xref: /freebsd/stand/libsa/printf.c (revision 8aac90f18aef7c9eea906c3ff9a001ca7b94f375)
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 /*
36  * Standaloneified version of the FreeBSD kernel printf family.
37  */
38 
39 #include <sys/types.h>
40 #include <sys/stddef.h>
41 #include <sys/stdint.h>
42 #include <limits.h>
43 #include <string.h>
44 #include "stand.h"
45 
46 /*
47  * Note that stdarg.h and the ANSI style va_start macro is used for both
48  * ANSI and traditional C compilers.
49  */
50 #include <machine/stdarg.h>
51 
52 #define MAXNBUF (sizeof(intmax_t) * CHAR_BIT + 1)
53 
54 typedef void (kvprintf_fn_t)(int, void *);
55 
56 static char	*ksprintn (char *buf, uintmax_t num, int base, int *len, int upper);
57 static int	kvprintf(char const *fmt, kvprintf_fn_t *func, void *arg, int radix, va_list ap);
58 
59 static void
60 putchar_wrapper(int cc, void *arg)
61 {
62 
63 	putchar(cc);
64 }
65 
66 int
67 printf(const char *fmt, ...)
68 {
69 	va_list ap;
70 	int retval;
71 
72 	va_start(ap, fmt);
73 	retval = kvprintf(fmt, putchar_wrapper, NULL, 10, ap);
74 	va_end(ap);
75 	return retval;
76 }
77 
78 int
79 vprintf(const char *fmt, va_list ap)
80 {
81 
82 	return (kvprintf(fmt, putchar_wrapper, NULL, 10, ap));
83 }
84 
85 int
86 sprintf(char *buf, const char *cfmt, ...)
87 {
88 	int retval;
89 	va_list ap;
90 
91 	va_start(ap, cfmt);
92 	retval = kvprintf(cfmt, NULL, (void *)buf, 10, ap);
93 	buf[retval] = '\0';
94 	va_end(ap);
95 	return retval;
96 }
97 
98 struct print_buf {
99 	char *buf;
100 	size_t size;
101 };
102 
103 static void
104 snprint_func(int ch, void *arg)
105 {
106 	struct print_buf *pbuf = arg;
107 
108 	if (pbuf->size < 2) {
109 		/*
110 		 * Reserve last buffer position for the terminating
111 		 * character:
112 		 */
113 		return;
114 	}
115 	*(pbuf->buf)++ = ch;
116 	pbuf->size--;
117 }
118 
119 int
120 asprintf(char **buf, const char *cfmt, ...)
121 {
122 	int retval;
123 	struct print_buf arg;
124 	va_list ap;
125 
126 	*buf = NULL;
127 	va_start(ap, cfmt);
128 	retval = kvprintf(cfmt, NULL, NULL, 10, ap);
129 	va_end(ap);
130 	if (retval <= 0)
131 		return (-1);
132 
133 	arg.size = retval + 1;
134 	arg.buf = *buf = malloc(arg.size);
135 	if (*buf == NULL)
136 		return (-1);
137 
138 	va_start(ap, cfmt);
139 	retval = kvprintf(cfmt, &snprint_func, &arg, 10, ap);
140 	va_end(ap);
141 
142 	if (arg.size >= 1)
143 		*(arg.buf)++ = 0;
144 	return (retval);
145 }
146 
147 int
148 snprintf(char *buf, size_t size, const char *cfmt, ...)
149 {
150 	int retval;
151 	va_list ap;
152 	struct print_buf arg;
153 
154 	arg.buf = buf;
155 	arg.size = size;
156 
157 	va_start(ap, cfmt);
158 	retval = kvprintf(cfmt, &snprint_func, &arg, 10, ap);
159 	va_end(ap);
160 
161 	if (arg.size >= 1)
162 		*(arg.buf)++ = 0;
163 	return retval;
164 }
165 
166 int
167 vsnprintf(char *buf, size_t size, const char *cfmt, va_list ap)
168 {
169 	struct print_buf arg;
170 	int retval;
171 
172 	arg.buf = buf;
173 	arg.size = size;
174 
175 	retval = kvprintf(cfmt, &snprint_func, &arg, 10, ap);
176 
177 	if (arg.size >= 1)
178 		*(arg.buf)++ = 0;
179 
180 	return (retval);
181 }
182 
183 int
184 vsprintf(char *buf, const char *cfmt, va_list ap)
185 {
186 	int	retval;
187 
188 	retval = kvprintf(cfmt, NULL, (void *)buf, 10, ap);
189 	buf[retval] = '\0';
190 
191 	return (retval);
192 }
193 
194 /*
195  * Put a NUL-terminated ASCII number (base <= 36) in a buffer in reverse
196  * order; return an optional length and a pointer to the last character
197  * written in the buffer (i.e., the first character of the string).
198  * The buffer pointed to by `nbuf' must have length >= MAXNBUF.
199  */
200 static char *
201 ksprintn(char *nbuf, uintmax_t num, int base, int *lenp, int upper)
202 {
203 	char *p, c;
204 
205 	p = nbuf;
206 	*p = '\0';
207 	do {
208 		c = hex2ascii(num % base);
209 		*++p = upper ? toupper(c) : c;
210 	} while (num /= base);
211 	if (lenp)
212 		*lenp = p - nbuf;
213 	return (p);
214 }
215 
216 /*
217  * Scaled down version of printf(3).
218  *
219  * Two additional formats:
220  *
221  * The format %b is supported to decode error registers.
222  * Its usage is:
223  *
224  *	printf("reg=%b\n", regval, "<base><arg>*");
225  *
226  * where <base> is the output base expressed as a control character, e.g.
227  * \10 gives octal; \20 gives hex.  Each arg is a sequence of characters,
228  * the first of which gives the bit number to be inspected (origin 1), and
229  * the next characters (up to a control character, i.e. a character <= 32),
230  * give the name of the register.  Thus:
231  *
232  *	kvprintf("reg=%b\n", 3, "\10\2BITTWO\1BITONE");
233  *
234  * would produce output:
235  *
236  *	reg=3<BITTWO,BITONE>
237  *
238  * XXX:  %D  -- Hexdump, takes pointer and separator string:
239  *		("%6D", ptr, ":")   -> XX:XX:XX:XX:XX:XX
240  *		("%*D", len, ptr, " " -> XX XX XX XX ...
241  */
242 static int
243 kvprintf(char const *fmt, kvprintf_fn_t *func, void *arg, int radix, va_list ap)
244 {
245 #define PCHAR(c) { \
246 	int cc = (c);				\
247 						\
248 	if (func) {				\
249 		(*func)(cc, arg);		\
250 	} else if (d != NULL) {			\
251 		*d++ = cc;			\
252 	}					\
253 	retval++;				\
254 	}
255 
256 	char nbuf[MAXNBUF];
257 	char *d;
258 	const char *p, *percent, *q;
259 	uint16_t *S;
260 	u_char *up;
261 	int ch, n;
262 	uintmax_t num;
263 	int base, lflag, qflag, tmp, width, ladjust, sharpflag, neg, sign, dot;
264 	int cflag, hflag, jflag, tflag, zflag;
265 	int dwidth, upper;
266 	char padc;
267 	int stop = 0, retval = 0;
268 
269 	TSENTER();
270 	num = 0;
271 	if (!func)
272 		d = (char *) arg;
273 	else
274 		d = NULL;
275 
276 	if (fmt == NULL)
277 		fmt = "(fmt null)\n";
278 
279 	if (radix < 2 || radix > 36)
280 		radix = 10;
281 
282 	for (;;) {
283 		padc = ' ';
284 		width = 0;
285 		while ((ch = (u_char)*fmt++) != '%' || stop) {
286 			if (ch == '\0') {
287 				TSEXIT();
288 				return (retval);
289 			}
290 			PCHAR(ch);
291 		}
292 		percent = fmt - 1;
293 		qflag = 0; lflag = 0; ladjust = 0; sharpflag = 0; neg = 0;
294 		sign = 0; dot = 0; dwidth = 0; upper = 0;
295 		cflag = 0; hflag = 0; jflag = 0; tflag = 0; zflag = 0;
296 reswitch:	switch (ch = (u_char)*fmt++) {
297 		case '.':
298 			dot = 1;
299 			goto reswitch;
300 		case '#':
301 			sharpflag = 1;
302 			goto reswitch;
303 		case '+':
304 			sign = 1;
305 			goto reswitch;
306 		case '-':
307 			ladjust = 1;
308 			goto reswitch;
309 		case '%':
310 			PCHAR(ch);
311 			break;
312 		case '*':
313 			if (!dot) {
314 				width = va_arg(ap, int);
315 				if (width < 0) {
316 					ladjust = !ladjust;
317 					width = -width;
318 				}
319 			} else {
320 				dwidth = va_arg(ap, int);
321 			}
322 			goto reswitch;
323 		case '0':
324 			if (!dot) {
325 				padc = '0';
326 				goto reswitch;
327 			}
328 		case '1': case '2': case '3': case '4':
329 		case '5': case '6': case '7': case '8': case '9':
330 				for (n = 0;; ++fmt) {
331 					n = n * 10 + ch - '0';
332 					ch = *fmt;
333 					if (ch < '0' || ch > '9')
334 						break;
335 				}
336 			if (dot)
337 				dwidth = n;
338 			else
339 				width = n;
340 			goto reswitch;
341 		case 'b':
342 			num = (u_int)va_arg(ap, int);
343 			p = va_arg(ap, char *);
344 			for (q = ksprintn(nbuf, num, *p++, NULL, 0); *q;)
345 				PCHAR(*q--);
346 
347 			if (num == 0)
348 				break;
349 
350 			for (tmp = 0; *p;) {
351 				n = *p++;
352 				if (num & (1 << (n - 1))) {
353 					PCHAR(tmp ? ',' : '<');
354 					for (; (n = *p) > ' '; ++p)
355 						PCHAR(n);
356 					tmp = 1;
357 				} else
358 					for (; *p > ' '; ++p)
359 						continue;
360 			}
361 			if (tmp)
362 				PCHAR('>');
363 			break;
364 		case 'c':
365 			PCHAR(va_arg(ap, int));
366 			break;
367 		case 'D':
368 			up = va_arg(ap, u_char *);
369 			p = va_arg(ap, char *);
370 			if (!width)
371 				width = 16;
372 			while(width--) {
373 				PCHAR(hex2ascii(*up >> 4));
374 				PCHAR(hex2ascii(*up & 0x0f));
375 				up++;
376 				if (width)
377 					for (q=p;*q;q++)
378 						PCHAR(*q);
379 			}
380 			break;
381 		case 'd':
382 		case 'i':
383 			base = 10;
384 			sign = 1;
385 			goto handle_sign;
386 		case 'h':
387 			if (hflag) {
388 				hflag = 0;
389 				cflag = 1;
390 			} else
391 				hflag = 1;
392 			goto reswitch;
393 		case 'j':
394 			jflag = 1;
395 			goto reswitch;
396 		case 'l':
397 			if (lflag) {
398 				lflag = 0;
399 				qflag = 1;
400 			} else
401 				lflag = 1;
402 			goto reswitch;
403 		case 'n':
404 			if (jflag)
405 				*(va_arg(ap, intmax_t *)) = retval;
406 			else if (qflag)
407 				*(va_arg(ap, quad_t *)) = retval;
408 			else if (lflag)
409 				*(va_arg(ap, long *)) = retval;
410 			else if (zflag)
411 				*(va_arg(ap, size_t *)) = retval;
412 			else if (hflag)
413 				*(va_arg(ap, short *)) = retval;
414 			else if (cflag)
415 				*(va_arg(ap, char *)) = retval;
416 			else
417 				*(va_arg(ap, int *)) = retval;
418 			break;
419 		case 'o':
420 			base = 8;
421 			goto handle_nosign;
422 		case 'p':
423 			base = 16;
424 			sharpflag = (width == 0);
425 			sign = 0;
426 			num = (uintptr_t)va_arg(ap, void *);
427 			goto number;
428 		case 'q':
429 			qflag = 1;
430 			goto reswitch;
431 		case 'r':
432 			base = radix;
433 			if (sign)
434 				goto handle_sign;
435 			goto handle_nosign;
436 		case 's':
437 			p = va_arg(ap, char *);
438 			if (p == NULL)
439 				p = "(null)";
440 			if (!dot)
441 				n = strlen (p);
442 			else
443 				for (n = 0; n < dwidth && p[n]; n++)
444 					continue;
445 
446 			width -= n;
447 
448 			if (!ladjust && width > 0)
449 				while (width--)
450 					PCHAR(padc);
451 			while (n--)
452 				PCHAR(*p++);
453 			if (ladjust && width > 0)
454 				while (width--)
455 					PCHAR(padc);
456 			break;
457 		case 'S':	/* Assume console can cope with wide chars */
458 			for (S = va_arg(ap, uint16_t *); *S != 0; S++)
459 				PCHAR(*S);
460  			break;
461 		case 't':
462 			tflag = 1;
463 			goto reswitch;
464 		case 'u':
465 			base = 10;
466 			goto handle_nosign;
467 		case 'X':
468 			upper = 1;
469 		case 'x':
470 			base = 16;
471 			goto handle_nosign;
472 		case 'y':
473 			base = 16;
474 			sign = 1;
475 			goto handle_sign;
476 		case 'z':
477 			zflag = 1;
478 			goto reswitch;
479 handle_nosign:
480 			sign = 0;
481 			if (jflag)
482 				num = va_arg(ap, uintmax_t);
483 			else if (qflag)
484 				num = va_arg(ap, u_quad_t);
485 			else if (tflag)
486 				num = va_arg(ap, ptrdiff_t);
487 			else if (lflag)
488 				num = va_arg(ap, u_long);
489 			else if (zflag)
490 				num = va_arg(ap, size_t);
491 			else if (hflag)
492 				num = (u_short)va_arg(ap, int);
493 			else if (cflag)
494 				num = (u_char)va_arg(ap, int);
495 			else
496 				num = va_arg(ap, u_int);
497 			goto number;
498 handle_sign:
499 			if (jflag)
500 				num = va_arg(ap, intmax_t);
501 			else if (qflag)
502 				num = va_arg(ap, quad_t);
503 			else if (tflag)
504 				num = va_arg(ap, ptrdiff_t);
505 			else if (lflag)
506 				num = va_arg(ap, long);
507 			else if (zflag)
508 				num = va_arg(ap, ssize_t);
509 			else if (hflag)
510 				num = (short)va_arg(ap, int);
511 			else if (cflag)
512 				num = (char)va_arg(ap, int);
513 			else
514 				num = va_arg(ap, int);
515 number:
516 			if (sign && (intmax_t)num < 0) {
517 				neg = 1;
518 				num = -(intmax_t)num;
519 			}
520 			p = ksprintn(nbuf, num, base, &n, upper);
521 			tmp = 0;
522 			if (sharpflag && num != 0) {
523 				if (base == 8)
524 					tmp++;
525 				else if (base == 16)
526 					tmp += 2;
527 			}
528 			if (neg)
529 				tmp++;
530 
531 			if (!ladjust && padc == '0')
532 				dwidth = width - tmp;
533 			width -= tmp + imax(dwidth, n);
534 			dwidth -= n;
535 			if (!ladjust)
536 				while (width-- > 0)
537 					PCHAR(' ');
538 			if (neg)
539 				PCHAR('-');
540 			if (sharpflag && num != 0) {
541 				if (base == 8) {
542 					PCHAR('0');
543 				} else if (base == 16) {
544 					PCHAR('0');
545 					PCHAR('x');
546 				}
547 			}
548 			while (dwidth-- > 0)
549 				PCHAR('0');
550 
551 			while (*p)
552 				PCHAR(*p--);
553 
554 			if (ladjust)
555 				while (width-- > 0)
556 					PCHAR(' ');
557 
558 			break;
559 		default:
560 			while (percent < fmt)
561 				PCHAR(*percent++);
562 			/*
563 			 * Since we ignore a formatting argument it is no
564 			 * longer safe to obey the remaining formatting
565 			 * arguments as the arguments will no longer match
566 			 * the format specs.
567 			 */
568 			stop = 1;
569 			break;
570 		}
571 	}
572 #undef PCHAR
573 }
574