feat: 初步增加 Windows 支持

src/video/signal.rs

@@ -0,0 +1,47 @@
+//! Video signal status classification.
+
+/// Fine-grained signal status reported by CSI/HDMI bridge devices.
+///
+/// Only `rk_hdmirx` / `rkcif` / tc358743-class bridges can distinguish these
+/// via `VIDIOC_QUERY_DV_TIMINGS` errno; USB UVC devices always report `Ok`
+/// until they fail with a generic timeout.
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum SignalStatus {
+    /// HDMI cable physically disconnected (`ENOLINK`).
+    NoCable,
+    /// TMDS signal present but timings cannot be locked (`ENOLCK`).
+    NoSync,
+    /// Timings outside of hardware capability (`ERANGE`).
+    OutOfRange,
+    /// Generic "no usable source" (fallback for EINVAL / EIO / unknown errnos).
+    NoSignal,
+    /// UVC/USB isochronous protocol error (common kernel: status -71 / userspace EPROTO).
+    UvcUsbError,
+    /// UVC capture stalled (repeated DQBUF timeouts; often cable, hub, or controller load).
+    UvcCaptureStall,
+}
+
+impl SignalStatus {
+    pub fn as_str(self) -> &'static str {
+        match self {
+            SignalStatus::NoCable => "no_cable",
+            SignalStatus::NoSync => "no_sync",
+            SignalStatus::OutOfRange => "out_of_range",
+            SignalStatus::NoSignal => "no_signal",
+            SignalStatus::UvcUsbError => "uvc_usb_error",
+            SignalStatus::UvcCaptureStall => "uvc_capture_stall",
+        }
+    }
+
+    pub fn from_str(s: &str) -> Option<Self> {
+        Some(match s {
+            "no_cable" => SignalStatus::NoCable,
+            "no_sync" => SignalStatus::NoSync,
+            "out_of_range" => SignalStatus::OutOfRange,
+            "no_signal" => SignalStatus::NoSignal,
+            "uvc_usb_error" => SignalStatus::UvcUsbError,
+            "uvc_capture_stall" => SignalStatus::UvcCaptureStall,
+            _ => return None,
+        })
+    }
+}