node: remove node state

Remove the node state. The state of the node is based on the state
of the ports, which can be derived directly from calling the port
methods. Track this state in the Port instead.
Add a mixer module that puts a mixer in from of audio sinks. This allows
multiple clients to play on one sink (still has some bugs). do some
fixes in the mixer and the scheduler to make this work.

pinos/modules/module-mixer.c

@@ -0,0 +1,188 @@
+/* Pinos
+ * Copyright (C) 2017 Wim Taymans <wim.taymans@gmail.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
+ * Boston, MA 02110-1301, USA.
+ */
+
+#include <string.h>
+#include <stdio.h>
+#include <errno.h>
+#include <dlfcn.h>
+
+#include "config.h"
+
+#include "pinos/server/core.h"
+#include "pinos/server/module.h"
+
+#define AUDIOMIXER_LIB "build/spa/plugins/audiomixer/libspa-audiomixer.so"
+
+typedef struct {
+  PinosCore       *core;
+  PinosProperties *properties;
+
+  void *hnd;
+  const SpaHandleFactory *factory;
+
+  PinosListener  check_send;
+  PinosListener  check_dispatch;
+} ModuleImpl;
+
+static const SpaHandleFactory *
+find_factory (ModuleImpl *impl)
+{
+  SpaEnumHandleFactoryFunc enum_func;
+  uint32_t index;
+  const SpaHandleFactory *factory = NULL;
+  SpaResult res;
+
+  if ((impl->hnd = dlopen (AUDIOMIXER_LIB, RTLD_NOW)) == NULL) {
+    pinos_log_error ("can't load %s: %s", AUDIOMIXER_LIB, dlerror());
+    return NULL;
+  }
+  if ((enum_func = dlsym (impl->hnd, "spa_enum_handle_factory")) == NULL) {
+    pinos_log_error ("can't find enum function");
+    goto no_symbol;
+  }
+
+  for (index = 0; ; index++) {
+    if ((res = enum_func (&factory, index)) < 0) {
+      if (res != SPA_RESULT_ENUM_END)
+        pinos_log_error ("can't enumerate factories: %d", res);
+      goto enum_failed;
+    }
+    if (strcmp (factory->name, "audiomixer") == 0)
+      break;
+  }
+  return factory;
+
+enum_failed:
+no_symbol:
+  dlclose (impl->hnd);
+  impl->hnd = NULL;
+  return NULL;
+}
+
+static PinosNode *
+make_node (ModuleImpl *impl)
+{
+  SpaHandle *handle;
+  SpaResult res;
+  void *iface;
+  SpaNode *spa_node;
+  SpaClock *spa_clock;
+  PinosNode *node;
+
+  handle = calloc (1, impl->factory->size);
+  if ((res = spa_handle_factory_init (impl->factory,
+                                      handle,
+                                      NULL,
+                                      impl->core->support,
+                                      impl->core->n_support)) < 0) {
+    pinos_log_error ("can't make factory instance: %d", res);
+    goto init_failed;
+  }
+  if ((res = spa_handle_get_interface (handle,
+                                       impl->core->type.spa_node,
+                                       &iface)) < 0) {
+    pinos_log_error ("can't get interface %d", res);
+    goto interface_failed;
+  }
+  spa_node = iface;
+
+  if ((res = spa_handle_get_interface (handle,
+                                       impl->core->type.spa_clock,
+                                       &iface)) < 0) {
+    iface = NULL;
+  }
+  spa_clock = iface;
+
+  node = pinos_node_new (impl->core,
+                         "audiomixer",
+                         false,
+                         spa_node,
+                         spa_clock,
+                         NULL);
+  return node;
+
+interface_failed:
+  spa_handle_clear (handle);
+init_failed:
+  free (handle);
+  return NULL;
+}
+
+static ModuleImpl *
+module_new (PinosCore       *core,
+            PinosProperties *properties)
+{
+  ModuleImpl *impl;
+  PinosNode *n;
+
+  impl = calloc (1, sizeof (ModuleImpl));
+  pinos_log_debug ("module %p: new", impl);
+
+  impl->core = core;
+  impl->properties = properties;
+
+  impl->factory = find_factory (impl);
+
+  spa_list_for_each (n, &core->node_list, link) {
+    const char *str;
+    char *error;
+    PinosNode *node;
+    PinosPort *ip, *op;
+
+    if (n->global == NULL)
+      continue;
+
+    if (n->properties == NULL)
+      continue;
+
+    if ((str = pinos_properties_get (n->properties, "media.class")) == NULL)
+      continue;
+
+    if (strcmp (str, "Audio/Sink") != 0)
+      continue;
+
+    if ((ip = pinos_node_get_free_port (n, PINOS_DIRECTION_INPUT)) == NULL)
+      continue;
+
+    node = make_node (impl);
+    op = pinos_node_get_free_port (node, PINOS_DIRECTION_OUTPUT);
+    if (op == NULL)
+      continue;
+
+    pinos_port_link (op, ip, NULL, NULL, &error);
+  }
+  return impl;
+}
+
+#if 0
+static void
+module_destroy (ModuleImpl *impl)
+{
+  pinos_log_debug ("module %p: destroy", impl);
+
+  free (impl);
+}
+#endif
+
+bool
+pinos__module_init (PinosModule * module, const char * args)
+{
+  module_new (module->core, NULL);
+  return true;
+}