Sat, 08 Mar 2003 09:23:05 +0000
fix bugs in pdf_split_name_tree_node().
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 1.6 2003/03/08 01:23:05 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 *parent;
94 struct pdf_name_tree_node *new_node;
95 int i, j;
97 parent = node->parent;
98 if (! parent)
99 {
100 /* create new root above current root */
101 struct pdf_name_tree_node *new_root_node;
103 new_root_node = pdf_calloc (1, sizeof (struct pdf_name_tree_node));
105 new_root_node->parent = NULL;
106 new_root_node->leaf = 0;
108 new_root_node->count = 1;
109 new_root_node->kids [0] = node;
111 new_root_node->min_key = node->min_key;
112 new_root_node->max_key = node->max_key;
114 parent = new_root_node;
115 node->parent = new_root_node;
116 tree->root = new_root_node;
117 }
119 new_node = pdf_calloc (1, sizeof (struct pdf_name_tree_node));
120 new_node->parent = parent;
121 new_node->leaf = node->leaf;
123 /* move half the node's entries into the new node */
124 i = node->count / 2;
125 j = node->count - i;
127 memcpy (& new_node->kids [0],
128 & node->kids [i],
129 j * sizeof (struct pdf_name_tree_node *));
130 memcpy (& new_node->keys [0],
131 & node->keys [i],
132 j * sizeof (struct pdf_obj *));
133 memcpy (& new_node->values [0],
134 & node->values [i],
135 j * sizeof (struct pdf_obj *));
136 node->count = i;
137 new_node->count = j;
139 /* set max_key of the old node */
140 if (node->leaf)
141 node->max_key = node->keys [node->count - 1];
142 else
143 node->max_key = node->kids [node->count - 1]->max_key;
145 /* set min_key and max_key in the new node */
146 if (new_node->leaf)
147 {
148 new_node->min_key = new_node->keys [0];
149 new_node->max_key = new_node->keys [new_node->count - 1];
150 }
151 else
152 {
153 new_node->min_key = new_node->kids [0]->min_key;
154 new_node->max_key = new_node->kids [new_node->count - 1]->max_key;
155 }
157 /* insert new node in parent's kids array */
158 /* find entry of old node */
159 for (i = 0; i < parent->count; i++)
160 if (parent->kids [i] == node)
161 break;
163 /* it had better have been there! */
164 pdf_assert (i < parent->count);
166 /* the new node goes in the slot to the right of the old node */
167 i++;
169 /* move other entries right one position */
170 if (i != parent->count)
171 {
172 memmove (& parent->kids [i+1],
173 & parent->kids [i],
174 (parent->count - i) * sizeof (struct pdf_name_tree_node *));
175 }
177 parent->kids [i] = new_node;
178 parent->count++;
179 }
182 static void pdf_add_tree_element (struct pdf_name_tree *tree,
183 struct pdf_obj *key,
184 struct pdf_obj *val)
185 {
186 struct pdf_name_tree_node *node;
187 int i;
189 /* find node which should contain element */
190 node = tree->root;
191 while (! node->leaf)
192 {
193 for (i = 0; i < (node->count - 1); i++)
194 if (pdf_compare_obj (key, node->kids [i + 1]->min_key) < 0)
195 break;
196 node = node->kids [i];
197 }
199 /* if node is full, split, recursing to root if necessary */
200 if (node->count == MAX_NAME_TREE_NODE_ENTRIES)
201 {
202 pdf_split_name_tree_node (tree, node);
203 pdf_add_tree_element (tree, key, val);
204 return;
205 }
207 /* figure out in which slot to insert it */
208 for (i = 0; i < node->count; i++)
209 if (pdf_compare_obj (key, node->keys [i]) < 0)
210 break;
212 /* move other entries right one position */
213 if (i != node->count)
214 {
215 memmove (& node->keys [i+1],
216 & node->keys [i],
217 (node->count - i) * sizeof (struct pdf_obj *));
218 memmove (& node->values [i+1],
219 & node->values [i],
220 (node->count - i) * sizeof (struct pdf_obj *));
221 }
223 node->keys [i] = key;
224 node->values [i] = val;
226 node->count++;
228 /* update limits, recursing upwards if necessary */
229 if (i == 0)
230 {
231 node->min_key = key;
232 while (node->parent && (node->parent->kids [0] == node))
233 {
234 node = node->parent;
235 node->min_key = key;
236 }
237 }
238 if (i == (node->count - 1))
239 {
240 node->max_key = key;
241 while (node->parent && (node->parent->kids [node->parent->count - 1] == node))
242 {
243 node = node->parent;
244 node->max_key = key;
245 }
246 }
247 }
250 void pdf_add_name_tree_element (struct pdf_name_tree *tree,
251 char *key,
252 struct pdf_obj *val)
253 {
254 struct pdf_obj *key_obj = pdf_new_string (key);
255 pdf_add_tree_element (tree, key_obj, val);
256 }
259 void pdf_add_number_tree_element (struct pdf_name_tree *tree,
260 long key,
261 struct pdf_obj *val)
262 {
263 struct pdf_obj *key_obj = pdf_new_integer (key);
264 pdf_add_tree_element (tree, key_obj, val);
265 }
268 static void pdf_finalize_name_tree_node (struct pdf_name_tree *tree,
269 struct pdf_name_tree_node *node)
270 {
271 int i;
273 node->dict = pdf_new_ind_ref (tree->pdf_file, pdf_new_obj (PT_DICTIONARY));
275 if (node->leaf)
276 {
277 /* write Names or Nums array */
278 struct pdf_obj *names = pdf_new_obj (PT_ARRAY);
279 for (i = 0; i < node->count; i++)
280 {
281 pdf_add_array_elem (names, node->keys [i]);
282 pdf_add_array_elem (names, node->values [i]);
283 }
284 pdf_set_dict_entry (node->dict,
285 tree->number_tree ? "Nums" : "Names",
286 names);
287 }
288 else
289 {
290 /* finalize the children first so that their dict ind ref is
291 available */
292 for (i = 0; i < node->count; i++)
293 pdf_finalize_name_tree_node (tree, node->kids [i]);
295 /* write Kids array */
296 struct pdf_obj *kids = pdf_new_obj (PT_ARRAY);
297 for (i = 0; i < node->count; i++)
298 pdf_add_array_elem (kids, node->kids [i]->dict);
299 pdf_set_dict_entry (node->dict, "Kids", kids);
300 }
302 if (node->parent)
303 {
304 /* write Limits array */
305 struct pdf_obj *limits = pdf_new_obj (PT_ARRAY);
306 pdf_add_array_elem (limits, node->min_key);
307 pdf_add_array_elem (limits, node->max_key);
308 pdf_set_dict_entry (node->dict, "Limits", limits);
309 }
310 }
313 void pdf_finalize_name_trees (pdf_file_handle pdf_file)
314 {
315 struct pdf_name_tree *tree;
317 for (tree = pdf_file->name_tree_list; tree; tree = tree->next)
318 pdf_finalize_name_tree_node (tree, tree->root);
319 }