xref: /freebsd/libexec/rtld-elf/rtld_printf.c (revision b1f9167f94059fd55c630891d359bcff987bd7eb)
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  * Copyright (c) 2011 Konstantin Belousov <kib@FreeBSD.org>
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  *
35  * $FreeBSD$
36  */
37 
38 #include <sys/param.h>
39 #include <inttypes.h>
40 #include <stdarg.h>
41 #include <stddef.h>
42 #include <string.h>
43 #include <unistd.h>
44 #include "rtld_printf.h"
45 
46 #define MAXNBUF	(sizeof(intmax_t) * NBBY + 1)
47 
48 #define	PRINT_METHOD_SNPRINTF	1
49 #define	PRINT_METHOD_WRITE	2
50 
51 struct snprintf_arg {
52 	int	method;
53 	char	*str;
54 	char	*buf;
55 	size_t	remain;
56 	size_t	buf_total;
57 	int	fd;
58 };
59 
60 static void
61 printf_out(struct snprintf_arg *info)
62 {
63 
64 	if (info->remain == info->buf_total)
65 		return;
66 	write(info->fd, info->buf, info->buf_total - info->remain);
67 	info->str = info->buf;
68 	info->remain = info->buf_total;
69 }
70 
71 static void
72 snprintf_func(int ch, struct snprintf_arg *const info)
73 {
74 
75 	switch (info->method) {
76 	case PRINT_METHOD_SNPRINTF:
77 		if (info->remain >= 2) {
78 			*info->str++ = ch;
79 			info->remain--;
80 		}
81 		break;
82 	case PRINT_METHOD_WRITE:
83 		if (info->remain > 0) {
84 			*info->str++ = ch;
85 			info->remain--;
86 		} else
87 			printf_out(info);
88 		break;
89 	}
90 }
91 
92 static char const hex2ascii_lower[] = "0123456789abcdefghijklmnopqrstuvwxyz";
93 static char const hex2ascii_upper[] = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
94 #define	hex2ascii(hex)	(hex2ascii_lower[hex])
95 #define	hex2ascii_upper(hex)	(hex2ascii_upper[hex])
96 
97 static __inline int
98 imax(int a, int b)
99 {
100 
101 	return (a > b ? a : b);
102 }
103 
104 static char *
105 ksprintn(char *nbuf, uintmax_t num, int base, int *lenp, int upper)
106 {
107 	char *p, c;
108 
109 	p = nbuf;
110 	*p = '\0';
111 	do {
112 		c = upper ? hex2ascii_upper(num % base) :
113 		    hex2ascii(num % base);
114 		*++p = c;
115 	} while (num /= base);
116 	if (lenp)
117 		*lenp = p - nbuf;
118 	return (p);
119 }
120 
121 static int
122 kvprintf(char const *fmt, struct snprintf_arg *arg, int radix, va_list ap)
123 {
124 #define PCHAR(c) snprintf_func((c), arg)
125 	char nbuf[MAXNBUF];
126 	const char *p, *percent, *q;
127 	u_char *up;
128 	int ch, n;
129 	uintmax_t num;
130 	int base, lflag, qflag, tmp, width, ladjust, sharpflag, neg, sign, dot;
131 	int cflag, hflag, jflag, tflag, zflag;
132 	int dwidth, upper;
133 	char padc;
134 	int stop = 0, retval = 0;
135 
136 	num = 0;
137 
138 	if (fmt == NULL)
139 		fmt = "(fmt null)\n";
140 
141 	if (radix < 2 || radix > 36)
142 		radix = 10;
143 
144 	for (;;) {
145 		padc = ' ';
146 		width = 0;
147 		while ((ch = (u_char)*fmt++) != '%' || stop) {
148 			if (ch == '\0')
149 				return (retval);
150 			PCHAR(ch);
151 		}
152 		percent = fmt - 1;
153 		qflag = 0; lflag = 0; ladjust = 0; sharpflag = 0; neg = 0;
154 		sign = 0; dot = 0; dwidth = 0; upper = 0;
155 		cflag = 0; hflag = 0; jflag = 0; tflag = 0; zflag = 0;
156 reswitch:	switch (ch = (u_char)*fmt++) {
157 		case '.':
158 			dot = 1;
159 			goto reswitch;
160 		case '#':
161 			sharpflag = 1;
162 			goto reswitch;
163 		case '+':
164 			sign = 1;
165 			goto reswitch;
166 		case '-':
167 			ladjust = 1;
168 			goto reswitch;
169 		case '%':
170 			PCHAR(ch);
171 			break;
172 		case '*':
173 			if (!dot) {
174 				width = va_arg(ap, int);
175 				if (width < 0) {
176 					ladjust = !ladjust;
177 					width = -width;
178 				}
179 			} else {
180 				dwidth = va_arg(ap, int);
181 			}
182 			goto reswitch;
183 		case '0':
184 			if (!dot) {
185 				padc = '0';
186 				goto reswitch;
187 			}
188 		case '1': case '2': case '3': case '4':
189 		case '5': case '6': case '7': case '8': case '9':
190 				for (n = 0;; ++fmt) {
191 					n = n * 10 + ch - '0';
192 					ch = *fmt;
193 					if (ch < '0' || ch > '9')
194 						break;
195 				}
196 			if (dot)
197 				dwidth = n;
198 			else
199 				width = n;
200 			goto reswitch;
201 		case 'b':
202 			num = (u_int)va_arg(ap, int);
203 			p = va_arg(ap, char *);
204 			for (q = ksprintn(nbuf, num, *p++, NULL, 0); *q;)
205 				PCHAR(*q--);
206 
207 			if (num == 0)
208 				break;
209 
210 			for (tmp = 0; *p;) {
211 				n = *p++;
212 				if (num & (1 << (n - 1))) {
213 					PCHAR(tmp ? ',' : '<');
214 					for (; (n = *p) > ' '; ++p)
215 						PCHAR(n);
216 					tmp = 1;
217 				} else
218 					for (; *p > ' '; ++p)
219 						continue;
220 			}
221 			if (tmp)
222 				PCHAR('>');
223 			break;
224 		case 'c':
225 			PCHAR(va_arg(ap, int));
226 			break;
227 		case 'D':
228 			up = va_arg(ap, u_char *);
229 			p = va_arg(ap, char *);
230 			if (!width)
231 				width = 16;
232 			while(width--) {
233 				PCHAR(hex2ascii(*up >> 4));
234 				PCHAR(hex2ascii(*up & 0x0f));
235 				up++;
236 				if (width)
237 					for (q=p;*q;q++)
238 						PCHAR(*q);
239 			}
240 			break;
241 		case 'd':
242 		case 'i':
243 			base = 10;
244 			sign = 1;
245 			goto handle_sign;
246 		case 'h':
247 			if (hflag) {
248 				hflag = 0;
249 				cflag = 1;
250 			} else
251 				hflag = 1;
252 			goto reswitch;
253 		case 'j':
254 			jflag = 1;
255 			goto reswitch;
256 		case 'l':
257 			if (lflag) {
258 				lflag = 0;
259 				qflag = 1;
260 			} else
261 				lflag = 1;
262 			goto reswitch;
263 		case 'n':
264 			if (jflag)
265 				*(va_arg(ap, intmax_t *)) = retval;
266 			else if (qflag)
267 				*(va_arg(ap, quad_t *)) = retval;
268 			else if (lflag)
269 				*(va_arg(ap, long *)) = retval;
270 			else if (zflag)
271 				*(va_arg(ap, size_t *)) = retval;
272 			else if (hflag)
273 				*(va_arg(ap, short *)) = retval;
274 			else if (cflag)
275 				*(va_arg(ap, char *)) = retval;
276 			else
277 				*(va_arg(ap, int *)) = retval;
278 			break;
279 		case 'o':
280 			base = 8;
281 			goto handle_nosign;
282 		case 'p':
283 			base = 16;
284 			sharpflag = (width == 0);
285 			sign = 0;
286 			num = (uintptr_t)va_arg(ap, void *);
287 			goto number;
288 		case 'q':
289 			qflag = 1;
290 			goto reswitch;
291 		case 'r':
292 			base = radix;
293 			if (sign)
294 				goto handle_sign;
295 			goto handle_nosign;
296 		case 's':
297 			p = va_arg(ap, char *);
298 			if (p == NULL)
299 				p = "(null)";
300 			if (!dot)
301 				n = strlen (p);
302 			else
303 				for (n = 0; n < dwidth && p[n]; n++)
304 					continue;
305 
306 			width -= n;
307 
308 			if (!ladjust && width > 0)
309 				while (width--)
310 					PCHAR(padc);
311 			while (n--)
312 				PCHAR(*p++);
313 			if (ladjust && width > 0)
314 				while (width--)
315 					PCHAR(padc);
316 			break;
317 		case 't':
318 			tflag = 1;
319 			goto reswitch;
320 		case 'u':
321 			base = 10;
322 			goto handle_nosign;
323 		case 'X':
324 			upper = 1;
325 		case 'x':
326 			base = 16;
327 			goto handle_nosign;
328 		case 'y':
329 			base = 16;
330 			sign = 1;
331 			goto handle_sign;
332 		case 'z':
333 			zflag = 1;
334 			goto reswitch;
335 handle_nosign:
336 			sign = 0;
337 			if (jflag)
338 				num = va_arg(ap, uintmax_t);
339 			else if (qflag)
340 				num = va_arg(ap, u_quad_t);
341 			else if (tflag)
342 				num = va_arg(ap, ptrdiff_t);
343 			else if (lflag)
344 				num = va_arg(ap, u_long);
345 			else if (zflag)
346 				num = va_arg(ap, size_t);
347 			else if (hflag)
348 				num = (u_short)va_arg(ap, int);
349 			else if (cflag)
350 				num = (u_char)va_arg(ap, int);
351 			else
352 				num = va_arg(ap, u_int);
353 			goto number;
354 handle_sign:
355 			if (jflag)
356 				num = va_arg(ap, intmax_t);
357 			else if (qflag)
358 				num = va_arg(ap, quad_t);
359 			else if (tflag)
360 				num = va_arg(ap, ptrdiff_t);
361 			else if (lflag)
362 				num = va_arg(ap, long);
363 			else if (zflag)
364 				num = va_arg(ap, ssize_t);
365 			else if (hflag)
366 				num = (short)va_arg(ap, int);
367 			else if (cflag)
368 				num = (char)va_arg(ap, int);
369 			else
370 				num = va_arg(ap, int);
371 number:
372 			if (sign && (intmax_t)num < 0) {
373 				neg = 1;
374 				num = -(intmax_t)num;
375 			}
376 			p = ksprintn(nbuf, num, base, &n, upper);
377 			tmp = 0;
378 			if (sharpflag && num != 0) {
379 				if (base == 8)
380 					tmp++;
381 				else if (base == 16)
382 					tmp += 2;
383 			}
384 			if (neg)
385 				tmp++;
386 
387 			if (!ladjust && padc == '0')
388 				dwidth = width - tmp;
389 			width -= tmp + imax(dwidth, n);
390 			dwidth -= n;
391 			if (!ladjust)
392 				while (width-- > 0)
393 					PCHAR(' ');
394 			if (neg)
395 				PCHAR('-');
396 			if (sharpflag && num != 0) {
397 				if (base == 8) {
398 					PCHAR('0');
399 				} else if (base == 16) {
400 					PCHAR('0');
401 					PCHAR('x');
402 				}
403 			}
404 			while (dwidth-- > 0)
405 				PCHAR('0');
406 
407 			while (*p)
408 				PCHAR(*p--);
409 
410 			if (ladjust)
411 				while (width-- > 0)
412 					PCHAR(' ');
413 
414 			break;
415 		default:
416 			while (percent < fmt)
417 				PCHAR(*percent++);
418 			/*
419 			 * Since we ignore an formatting argument it is no
420 			 * longer safe to obey the remaining formatting
421 			 * arguments as the arguments will no longer match
422 			 * the format specs.
423 			 */
424 			stop = 1;
425 			break;
426 		}
427 	}
428 #undef PCHAR
429 }
430 
431 int
432 rtld_snprintf(char *buf, size_t bufsize, const char *fmt, ...)
433 {
434 	va_list ap;
435 	int retval;
436 
437 	va_start(ap, fmt);
438 	retval = rtld_vsnprintf(buf, bufsize, fmt, ap);
439 	va_end(ap);
440 	return (retval);
441 }
442 
443 int
444 rtld_vsnprintf(char *buf, size_t bufsize, const char *fmt, va_list ap)
445 {
446 	struct snprintf_arg info;
447 	int retval;
448 
449 	info.method = PRINT_METHOD_SNPRINTF;
450 	info.buf = info.str = buf;
451 	info.buf_total = info.remain = bufsize;
452 	info.fd = -1;
453 	retval = kvprintf(fmt, &info, 10, ap);
454 	if (info.remain >= 1)
455 		*info.str++ = '\0';
456 	return (retval);
457 }
458 
459 int
460 rtld_vfdprintf(int fd, const char *fmt, va_list ap)
461 {
462 	char buf[512];
463 	struct snprintf_arg info;
464 	int retval;
465 
466 	info.method = PRINT_METHOD_WRITE;
467 	info.buf = info.str = buf;
468 	info.buf_total = info.remain = sizeof(buf);
469 	info.fd = fd;
470 	retval = kvprintf(fmt, &info, 10, ap);
471 	printf_out(&info);
472 	return (retval);
473 }
474 
475 int
476 rtld_fdprintf(int fd, const char *fmt, ...)
477 {
478 	va_list ap;
479 	int retval;
480 
481 	va_start(ap, fmt);
482 	retval = rtld_vfdprintf(fd, fmt, ap);
483 	va_end(ap);
484 	return (retval);
485 }
486 
487 void
488 rtld_fdputstr(int fd, const char *str)
489 {
490 
491 	write(fd, str, strlen(str));
492 }
493 
494 void
495 rtld_fdputchar(int fd, int c)
496 {
497 	char c1;
498 
499 	c1 = c;
500 	write(fd, &c1, 1);
501 }
502