Go to most recent revision | Details | Last modification | View Log | RSS feed
Rev | Author | Line No. | Line |
---|---|---|---|
1901 | serge | 1 | /* |
2 | * Revision 12: http://theos.com/~deraadt/snprintf.c |
||
3 | * |
||
4 | * Copyright (c) 1997 Theo de Raadt |
||
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 | * 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. |
||
14 | * |
||
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. |
||
25 | */ |
||
26 | |||
27 | #ifndef __VMS |
||
28 | # include |
||
29 | #endif |
||
30 | #include |
||
31 | #include |
||
32 | #include |
||
33 | #include |
||
34 | #if __STDC__ |
||
35 | #include |
||
36 | #include |
||
37 | #else |
||
38 | #include |
||
39 | #endif |
||
40 | #include |
||
41 | #include |
||
42 | #include |
||
43 | |||
44 | #ifndef roundup |
||
45 | #define roundup(x, y) ((((x)+((y)-1))/(y))*(y)) |
||
46 | #endif |
||
47 | |||
48 | #ifdef __sgi |
||
49 | #define size_t ssize_t |
||
50 | #endif |
||
51 | |||
52 | static int pgsize; |
||
53 | static char *curobj; |
||
54 | static int caught; |
||
55 | static sigjmp_buf bail; |
||
56 | |||
57 | #define EXTRABYTES 2 /* XXX: why 2? you don't want to know */ |
||
58 | |||
59 | static char * |
||
60 | msetup(str, n) |
||
61 | char *str; |
||
62 | size_t n; |
||
63 | { |
||
64 | char *e; |
||
65 | |||
66 | if (n == 0) |
||
67 | return NULL; |
||
68 | if (pgsize == 0) |
||
69 | pgsize = getpagesize(); |
||
70 | curobj = (char *)malloc(n + EXTRABYTES + pgsize * 2); |
||
71 | if (curobj == NULL) |
||
72 | return NULL; |
||
73 | e = curobj + n + EXTRABYTES; |
||
74 | e = (char *)roundup((unsigned long)e, pgsize); |
||
75 | if (mprotect(e, pgsize, PROT_NONE) == -1) { |
||
76 | free(curobj); |
||
77 | curobj = NULL; |
||
78 | return NULL; |
||
79 | } |
||
80 | e = e - n - EXTRABYTES; |
||
81 | *e = '\0'; |
||
82 | return (e); |
||
83 | } |
||
84 | |||
85 | static void |
||
86 | mcatch( int a ) |
||
87 | { |
||
88 | siglongjmp(bail, 1); |
||
89 | } |
||
90 | |||
91 | static void |
||
92 | mcleanup(str, n, p) |
||
93 | char *str; |
||
94 | size_t n; |
||
95 | char *p; |
||
96 | { |
||
97 | strncpy(str, p, n-1); |
||
98 | str[n-1] = '\0'; |
||
99 | if (mprotect((caddr_t)(p + n + EXTRABYTES), pgsize, |
||
100 | PROT_READ|PROT_WRITE|PROT_EXEC) == -1) |
||
101 | mprotect((caddr_t)(p + n + EXTRABYTES), pgsize, |
||
102 | PROT_READ|PROT_WRITE); |
||
103 | free(curobj); |
||
104 | } |
||
105 | |||
106 | int |
||
107 | #if __STDC__ |
||
108 | vsnprintf(char *str, size_t n, char const *fmt, va_list ap) |
||
109 | #else |
||
110 | vsnprintf(str, n, fmt, ap) |
||
111 | char *str; |
||
112 | size_t n; |
||
113 | char *fmt; |
||
114 | char *ap; |
||
115 | #endif |
||
116 | { |
||
117 | struct sigaction osa, nsa; |
||
118 | char *p; |
||
119 | int ret = n + 1; /* if we bail, indicated we overflowed */ |
||
120 | |||
121 | memset(&nsa, 0, sizeof nsa); |
||
122 | nsa.sa_handler = mcatch; |
||
123 | sigemptyset(&nsa.sa_mask); |
||
124 | |||
125 | p = msetup(str, n); |
||
126 | if (p == NULL) { |
||
127 | *str = '\0'; |
||
128 | return 0; |
||
129 | } |
||
130 | if (sigsetjmp(bail, 1) == 0) { |
||
131 | if (sigaction(SIGSEGV, &nsa, &osa) == -1) { |
||
132 | mcleanup(str, n, p); |
||
133 | return (0); |
||
134 | } |
||
135 | ret = vsprintf(p, fmt, ap); |
||
136 | } |
||
137 | mcleanup(str, n, p); |
||
138 | (void) sigaction(SIGSEGV, &osa, NULL); |
||
139 | return (ret); |
||
140 | } |
||
141 | |||
142 | int |
||
143 | #if __STDC__ |
||
144 | snprintf(char *str, size_t n, char const *fmt, ...) |
||
145 | #else |
||
146 | snprintf(str, n, fmt, va_alist) |
||
147 | char *str; |
||
148 | size_t n; |
||
149 | char *fmt; |
||
150 | va_dcl |
||
151 | #endif |
||
152 | { |
||
153 | va_list ap; |
||
154 | #if __STDC__ |
||
155 | va_start(ap, fmt); |
||
156 | #else |
||
157 | va_start(ap); |
||
158 | #endif |
||
159 | |||
160 | return (vsnprintf(str, n, fmt, ap)); |
||
161 | va_end(ap); |
||
162 | } |
||
163 |