pdf_name_tree.c

Sat, 08 Mar 2003 06:52:09 +0000

author
eric
date
Sat, 08 Mar 2003 06:52:09 +0000
changeset 85
dcfd1d4b5c24
parent 84
a54eb7b9fc15
child 87
870a093b587c
permissions
-rw-r--r--

add linked list of name trees to struct pdf_file, and finalize all name trees when PDF file is closed.

     1 /*
     2  * t2p: Create a PDF file from the contents of one or more TIFF
     3  *      bilevel image files.  The images in the resulting PDF file
     4  *      will be compressed using ITU-T T.6 (G4) fax encoding.
     5  *
     6  * PDF routines
     7  * $Id: pdf_name_tree.c,v 1.4 2003/03/07 22:52:09 eric Exp $
     8  * Copyright 2003 Eric Smith <eric@brouhaha.com>
     9  *
    10  * This program is free software; you can redistribute it and/or modify
    11  * it under the terms of the GNU General Public License version 2 as
    12  * published by the Free Software Foundation.  Note that permission is
    13  * not granted to redistribute this program under the terms of any
    14  * other version of the General Public License.
    15  *
    16  * This program is distributed in the hope that it will be useful,
    17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
    18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    19  * GNU General Public License for more details.
    20  *
    21  * You should have received a copy of the GNU General Public License
    22  * along with this program; if not, write to the Free Software
    23  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111 USA
    24  */
    27 #include <stdbool.h>
    28 #include <stdint.h>
    29 #include <stdio.h>
    30 #include <stdlib.h>
    31 #include <string.h>
    34 #include "bitblt.h"
    35 #include "pdf.h"
    36 #include "pdf_util.h"
    37 #include "pdf_prim.h"
    38 #include "pdf_private.h"
    39 #include "pdf_name_tree.h"
    42 #define MAX_NAME_TREE_NODE_ENTRIES 16
    45 struct pdf_name_tree_node
    46 {
    47   struct pdf_obj *dict;    /* indirect reference */
    49   struct pdf_name_tree_node *parent;  /* NULL for root */
    50   bool leaf;
    52   int count;               /* how many kids or names/numbers are
    53 			      attached to this node */
    55   struct pdf_name_tree_node *kids [MAX_NAME_TREE_NODE_ENTRIES];  /* non-leaf only */
    57   struct pdf_obj *min_key;
    58   struct pdf_obj *max_key;
    60   /* following fields valid in leaf nodes only: */
    62   struct pdf_obj *keys [MAX_NAME_TREE_NODE_ENTRIES];
    63   struct pdf_obj *values [MAX_NAME_TREE_NODE_ENTRIES];
    64 };
    67 struct pdf_name_tree *pdf_new_name_tree (pdf_file_handle pdf_file,
    68 					 bool number_tree)
    69 {
    70   struct pdf_name_tree *tree;
    71   struct pdf_name_tree_node *root;
    73   root = pdf_calloc (1, sizeof (struct pdf_name_tree_node));
    74   tree = pdf_calloc (1, sizeof (struct pdf_name_tree));
    76   tree->pdf_file = pdf_file;
    77   tree->root = root;
    78   tree->number_tree = number_tree;
    80   root->parent = NULL;
    81   root->leaf = 1;
    83   tree->next = pdf_file->name_tree_list;
    84   pdf_file->name_tree_list = tree;
    86   return (tree);
    87 }
    90 static void pdf_split_name_tree_node (struct pdf_name_tree *tree,
    91 				      struct pdf_name_tree_node *node)
    92 {
    93   struct pdf_name_tree_node *new_node;
    95   if (node == tree->root)
    96     {
    97       /* create new root above current root */
    98       struct pdf_name_tree_node *new_root_node;
   100       new_root_node = pdf_calloc (1, sizeof (struct pdf_name_tree_node));
   102       new_root_node->parent = NULL;
   103       new_root_node->leaf = 0;
   105       new_root_node->count = 1;
   106       new_root_node->kids [0] = node;
   108       new_root_node->min_key = node->min_key;
   109       new_root_node->max_key = node->max_key;
   111       node->parent = new_root_node;
   112       tree->root = new_root_node;
   113     }
   115   new_node = pdf_calloc (1, sizeof (struct pdf_name_tree_node));
   116   new_node->parent = node->parent;
   117   new_node->leaf = node->leaf;
   119   /* $$$ insert new node in parent's kids array */
   120 }
   123 static void pdf_add_tree_element (struct pdf_name_tree *tree,
   124 				  struct pdf_obj *key,
   125 				  struct pdf_obj *val)
   126 {
   127   struct pdf_name_tree_node *node;
   128   int i;
   130   /* find node which should contain element */
   131   node = tree->root;
   132   while (! node->leaf)
   133     {
   134       for (i = 0; i < (node->count - 1); i++)
   135 	if (pdf_compare_obj (key, node->kids [i + 1]->min_key) < 0)
   136 	  break;
   137       node = node->kids [i];
   138     }
   140   /* if node is full, split, recursing to root if necessary */
   141   if (node->count == MAX_NAME_TREE_NODE_ENTRIES)
   142     {
   143       pdf_split_name_tree_node (tree, node);
   144       pdf_add_tree_element (tree, key, val);
   145       return;
   146     }
   148   /* figure out in which slot to insert it */
   149   for (i = 0; i < node->count; i++)
   150     if (pdf_compare_obj (key, node->keys [i] < 0))
   151       break;
   153   /* move other entries right one position */
   154   if (i != node->count)
   155     {
   156       memmove (& node->keys [i+1],
   157 	       & node->keys [i],
   158 	       (node->count - i) * sizeof (struct pdf_obj *));
   159       memmove (& node->values [i+1],
   160 	       & node->values [i],
   161 	       (node->count - i) * sizeof (struct pdf_obj *));
   162     }
   164   node->keys [i] = key;
   165   node->values [i] = val;
   167   node->count++;
   169   /* update limits, recursing upwards if necessary */
   170   if (i == 0)
   171     {
   172       node->min_key = key;
   173       while (node->parent && (node->parent->kids [0] == node))
   174 	{
   175 	  node = node->parent;
   176 	  node->min_key = key;
   177 	}
   178     }
   179   else if (i == (node->count - 1))
   180     {
   181       node->max_key = key;
   182       while (node->parent && (node->parent->kids [node->parent->count - 1] == node))
   183 	{
   184 	  node = node->parent;
   185 	  node->max_key = key;
   186 	}
   187     }
   188 }
   191 void pdf_add_name_tree_element (struct pdf_name_tree *tree,
   192 				char *key,
   193 				struct pdf_obj *val)
   194 {
   195   struct pdf_obj *key_obj = pdf_new_string (key);
   196   pdf_add_tree_element (tree, key_obj, val);
   197 }
   200 void pdf_add_number_tree_element (struct pdf_name_tree *tree,
   201 				  long key,
   202 				  struct pdf_obj *val)
   203 {
   204   struct pdf_obj *key_obj = pdf_new_integer (key);
   205   pdf_add_tree_element (tree, key_obj, val);
   206 }
   209 static void pdf_finalize_name_tree_node (struct pdf_name_tree *tree,
   210 					 struct pdf_name_tree_node *node)
   211 {
   212   int i;
   214   node->dict = pdf_new_ind_ref (tree->pdf_file, pdf_new_obj (PT_DICTIONARY));
   216   if (node->leaf)
   217     {
   218       /* write Names or Nums array */
   219       struct pdf_obj *names = pdf_new_obj (PT_ARRAY);
   220       for (i = 0; i < node->count; i++)
   221 	{
   222 	  pdf_add_array_elem (names, node->keys [i]);
   223 	  pdf_add_array_elem (names, node->values [i]);
   224 	}
   225       pdf_set_dict_entry (node->dict,
   226 			  tree->number_tree ? "Nums" : "Names",
   227 			  names);
   228     }
   229   else
   230     {
   231       /* finalize the children first so that their dict ind ref is
   232 	 available */
   233       for (i = 0; i < node->count; i++)
   234 	pdf_finalize_name_tree_node (tree, node->kids [i]);
   236       /* write Kids array */
   237       struct pdf_obj *kids = pdf_new_obj (PT_ARRAY);
   238       for (i = 0; i < node->count; i++)
   239 	pdf_add_array_elem (kids, node->kids [i]->dict);
   240       pdf_set_dict_entry (node->dict, "Kids", kids);
   241     }
   243   if (! node->parent)
   244     {
   245       /* write Limits array */
   246       struct pdf_obj *limits = pdf_new_obj (PT_ARRAY);
   247       pdf_add_array_elem (limits, node->min_key);
   248       pdf_add_array_elem (limits, node->max_key);
   249       pdf_set_dict_entry (node->dict, "Limits", limits);
   250     }
   251 }
   254 void pdf_finalize_name_trees (pdf_file_handle pdf_file)
   255 {
   256   struct pdf_name_tree *tree;
   258   for (tree = pdf_file->name_tree_list; tree; tree = tree->next)
   259     pdf_finalize_name_tree_node (tree, tree->root);
   260 }