X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=lib%2Fshash.c;h=5257de12aad4c4df7acb03809224e1e0bdd70e0c;hb=2cb0c515ea85a104a18129e3379b49c556ae4e8e;hp=002174741842cecad7c5c56eaf14d1503615bc9e;hpb=c01da229646791c0e4613d9e3fc4a1b9cc9f7d12;p=openvswitch

diff --git a/lib/shash.c b/lib/shash.c
index 00217474..5257de12 100644
--- a/lib/shash.c
+++ b/lib/shash.c
@@ -67,15 +67,26 @@ shash_count(const struct shash *shash)
 /* It is the caller's responsibility to avoid duplicate names, if that is
  * desirable. */
 struct shash_node *
-shash_add(struct shash *sh, const char *name, void *data)
+shash_add(struct shash *sh, const char *name, const void *data)
 {
     struct shash_node *node = xmalloc(sizeof *node);
     node->name = xstrdup(name);
-    node->data = data;
+    node->data = (void *) data;
     hmap_insert(&sh->map, &node->node, hash_name(name));
     return node;
 }
 
+bool
+shash_add_once(struct shash *sh, const char *name, const void *data)
+{
+    if (!shash_find(sh, name)) {
+        shash_add(sh, name, data);
+        return true;
+    } else {
+        return false;
+    }
+}
+
 void
 shash_delete(struct shash *sh, struct shash_node *node)
 {
@@ -126,3 +137,34 @@ shash_first(const struct shash *shash)
     return node ? CONTAINER_OF(node, struct shash_node, node) : NULL;
 }
 
+static int
+compare_nodes_by_name(const void *a_, const void *b_)
+{
+    const struct shash_node *const *a = a_;
+    const struct shash_node *const *b = b_;
+    return strcmp((*a)->name, (*b)->name);
+}
+
+const struct shash_node **
+shash_sort(const struct shash *sh)
+{
+    if (shash_is_empty(sh)) {
+        return NULL;
+    } else {
+        const struct shash_node **nodes;
+        struct shash_node *node;
+        size_t i, n;
+
+        n = shash_count(sh);
+        nodes = xmalloc(n * sizeof *nodes);
+        i = 0;
+        SHASH_FOR_EACH (node, sh) {
+            nodes[i++] = node;
+        }
+        assert(i == n);
+
+        qsort(nodes, n, sizeof *nodes, compare_nodes_by_name);
+
+        return nodes;
+    }
+}