webcamd/cuse4bsd && Skype

[Matthias Apitz]

El día Thursday, January 05, 2012 a las 07:00:01PM +0100, Hans Petter Selasky escribió:

> > OK concerning HAL, but the main question is why the V4L IOCTL are not
> > translated into V4L2? where should I look? thanks
> 
> They are, but probably the structure size is wrong.
> 
> --HPS

Hello Hans,

I have below a gdb session of the 1st failing IOCTL after the open; does
not look like a problem of the structure size; the error is returned
from the call

	ret = vdev->fops->unlocked_ioctl(filp, cmd, arg);
	
let me know if you need more details of the gdb session; thanks

	matthias

# gdb work/webcamd-3.2.0.1/webcamd
...
(gdb) br v4b_ioctl
Breakpoint 1 at 0x82f2c96: file webcamd.c, line 265.
(gdb) r
Starting program: /usr/ports/multimedia/webcamd/work/webcamd-3.2.0.1/webcamd 

(now Skype in another session)

mydebug: v4b_open fflags: 00000003
mydebug: linux_open gives: handle=28c08600
[Switching to Thread 28805180 (LWP 100240)]

Breakpoint 1, v4b_ioctl (cdev=0x2882c0c0, fflags=7, cmd=1074034177, peer_data=0x10000)
    at webcamd.c:265
265             printf("mydebug: v4b_ioctl: cmd=0x%08x\n", cmd);
(gdb) n
mydebug: v4b_ioctl: cmd=0x40047601
266             handle = cuse_dev_get_per_file_handle(cdev);
(gdb) n
267             printf("mydebug: v4b_ioctl: handle=%08x cmd=0x%08x\n", handle, cmd);
(gdb) n
mydebug: v4b_ioctl: handle=28c08600 cmd=0x40047601
270             if (cmd == FIONBIO || cmd == FIOASYNC)
(gdb) n
274             error = linux_ioctl(handle, fflags & CUSE_FFLAG_NONBLOCK,
(gdb) s
linux_ioctl (handle=0x28c08600, fflags=4, cmd=1074034177, arg=0x10000)
    at kernel/linux_file.c:114
114             if (handle == NULL)
(gdb) n
117             linux_fix_f_flags(&handle->fixed_file, fflags);
(gdb) n
119             if (handle->fixed_file.f_op->unlocked_ioctl != NULL)
(gdb) n
120                     return (handle->fixed_file.f_op->unlocked_ioctl(&handle->fixed_file,
(gdb) s
v4l2_ioctl (filp=0x28c08608, cmd=1074034177, arg=65536)
    at media_tree/drivers/media/video/v4l2-dev.c:333
333             struct video_device *vdev = video_devdata(filp);
(gdb) n
334             int ret = -ENODEV;
(gdb) n
336             if (vdev->fops->unlocked_ioctl) {
(gdb) n
337                     if (vdev->lock && mutex_lock_interruptible(vdev->lock))
(gdb) n
339                     if (video_is_registered(vdev))
(gdb) n
340                             ret = vdev->fops->unlocked_ioctl(filp, cmd, arg);
(gdb) n
341                     if (vdev->lock)
(gdb) p ret
$1 = -22
(gdb) n
379             if (ret == 0 && cmd == VIDIOC_ENUMINPUT) {
(gdb) n
397             return ret;
(gdb) n
398     }
(gdb) n
linux_ioctl (handle=0x28c08600, fflags=4, cmd=1074034177, arg=0x10000)
    at kernel/linux_file.c:127
127     }
(gdb) n
v4b_ioctl (cdev=0x2882c0c0, fflags=7, cmd=1074034177, peer_data=0x10000)
    at webcamd.c:276
276             printf("mydebug: linux_ioctl returns: error=%08x\n", error);
(gdb) n
mydebug: linux_ioctl returns: error=ffffffea

-- 
Matthias Apitz
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