text: /* Spa V4l2 Source
   *
   * Copyright © 2018 Wim Taymans
   *
   * Permission is hereby granted, free of charge, to any person obtaining a
   * copy of this software and associated documentation files (the "Software"),
   * to deal in the Software without restriction, including without limitation
   * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   * and/or sell copies of the Software, and to permit persons to whom the
   * Software is furnished to do so, subject to the following conditions:
   *
   * The above copyright notice and this permission notice (including the next
   * paragraph) shall be included in all copies or substantial portions of the
   * Software.
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
   * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
   * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
   * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
   * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
   * DEALINGS IN THE SOFTWARE.
   */
  
  #include <stddef.h>
  #include <sys/types.h>
  #include <sys/stat.h>
  #include <fcntl.h>
  
  #include <linux/videodev2.h>
  
  #include <spa/support/plugin.h>
  #include <spa/support/log.h>
  #include <spa/support/loop.h>
  #include <spa/utils/keys.h>
  #include <spa/utils/names.h>
  #include <spa/node/node.h>
  #include <spa/pod/builder.h>
  #include <spa/monitor/device.h>
  #include <spa/monitor/utils.h>
  #include <spa/debug/pod.h>
  
  #include "v4l2.h"
  
  #define NAME "v4l2-device"
  
  static const char default_device[] = "/dev/video0";
  
  struct props {
  	char device[64];
  	char device_name[128];
  	int device_fd;
  };
  
  static void reset_props(struct props *props)
  {
  	strncpy(props->device, default_device, 64);
  }
  
  struct impl {
  	struct spa_handle handle;
  	struct spa_device device;
  
  	struct spa_log *log;
  
  	struct props props;
  
  	struct spa_hook_list hooks;
  
  	struct spa_v4l2_device dev;
  };
  
  static int emit_info(struct impl *this, bool full)
  {
  	int res;
  	struct spa_dict_item items[10];
  	uint32_t n_items = 0;
  	struct spa_device_info info;
  	struct spa_param_info params[2];
          char path[128], version[16], capabilities[16], device_caps[16];
  
  	if ((res = spa_v4l2_open(&this->dev, this->props.device)) < 0)
  		return res;
  
  	info = SPA_DEVICE_INFO_INIT();
  
  	info.change_mask = SPA_DEVICE_CHANGE_MASK_PROPS;
  
  #define ADD_ITEM(key, value) items[n_items++] = SPA_DICT_ITEM_INIT(key, value)
  	snprintf(path, sizeof(path), "v4l2:%s", this->props.device);
  	ADD_ITEM(SPA_KEY_OBJECT_PATH, path);
  	ADD_ITEM(SPA_KEY_DEVICE_API, "v4l2");
  	ADD_ITEM(SPA_KEY_MEDIA_CLASS, "Video/Device");
  	ADD_ITEM(SPA_KEY_API_V4L2_PATH, (char *)this->props.device);
  	ADD_ITEM(SPA_KEY_API_V4L2_CAP_DRIVER, (char *)this->dev.cap.driver);
  	ADD_ITEM(SPA_KEY_API_V4L2_CAP_CARD, (char *)this->dev.cap.card);
  	ADD_ITEM(SPA_KEY_API_V4L2_CAP_BUS_INFO, (char *)this->dev.cap.bus_info);
  	snprintf(version, sizeof(version), "%u.%u.%u",
  			(this->dev.cap.version >> 16) & 0xFF,
  			(this->dev.cap.version >> 8) & 0xFF,
  			(this->dev.cap.version) & 0xFF);
  	ADD_ITEM(SPA_KEY_API_V4L2_CAP_VERSION, version);
  	snprintf(capabilities, sizeof(capabilities), "%08x", this->dev.cap.capabilities);
  	ADD_ITEM(SPA_KEY_API_V4L2_CAP_CAPABILITIES, capabilities);
  	snprintf(device_caps, sizeof(device_caps), "%08x", this->dev.cap.device_caps);
  	ADD_ITEM(SPA_KEY_API_V4L2_CAP_DEVICE_CAPS, device_caps);
  #undef ADD_ITEM
  	info.props = &SPA_DICT_INIT(items, n_items);
  
  	info.change_mask |= SPA_DEVICE_CHANGE_MASK_PARAMS;
  	params[0] = SPA_PARAM_INFO(SPA_PARAM_EnumProfile, SPA_PARAM_INFO_READ);
  	params[1] = SPA_PARAM_INFO(SPA_PARAM_Profile, SPA_PARAM_INFO_WRITE);
  	info.n_params = SPA_N_ELEMENTS(params);
  	info.params = params;
  
  	spa_device_emit_info(&this->hooks, &info);
  
  	if (spa_v4l2_is_capture(&this->dev)) {
  		struct spa_device_object_info oinfo;
  
  		oinfo = SPA_DEVICE_OBJECT_INFO_INIT();
  		oinfo.type = SPA_TYPE_INTERFACE_Node;
  		oinfo.factory_name = SPA_NAME_API_V4L2_SOURCE;
  		oinfo.change_mask = SPA_DEVICE_OBJECT_CHANGE_MASK_PROPS;
  		oinfo.props = &SPA_DICT_INIT(items, n_items);
  
  		spa_device_emit_object_info(&this->hooks, 0, &oinfo);
  	}
  
  	spa_v4l2_close(&this->dev);
  
  	return 0;
  }
  
  static int impl_add_listener(void *object,
  			struct spa_hook *listener,
  			const struct spa_device_events *events,
  			void *data)
  {
  	struct impl *this = object;
  	struct spa_hook_list save;
  	int res = 0;
  
  	spa_return_val_if_fail(this != NULL, -EINVAL);
  	spa_return_val_if_fail(events != NULL, -EINVAL);
  
  	spa_hook_list_isolate(&this->hooks, &save, listener, events, data);
  
  	if (events->info || events->object_info)
  		res = emit_info(this, true);
  
  	spa_hook_list_join(&this->hooks, &save);
  
  	return res;
  }
  
  static int impl_sync(void *object, int seq)
  {
  	struct impl *this = object;
  
  	spa_return_val_if_fail(this != NULL, -EINVAL);
  
  	spa_device_emit_result(&this->hooks, seq, 0, 0, NULL);
  
  	return 0;
  }
  
  static int impl_enum_params(void *object, int seq,
  			    uint32_t id, uint32_t start, uint32_t num,
  			    const struct spa_pod *filter)
  {
  	return -ENOTSUP;
  }
  
  static int impl_set_param(void *object,
  			  uint32_t id, uint32_t flags,
  			  const struct spa_pod *param)
  {
  	return -ENOTSUP;
  }
  
  static const struct spa_device_methods impl_device = {
  	SPA_VERSION_DEVICE_METHODS,
  	.add_listener = impl_add_listener,
  	.sync = impl_sync,
  	.enum_params = impl_enum_params,
  	.set_param = impl_set_param,
  };
  
  static int impl_get_interface(struct spa_handle *handle, const char *type, void **interface)
  {
  	struct impl *this;
  
  	spa_return_val_if_fail(handle != NULL, -EINVAL);
  	spa_return_val_if_fail(interface != NULL, -EINVAL);
  
  	this = (struct impl *) handle;
  
  	if (strcmp(type, SPA_TYPE_INTERFACE_Device) == 0)
  		*interface = &this->device;
  	else
  		return -ENOENT;
  
  	return 0;
  }
  
  static int impl_clear(struct spa_handle *handle)
  {
  	return 0;
  }
  
  static size_t
  impl_get_size(const struct spa_handle_factory *factory,
  	      const struct spa_dict *params)
  {
  	return sizeof(struct impl);
  }
  
  static int
  impl_init(const struct spa_handle_factory *factory,
  	  struct spa_handle *handle,
  	  const struct spa_dict *info,
  	  const struct spa_support *support,
  	  uint32_t n_support)
  {
  	struct impl *this;
  	const char *str;
  
  	spa_return_val_if_fail(factory != NULL, -EINVAL);
  	spa_return_val_if_fail(handle != NULL, -EINVAL);
  
  	handle->get_interface = impl_get_interface;
  	handle->clear = impl_clear, this = (struct impl *) handle;
  
  	this->log = spa_support_find(support, n_support, SPA_TYPE_INTERFACE_Log);
  
  	spa_hook_list_init(&this->hooks);
  
  	this->device.iface = SPA_INTERFACE_INIT(
  			SPA_TYPE_INTERFACE_Device,
  			SPA_VERSION_DEVICE,
  			&impl_device, this);
  	this->dev.log = this->log;
  	this->dev.fd = -1;
  
  	reset_props(&this->props);
  
  	if (info && (str = spa_dict_lookup(info, SPA_KEY_API_V4L2_PATH)))
  		strncpy(this->props.device, str, 63);
  
  	return 0;
  }
  
  static const struct spa_interface_info impl_interfaces[] = {
  	{SPA_TYPE_INTERFACE_Device,},
  };
  
  static int impl_enum_interface_info(const struct spa_handle_factory *factory,
  				    const struct spa_interface_info **info,
  				    uint32_t *index)
  {
  	spa_return_val_if_fail(factory != NULL, -EINVAL);
  	spa_return_val_if_fail(info != NULL, -EINVAL);
  	spa_return_val_if_fail(index != NULL, -EINVAL);
  
  	if (*index >= SPA_N_ELEMENTS(impl_interfaces))
  		return 0;
  
  	*info = &impl_interfaces[(*index)++];
  
  	return 1;
  }
  
  const struct spa_handle_factory spa_v4l2_device_factory = {
  	SPA_VERSION_HANDLE_FACTORY,
  	SPA_NAME_API_V4L2_DEVICE,
  	NULL,
  	impl_get_size,
  	impl_init,
  	impl_enum_interface_info,
  };
  