media-gfx/zbar: fix UVC webcam compatibility (bug 548034, thanks Scott Alfter).

Package-Manager: portage-2.2.20

1 files changed, 49 insertions, 0 deletions

diff --git a/media-gfx/zbar/files/zbar-0.10-v4l2-uvcvideo.patch b/media-gfx/zbar/files/zbar-0.10-v4l2-uvcvideo.patch
new file mode 100644
index 000000000000..4fde95e2b563
--- /dev/null
+++ b/media-gfx/zbar/files/zbar-0.10-v4l2-uvcvideo.patch
@@ -0,0 +1,49 @@
+--- zbar-0.10/zbar/video/v4l2.c	2009-10-23 18:16:44.000000000 +0000
++++ zbar-0.10/zbar/video/v4l2.c	2015-03-07 05:46:36.000000000 +0000
+@@ -241,6 +241,21 @@
+     return(0);
+ }
+ 
++static int v4l2_request_buffers (zbar_video_t *vdo)
++{
++    struct v4l2_requestbuffers rb;
++    memset(&rb, 0, sizeof(rb));
++    rb.count = vdo->num_images;
++    rb.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
++    rb.memory = V4L2_MEMORY_USERPTR;
++    if(ioctl(vdo->fd, VIDIOC_REQBUFS, &rb) < 0)
++        return(err_capture(vdo, SEV_ERROR, ZBAR_ERR_SYSTEM, __func__,
++                           "requesting video frame buffers (VIDIOC_REQBUFS)"));
++    if(rb.count) 
++        vdo->num_images = rb.count;
++    return(0);
++}
++
+ static int v4l2_set_format (zbar_video_t *vdo,
+                             uint32_t fmt)
+ {
+@@ -308,6 +323,8 @@
+         return(-1);
+     if(vdo->iomode == VIDEO_MMAP)
+         return(v4l2_mmap_buffers(vdo));
++    if(vdo->iomode == VIDEO_USERPTR)
++        return(v4l2_request_buffers(vdo));
+     return(0);
+ }
+ 
+@@ -337,8 +354,13 @@
+     else {
+         if(!vdo->iomode)
+             vdo->iomode = VIDEO_USERPTR;
+-        if(rb.count)
+-            vdo->num_images = rb.count;
++        /* releasing buffers 
++         * lest the driver may later refuse to change format
++         */
++        rb.count = 0;
++        if (ioctl(vdo->fd, VIDIOC_REQBUFS, &rb) < 0)
++            zprintf(0, "WARNING: releasing video buffers failed: error %d\n",
++                errno);
+     }
+     return(0);
+ }