minimal plan9port to cross-build Jehanne

lib/lib9/fmt/sprint.c

@@ -0,0 +1,30 @@
+/* Copyright (c) 2002-2006 Lucent Technologies; see LICENSE */
+#include <stdarg.h>
+#include <fmt.h>
+#include "plan9.h"
+#include "fmt.h"
+#include "fmtdef.h"
+
+int
+sprint(char *buf, char *fmt, ...)
+{
+	int n;
+	uint len;
+	va_list args;
+
+	len = 1<<30;  /* big number, but sprint is deprecated anyway */
+	/*
+	 * on PowerPC, the stack is near the top of memory, so
+	 * we must be sure not to overflow a 32-bit pointer.
+	 *
+	 * careful!  gcc-4.2 assumes buf+len < buf can never be true and
+	 * optimizes the test away.  casting to uintptr works around this bug.
+	 */
+	if((uintptr)buf+len < (uintptr)buf)
+		len = -(uintptr)buf-1;
+
+	va_start(args, fmt);
+	n = vsnprint(buf, len, fmt, args);
+	va_end(args);
+	return n;
+}