inotify: breakup mapping into a module.

src/inotify-map.c

@@ -0,0 +1,166 @@
+/* inotify-map.c
+ * 
+ *  (C) Copyright 2011 Henrik Hautakoski <henrik@fiktivkod.org>
+ *
+ *  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 3 of the License, or
+ *  (at your option) any later version.
+ */
+
+#include "xalloc.h"
+#include "rbtree.h"
+#include "inotify-map.h"
+
+/*
+ * IMPORTANT: always have the member used for comparison as the first member
+ * to make it possible to cast a struct pointer to the first member type.
+ */
+struct map_wd {
+    int wd;
+    struct str_list paths;
+};
+
+struct map_path {
+    const char *path;
+    int wd;
+};
+
+static void wd_free(void *ptr);
+static int wd_cmp(const void *a, const void *b);
+static int path_cmp(const void *a, const void *b);
+
+static rbtree tree_wd_paths = RBTREE_INIT(wd_free, NULL, wd_cmp);
+static rbtree tree_path_wd = RBTREE_INIT(xfree, NULL, path_cmp);
+
+static int wd_cmp(const void *a, const void *b) {
+
+    return *((int*)a) - *((int*)b);
+}
+
+static int path_cmp(const void *a, const void *b) {
+
+    return strcmp(*((char**)a), *((char**)b));
+}
+
+static void wd_free(void *ptr) {
+
+    struct map_wd *m = (struct map_wd*)ptr;
+
+    str_list_clear(&m->paths);
+    xfree(m);
+}
+
+static void map_path_wd(const char *path, int wd) {
+
+    struct map_path *p = rbtree_search(&tree_path_wd, &path);
+    if (!p) {
+        p = xmalloc(sizeof(struct map_path));
+        p->path = path;
+        rbtree_insert(&tree_path_wd, p);
+    }
+    p->wd = wd;
+}
+
+static int unmap_path_wd(int wd, const char *path) {
+
+    return rbtree_delete(&tree_path_wd, &path);
+}
+
+static void unmap_wd_path(int wd, const char *path) {
+
+    struct map_wd *m = rbtree_search(&tree_wd_paths, &wd);
+
+    if (m) {
+        char *p = str_list_remove(&m->paths, path);
+        if (p) {
+            xfree(p);
+            if (str_list_isempty(&m->paths))
+                rbtree_delete(&tree_wd_paths, m);
+        }
+    }
+}
+
+/*
+ * unmaps all paths from the 'struct map_wd' and from the search tree 'tree_path_wd'.
+ */
+static void unmap_all_paths(struct map_wd *map) {
+
+    char *path;
+
+    while(path = str_list_reduce(&map->paths)) {
+        rbtree_delete(&tree_path_wd, &path);
+        xfree(path);
+    }
+}
+
+void inotify_map(int wd, const char *path) {
+
+    struct map_wd *m = rbtree_search(&tree_wd_paths, &wd);
+    if (!m) {
+        m = xmalloc(sizeof(struct map_wd));
+        m->wd = wd;
+        str_list_init(&m->paths);
+        rbtree_insert(&tree_wd_paths, m);
+    }
+
+    if (!str_list_has(&m->paths, path)) {
+        int index = str_list_insert(&m->paths, xstrdup(path));
+        map_path_wd(m->paths.items[index], wd);
+    }
+}
+
+int inotify_unmap_wd(int wd) {
+    
+    struct map_wd *m = rbtree_search(&tree_wd_paths, &wd);
+    if (m) {
+        unmap_all_paths(m);
+        return rbtree_delete(&tree_wd_paths, &wd);
+    }
+    return 0;
+}
+
+int inotify_unmap_path(const char *path) {
+
+    struct map_path *m = rbtree_search(&tree_path_wd, &path);
+    
+    if (m) {
+        int wd = m->wd;
+        unmap_path_wd(wd, path);
+        unmap_wd_path(wd, path);
+        return 1;
+    }
+    return 0;
+}
+
+void inotify_unmap_all() {
+
+    rbtree_free(&tree_path_wd);
+    rbtree_free(&tree_wd_paths);
+}
+
+int inotify_map_get_wd(const char *path) {
+
+    struct map_path *p = rbtree_search(&tree_path_wd, &path);
+    if (p)
+        return p->wd;
+    return 0;
+}
+
+const struct str_list* inotify_map_lookup(int wd) {
+
+    struct map_wd *m = rbtree_search(&tree_wd_paths, &wd);
+    return m ? &m->paths : NULL;
+}
+
+const struct str_list* inotify_map_lookup_by_path(const char *path) {
+
+    struct map_path *p = rbtree_search(&tree_path_wd, &path);
+    return p ? inotify_map_lookup(p->wd) : NULL;
+}
+
+int inotify_map_isempty() {
+
+    return rbtree_is_empty(&tree_wd_paths)
+        && rbtree_is_empty(&tree_path_wd);
+}