, iscale));
236 		bn_check(BN_exp(divisor->number, base_n, exponent, ctx));
237 		divisor->scale = 0;
238 		quotient = div_number(n, divisor, bscale);
239 		_n = n;
240 		n = quotient;
241 
242 		/*
243 		 * Trim off trailing zeros to yield the smallest scale without
244 		 * loss of accuracy
245 		 */
246 		while ( n->scale > 0 &&
247 			BN_mod_word(n->number, 10) == 0) {
248 			normalize(n, n->scale - 1);
249 		}
250 
251 		free_number(_n);
252 		free_number(divisor);
253 		BN_CTX_free(ctx);
254 		BN_free(base_n);
255 		BN_free(exponent);
256 	}
257 	if (sign)
258 		negate(n);
259 	return (n);
260 }
261 
262 char *
read_string(struct source * src)263 read_string(struct source *src)
264 {
265 	char *p;
266 	int count, ch, i, new_sz, sz;
267 	bool escape;
268 
269 	escape = false;
270 	count = 1;
271 	i = 0;
272 	sz = 15;
273 	p = bmalloc(sz + 1);
274 
275 	while ((ch = (*src->vtable->readchar)(src)) != EOF) {
276 		if (!escape) {
277 			if (ch == '[')
278 				count++;
279 			else if (ch == ']')
280 				count--;
281 			if (count == 0)
282 				break;
283 		}
284 		if (ch == '\\' && !escape)
285 			escape = true;
286 		else {
287 			escape = false;
288 			if (i == sz) {
289 				new_sz = sz * 2;
290 				p = breallocarray(p, 1, new_sz + 1);
291 				sz = new_sz;
292 			}
293 			p[i++] = ch;
294 		}
295 	}
296 	p[i] = '\0';
297 	return (p);
298 }
299 
300 static char *
get_digit(u_long num,int digits,u_int base)301 get_digit(u_long num, int digits, u_int base)
302 {
303 	char *p;
304 
305 	if (base <= 16) {
306 		p = bmalloc(2);
307 		p[0] = num >= 10 ? num + 'A' - 10 : num + '0';
308 		p[1] = '\0';
309 	} else {
310 		if (asprintf(&p, "%0*lu", digits, num) == -1)
311 			err(1, NULL);
312 	}
313 	return (p);
314 }
315 
316 void
printnumber(FILE * f,const struct number * b,u_int base)317 printnumber(FILE *f, const struct number *b, u_int base)
318 {
319 	struct number *fract_part, *int_part;
320 	struct stack stack;
321 	char *p;
322 	char buf[11];
323 	size_t sz;
324 	unsigned int i;
325 	int digits;
326 
327 	charcount = 0;
328 	lastchar = -1;
329 	if (BN_is_zero(b->number))
330 		putcharwrap(f, '0');
331 
332 	int_part = new_number();
333 	fract_part = new_number();
334 	fract_part->scale = b->scale;
335 
336 	if (base <= 16)
337 		digits = 1;
338 	else {
339 		digits = snprintf(buf, sizeof(buf), "%u", base-1);
340 	}
341 	split_number(b, int_part->number, fract_part->number);
342 
343 	i = 0;
344 	stack_init(&stack);
345 	while (!BN_is_zero(int_part->number)) {
346 		BN_ULONG rem = BN_div_word(int_part->number, base);
347 		stack_pushstring(&stack, get_digit(rem, digits, base));
348 		i++;
349 	}
350 	sz = i;
351 	if (BN_is_negative(b->number))
352 		putcharwrap(f, '-');
353 	for (i = 0; i < sz; i++) {
354 		p = stack_popstring(&stack);
355 		if (base > 16)
356 			putcharwrap(f, ' ');
357 		printwrap(f, p);
358 		free(p);
359 	}
360 	stack_clear(&stack);
361 	if (b->scale > 0) {
362 		struct number *num_base;
363 		BIGNUM *mult, *stop;
364 
365 		putcharwrap(f, '.');
366 		num_base = new_number();
367 		bn_check(BN_set_word(num_base->number, base));
368 		mult = BN_new();
369 		bn_checkp(mult);
370 		bn_check(BN_one(mult));
371 		stop = BN_new();
372 		bn_checkp(stop);
373 		bn_check(BN_one(stop));
374 		scale_number(stop, b->scale);
375 
376 		i = 0;
377 		while (BN_cmp(mult, stop) < 0) {
378 			u_long rem;
379 
380 			if (i && base > 16)
381 				putcharwrap(f, ' ');
382 			i = 1;
383 
384 			bmul_number(fract_part, fract_part, num_base,
385 			    bmachine_scale());
386 			split_number(fract_part, int_part->number, NULL);
387 			rem = BN_get_word(int_part->number);
388 			p = get_digit(rem, digits, base);
389 			int_part->scale = 0;
390 			normalize(int_part, fract_part->scale);
391 			bn_check(BN_sub(fract_part->number, fract_part->number,
392 			    int_part->number));
393 			printwrap(f, p);
394 			free(p);
395 			bn_check(BN_mul_word(mult, base));
396 		}
397 		free_number(num_base);
398 		BN_free(mult);
399 		BN_free(stop);
400 	}
401 	flushwrap(f);
402 	free_number(int_part);
403 	free_number(fract_part);
404 }
405 
406 void
print_value(FILE * f,const struct value * value,const char * prefix,u_int base)407 print_value(FILE *f, const struct value *value, const char *prefix, u_int base)
408 {
409 
410 	fputs(prefix, f);
411 	switch (value->type) {
412 	case BCODE_NONE:
413 		if (value->array != NULL)
414 			fputs("<array>", f);
415 		break;
416 	case BCODE_NUMBER:
417 		printnumber(f, value->u.num, base);
418 		break;
419 	case BCODE_STRING:
420 		fputs(value->u.string, f);
421 		break;
422 	}
423 }
424 
425 void
print_ascii(FILE * f,const struct number * n)426 print_ascii(FILE *f, const struct number *n)
427 {
428 	BIGNUM *v;
429 	int ch, i, numbits;
430 
431 	v = BN_dup(n->number);
432 	bn_checkp(v);
433 
434 	if (BN_is_negative(v))
435 		BN_set_negative(v, 0);
436 
437 	numbits = BN_num_bytes(v) * 8;
438 	while (numbits > 0) {
439 		ch = 0;
440 		for (i = 0; i < 8; i++)
441 			ch |= BN_is_bit_set(v, numbits-i-1) << (7 - i);
442 		putc(ch, f);
443 		numbits -= 8;
444 	}
445 	BN_free(v);
446 }
447