device: add device object

Make a device object, let the v4l2 monitor create device objects
The device object is responsible for dynamically creating nodes.

src/modules/spa/spa-device.c

@@ -0,0 +1,164 @@
+/* PipeWire
+ *
+ * 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.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <string.h>
+#include <stdio.h>
+#include <dlfcn.h>
+
+#include <spa/param/props.h>
+#include <spa/pod/iter.h>
+#include <spa/debug/types.h>
+
+#include "spa-device.h"
+#include "pipewire/device.h"
+#include "pipewire/port.h"
+#include "pipewire/log.h"
+#include "pipewire/private.h"
+
+struct impl {
+	struct pw_device *this;
+
+	struct pw_client *owner;
+	struct pw_global *parent;
+
+	enum pw_spa_device_flags flags;
+
+	void *unload;
+        struct spa_handle *handle;
+        struct spa_device *device;
+	char *lib;
+	char *factory_name;
+
+	struct spa_hook device_listener;
+
+	void *user_data;
+};
+
+static void device_destroy(void *data)
+{
+	struct impl *impl = data;
+	struct pw_device *device = impl->this;
+
+	pw_log_debug("spa-device %p: free", device);
+
+	spa_hook_remove(&impl->device_listener);
+	if (impl->unload)
+		pw_unload_spa_interface(impl->unload);
+	if (impl->handle) {
+		spa_handle_clear(impl->handle);
+		free(impl->handle);
+	}
+	free(impl->lib);
+	free(impl->factory_name);
+}
+
+static const struct pw_device_events device_events = {
+	PW_VERSION_DEVICE_EVENTS,
+	.destroy = device_destroy,
+};
+
+struct pw_device *
+pw_spa_device_new(struct pw_core *core,
+		  struct pw_client *owner,
+		  struct pw_global *parent,
+		  const char *name,
+		  enum pw_spa_device_flags flags,
+		  struct spa_device *device,
+		  struct spa_handle *handle,
+		  struct pw_properties *properties,
+		  size_t user_data_size)
+{
+	struct pw_device *this;
+	struct impl *impl;
+
+	this = pw_device_new(core, name, properties, sizeof(struct impl) + user_data_size);
+	if (this == NULL)
+		return NULL;
+
+	impl = this->user_data;
+	impl->this = this;
+	impl->owner = owner;
+	impl->parent = parent;
+	impl->device = device;
+	impl->flags = flags;
+
+	if (user_data_size > 0)
+                impl->user_data = SPA_MEMBER(impl, sizeof(struct impl), void);
+
+	pw_device_add_listener(this, &impl->device_listener, &device_events, impl);
+
+	if (!SPA_FLAG_CHECK(impl->flags, PW_SPA_DEVICE_FLAG_NO_REGISTER))
+		pw_device_register(this, impl->owner, impl->parent, NULL);
+
+	pw_device_set_implementation(this, impl->device);
+
+	return this;
+}
+
+void *pw_spa_device_get_user_data(struct pw_device *device)
+{
+	struct impl *impl = device->user_data;
+	return impl->user_data;
+}
+
+struct pw_device *pw_spa_device_load(struct pw_core *core,
+				 struct pw_client *owner,
+				 struct pw_global *parent,
+				 const char *lib,
+				 const char *factory_name,
+				 const char *name,
+				 enum pw_spa_device_flags flags,
+				 struct pw_properties *properties,
+				 size_t user_data_size)
+{
+	struct pw_device *this;
+	struct impl *impl;
+	struct spa_device *device;
+	const struct spa_support *support;
+	uint32_t n_support;
+
+	support = pw_core_get_support(core, &n_support);
+
+	device = pw_load_spa_interface(lib, factory_name, SPA_TYPE_INTERFACE_Device,
+			properties ? &properties->dict : NULL, n_support, support);
+	if (device == NULL)
+		goto open_failed;
+
+	this = pw_spa_device_new(core, owner, parent, name, flags,
+			       device, NULL, properties, user_data_size);
+
+	impl = this->user_data;
+	impl->unload = device;
+	impl->lib = strdup(lib);
+	impl->factory_name = strdup(factory_name);
+
+	return this;
+
+      open_failed:
+	return NULL;
+}