Fri, 07 Mar 2003 11:35:36 +0000
more work on pdf_add_tree_element().
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 1.3 2003/03/07 03:35:36 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 return (tree);
84 }
87 static void pdf_split_name_tree_node (struct pdf_name_tree *tree,
88 struct pdf_name_tree_node *node)
89 {
90 struct pdf_name_tree_node *new_node;
92 if (node == tree->root)
93 {
94 /* create new root above current root */
95 struct pdf_name_tree_node *new_root_node;
97 new_root_node = pdf_calloc (1, sizeof (struct pdf_name_tree_node));
99 new_root_node->parent = NULL;
100 new_root_node->leaf = 0;
102 new_root_node->count = 1;
103 new_root_node->kids [0] = node;
105 new_root_node->min_key = node->min_key;
106 new_root_node->max_key = node->max_key;
108 node->parent = new_root_node;
109 tree->root = new_root_node;
110 }
112 new_node = pdf_calloc (1, sizeof (struct pdf_name_tree_node));
113 new_node->parent = node->parent;
114 new_node->leaf = node->leaf;
116 /* $$$ insert new node in parent's kids array */
117 }
120 static void pdf_add_tree_element (struct pdf_name_tree *tree,
121 struct pdf_obj *key,
122 struct pdf_obj *val)
123 {
124 struct pdf_name_tree_node *node;
125 int i;
127 /* find node which should contain element */
128 node = tree->root;
129 while (! node->leaf)
130 {
131 for (i = 0; i < (node->count - 1); i++)
132 if (pdf_compare_obj (key, node->kids [i + 1]->min_key) < 0)
133 break;
134 node = node->kids [i];
135 }
137 /* if node is full, split, recursing to root if necessary */
138 if (node->count == MAX_NAME_TREE_NODE_ENTRIES)
139 {
140 pdf_split_name_tree_node (tree, node);
141 pdf_add_tree_element (tree, key, val);
142 return;
143 }
145 /* figure out in which slot to insert it */
146 for (i = 0; i < node->count; i++)
147 if (pdf_compare_obj (key, node->keys [i] < 0))
148 break;
150 /* move other entries right one position */
151 if (i != node->count)
152 {
153 memmove (& node->keys [i+1],
154 & node->keys [i],
155 (node->count - i) * sizeof (struct pdf_obj *));
156 memmove (& node->values [i+1],
157 & node->values [i],
158 (node->count - i) * sizeof (struct pdf_obj *));
159 }
161 node->keys [i] = key;
162 node->values [i] = val;
164 node->count++;
166 /* update limits, recursing upwards if necessary */
167 if (i == 0)
168 {
169 node->min_key = key;
170 while (node->parent && (node->parent->kids [0] == node))
171 {
172 node = node->parent;
173 node->min_key = key;
174 }
175 }
176 else if (i == (node->count - 1))
177 {
178 node->max_key = key;
179 while (node->parent && (node->parent->kids [node->parent->count - 1] == node))
180 {
181 node = node->parent;
182 node->max_key = key;
183 }
184 }
185 }
188 void pdf_add_name_tree_element (struct pdf_name_tree *tree,
189 char *key,
190 struct pdf_obj *val)
191 {
192 struct pdf_obj *key_obj = pdf_new_string (key);
193 pdf_add_tree_element (tree, key_obj, val);
194 }
197 void pdf_add_number_tree_element (struct pdf_name_tree *tree,
198 long key,
199 struct pdf_obj *val)
200 {
201 struct pdf_obj *key_obj = pdf_new_integer (key);
202 pdf_add_tree_element (tree, key_obj, val);
203 }
206 static void pdf_finalize_name_tree_node (struct pdf_name_tree *tree,
207 struct pdf_name_tree_node *node)
208 {
209 int i;
211 node->dict = pdf_new_ind_ref (tree->pdf_file, pdf_new_obj (PT_DICTIONARY));
213 if (node->leaf)
214 {
215 /* write Names or Nums array */
216 struct pdf_obj *names = pdf_new_obj (PT_ARRAY);
217 for (i = 0; i < node->count; i++)
218 {
219 pdf_add_array_elem (names, node->keys [i]);
220 pdf_add_array_elem (names, node->values [i]);
221 }
222 pdf_set_dict_entry (node->dict,
223 tree->number_tree ? "Nums" : "Names",
224 names);
225 }
226 else
227 {
228 /* finalize the children first so that their dict ind ref is
229 available */
230 for (i = 0; i < node->count; i++)
231 pdf_finalize_name_tree_node (tree, node->kids [i]);
233 /* write Kids array */
234 struct pdf_obj *kids = pdf_new_obj (PT_ARRAY);
235 for (i = 0; i < node->count; i++)
236 pdf_add_array_elem (kids, node->kids [i]->dict);
237 pdf_set_dict_entry (node->dict, "Kids", kids);
238 }
240 if (! node->parent)
241 {
242 /* write Limits array */
243 struct pdf_obj *limits = pdf_new_obj (PT_ARRAY);
244 pdf_add_array_elem (limits, node->min_key);
245 pdf_add_array_elem (limits, node->max_key);
246 pdf_set_dict_entry (node->dict, "Limits", limits);
247 }
248 }
251 void pdf_finalize_name_tree (struct pdf_name_tree *tree)
252 {
253 pdf_finalize_name_tree_node (tree, tree->root);
254 }