raspicam: Check system is running legacy camera stack

If the system is obviously configured for libcamera (for example) by
dint of /dev/video0 being given over to "unicam", complain and abort
immediately. In all other circumstances maintain previous behaviour.

(There seemed to be no obvious place for common code so it is
duplicated. There's not much.)

Signed-off-by: David Plowman <[email protected]>

host_applications/linux/apps/raspicam/RaspiStill.c

@@ -58,6 +58,10 @@ SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #include <errno.h>
 #include <sysexits.h>
 
+#include <fcntl.h>
+#include <sys/ioctl.h>
+#include <linux/videodev2.h>
+
 #include "bcm_host.h"
 #include "interface/vcos/vcos.h"
 
@@ -1629,6 +1633,23 @@ static void rename_file(RASPISTILL_STATE *state, FILE *output_file,
    }
 }
 
+static void check_camera_stack()
+{
+	int fd = open("/dev/video0", O_RDWR, 0);
+	if (fd < 0)
+		return;
+
+	struct v4l2_capability caps;
+	int ret = ioctl(fd, VIDIOC_QUERYCAP, &caps);
+	close(fd);
+
+	if (ret < 0 || strcmp((char *)caps.driver, "unicam"))
+		return;
+
+	fprintf(stderr, "ERROR: the system should be configured for the legacy camera stack\n");
+	exit(-1);
+}
+
 
 /**
  * main
@@ -1647,6 +1668,8 @@ int main(int argc, const char **argv)
    MMAL_PORT_T *encoder_input_port = NULL;
    MMAL_PORT_T *encoder_output_port = NULL;
 
+   check_camera_stack();
+
    bcm_host_init();
 
    // Register our application with the logging system

host_applications/linux/apps/raspicam/RaspiStillYUV.c

@@ -57,6 +57,10 @@ SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #include <unistd.h>
 #include <errno.h>
 
+#include <fcntl.h>
+#include <sys/ioctl.h>
+#include <linux/videodev2.h>
+
 #include "bcm_host.h"
 #include "interface/vcos/vcos.h"
 
@@ -1050,6 +1054,23 @@ static void rename_file(RASPISTILLYUV_STATE *state, FILE *output_file,
    }
 }
 
+static void check_camera_stack()
+{
+	int fd = open("/dev/video0", O_RDWR, 0);
+	if (fd < 0)
+		return;
+
+	struct v4l2_capability caps;
+	int ret = ioctl(fd, VIDIOC_QUERYCAP, &caps);
+	close(fd);
+
+	if (ret < 0 || strcmp((char *)caps.driver, "unicam"))
+		return;
+
+	fprintf(stderr, "ERROR: the system should be configured for the legacy camera stack\n");
+	exit(-1);
+}
+
 /**
  * main
  */
@@ -1066,6 +1087,8 @@ int main(int argc, const char **argv)
    MMAL_PORT_T *preview_input_port = NULL;
    FILE *output_file = NULL;
 
+   check_camera_stack();
+
    bcm_host_init();
 
    // Register our application with the logging system

host_applications/linux/apps/raspicam/RaspiVid.c

@@ -67,6 +67,10 @@ SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #include <arpa/inet.h>
 #include <time.h>
 
+#include <fcntl.h>
+#include <sys/ioctl.h>
+#include <linux/videodev2.h>
+
 #include "bcm_host.h"
 #include "interface/vcos/vcos.h"
 
@@ -2388,6 +2392,23 @@ static int wait_for_next_change(RASPIVID_STATE *state)
    return keep_running;
 }
 
+static void check_camera_stack()
+{
+	int fd = open("/dev/video0", O_RDWR, 0);
+	if (fd < 0)
+		return;
+
+	struct v4l2_capability caps;
+	int ret = ioctl(fd, VIDIOC_QUERYCAP, &caps);
+	close(fd);
+
+	if (ret < 0 || strcmp((char *)caps.driver, "unicam"))
+		return;
+
+	fprintf(stderr, "ERROR: the system should be configured for the legacy camera stack\n");
+	exit(-1);
+}
+
 /**
  * main
  */
@@ -2408,6 +2429,8 @@ int main(int argc, const char **argv)
    MMAL_PORT_T *splitter_output_port = NULL;
    MMAL_PORT_T *splitter_preview_port = NULL;
 
+   check_camera_stack();
+
    bcm_host_init();
 
    // Register our application with the logging system

host_applications/linux/apps/raspicam/RaspiVidYUV.c

@@ -64,6 +64,10 @@ SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #include <netinet/in.h>
 #include <arpa/inet.h>
 
+#include <fcntl.h>
+#include <sys/ioctl.h>
+#include <linux/videodev2.h>
+
 #include "bcm_host.h"
 #include "interface/vcos/vcos.h"
 
@@ -1224,6 +1228,23 @@ static int wait_for_next_change(RASPIVIDYUV_STATE *state)
    return keep_running;
 }
 
+static void check_camera_stack()
+{
+	int fd = open("/dev/video0", O_RDWR, 0);
+	if (fd < 0)
+		return;
+
+	struct v4l2_capability caps;
+	int ret = ioctl(fd, VIDIOC_QUERYCAP, &caps);
+	close(fd);
+
+	if (ret < 0 || strcmp((char *)caps.driver, "unicam"))
+		return;
+
+	fprintf(stderr, "ERROR: the system should be configured for the legacy camera stack\n");
+	exit(-1);
+}
+
 /**
  * main
  */
@@ -1239,6 +1260,8 @@ int main(int argc, const char **argv)
    MMAL_PORT_T *camera_still_port = NULL;
    MMAL_PORT_T *preview_input_port = NULL;
 
+   check_camera_stack();
+
    bcm_host_init();
 
    // Register our application with the logging system