[sync] sync code from internal

components/libc/vsprintf.c

@@ -0,0 +1,20 @@
+#include <stdint.h>
+#include <stdarg.h>
+#include <stddef.h>
+#include <stdio.h>
+
+/**
+ * This function will fill a formatted string to buffer.
+ *
+ * @param  buf is the buffer to save formatted string.
+ *
+ * @param  format is the format parameters.
+ *
+ * @param  arg_ptr is a list of variable parameters.
+ *
+ * @return The number of characters actually written to buffer.
+ */
+int vsprintf(char *buf, const char *format, va_list arg_ptr)
+{
+    return vsnprintf(buf, (size_t) - 1, format, arg_ptr);
+}