void common_process_controls(int fd)
{
	find_controls(fd);
	for (ctrl_get_list::iterator iter = get_ctrls.begin(); iter != get_ctrls.end(); ++iter) {
	    if (ctrl_str2q.find(*iter) == ctrl_str2q.end()) {
		fprintf(stderr, "unknown control '%s'\n", iter->c_str());
		exit(1);
	    }
	}
	for (ctrl_set_map::iterator iter = set_ctrls.begin(); iter != set_ctrls.end(); ++iter) {
	    if (ctrl_str2q.find(iter->first) == ctrl_str2q.end()) {
		fprintf(stderr, "unknown control '%s'\n", iter->first.c_str());
		exit(1);
	    }
	}
}
void common_process_controls(int fd)
{
	struct v4l2_query_ext_ctrl qc = {
		V4L2_CTRL_FLAG_NEXT_CTRL | V4L2_CTRL_FLAG_NEXT_COMPOUND
	};
	int rc;

	rc = test_ioctl(fd, VIDIOC_QUERY_EXT_CTRL, &qc);
	have_query_ext_ctrl = rc == 0;

	find_controls(fd);
	for (ctrl_get_list::iterator iter = get_ctrls.begin(); iter != get_ctrls.end(); ++iter) {
	    if (ctrl_str2q.find(*iter) == ctrl_str2q.end()) {
		fprintf(stderr, "unknown control '%s'\n", iter->c_str());
		exit(1);
	    }
	}
	for (ctrl_set_map::iterator iter = set_ctrls.begin(); iter != set_ctrls.end(); ++iter) {
	    if (ctrl_str2q.find(iter->first) == ctrl_str2q.end()) {
		fprintf(stderr, "unknown control '%s'\n", iter->first.c_str());
		exit(1);
	    }
	}
}
int main(int argc, char **argv)
{
	char *value, *subs;
	int i;

	int fd = -1;


	/* command args */
	int ch;
	const char *device = "/dev/video0";	/* -d device */
	struct v4l2_capability vcap;	/* list_cap */
	char short_options[26 * 2 * 2 + 1];
	int idx = 0;


	if (argc == 1) {
		usage();
		return 0;
	}
	for (i = 0; long_options[i].name; i++) {
		if (!isalpha(long_options[i].val))
			continue;
		short_options[idx++] = long_options[i].val;
		if (long_options[i].has_arg == required_argument)
			short_options[idx++] = ':';
	}
	while (1) {
		int option_index = 0;

		short_options[idx] = 0;
		ch = getopt_long(argc, argv, short_options,
				 long_options, &option_index);
		if (ch == -1)
			break;

		options[(int)ch] = 1;
		switch (ch) {
		case OptHelp:
			usage();
			return 0;
		case OptSetDevice:
			device = optarg;
			if (device[0] >= '0' && device[0] <= '9' && device[1] == 0) {
				static char newdev[20];
				char dev = device[0];

				sprintf(newdev, "/dev/video%c", dev);
				device = newdev;
			}
			break;
		case OptGetCtrl:
			subs = optarg;
			while (*subs != '\0') {
				parse_next_subopt(&subs, &value);
				if (strchr(value, '=')) {
				    usage();
				    exit(1);
				}
				else {
				    get_ctrls.push_back(value);
				}
			}
			break;
		case OptSetCtrl:
			subs = optarg;
			while (*subs != '\0') {
				parse_next_subopt(&subs, &value);
				if (const char *equal = strchr(value, '=')) {
				    set_ctrls[std::string(value, (equal - value))] = equal + 1;
				}
				else {
				    fprintf(stderr, "control '%s' without '='\n", value);
				    exit(1);
				}
			}
			break;
		case ':':
			fprintf(stderr, "Option `%s' requires a value\n",
				argv[optind]);
			usage();
			return 1;
		case '?':
			fprintf(stderr, "Unknown argument `%s'\n",
				argv[optind]);
			usage();
			return 1;
		}
	}
	if (optind < argc) {
		printf("unknown arguments: ");
		while (optind < argc)
			printf("%s ", argv[optind++]);
		printf("\n");
		usage();
		return 1;
	}

	if ((fd = open(device, O_RDWR)) < 0) {
		fprintf(stderr, "Failed to open %s: %s\n", device,
			strerror(errno));
		exit(1);
	}

	doioctl(fd, VIDIOC_QUERYCAP, &vcap, "VIDIOC_QUERYCAP");
	capabilities = vcap.capabilities;
	find_controls(fd);
	for (ctrl_get_list::iterator iter = get_ctrls.begin(); iter != get_ctrls.end(); ++iter) {
	    if (ctrl_str2id.find(*iter) == ctrl_str2id.end()) {
		fprintf(stderr, "unknown control '%s'\n", (*iter).c_str());
		exit(1);
	    }
	}
	for (ctrl_set_map::iterator iter = set_ctrls.begin(); iter != set_ctrls.end(); ++iter) {
	    if (ctrl_str2id.find(iter->first) == ctrl_str2id.end()) {
		fprintf(stderr, "unknown control '%s'\n", iter->first.c_str());
		exit(1);
	    }
	}


	/* Information Opts */


	if (options[OptSetCtrl] && !set_ctrls.empty()) {
		struct v4l2_ext_controls ctrls = { 0 };

		for (ctrl_set_map::iterator iter = set_ctrls.begin();
				iter != set_ctrls.end(); ++iter) {
			struct v4l2_ext_control ctrl = { 0 };

			ctrl.id = ctrl_str2id[iter->first];
			ctrl.value = strtol(iter->second.c_str(), NULL, 0);
			if (V4L2_CTRL_ID2CLASS(ctrl.id) == V4L2_CTRL_CLASS_MPEG)
				mpeg_ctrls.push_back(ctrl);
			else
				user_ctrls.push_back(ctrl);
		}
		for (unsigned i = 0; i < user_ctrls.size(); i++) {
			struct v4l2_control ctrl;

			ctrl.id = user_ctrls[i].id;
			ctrl.value = user_ctrls[i].value;
			if (doioctl(fd, VIDIOC_S_CTRL, &ctrl, "VIDIOC_S_CTRL")) {
				fprintf(stderr, "%s: %s\n",
					ctrl_id2str[ctrl.id].c_str(),
					strerror(errno));
			}
		}
		if (mpeg_ctrls.size()) {
			ctrls.ctrl_class = V4L2_CTRL_CLASS_MPEG;
			ctrls.count = mpeg_ctrls.size();
			ctrls.controls = &mpeg_ctrls[0];
			if (doioctl(fd, VIDIOC_S_EXT_CTRLS, &ctrls, "VIDIOC_S_EXT_CTRLS")) {
				if (ctrls.error_idx >= ctrls.count) {
					fprintf(stderr, "Error setting MPEG controls: %s\n",
						strerror(errno));
				}
				else {
					fprintf(stderr, "%s: %s\n",
						ctrl_id2str[mpeg_ctrls[ctrls.error_idx].id].c_str(),
						strerror(errno));
				}
			}
		}
	}

	/* Get options */

	if (options[OptGetCtrl] && !get_ctrls.empty()) {
		struct v4l2_ext_controls ctrls = { 0 };

		mpeg_ctrls.clear();
		user_ctrls.clear();
		for (ctrl_get_list::iterator iter = get_ctrls.begin();
				iter != get_ctrls.end(); ++iter) {
			struct v4l2_ext_control ctrl = { 0 };

			ctrl.id = ctrl_str2id[*iter];
			if (V4L2_CTRL_ID2CLASS(ctrl.id) == V4L2_CTRL_CLASS_MPEG)
				mpeg_ctrls.push_back(ctrl);
			else
				user_ctrls.push_back(ctrl);
		}
		for (unsigned i = 0; i < user_ctrls.size(); i++) {
			struct v4l2_control ctrl;

			ctrl.id = user_ctrls[i].id;
			doioctl(fd, VIDIOC_G_CTRL, &ctrl, "VIDIOC_G_CTRL");
			printf("%s: %d\n", ctrl_id2str[ctrl.id].c_str(), ctrl.value);
		}
		if (mpeg_ctrls.size()) {
			ctrls.ctrl_class = V4L2_CTRL_CLASS_MPEG;
			ctrls.count = mpeg_ctrls.size();
			ctrls.controls = &mpeg_ctrls[0];
			doioctl(fd, VIDIOC_G_EXT_CTRLS, &ctrls, "VIDIOC_G_EXT_CTRLS");
			for (unsigned i = 0; i < mpeg_ctrls.size(); i++) {
				struct v4l2_ext_control ctrl = mpeg_ctrls[i];

				printf("%s: %d\n", ctrl_id2str[ctrl.id].c_str(), ctrl.value);
			}
		}
	}
	if (options[OptListCtrlsMenus]) {
		list_controls(fd, 1);
	}

	if (options[OptListCtrls]) {
		list_controls(fd, 0);
	}


	close(fd);
	exit(app_result);
}
void common_set(int fd)
{
	if (options[OptSetPriority]) {
		if (doioctl(fd, VIDIOC_S_PRIORITY, &prio) >= 0) {
			printf("Priority set: %d\n", prio);
		}
	}

	if (options[OptSetCtrl] && !set_ctrls.empty()) {
		struct v4l2_ext_controls ctrls;
		class2ctrls_map class2ctrls;
		bool use_ext_ctrls = false;

		memset(&ctrls, 0, sizeof(ctrls));
		for (ctrl_set_map::iterator iter = set_ctrls.begin();
				iter != set_ctrls.end(); ++iter) {
			struct v4l2_ext_control ctrl;
			struct v4l2_query_ext_ctrl &qc = ctrl_str2q[iter->first];

			memset(&ctrl, 0, sizeof(ctrl));
			ctrl.id = qc.id;
			if (qc.type == V4L2_CTRL_TYPE_INTEGER64)
				use_ext_ctrls = true;
			if (qc.flags & V4L2_CTRL_FLAG_HAS_PAYLOAD) {
				struct v4l2_ext_controls ctrls = { 0, 1 };
				unsigned divide[V4L2_CTRL_MAX_DIMS] = { 0 };
				ctrl_subset subset;
				long long v;
				unsigned d, i;

				use_ext_ctrls = true;
				ctrl.size = qc.elems * qc.elem_size;
				ctrl.ptr = malloc(ctrl.size);

				ctrls.controls = &ctrl;
				ioctl(fd, VIDIOC_G_EXT_CTRLS, &ctrls);

				if (fill_subset(qc, subset))
					return;

				divide[qc.nr_of_dims - 1] = 1;
				for (d = 0; d < qc.nr_of_dims - 1; d++) {
					divide[d] = qc.dims[d + 1];
					for (i = 0; i < d; i++)
						divide[i] *= divide[d];
				}


				switch (qc.type) {
				case V4L2_CTRL_TYPE_U8:
					v = strtoul(iter->second.c_str(), NULL, 0);
					for (i = 0; i < qc.elems; i++)
						if (idx_in_subset(qc, subset, divide, i))
							ctrl.p_u8[i] = v;
					break;
				case V4L2_CTRL_TYPE_U16:
					v = strtoul(iter->second.c_str(), NULL, 0);
					for (i = 0; i < qc.elems; i++)
						if (idx_in_subset(qc, subset, divide, i))
							ctrl.p_u16[i] = v;
					break;
				case V4L2_CTRL_TYPE_U32:
					v = strtoul(iter->second.c_str(), NULL, 0);
					for (i = 0; i < qc.elems; i++)
						if (idx_in_subset(qc, subset, divide, i))
							ctrl.p_u32[i] = v;
					break;
				case V4L2_CTRL_TYPE_STRING:
					strncpy(ctrl.string, iter->second.c_str(), qc.maximum);
					ctrl.string[qc.maximum] = 0;
					break;
				default:
					fprintf(stderr, "%s: unsupported payload type\n",
							qc.name);
					break;
				}
			} else {
				if (V4L2_CTRL_DRIVER_PRIV(ctrl.id))
					use_ext_ctrls = true;
				ctrl.value = strtol(iter->second.c_str(), NULL, 0);
			}
			class2ctrls[V4L2_CTRL_ID2CLASS(ctrl.id)].push_back(ctrl);
		}
		for (class2ctrls_map::iterator iter = class2ctrls.begin();
				iter != class2ctrls.end(); ++iter) {
			if (!use_ext_ctrls &&
			    (iter->first == V4L2_CTRL_CLASS_USER ||
			     iter->first == V4L2_CID_PRIVATE_BASE)) {
				for (unsigned i = 0; i < iter->second.size(); i++) {
					struct v4l2_control ctrl;

					ctrl.id = iter->second[i].id;
					ctrl.value = iter->second[i].value;
					if (doioctl(fd, VIDIOC_S_CTRL, &ctrl)) {
						fprintf(stderr, "%s: %s\n",
								ctrl_id2str[ctrl.id].c_str(),
								strerror(errno));
					}
				}
				continue;
			}
			if (iter->second.size()) {
				ctrls.ctrl_class = iter->first;
				ctrls.count = iter->second.size();
				ctrls.controls = &iter->second[0];
				if (doioctl(fd, VIDIOC_S_EXT_CTRLS, &ctrls)) {
					if (ctrls.error_idx >= ctrls.count) {
						fprintf(stderr, "Error setting controls: %s\n",
								strerror(errno));
					}
					else {
						fprintf(stderr, "%s: %s\n",
								ctrl_id2str[iter->second[ctrls.error_idx].id].c_str(),
								strerror(errno));
					}
				}
			}
		}
	}
}
void common_set(int fd)
{
	if (options[OptSetPriority]) {
		if (doioctl(fd, VIDIOC_S_PRIORITY, &prio) >= 0) {
			printf("Priority set: %d\n", prio);
		}
	}

	if (options[OptSetCtrl] && !set_ctrls.empty()) {
		struct v4l2_ext_controls ctrls;
		class2ctrls_map class2ctrls;
		bool use_ext_ctrls = false;

		memset(&ctrls, 0, sizeof(ctrls));
		for (ctrl_set_map::iterator iter = set_ctrls.begin();
				iter != set_ctrls.end(); ++iter) {
			struct v4l2_ext_control ctrl;

			memset(&ctrl, 0, sizeof(ctrl));
			ctrl.id = ctrl_str2q[iter->first].id;
			if (ctrl_str2q[iter->first].type == V4L2_CTRL_TYPE_INTEGER64)
				use_ext_ctrls = true;
			if (ctrl_str2q[iter->first].type == V4L2_CTRL_TYPE_STRING) {
				unsigned len = iter->second.length();
				unsigned maxlen = ctrl_str2q[iter->first].maximum;

				use_ext_ctrls = true;
				ctrl.size = maxlen + 1;
				ctrl.string = (char *)malloc(ctrl.size);
				if (len > maxlen) {
					memcpy(ctrl.string, iter->second.c_str(), maxlen);
					ctrl.string[maxlen] = 0;
				}
				else {
					strcpy(ctrl.string, iter->second.c_str());
				}
			} else {
				if (V4L2_CTRL_DRIVER_PRIV(ctrl.id))
					use_ext_ctrls = true;
				ctrl.value = strtol(iter->second.c_str(), NULL, 0);
			}
			class2ctrls[V4L2_CTRL_ID2CLASS(ctrl.id)].push_back(ctrl);
		}
		for (class2ctrls_map::iterator iter = class2ctrls.begin();
				iter != class2ctrls.end(); ++iter) {
			if (!use_ext_ctrls &&
			    (iter->first == V4L2_CTRL_CLASS_USER ||
			     iter->first == V4L2_CID_PRIVATE_BASE)) {
				for (unsigned i = 0; i < iter->second.size(); i++) {
					struct v4l2_control ctrl;

					ctrl.id = iter->second[i].id;
					ctrl.value = iter->second[i].value;
					if (doioctl(fd, VIDIOC_S_CTRL, &ctrl)) {
						fprintf(stderr, "%s: %s\n",
								ctrl_id2str[ctrl.id].c_str(),
								strerror(errno));
					}
				}
				continue;
			}
			if (iter->second.size()) {
				ctrls.ctrl_class = iter->first;
				ctrls.count = iter->second.size();
				ctrls.controls = &iter->second[0];
				if (doioctl(fd, VIDIOC_S_EXT_CTRLS, &ctrls)) {
					if (ctrls.error_idx >= ctrls.count) {
						fprintf(stderr, "Error setting MPEG controls: %s\n",
								strerror(errno));
					}
					else {
						fprintf(stderr, "%s: %s\n",
								ctrl_id2str[iter->second[ctrls.error_idx].id].c_str(),
								strerror(errno));
					}
				}
			}
		}
	}
}