1 files changed, 149 insertions, 0 deletions
diff --git a/src/clib/snprintf.c b/src/clib/snprintf.c
new file mode 100644
index 00000000..6b31d850
--- /dev/null
+++ b/src/clib/snprintf.c
@@ -0,0 +1,149 @@
+/*-
+ * See the file LICENSE for redistribution information.
+ *
+ * Copyright (c) 1996, 2012 Oracle and/or its affiliates.  All rights reserved.
+ *
+ * $Id$
+ */
+
+#include "db_config.h"
+
+#include "db_int.h"
+
+#if !defined(HAVE_SNPRINTF) || !defined(HAVE_VSNPRINTF)
+static void sprintf_overflow __P((void));
+static int  sprintf_retcharpnt __P((void));
+#endif
+
+/*
+ * snprintf --
+ *	Bounded version of sprintf.
+ *
+ * PUBLIC: #ifndef HAVE_SNPRINTF
+ * PUBLIC: int snprintf __P((char *, size_t, const char *, ...));
+ * PUBLIC: #endif
+ */
+#ifndef HAVE_SNPRINTF
+int
+#ifdef STDC_HEADERS
+snprintf(char *str, size_t n, const char *fmt, ...)
+#else
+snprintf(str, n, fmt, va_alist)
+	char *str;
+	size_t n;
+	const char *fmt;
+	va_dcl
+#endif
+{
+	static int ret_charpnt = -1;
+	va_list ap;
+	size_t len;
+
+	if (ret_charpnt == -1)
+		ret_charpnt = sprintf_retcharpnt();
+
+#ifdef STDC_HEADERS
+	va_start(ap, fmt);
+#else
+	va_start(ap);
+#endif
+	len = (size_t)vsprintf(str, fmt, ap);
+	if (ret_charpnt)
+		len = strlen(str);
+
+	va_end(ap);
+
+	if (len >= n) {
+		sprintf_overflow();
+		/* NOTREACHED */
+	}
+	return ((int)len);
+}
+#endif
+
+/*
+ * vsnprintf --
+ *	Bounded version of vsprintf.
+ *
+ * PUBLIC: #ifndef HAVE_VSNPRINTF
+ * PUBLIC: int vsnprintf __P((char *, size_t, const char *, va_list));
+ * PUBLIC: #endif
+ */
+#ifndef HAVE_VSNPRINTF
+int
+vsnprintf(str, n, fmt, ap)
+	char *str;
+	size_t n;
+	const char *fmt;
+	va_list ap;
+{
+	static int ret_charpnt = -1;
+	size_t len;
+
+	if (ret_charpnt == -1)
+		ret_charpnt = sprintf_retcharpnt();
+
+	len = (size_t)vsprintf(str, fmt, ap);
+	if (ret_charpnt)
+		len = strlen(str);
+
+	if (len >= n) {
+		sprintf_overflow();
+		/* NOTREACHED */
+	}
+	return ((int)len);
+}
+#endif
+
+#if !defined(HAVE_SNPRINTF) || !defined(HAVE_VSNPRINTF)
+static void
+sprintf_overflow()
+{
+	/*
+	 * !!!
+	 * We're potentially manipulating strings handed us by the application,
+	 * and on systems without a real snprintf() the sprintf() calls could
+	 * have overflowed the buffer.  We can't do anything about it now, but
+	 * we don't want to return control to the application, we might have
+	 * overwritten the stack with a Trojan horse.  We're not trying to do
+	 * anything recoverable here because systems without snprintf support
+	 * are pretty rare anymore.
+	 */
+#define	OVERFLOW_ERROR	"internal buffer overflow, process ended\n"
+#ifndef	STDERR_FILENO
+#define	STDERR_FILENO	2
+#endif
+	(void)write(STDERR_FILENO, OVERFLOW_ERROR, sizeof(OVERFLOW_ERROR) - 1);
+
+	/* Be polite. */
+	exit(1);
+
+	/* But firm. */
+	__os_abort(NULL);
+
+	/* NOTREACHED */
+}
+
+static int
+sprintf_retcharpnt()
+{
+	int ret_charpnt;
+	char buf[10];
+
+	/*
+	 * Some old versions of sprintf return a pointer to the first argument
+	 * instead of a character count.  Assume the return value of snprintf,
+	 * vsprintf, etc. will be the same as sprintf, and check the easy one.
+	 *
+	 * We do this test at run-time because it's not a test we can do in a
+	 * cross-compilation environment.
+	 */
+
+	ret_charpnt =
+	    (int)sprintf(buf, "123") != 3 ||
+	    (int)sprintf(buf, "123456789") != 9 ||
+	    (int)sprintf(buf, "1234") != 4;
+
+	return (ret_charpnt);
+}
+#endif