Struct v4l::io::dmabuf::arena::Arena

pub struct Arena<T: EntryBuffer>
where
    Self: DmabufRelease,
{
    handle: Arc<Handle>,
    bufs: Vec<T>,
    buf_type: Type,
}

Manage dmabuf buffers

All buffers are released in the Drop impl.

Fields

handle: Arc<Handle>

bufs: Vec<T>

buf_type: Type

Implementations

impl<T: EntryBuffer> Arena<T>

where Self: DmabufRelease,

pub fn new(handle: Arc<Handle>, buf_type: Type) -> Self

Returns a new buffer manager instance

You usually do not need to use this directly. A UserBufferStream creates its own manager instance by default.

Arguments

• handle - Device handle to get its file descriptor
• buf_type - Type of the buffers

fn requestbuffers_desc(&self) -> v4l2_requestbuffers

pub fn allocate(&mut self, count: u32) -> Result<u32>

Returns the number of buffers present in the arena (same as the number in self.bufs).

pub fn len(&self) -> usize

impl Arena<DmaBuf>

pub fn get_dmabuf(&mut self, index: usize) -> Result<&DmaBuf, &'static str>

Returns the buffer for this index

pub fn get_dmabuf_mut( &mut self, index: usize, ) -> Result<&mut DmaBuf, &'static str>

Returns the buffer for this index

impl Arena<EntryDmaBufProtected>

pub fn replace_buffer( &mut self, buf: DmaBufProtected, ) -> Result<usize, (DmaBufProtected, &'static str)>

Finds the kernel index for this buffer and places it there. Doesn’t check if the buffer was there already. Returns the kernel index.

pub fn take_buffer( &mut self, index: usize, ) -> Result<DmaBufProtected, &'static str>

Removes and returns buffer at this kernel index.

pub fn get_dmabuf_mut( &mut self, index: usize, ) -> Result<&mut DmaBuf, &'static str>

Returns a writeably-locked buffer for this index

pub unsafe fn force_release(&mut self) -> Result<()>

Release buffers without checking if any buffers are gone missing.

What makes this unsafe is that the buffers out there may become unuseable (TODO: check semantics). See V4L2_BUF_CAP_SUPPORTS_ORPHANED_BUFS.

Trait Implementations

impl DmabufRelease for Arena<DmaBuf>

fn release(&mut self) -> Result<()>

impl DmabufRelease for Arena<EntryDmaBufProtected>

fn release(&mut self) -> Result<()>

impl<T: EntryBuffer> Drop for Arena<T>

where Self: DmabufRelease,

fn drop(&mut self)

Executes the destructor for this type.