diff options
Diffstat (limited to 'src/lv2_evbuf.c')
| -rw-r--r-- | src/lv2_evbuf.c | 180 |
1 files changed, 180 insertions, 0 deletions
diff --git a/src/lv2_evbuf.c b/src/lv2_evbuf.c new file mode 100644 index 0000000..d7012c7 --- /dev/null +++ b/src/lv2_evbuf.c @@ -0,0 +1,180 @@ +/* + Copyright 2008-2018 David Robillard <http://drobilla.net> + + Permission to use, copy, modify, and/or distribute this software for any + purpose with or without fee is hereby granted, provided that the above + copyright notice and this permission notice appear in all copies. + + THIS SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. +*/ + +#include <assert.h> +#include <stdlib.h> +#include <string.h> + +#include "lv2/lv2plug.in/ns/ext/atom/atom.h" + +#include "lv2_evbuf.h" + +struct LV2_Evbuf_Impl { + uint32_t capacity; + uint32_t atom_Chunk; + uint32_t atom_Sequence; + LV2_Atom_Sequence buf; +}; + +static inline uint32_t +lv2_evbuf_pad_size(uint32_t size) +{ + return (size + 7) & (~7); +} + +LV2_Evbuf* +lv2_evbuf_new(uint32_t capacity, uint32_t atom_Chunk, uint32_t atom_Sequence) +{ + // FIXME: memory must be 64-bit aligned + LV2_Evbuf* evbuf = (LV2_Evbuf*)malloc( + sizeof(LV2_Evbuf) + sizeof(LV2_Atom_Sequence) + capacity); + evbuf->capacity = capacity; + evbuf->atom_Chunk = atom_Chunk; + evbuf->atom_Sequence = atom_Sequence; + lv2_evbuf_reset(evbuf, true); + return evbuf; +} + +void +lv2_evbuf_free(LV2_Evbuf* evbuf) +{ + free(evbuf); +} + +void +lv2_evbuf_reset(LV2_Evbuf* evbuf, bool input) +{ + if (input) { + evbuf->buf.atom.size = sizeof(LV2_Atom_Sequence_Body); + evbuf->buf.atom.type = evbuf->atom_Sequence; + } else { + evbuf->buf.atom.size = evbuf->capacity; + evbuf->buf.atom.type = evbuf->atom_Chunk; + } +} + +uint32_t +lv2_evbuf_get_size(LV2_Evbuf* evbuf) +{ + assert(evbuf->buf.atom.type != evbuf->atom_Sequence + || evbuf->buf.atom.size >= sizeof(LV2_Atom_Sequence_Body)); + return evbuf->buf.atom.type == evbuf->atom_Sequence + ? evbuf->buf.atom.size - sizeof(LV2_Atom_Sequence_Body) + : 0; +} + +void* +lv2_evbuf_get_buffer(LV2_Evbuf* evbuf) +{ + return &evbuf->buf; +} + +LV2_Evbuf_Iterator +lv2_evbuf_begin(LV2_Evbuf* evbuf) +{ + LV2_Evbuf_Iterator iter = { evbuf, 0 }; + return iter; +} + +LV2_Evbuf_Iterator +lv2_evbuf_end(LV2_Evbuf* evbuf) +{ + const uint32_t size = lv2_evbuf_get_size(evbuf); + const LV2_Evbuf_Iterator iter = { evbuf, lv2_evbuf_pad_size(size) }; + return iter; +} + +bool +lv2_evbuf_is_valid(LV2_Evbuf_Iterator iter) +{ + return iter.offset < lv2_evbuf_get_size(iter.evbuf); +} + +LV2_Evbuf_Iterator +lv2_evbuf_next(LV2_Evbuf_Iterator iter) +{ + if (!lv2_evbuf_is_valid(iter)) { + return iter; + } + + LV2_Evbuf* evbuf = iter.evbuf; + uint32_t offset = iter.offset; + uint32_t size; + size = ((LV2_Atom_Event*) + ((char*)LV2_ATOM_CONTENTS(LV2_Atom_Sequence, &evbuf->buf.atom) + + offset))->body.size; + offset += lv2_evbuf_pad_size(sizeof(LV2_Atom_Event) + size); + + LV2_Evbuf_Iterator next = { evbuf, offset }; + return next; +} + +bool +lv2_evbuf_get(LV2_Evbuf_Iterator iter, + uint32_t* frames, + uint32_t* subframes, + uint32_t* type, + uint32_t* size, + uint8_t** data) +{ + *frames = *subframes = *type = *size = 0; + *data = NULL; + + if (!lv2_evbuf_is_valid(iter)) { + return false; + } + + LV2_Atom_Sequence* aseq = &iter.evbuf->buf; + LV2_Atom_Event* aev = (LV2_Atom_Event*)( + (char*)LV2_ATOM_CONTENTS(LV2_Atom_Sequence, aseq) + iter.offset); + + *frames = aev->time.frames; + *subframes = 0; + *type = aev->body.type; + *size = aev->body.size; + *data = (uint8_t*)LV2_ATOM_BODY(&aev->body); + + return true; +} + +bool +lv2_evbuf_write(LV2_Evbuf_Iterator* iter, + uint32_t frames, + uint32_t subframes, + uint32_t type, + uint32_t size, + const uint8_t* data) +{ + LV2_Atom_Sequence* aseq = &iter->evbuf->buf; + if (iter->evbuf->capacity - sizeof(LV2_Atom) - aseq->atom.size < + sizeof(LV2_Atom_Event) + size) { + return false; + } + + LV2_Atom_Event* aev = (LV2_Atom_Event*)( + (char*)LV2_ATOM_CONTENTS(LV2_Atom_Sequence, aseq) + iter->offset); + + aev->time.frames = frames; + aev->body.type = type; + aev->body.size = size; + memcpy(LV2_ATOM_BODY(&aev->body), data, size); + + size = lv2_evbuf_pad_size(sizeof(LV2_Atom_Event) + size); + aseq->atom.size += size; + iter->offset += size; + + return true; +} |