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use std::marker::PhantomData; use std::ptr; use device; use ffi::*; use format::context::common::Context; use libc::c_int; use Error; impl Context { pub fn devices(&self) -> Result<DeviceIter, Error> { unsafe { DeviceIter::wrap(self.as_ptr()) } } } pub struct DeviceIter<'a> { ptr: *mut AVDeviceInfoList, cur: c_int, _marker: PhantomData<&'a ()>, } impl<'a> DeviceIter<'a> { pub unsafe fn wrap(ctx: *const AVFormatContext) -> Result<Self, Error> { let mut ptr: *mut AVDeviceInfoList = ptr::null_mut(); match avdevice_list_devices(ctx as *mut _, &mut ptr) { n if n < 0 => Err(Error::from(n)), _ => Ok(DeviceIter { ptr, cur: 0, _marker: PhantomData, }), } } } impl<'a> DeviceIter<'a> { pub fn default(&self) -> usize { unsafe { (*self.ptr).default_device as usize } } } impl<'a> Drop for DeviceIter<'a> { fn drop(&mut self) { unsafe { avdevice_free_list_devices(&mut self.ptr); } } } impl<'a> Iterator for DeviceIter<'a> { type Item = device::Info<'a>; fn next(&mut self) -> Option<<Self as Iterator>::Item> { unsafe { if self.cur >= (*self.ptr).nb_devices { None } else { self.cur += 1; Some(device::Info::wrap( *(*self.ptr).devices.offset((self.cur - 1) as isize), )) } } } fn size_hint(&self) -> (usize, Option<usize>) { unsafe { let length = (*self.ptr).nb_devices as usize; (length - self.cur as usize, Some(length - self.cur as usize)) } } } impl<'a> ExactSizeIterator for DeviceIter<'a> {}