2 * Revision 12: http://theos.com/~deraadt/snprintf.c
4 * Copyright (c) 1997 Theo de Raadt
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 #include <sys/param.h>
28 #include <sys/types.h>
43 #define roundup(x, y) ((((x)+((y)-1))/(y))*(y))
47 #define size_t ssize_t
53 static sigjmp_buf bail
;
55 #define EXTRABYTES 2 /* XXX: why 2? you don't want to know */
67 pgsize
= getpagesize();
68 curobj
= (char *)malloc(n
+ EXTRABYTES
+ pgsize
* 2);
71 e
= curobj
+ n
+ EXTRABYTES
;
72 e
= (char *)roundup((unsigned long)e
, pgsize
);
73 if (mprotect(e
, pgsize
, PROT_NONE
) == -1) {
78 e
= e
- n
- EXTRABYTES
;
97 if (mprotect((caddr_t
)(p
+ n
+ EXTRABYTES
), pgsize
,
98 PROT_READ
|PROT_WRITE
|PROT_EXEC
) == -1)
99 mprotect((caddr_t
)(p
+ n
+ EXTRABYTES
), pgsize
,
100 PROT_READ
|PROT_WRITE
);
106 vsnprintf(char *str
, size_t n
, char const *fmt
, va_list ap
)
108 vsnprintf(str
, n
, fmt
, ap
)
115 struct sigaction osa
, nsa
;
117 int ret
= n
+ 1; /* if we bail, indicated we overflowed */
119 memset(&nsa
, 0, sizeof nsa
);
120 nsa
.sa_handler
= mcatch
;
121 sigemptyset(&nsa
.sa_mask
);
128 if (sigsetjmp(bail
, 1) == 0) {
129 if (sigaction(SIGSEGV
, &nsa
, &osa
) == -1) {
133 ret
= vsprintf(p
, fmt
, ap
);
136 (void) sigaction(SIGSEGV
, &osa
, NULL
);
142 snprintf(char *str
, size_t n
, char const *fmt
, ...)
144 snprintf(str
, n
, fmt
, va_alist
)
158 return (vsnprintf(str
, n
, fmt
, ap
));