--- /dev/null
+/*
+ * Revision 12: http://theos.com/~deraadt/snprintf.c
+ *
+ * Copyright (c) 1997 Theo de Raadt
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <sys/param.h>
+#include <sys/types.h>
+#include <sys/mman.h>
+#include <signal.h>
+#include <stdio.h>
+#if __STDC__
+#include <stdarg.h>
+#include <stdlib.h>
+#else
+#include <varargs.h>
+#endif
+#include <setjmp.h>
+#include <unistd.h>
+#include <string.h>
+
+#ifndef roundup
+#define roundup(x, y) ((((x)+((y)-1))/(y))*(y))
+#endif
+
+#ifdef __sgi
+#define size_t ssize_t
+#endif
+
+static int pgsize;
+static char *curobj;
+static int caught;
+static sigjmp_buf bail;
+
+#define EXTRABYTES 2 /* XXX: why 2? you don't want to know */
+
+static char *
+msetup(str, n)
+ char *str;
+ size_t n;
+{
+ char *e;
+
+ if (n == 0)
+ return NULL;
+ if (pgsize == 0)
+ pgsize = getpagesize();
+ curobj = (char *)malloc(n + EXTRABYTES + pgsize * 2);
+ if (curobj == NULL)
+ return NULL;
+ e = curobj + n + EXTRABYTES;
+ e = (char *)roundup((unsigned long)e, pgsize);
+ if (mprotect(e, pgsize, PROT_NONE) == -1) {
+ free(curobj);
+ curobj = NULL;
+ return NULL;
+ }
+ e = e - n - EXTRABYTES;
+ *e = '\0';
+ return (e);
+}
+
+static void
+ mcatch( int a )
+{
+ siglongjmp(bail, 1);
+}
+
+static void
+mcleanup(str, n, p)
+ char *str;
+ size_t n;
+ char *p;
+{
+ strncpy(str, p, n-1);
+ str[n-1] = '\0';
+ if (mprotect((caddr_t)(p + n + EXTRABYTES), pgsize,
+ PROT_READ|PROT_WRITE|PROT_EXEC) == -1)
+ mprotect((caddr_t)(p + n + EXTRABYTES), pgsize,
+ PROT_READ|PROT_WRITE);
+ free(curobj);
+}
+
+int
+#if __STDC__
+vsnprintf(char *str, size_t n, char const *fmt, va_list ap)
+#else
+vsnprintf(str, n, fmt, ap)
+ char *str;
+ size_t n;
+ char *fmt;
+ char *ap;
+#endif
+{
+ struct sigaction osa, nsa;
+ char *p;
+ int ret = n + 1; /* if we bail, indicated we overflowed */
+
+ memset(&nsa, 0, sizeof nsa);
+ nsa.sa_handler = mcatch;
+ sigemptyset(&nsa.sa_mask);
+
+ p = msetup(str, n);
+ if (p == NULL) {
+ *str = '\0';
+ return 0;
+ }
+ if (sigsetjmp(bail, 1) == 0) {
+ if (sigaction(SIGSEGV, &nsa, &osa) == -1) {
+ mcleanup(str, n, p);
+ return (0);
+ }
+ ret = vsprintf(p, fmt, ap);
+ }
+ mcleanup(str, n, p);
+ (void) sigaction(SIGSEGV, &osa, NULL);
+ return (ret);
+}
+
+int
+#if __STDC__
+snprintf(char *str, size_t n, char const *fmt, ...)
+#else
+snprintf(str, n, fmt, va_alist)
+ char *str;
+ size_t n;
+ char *fmt;
+ va_dcl
+#endif
+{
+ va_list ap;
+#if __STDC__
+ va_start(ap, fmt);
+#else
+ va_start(ap);
+#endif
+
+ return (vsnprintf(str, n, fmt, ap));
+ va_end(ap);
+}
+
+
+