hal: Fix comparison of integers of different signs

The CameraHalManager::getCameraInfo() validates the camera id it
receives from the camera service, and in doing so compares it with an
unsigned integer, generating a compiler error:

src/android/camera_hal_manager.cpp:121:9: error: comparison of integers of different signs: 'int' and 'unsigned int' [-Werror,-Wsign-compare]
        if (id >= numCameras() || id < 0) {
            ~~ ^  ~~~~~~~~~~~~

Fix this by turning the id into an unsigned int, as camera ids can't be
negative. If a negative id is received from the camera service it will
be converted to a large unsigned integer that will fail the comparison
with numCameras().

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>

2 files changed, 3 insertions, 3 deletions

diff --git a/src/android/camera_hal_manager.cpp b/src/android/camera_hal_manager.cpp
index 08c759df..1e66f632 100644
--- a/src/android/camera_hal_manager.cpp
+++ b/src/android/camera_hal_manager.cpp
@@ -113,12 +113,12 @@ unsigned int CameraHalManager::numCameras() const
 	return cameraManager_->cameras().size();
 }
 
-int CameraHalManager::getCameraInfo(int id, struct camera_info *info)
+int CameraHalManager::getCameraInfo(unsigned int id, struct camera_info *info)
 {
 	if (!info)
 		return -EINVAL;
 
-	if (id >= numCameras() || id < 0) {
+	if (id >= numCameras()) {
 		LOG(HAL, Error) << "Invalid camera id '" << id << "'";
 		return -EINVAL;
 	}
diff --git a/src/android/camera_hal_manager.h b/src/android/camera_hal_manager.h
index 8004aaf6..8228623a 100644
--- a/src/android/camera_hal_manager.h
+++ b/src/android/camera_hal_manager.h
@@ -30,7 +30,7 @@ public:
 	int close(CameraProxy *proxy);
 
 	unsigned int numCameras() const;
-	int getCameraInfo(int id, struct camera_info *info);
+	int getCameraInfo(unsigned int id, struct camera_info *info);
 
 private:
 	void run() override;