Merge branch 'autoreload'

Pull request #278.

Fixes issue #29 and issue #199.

5 files changed, 219 insertions, 3 deletions

diff --git a/Makefile b/Makefile
index f375fa3..8b3f4b5 100644
--- a/Makefile
+++ b/Makefile
@@ -21,9 +21,13 @@ ifndef NO_LIBEXIF
 	LIBS     += -lexif
 endif
 
+# select autoreload backend
+# overwritten with `make AUTORELOAD=nop`
+AUTORELOAD := inotify
+
 .PHONY: clean install uninstall
 
-SRC := commands.c image.c main.c options.c thumbs.c util.c window.c
+SRC := autoreload_$(AUTORELOAD).c commands.c image.c main.c options.c thumbs.c util.c window.c
 DEP := $(SRC:.c=.d)
 OBJ := $(SRC:.c=.o)
 
diff --git a/autoreload.h b/autoreload.h
new file mode 100644
index 0000000..bb30eb6
--- /dev/null
+++ b/autoreload.h
@@ -0,0 +1,36 @@
+/* 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/>.
+ */
+
+#ifndef AUTORELOAD_H
+#define AUTORELOAD_H
+
+#include "types.h"
+
+typedef struct {
+	int fd;
+	int wd_dir;
+	int wd_file;
+	char *filename;
+} arl_t;
+
+void arl_init(arl_t*);
+void arl_cleanup(arl_t*);
+void arl_setup(arl_t*, const char* /* result of realpath(3) */);
+bool arl_handle(arl_t*);
+
+#endif /* AUTORELOAD_H */
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;
+}
+
diff --git a/autoreload_nop.c b/autoreload_nop.c
new file mode 100644
index 0000000..41dbf47
--- /dev/null
+++ b/autoreload_nop.c
@@ -0,0 +1,43 @@
+/* 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 "autoreload.h"
+
+void arl_cleanup(arl_t *arl)
+{
+	(void) arl;
+}
+
+bool arl_handle(arl_t *arl, const char *filepath)
+{ 
+	(void) arl;
+	(void) filepath;
+	return false;
+}
+
+void arl_init(arl_t *arl)
+{
+	(void) arl;
+}
+
+void arl_setup(arl_t *arl, const char *filepath)
+{
+	(void) arl;
+	(void) filepath;
+}
+
diff --git a/main.c b/main.c
index 9e337f4..aa11616 100644
--- a/main.c
+++ b/main.c
@@ -28,6 +28,7 @@
 #include <sys/stat.h>
 #include <sys/time.h>
 #include <sys/wait.h>
+#include <time.h>
 #include <X11/keysym.h>
 #include <X11/XF86keysym.h>
 
@@ -38,6 +39,7 @@
 #include "thumbs.h"
 #include "util.h"
 #include "window.h"
+#include "autoreload.h"
 
 #define _MAPPINGS_CONFIG
 #include "config.h"
@@ -56,6 +58,7 @@ void slideshow(void);
 void clear_resize(void);
 
 appmode_t mode;
+arl_t arl;
 img_t img;
 tns_t tns;
 win_t win;
@@ -98,6 +101,7 @@ timeout_t timeouts[] = {
 void cleanup(void)
 {
 	img_close(&img, false);
+	arl_cleanup(&arl);
 	tns_free(&tns);
 	win_close(&win);
 }
@@ -317,6 +321,7 @@ void load_image(int new)
 
 	info.open = false;
 	open_info();
+	arl_setup(&arl, files[fileidx].path);
 
 	if (img.multi.cnt > 0 && img.multi.animate)
 		set_timeout(animate, img.multi.frames[img.multi.sel].delay, true);
@@ -672,6 +677,8 @@ void on_buttonpress(XButtonEvent *bev)
 	prefix = 0;
 }
 
+const struct timespec ten_ms = {0, 10000000};
+
 void run(void)
 {
 	int xfd;
@@ -685,8 +692,8 @@ void run(void)
 		init_thumb = mode == MODE_THUMB && tns.initnext < filecnt;
 		load_thumb = mode == MODE_THUMB && tns.loadnext < tns.end;
 
-		if ((init_thumb || load_thumb || to_set || info.fd != -1) &&
-		    XPending(win.env.dpy) == 0)
+		if ((init_thumb || load_thumb || to_set || info.fd != -1 ||
+			   arl.fd != -1) && XPending(win.env.dpy) == 0)
 		{
 			if (load_thumb) {
 				set_timeout(redraw, TO_REDRAW_THUMBS, false);
@@ -708,9 +715,21 @@ void run(void)
 					FD_SET(info.fd, &fds);
 					xfd = MAX(xfd, info.fd);
 				}
+				if (arl.fd != -1) {
+					FD_SET(arl.fd, &fds);
+					xfd = MAX(xfd, arl.fd);
+				}
 				select(xfd + 1, &fds, 0, 0, to_set ? &timeout : NULL);
 				if (info.fd != -1 && FD_ISSET(info.fd, &fds))
 					read_info();
+				if (arl.fd != -1 && FD_ISSET(arl.fd, &fds)) {
+					if (arl_handle(&arl)) {
+						/* when too fast, imlib2 can't load the image */
+						nanosleep(&ten_ms, NULL);
+						load_image(fileidx);
+						redraw();
+					}
+				}
 			}
 			continue;
 		}
@@ -854,6 +873,7 @@ int main(int argc, char **argv)
 
 	win_init(&win);
 	img_init(&img, &win);
+	arl_init(&arl);
 
 	if ((homedir = getenv("XDG_CONFIG_HOME")) == NULL || homedir[0] == '\0') {
 		homedir = getenv("HOME");