Quiet expected error cases

src/drivers/v4l2/v4l2device.cpp

@@ -93,13 +93,14 @@ void V4L2Device::__ioctl(uint64_t ctl, void* data, const QString& errorLabel) co
     //qDebug() << "IOCTL RUN: %1 with result %2"_q % d->ioctl_names.value(ctl, "%1"_q % ctl) % r;
 }
 
-int V4L2Device::__xioctl(uint64_t ctl, void* data, const QString& errorLabel) const
+int V4L2Device::__xioctl(uint64_t ctl, void* data, const QString &errorLabel, int ok_errno) const
 {
   try {
     this->ioctl(ctl, data, errorLabel);
     return 0;
   } catch(const V4L2Exception &e) {
-    qWarning() << e.what();
+    if (errno != ok_errno)
+      qWarning() << e.what();
     return -1;
   }
 }

src/drivers/v4l2/v4l2device.h

@@ -33,11 +33,17 @@ class V4L2Device {
   inline operator bool() const;
   int descriptor() const;
 
-  template<typename T> void ioctl(uint64_t ctl, T *data, const QString &errorLabel = {}) const { return __ioctl(ctl, reinterpret_cast<void*>(data), errorLabel); }
-  template<typename T> int xioctl(uint64_t ctl, T *data, const QString &errorLabel = {}) const { return __xioctl(ctl, reinterpret_cast<void*>(data), errorLabel); }
+  template<typename T> void ioctl(uint64_t ctl, T *data, const QString &errorLabel = {}) const {
+    return __ioctl(ctl, reinterpret_cast<void*>(data), errorLabel);
+  }
+
+  template<typename T> int xioctl(uint64_t ctl, T *data, const QString &errorLabel = {}, int ok_errno = 0) const {
+    return __xioctl(ctl, reinterpret_cast<void*>(data), errorLabel, ok_errno);
+  }
+
 private:
   void __ioctl(uint64_t ctl, void *data, const QString &errorLabel) const;
-  int __xioctl(uint64_t ctl, void *data, const QString &errorLabel) const;
+  int __xioctl(uint64_t ctl, void *data, const QString &errorLabel, int ok_errno) const;
   DPTR
 };
 

src/drivers/v4l2/v4l2formats.cpp

@@ -59,8 +59,9 @@ V4L2Formats::V4L2Formats(const V4L2DevicePtr& device) : dptr(device)
   v4l2_fmtdesc formats;
   formats.index = 0;
   formats.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
-  for(formats.index = 0; 0 ==device->xioctl(VIDIOC_ENUM_FMT, &formats); formats.index++) {
+  while (0 == device->xioctl(VIDIOC_ENUM_FMT, &formats, {}, EINVAL)) {
     d->formats.push_back(make_shared<V4L2Format>(formats, device));
+    formats.index++;
   }
   for(auto format: d->formats)
     qDebug() << "Found format: " << *format;
@@ -106,9 +107,11 @@ V4L2ResolutionPtr V4L2Formats::current_resolution() const
 V4L2Format::V4L2Format(const v4l2_fmtdesc &fmtdesc, const V4L2DevicePtr &device) : dptr(fmtdesc, device)
 {
   v4l2_frmsizeenum frmsize;
+  frmsize.index = 0;
   frmsize.pixel_format = fmtdesc.pixelformat;
-  for(frmsize.index = 0; device->xioctl(VIDIOC_ENUM_FRAMESIZES, &frmsize, "querying resolutions") >= 0; frmsize.index++) {
+  while (device->xioctl(VIDIOC_ENUM_FRAMESIZES, &frmsize, "querying resolutions", EINVAL) >= 0) {
     d->resolutions.push_back(make_shared<V4L2Resolution>(frmsize, device, *this));
+    frmsize.index++;
   }
 }
 

src/drivers/v4l2/v4l2imagingworker.cpp

@@ -102,9 +102,10 @@ void V4L2ImagingWorker::Private::adjust_framerate()
     fps_s.height = format.fmt.pix.height;
     fps_s.pixel_format = format.fmt.pix.pixelformat;
     qDebug() << "scanning for fps with pixel format " << FOURCC2QS(fps_s.pixel_format);
-    for(fps_s.index = 0; device->xioctl(VIDIOC_ENUM_FRAMEINTERVALS, &fps_s) >= 0; fps_s.index++) {
+    while (device->xioctl(VIDIOC_ENUM_FRAMEINTERVALS, &fps_s, {}, EINVAL) >= 0) {
       qDebug() << "found fps: " << fps_s;
       rates.push_back(fps_s);
+      fps_s.index++;
     }
     auto ratio = [=](const v4l2_frmivalenum &a) { return static_cast<double>(a.discrete.numerator)/static_cast<double>(a.discrete.denominator); };
     sort(begin(rates), end(rates), [&](const v4l2_frmivalenum &a, const v4l2_frmivalenum &b){ return ratio(a) < ratio(b);} );