Struct PrismPluginBackend 

#[repr(C)]
pub struct PrismPluginBackend {
    pub abi_version: u64,
    pub struct_size: u32,
    pub reserved: u32,
    pub name: *const c_char,
    pub priority: c_int,
    pub features: u64,
    pub vtable: *const PrismBackendVTable,
    pub userdata: *mut c_void,
    pub plugin_version: u64,
}

A descriptor supplied by a plugin to describe a single backend.

Fields

abi_version: u64

The plugin ABI generation this descriptor was built against. A plugin MUST set this member to the PRISM_PLUGIN_ABI_VERSION against which it was compiled. Prism rejects a descriptor whose generation it does not accept, as described under ABI compatibility.

struct_size: u32

The size of this structure as the plugin understands it. A plugin MUST set this member to sizeof(PrismPluginBackend). Prism consults at most this many bytes.

reserved: u32

Reserved for future use. A plugin MUST set this member to zero.

name: *const c_char

The backend’s name, as a null-terminated UTF-8 string, subject to the same requirements and consequences as the name parameter of prism_registry_builder_add_backend. The backend’s identifier is derived from it by the hash function described in the chapter on backend identifiers. The string is copied during loading.

priority: c_int

The backend’s priority. Higher values indicate higher priority. This value MUST be non-negative unless the loading call supplies a priority override, in which case it is ignored.

features: u64

The feature set the backend declares, formed by ORing PRISM_BACKEND_* feature constants together. It MUST be consistent with the vtable in the sense required of any custom backend.

vtable: *const PrismBackendVTable

The vtable implementing the backend, subject to every requirement placed on a vtable by the chapter on custom backends. This member MUST NOT be NULL, and its size member MUST be set as that chapter requires. The vtable MUST provide a create member, as described under Host services. The vtable is copied during loading; the code it names remains valid while the library remains loaded.

userdata: *mut c_void

An opaque pointer that Prism delivers to the backend’s create member as the userdata member of a PrismPluginInstanceContext (see PrismPluginInstanceContext). It has the meaning the userdata parameter of prism_registry_builder_add_backend would have, and permits several descriptors that share one vtable to be distinguished at instance creation. This member MAY be NULL. Prism does not free it.

plugin_version: u64

An informational version identifying the plugin’s own release, distinct from the ABI generation and used for no compatibility decision. The value is three 16-bit components, major, minor, and patch, packed most-significant first, with the least-significant 16 bits reserved and set to zero. A plugin MAY set it to zero if it has no version to report.

Trait Implementations

impl Debug for PrismPluginBackend

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.