rename signal -> sig

Meson puts the directory of the source file in the include path and then
it picks up our signal.h instead of the system one...

pinos/client/sig.h

@@ -0,0 +1,70 @@
+/* Pinos
+ * Copyright (C) 2015 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.
+ */
+
+#ifndef __PINOS_SIGNAL_H__
+#define __PINOS_SIGNAL_H__
+
+#include <spa/include/spa/list.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef struct _PinosSignal PinosSignal;
+typedef struct _PinosListener PinosListener;
+
+struct _PinosListener {
+  SpaList         link;
+  void (*notify) (void *);
+};
+
+#define PINOS_SIGNAL(name,func)                                         \
+  union {                                                               \
+    SpaList listeners;                                                  \
+    void (*notify) func;                                                \
+  } name;
+
+#define pinos_signal_init(signal)                                       \
+  spa_list_init (&(signal)->listeners);
+
+#define pinos_signal_add(signal,listener,func)                          \
+  do {                                                                  \
+    __typeof__((signal)->notify) n = (func);                            \
+    (listener)->notify = (void (*) (void *)) n;                         \
+    spa_list_insert ((signal)->listeners.prev, &(listener)->link);      \
+  } while (false);
+
+static inline void
+pinos_signal_remove (PinosListener *listener)
+{
+  spa_list_remove (&listener->link);
+}
+
+#define pinos_signal_emit(signal,...)                                   \
+  do {                                                                  \
+    PinosListener *l, *next;                                            \
+    spa_list_for_each_safe (l, next, &(signal)->listeners, link)        \
+      ((__typeof__((signal)->notify))l->notify) (l,__VA_ARGS__);        \
+  } while (false);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __PINOS_SIGNAL_H__ */