Clarify resize-port extension.

2 files changed, 16 insertions, 12 deletions

diff --git a/ext/resize-port.lv2/resize-port.h b/ext/resize-port.lv2/resize-port.h
index 4ba533b..ad6a5dc 100644
--- a/ext/resize-port.lv2/resize-port.h
+++ b/ext/resize-port.lv2/resize-port.h
@@ -35,6 +35,16 @@ typedef struct {
 	 * This function MAY return false, in which case the port buffer was
 	 * not resized and the port is still connected to the same location.
 	 * Plugins MUST gracefully handle this situation.
+	 *
+	 * This function MUST NOT be called from any context other than
+	 * the context associated with the port of the given index.
+	 *
+	 * The host MUST preserve the contents of the port buffer when
+	 * resizing.
+	 *
+	 * Plugins MAY resize a port many times in a single run callback.
+	 * Hosts SHOULD make this an inexpensive as possible (i.e. plugins
+	 * can liberally use this function in a similar way to realloc).
 	 */
 	bool (*resize_port)(LV2_Resize_Port_Feature_Data data,
 	                    uint32_t                     index,
diff --git a/ext/resize-port.lv2/resize-port.ttl b/ext/resize-port.lv2/resize-port.ttl
index d6bbb35..7709c0a 100644
--- a/ext/resize-port.lv2/resize-port.ttl
+++ b/ext/resize-port.lv2/resize-port.ttl
@@ -40,19 +40,13 @@ An extension that allows LV2 plugins to request a resize of an output port.
 
 Any host which supports this extension must pass an LV2_Feature to
 the plugin's instantiate method with URI http://lv2plug.in/ns/ext/resize-port
-and a pointer to a
-<pre>
-struct {
-	void* host_handle;
-	void (*resize_port)(void* host_handle, uint32_t index);
-}
-</pre>
-where the plugin may call resize_port with the given host_handle from any
-context to demand the resize of an output port buffer.  The plugin MUST call
-this function from the context of the given port.
+and a pointer to a LV2_Resize_Port_Feature structure (see
+<a href="resize-port.h">resize-port.h</a> for details).  This structure
+provides a resize_port function which plugins may use to resize output
+port buffers as necessary.
 
-This function MAY return NULL at any time, plugins MUST gracefully handle
-this situation.
+This extension also defines several predicates useful for describing the
+amount of space required for a particular port buffer.
 """ .
 
 rsz:asLargeAs a rdf:Property ;