gnode.c

   1 /* GLIB - Library of useful routines for C programming
   2  * Copyright (C) 1995-1997  Peter Mattis, Spencer Kimball and Josh MacDonald
   3  *
   4  * GNode: N-way tree implementation.
   5  * Copyright (C) 1998 Tim Janik
   6  *
   7  * This library is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2 of the License, or (at your option) any later version.
  11  *
  12  * This library is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with this library; if not, write to the
  19  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  20  * Boston, MA 02111-1307, USA.
  21  */
  22
  23 /*
  24  * Modified by the GLib Team and others 1997-2000.  See the AUTHORS
  25  * file for a list of people on the GLib Team.  See the ChangeLog
  26  * files for a list of changes.  These files are distributed with
  27  * GLib at ftp://ftp.gtk.org/pub/gtk/.
  28  */
  29
  30 /*
  31  * MT safe
  32  */
  33
  34 #ifdef HAVE_CONFIG_H
  35 #include <config.h>
  36 #endif
  37
  38 #include "glib.h"
  39
  40 #ifndef DISABLE_MEM_POOLS
  41 /* node allocation
  42  */
  43 struct _GAllocator /* from gmem.c */
  44 {
  45   gchar         *name;
  46   guint16        n_preallocs;
  47   guint          is_unused : 1;
  48   guint          type : 4;
  49   GAllocator    *last;
  50   GMemChunk     *mem_chunk;
  51   GNode         *free_nodes; /* implementation specific */
  52 };
  53
  54 G_LOCK_DEFINE_STATIC (current_allocator);
  55 static GAllocator *current_allocator = NULL;
  56
  57 /* HOLDS: current_allocator_lock */
  58 static void
  59 g_node_validate_allocator (GAllocator *allocator)
  60 {
  61   g_return_if_fail (allocator != NULL);
  62   g_return_if_fail (allocator->is_unused == TRUE);
  63
  64   if (allocator->type != G_ALLOCATOR_NODE)
  65     {
  66       allocator->type = G_ALLOCATOR_NODE;
  67       if (allocator->mem_chunk)
  68         {
  69           g_mem_chunk_destroy (allocator->mem_chunk);
  70           allocator->mem_chunk = NULL;
  71         }
  72     }
  73
  74   if (!allocator->mem_chunk)
  75     {
  76       allocator->mem_chunk = g_mem_chunk_new (allocator->name,
  77                                               sizeof (GNode),
  78                                               sizeof (GNode) * allocator->n_preallocs,
  79                                               G_ALLOC_ONLY);
  80       allocator->free_nodes = NULL;
  81     }
  82
  83   allocator->is_unused = FALSE;
  84 }
  85
  86 void
  87 g_node_push_allocator (GAllocator *allocator)
  88 {
  89   G_LOCK (current_allocator);
  90   g_node_validate_allocator (allocator);
  91   allocator->last = current_allocator;
  92   current_allocator = allocator;
  93   G_UNLOCK (current_allocator);
  94 }
  95
  96 void
  97 g_node_pop_allocator (void)
  98 {
  99   G_LOCK (current_allocator);
 100   if (current_allocator)
 101     {
 102       GAllocator *allocator;
 103
 104       allocator = current_allocator;
 105       current_allocator = allocator->last;
 106       allocator->last = NULL;
 107       allocator->is_unused = TRUE;
 108     }
 109   G_UNLOCK (current_allocator);
 110 }
 111
 112
 113 /* --- functions --- */
 114 GNode*
 115 g_node_new (gpointer data)
 116 {
 117   GNode *node;
 118
 119   G_LOCK (current_allocator);
 120   if (!current_allocator)
 121     {
 122        GAllocator *allocator = g_allocator_new ("GLib default GNode allocator",
 123                                                 128);
 124        g_node_validate_allocator (allocator);
 125        allocator->last = NULL;
 126        current_allocator = allocator;
 127     }
 128   if (!current_allocator->free_nodes)
 129     node = g_chunk_new (GNode, current_allocator->mem_chunk);
 130   else
 131     {
 132       node = current_allocator->free_nodes;
 133       current_allocator->free_nodes = node->next;
 134     }
 135   G_UNLOCK (current_allocator);
 136
 137   node->data = data;
 138   node->next = NULL;
 139   node->prev = NULL;
 140   node->parent = NULL;
 141   node->children = NULL;
 142
 143   return node;
 144 }
 145
 146 static void
 147 g_nodes_free (GNode *node)
 148 {
 149   GNode *parent;
 150
 151   parent = node;
 152   while (1)
 153     {
 154       if (parent->children)
 155         g_nodes_free (parent->children);
 156
 157 #ifdef ENABLE_GC_FRIENDLY
 158       parent->data = NULL;
 159       parent->prev = NULL;
 160       parent->parent = NULL;
 161       parent->children = NULL;
 162 #endif /* ENABLE_GC_FRIENDLY */
 163
 164       if (parent->next)
 165         parent = parent->next;
 166       else
 167         break;
 168     }
 169
 170   G_LOCK (current_allocator);
 171   parent->next = current_allocator->free_nodes;
 172   current_allocator->free_nodes = node;
 173   G_UNLOCK (current_allocator);
 174 }
 175 #else /* DISABLE_MEM_POOLS */
 176
 177 GNode*
 178 g_node_new (gpointer data)
 179 {
 180   GNode *node;
 181
 182   node = g_new0 (GNode, 1);
 183
 184   node->data = data;
 185
 186   return node;
 187 }
 188
 189 static void
 190 g_nodes_free (GNode *root)
 191 {
 192   GNode *node, *next;
 193
 194   node = root;
 195   while (node != NULL)
 196     {
 197       next = node->next;
 198       g_nodes_free (node->children);
 199       g_free (node);
 200       node = next;
 201     }
 202 }
 203 #endif
 204
 205 void
 206 g_node_destroy (GNode *root)
 207 {
 208   g_return_if_fail (root != NULL);
 209
 210   if (!G_NODE_IS_ROOT (root))
 211     g_node_unlink (root);
 212
 213   g_nodes_free (root);
 214 }
 215
 216 void
 217 g_node_unlink (GNode *node)
 218 {
 219   g_return_if_fail (node != NULL);
 220
 221   if (node->prev)
 222     node->prev->next = node->next;
 223   else if (node->parent)
 224     node->parent->children = node->next;
 225   node->parent = NULL;
 226   if (node->next)
 227     {
 228       node->next->prev = node->prev;
 229       node->next = NULL;
 230     }
 231   node->prev = NULL;
 232 }
 233
 234 GNode*
 235 g_node_copy (GNode *node)
 236 {
 237   GNode *new_node = NULL;
 238
 239   if (node)
 240     {
 241       GNode *child;
 242
 243       new_node = g_node_new (node->data);
 244
 245       for (child = g_node_last_child (node); child; child = child->prev)
 246         g_node_prepend (new_node, g_node_copy (child));
 247     }
 248
 249   return new_node;
 250 }
 251
 252 GNode*
 253 g_node_insert (GNode *parent,
 254                gint   position,
 255                GNode *node)
 256 {
 257   g_return_val_if_fail (parent != NULL, node);
 258   g_return_val_if_fail (node != NULL, node);
 259   g_return_val_if_fail (G_NODE_IS_ROOT (node), node);
 260
 261   if (position > 0)
 262     return g_node_insert_before (parent,
 263                                  g_node_nth_child (parent, position),
 264                                  node);
 265   else if (position == 0)
 266     return g_node_prepend (parent, node);
 267   else /* if (position < 0) */
 268     return g_node_append (parent, node);
 269 }
 270
 271 GNode*
 272 g_node_insert_before (GNode *parent,
 273                       GNode *sibling,
 274                       GNode *node)
 275 {
 276   g_return_val_if_fail (parent != NULL, node);
 277   g_return_val_if_fail (node != NULL, node);
 278   g_return_val_if_fail (G_NODE_IS_ROOT (node), node);
 279   if (sibling)
 280     g_return_val_if_fail (sibling->parent == parent, node);
 281
 282   node->parent = parent;
 283
 284   if (sibling)
 285     {
 286       if (sibling->prev)
 287         {
 288           node->prev = sibling->prev;
 289           node->prev->next = node;
 290           node->next = sibling;
 291           sibling->prev = node;
 292         }
 293       else
 294         {
 295           node->parent->children = node;
 296           node->next = sibling;
 297           sibling->prev = node;
 298         }
 299     }
 300   else
 301     {
 302       if (parent->children)
 303         {
 304           sibling = parent->children;
 305           while (sibling->next)
 306             sibling = sibling->next;
 307           node->prev = sibling;
 308           sibling->next = node;
 309         }
 310       else
 311         node->parent->children = node;
 312     }
 313
 314   return node;
 315 }
 316
 317 GNode*
 318 g_node_insert_after (GNode *parent,
 319                      GNode *sibling,
 320                      GNode *node)
 321 {
 322   g_return_val_if_fail (parent != NULL, node);
 323   g_return_val_if_fail (node != NULL, node);
 324   g_return_val_if_fail (G_NODE_IS_ROOT (node), node);
 325   if (sibling)
 326     g_return_val_if_fail (sibling->parent == parent, node);
 327
 328   node->parent = parent;
 329
 330   if (sibling)
 331     {
 332       if (sibling->next)
 333         {
 334           sibling->next->prev = node;
 335         }
 336       node->next = sibling->next;
 337       node->prev = sibling;
 338       sibling->next = node;
 339     }
 340   else
 341     {
 342       if (parent->children)
 343         {
 344           node->next = parent->children;
 345           parent->children->prev = node;
 346         }
 347       parent->children = node;
 348     }
 349
 350   return node;
 351 }
 352
 353 GNode*
 354 g_node_prepend (GNode *parent,
 355                 GNode *node)
 356 {
 357   g_return_val_if_fail (parent != NULL, node);
 358
 359   return g_node_insert_before (parent, parent->children, node);
 360 }
 361
 362 GNode*
 363 g_node_get_root (GNode *node)
 364 {
 365   g_return_val_if_fail (node != NULL, NULL);
 366
 367   while (node->parent)
 368     node = node->parent;
 369
 370   return node;
 371 }
 372
 373 gboolean
 374 g_node_is_ancestor (GNode *node,
 375                     GNode *descendant)
 376 {
 377   g_return_val_if_fail (node != NULL, FALSE);
 378   g_return_val_if_fail (descendant != NULL, FALSE);
 379
 380   while (descendant)
 381     {
 382       if (descendant->parent == node)
 383         return TRUE;
 384
 385       descendant = descendant->parent;
 386     }
 387
 388   return FALSE;
 389 }
 390
 391 /* returns 1 for root, 2 for first level children,
 392  * 3 for children's children...
 393  */
 394 guint
 395 g_node_depth (GNode *node)
 396 {
 397   register guint depth = 0;
 398
 399   while (node)
 400     {
 401       depth++;
 402       node = node->parent;
 403     }
 404
 405   return depth;
 406 }
 407
 408 void
 409 g_node_reverse_children (GNode *node)
 410 {
 411   GNode *child;
 412   GNode *last;
 413
 414   g_return_if_fail (node != NULL);
 415
 416   child = node->children;
 417   last = NULL;
 418   while (child)
 419     {
 420       last = child;
 421       child = last->next;
 422       last->next = last->prev;
 423       last->prev = child;
 424     }
 425   node->children = last;
 426 }
 427
 428 guint
 429 g_node_max_height (GNode *root)
 430 {
 431   register GNode *child;
 432   register guint max_height = 0;
 433
 434   if (!root)
 435     return 0;
 436
 437   child = root->children;
 438   while (child)
 439     {
 440       register guint tmp_height;
 441
 442       tmp_height = g_node_max_height (child);
 443       if (tmp_height > max_height)
 444         max_height = tmp_height;
 445       child = child->next;
 446     }
 447
 448   return max_height + 1;
 449 }
 450
 451 static gboolean
 452 g_node_traverse_pre_order (GNode            *node,
 453                            GTraverseFlags    flags,
 454                            GNodeTraverseFunc func,
 455                            gpointer          data)
 456 {
 457   if (node->children)
 458     {
 459       GNode *child;
 460
 461       if ((flags & G_TRAVERSE_NON_LEAFS) &&
 462           func (node, data))
 463         return TRUE;
 464
 465       child = node->children;
 466       while (child)
 467         {
 468           register GNode *current;
 469
 470           current = child;
 471           child = current->next;
 472           if (g_node_traverse_pre_order (current, flags, func, data))
 473             return TRUE;
 474         }
 475     }
 476   else if ((flags & G_TRAVERSE_LEAFS) &&
 477            func (node, data))
 478     return TRUE;
 479
 480   return FALSE;
 481 }
 482
 483 static gboolean
 484 g_node_depth_traverse_pre_order (GNode            *node,
 485                                  GTraverseFlags    flags,
 486                                  guint             depth,
 487                                  GNodeTraverseFunc func,
 488                                  gpointer          data)
 489 {
 490   if (node->children)
 491     {
 492       GNode *child;
 493
 494       if ((flags & G_TRAVERSE_NON_LEAFS) &&
 495           func (node, data))
 496         return TRUE;
 497
 498       depth--;
 499       if (!depth)
 500         return FALSE;
 501
 502       child = node->children;
 503       while (child)
 504         {
 505           register GNode *current;
 506
 507           current = child;
 508           child = current->next;
 509           if (g_node_depth_traverse_pre_order (current, flags, depth, func, data))
 510             return TRUE;
 511         }
 512     }
 513   else if ((flags & G_TRAVERSE_LEAFS) &&
 514            func (node, data))
 515     return TRUE;
 516
 517   return FALSE;
 518 }
 519
 520 static gboolean
 521 g_node_traverse_post_order (GNode            *node,
 522                             GTraverseFlags    flags,
 523                             GNodeTraverseFunc func,
 524                             gpointer          data)
 525 {
 526   if (node->children)
 527     {
 528       GNode *child;
 529
 530       child = node->children;
 531       while (child)
 532         {
 533           register GNode *current;
 534
 535           current = child;
 536           child = current->next;
 537           if (g_node_traverse_post_order (current, flags, func, data))
 538             return TRUE;
 539         }
 540
 541       if ((flags & G_TRAVERSE_NON_LEAFS) &&
 542           func (node, data))
 543         return TRUE;
 544
 545     }
 546   else if ((flags & G_TRAVERSE_LEAFS) &&
 547            func (node, data))
 548     return TRUE;
 549
 550   return FALSE;
 551 }
 552
 553 static gboolean
 554 g_node_depth_traverse_post_order (GNode            *node,
 555                                   GTraverseFlags    flags,
 556                                   guint             depth,
 557                                   GNodeTraverseFunc func,
 558                                   gpointer          data)
 559 {
 560   if (node->children)
 561     {
 562       depth--;
 563       if (depth)
 564         {
 565           GNode *child;
 566
 567           child = node->children;
 568           while (child)
 569             {
 570               register GNode *current;
 571
 572               current = child;
 573               child = current->next;
 574               if (g_node_depth_traverse_post_order (current, flags, depth, func, data))
 575                 return TRUE;
 576             }
 577         }
 578
 579       if ((flags & G_TRAVERSE_NON_LEAFS) &&
 580           func (node, data))
 581         return TRUE;
 582
 583     }
 584   else if ((flags & G_TRAVERSE_LEAFS) &&
 585            func (node, data))
 586     return TRUE;
 587
 588   return FALSE;
 589 }
 590
 591 static gboolean
 592 g_node_traverse_in_order (GNode            *node,
 593                           GTraverseFlags    flags,
 594                           GNodeTraverseFunc func,
 595                           gpointer          data)
 596 {
 597   if (node->children)
 598     {
 599       GNode *child;
 600       register GNode *current;
 601
 602       child = node->children;
 603       current = child;
 604       child = current->next;
 605
 606       if (g_node_traverse_in_order (current, flags, func, data))
 607         return TRUE;
 608
 609       if ((flags & G_TRAVERSE_NON_LEAFS) &&
 610           func (node, data))
 611         return TRUE;
 612
 613       while (child)
 614         {
 615           current = child;
 616           child = current->next;
 617           if (g_node_traverse_in_order (current, flags, func, data))
 618             return TRUE;
 619         }
 620     }
 621   else if ((flags & G_TRAVERSE_LEAFS) &&
 622            func (node, data))
 623     return TRUE;
 624
 625   return FALSE;
 626 }
 627
 628 static gboolean
 629 g_node_depth_traverse_in_order (GNode            *node,
 630                                 GTraverseFlags    flags,
 631                                 guint             depth,
 632                                 GNodeTraverseFunc func,
 633                                 gpointer          data)
 634 {
 635   if (node->children)
 636     {
 637       depth--;
 638       if (depth)
 639         {
 640           GNode *child;
 641           register GNode *current;
 642
 643           child = node->children;
 644           current = child;
 645           child = current->next;
 646
 647           if (g_node_depth_traverse_in_order (current, flags, depth, func, data))
 648             return TRUE;
 649
 650           if ((flags & G_TRAVERSE_NON_LEAFS) &&
 651               func (node, data))
 652             return TRUE;
 653
 654           while (child)
 655             {
 656               current = child;
 657               child = current->next;
 658               if (g_node_depth_traverse_in_order (current, flags, depth, func, data))
 659                 return TRUE;
 660             }
 661         }
 662       else if ((flags & G_TRAVERSE_NON_LEAFS) &&
 663                func (node, data))
 664         return TRUE;
 665     }
 666   else if ((flags & G_TRAVERSE_LEAFS) &&
 667            func (node, data))
 668     return TRUE;
 669
 670   return FALSE;
 671 }
 672
 673 static gboolean
 674 g_node_traverse_children (GNode             *node,
 675                           GTraverseFlags     flags,
 676                           GNodeTraverseFunc  func,
 677                           gpointer           data)
 678 {
 679   GNode *child;
 680
 681   child = node->children;
 682
 683   while (child)
 684     {
 685       register GNode *current;
 686
 687       current = child;
 688       child = current->next;
 689
 690       if (current->children)
 691         {
 692           if ((flags & G_TRAVERSE_NON_LEAFS) &&
 693               func (current, data))
 694             return TRUE;
 695         }
 696       else if ((flags & G_TRAVERSE_LEAFS) &&
 697                func (current, data))
 698         return TRUE;
 699     }
 700
 701   child = node->children;
 702
 703   while (child)
 704     {
 705       register GNode *current;
 706
 707       current = child;
 708       child = current->next;
 709
 710       if (current->children &&
 711           g_node_traverse_children (current, flags, func, data))
 712         return TRUE;
 713     }
 714
 715   return FALSE;
 716 }
 717
 718 static gboolean
 719 g_node_depth_traverse_children (GNode            *node,
 720                                 GTraverseFlags    flags,
 721                                 guint             depth,
 722                                 GNodeTraverseFunc func,
 723                                 gpointer          data)
 724 {
 725   GNode *child;
 726
 727   child = node->children;
 728
 729   while (child)
 730     {
 731       register GNode *current;
 732
 733       current = child;
 734       child = current->next;
 735
 736       if (current->children)
 737         {
 738           if ((flags & G_TRAVERSE_NON_LEAFS) &&
 739               func (current, data))
 740             return TRUE;
 741         }
 742       else if ((flags & G_TRAVERSE_LEAFS) &&
 743                func (current, data))
 744         return TRUE;
 745     }
 746
 747   depth--;
 748   if (!depth)
 749     return FALSE;
 750
 751   child = node->children;
 752
 753   while (child)
 754     {
 755       register GNode *current;
 756
 757       current = child;
 758       child = current->next;
 759
 760       if (current->children &&
 761           g_node_depth_traverse_children (current, flags, depth, func, data))
 762         return TRUE;
 763     }
 764
 765   return FALSE;
 766 }
 767
 768 void
 769 g_node_traverse (GNode            *root,
 770                  GTraverseType     order,
 771                  GTraverseFlags    flags,
 772                  gint              depth,
 773                  GNodeTraverseFunc func,
 774                  gpointer          data)
 775 {
 776   g_return_if_fail (root != NULL);
 777   g_return_if_fail (func != NULL);
 778   g_return_if_fail (order <= G_LEVEL_ORDER);
 779   g_return_if_fail (flags <= G_TRAVERSE_MASK);
 780   g_return_if_fail (depth == -1 || depth > 0);
 781
 782   switch (order)
 783     {
 784     case G_PRE_ORDER:
 785       if (depth < 0)
 786         g_node_traverse_pre_order (root, flags, func, data);
 787       else
 788         g_node_depth_traverse_pre_order (root, flags, depth, func, data);
 789       break;
 790     case G_POST_ORDER:
 791       if (depth < 0)
 792         g_node_traverse_post_order (root, flags, func, data);
 793       else
 794         g_node_depth_traverse_post_order (root, flags, depth, func, data);
 795       break;
 796     case G_IN_ORDER:
 797       if (depth < 0)
 798         g_node_traverse_in_order (root, flags, func, data);
 799       else
 800         g_node_depth_traverse_in_order (root, flags, depth, func, data);
 801       break;
 802     case G_LEVEL_ORDER:
 803       if (root->children)
 804         {
 805           if (!((flags & G_TRAVERSE_NON_LEAFS) &&
 806                 func (root, data)))
 807             {
 808               if (depth < 0)
 809                 g_node_traverse_children (root, flags, func, data);
 810               else
 811                 {
 812                   depth--;
 813                   if (depth)
 814                     g_node_depth_traverse_children (root, flags, depth, func, data);
 815                 }
 816             }
 817         }
 818       else if (flags & G_TRAVERSE_LEAFS)
 819         func (root, data);
 820       break;
 821     }
 822 }
 823
 824 static gboolean
 825 g_node_find_func (GNode   *node,
 826                   gpointer data)
 827 {
 828   register gpointer *d = data;
 829
 830   if (*d != node->data)
 831     return FALSE;
 832
 833   *(++d) = node;
 834
 835   return TRUE;
 836 }
 837
 838 GNode*
 839 g_node_find (GNode             *root,
 840              GTraverseType      order,
 841              GTraverseFlags     flags,
 842              gpointer           data)
 843 {
 844   gpointer d[2];
 845
 846   g_return_val_if_fail (root != NULL, NULL);
 847   g_return_val_if_fail (order <= G_LEVEL_ORDER, NULL);
 848   g_return_val_if_fail (flags <= G_TRAVERSE_MASK, NULL);
 849
 850   d[0] = data;
 851   d[1] = NULL;
 852
 853   g_node_traverse (root, order, flags, -1, g_node_find_func, d);
 854
 855   return d[1];
 856 }
 857
 858 static void
 859 g_node_count_func (GNode         *node,
 860                    GTraverseFlags flags,
 861                    guint         *n)
 862 {
 863   if (node->children)
 864     {
 865       GNode *child;
 866
 867       if (flags & G_TRAVERSE_NON_LEAFS)
 868         (*n)++;
 869
 870       child = node->children;
 871       while (child)
 872         {
 873           g_node_count_func (child, flags, n);
 874           child = child->next;
 875         }
 876     }
 877   else if (flags & G_TRAVERSE_LEAFS)
 878     (*n)++;
 879 }
 880
 881 guint
 882 g_node_n_nodes (GNode         *root,
 883                 GTraverseFlags flags)
 884 {
 885   guint n = 0;
 886
 887   g_return_val_if_fail (root != NULL, 0);
 888   g_return_val_if_fail (flags <= G_TRAVERSE_MASK, 0);
 889
 890   g_node_count_func (root, flags, &n);
 891
 892   return n;
 893 }
 894
 895 GNode*
 896 g_node_last_child (GNode *node)
 897 {
 898   g_return_val_if_fail (node != NULL, NULL);
 899
 900   node = node->children;
 901   if (node)
 902     while (node->next)
 903       node = node->next;
 904
 905   return node;
 906 }
 907
 908 GNode*
 909 g_node_nth_child (GNode *node,
 910                   guint  n)
 911 {
 912   g_return_val_if_fail (node != NULL, NULL);
 913
 914   node = node->children;
 915   if (node)
 916     while ((n-- > 0) && node)
 917       node = node->next;
 918
 919   return node;
 920 }
 921
 922 guint
 923 g_node_n_children (GNode *node)
 924 {
 925   guint n = 0;
 926
 927   g_return_val_if_fail (node != NULL, 0);
 928
 929   node = node->children;
 930   while (node)
 931     {
 932       n++;
 933       node = node->next;
 934     }
 935
 936   return n;
 937 }
 938
 939 GNode*
 940 g_node_find_child (GNode         *node,
 941                    GTraverseFlags flags,
 942                    gpointer       data)
 943 {
 944   g_return_val_if_fail (node != NULL, NULL);
 945   g_return_val_if_fail (flags <= G_TRAVERSE_MASK, NULL);
 946
 947   node = node->children;
 948   while (node)
 949     {
 950       if (node->data == data)
 951         {
 952           if (G_NODE_IS_LEAF (node))
 953             {
 954               if (flags & G_TRAVERSE_LEAFS)
 955                 return node;
 956             }
 957           else
 958             {
 959               if (flags & G_TRAVERSE_NON_LEAFS)
 960                 return node;
 961             }
 962         }
 963       node = node->next;
 964     }
 965
 966   return NULL;
 967 }
 968
 969 gint
 970 g_node_child_position (GNode *node,
 971                        GNode *child)
 972 {
 973   register guint n = 0;
 974
 975   g_return_val_if_fail (node != NULL, -1);
 976   g_return_val_if_fail (child != NULL, -1);
 977   g_return_val_if_fail (child->parent == node, -1);
 978
 979   node = node->children;
 980   while (node)
 981     {
 982       if (node == child)
 983         return n;
 984       n++;
 985       node = node->next;
 986     }
 987
 988   return -1;
 989 }
 990
 991 gint
 992 g_node_child_index (GNode   *node,
 993                     gpointer data)
 994 {
 995   register guint n = 0;
 996
 997   g_return_val_if_fail (node != NULL, -1);
 998
 999   node = node->children;
1000   while (node)
1001     {
1002       if (node->data == data)
1003         return n;
1004       n++;
1005       node = node->next;
1006     }
1007
1008   return -1;
1009 }
1010
1011 GNode*
1012 g_node_first_sibling (GNode *node)
1013 {
1014   g_return_val_if_fail (node != NULL, NULL);
1015
1016   if (node->parent)
1017     return node->parent->children;
1018
1019   while (node->prev)
1020     node = node->prev;
1021
1022   return node;
1023 }
1024
1025 GNode*
1026 g_node_last_sibling (GNode *node)
1027 {
1028   g_return_val_if_fail (node != NULL, NULL);
1029
1030   while (node->next)
1031     node = node->next;
1032
1033   return node;
1034 }
1035
1036 void
1037 g_node_children_foreach (GNode           *node,
1038                          GTraverseFlags   flags,
1039                          GNodeForeachFunc func,
1040                          gpointer         data)
1041 {
1042   g_return_if_fail (node != NULL);
1043   g_return_if_fail (flags <= G_TRAVERSE_MASK);
1044   g_return_if_fail (func != NULL);
1045
1046   node = node->children;
1047   while (node)
1048     {
1049       register GNode *current;
1050
1051       current = node;
1052       node = current->next;
1053       if (G_NODE_IS_LEAF (current))
1054         {
1055           if (flags & G_TRAVERSE_LEAFS)
1056             func (current, data);
1057         }
1058       else
1059         {
1060           if (flags & G_TRAVERSE_NON_LEAFS)
1061             func (current, data);
1062         }
1063     }
1064 }