1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
use std::io;
use crate::buffers::UserBufferManager;
use crate::v4l2;
use crate::v4l_sys::*;
use crate::{BufferManager, BufferStream, Device, UserBuffer};
pub struct UserBufferStream<'a> {
dev: &'a dyn Device,
manager: UserBufferManager<'a>,
active: bool,
}
impl<'a> UserBufferStream<'a> {
pub fn new(dev: &'a dyn Device) -> io::Result<Self> {
UserBufferStream::with_buffers(dev, 4)
}
pub fn with_buffers(dev: &'a dyn Device, count: u32) -> io::Result<Self> {
let mut manager = UserBufferManager::new(dev);
manager.allocate(count)?;
Ok(UserBufferStream {
dev,
manager,
active: false,
})
}
}
impl<'a> Drop for UserBufferStream<'a> {
fn drop(&mut self) {
self.stop().unwrap();
}
}
impl<'a> BufferStream for UserBufferStream<'a> {
type Buffer = UserBuffer<'a>;
fn active(&self) -> bool {
self.active
}
fn start(&mut self) -> io::Result<()> {
unsafe {
let mut typ = v4l2_buf_type_V4L2_BUF_TYPE_VIDEO_CAPTURE;
v4l2::ioctl(
self.dev.fd(),
v4l2::vidioc::VIDIOC_STREAMON,
&mut typ as *mut _ as *mut std::os::raw::c_void,
)?;
}
Ok(())
}
fn stop(&mut self) -> io::Result<()> {
unsafe {
let mut typ = v4l2_buf_type_V4L2_BUF_TYPE_VIDEO_CAPTURE;
v4l2::ioctl(
self.dev.fd(),
v4l2::vidioc::VIDIOC_STREAMOFF,
&mut typ as *mut _ as *mut std::os::raw::c_void,
)?;
}
Ok(())
}
fn queue(&mut self) -> io::Result<()> {
self.manager.queue()
}
fn dequeue(&mut self) -> io::Result<Self::Buffer> {
self.manager.dequeue()
}
}
impl<'a> Iterator for UserBufferStream<'a> {
type Item = UserBuffer<'a>;
fn next(&mut self) -> Option<Self::Item> {
if !self.active && self.start().is_err() {
return None;
}
let buf = self.dequeue();
if buf.is_err() {
return None;
}
let res = self.queue();
if res.is_err() {
return None;
}
Some(buf.unwrap())
}
}