pdf_name_tree.c

Fri, 14 Mar 2003 07:08:52 +0000

author
eric
date
Fri, 14 Mar 2003 07:08:52 +0000
changeset 130
d47b66e1722f
parent 125
e2ef1c2f9eca
child 131
4b8c80d77f76
permissions
-rw-r--r--

bookmarks should only be created for first page in a group.

     1 /*
     2  * tumble: build a PDF file from image files
     3  *
     4  * PDF routines
     5  * $Id: pdf_name_tree.c,v 1.9 2003/03/13 00:57:05 eric Exp $
     6  * Copyright 2003 Eric Smith <eric@brouhaha.com>
     7  *
     8  * This program is free software; you can redistribute it and/or modify
     9  * it under the terms of the GNU General Public License version 2 as
    10  * published by the Free Software Foundation.  Note that permission is
    11  * not granted to redistribute this program under the terms of any
    12  * other version of the General Public License.
    13  *
    14  * This program is distributed in the hope that it will be useful,
    15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
    16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    17  * GNU General Public License for more details.
    18  *
    19  * You should have received a copy of the GNU General Public License
    20  * along with this program; if not, write to the Free Software
    21  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111 USA
    22  */
    25 #include <stdbool.h>
    26 #include <stdint.h>
    27 #include <stdio.h>
    28 #include <stdlib.h>
    29 #include <string.h>
    32 #include "bitblt.h"
    33 #include "pdf.h"
    34 #include "pdf_util.h"
    35 #include "pdf_prim.h"
    36 #include "pdf_private.h"
    37 #include "pdf_name_tree.h"
    40 #define MAX_NAME_TREE_NODE_ENTRIES 16
    43 struct pdf_name_tree_node
    44 {
    45   struct pdf_obj *dict;    /* indirect reference */
    47   struct pdf_name_tree_node *parent;  /* NULL for root */
    48   bool leaf;
    50   int count;               /* how many kids or names/numbers are
    51 			      attached to this node */
    53   struct pdf_name_tree_node *kids [MAX_NAME_TREE_NODE_ENTRIES];  /* non-leaf only */
    55   struct pdf_obj *min_key;
    56   struct pdf_obj *max_key;
    58   /* following fields valid in leaf nodes only: */
    60   struct pdf_obj *keys [MAX_NAME_TREE_NODE_ENTRIES];
    61   struct pdf_obj *values [MAX_NAME_TREE_NODE_ENTRIES];
    62 };
    65 struct pdf_name_tree *pdf_new_name_tree (pdf_file_handle pdf_file,
    66 					 bool number_tree)
    67 {
    68   struct pdf_name_tree *tree;
    69   struct pdf_name_tree_node *root;
    71   root = pdf_calloc (1, sizeof (struct pdf_name_tree_node));
    72   tree = pdf_calloc (1, sizeof (struct pdf_name_tree));
    74   tree->pdf_file = pdf_file;
    75   tree->root = root;
    76   tree->number_tree = number_tree;
    78   root->parent = NULL;
    79   root->leaf = 1;
    81   tree->next = pdf_file->name_tree_list;
    82   pdf_file->name_tree_list = tree;
    84   return (tree);
    85 }
    88 static void pdf_split_name_tree_node (struct pdf_name_tree *tree,
    89 				      struct pdf_name_tree_node *node)
    90 {
    91   struct pdf_name_tree_node *parent;
    92   struct pdf_name_tree_node *new_node;
    93   int i, j;
    95   parent = node->parent;
    96   if (! parent)
    97     {
    98       /* create new root above current root */
    99       struct pdf_name_tree_node *new_root_node;
   101       new_root_node = pdf_calloc (1, sizeof (struct pdf_name_tree_node));
   103       new_root_node->parent = NULL;
   104       new_root_node->leaf = 0;
   106       new_root_node->count = 1;
   107       new_root_node->kids [0] = node;
   109       new_root_node->min_key = node->min_key;
   110       new_root_node->max_key = node->max_key;
   112       parent = new_root_node;
   113       node->parent = new_root_node;
   114       tree->root = new_root_node;
   115     }
   117   if (parent->count == MAX_NAME_TREE_NODE_ENTRIES)
   118     {
   119       pdf_split_name_tree_node (tree, parent);
   120       parent = node->parent;
   121     }
   123   new_node = pdf_calloc (1, sizeof (struct pdf_name_tree_node));
   124   new_node->parent = parent;
   125   new_node->leaf = node->leaf;
   127   /* move half the node's entries into the new node */
   128   i = node->count / 2;
   129   j = node->count - i;
   131   memcpy (& new_node->kids [0],
   132 	  & node->kids [i],
   133 	  j * sizeof (struct pdf_name_tree_node *));
   134   memcpy (& new_node->keys [0],
   135 	  & node->keys [i],
   136 	  j * sizeof (struct pdf_obj *));
   137   memcpy (& new_node->values [0],
   138 	  & node->values [i],
   139 	  j * sizeof (struct pdf_obj *));
   141   node->count = i;
   142   new_node->count = j;
   144   if (! new_node->leaf)
   145     for (i = 0; i < j; i++)
   146       new_node->kids [i]->parent = new_node;
   148   /* set max_key of the old node */
   149   if (node->leaf)
   150     node->max_key = node->keys [node->count - 1];
   151   else
   152     node->max_key = node->kids [node->count - 1]->max_key;
   154   /* set min_key and max_key in the new node */
   155   if (new_node->leaf)
   156     {
   157       new_node->min_key = new_node->keys [0];
   158       new_node->max_key = new_node->keys [new_node->count - 1];
   159     }
   160   else
   161     {
   162       new_node->min_key = new_node->kids [0]->min_key;
   163       new_node->max_key = new_node->kids [new_node->count - 1]->max_key;
   164     }
   166   /* insert new node in parent's kids array */
   167   /* find entry of old node */
   168   for (i = 0; i < parent->count; i++)
   169     if (parent->kids [i] == node)
   170       break;
   172   /* it had better have been there! */
   173   pdf_assert (i < parent->count);
   175   /* the new node goes in the slot to the right of the old node */
   176   i++;
   178   /* move other entries right one position */
   179   if (i != parent->count)
   180     {
   181       memmove (& parent->kids [i+1],
   182 	       & parent->kids [i],
   183 	       (parent->count - i) * sizeof (struct pdf_name_tree_node *));
   184     }
   186   parent->kids [i] = new_node;
   187   parent->count++;
   188 }
   191 static void pdf_add_tree_element (struct pdf_name_tree *tree,
   192 				  struct pdf_obj *key,
   193 				  struct pdf_obj *val)
   194 {
   195   struct pdf_name_tree_node *node;
   196   int i;
   198   /* find node which should contain element */
   199   node = tree->root;
   200   while (! node->leaf)
   201     {
   202       for (i = 0; i < (node->count - 1); i++)
   203 	if (pdf_compare_obj (key, node->kids [i + 1]->min_key) < 0)
   204 	  break;
   205       node = node->kids [i];
   206     }
   208   /* if node is full, split, recursing to root if necessary */
   209   if (node->count == MAX_NAME_TREE_NODE_ENTRIES)
   210     {
   211       pdf_split_name_tree_node (tree, node);
   212       pdf_add_tree_element (tree, key, val);
   213       return;
   214     }
   216   /* figure out in which slot to insert it */
   217   for (i = 0; i < node->count; i++)
   218     if (pdf_compare_obj (key, node->keys [i]) < 0)
   219       break;
   221   /* move other entries right one position */
   222   if (i != node->count)
   223     {
   224       memmove (& node->keys [i+1],
   225 	       & node->keys [i],
   226 	       (node->count - i) * sizeof (struct pdf_obj *));
   227       memmove (& node->values [i+1],
   228 	       & node->values [i],
   229 	       (node->count - i) * sizeof (struct pdf_obj *));
   230     }
   232   node->keys [i] = key;
   233   node->values [i] = val;
   235   node->count++;
   237   /* update limits, recursing upwards if necessary */
   238   if (i == 0)
   239     {
   240       node->min_key = key;
   241       while (node->parent && (node->parent->kids [0] == node))
   242 	{
   243 	  node = node->parent;
   244 	  node->min_key = key;
   245 	}
   246     }
   247   if (i == (node->count - 1))
   248     {
   249       node->max_key = key;
   250       while (node->parent && (node->parent->kids [node->parent->count - 1] == node))
   251 	{
   252 	  node = node->parent;
   253 	  node->max_key = key;
   254 	}
   255     }
   256 }
   259 void pdf_add_name_tree_element (struct pdf_name_tree *tree,
   260 				char *key,
   261 				struct pdf_obj *val)
   262 {
   263   struct pdf_obj *key_obj = pdf_new_string (key);
   264   pdf_add_tree_element (tree, key_obj, val);
   265 }
   268 void pdf_add_number_tree_element (struct pdf_name_tree *tree,
   269 				  long key,
   270 				  struct pdf_obj *val)
   271 {
   272   struct pdf_obj *key_obj = pdf_new_integer (key);
   273   pdf_add_tree_element (tree, key_obj, val);
   274 }
   277 static void pdf_finalize_name_tree_node (struct pdf_name_tree *tree,
   278 					 struct pdf_name_tree_node *node)
   279 {
   280   int i;
   282   node->dict = pdf_new_ind_ref (tree->pdf_file, pdf_new_obj (PT_DICTIONARY));
   284   if (node->leaf)
   285     {
   286       /* write Names or Nums array */
   287       struct pdf_obj *names = pdf_new_obj (PT_ARRAY);
   288       for (i = 0; i < node->count; i++)
   289 	{
   290 	  pdf_add_array_elem (names, node->keys [i]);
   291 	  pdf_add_array_elem (names, node->values [i]);
   292 	}
   293       pdf_set_dict_entry (node->dict,
   294 			  tree->number_tree ? "Nums" : "Names",
   295 			  names);
   296     }
   297   else
   298     {
   299       /* finalize the children first so that their dict ind ref is
   300 	 available */
   301       struct pdf_obj *kids;
   303       for (i = 0; i < node->count; i++)
   304 	pdf_finalize_name_tree_node (tree, node->kids [i]);
   306       /* write Kids array */
   307       kids = pdf_new_obj (PT_ARRAY);
   308       for (i = 0; i < node->count; i++)
   309 	pdf_add_array_elem (kids, node->kids [i]->dict);
   310       pdf_set_dict_entry (node->dict, "Kids", kids);
   311     }
   313   if (node->parent)
   314     {
   315       /* write Limits array */
   316       struct pdf_obj *limits = pdf_new_obj (PT_ARRAY);
   317       pdf_add_array_elem (limits, node->min_key);
   318       pdf_add_array_elem (limits, node->max_key);
   319       pdf_set_dict_entry (node->dict, "Limits", limits);
   320     }
   321 }
   324 void pdf_finalize_name_trees (pdf_file_handle pdf_file)
   325 {
   326   struct pdf_name_tree *tree;
   328   for (tree = pdf_file->name_tree_list; tree; tree = tree->next)
   329     pdf_finalize_name_tree_node (tree, tree->root);
   330 }