diff options
Diffstat (limited to 'src/upb_sink.h')
| -rw-r--r-- | src/upb_sink.h | 22 |
1 files changed, 18 insertions, 4 deletions
diff --git a/src/upb_sink.h b/src/upb_sink.h index f117107..41e5275 100644 --- a/src/upb_sink.h +++ b/src/upb_sink.h @@ -98,9 +98,15 @@ typedef struct upb_sink_callbacks { upb_end_cb end_cb; } upb_sink_callbacks; -// We could potentially define these later to also be capable of calling a C++ -// virtual method instead of doing the virtual dispatch manually. This would -// make it possible to write C++ sinks in a more natural style without loss of +// These macros implement a mini virtual function dispatch for upb_sink instances. +// This allows functions that call upb_sinks to just write: +// +// upb_sink_onvalue(sink, field, val); +// +// The macro will handle the virtual function lookup and dispatch. We could +// potentially define these later to also be capable of calling a C++ virtual +// method instead of doing the virtual dispatch manually. This would make it +// possible to write C++ sinks in a more natural style without loss of // efficiency. We could have a flag in upb_sink defining whether it is a C // sink or a C++ one. #define upb_sink_onvalue(s, f, val) s->vtbl->value_cb(s, f, val) @@ -123,10 +129,18 @@ INLINE void upb_sink_init(upb_sink *s, upb_sink_callbacks *vtbl) { // // The two simplest kinds of sinks are "write to string" and "write to FILE*". +// A forward declaration solely for the benefit of declaring upb_byte_cb below. +// Always prefer upb_bytesink (without the "struct" keyword) instead. +struct _upb_bytesink; + // The single bytesink callback; it takes the bytes to be written and returns // how many were successfully written. If zero is returned, it indicates that // no more bytes can be accepted right now. -//typedef size_t (*upb_byte_cb)(upb_bytesink *s, upb_strptr str); +typedef size_t (*upb_byte_cb)(struct _upb_bytesink *s, upb_strptr str); + +typedef struct _upb_bytesink { + upb_byte_cb *cb; +} upb_bytesink; #ifdef __cplusplus } /* extern "C" */ |