Refactor creation of domain_map into confdb

The NSS provider, the Data Provider backends and the InfoPipe all
need access to the domain map provided by the confdb. Instead of
reimplimenting it in multiple places, it is now provided in a pair
of helper functions from the confdb.

confdb_get_domains() returns a domain map by reference. Always
returns the most up-to-date set of domains from the confdb.

confdb_get_domains_list() returns an array of strings of all the
domain names. Always returns the most up-to-date set of domains
from the confdb.

This patch also modifies the btreemap_get_keys() function to
better handle memory and report allocation failures.

2 files changed, 39 insertions, 9 deletions

diff --git a/server/util/btreemap.c b/server/util/btreemap.c
index c9289f521..7bda0570a 100644
--- a/server/util/btreemap.c
+++ b/server/util/btreemap.c
@@ -166,21 +166,51 @@ int btreemap_set_value(TALLOC_CTX *mem_ctx,
     return EOK;
 }
 
-/* Return an array of keys in sort order
- * count should be initialized to zero before calling this function.
- */
-void btreemap_get_keys(TALLOC_CTX *mem_ctx, struct btreemap *map, const void ***array, int *count)
+static int _btreemap_get_keys(TALLOC_CTX *mem_ctx, struct btreemap *map, const void ***array, int *count, int depth)
 {
-    if (map == NULL) return;
+    int ret;
+    const void **tmp_array;
+
+    if (map == NULL) {
+        if (depth == 0) {
+            /* This is the top-level */
+            count = 0;
+            *array = NULL;
+        }
+        return EOK;
+    }
 
     /* Left Node */
-    btreemap_get_keys(mem_ctx, map->left, array, count);
+    ret = _btreemap_get_keys(mem_ctx, map->left, array, count, depth+1);
+    if (ret != EOK) {
+        return ret;
+    }
 
     /* Current Node */
     (*count)++;
-    *array = talloc_realloc(mem_ctx, *array, const void *, *count);
+    tmp_array = talloc_realloc(mem_ctx, *array, const void *, *count);
+    if (tmp_array == NULL) {
+        /* Out of memory */
+        *count = 0;
+        talloc_free(*array);
+        *array = NULL;
+        return ENOMEM;
+    }
+    *array = tmp_array;
     (*array)[(*count)-1] = map->key;
 
     /* Right Node */
-    btreemap_get_keys(mem_ctx, map->right, array, count);
+    ret = _btreemap_get_keys(mem_ctx, map->right, array, count, depth+1);
+    if (ret != EOK) {
+        return ret;
+    }
+
+    return EOK;
+}
+/* Return an array of keys in sort order
+ */
+int btreemap_get_keys(TALLOC_CTX *mem_ctx, struct btreemap *map, const void ***array, int *count)
+{
+    *array = NULL;
+    return _btreemap_get_keys(mem_ctx, map, array, count, 0);
 }
diff --git a/server/util/btreemap.h b/server/util/btreemap.h
index c5c415075..8d7fb1595 100644
--- a/server/util/btreemap.h
+++ b/server/util/btreemap.h
@@ -35,7 +35,7 @@ void *btreemap_get_value(struct btreemap *map, const void *key);
 int btreemap_set_value(TALLOC_CTX *mem_ctx,
                        struct btreemap **map, const void *key, void *value,
                        btreemap_comparison_fn comparator);
-void btreemap_get_keys(TALLOC_CTX *mem_ctx, struct btreemap *map, const void ***array, int *count);
+int btreemap_get_keys(TALLOC_CTX *mem_ctx, struct btreemap *map, const void ***array, int *count);
 
 
 #endif /*BTREEMAP_H_*/