schedule: Add simple work queue helper

Signed-off-by: Joachim Nilsson <troglobit@gmail.com>

src/Makefile.am

@@ -28,6 +28,7 @@ finit_SOURCES      = api.c					\
 		     mdadm.c	mount.c				\
 		     pid.c      pid.h				\
 		     plugin.c	plugin.h	private.h	\
+		     schedule.c	schedule.h			\
 		     service.c	service.h			\
 		     sig.c	sig.h				\
 		     sm.c	sm.h				\

src/schedule.c

@@ -0,0 +1,69 @@
+/* Work queue helper functions
+ *
+ * Copyright (c) 2018  Joachim Nilsson <troglobit@gmail.com>
+ *
+ * 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 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 "config.h"
+#include "finit.h"
+#include "schedule.h"
+
+#define SC_INIT 0x494E4954	/* "INIT", see ascii(7) */
+
+/*
+ * libuEv callback wrapper
+ */
+static void cb(uev_t *w, void *arg, int events)
+{
+	struct wq *work = (struct wq *)arg;
+
+	if (UEV_ERROR == events) {
+		uev_timer_start(w);
+		return;
+	}
+
+	work->cb(work);
+}
+
+/*
+ * Place work on event queue
+ */
+int schedule_work(struct wq *work)
+{
+	int msec;
+
+	if (!work)
+		return errno = EINVAL;
+
+	msec = work->delay;
+	if (work->init != SC_INIT) {
+		work->init = SC_INIT;
+		return uev_timer_init(ctx, &work->watcher, cb, work, msec, 0);
+	}
+
+	return uev_timer_set(&work->watcher, msec, 0);
+}
+
+/**
+ * Local Variables:
+ *  indent-tabs-mode: t
+ *  c-file-style: "linux"
+ * End:
+ */

src/schedule.h

@@ -0,0 +1,37 @@
+/* Work queue helper functions
+ *
+ * Copyright (c) 2018  Joachim Nilsson <troglobit@gmail.com>
+ *
+ * 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 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.
+ */
+
+#ifndef FINIT_SCHEDULE_H_
+#define FINIT_SCHEDULE_H_
+
+struct wq {
+	uev_t   watcher;
+	int     init;
+	int     delay;		/* msec delay before starting work */
+	void  (*cb)(void *);
+	void   *arg;
+};
+
+int   schedule_work(struct wq *work);
+
+#endif /* FINIT_SCHEDULE_H_ */