xref: /freebsd/stand/libsa/printf.c (revision 4b9d6057)
1 /*-
2  * Copyright (c) 1986, 1988, 1991, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  * (c) UNIX System Laboratories, Inc.
5  * All or some portions of this file are derived from material licensed
6  * to the University of California by American Telephone and Telegraph
7  * Co. or Unix System Laboratories, Inc. and are reproduced herein with
8  * the permission of UNIX System Laboratories, Inc.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  */
34 
35 #include <sys/cdefs.h>
36 /*
37  * Standaloneified version of the FreeBSD kernel printf family.
38  */
39 
40 #include <sys/types.h>
41 #include <sys/stddef.h>
42 #include <sys/stdint.h>
43 #include <limits.h>
44 #include <string.h>
45 #include "stand.h"
46 
47 /*
48  * Note that stdarg.h and the ANSI style va_start macro is used for both
49  * ANSI and traditional C compilers.
50  */
51 #include <machine/stdarg.h>
52 
53 #define MAXNBUF (sizeof(intmax_t) * CHAR_BIT + 1)
54 
55 typedef void (kvprintf_fn_t)(int, void *);
56 
57 static char	*ksprintn (char *buf, uintmax_t num, int base, int *len, int upper);
58 static int	kvprintf(char const *fmt, kvprintf_fn_t *func, void *arg, int radix, va_list ap);
59 
60 static void
61 putchar_wrapper(int cc, void *arg)
62 {
63 
64 	putchar(cc);
65 }
66 
67 int
68 printf(const char *fmt, ...)
69 {
70 	va_list ap;
71 	int retval;
72 
73 	va_start(ap, fmt);
74 	retval = kvprintf(fmt, putchar_wrapper, NULL, 10, ap);
75 	va_end(ap);
76 	return retval;
77 }
78 
79 int
80 vprintf(const char *fmt, va_list ap)
81 {
82 
83 	return (kvprintf(fmt, putchar_wrapper, NULL, 10, ap));
84 }
85 
86 int
87 sprintf(char *buf, const char *cfmt, ...)
88 {
89 	int retval;
90 	va_list ap;
91 
92 	va_start(ap, cfmt);
93 	retval = kvprintf(cfmt, NULL, (void *)buf, 10, ap);
94 	buf[retval] = '\0';
95 	va_end(ap);
96 	return retval;
97 }
98 
99 struct print_buf {
100 	char *buf;
101 	size_t size;
102 };
103 
104 static void
105 snprint_func(int ch, void *arg)
106 {
107 	struct print_buf *pbuf = arg;
108 
109 	if (pbuf->size < 2) {
110 		/*
111 		 * Reserve last buffer position for the terminating
112 		 * character:
113 		 */
114 		return;
115 	}
116 	*(pbuf->buf)++ = ch;
117 	pbuf->size--;
118 }
119 
120 int
121 asprintf(char **buf, const char *cfmt, ...)
122 {
123 	int retval;
124 	struct print_buf arg;
125 	va_list ap;
126 
127 	*buf = NULL;
128 	va_start(ap, cfmt);
129 	retval = kvprintf(cfmt, NULL, NULL, 10, ap);
130 	va_end(ap);
131 	if (retval <= 0)
132 		return (-1);
133 
134 	arg.size = retval + 1;
135 	arg.buf = *buf = malloc(arg.size);
136 	if (*buf == NULL)
137 		return (-1);
138 
139 	va_start(ap, cfmt);
140 	retval = kvprintf(cfmt, &snprint_func, &arg, 10, ap);
141 	va_end(ap);
142 
143 	if (arg.size >= 1)
144 		*(arg.buf)++ = 0;
145 	return (retval);
146 }
147 
148 int
149 snprintf(char *buf, size_t size, const char *cfmt, ...)
150 {
151 	int retval;
152 	va_list ap;
153 	struct print_buf arg;
154 
155 	arg.buf = buf;
156 	arg.size = size;
157 
158 	va_start(ap, cfmt);
159 	retval = kvprintf(cfmt, &snprint_func, &arg, 10, ap);
160 	va_end(ap);
161 
162 	if (arg.size >= 1)
163 		*(arg.buf)++ = 0;
164 	return retval;
165 }
166 
167 int
168 vsnprintf(char *buf, size_t size, const char *cfmt, va_list ap)
169 {
170 	struct print_buf arg;
171 	int retval;
172 
173 	arg.buf = buf;
174 	arg.size = size;
175 
176 	retval = kvprintf(cfmt, &snprint_func, &arg, 10, ap);
177 
178 	if (arg.size >= 1)
179 		*(arg.buf)++ = 0;
180 
181 	return (retval);
182 }
183 
184 int
185 vsprintf(char *buf, const char *cfmt, va_list ap)
186 {
187 	int	retval;
188 
189 	retval = kvprintf(cfmt, NULL, (void *)buf, 10, ap);
190 	buf[retval] = '\0';
191 
192 	return (retval);
193 }
194 
195 /*
196  * Put a NUL-terminated ASCII number (base <= 36) in a buffer in reverse
197  * order; return an optional length and a pointer to the last character
198  * written in the buffer (i.e., the first character of the string).
199  * The buffer pointed to by `nbuf' must have length >= MAXNBUF.
200  */
201 static char *
202 ksprintn(char *nbuf, uintmax_t num, int base, int *lenp, int upper)
203 {
204 	char *p, c;
205 
206 	p = nbuf;
207 	*p = '\0';
208 	do {
209 		c = hex2ascii(num % base);
210 		*++p = upper ? toupper(c) : c;
211 	} while (num /= base);
212 	if (lenp)
213 		*lenp = p - nbuf;
214 	return (p);
215 }
216 
217 /*
218  * Scaled down version of printf(3).
219  *
220  * Two additional formats:
221  *
222  * The format %b is supported to decode error registers.
223  * Its usage is:
224  *
225  *	printf("reg=%b\n", regval, "<base><arg>*");
226  *
227  * where <base> is the output base expressed as a control character, e.g.
228  * \10 gives octal; \20 gives hex.  Each arg is a sequence of characters,
229  * the first of which gives the bit number to be inspected (origin 1), and
230  * the next characters (up to a control character, i.e. a character <= 32),
231  * give the name of the register.  Thus:
232  *
233  *	kvprintf("reg=%b\n", 3, "\10\2BITTWO\1BITONE");
234  *
235  * would produce output:
236  *
237  *	reg=3<BITTWO,BITONE>
238  *
239  * XXX:  %D  -- Hexdump, takes pointer and separator string:
240  *		("%6D", ptr, ":")   -> XX:XX:XX:XX:XX:XX
241  *		("%*D", len, ptr, " " -> XX XX XX XX ...
242  */
243 static int
244 kvprintf(char const *fmt, kvprintf_fn_t *func, void *arg, int radix, va_list ap)
245 {
246 #define PCHAR(c) { \
247 	int cc = (c);				\
248 						\
249 	if (func) {				\
250 		(*func)(cc, arg);		\
251 	} else if (d != NULL) {			\
252 		*d++ = cc;			\
253 	}					\
254 	retval++;				\
255 	}
256 
257 	char nbuf[MAXNBUF];
258 	char *d;
259 	const char *p, *percent, *q;
260 	uint16_t *S;
261 	u_char *up;
262 	int ch, n;
263 	uintmax_t num;
264 	int base, lflag, qflag, tmp, width, ladjust, sharpflag, neg, sign, dot;
265 	int cflag, hflag, jflag, tflag, zflag;
266 	int dwidth, upper;
267 	char padc;
268 	int stop = 0, retval = 0;
269 
270 	TSENTER();
271 	num = 0;
272 	if (!func)
273 		d = (char *) arg;
274 	else
275 		d = NULL;
276 
277 	if (fmt == NULL)
278 		fmt = "(fmt null)\n";
279 
280 	if (radix < 2 || radix > 36)
281 		radix = 10;
282 
283 	for (;;) {
284 		padc = ' ';
285 		width = 0;
286 		while ((ch = (u_char)*fmt++) != '%' || stop) {
287 			if (ch == '\0') {
288 				TSEXIT();
289 				return (retval);
290 			}
291 			PCHAR(ch);
292 		}
293 		percent = fmt - 1;
294 		qflag = 0; lflag = 0; ladjust = 0; sharpflag = 0; neg = 0;
295 		sign = 0; dot = 0; dwidth = 0; upper = 0;
296 		cflag = 0; hflag = 0; jflag = 0; tflag = 0; zflag = 0;
297 reswitch:	switch (ch = (u_char)*fmt++) {
298 		case '.':
299 			dot = 1;
300 			goto reswitch;
301 		case '#':
302 			sharpflag = 1;
303 			goto reswitch;
304 		case '+':
305 			sign = 1;
306 			goto reswitch;
307 		case '-':
308 			ladjust = 1;
309 			goto reswitch;
310 		case '%':
311 			PCHAR(ch);
312 			break;
313 		case '*':
314 			if (!dot) {
315 				width = va_arg(ap, int);
316 				if (width < 0) {
317 					ladjust = !ladjust;
318 					width = -width;
319 				}
320 			} else {
321 				dwidth = va_arg(ap, int);
322 			}
323 			goto reswitch;
324 		case '0':
325 			if (!dot) {
326 				padc = '0';
327 				goto reswitch;
328 			}
329 		case '1': case '2': case '3': case '4':
330 		case '5': case '6': case '7': case '8': case '9':
331 				for (n = 0;; ++fmt) {
332 					n = n * 10 + ch - '0';
333 					ch = *fmt;
334 					if (ch < '0' || ch > '9')
335 						break;
336 				}
337 			if (dot)
338 				dwidth = n;
339 			else
340 				width = n;
341 			goto reswitch;
342 		case 'b':
343 			num = (u_int)va_arg(ap, int);
344 			p = va_arg(ap, char *);
345 			for (q = ksprintn(nbuf, num, *p++, NULL, 0); *q;)
346 				PCHAR(*q--);
347 
348 			if (num == 0)
349 				break;
350 
351 			for (tmp = 0; *p;) {
352 				n = *p++;
353 				if (num & (1 << (n - 1))) {
354 					PCHAR(tmp ? ',' : '<');
355 					for (; (n = *p) > ' '; ++p)
356 						PCHAR(n);
357 					tmp = 1;
358 				} else
359 					for (; *p > ' '; ++p)
360 						continue;
361 			}
362 			if (tmp)
363 				PCHAR('>');
364 			break;
365 		case 'c':
366 			PCHAR(va_arg(ap, int));
367 			break;
368 		case 'D':
369 			up = va_arg(ap, u_char *);
370 			p = va_arg(ap, char *);
371 			if (!width)
372 				width = 16;
373 			while(width--) {
374 				PCHAR(hex2ascii(*up >> 4));
375 				PCHAR(hex2ascii(*up & 0x0f));
376 				up++;
377 				if (width)
378 					for (q=p;*q;q++)
379 						PCHAR(*q);
380 			}
381 			break;
382 		case 'd':
383 		case 'i':
384 			base = 10;
385 			sign = 1;
386 			goto handle_sign;
387 		case 'h':
388 			if (hflag) {
389 				hflag = 0;
390 				cflag = 1;
391 			} else
392 				hflag = 1;
393 			goto reswitch;
394 		case 'j':
395 			jflag = 1;
396 			goto reswitch;
397 		case 'l':
398 			if (lflag) {
399 				lflag = 0;
400 				qflag = 1;
401 			} else
402 				lflag = 1;
403 			goto reswitch;
404 		case 'n':
405 			if (jflag)
406 				*(va_arg(ap, intmax_t *)) = retval;
407 			else if (qflag)
408 				*(va_arg(ap, quad_t *)) = retval;
409 			else if (lflag)
410 				*(va_arg(ap, long *)) = retval;
411 			else if (zflag)
412 				*(va_arg(ap, size_t *)) = retval;
413 			else if (hflag)
414 				*(va_arg(ap, short *)) = retval;
415 			else if (cflag)
416 				*(va_arg(ap, char *)) = retval;
417 			else
418 				*(va_arg(ap, int *)) = retval;
419 			break;
420 		case 'o':
421 			base = 8;
422 			goto handle_nosign;
423 		case 'p':
424 			base = 16;
425 			sharpflag = (width == 0);
426 			sign = 0;
427 			num = (uintptr_t)va_arg(ap, void *);
428 			goto number;
429 		case 'q':
430 			qflag = 1;
431 			goto reswitch;
432 		case 'r':
433 			base = radix;
434 			if (sign)
435 				goto handle_sign;
436 			goto handle_nosign;
437 		case 's':
438 			p = va_arg(ap, char *);
439 			if (p == NULL)
440 				p = "(null)";
441 			if (!dot)
442 				n = strlen (p);
443 			else
444 				for (n = 0; n < dwidth && p[n]; n++)
445 					continue;
446 
447 			width -= n;
448 
449 			if (!ladjust && width > 0)
450 				while (width--)
451 					PCHAR(padc);
452 			while (n--)
453 				PCHAR(*p++);
454 			if (ladjust && width > 0)
455 				while (width--)
456 					PCHAR(padc);
457 			break;
458 		case 'S':	/* Assume console can cope with wide chars */
459 			for (S = va_arg(ap, uint16_t *); *S != 0; S++)
460 				PCHAR(*S);
461  			break;
462 		case 't':
463 			tflag = 1;
464 			goto reswitch;
465 		case 'u':
466 			base = 10;
467 			goto handle_nosign;
468 		case 'X':
469 			upper = 1;
470 		case 'x':
471 			base = 16;
472 			goto handle_nosign;
473 		case 'y':
474 			base = 16;
475 			sign = 1;
476 			goto handle_sign;
477 		case 'z':
478 			zflag = 1;
479 			goto reswitch;
480 handle_nosign:
481 			sign = 0;
482 			if (jflag)
483 				num = va_arg(ap, uintmax_t);
484 			else if (qflag)
485 				num = va_arg(ap, u_quad_t);
486 			else if (tflag)
487 				num = va_arg(ap, ptrdiff_t);
488 			else if (lflag)
489 				num = va_arg(ap, u_long);
490 			else if (zflag)
491 				num = va_arg(ap, size_t);
492 			else if (hflag)
493 				num = (u_short)va_arg(ap, int);
494 			else if (cflag)
495 				num = (u_char)va_arg(ap, int);
496 			else
497 				num = va_arg(ap, u_int);
498 			goto number;
499 handle_sign:
500 			if (jflag)
501 				num = va_arg(ap, intmax_t);
502 			else if (qflag)
503 				num = va_arg(ap, quad_t);
504 			else if (tflag)
505 				num = va_arg(ap, ptrdiff_t);
506 			else if (lflag)
507 				num = va_arg(ap, long);
508 			else if (zflag)
509 				num = va_arg(ap, ssize_t);
510 			else if (hflag)
511 				num = (short)va_arg(ap, int);
512 			else if (cflag)
513 				num = (char)va_arg(ap, int);
514 			else
515 				num = va_arg(ap, int);
516 number:
517 			if (sign && (intmax_t)num < 0) {
518 				neg = 1;
519 				num = -(intmax_t)num;
520 			}
521 			p = ksprintn(nbuf, num, base, &n, upper);
522 			tmp = 0;
523 			if (sharpflag && num != 0) {
524 				if (base == 8)
525 					tmp++;
526 				else if (base == 16)
527 					tmp += 2;
528 			}
529 			if (neg)
530 				tmp++;
531 
532 			if (!ladjust && padc == '0')
533 				dwidth = width - tmp;
534 			width -= tmp + imax(dwidth, n);
535 			dwidth -= n;
536 			if (!ladjust)
537 				while (width-- > 0)
538 					PCHAR(' ');
539 			if (neg)
540 				PCHAR('-');
541 			if (sharpflag && num != 0) {
542 				if (base == 8) {
543 					PCHAR('0');
544 				} else if (base == 16) {
545 					PCHAR('0');
546 					PCHAR('x');
547 				}
548 			}
549 			while (dwidth-- > 0)
550 				PCHAR('0');
551 
552 			while (*p)
553 				PCHAR(*p--);
554 
555 			if (ladjust)
556 				while (width-- > 0)
557 					PCHAR(' ');
558 
559 			break;
560 		default:
561 			while (percent < fmt)
562 				PCHAR(*percent++);
563 			/*
564 			 * Since we ignore a formatting argument it is no
565 			 * longer safe to obey the remaining formatting
566 			 * arguments as the arguments will no longer match
567 			 * the format specs.
568 			 */
569 			stop = 1;
570 			break;
571 		}
572 	}
573 #undef PCHAR
574 }
575