Add replace flag to iso_dir_add_node().

TODO

@@ -10,6 +10,7 @@ TODO
 #00003 make error.h header public
 #00004 (fsource-h) -> Add a get_mime_type() function.
 #00005 (node.c) -> optimize iso_dir_iter_take. 
+#00006 (libisofs.h) -> define more replace values when adding a node to a dir
 
 FIXME
 =====

src/libisofs.h

@@ -261,15 +261,23 @@ gid_t iso_node_get_gid(const IsoNode *node);
  *     to other dir, and that the node name is unique inside the child.
  *     Otherwise this function will return a failure, and the child won't be
  *     inserted.
+ * @param replace
+ *     if the dir already contains a node with the same name, whether to
+ *     replace or not the old node with this. 
+ *      - 0 not replace (will fail with ISO_NODE_NAME_NOT_UNIQUE)
+ *      - 1 replace 
+ *      TODO #00006 define more values
+ *          to replace only if both are the same kind of file
+ *          if both are dirs, add contents (and what to do with conflicts?)
  * @return
  *     number of nodes in dir if succes, < 0 otherwise
  *     Possible errors:
  *         ISO_NULL_POINTER, if dir or child are NULL
  *         ISO_NODE_ALREADY_ADDED, if child is already added to other dir 
  *         ISO_NODE_NAME_NOT_UNIQUE, a node with same name already exists
- *         ISO_WRONG_ARG_VALUE, if child == dir
+ *         ISO_WRONG_ARG_VALUE, if child == dir, or replace != (0,1)
  */
-int iso_dir_add_node(IsoDir *dir, IsoNode *child);
+int iso_dir_add_node(IsoDir *dir, IsoNode *child, int replace);
 
 /**
  * Locate a node inside a given dir.

src/node.c

@@ -161,7 +161,7 @@ gid_t iso_node_get_gid(const IsoNode *node)
  * @return
  *     number of nodes in dir if succes, < 0 otherwise
  */
-int iso_dir_add_node(IsoDir *dir, IsoNode *child)
+int iso_dir_add_node(IsoDir *dir, IsoNode *child, int replace)
 {
     IsoNode **pos;
     
@@ -185,7 +185,20 @@ int iso_dir_add_node(IsoDir *dir, IsoNode *child)
         pos = &((*pos)->next);
     }
     if (*pos != NULL && !strcmp((*pos)->name, child->name)) {
-        return ISO_NODE_NAME_NOT_UNIQUE;
+        /* a node with same name already exists */
+        if (replace == 0) {
+            return ISO_NODE_NAME_NOT_UNIQUE;
+        } else if (replace == 1) {
+            child->next = (*pos)->next;
+            (*pos)->parent = NULL;
+            (*pos)->next = NULL;
+            iso_node_unref(*pos);
+            *pos = child;
+            child->parent = dir;
+            return dir->nchildren;
+        } else {
+            return ISO_WRONG_ARG_VALUE;
+        }
     }
     
     child->next = *pos;