plugins: refactor, break out inotify watcher to src/iwatch.[ch]

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

src/Makefile.am

@@ -26,6 +26,7 @@ finit_SOURCES      = api.c	cgroup.c	cgroup.h	\
 		     exec.c	finit.c		finit.h		\
 		     getty.c	stty.c				\
 		     helpers.c	helpers.h			\
+		     iwatch.c   iwatch.h			\
 		     log.c	log.h				\
 		     mdadm.c	mount.c				\
 		     pid.c      pid.h				\

src/iwatch.c

@@ -0,0 +1,118 @@
+#include <errno.h>
+
+#include "finit.h"
+#include "iwatch.h"
+#include "log.h"
+
+
+int iwatch_init(struct iwatch *iw)
+{
+	if (!iw) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	TAILQ_INIT(&iw->iwp_list);
+
+	iw->fd = inotify_init1(IN_NONBLOCK | IN_CLOEXEC);
+	if (iw->fd < 0) {
+		_pe("inotify_init()");
+		return -1;
+	}
+
+	return iw->fd;
+}
+
+void iwatch_exit(struct iwatch *iw)
+{
+	struct iwatch_path *iwp, *tmp;
+
+	TAILQ_FOREACH_SAFE(iwp, &iw->iwp_list, link, tmp) {
+		TAILQ_REMOVE(&iw->iwp_list, iwp, link);
+		inotify_rm_watch(iw->fd, iwp->wd);
+		free(iwp->path);
+		free(iwp);
+	}
+
+	close(iw->fd);
+}
+
+int iwatch_add(struct iwatch *iw, char *file, uint32_t mask)
+{
+	struct iwatch_path *iwp;
+	char *path;
+	int wd;
+
+	_d("Adding new watcher for path %s", file);
+
+	path = strdup(file);
+	if (!path) {
+		_pe("Out of memory");
+		return -1;
+	}
+
+	wd = inotify_add_watch(iw->fd, path, IWATCH_MASK | mask);
+	if (wd < 0) {
+		_pe("inotify_add_watch(%s)", path);
+		free(path);
+		return -1;
+	}
+
+	iwp = malloc(sizeof(struct iwatch_path));
+	if (!iwp) {
+		_pe("Failed allocating new `struct iwatch_path`");
+		inotify_rm_watch(iw->fd, wd);
+		free(path);
+		return -1;
+	}
+
+	iwp->path = path;
+	iwp->wd = wd;
+	TAILQ_INSERT_HEAD(&iw->iwp_list, iwp, link);
+
+	return 0;
+}
+
+int iwatch_del(struct iwatch *iw, struct iwatch_path *iwp)
+{
+	_d("Removing watcher for removed path %s", iwp->path);
+
+	TAILQ_REMOVE(&iw->iwp_list, iwp, link);
+	inotify_rm_watch(iw->fd, iwp->wd);
+	free(iwp->path);
+	free(iwp);
+
+	return 0;
+}
+
+struct iwatch_path *iwatch_find_by_wd(struct iwatch *iw, int wd)
+{
+	struct iwatch_path *iwp;
+
+	TAILQ_FOREACH(iwp, &iw->iwp_list, link) {
+		if (iwp->wd == wd)
+			return iwp;
+	}
+
+	return NULL;
+}
+
+struct iwatch_path *iwatch_find_by_path(struct iwatch *iw, const char *path)
+{
+	struct iwatch_path *iwp;
+
+	TAILQ_FOREACH(iwp, &iw->iwp_list, link) {
+		if (!strcmp(iwp->path, path))
+			return iwp;
+	}
+
+	return NULL;
+}
+
+/**
+ * Local Variables:
+ *  indent-tabs-mode: t
+ *  c-file-style: "linux"
+ * End:
+ */
+

src/iwatch.h

@@ -0,0 +1,64 @@
+/* inotify watcher for files or directories
+ *
+ * Copyright (c) 2015-2016  Tobias Waldekranz <tobias@waldekranz.com>
+ * Copyright (c) 2016-2021  Joachim Wiberg <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_IWATCH_H_
+#define FINIT_IWATCH_H_
+
+#include <stdint.h>
+#include <lite/queue.h>
+#include <sys/inotify.h>
+
+
+/* Monitors changes to both directories and files by default */
+#define IWATCH_MASK (IN_CREATE | IN_DELETE | IN_MODIFY | IN_ATTRIB | IN_MOVE)
+
+struct iwatch_path {
+	TAILQ_ENTRY(iwatch_path) link;
+	char *path;
+	int wd;
+};
+
+struct iwatch {
+	int fd;
+	TAILQ_HEAD(, iwatch_path) iwp_list;
+};
+
+
+int  iwatch_init (struct iwatch *iw);
+void iwatch_exit (struct iwatch *iw);
+
+int  iwatch_add  (struct iwatch *iw, char *file, uint32_t mask);
+int  iwatch_del  (struct iwatch *iw, struct iwatch_path *iwp);
+
+struct iwatch_path *iwatch_find_by_wd   (struct iwatch *iw, int wd);
+struct iwatch_path *iwatch_find_by_path (struct iwatch *iw, const char *path);
+
+#endif /* FINIT_IWATCH_H_ */
+
+/**
+ * Local Variables:
+ *  indent-tabs-mode: t
+ *  c-file-style: "linux"
+ * End:
+ */