ffmpeg_next/device/
extensions.rs

1use std::marker::PhantomData;
2use std::ptr;
3
4use crate::Error;
5use crate::device;
6use crate::ffi::*;
7use crate::format::context::common::Context;
8use libc::c_int;
9
10impl Context {
11    pub fn devices(&self) -> Result<DeviceIter<'_>, Error> {
12        unsafe { DeviceIter::wrap(self.as_ptr()) }
13    }
14}
15
16pub struct DeviceIter<'a> {
17    ptr: *mut AVDeviceInfoList,
18    cur: c_int,
19
20    _marker: PhantomData<&'a ()>,
21}
22
23impl<'a> DeviceIter<'a> {
24    pub unsafe fn wrap(ctx: *const AVFormatContext) -> Result<Self, Error> {
25        unsafe {
26            let mut ptr: *mut AVDeviceInfoList = ptr::null_mut();
27
28            match avdevice_list_devices(ctx as *mut _, &mut ptr) {
29                n if n < 0 => Err(Error::from(n)),
30
31                _ => Ok(DeviceIter {
32                    ptr,
33                    cur: 0,
34                    _marker: PhantomData,
35                }),
36            }
37        }
38    }
39}
40
41impl<'a> DeviceIter<'a> {
42    pub fn default(&self) -> usize {
43        unsafe { (*self.ptr).default_device as usize }
44    }
45}
46
47impl<'a> Drop for DeviceIter<'a> {
48    fn drop(&mut self) {
49        unsafe {
50            avdevice_free_list_devices(&mut self.ptr);
51        }
52    }
53}
54
55impl<'a> Iterator for DeviceIter<'a> {
56    type Item = device::Info<'a>;
57
58    fn next(&mut self) -> Option<<Self as Iterator>::Item> {
59        unsafe {
60            if self.cur >= (*self.ptr).nb_devices {
61                None
62            } else {
63                self.cur += 1;
64                Some(device::Info::wrap(
65                    *(*self.ptr).devices.offset((self.cur - 1) as isize),
66                ))
67            }
68        }
69    }
70
71    fn size_hint(&self) -> (usize, Option<usize>) {
72        unsafe {
73            let length = (*self.ptr).nb_devices as usize;
74
75            (length - self.cur as usize, Some(length - self.cur as usize))
76        }
77    }
78}
79
80impl<'a> ExactSizeIterator for DeviceIter<'a> {}
ffmpeg_next/device/extensions.rs

ffmpeg_next/device/
extensions.rs
