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Diffstat (limited to 'ns/ext/reference/reference.h')
| -rw-r--r-- | ns/ext/reference/reference.h | 161 |
1 files changed, 161 insertions, 0 deletions
diff --git a/ns/ext/reference/reference.h b/ns/ext/reference/reference.h new file mode 100644 index 0000000..26ef4c3 --- /dev/null +++ b/ns/ext/reference/reference.h @@ -0,0 +1,161 @@ +/* + Copyright 2008-2011 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. +*/ + +/** + @file reference.h C header for the LV2 Reference extension + <http://lv2plug.in/ns/ext/reference>. +*/ + +#ifndef LV2_REFERENCE_H +#define LV2_REFERENCE_H + +#define LV2_REFERENCE_URI "http://lv2plug.in/ns/ext/reference" +#define LV2_REFERENCE_BLOB_SUPPORT_URI LV2_REFERENCE_URI "#blobSupport" + +#include <stdint.h> +#include <stddef.h> + +#include "lv2/lv2plug.in/ns/ext/atom/atom.h" + +/** + Dynamically Allocated Data. + + This is an opaque piece of data of any type, dynamically allocated in memory. + Unlike an "atom", a "blob" is not necessarily POD. Non-POD data is referred + to by a "reference (a special case of atom with type 0). + + This is a pointer to host data which is opaque to the plugin. Plugins MUST + NOT interpret this data in any way, except via host-provided functions in + LV2_Blob_Support. +*/ +typedef void* LV2_Blob; + +typedef LV2_Atom LV2_Reference; + +typedef void* LV2_Blob_Support_Data; + +typedef void (*LV2_Blob_Destroy)(LV2_Blob* blob); + +/** + The data field of the LV2_Feature for reference:blobSupport. + + A host which supports blobs must pass an LV2_Feature to the plugin's + instantiate method with 'URI' = "http://lv2plug.in/ns/ext/reference#blobSupport" + and 'data' pointing to an instance of this struct. All fields of this struct + MUST be set to non-NULL values by the host, except possibly 'data'. +*/ +typedef struct { + + /** + Pointer to opaque host data. + + The plugin MUST pass this to any call to functions in this struct. + Otherwise, the plugin MUST NOT interpret this value in any way. + */ + LV2_Blob_Support_Data data; + + /** + The size of a reference, in bytes. + + This value is provided by the host so plugins can allocate large enough + chunks of memory to store references. Note a reference is an LV2_Reference + with type reference:Reference, hence ref_size is a uint16, like + LV2_Reference.size. + */ + uint16_t ref_size; + + /** + Return the Blob referred to by @a ref. + + The returned value MUST NOT be used in any way other than by calling + methods defined in LV2_Blob_Support (e.g. it MUST NOT be directly + accessed, copied, or destroyed). The actual payload of the blob can + be accessed with LV2_Blob_Support.blob_get. + */ + LV2_Blob (*ref_get)(LV2_Blob_Support_Data data, + LV2_Reference* ref); + + /** + Copy a reference. + This copies a reference but not the blob it refers to, + i.e. after this call @a dst and @a src refer to the same LV2_Blob. + */ + void (*ref_copy)(LV2_Blob_Support_Data data, + LV2_Reference* dst, + LV2_Reference* src); + + /** + Reset (release) a reference. + After this call, @a ref is invalid. Implementations must be sure to + call this function when necessary, or memory leaks will result. The + specific times this is necessary MUST be defined by any extensions that + define a mechanism for transporting references. The standard semantics are: + <ul><li>Whenever passed a Reference (e.g. via a Port) and run, the + plugin owns that reference.</li> + <li>The plugin owns any reference it creates (e.g. by using blob_new or + ref_copy).</li> + <li>For any reference it owns, the plugin MUST either: + <ul><li>Copy the reference and store it (to be used in future runs and + released later).</li> + <li>Copy the reference to an output port exactly once.</li> + <li>Release it with ref_reset.</li></ul></li> + </ul> + */ + void (*ref_reset)(LV2_Blob_Support_Data data, + LV2_Reference* ref); + + /** + Initialize a reference to point to a newly allocated Blob. + + @param data Must be the data member of this struct. + @param ref Pointer to an area of memory at least as large as + the ref_size field of this struct. On return, this will + be the unique reference to the new blob, which is owned by the + caller. Assumed to be uninitialised, i.e. the caller MUST NOT + pass a valid reference since this could cause a memory leak. + @param destroy Function to destroy this blob. This function + MUST clean up any resources contained in the blob, but MUST NOT + attempt to free the memory pointed to by its LV2_Blob* parameter + (since this is allocated by the host). + @param type ID of type of blob to allocate. + @param size Size of blob to allocate in bytes. + */ + void (*blob_new)(LV2_Blob_Support_Data data, + LV2_Reference* ref, + LV2_Blob_Destroy destroy, + uint32_t type, + size_t size); + + /** + Get blob's type as an ID. + + The return value may be any type URI, mapped to an integer with the + URI Map extension with <code>context = NULL</code>. + */ + uint32_t (*blob_type)(LV2_Blob blob); + + /** + Get blob's body. + + Returns a pointer to the start of the blob data. The format of this + data is defined by the return value of the type method. It MUST NOT + be used in any way by code which does not understand that type. + */ + void* (*blob_data)(LV2_Blob blob); + +} LV2_Blob_Support; + +#endif /* LV2_REFERENCE_H */ |