Added functions for btree iteration.

diff --git a/common/utils.c b/common/utils.c
index 701f162..7a7de92 100644 (file)
--- a/common/utils.c
+++ b/common/utils.c
@@ -37,6 +37,14 @@
 #include <utils.h>
 #include <log.h>
 
+struct treeiter {
+    struct {
+       struct btree *n;
+       int s;
+    } *st;
+    size_t stsize, sp;
+};
+
 static char *base64set = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
 static int base64rev[] = {
     -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
@@ -1030,3 +1038,93 @@ void *btreeget(struct btree *tree, void *key, int (*cmp)(void *, void *))
     }
 }
 
+void btreefree(struct btree *tree)
+{
+    if(tree == NULL)
+       return;
+    btreefree(tree->l);
+    btreefree(tree->r);
+    free(tree);
+}
+
+static void *btreenext(void **iterp)
+{
+    struct treeiter *iter;
+    int s;
+    struct btree *n;
+    
+    if((iter = *iterp) == NULL)
+       return(NULL);
+    while(1) {
+       s = iter->st[iter->sp].s;
+       n = iter->st[iter->sp].n;
+       if(s == 0) {
+           iter->st[iter->sp].s = 1;
+           if(n->l != NULL) {
+               iter->sp++;
+               sizebuf2(iter->st, iter->sp + 1, 1);
+               iter->st[iter->sp].s = 0;
+               iter->st[iter->sp].n = n->l;
+           }
+       } else if(s == 1) {
+           iter->st[iter->sp].s = 2;
+           return(iter->st[iter->sp].n->d);
+       } else if(s == 2) {
+           iter->st[iter->sp].s = 3;
+           if(n->r != NULL) {
+               iter->sp++;
+               sizebuf2(iter->st, iter->sp + 1, 1);
+               iter->st[iter->sp].s = 0;
+               iter->st[iter->sp].n = n->r;
+           }
+       } else {
+           iter->sp--;
+           if(iter->sp < 0) {
+               free(iter->st);
+               free(iter);
+               *iterp = NULL;
+               return(NULL);
+           }
+       }
+    }
+}
+
+static void *btreefirst(struct btree *tree, void **iterp)
+{
+    struct treeiter *iter;
+    
+    if(tree == NULL) {
+       *iterp = NULL;
+       return(NULL);
+    }
+    *iterp = iter = memset(smalloc(sizeof(*iter)), 0, sizeof(*iter));
+    sizebuf2(iter->st, 1, 1);
+    iter->st[0].n = tree;
+    iter->st[0].s = 0;
+    return(btreenext(iterp));
+}
+
+static void btreestop(void **iterp)
+{
+    struct treeiter *iter;
+    
+    if((iter = *iterp) == NULL)
+       return;
+    if(iter->st != NULL)
+       free(iter->st);
+    free(iter);
+    *iterp = NULL;
+}
+
+void *btreeiter(struct btree *tree)
+{
+    static void *iter = NULL;
+    
+    if(tree == NULL) {
+       return(btreenext(&iter));
+    } else {
+       if(iter != NULL)
+           btreestop(&iter);
+       return(btreefirst(tree, &iter));
+    }
+}

diff --git a/include/utils.h b/include/utils.h
index cff0025..390d3b4 100644 (file)
--- a/include/utils.h
+++ b/include/utils.h
@@ -115,6 +115,8 @@ wchar_t *wpfind(struct wcspair *list, wchar_t *key);
 int bbtreedel(struct btree **tree, void *item, int (*cmp)(void *, void *));
 int bbtreeput(struct btree **tree, void *item, int (*cmp)(void *, void *));
 void *btreeget(struct btree *tree, void *key, int (*cmp)(void *, void *));
+void *btreeiter(struct btree *tree);
+void btreefree(struct btree *tree);
 
 #define sizebuf(b, bs, rs, es, a) _sizebuf((void **)(void *)(b), (bs), (rs), (es), (a))
 #define sizebuf2(b, rs, a) _sizebuf((void **)(void *)(&(b)), &(b ## size), (rs), sizeof(*(b)), (a))