xref: /freebsd/crypto/heimdal/lib/roken/snprintf.c (revision 1669d8afc64812c8d2d1d147ae1fd42ff441e1b1)
1 /*
2  * Copyright (c) 1995-2003 Kungliga Tekniska H�gskolan
3  * (Royal Institute of Technology, Stockholm, Sweden).
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  *
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  *
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * 3. Neither the name of the Institute nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #ifdef HAVE_CONFIG_H
35 #include <config.h>
36 RCSID("$Id: snprintf.c,v 1.35 2003/03/26 10:05:48 joda Exp $");
37 #endif
38 #include <stdio.h>
39 #include <stdarg.h>
40 #include <stdlib.h>
41 #include <string.h>
42 #include <ctype.h>
43 #include <roken.h>
44 
45 enum format_flags {
46     minus_flag     =  1,
47     plus_flag      =  2,
48     space_flag     =  4,
49     alternate_flag =  8,
50     zero_flag      = 16
51 };
52 
53 /*
54  * Common state
55  */
56 
57 struct snprintf_state {
58   unsigned char *str;
59   unsigned char *s;
60   unsigned char *theend;
61   size_t sz;
62   size_t max_sz;
63   void (*append_char)(struct snprintf_state *, unsigned char);
64   /* XXX - methods */
65 };
66 
67 #if TEST_SNPRINTF
68 #include "snprintf-test.h"
69 #endif /* TEST_SNPRINTF */
70 
71 #if !defined(HAVE_VSNPRINTF) || defined(TEST_SNPRINTF)
72 static int
73 sn_reserve (struct snprintf_state *state, size_t n)
74 {
75   return state->s + n > state->theend;
76 }
77 
78 static void
79 sn_append_char (struct snprintf_state *state, unsigned char c)
80 {
81   if (!sn_reserve (state, 1))
82     *state->s++ = c;
83 }
84 #endif
85 
86 static int
87 as_reserve (struct snprintf_state *state, size_t n)
88 {
89   if (state->s + n > state->theend) {
90     int off = state->s - state->str;
91     unsigned char *tmp;
92 
93     if (state->max_sz && state->sz >= state->max_sz)
94       return 1;
95 
96     state->sz = max(state->sz * 2, state->sz + n);
97     if (state->max_sz)
98       state->sz = min(state->sz, state->max_sz);
99     tmp = realloc (state->str, state->sz);
100     if (tmp == NULL)
101       return 1;
102     state->str = tmp;
103     state->s = state->str + off;
104     state->theend = state->str + state->sz - 1;
105   }
106   return 0;
107 }
108 
109 static void
110 as_append_char (struct snprintf_state *state, unsigned char c)
111 {
112   if(!as_reserve (state, 1))
113     *state->s++ = c;
114 }
115 
116 /* longest integer types */
117 
118 #ifdef HAVE_LONG_LONG
119 typedef unsigned long long u_longest;
120 typedef long long longest;
121 #else
122 typedef unsigned long u_longest;
123 typedef long longest;
124 #endif
125 
126 /*
127  * is # supposed to do anything?
128  */
129 
130 static int
131 use_alternative (int flags, u_longest num, unsigned base)
132 {
133   return flags & alternate_flag && (base == 16 || base == 8) && num != 0;
134 }
135 
136 static int
137 append_number(struct snprintf_state *state,
138 	      u_longest num, unsigned base, const char *rep,
139 	      int width, int prec, int flags, int minusp)
140 {
141   int len = 0;
142   int i;
143   u_longest n = num;
144 
145   /* given precision, ignore zero flag */
146   if(prec != -1)
147     flags &= ~zero_flag;
148   else
149     prec = 1;
150   /* zero value with zero precision -> "" */
151   if(prec == 0 && n == 0)
152     return 0;
153   do{
154     (*state->append_char)(state, rep[n % base]);
155     ++len;
156     n /= base;
157   } while(n);
158   prec -= len;
159   /* pad with prec zeros */
160   while(prec-- > 0){
161     (*state->append_char)(state, '0');
162     ++len;
163   }
164   /* add length of alternate prefix (added later) to len */
165   if(use_alternative(flags, num, base))
166     len += base / 8;
167   /* pad with zeros */
168   if(flags & zero_flag){
169     width -= len;
170     if(minusp || (flags & space_flag) || (flags & plus_flag))
171       width--;
172     while(width-- > 0){
173       (*state->append_char)(state, '0');
174       len++;
175     }
176   }
177   /* add alternate prefix */
178   if(use_alternative(flags, num, base)){
179     if(base == 16)
180       (*state->append_char)(state, rep[10] + 23); /* XXX */
181     (*state->append_char)(state, '0');
182   }
183   /* add sign */
184   if(minusp){
185     (*state->append_char)(state, '-');
186     ++len;
187   } else if(flags & plus_flag) {
188     (*state->append_char)(state, '+');
189     ++len;
190   } else if(flags & space_flag) {
191     (*state->append_char)(state, ' ');
192     ++len;
193   }
194   if(flags & minus_flag)
195     /* swap before padding with spaces */
196     for(i = 0; i < len / 2; i++){
197       char c = state->s[-i-1];
198       state->s[-i-1] = state->s[-len+i];
199       state->s[-len+i] = c;
200     }
201   width -= len;
202   while(width-- > 0){
203     (*state->append_char)(state,  ' ');
204     ++len;
205   }
206   if(!(flags & minus_flag))
207     /* swap after padding with spaces */
208     for(i = 0; i < len / 2; i++){
209       char c = state->s[-i-1];
210       state->s[-i-1] = state->s[-len+i];
211       state->s[-len+i] = c;
212     }
213   return len;
214 }
215 
216 /*
217  * return length
218  */
219 
220 static int
221 append_string (struct snprintf_state *state,
222 	       const unsigned char *arg,
223 	       int width,
224 	       int prec,
225 	       int flags)
226 {
227     int len = 0;
228 
229     if(arg == NULL)
230 	arg = (const unsigned char*)"(null)";
231 
232     if(prec != -1)
233 	width -= prec;
234     else
235 	width -= strlen((const char *)arg);
236     if(!(flags & minus_flag))
237 	while(width-- > 0) {
238 	    (*state->append_char) (state, ' ');
239 	    ++len;
240 	}
241     if (prec != -1) {
242 	while (*arg && prec--) {
243 	    (*state->append_char) (state, *arg++);
244 	    ++len;
245 	}
246     } else {
247 	while (*arg) {
248 	    (*state->append_char) (state, *arg++);
249 	    ++len;
250 	}
251     }
252     if(flags & minus_flag)
253 	while(width-- > 0) {
254 	    (*state->append_char) (state, ' ');
255 	    ++len;
256 	}
257     return len;
258 }
259 
260 static int
261 append_char(struct snprintf_state *state,
262 	    unsigned char arg,
263 	    int width,
264 	    int flags)
265 {
266   int len = 0;
267 
268   while(!(flags & minus_flag) && --width > 0) {
269     (*state->append_char) (state, ' ')    ;
270     ++len;
271   }
272   (*state->append_char) (state, arg);
273   ++len;
274   while((flags & minus_flag) && --width > 0) {
275     (*state->append_char) (state, ' ');
276     ++len;
277   }
278   return 0;
279 }
280 
281 /*
282  * This can't be made into a function...
283  */
284 
285 #ifdef HAVE_LONG_LONG
286 
287 #define PARSE_INT_FORMAT(res, arg, unsig) \
288 if (long_long_flag) \
289      res = (unsig long long)va_arg(arg, unsig long long); \
290 else if (long_flag) \
291      res = (unsig long)va_arg(arg, unsig long); \
292 else if (short_flag) \
293      res = (unsig short)va_arg(arg, unsig int); \
294 else \
295      res = (unsig int)va_arg(arg, unsig int)
296 
297 #else
298 
299 #define PARSE_INT_FORMAT(res, arg, unsig) \
300 if (long_flag) \
301      res = (unsig long)va_arg(arg, unsig long); \
302 else if (short_flag) \
303      res = (unsig short)va_arg(arg, unsig int); \
304 else \
305      res = (unsig int)va_arg(arg, unsig int)
306 
307 #endif
308 
309 /*
310  * zyxprintf - return length, as snprintf
311  */
312 
313 static int
314 xyzprintf (struct snprintf_state *state, const char *char_format, va_list ap)
315 {
316   const unsigned char *format = (const unsigned char *)char_format;
317   unsigned char c;
318   int len = 0;
319 
320   while((c = *format++)) {
321     if (c == '%') {
322       int flags          = 0;
323       int width          = 0;
324       int prec           = -1;
325       int long_long_flag = 0;
326       int long_flag      = 0;
327       int short_flag     = 0;
328 
329       /* flags */
330       while((c = *format++)){
331 	if(c == '-')
332 	  flags |= minus_flag;
333 	else if(c == '+')
334 	  flags |= plus_flag;
335 	else if(c == ' ')
336 	  flags |= space_flag;
337 	else if(c == '#')
338 	  flags |= alternate_flag;
339 	else if(c == '0')
340 	  flags |= zero_flag;
341 	else if(c == '\'')
342 	    ; /* just ignore */
343 	else
344 	  break;
345       }
346 
347       if((flags & space_flag) && (flags & plus_flag))
348 	flags ^= space_flag;
349 
350       if((flags & minus_flag) && (flags & zero_flag))
351 	flags ^= zero_flag;
352 
353       /* width */
354       if (isdigit(c))
355 	do {
356 	  width = width * 10 + c - '0';
357 	  c = *format++;
358 	} while(isdigit(c));
359       else if(c == '*') {
360 	width = va_arg(ap, int);
361 	c = *format++;
362       }
363 
364       /* precision */
365       if (c == '.') {
366 	prec = 0;
367 	c = *format++;
368 	if (isdigit(c))
369 	  do {
370 	    prec = prec * 10 + c - '0';
371 	    c = *format++;
372 	  } while(isdigit(c));
373 	else if (c == '*') {
374 	  prec = va_arg(ap, int);
375 	  c = *format++;
376 	}
377       }
378 
379       /* size */
380 
381       if (c == 'h') {
382 	short_flag = 1;
383 	c = *format++;
384       } else if (c == 'l') {
385 	long_flag = 1;
386 	c = *format++;
387 	if (c == 'l') {
388 	    long_long_flag = 1;
389 	    c = *format++;
390 	}
391       }
392 
393       switch (c) {
394       case 'c' :
395 	append_char(state, va_arg(ap, int), width, flags);
396 	++len;
397 	break;
398       case 's' :
399 	len += append_string(state,
400 			     va_arg(ap, unsigned char*),
401 			     width,
402 			     prec,
403 			     flags);
404 	break;
405       case 'd' :
406       case 'i' : {
407 	longest arg;
408 	u_longest num;
409 	int minusp = 0;
410 
411 	PARSE_INT_FORMAT(arg, ap, signed);
412 
413 	if (arg < 0) {
414 	  minusp = 1;
415 	  num = -arg;
416 	} else
417 	  num = arg;
418 
419 	len += append_number (state, num, 10, "0123456789",
420 			      width, prec, flags, minusp);
421 	break;
422       }
423       case 'u' : {
424 	u_longest arg;
425 
426 	PARSE_INT_FORMAT(arg, ap, unsigned);
427 
428 	len += append_number (state, arg, 10, "0123456789",
429 			      width, prec, flags, 0);
430 	break;
431       }
432       case 'o' : {
433 	u_longest arg;
434 
435 	PARSE_INT_FORMAT(arg, ap, unsigned);
436 
437 	len += append_number (state, arg, 010, "01234567",
438 			      width, prec, flags, 0);
439 	break;
440       }
441       case 'x' : {
442 	u_longest arg;
443 
444 	PARSE_INT_FORMAT(arg, ap, unsigned);
445 
446 	len += append_number (state, arg, 0x10, "0123456789abcdef",
447 			      width, prec, flags, 0);
448 	break;
449       }
450       case 'X' :{
451 	u_longest arg;
452 
453 	PARSE_INT_FORMAT(arg, ap, unsigned);
454 
455 	len += append_number (state, arg, 0x10, "0123456789ABCDEF",
456 			      width, prec, flags, 0);
457 	break;
458       }
459       case 'p' : {
460 	unsigned long arg = (unsigned long)va_arg(ap, void*);
461 
462 	len += append_number (state, arg, 0x10, "0123456789ABCDEF",
463 			      width, prec, flags, 0);
464 	break;
465       }
466       case 'n' : {
467 	int *arg = va_arg(ap, int*);
468 	*arg = state->s - state->str;
469 	break;
470       }
471       case '\0' :
472 	  --format;
473 	  /* FALLTHROUGH */
474       case '%' :
475 	(*state->append_char)(state, c);
476 	++len;
477 	break;
478       default :
479 	(*state->append_char)(state, '%');
480 	(*state->append_char)(state, c);
481 	len += 2;
482 	break;
483       }
484     } else {
485       (*state->append_char) (state, c);
486       ++len;
487     }
488   }
489   return len;
490 }
491 
492 #if !defined(HAVE_SNPRINTF) || defined(TEST_SNPRINTF)
493 int
494 snprintf (char *str, size_t sz, const char *format, ...)
495 {
496   va_list args;
497   int ret;
498 
499   va_start(args, format);
500   ret = vsnprintf (str, sz, format, args);
501   va_end(args);
502 
503 #ifdef PARANOIA
504   {
505     int ret2;
506     char *tmp;
507 
508     tmp = malloc (sz);
509     if (tmp == NULL)
510       abort ();
511 
512     va_start(args, format);
513     ret2 = vsprintf (tmp, format, args);
514     va_end(args);
515     if (ret != ret2 || strcmp(str, tmp))
516       abort ();
517     free (tmp);
518   }
519 #endif
520 
521   return ret;
522 }
523 #endif
524 
525 #if !defined(HAVE_ASPRINTF) || defined(TEST_SNPRINTF)
526 int
527 asprintf (char **ret, const char *format, ...)
528 {
529   va_list args;
530   int val;
531 
532   va_start(args, format);
533   val = vasprintf (ret, format, args);
534   va_end(args);
535 
536 #ifdef PARANOIA
537   {
538     int ret2;
539     char *tmp;
540     tmp = malloc (val + 1);
541     if (tmp == NULL)
542       abort ();
543 
544     va_start(args, format);
545     ret2 = vsprintf (tmp, format, args);
546     va_end(args);
547     if (val != ret2 || strcmp(*ret, tmp))
548       abort ();
549     free (tmp);
550   }
551 #endif
552 
553   return val;
554 }
555 #endif
556 
557 #if !defined(HAVE_ASNPRINTF) || defined(TEST_SNPRINTF)
558 int
559 asnprintf (char **ret, size_t max_sz, const char *format, ...)
560 {
561   va_list args;
562   int val;
563 
564   va_start(args, format);
565   val = vasnprintf (ret, max_sz, format, args);
566 
567 #ifdef PARANOIA
568   {
569     int ret2;
570     char *tmp;
571     tmp = malloc (val + 1);
572     if (tmp == NULL)
573       abort ();
574 
575     ret2 = vsprintf (tmp, format, args);
576     if (val != ret2 || strcmp(*ret, tmp))
577       abort ();
578     free (tmp);
579   }
580 #endif
581 
582   va_end(args);
583   return val;
584 }
585 #endif
586 
587 #if !defined(HAVE_VASPRINTF) || defined(TEST_SNPRINTF)
588 int
589 vasprintf (char **ret, const char *format, va_list args)
590 {
591   return vasnprintf (ret, 0, format, args);
592 }
593 #endif
594 
595 
596 #if !defined(HAVE_VASNPRINTF) || defined(TEST_SNPRINTF)
597 int
598 vasnprintf (char **ret, size_t max_sz, const char *format, va_list args)
599 {
600   int st;
601   struct snprintf_state state;
602 
603   state.max_sz = max_sz;
604   state.sz     = 1;
605   state.str    = malloc(state.sz);
606   if (state.str == NULL) {
607     *ret = NULL;
608     return -1;
609   }
610   state.s = state.str;
611   state.theend = state.s + state.sz - 1;
612   state.append_char = as_append_char;
613 
614   st = xyzprintf (&state, format, args);
615   if (st > state.sz) {
616     free (state.str);
617     *ret = NULL;
618     return -1;
619   } else {
620     char *tmp;
621 
622     *state.s = '\0';
623     tmp = realloc (state.str, st+1);
624     if (tmp == NULL) {
625       free (state.str);
626       *ret = NULL;
627       return -1;
628     }
629     *ret = tmp;
630     return st;
631   }
632 }
633 #endif
634 
635 #if !defined(HAVE_VSNPRINTF) || defined(TEST_SNPRINTF)
636 int
637 vsnprintf (char *str, size_t sz, const char *format, va_list args)
638 {
639   struct snprintf_state state;
640   int ret;
641   unsigned char *ustr = (unsigned char *)str;
642 
643   state.max_sz = 0;
644   state.sz     = sz;
645   state.str    = ustr;
646   state.s      = ustr;
647   state.theend = ustr + sz - (sz > 0);
648   state.append_char = sn_append_char;
649 
650   ret = xyzprintf (&state, format, args);
651   if (state.s != NULL)
652     *state.s = '\0';
653   return ret;
654 }
655 #endif
656