GLib Reference Manual | ||||
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#include <glib.h> GNode; GNode* g_node_new (gpointer data); GNode* g_node_copy (GNode *node); gpointer (*GCopyFunc) (gconstpointer src, gpointer data); GNode* g_node_copy_deep (GNode *node, GCopyFunc copy_func, gpointer data); GNode* g_node_insert (GNode *parent, gint position, GNode *node); GNode* g_node_insert_before (GNode *parent, GNode *sibling, GNode *node); GNode* g_node_insert_after (GNode *parent, GNode *sibling, GNode *node); #define g_node_append (parent, node) GNode* g_node_prepend (GNode *parent, GNode *node); #define g_node_insert_data (parent, position, data) #define g_node_insert_data_before (parent, sibling, data) #define g_node_append_data (parent, data) #define g_node_prepend_data (parent, data) void g_node_reverse_children (GNode *node); void g_node_traverse (GNode *root, GTraverseType order, GTraverseFlags flags, gint max_depth, GNodeTraverseFunc func, gpointer data); enum GTraverseFlags; gboolean (*GNodeTraverseFunc) (GNode *node, gpointer data); void g_node_children_foreach (GNode *node, GTraverseFlags flags, GNodeForeachFunc func, gpointer data); void (*GNodeForeachFunc) (GNode *node, gpointer data); GNode* g_node_get_root (GNode *node); GNode* g_node_find (GNode *root, GTraverseType order, GTraverseFlags flags, gpointer data); GNode* g_node_find_child (GNode *node, GTraverseFlags flags, gpointer data); gint g_node_child_index (GNode *node, gpointer data); gint g_node_child_position (GNode *node, GNode *child); #define g_node_first_child (node) GNode* g_node_last_child (GNode *node); GNode* g_node_nth_child (GNode *node, guint n); GNode* g_node_first_sibling (GNode *node); #define g_node_next_sibling (node) #define g_node_prev_sibling (node) GNode* g_node_last_sibling (GNode *node); #define G_NODE_IS_LEAF (node) #define G_NODE_IS_ROOT (node) guint g_node_depth (GNode *node); guint g_node_n_nodes (GNode *root, GTraverseFlags flags); guint g_node_n_children (GNode *node); gboolean g_node_is_ancestor (GNode *node, GNode *descendant); guint g_node_max_height (GNode *root); void g_node_unlink (GNode *node); void g_node_destroy (GNode *root); void g_node_push_allocator (gpointer dummy); void g_node_pop_allocator (void);
The GNode struct and its associated functions provide a N-ary tree data structure, where nodes in the tree can contain arbitrary data.
To create a new tree use g_node_new()
.
To insert a node into a tree use g_node_insert()
, g_node_insert_before()
,
g_node_append()
and g_node_prepend()
.
To create a new node and insert it into a tree use g_node_insert_data()
,
g_node_insert_data_before()
, g_node_append_data()
and g_node_prepend_data()
.
To reverse the children of a node use g_node_reverse_children()
.
To find a node use g_node_get_root()
, g_node_find()
, g_node_find_child()
,
g_node_child_index()
, g_node_child_position()
,
g_node_first_child()
, g_node_last_child()
,
g_node_nth_child()
, g_node_first_sibling()
, g_node_prev_sibling()
,
g_node_next_sibling()
or g_node_last_sibling()
.
To get information about a node or tree use G_NODE_IS_LEAF()
,
G_NODE_IS_ROOT()
, g_node_depth()
, g_node_n_nodes()
, g_node_n_children()
,
g_node_is_ancestor()
or g_node_max_height()
.
To traverse a tree, calling a function for each node visited in the
traversal, use g_node_traverse()
or g_node_children_foreach()
.
To remove a node or subtree from a tree use g_node_unlink()
or
g_node_destroy()
.
typedef struct { gpointer data; GNode *next; GNode *prev; GNode *parent; GNode *children; } GNode;
The GNode struct represents one node in a
N-ary Tree.
The data
field contains the actual data of the node.
The next
and prev
fields point to the node's siblings (a sibling is another GNode with the
same parent).
The parent
field points to the parent of the GNode,
or is NULL
if the GNode is the root of the tree.
The children
field points to the first child of the
GNode. The other children are accessed by using the
next
pointer of each child.
GNode* g_node_new (gpointer data);
Creates a new GNode containing the given data. Used to create the first node in a tree.
data : |
the data of the new node. |
Returns : | a new GNode. |
GNode* g_node_copy (GNode *node);
Recursively copies a GNode (but does not deep-copy the data inside the nodes,
see g_node_copy_deep()
if you need that).
gpointer (*GCopyFunc) (gconstpointer src, gpointer data);
A function of this signature is used to copy the node data when doing a deep-copy of a tree.
src : |
A pointer to the data which should be copied. |
data : |
Additional data. |
Returns : | A pointer to the copy. |
Since 2.4
GNode* g_node_copy_deep (GNode *node, GCopyFunc copy_func, gpointer data);
Recursively copies a GNode and its data.
node : |
a GNode |
copy_func : |
the function which is called to copy the data inside each node,
or NULL to use the original data.
|
data : |
data to pass to copy_func
|
Returns : | a new GNode containing copies of the data in node .
|
Since 2.4
GNode* g_node_insert (GNode *parent, gint position, GNode *node);
Inserts a GNode beneath the parent at the given position.
GNode* g_node_insert_before (GNode *parent, GNode *sibling, GNode *node);
Inserts a GNode beneath the parent before the given sibling.
GNode* g_node_insert_after (GNode *parent, GNode *sibling, GNode *node);
Inserts a GNode beneath the parent after the given sibling.
#define g_node_append(parent, node)
Inserts a GNode as the last child of the given parent.
GNode* g_node_prepend (GNode *parent, GNode *node);
Inserts a GNode as the first child of the given parent.
#define g_node_insert_data(parent, position, data)
Inserts a new GNode at the given position.
#define g_node_insert_data_before(parent, sibling, data)
Inserts a new GNode before the given sibling.
#define g_node_append_data(parent, data)
Inserts a new GNode as the last child of the given parent.
#define g_node_prepend_data(parent, data)
Inserts a new GNode as the first child of the given parent.
void g_node_reverse_children (GNode *node);
Reverses the order of the children of a GNode. (It doesn't change the order of the grandchildren.)
node : |
a GNode. |
void g_node_traverse (GNode *root, GTraverseType order, GTraverseFlags flags, gint max_depth, GNodeTraverseFunc func, gpointer data);
Traverses a tree starting at the given root GNode.
It calls the given function for each node visited.
The traversal can be halted at any point by returning TRUE
from func
.
root : |
the root GNode of the tree to traverse. |
order : |
the order in which nodes are visited - G_IN_ORDER , G_PRE_ORDER ,
G_POST_ORDER , or G_LEVEL_ORDER .
|
flags : |
which types of children are to be visited, one of G_TRAVERSE_ALL ,
G_TRAVERSE_LEAVES and G_TRAVERSE_NON_LEAVES .
|
max_depth : |
the maximum depth of the traversal. Nodes below this depth will not be visited. If max_depth is -1 all nodes in the tree are visited. If depth is 1, only the root is visited. If depth is 2, the root and its children are visited. And so on. |
func : |
the function to call for each visited GNode. |
data : |
user data to pass to the function. |
typedef enum { G_TRAVERSE_LEAVES = 1 << 0, G_TRAVERSE_NON_LEAVES = 1 << 1, G_TRAVERSE_ALL = G_TRAVERSE_LEAVES | G_TRAVERSE_NON_LEAVES, G_TRAVERSE_MASK = 0x03, G_TRAVERSE_LEAFS = G_TRAVERSE_LEAVES, G_TRAVERSE_NON_LEAFS = G_TRAVERSE_NON_LEAVES } GTraverseFlags;
Specifies which nodes are visited during several of the tree functions,
including g_node_traverse()
and g_node_find()
.
G_TRAVERSE_LEAVES |
only leaf nodes should be visited. This name has been
introduced in 2.6, for older version use G_TRAVERSE_LEAFS .
|
G_TRAVERSE_NON_LEAVES |
only non-leaf nodes should be visited. This name
has been introduced in 2.6, for older version use G_TRAVERSE_NON_LEAFS .
|
G_TRAVERSE_ALL |
all nodes should be visited. |
G_TRAVERSE_MASK |
|
G_TRAVERSE_LEAFS |
identical to G_TRAVERSE_LEAVES
|
G_TRAVERSE_NON_LEAFS |
identical to G_TRAVERSE_NON_LEAVES
|
gboolean (*GNodeTraverseFunc) (GNode *node, gpointer data);
Specifies the type of function passed to g_node_traverse()
.
The function is called with each of the nodes visited, together with the
user data passed to g_node_traverse()
.
If the function returns TRUE
, then the traversal is stopped.
node : |
a GNode. |
data : |
user data passed to g_node_traverse() .
|
Returns : |
TRUE to stop the traversal.
|
void g_node_children_foreach (GNode *node, GTraverseFlags flags, GNodeForeachFunc func, gpointer data);
Calls a function for each of the children of a GNode. Note that it doesn't descend beneath the child nodes.
node : |
a GNode. |
flags : |
which types of children are to be visited, one of G_TRAVERSE_ALL ,
G_TRAVERSE_LEAVES and G_TRAVERSE_NON_LEAVES .
|
func : |
the function to call for each visited node. |
data : |
user data to pass to the function. |
void (*GNodeForeachFunc) (GNode *node, gpointer data);
Specifies the type of function passed to g_node_children_foreach()
.
The function is called with each child node, together with the user data
passed to g_node_children_foreach()
.
node : |
a GNode. |
data : |
user data passed to g_node_children_foreach() .
|
GNode* g_node_get_root (GNode *node);
Gets the root of a tree.
node : |
a GNode. |
Returns : | the root of the tree. |
GNode* g_node_find (GNode *root, GTraverseType order, GTraverseFlags flags, gpointer data);
Finds a GNode in a tree.
root : |
the root GNode of the tree to search. |
order : |
the order in which nodes are visited - G_IN_ORDER , G_PRE_ORDER ,
G_POST_ORDER , or G_LEVEL_ORDER .
|
flags : |
which types of children are to be searched, one of G_TRAVERSE_ALL ,
G_TRAVERSE_LEAVES and G_TRAVERSE_NON_LEAVES .
|
data : |
the data to find. |
Returns : | the found GNode, or NULL if the data is not found.
|
GNode* g_node_find_child (GNode *node, GTraverseFlags flags, gpointer data);
Finds the first child of a GNode with the given data.
node : |
a GNode. |
flags : |
which types of children are to be searched, one of G_TRAVERSE_ALL ,
G_TRAVERSE_LEAVES and G_TRAVERSE_NON_LEAVES .
|
data : |
the data to find. |
Returns : | the found child GNode, or NULL if the data is not found.
|
gint g_node_child_index (GNode *node, gpointer data);
Gets the position of the first child of a GNode which contains the given data.
node : |
a GNode. |
data : |
the data to find. |
Returns : | the index of the child of node which contains data , or -1
if the data is not found.
|
gint g_node_child_position (GNode *node, GNode *child);
Gets the position of a GNode with respect to its siblings.
child
must be a child of node
.
The first child is numbered 0, the second 1, and so on.
node : |
a GNode. |
child : |
a child of node .
|
Returns : | the position of child with respect to its siblings.
|
GNode* g_node_nth_child (GNode *node, guint n);
Gets a child of a GNode, using the given index.
The first child is at index 0. If the index is too big, NULL
is returned.
node : |
a GNode. |
n : |
the index of the desired child. |
Returns : | the child of node at index n .
|
GNode* g_node_first_sibling (GNode *node);
Gets the first sibling of a GNode. This could possibly be the node itself.
node : |
a GNode. |
Returns : | the first sibling of node .
|
GNode* g_node_last_sibling (GNode *node);
Gets the last sibling of a GNode. This could possibly be the node itself.
node : |
a GNode. |
Returns : | the last sibling of node .
|
guint g_node_depth (GNode *node);
Gets the depth of a GNode.
If node
is NULL
the depth is 0.
The root node has a depth of 1.
For the children of the root node the depth is 2. And so on.
guint g_node_n_nodes (GNode *root, GTraverseFlags flags);
Gets the number of nodes in a tree.
root : |
a GNode. |
flags : |
which types of children are to be counted, one of G_TRAVERSE_ALL ,
G_TRAVERSE_LEAVES and G_TRAVERSE_NON_LEAVES .
|
Returns : | the number of nodes in the tree. |
guint g_node_n_children (GNode *node);
Gets the number of children of a GNode.
node : |
a GNode. |
Returns : | the number of children of node .
|
gboolean g_node_is_ancestor (GNode *node, GNode *descendant);
Returns TRUE
if node
is an ancestor of descendant
.
This is true if node is the parent of descendant
, or if node is the
grandparent of descendant
etc.
guint g_node_max_height (GNode *root);
Gets the maximum height of all branches beneath a GNode. This is the maximum distance from the GNode to all leaf nodes.
If root
is NULL
, 0 is returned. If root
has no children, 1 is returned.
If root
has children, 2 is returned. And so on.
root : |
a GNode. |
Returns : | the maximum height of the tree beneath root .
|
void g_node_unlink (GNode *node);
Unlinks a GNode from a tree, resulting in two separate trees.
node : |
the GNode to unlink, which becomes the root of a new tree. |
void g_node_destroy (GNode *root);
Removes the GNode and its children from the tree, freeing any memory allocated.
root : |
the root of the tree/subtree to destroy. |
void g_node_push_allocator (gpointer dummy);
g_node_push_allocator
has been deprecated since version 2.10 and should not be used in newly-written code. It does nothing, since GNode has been converted
to the slice allocator
Sets the allocator to use to allocate GNode elements.
Use g_node_pop_allocator()
to restore the previous allocator.
Note that this function is not available if GLib has been compiled
with --disable-mem-pools
dummy : |
the GAllocator to use when allocating GNode elements. |
void g_node_pop_allocator (void);
g_node_pop_allocator
has been deprecated since version 2.10 and should not be used in newly-written code. It does nothing, since GNode has been converted
to the slice allocator
Restores the previous GAllocator, used when allocating GNode elements.
Note that this function is not available if GLib has been compiled
with --disable-mem-pools