Merge pull request #68 from czarkoff/reload

Use stat(2) to monitor file changes

src/main.c

@@ -28,7 +28,6 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 #include "navigator.h"
 #include "viewport.h"
 #include "util.h"
-#include "reload.h"
 
 struct {
   int fullscreen;
@@ -285,9 +284,6 @@ int main(int argc, char** argv)
   struct imv_viewport view;
   imv_init_viewport(&view, window);
 
-  struct imv_reload reload;
-  imv_init_reload(&reload);
-
   /* put us in fullscren mode to begin with if requested */
   if(g_options.fullscreen) {
     imv_viewport_toggle_fullscreen(&view);
@@ -422,7 +418,7 @@ int main(int argc, char** argv)
     }
 
     /* if the user has changed image, start loading the new one */
-    if(imv_navigator_poll_changed(&nav) || imv_reload_changed(&reload)) {
+    if(imv_navigator_poll_changed(&nav)) {
       const char *current_path = imv_navigator_selection(&nav);
       if(!current_path) {
         fprintf(stderr, "No input files left. Exiting.\n");
@@ -435,7 +431,6 @@ int main(int argc, char** argv)
       imv_viewport_set_title(&view, title);
 
       imv_loader_load_path(&ldr, current_path);
-      imv_reload_watch(&reload, current_path);
       view.playing = 1;
     }
 
@@ -574,7 +569,6 @@ int main(int argc, char** argv)
   imv_destroy_texture(&tex);
   imv_navigator_destroy(&nav);
   imv_destroy_viewport(&view);
-  imv_destroy_reload(&reload);
 
   if(font) {
     TTF_CloseFont(font);

src/navigator.c

@@ -27,6 +27,16 @@ void imv_navigator_init(struct imv_navigator *nav)
 {
   nav->buf_size = 512;
   nav->paths = malloc(sizeof(char*) * nav->buf_size);
+  if (nav->paths == NULL) {
+    perror("imv_navigator_init");
+    exit(1);
+  }
+  nav->mtimes = malloc(sizeof(time_t) * nav->buf_size);
+  if (nav->paths == NULL) {
+    perror("imv_navigator_init");
+    free(nav->paths);
+    exit(1);
+  }
   nav->num_paths = 0;
   nav->cur_path = 0;
   nav->last_move_direction = 1;
@@ -38,22 +48,33 @@ void imv_navigator_destroy(struct imv_navigator *nav)
   if(nav->buf_size > 0) {
     free(nav->paths);
     nav->paths = NULL;
+    free(nav->mtimes);
+    nav->mtimes = NULL;
     nav->buf_size = 0;
   }
   nav->num_paths = 0;
 }
 
-static void add_item(struct imv_navigator *nav, const char *path)
+static void add_item(struct imv_navigator *nav, const char *path,
+                     time_t mtime)
 {
   if(nav->buf_size == nav->num_paths) {
-    int new_buf_size = nav->buf_size * 2;
-    char **new_paths = malloc(sizeof(char*) * new_buf_size);
-    memcpy(new_paths, nav->paths, sizeof(char*) * nav->buf_size);
-    free(nav->paths);
+    char **new_paths;
+    time_t *new_mtimes;
+    nav->buf_size *= 2;
+    new_paths = realloc(nav->paths, sizeof(char*) * nav->buf_size);
+    new_mtimes = realloc(nav->mtimes, sizeof(time_t) * nav->buf_size);
+    if (new_paths == NULL || new_mtimes == NULL) {
+      perror("add_item");
+      free(nav->paths);
+      free(nav->mtimes);
+      exit(1);
+    }
     nav->paths = new_paths;
-    nav->buf_size = new_buf_size;
+    nav->mtimes = new_mtimes;
   }
   nav->paths[nav->num_paths] = strdup(path);
+  nav->mtimes[nav->num_paths] = mtime;
   nav->num_paths += 1;
   if(nav->num_paths == 1) {
     nav->changed = 1;
@@ -79,13 +100,13 @@ void imv_navigator_add(struct imv_navigator *nav, const char *path,
         if(recursive) {
           imv_navigator_add(nav, path_buf, recursive);
         } else {
-          add_item(nav, path_buf);
+          add_item(nav, path_buf, path_info.st_mtim.tv_sec);
         }
       }
       closedir(d);
     }
   } else {
-   add_item(nav, path); 
+   add_item(nav, path, path_info.st_mtim.tv_sec); 
   }
 }
 
@@ -195,6 +216,13 @@ int imv_navigator_poll_changed(struct imv_navigator *nav)
     nav->changed = 0;
     return 1;
   } else {
+    struct stat file_info;
+    if (stat(nav->paths[nav->cur_path], &file_info) == -1)
+      return 0;
+    if (nav->mtimes[nav->cur_path] != file_info.st_mtim.tv_sec) {
+      nav->mtimes[nav->cur_path] = file_info.st_mtim.tv_sec;
+      return 1;
+    }
     return 0;
   }
 }

src/navigator.h

@@ -1,6 +1,8 @@
 #ifndef IMV_NAVIGATOR_H
 #define IMV_NAVIGATOR_H
 
+#include <time.h>
+
 /* Copyright (c) 2015 Harry Jeffery
 
 This program is free software; you can redistribute it and/or
@@ -23,6 +25,7 @@ struct imv_navigator {
   int buf_size;
   int cur_path;
   char **paths;
+  time_t *mtimes;
   int last_move_direction;
   int changed;
 };
@@ -57,7 +60,8 @@ void imv_navigator_select_str(struct imv_navigator *nav, const int path);
 /* Return the index of the path given. Returns -1 if not found. */
 int imv_navigator_find_path(struct imv_navigator *nav, const char *path);
 
-/* Returns 1 if the currently selected path has changed since last called */
+/* Returns 1 if either the currently selected path or underlying file has
+ * changed since last called */
 int imv_navigator_poll_changed(struct imv_navigator *nav);
 
 #endif

src/reload.c

@@ -1,49 +0,0 @@
-#include <sys/inotify.h>
-#include <stdio.h>
-#include <unistd.h>
-#include <errno.h>
-
-#include "reload.h"
-
-void imv_init_reload(struct imv_reload *rld)
-{
-  rld->fd = inotify_init1(IN_NONBLOCK);
-  if(rld->fd == -1) {
-    perror("imv_init_reload");
-  }
-
-  rld->wd = 0;
-}
-
-void imv_reload_watch(struct imv_reload *rld, const char *path)
-{
-  if(rld->wd != 0) {
-    inotify_rm_watch(rld->fd, rld->wd);
-  }
-
-  rld->wd = inotify_add_watch(rld->fd, path, IN_CLOSE_WRITE);
-  if(rld->wd == -1) {
-    perror("imv_reload_watch");
-  }
-}
-
-int imv_reload_changed(struct imv_reload *rld)
-{
-  struct inotify_event ev;
-  ssize_t len = read(rld->fd, &ev, sizeof(ev));
-
-  if(len < 0) {
-    if(errno != EAGAIN) {
-      perror("imv_reload_changed");
-    }
-  } else if(ev.mask & IN_CLOSE_WRITE) {
-    return 1;
-  }
-
-  return 0;
-}
-
-void imv_destroy_reload(struct imv_reload *rld)
-{
-  close(rld->fd);
-}

src/reload.h

@@ -1,31 +0,0 @@
-#ifndef IMV_RELOAD_H
-#define IMV_RELOAD_H
-
-/* Copyright (c) 2015 Jose Diez 
-
-This program 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.
-
-This program 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 this program; if not, write to the Free Software
-Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
-*/
-
-struct imv_reload { 
-  int fd; // inotify file descriptor
-  int wd; // watch descriptor
-};
-
-void imv_init_reload(struct imv_reload *rld);
-void imv_reload_watch(struct imv_reload *rld, const char *path);
-int imv_reload_changed(struct imv_reload *rld);
-void imv_destroy_reload(struct imv_reload *rld);
-
-#endif