Merge branch 'autoreload'

Pull request #278.

Fixes issue #29 and issue #199.

1 files changed, 113 insertions, 0 deletions

diff --git a/autoreload_inotify.c b/autoreload_inotify.c
new file mode 100644
index 0000000..fe05483
--- /dev/null
+++ b/autoreload_inotify.c
@@ -0,0 +1,113 @@
+/* Copyright 2017 Max Voit
+ *
+ * This file is part of sxiv.
+ *
+ * sxiv is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published
+ * by the Free Software Foundation; either version 2 of the License,
+ * or (at your option) any later version.
+ *
+ * sxiv 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with sxiv.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <errno.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/inotify.h>
+
+#include "util.h"
+#include "autoreload.h"
+
+void arl_init(arl_t *arl)
+{
+	arl->fd = inotify_init1(IN_CLOEXEC | IN_NONBLOCK);
+	arl->wd_dir = arl->wd_file = -1;
+	if (arl->fd == -1)
+		error(0, 0, "Could not initialize inotify, no automatic image reloading");
+}
+
+CLEANUP void arl_cleanup(arl_t *arl)
+{
+	if (arl->fd != -1)
+		close(arl->fd);
+	free(arl->filename);
+}
+
+static void rm_watch(int fd, int *wd)
+{
+	if (*wd != -1) {
+		inotify_rm_watch(fd, *wd);
+		*wd = -1;
+	}
+}
+
+static void add_watch(int fd, int *wd, const char *path, uint32_t mask)
+{
+	*wd = inotify_add_watch(fd, path, mask);
+	if (*wd == -1)
+		error(0, errno, "inotify: %s", path);
+}
+
+void arl_setup(arl_t *arl, const char *filepath)
+{
+	char *base = strrchr(filepath, '/');
+
+	if (arl->fd == -1)
+		return;
+
+	rm_watch(arl->fd, &arl->wd_dir);
+	rm_watch(arl->fd, &arl->wd_file);
+
+	add_watch(arl->fd, &arl->wd_file, filepath, IN_CLOSE_WRITE | IN_DELETE_SELF);
+
+	free(arl->filename);
+	arl->filename = estrdup(filepath);
+
+	if (base != NULL) {
+		arl->filename[++base - filepath] = '\0';
+		add_watch(arl->fd, &arl->wd_dir, arl->filename, IN_CREATE | IN_MOVED_TO);
+		strcpy(arl->filename, base);
+	}
+}
+
+union {
+	char d[4096]; /* aligned buffer */
+	struct inotify_event e;
+} buf;
+
+bool arl_handle(arl_t *arl)
+{
+	bool reload = false;
+	char *ptr;
+	const struct inotify_event *event;
+
+	for (;;) {
+		ssize_t len = read(arl->fd, buf.d, sizeof(buf.d));
+
+		if (len == -1) {
+			if (errno == EINTR)
+				continue;
+			break;
+		}
+		for (ptr = buf.d; ptr < buf.d + len; ptr += sizeof(*event) + event->len) {
+			event = (const struct inotify_event*) ptr;
+			if (event->mask & IN_CLOSE_WRITE) {
+				reload = true;
+			} else if (event->mask & IN_DELETE_SELF) {
+				rm_watch(arl->fd, &arl->wd_file);
+			} else if (event->mask & (IN_CREATE | IN_MOVED_TO)) {
+				if (STREQ(event->name, arl->filename))
+					reload = true;
+			}
+		}
+	}
+	return reload;
+}
+