Get rid of flags member in spdylay_map

lib/spdylay_map.c

@@ -24,12 +24,6 @@
  */
 #include "spdylay_map.h"
 
-typedef enum {
-  SUB_LEFT = 1,
-  SUB_RIGHT = 1 << 1,
-  SUB_ALL = (1 << 2) - 1
-} spdylay_map_subtr;
-
 void spdylay_map_init(spdylay_map *map)
 {
   map->root = NULL;
@@ -41,31 +35,102 @@ void spdylay_map_free(spdylay_map *map)
   map->root = NULL;
 }
 
+/* Find left most node, which is not necessarily a leaf. */
+static spdylay_map_entry* find_left_most(spdylay_map_entry *entry)
+{
+  while(entry->left) {
+    entry = entry->left;
+  }
+  return entry;
+}
+
+/* Find left most leaf. */
+static spdylay_map_entry* find_left_most_leaf(spdylay_map_entry *entry)
+{
+  for(;;) {
+    entry = find_left_most(entry);
+    if(entry->right) {
+      entry = entry->right;
+    } else {
+      break;
+    }
+  }
+  return entry;
+}
+
+/* Returns next node in postorder traversal. Returns NULL if there is
+   no next node. */
+static spdylay_map_entry* traverse_postorder(spdylay_map_entry *parent,
+                                             spdylay_map_entry *entry)
+{
+  if(!parent) {
+    return NULL;
+  }
+  if(parent->left == entry) {
+    if(parent->right) {
+      return find_left_most_leaf(parent->right);
+    } else {
+      return parent;
+    }
+  } else {
+    return parent;
+  }
+}
+
 void spdylay_map_each_free(spdylay_map *map,
                            int (*func)(spdylay_map_entry *entry, void *ptr),
                            void *ptr)
 {
-  spdylay_map_entry *entry = map->root;
+  spdylay_map_entry *entry;
+  if(!map->root) {
+    return;
+  }
+  entry = find_left_most_leaf(map->root);
   while(entry) {
-    if(entry->flags == SUB_ALL) {
     spdylay_map_entry *parent = entry->parent;
+    /* Ignore return value. */
     func(entry, ptr);
-      entry = parent;
+    /* entry has been deleted. */
-    } else if(entry->flags == SUB_LEFT) {
+    entry = traverse_postorder(parent, entry);
-      entry->flags |= SUB_RIGHT;
-      if(entry->right) {
-        entry = entry->right;
-      }
-    } else {
-      entry->flags |= SUB_LEFT;
-      if(entry->left) {
-        entry = entry->left;
-      }
-    }
   }
   map->root = NULL;
 }
 
+/* Returns next node in inorder traversal. Returns NULL if there is no
+   next node. */
+static spdylay_map_entry* traverse_inorder(spdylay_map_entry *entry)
+{
+  spdylay_map_entry *parent;
+  if(entry->right) {
+    return find_left_most(entry->right);
+  }
+  parent = entry->parent;
+  while(parent && parent->right == entry) {
+    entry = entry->parent;
+    parent = parent->parent;
+  }
+  return parent;
+}
+
+int spdylay_map_each(spdylay_map *map,
+                     int (*func)(spdylay_map_entry *entry, void *ptr),
+                     void *ptr)
+{
+  spdylay_map_entry *entry;
+  if(!map->root) {
+    return 0;
+  }
+  entry = find_left_most(map->root);
+  while(entry) {
+    int rv = func(entry, ptr);
+    if(rv != 0) {
+      return rv;
+    }
+    entry = traverse_inorder(entry);
+  }
+  return 0;
+}
+
 /*
  * 32 bit Mix Functions by Thomas Wang
  *
@@ -87,7 +152,6 @@ void spdylay_map_entry_init(spdylay_map_entry *entry, key_type key)
   entry->key = key;
   entry->parent = entry->left = entry->right = NULL;
   entry->priority = hash32shift(key);
-  entry->flags = 0;
 }
 
 static spdylay_map_entry* rotate_left(spdylay_map_entry *entry)
@@ -270,36 +334,3 @@ size_t spdylay_map_size(spdylay_map *map)
 {
   return map->size;
 }
-
-int spdylay_map_each(spdylay_map *map,
-                     int (*func)(spdylay_map_entry *entry, void *ptr),
-                     void *ptr)
-{
-  spdylay_map_entry *entry = map->root;
-  while(entry) {
-    if(entry->flags == SUB_ALL) {
-      entry->flags = 0;
-      entry = entry->parent;
-    } else if(entry->flags == SUB_LEFT) {
-      int rv;
-      rv = func(entry, ptr);
-      if(rv != 0) {
-        while(entry) {
-          entry->flags = 0;
-          entry = entry->parent;
-        }
-        return rv;
-      }
-      entry->flags |= SUB_RIGHT;
-      if(entry->right) {
-        entry = entry->right;
-      }
-    } else {
-      entry->flags |= SUB_LEFT;
-      if(entry->left) {
-        entry = entry->left;
-      }
-    }
-  }
-  return 0;
-}

lib/spdylay_map.h

@@ -41,7 +41,6 @@ typedef struct spdylay_map_entry {
   key_type key;
   struct spdylay_map_entry *parent, *left, *right;
   pri_type priority;
-  uint8_t flags;
 } spdylay_map_entry;
 
 typedef struct {

tests/spdylay_map_test.c

@@ -125,7 +125,7 @@ void test_spdylay_map_functional(void)
   // insertion
   shuffle(order, NUM_ENT);
   for(i = 0; i < NUM_ENT; ++i) {
-    CU_ASSERT(0 == spdylay_map_insert(&map, &arr[i].map_entry));
+    CU_ASSERT(0 == spdylay_map_insert(&map, &arr[order[i] - 1].map_entry));
   }
   // traverse
   spdylay_map_each(&map, eachfun, NULL);
@@ -140,7 +140,15 @@ void test_spdylay_map_functional(void)
     CU_ASSERT(0 == spdylay_map_remove(&map, order[i]));
   }
 
-  spdylay_map_free(&map);
+  // each_free (but no op function for testing purpose)
+  for(i = 0; i < NUM_ENT; ++i) {
+    strentry_init(&arr[i], i + 1, "foo");
+  }
+  // insert once again
+  for(i = 0; i < NUM_ENT; ++i) {
+    CU_ASSERT(0 == spdylay_map_insert(&map, &arr[i].map_entry));
+  }
+  spdylay_map_each_free(&map, eachfun, NULL);
 }
 
 static int entry_free(spdylay_map_entry *entry, void *ptr)