Files
forge-steel/src/video.c
T

269 lines
7.3 KiB
C

#include <errno.h>
#include <fcntl.h>
#include <linux/videodev2.h>
#include <sys/ioctl.h>
#include <unistd.h>
#include "logs.h"
#include "types.h"
#include "video.h"
static void ioctl_error(VideoDevice *device, const char *operation,
const char *default_msg) {
if (errno == EINVAL) {
log_warn("(%s) %s -> EINVAL: %s", device->name, operation, default_msg);
} else if (errno == EAGAIN) {
log_warn("(%s) %s -> EAGAIN: device state invalid", operation,
device->name);
} else if (errno == EBADF) {
log_warn("(%s) %s -> EBADF: file descriptor invalid", operation,
device->name);
} else if (errno == EBUSY) {
log_warn("(%s) %s -> EBUSY: device is busy", device->name, operation);
} else if (errno == EFAULT) {
log_warn("(%s) %s -> EFAULT: invalid pointer", device->name, operation);
} else if (errno == ENODEV) {
log_warn("(%s) %s -> ENODEV: device not found", device->name, operation);
} else if (errno == ENOMEM) {
log_warn("(%s) %s -> ENOMEM: not enough memory", device->name, operation);
} else if (errno == ENOTTY) {
log_warn("(%s) %s -> ENOTTY: ioctl not supported by file descriptor",
device->name, operation);
} else if (errno == ENOSPC) {
log_warn("(%s) %s -> ENOSPC: USB bandwidth error", device->name, operation);
} else if (errno == EPERM) {
log_warn("(%s) %s -> EPERM: permission denied", device->name, operation);
} else if (errno == EIO) {
log_warn("(%s) %s -> EIO: I/O error", device->name, operation);
} else if (errno == ENXIO) {
log_warn("(%s) %s -> ENXIO: no device exists", device->name, operation);
} else if (errno == EPIPE) {
log_warn("(%s) %s -> EPIPE: pipeline error", device->name, operation);
} else if (errno == ENOLINK) {
log_warn("(%s) %s -> ENOLINK: pipeline configuration invalid for Media "
"Controller interface",
device->name, operation);
} else {
log_error("(%s) %s unknown error %d", device->name, operation, errno);
}
device->error = true;
}
static VideoDevice open_device(char *name) {
VideoDevice device;
device.name = name;
device.error = false;
device.fd = -1;
device.fd = open(name, O_RDWR);
if (device.fd == -1) {
log_warn("(%s) Cannot open device", name);
device.error = true;
}
return device;
}
static bool check_device_caps(VideoDevice *device) {
struct v4l2_capability cap;
memset(&cap, 0, sizeof(cap));
if (ioctl(device->fd, VIDIOC_QUERYCAP, &cap) == -1) {
ioctl_error(device, "VIDIOC_QUERYCAP", "Not a V4L2 device");
return false;
}
if (!(cap.capabilities & V4L2_CAP_VIDEO_CAPTURE)) {
log_warn("(%s) Not a video capture device", device->name);
device->error = true;
return false;
}
if (!(cap.capabilities & V4L2_CAP_STREAMING)) {
log_warn("(%s) No streaming i/o support", device->name);
device->error = true;
return false;
}
return true;
}
static bool set_device_format(VideoDevice *device, unsigned int preferred_width,
unsigned int preferred_height) {
struct v4l2_format fmt;
device->output = false;
memset(&fmt, 0, sizeof(fmt));
fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
fmt.fmt.pix.width = preferred_width;
fmt.fmt.pix.height = preferred_height;
fmt.fmt.pix.pixelformat = V4L2_PIX_FMT_YUYV;
fmt.fmt.pix.field = V4L2_FIELD_INTERLACED;
if (ioctl(device->fd, VIDIOC_S_FMT, &fmt) == -1) {
fmt.type = V4L2_BUF_TYPE_VIDEO_OUTPUT;
device->output = true;
if (ioctl(device->fd, VIDIOC_S_FMT, &fmt) == -1) {
ioctl_error(device, "VIDIOC_S_FMT",
"Requested buffer type not supported");
return false;
}
}
device->width = fmt.fmt.pix.width;
device->height = fmt.fmt.pix.height;
device->pixelformat = fmt.fmt.pix.pixelformat;
device->bytesperline = fmt.fmt.pix.bytesperline;
log_info("(%s) Format fourcc: %c%c%c%c", device->name,
fmt.fmt.pix.pixelformat, fmt.fmt.pix.pixelformat >> 8,
fmt.fmt.pix.pixelformat >> 16, fmt.fmt.pix.pixelformat >> 24);
log_info("(%s) Resolution: %dx%d", device->name, fmt.fmt.pix.width,
fmt.fmt.pix.height);
return true;
}
static bool request_buffers(VideoDevice *device) {
struct v4l2_requestbuffers reqbuf;
memset(&reqbuf, 0, sizeof(reqbuf));
reqbuf.type =
device->output ? V4L2_BUF_TYPE_VIDEO_OUTPUT : V4L2_BUF_TYPE_VIDEO_CAPTURE;
reqbuf.memory = V4L2_MEMORY_MMAP;
reqbuf.count = 1;
if (ioctl(device->fd, VIDIOC_REQBUFS, &reqbuf) == -1) {
ioctl_error(device, "VIDIOC_REQBUFS",
"Buffer type or I/O method not supported");
return false;
}
log_info("(%s) V4L2 Buffer Count: %d", device->name, reqbuf.count);
return true;
}
static bool export_buffer(VideoDevice *device) {
struct v4l2_exportbuffer expbuf;
device->exp_fd = -1;
memset(&expbuf, 0, sizeof(expbuf));
expbuf.type =
device->output ? V4L2_BUF_TYPE_VIDEO_OUTPUT : V4L2_BUF_TYPE_VIDEO_CAPTURE;
expbuf.index = 0;
expbuf.flags = O_RDONLY;
if (ioctl(device->fd, VIDIOC_EXPBUF, &expbuf) == -1) {
ioctl_error(
device, "VIDIOC_EXPBUF",
"A queue is not in MMAP mode or DMABUF exporting is not supported");
return false;
}
device->exp_fd = expbuf.fd;
return true;
}
static const enum v4l2_buf_type buf_type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
static bool open_stream(VideoDevice *device) {
if (ioctl(device->fd, VIDIOC_STREAMON, &buf_type) == -1) {
ioctl_error(
device, "VIDIOC_STREAMON",
"Buffer type not supported or no buffer allocated or enqueued yet");
return false;
}
return true;
}
static void create_image_buffer(VideoDevice *device) {
memset(&device->buf, 0, sizeof(device->buf));
device->buf.type =
device->output ? V4L2_BUF_TYPE_VIDEO_OUTPUT : V4L2_BUF_TYPE_VIDEO_CAPTURE;
device->buf.memory = V4L2_MEMORY_MMAP;
device->buf.index = 0;
ioctl(device->fd, VIDIOC_QBUF, &device->buf);
}
static void close_stream(VideoDevice device) {
ioctl(device.fd, VIDIOC_STREAMOFF, &buf_type);
}
VideoDevice video_init(char *name, unsigned int preferred_width,
unsigned int preferred_height) {
VideoDevice device;
device = open_device(name);
if (device.error) {
return device;
}
if (!check_device_caps(&device)) {
return device;
}
if (!set_device_format(&device, preferred_width, preferred_height)) {
return device;
}
if (!request_buffers(&device)) {
return device;
}
if (!export_buffer(&device)) {
return device;
}
if (!open_stream(&device)) {
return device;
}
create_image_buffer(&device);
return device;
}
bool video_read(VideoDevice *device) {
if (ioctl(device->fd, VIDIOC_DQBUF, &device->buf) == -1) {
ioctl_error(device, "VIDIOC_DQBUF",
"buffer type not supported or no buffer allocated or the index "
"is out of bounds");
return false;
}
if (ioctl(device->fd, VIDIOC_QBUF, &device->buf) == -1) {
ioctl_error(device, "VIDIOC_QBUF",
"buffer type not supported or no buffer allocated or the index "
"is out of bounds");
return false;
}
return true;
}
void video_free(VideoDevice device) {
if (!device.error) {
close_stream(device);
}
if (device.exp_fd != -1) {
close(device.exp_fd);
}
if (device.fd != -1) {
close(device.fd);
}
}