From 12c86dfba742f1ac3585846f52d5039e9854861c Mon Sep 17 00:00:00 2001 From: David Robillard Date: Sat, 18 Feb 2012 20:53:15 +0000 Subject: Implement writing to forge sink. --- lv2/lv2plug.in/ns/ext/atom/forge.h | 72 ++++++++++++++++++++++++-------------- 1 file changed, 46 insertions(+), 26 deletions(-) (limited to 'lv2') diff --git a/lv2/lv2plug.in/ns/ext/atom/forge.h b/lv2/lv2plug.in/ns/ext/atom/forge.h index 19b76e7..4db9638 100644 --- a/lv2/lv2plug.in/ns/ext/atom/forge.h +++ b/lv2/lv2plug.in/ns/ext/atom/forge.h @@ -53,11 +53,13 @@ extern "C" { # include #endif +/** Handle for LV2_Atom_Forge_Sink. */ typedef void* LV2_Atom_Forge_Sink_Handle; -typedef uint32_t (*LV2_Atom_Forge_Sink)(LV2_Atom_Forge_Sink_Handle handle, - const void* buf, - uint32_t size); +/** Sink function for writing output. See lv2_atom_forge_set_sink(). */ +typedef void* (*LV2_Atom_Forge_Sink)(LV2_Atom_Forge_Sink_Handle handle, + const void* buf, + uint32_t size); /** A stack frame used for keeping track of nested Atom containers. */ typedef struct _LV2_Atom_Forge_Frame { @@ -125,9 +127,22 @@ lv2_atom_forge_set_buffer(LV2_Atom_Forge* forge, uint8_t* buf, size_t size) forge->buf = buf; forge->size = size; forge->offset = 0; + forge->sink = NULL; + forge->handle = NULL; } -/** Set the sink function where @p forge will write output. */ +/** + Set the sink function where @p forge will write output. + + The return value of forge functions is a pointer to the written data, which + is used for updating parent sizes. To enable this, the sink function must + return a valid pointer to a contiguous LV2_Atom header. For ringbuffers, + this should be possible as long as the size of the buffer is a multiple of + sizeof(LV2_Atom), since atoms are always aligned. When using a ringbuffer, + the returned pointers may not point to a complete atom (including body). + The user must take care to only use these return values in a way compatible + with the sink used. +*/ static inline void lv2_atom_forge_set_sink(LV2_Atom_Forge* forge, LV2_Atom_Forge_Sink sink, @@ -172,15 +187,21 @@ lv2_atom_forge_write_nopad(LV2_Atom_Forge* forge, const void* data, uint32_t size) { - /* TODO: Write to sink, if set */ - uint8_t* const out = forge->buf + forge->offset; - if (forge->offset + size > forge->size) { - return NULL; + uint8_t* out = NULL; + if (forge->sink) { + out = forge->sink(forge->handle, data, size); + } else { + out = forge->buf + forge->offset; + if (forge->offset + size > forge->size) { + return NULL; + } + forge->offset += size; + memcpy(out, data, size); } - forge->offset += size; - memcpy(out, data, size); - for (LV2_Atom_Forge_Frame* f = forge->stack; f; f = f->parent) { - f->atom->size += size; + if (out) { + for (LV2_Atom_Forge_Frame* f = forge->stack; f; f = f->parent) { + f->atom->size += size; + } } return out; } @@ -351,8 +372,7 @@ lv2_atom_forge_vector_head(LV2_Atom_Forge* forge, elem_count, elem_type }; - return (LV2_Atom_Vector*)lv2_atom_forge_write( - forge, &a, sizeof(a)); + return (LV2_Atom_Vector*)lv2_atom_forge_write(forge, &a, sizeof(a)); } /** Write a complete atom:Vector. */ @@ -388,12 +408,12 @@ lv2_atom_forge_vector(LV2_Atom_Forge* forge, lv2_atom_forge_pop(forge, &frame); @endcode */ -static inline LV2_Atom* +static inline LV2_Atom_Tuple* lv2_atom_forge_tuple(LV2_Atom_Forge* forge, LV2_Atom_Forge_Frame* frame) { const LV2_Atom_Tuple a = { { forge->Tuple, 0 } }; LV2_Atom* atom = lv2_atom_forge_write(forge, &a, sizeof(a)); - return lv2_atom_forge_push(forge, frame, atom); + return (LV2_Atom_Tuple*)lv2_atom_forge_push(forge, frame, atom); } /** @@ -420,7 +440,7 @@ lv2_atom_forge_tuple(LV2_Atom_Forge* forge, LV2_Atom_Forge_Frame* frame) lv2_atom_forge_pop(forge, &frame); @endcode */ -static inline LV2_Atom* +static inline LV2_Atom_Object* lv2_atom_forge_resource(LV2_Atom_Forge* forge, LV2_Atom_Forge_Frame* frame, LV2_URID id, @@ -432,13 +452,13 @@ lv2_atom_forge_resource(LV2_Atom_Forge* forge, otype }; LV2_Atom* atom = (LV2_Atom*)lv2_atom_forge_write(forge, &a, sizeof(a)); - return lv2_atom_forge_push(forge, frame, atom); + return (LV2_Atom_Object*)lv2_atom_forge_push(forge, frame, atom); } /** The same as lv2_atom_forge_resource(), but for object:Blank. */ -static inline LV2_Atom* +static inline LV2_Atom_Object* lv2_atom_forge_blank(LV2_Atom_Forge* forge, LV2_Atom_Forge_Frame* frame, uint32_t id, @@ -450,7 +470,7 @@ lv2_atom_forge_blank(LV2_Atom_Forge* forge, otype }; LV2_Atom* atom = (LV2_Atom*)lv2_atom_forge_write(forge, &a, sizeof(a)); - return lv2_atom_forge_push(forge, frame, atom); + return (LV2_Atom_Object*)lv2_atom_forge_push(forge, frame, atom); } /** @@ -472,7 +492,7 @@ lv2_atom_forge_property_head(LV2_Atom_Forge* forge, The size of the returned sequence will be 0, so passing it as the parent parameter to other forge methods will do the right thing. */ -static inline LV2_Atom* +static inline LV2_Atom_Sequence* lv2_atom_forge_sequence_head(LV2_Atom_Forge* forge, LV2_Atom_Forge_Frame* frame, uint32_t unit) @@ -483,7 +503,7 @@ lv2_atom_forge_sequence_head(LV2_Atom_Forge* forge, 0 }; LV2_Atom* atom = (LV2_Atom*)lv2_atom_forge_write(forge, &a, sizeof(a)); - return lv2_atom_forge_push(forge, frame, atom); + return (LV2_Atom_Sequence*)lv2_atom_forge_push(forge, frame, atom); } /** @@ -491,13 +511,13 @@ lv2_atom_forge_sequence_head(LV2_Atom_Forge* forge, After this, call the appropriate forge method(s) to write the body, passing the same @p parent parameter. Note the returned LV2_Event is NOT an Atom. */ -static inline LV2_Atom_Event* +static inline LV2_Atom_Audio_Time* lv2_atom_forge_audio_time(LV2_Atom_Forge* forge, uint32_t frames, uint32_t subframes) { const LV2_Atom_Audio_Time a = { frames, subframes }; - return (LV2_Atom_Event*)lv2_atom_forge_write(forge, &a, sizeof(a)); + return (LV2_Atom_Audio_Time*)lv2_atom_forge_write(forge, &a, sizeof(a)); } /** @@ -505,11 +525,11 @@ lv2_atom_forge_audio_time(LV2_Atom_Forge* forge, After this, call the appropriate forge method(s) to write the body, passing the same @p parent parameter. Note the returned LV2_Event is NOT an Atom. */ -static inline LV2_Atom_Event* +static inline double* lv2_atom_forge_beat_time(LV2_Atom_Forge* forge, double beats) { - return (LV2_Atom_Event*)lv2_atom_forge_write(forge, &beats, sizeof(beats)); + return (double*)lv2_atom_forge_write(forge, &beats, sizeof(beats)); } #ifdef __cplusplus -- cgit v1.2.1