Reference VST3 modules for hosted-VST3 tests

Admission and refusal¶

The Event Probe admits, per block, at most 2048 input events and at most 4096 - events Marker points. Event payloads share 65536 + 4096 + 16 bytes of module storage: data bytes and UTF-16 text plus a terminator, each 2-aligned. Events on buses other than 0, and unknown or output-only event kinds, are ignored before their offset is examined. Parameter queues other than Marker are ignored unread.

Anything else malformed refuses the whole block. That covers:

• event or point counts that are negative or over capacity;
• offsets outside 0..frames-1, or nonzero in a zero-frame block;
• a null payload with a nonzero size, or payload overflow;
• a failed getEvent or getPoint, or a null queue;
• null bus or channel arrays, a wrong channel count, frames outside 0..maxSamplesPerBlock, or a mismatched sample size.

A refused block returns kResultFalse, zeroes every reachable output channel, posts no events or parameter points, and leaves the digest unchanged.

One exception is deliberate: the digest advances in the render, before output events and the Digest point are posted. If the host's output lists refuse addEvent or addPoint, the block returns kResultFalse with the digest already advanced, and the events posted so far stay in place.

The Keyed Sidechain refuses the same malformed-buffer cases, a missing key bus when the auxiliary bus is active, and a key channel count that differs from the arrangement. It also refuses setActive(true) before initialize.