Refactor TTY code to honor runlevels and use I/O plugin to watch /dev

Add support for runlevels to tty command and support for reading baud
rate and TERM variable from finit.conf.

The tty-watcher thread has been converted to a standard I/O plugin.

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

plugins/Makefile

@@ -4,7 +4,7 @@ CPPFLAGS   += -I..
 LDFLAGS    := $(filter-out -rdynamic, $(LDFLAGS))
 LDFLAGS    += -shared
 PLUGINS    ?= initctl.so alsa-utils.so bootmisc.so dbus.so hwclock.so \
-	      resolvconf.so urandom.so x11-common.so
+	      resolvconf.so urandom.so x11-common.so tty.so
 DEPS        = $(addprefix .,$(PLUGINS:.so=.d))
 
 include ../common.mk

plugins/tty.c

@@ -0,0 +1,94 @@
+/* Optional TTY Watcher, used to catch new TTYs that are discovered, e.g., USB
+ *
+ * Copyright (c) 2013  Mattias Walström <lazzer@gmail.com>
+ * Copyright (c) 2013  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 <errno.h>
+#include <fcntl.h>		/* O_RDONLY et al */
+#include <unistd.h>		/* read() */
+#include <sys/inotify.h>
+#include <sys/stat.h>
+
+#include "finit.h"
+#include "helpers.h"
+#include "plugin.h"
+#include "tty.h"
+
+static void watcher(void *arg, int fd, int events);
+
+static plugin_t plugin = {
+	.io = {
+		.cb    = watcher,
+		.flags = PLUGIN_IO_READ,
+	},
+};
+
+static void setup(void)
+{
+	plugin.io.fd = inotify_init1(IN_NONBLOCK);
+	if (-1 == plugin.io.fd || inotify_add_watch(plugin.io.fd, "/dev", IN_CREATE | IN_DELETE) < 0)
+		_e("Failed starting TTY watcher: %s", strerror(errno));
+}
+
+static void watcher(void *UNUSED(arg), int fd, int UNUSED(events))
+{
+	int len = 0;
+	char buf[EVENT_SIZE], name[42];
+	tty_node_t *entry;
+	struct inotify_event *notified = (struct inotify_event *)buf;
+
+	while ((len = read(fd, buf, sizeof(buf)))) {
+		if (-1 == len) {
+			if (errno == EINTR)
+				continue;
+			break;
+		}
+
+		snprintf(name, sizeof(name), "/dev/%s", notified->name);
+		entry = tty_find(name);
+		if (entry && tty_enabled(&entry->data, runlevel)) {
+			if (notified->mask & IN_CREATE)
+				tty_start(&entry->data);
+			else if (entry->data.pid)
+				tty_stop(&entry->data);
+		}
+	}
+}
+
+PLUGIN_INIT(plugin_init)
+{
+	setup();
+	plugin_register(&plugin);
+}
+
+PLUGIN_EXIT(plugin_exit)
+{
+	plugin_unregister(&plugin);
+}
+
+/**
+ * Local Variables:
+ *  version-control: t
+ *  indent-tabs-mode: t
+ *  c-file-style: "linux"
+ * End:
+ */