v4l2grab: Allow changing the capture parameters via parameters

Instead of requiring recompilation, allow passing arguments to the capture
subroutine.

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

diff --git a/contrib/test/v4l2grab.c b/contrib/test/v4l2grab.c
index de42be9..383a26e 100644 (file)
--- a/contrib/test/v4l2grab.c
+++ b/contrib/test/v4l2grab.c
@@ -22,6 +22,7 @@
 #include <sys/mman.h>
 #include <linux/videodev2.h>
 #include "../../lib/include/libv4l2.h"
+#include <argp.h>
 
 #define CLEAR(x) memset(&(x), 0, sizeof(x))
 
@@ -161,13 +162,74 @@ static int capture(char *dev_name, int x_res, int y_res, int n_frames,
        return 0;
 }
 
+/*
+ * Main routine. Basically, reads parameters via argp.h and passes it to the
+ * capture routine
+ */
+
+const char *argp_program_version = "V4L2 grabber version " V4L_UTILS_VERSION;
+const char *argp_program_bug_address = "Mauro Carvalho Chehab <mchehab@redhat.com>";
+
+static const char doc[] = "\nCapture images using libv4l, storing them as ppm files\n";
+
+static const struct argp_option options[] = {
+       {"device",      'd',    "DEV",          0,      "video device (default: /dev/video0)", 0},
+       {"out-dir",     'o',    "OUTDIR",       0,      "output directory (default: current dir)", 0},
+       {"xres",        'x',    "XRES",         0,      "horizontal resolution", 0},
+       {"yres",        'y',    "YRES",         0,      "vertical resolution", 0},
+       {"n-frames",    'n',    "NFRAMES",      0,      "number of frames to capture", 0},
+       { 0, 0, 0, 0, 0, 0 }
+};
+
+/* Static vars to store the parameters */
+static char    *dev_name = "/dev/video0";
+static char    *out_dir = ".";
+static int     x_res = 640;
+static int     y_res = 480;
+static int     n_frames = 20;
+
+static error_t parse_opt(int k, char *arg, struct argp_state *state)
+{
+       int val;
+
+       switch (k) {
+       case 'd':
+               dev_name = arg;
+               break;
+       case 'o':
+               out_dir = arg;
+               break;
+       case 'x':
+               val = atoi(arg);
+               if (val)
+                       x_res = val;
+               break;
+       case 'y':
+               val = atoi(arg);
+               if (val)
+                       y_res = val;
+               break;
+       case 'n':
+               val = atoi(arg);
+               if (val)
+                       n_frames = val;
+               break;
+       default:
+               return ARGP_ERR_UNKNOWN;
+       }
+       return 0;
+}
+
+static struct argp argp = {
+       .options = options,
+       .parser = parse_opt,
+       .doc = doc,
+};
+
+
 int main(int argc, char **argv)
 {
-       char    *dev_name = "/dev/video0";
-       char    *out_dir = ".";
-       int     x_res = 640;
-       int     y_res = 480;
-       int     n_frames = 20;
+       argp_parse(&argp, argc, argv, 0, 0, 0);
 
        return capture(dev_name, x_res, y_res, n_frames, out_dir);
 }