1 // Copyright 2016 The Fuchsia Authors
2 // Copyright (c) 2008 Travis Geiselbrecht
3 //
4 // Use of this source code is governed by a MIT-style
5 // license that can be found in the LICENSE file or at
6 // https://opensource.org/licenses/MIT
7 
8 #pragma once
9 
10 #include <stdarg.h>
11 #include <zircon/compiler.h>
12 #include <stddef.h>
13 
14 __BEGIN_CDECLS
15 
16 /* printf engine that parses the format string and generates output */
17 
18 /* function pointer to pass the printf engine, called back during the formatting.
19  * input is a string to output, length bytes to output,
20  * return code is number of characters that would have been written, or error code (if negative)
21  */
22 typedef int (*_printf_engine_output_func)(const char *str, size_t len, void *state);
23 
24 #ifndef PRINTF_DECL
25 #define PRINTF_DECL(name) int name
26 #endif
27 #ifndef PRINTF_CALL
28 #define PRINTF_CALL(name) name
29 #endif
30 
31 PRINTF_DECL(_printf_engine)(_printf_engine_output_func out, void *state, const char *fmt, va_list ap);
32 
33 __END_CDECLS
34