isdb-t/br-sp-FranciscoMorato


1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293

# Channel table for Francisco Morato - SP - Brazil
# Source: http://portalbsd.com.br/novo/terrestres_channels.php?channels=3303

# Physical channel 15
[Mega TV]
	DELIVERY_SYSTEM = ISDBT
	BANDWIDTH_HZ = 6000000
	FREQUENCY = 479142857
	INVERSION = AUTO
	GUARD_INTERVAL = AUTO
	TRANSMISSION_MODE = AUTO
	INVERSION = AUTO
	GUARD_INTERVAL = AUTO
	TRANSMISSION_MODE = AUTO
	ISDBT_LAYER_ENABLED = 7
	ISDBT_SOUND_BROADCASTING = 0
	ISDBT_SB_SUBCHANNEL_ID = 0
	ISDBT_SB_SEGMENT_IDX = 0
	ISDBT_SB_SEGMENT_COUNT = 0
	ISDBT_LAYERA_FEC = AUTO
	ISDBT_LAYERA_MODULATION = QAM/AUTO
	ISDBT_LAYERA_SEGMENT_COUNT = 0
	ISDBT_LAYERA_TIME_INTERLEAVING = 0
	ISDBT_LAYERB_FEC = AUTO
	ISDBT_LAYERB_MODULATION = QAM/AUTO
	ISDBT_LAYERB_SEGMENT_COUNT = 0
	ISDBT_LAYERB_TIME_INTERLEAVING = 0
	ISDBT_LAYERC_FEC = AUTO
	ISDBT_LAYERC_MODULATION = QAM/AUTO
	ISDBT_LAYERC_SEGMENT_COUNT = 0
	ISDBT_LAYERC_TIME_INTERLEAVING = 0

# Physical channel 18
[Globo SP]
	DELIVERY_SYSTEM = ISDBT
	BANDWIDTH_HZ = 6000000
	FREQUENCY = 497142857
	INVERSION = AUTO
	GUARD_INTERVAL = AUTO
	TRANSMISSION_MODE = AUTO
	INVERSION = AUTO
	GUARD_INTERVAL = AUTO
	TRANSMISSION_MODE = AUTO
	ISDBT_LAYER_ENABLED = 7
	ISDBT_SOUND_BROADCASTING = 0
	ISDBT_SB_SUBCHANNEL_ID = 0
	ISDBT_SB_SEGMENT_IDX = 0
	ISDBT_SB_SEGMENT_COUNT = 0
	ISDBT_LAYERA_FEC = AUTO
	ISDBT_LAYERA_MODULATION = QAM/AUTO
	ISDBT_LAYERA_SEGMENT_COUNT = 0
	ISDBT_LAYERA_TIME_INTERLEAVING = 0
	ISDBT_LAYERB_FEC = AUTO
	ISDBT_LAYERB_MODULATION = QAM/AUTO
	ISDBT_LAYERB_SEGMENT_COUNT = 0
	ISDBT_LAYERB_TIME_INTERLEAVING = 0
	ISDBT_LAYERC_FEC = AUTO
	ISDBT_LAYERC_MODULATION = QAM/AUTO
	ISDBT_LAYERC_SEGMENT_COUNT = 0
	ISDBT_LAYERC_TIME_INTERLEAVING = 0

# Physical channel 20
[Rede Record]
	DELIVERY_SYSTEM = ISDBT
	BANDWIDTH_HZ = 6000000
	FREQUENCY = 509142857
	INVERSION = AUTO
	GUARD_INTERVAL = AUTO
	TRANSMISSION_MODE = AUTO
	INVERSION = AUTO
	GUARD_INTERVAL = AUTO
	TRANSMISSION_MODE = AUTO
	ISDBT_LAYER_ENABLED = 7
	ISDBT_SOUND_BROADCASTING = 0
	ISDBT_SB_SUBCHANNEL_ID = 0
	ISDBT_SB_SEGMENT_IDX = 0
	ISDBT_SB_SEGMENT_COUNT = 0
	ISDBT_LAYERA_FEC = AUTO
	ISDBT_LAYERA_MODULATION = QAM/AUTO
	ISDBT_LAYERA_SEGMENT_COUNT = 0
	ISDBT_LAYERA_TIME_INTERLEAVING = 0
	ISDBT_LAYERB_FEC = AUTO
	ISDBT_LAYERB_MODULATION = QAM/AUTO
	ISDBT_LAYERB_SEGMENT_COUNT = 0
	ISDBT_LAYERB_TIME_INTERLEAVING = 0
	ISDBT_LAYERC_FEC = AUTO
	ISDBT_LAYERC_MODULATION = QAM/AUTO
	ISDBT_LAYERC_SEGMENT_COUNT = 0
	ISDBT_LAYERC_TIME_INTERLEAVING = 0

# Physical channel 23
[Band]
	DELIVERY_SYSTEM = ISDBT
	BANDWIDTH_HZ = 6000000
	FREQUENCY = 527142857
	INVERSION = AUTO
	GUARD_INTERVAL = AUTO
	TRANSMISSION_MODE = AUTO
	INVERSION = AUTO
	GUARD_INTERVAL = AUTO
	TRANSMISSION_MODE = AUTO
	ISDBT_LAYER_ENABLED = 7
	ISDBT_SOUND_BROADCASTING = 0
	ISDBT_SB_SUBCHANNEL_ID = 0
	ISDBT_SB_SEGMENT_IDX = 0
	ISDBT_SB_SEGMENT_COUNT = 0
	ISDBT_LAYERA_FEC = AUTO
	ISDBT_LAYERA_MODULATION = QAM/AUTO
	ISDBT_LAYERA_SEGMENT_COUNT = 0
	ISDBT_LAYERA_TIME_INTERLEAVING = 0
	ISDBT_LAYERB_FEC = AUTO
	ISDBT_LAYERB_MODULATION = QAM/AUTO
	ISDBT_LAYERB_SEGMENT_COUNT = 0
	ISDBT_LAYERB_TIME_INTERLEAVING = 0
	ISDBT_LAYERC_FEC = AUTO
	ISDBT_LAYERC_MODULATION = QAM/AUTO
	ISDBT_LAYERC_SEGMENT_COUNT = 0
	ISDBT_LAYERC_TIME_INTERLEAVING = 0

# Physical channel 24
[TV Cultura, Univesp, Multicultura]
	DELIVERY_SYSTEM = ISDBT
	BANDWIDTH_HZ = 6000000
	FREQUENCY = 533142857
	INVERSION = AUTO
	GUARD_INTERVAL = AUTO
	TRANSMISSION_MODE = AUTO
	INVERSION = AUTO
	GUARD_INTERVAL = AUTO
	TRANSMISSION_MODE = AUTO
	ISDBT_LAYER_ENABLED = 7
	ISDBT_SOUND_BROADCASTING = 0
	ISDBT_SB_SUBCHANNEL_ID = 0
	ISDBT_SB_SEGMENT_IDX = 0
	ISDBT_SB_SEGMENT_COUNT = 0
	ISDBT_LAYERA_FEC = AUTO
	ISDBT_LAYERA_MODULATION = QAM/AUTO
	ISDBT_LAYERA_SEGMENT_COUNT = 0
	ISDBT_LAYERA_TIME_INTERLEAVING = 0
	ISDBT_LAYERB_FEC = AUTO
	ISDBT_LAYERB_MODULATION = QAM/AUTO
	ISDBT_LAYERB_SEGMENT_COUNT = 0
	ISDBT_LAYERB_TIME_INTERLEAVING = 0
	ISDBT_LAYERC_FEC = AUTO
	ISDBT_LAYERC_MODULATION = QAM/AUTO
	ISDBT_LAYERC_SEGMENT_COUNT = 0
	ISDBT_LAYERC_TIME_INTERLEAVING = 0

# Physical channel 28
[SBT SP]
	DELIVERY_SYSTEM = ISDBT
	BANDWIDTH_HZ = 6000000
	FREQUENCY = 557142857
	INVERSION = AUTO
	GUARD_INTERVAL = AUTO
	TRANSMISSION_MODE = AUTO
	INVERSION = AUTO
	GUARD_INTERVAL = AUTO
	TRANSMISSION_MODE = AUTO
	ISDBT_LAYER_ENABLED = 7
	ISDBT_SOUND_BROADCASTING = 0
	ISDBT_SB_SUBCHANNEL_ID = 0
	ISDBT_SB_SEGMENT_IDX = 0
	ISDBT_SB_SEGMENT_COUNT = 0
	ISDBT_LAYERA_FEC = AUTO
	ISDBT_LAYERA_MODULATION = QAM/AUTO
	ISDBT_LAYERA_SEGMENT_COUNT = 0
	ISDBT_LAYERA_TIME_INTERLEAVING = 0
	ISDBT_LAYERB_FEC = AUTO
	ISDBT_LAYERB_MODULATION = QAM/AUTO
	ISDBT_LAYERB_SEGMENT_COUNT = 0
	ISDBT_LAYERB_TIME_INTERLEAVING = 0
	ISDBT_LAYERC_FEC = AUTO
	ISDBT_LAYERC_MODULATION = QAM/AUTO
	ISDBT_LAYERC_SEGMENT_COUNT = 0
	ISDBT_LAYERC_TIME_INTERLEAVING = 0

# Physical channel 29
[Rede TV!]
	DELIVERY_SYSTEM = ISDBT
	BANDWIDTH_HZ = 6000000
	FREQUENCY = 563142857
	INVERSION = AUTO
	GUARD_INTERVAL = AUTO
	TRANSMISSION_MODE = AUTO
	INVERSION = AUTO
	GUARD_INTERVAL = AUTO
	TRANSMISSION_MODE = AUTO
	ISDBT_LAYER_ENABLED = 7
	ISDBT_SOUND_BROADCASTING = 0
	ISDBT_SB_SUBCHANNEL_ID = 0
	ISDBT_SB_SEGMENT_IDX = 0
	ISDBT_SB_SEGMENT_COUNT = 0
	ISDBT_LAYERA_FEC = AUTO
	ISDBT_LAYERA_MODULATION = QAM/AUTO
	ISDBT_LAYERA_SEGMENT_COUNT = 0
	ISDBT_LAYERA_TIME_INTERLEAVING = 0
	ISDBT_LAYERB_FEC = AUTO
	ISDBT_LAYERB_MODULATION = QAM/AUTO
	ISDBT_LAYERB_SEGMENT_COUNT = 0
	ISDBT_LAYERB_TIME_INTERLEAVING = 0
	ISDBT_LAYERC_FEC = AUTO
	ISDBT_LAYERC_MODULATION = QAM/AUTO
	ISDBT_LAYERC_SEGMENT_COUNT = 0
	ISDBT_LAYERC_TIME_INTERLEAVING = 0

# Physical channel 31
[Ideal TV]
	DELIVERY_SYSTEM = ISDBT
	BANDWIDTH_HZ = 6000000
	FREQUENCY = 575142857
	INVERSION = AUTO
	GUARD_INTERVAL = AUTO
	TRANSMISSION_MODE = AUTO
	INVERSION = AUTO
	GUARD_INTERVAL = AUTO
	TRANSMISSION_MODE = AUTO
	ISDBT_LAYER_ENABLED = 7
	ISDBT_SOUND_BROADCASTING = 0
	ISDBT_SB_SUBCHANNEL_ID = 0
	ISDBT_SB_SEGMENT_IDX = 0
	ISDBT_SB_SEGMENT_COUNT = 0
	ISDBT_LAYERA_FEC = AUTO
	ISDBT_LAYERA_MODULATION = QAM/AUTO
	ISDBT_LAYERA_SEGMENT_COUNT = 0
	ISDBT_LAYERA_TIME_INTERLEAVING = 0
	ISDBT_LAYERB_FEC = AUTO
	ISDBT_LAYERB_MODULATION = QAM/AUTO
	ISDBT_LAYERB_SEGMENT_COUNT = 0
	ISDBT_LAYERB_TIME_INTERLEAVING = 0
	ISDBT_LAYERC_FEC = AUTO
	ISDBT_LAYERC_MODULATION = QAM/AUTO
	ISDBT_LAYERC_SEGMENT_COUNT = 0
	ISDBT_LAYERC_TIME_INTERLEAVING = 0

# Physical channel 35
[Top TV]
	DELIVERY_SYSTEM = ISDBT
	BANDWIDTH_HZ = 6000000
	FREQUENCY = 599142857
	INVERSION = AUTO
	GUARD_INTERVAL = AUTO
	TRANSMISSION_MODE = AUTO
	INVERSION = AUTO
	GUARD_INTERVAL = AUTO
	TRANSMISSION_MODE = AUTO
	ISDBT_LAYER_ENABLED = 7
	ISDBT_SOUND_BROADCASTING = 0
	ISDBT_SB_SUBCHANNEL_ID = 0
	ISDBT_SB_SEGMENT_IDX = 0
	ISDBT_SB_SEGMENT_COUNT = 0
	ISDBT_LAYERA_FEC = AUTO
	ISDBT_LAYERA_MODULATION = QAM/AUTO
	ISDBT_LAYERA_SEGMENT_COUNT = 0
	ISDBT_LAYERA_TIME_INTERLEAVING = 0
	ISDBT_LAYERB_FEC = AUTO
	ISDBT_LAYERB_MODULATION = QAM/AUTO
	ISDBT_LAYERB_SEGMENT_COUNT = 0
	ISDBT_LAYERB_TIME_INTERLEAVING = 0
	ISDBT_LAYERC_FEC = AUTO
	ISDBT_LAYERC_MODULATION = QAM/AUTO
	ISDBT_LAYERC_SEGMENT_COUNT = 0
	ISDBT_LAYERC_TIME_INTERLEAVING = 0

# Physical channel 47
[NGT]
	DELIVERY_SYSTEM = ISDBT
	BANDWIDTH_HZ = 6000000
	FREQUENCY = 671142857
	INVERSION = AUTO
	GUARD_INTERVAL = AUTO
	TRANSMISSION_MODE = AUTO
	INVERSION = AUTO
	GUARD_INTERVAL = AUTO
	TRANSMISSION_MODE = AUTO
	ISDBT_LAYER_ENABLED = 7
	ISDBT_SOUND_BROADCASTING = 0
	ISDBT_SB_SUBCHANNEL_ID = 0
	ISDBT_SB_SEGMENT_IDX = 0
	ISDBT_SB_SEGMENT_COUNT = 0
	ISDBT_LAYERA_FEC = AUTO
	ISDBT_LAYERA_MODULATION = QAM/AUTO
	ISDBT_LAYERA_SEGMENT_COUNT = 0
	ISDBT_LAYERA_TIME_INTERLEAVING = 0
	ISDBT_LAYERB_FEC = AUTO
	ISDBT_LAYERB_MODULATION = QAM/AUTO
	ISDBT_LAYERB_SEGMENT_COUNT = 0
	ISDBT_LAYERB_TIME_INTERLEAVING = 0
	ISDBT_LAYERC_FEC = AUTO
	ISDBT_LAYERC_MODULATION = QAM/AUTO
	ISDBT_LAYERC_SEGMENT_COUNT = 0
	ISDBT_LAYERC_TIME_INTERLEAVING = 0
/* $Id: evaluator.c,v 1.25 2005/05/08 04:32:44 reinelt Exp $
 *
 * expression evaluation
 *
 * Copyright (C) 1999, 2000 Michael Reinelt <reinelt@eunet.at>
 * Copyright (C) 2004 The LCD4Linux Team <lcd4linux-devel@users.sourceforge.net>
 *
 * This file is part of LCD4Linux.
 *
 * LCD4Linux is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2, or (at your option)
 * any later version.
 *
 * LCD4Linux is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 *
 * $Log: evaluator.c,v $
 * Revision 1.25  2005/05/08 04:32:44  reinelt
 * CodingStyle added and applied
 *
 * Revision 1.24  2005/03/30 04:57:50  reinelt
 * Evaluator speedup: use bsearch for finding functions and variables
 *
 * Revision 1.23  2005/01/18 06:30:23  reinelt
 * added (C) to all copyright statements
 *
 * Revision 1.22  2004/06/26 12:04:59  reinelt
 *
 * uh-oh... the last CVS log message messed up things a lot...
 *
 * Revision 1.21  2004/06/26 09:27:21  reinelt
 *
 * added '-W' to CFLAGS
 * changed all C++ comments to C ones
 * cleaned up a lot of signed/unsigned mistakes
 *
 * Revision 1.20  2004/06/20 10:09:56  reinelt
 *
 * 'const'ified the whole source
 *
 * Revision 1.19  2004/04/12 11:12:25  reinelt
 * added plugin_isdn, removed old ISDN client
 * fixed some real bad bugs in the evaluator
 *
 * Revision 1.18  2004/03/11 06:39:58  reinelt
 * big patch from Martin:
 * - reuse filehandles
 * - memory leaks fixed
 * - earlier busy-flag checking with HD44780
 * - reuse memory for strings in RESULT and hash
 * - netdev_fast to wavid time-consuming regex
 *
 * Revision 1.17  2004/03/08 18:45:52  hejl
 * fixed segfault when using string concatenation
 *
 * Revision 1.16  2004/03/08 04:33:08  reinelt
 * string concatenation fixed
 *
 * Revision 1.15  2004/03/06 20:31:16  reinelt
 * Complete rewrite of the evaluator to get rid of the code
 * from mark Morley (because of license issues).
 * The new Evaluator does a pre-compile of expressions, and
 * stores them in trees. Therefore it should be reasonable faster...
 *
 * Revision 1.14  2004/03/03 03:47:04  reinelt
 * big patch from Martin Hejl:
 * - use qprintf() where appropriate
 * - save CPU cycles on gettimeofday()
 * - add quit() functions to free allocated memory
 * - fixed lots of memory leaks
 *
 * Revision 1.13  2004/02/26 21:42:45  reinelt
 * memory leak fixes from Martin
 *
 * Revision 1.12  2004/02/05 07:10:23  reinelt
 * evaluator function names are no longer case-sensitive
 * Crystalfontz Fan PWM control, Fan RPM monitoring, temperature monitoring
 *
 * Revision 1.11  2004/01/30 20:57:56  reinelt
 * HD44780 patch from Martin Hejl
 * dmalloc integrated
 *
 * Revision 1.10  2004/01/29 04:40:02  reinelt
 * every .c file includes "config.h" now
 *
 * Revision 1.9  2004/01/15 07:47:02  reinelt
 * debian/ postinst and watch added (did CVS forget about them?)
 * evaluator: conditional expressions (a?b:c) added
 * text widget nearly finished
 *
 * Revision 1.8  2004/01/12 03:51:01  reinelt
 * evaluating the 'Variables' section in the config file
 *
 * Revision 1.7  2004/01/07 10:15:41  reinelt
 * small glitch in evaluator fixed
 * made config table sorted and access with bsearch(),
 * which should be much faster
 *
 * Revision 1.6  2004/01/06 23:01:37  reinelt
 * more copyright issues
 *
 * Revision 1.5  2004/01/06 17:33:45  reinelt
 * Evaluator: functions with variable argument lists
 * Evaluator: plugin_sample.c and README.Plugins added
 *
 * Revision 1.4  2004/01/06 15:19:12  reinelt
 * Evaluator rearrangements...
 *
 * Revision 1.3  2003/10/11 06:01:52  reinelt
 * renamed expression.{c,h} to client.{c,h}
 * added config file client
 * new functions 'AddNumericVariable()' and 'AddStringVariable()'
 * new parameter '-i' for interactive mode
 *
 * Revision 1.2  2003/10/06 05:47:27  reinelt
 * operators: ==, \!=, <=, >=
 *
 * Revision 1.1  2003/10/06 04:34:06  reinelt
 * expression evaluator added
 *
 */


/* 
 * exported functions:
 *
 * int SetVariable (char *name, RESULT *value)
 *   adds a generic variable to the evaluator
 *
 * int SetVariableNumeric (char *name, double value)
 *   adds a numerical variable to the evaluator
 *
 * int SetVariableString (char *name, char *value)
 *   adds a numerical variable to the evaluator
 *
 * int AddFunction (char *name, int argc, void (*func)())
 *   adds a function to the evaluator
 *
 * void DeleteVariables    (void);
 *   frees all allocated variables
 *
 * void DeleteFunctions    (void);
 *   frees all allocated functions
 *
 * void DelResult (RESULT *result)
 *   sets a result to none
 *   frees a probably allocated memory
 *
 * RESULT* SetResult (RESULT **result, int type, void *value)
 *   initializes a result
 *
 * double R2N (RESULT *result)
 *   converts a result into a number
 *
 * char* R2S (RESULT *result)
 *   converts a result into a string
 *
 *
 * int Compile (char* expression, void **tree)
 *   compiles a expression into a tree
 * 
 * int Eval (void *tree, RESULT *result)
 *   evaluates an expression
 *
 * void DelTree (void *tree)
 *   frees a compiled tree
 */


#include "config.h"

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include <math.h>
#include <setjmp.h>

#include "debug.h"
#include "evaluator.h"

#ifdef WITH_DMALLOC
#include <dmalloc.h>
#endif

/* string buffer chunk size */
#define CHUNK_SIZE 16

typedef enum {
    T_UNDEF,
    T_NAME,
    T_NUMBER,
    T_STRING,
    T_OPERATOR,
    T_VARIABLE,
    T_FUNCTION
} TOKEN;

typedef enum {
    O_UNDEF,			/* undefined */
    O_LST,			/* expression lists */
    O_SET,			/* variable assignements */
    O_CND,			/* conditional a?b:c */
    O_COL,			/* colon in a?b:c */
    O_OR,			/* logical OR */
    O_AND,			/* logical AND */
    O_EQ,			/* equal */
    O_NE,			/* not equal */
    O_LT,			/* less than */
    O_LE,			/* less or equal */
    O_GT,			/* greater than */
    O_GE,			/* greater or equal */
    O_ADD,			/* addition */
    O_SUB,			/* subtraction */
    O_SGN,			/* sign '-' */
    O_CAT,			/* string concatenation */
    O_MUL,			/* multiplication */
    O_DIV,			/* division */
    O_MOD,			/* modulo */
    O_POW,			/* power */
    O_NOT,			/* logical NOT */
    O_BRO,			/* open brace */
    O_COM,			/* comma (argument seperator) */
    O_BRC			/* closing brace */
} OPERATOR;

typedef struct {
    char *pattern;
    int len;
    OPERATOR op;
} PATTERN;

typedef struct {
    char *name;
    RESULT *value;
} VARIABLE;

typedef struct {
    char *name;
    int argc;
    void (*func) ();
} FUNCTION;

typedef struct _NODE {
    TOKEN Token;
    OPERATOR Operator;
    RESULT *Result;
    VARIABLE *Variable;
    FUNCTION *Function;
    int Children;
    struct _NODE **Child;
} NODE;


/* operators */
/* IMPORTANT! list must be sorted by length! */
static PATTERN Pattern[] = {
    {";", 1, O_LST},		/* expression lists */
    {"=", 1, O_SET},		/* variable assignements */
    {"?", 1, O_CND},		/* conditional a?b:c */
    {":", 1, O_COL},		/* colon a?b:c */
    {"|", 1, O_OR},		/* logical OR */
    {"&", 1, O_AND},		/* logical AND */
    {"<", 1, O_LT},		/* less than */
    {">", 1, O_GT},		/* greater than */
    {"+", 1, O_ADD},		/* addition */
    {"-", 1, O_SUB},		/* subtraction or sign */
    {".", 1, O_CAT},		/* string concatenation */
    {"*", 1, O_MUL},		/* multiplication */
    {"/", 1, O_DIV},		/* division */
    {"%", 1, O_MOD},		/* modulo */
    {"^", 1, O_POW},		/* power */
    {"!", 1, O_NOT},		/* logical NOT */
    {"(", 1, O_BRO},		/* open brace */
    {",", 1, O_COM},		/* comma (argument seperator) */
    {")", 1, O_BRC},		/* closing brace */
    {"==", 2, O_EQ},		/* equal */
    {"!=", 2, O_NE},		/* not equal */
    {"<=", 2, O_LE},		/* less or equal */
    {">=", 2, O_GE}		/* greater or equal */
};


static char *Expression = NULL;
static char *ExprPtr = NULL;
static char *Word = NULL;
static TOKEN Token = T_UNDEF;
static OPERATOR Operator = O_UNDEF;

static VARIABLE *Variable = NULL;
static int nVariable = 0;

static FUNCTION *Function = NULL;
static int nFunction = 0;


void DelResult(RESULT * result)
{
    result->type = 0;
    result->number = 0.0;
    result->length = -1;
    if (result->string) {
	free(result->string);
	result->string = NULL;
    }
}


static void FreeResult(RESULT * result)
{
    if (result != NULL) {
	DelResult(result);
	free(result);
    }
}


static RESULT *NewResult(void)
{
    RESULT *result = malloc(sizeof(RESULT));
    if (result == NULL) {
	error("Evaluator: cannot allocate result: out of memory!");
	return NULL;
    }
    result->type = 0;
    result->number = 0.0;
    result->length = -1;
    result->string = NULL;

    return result;
}


static RESULT *DupResult(RESULT * result)
{
    RESULT *result2;

    if ((result2 = NewResult()) == NULL)
	return NULL;

    result2->type = result->type;
    result2->number = result->number;

    if (result->length >= 0) {
	result2->length = result->length;
	result2->string = malloc(result2->length);
	strcpy(result2->string, result->string);
    } else {
	result2->length = -1;
	result2->string = NULL;
    }

    return result2;
}


RESULT *SetResult(RESULT ** result, const int type, const void *value)
{
    if (*result == NULL) {
	if ((*result = NewResult()) == NULL)
	    return NULL;
    } else if (type == R_NUMBER) {
	DelResult(*result);
    }

    if (type == R_NUMBER) {
	(*result)->type = R_NUMBER;
	(*result)->number = *(double *) value;
	(*result)->length = -1;
	(*result)->string = NULL;
    }

    else if (type == R_STRING) {
	int len = strlen((char *) value);
	(*result)->type = R_STRING;
	(*result)->number = 0.0;
	if ((*result)->string == NULL || len > (*result)->length) {
	    /* buffer is either empty or too small */
	    if ((*result)->string)
		free((*result)->string);
	    /* allocate memory in multiples of CHUNK_SIZE */
	    /* note that length does not count the trailing \0 */
	    (*result)->length = CHUNK_SIZE * (len / CHUNK_SIZE + 1) - 1;
	    (*result)->string = malloc((*result)->length + 1);
	}
	strcpy((*result)->string, value);
    } else {
	error("Evaluator: internal error: invalid result type %d", type);
	return NULL;
    }

    return *result;
}


double R2N(RESULT * result)
{
    if (result == NULL) {
	error("Evaluator: internal error: NULL result");
	return 0.0;
    }

    if (result->type & R_NUMBER) {
	return result->number;
    }

    if (result->type & R_STRING) {
	result->type |= R_NUMBER;
	result->number = atof(result->string);
	return result->number;
    }

    error("Evaluator: internal error: invalid result type %d", result->type);
    return 0.0;
}


char *R2S(RESULT * result)
{
    if (result == NULL) {
	error("Evaluator: internal error: NULL result");
	return NULL;
    }

    if (result->type & R_STRING) {
	return result->string;
    }

    if (result->type & R_NUMBER) {
	result->type |= R_STRING;
	if (result->string)
	    free(result->string);
	result->length = CHUNK_SIZE - 1;
	result->string = malloc(CHUNK_SIZE);
	snprintf(result->string, CHUNK_SIZE, "%g", result->number);
	return result->string;
    }

    error("Evaluator: internal error: invalid result type %d", result->type);
    return NULL;

}


/* bsearch compare function for variables */
static int LookupVariable(const void *a, const void *b)
{
    char *key = (char *) a;
    VARIABLE *var = (VARIABLE *) b;

    return strcmp(key, var->name);
}


/* qsort compare function for variables */
static int SortVariable(const void *a, const void *b)
{
    VARIABLE *va = (VARIABLE *) a;
    VARIABLE *vb = (VARIABLE *) b;

    return strcmp(va->name, vb->name);
}


static VARIABLE *FindVariable(const char *name)
{
    return bsearch(name, Variable, nVariable, sizeof(VARIABLE), LookupVariable);
}


int SetVariable(const char *name, RESULT * value)
{
    VARIABLE *V;

    V = FindVariable(name);
    if (V != NULL) {
	FreeResult(V->value);
	V->value = DupResult(value);
	return 1;
    }

    nVariable++;
    Variable = realloc(Variable, nVariable * sizeof(VARIABLE));
    Variable[nVariable - 1].name = strdup(name);
    Variable[nVariable - 1].value = DupResult(value);

    qsort(Variable, nVariable, sizeof(VARIABLE), SortVariable);

    return 0;
}


int SetVariableNumeric(const char *name, const double value)
{
    RESULT result = { 0, 0, 0, NULL };
    RESULT *rp = &result;

    SetResult(&rp, R_NUMBER, &value);

    return SetVariable(name, rp);
}


int SetVariableString(const char *name, const char *value)
{
    RESULT result = { 0, 0, 0, NULL };
    RESULT *rp = &result;

    SetResult(&rp, R_STRING, value);

    return SetVariable(name, rp);
}


void DeleteVariables(void)
{
    int i;

    for (i = 0; i < nVariable; i++) {
	free(Variable[i].name);
	FreeResult(Variable[i].value);
    }
    free(Variable);
    Variable = NULL;
    nVariable = 0;
}


/* bsearch compare function for functions */
static int LookupFunction(const void *a, const void *b)
{
    char *n = (char *) a;
    FUNCTION *f = (FUNCTION *) b;

    return strcmp(n, f->name);
}


/* qsort compare function for functions */
static int SortFunction(const void *a, const void *b)
{
    FUNCTION *fa = (FUNCTION *) a;
    FUNCTION *fb = (FUNCTION *) b;

    return strcmp(fa->name, fb->name);
}


static FUNCTION *FindFunction(const char *name)
{
    return bsearch(name, Function, nFunction, sizeof(FUNCTION), LookupFunction);
}


int AddFunction(const char *name, const int argc, void (*func) ())
{
    nFunction++;
    Function = realloc(Function, nFunction * sizeof(FUNCTION));
    Function[nFunction - 1].name = strdup(name);
    Function[nFunction - 1].argc = argc;
    Function[nFunction - 1].func = func;

    qsort(Function, nFunction, sizeof(FUNCTION), SortFunction);

    return 0;
}


void DeleteFunctions(void)
{
    int i;

    for (i = 0; i < nFunction; i++) {
	free(Function[i].name);
    }
    free(Function);
    Function = NULL;
    nFunction = 0;
}


#define is_space(c)  ((c) == ' ' || (c) == '\t')
#define is_digit(c)  ((c) >= '0' && (c) <= '9')
#define is_alpha(c) (((c) >= 'A' && (c) <= 'Z') || ((c) >= 'a' && (c) <= 'z') || ((c) == '_'))
#define is_alnum(c) (is_alpha(c) || is_digit(c))

static void Parse(void)
{
    Token = T_UNDEF;
    Operator = O_UNDEF;

    if (Word) {
	free(Word);
	Word = NULL;
    }

    /* NULL expression? */
    if (ExprPtr == NULL) {
	Word = strdup("");
	return;
    }

    /* skip leading whitespace */
    while (is_space(*ExprPtr))
	ExprPtr++;

    /* names */
    if (is_alpha(*ExprPtr)) {
	char *start = ExprPtr;
	while (is_alnum(*ExprPtr))
	    ExprPtr++;
	if (*ExprPtr == ':' && *(ExprPtr + 1) == ':' && is_alpha(*(ExprPtr + 2))) {
	    ExprPtr += 3;
	    while (is_alnum(*ExprPtr))
		ExprPtr++;
	}
	Word = strndup(start, ExprPtr - start);
	Token = T_NAME;
    }

    /* numbers */
    else if (is_digit(*ExprPtr) || (*ExprPtr == '.' && is_digit(*(ExprPtr + 1)))) {
	char *start = ExprPtr;
	while (is_digit(*ExprPtr))
	    ExprPtr++;
	if (*ExprPtr == '.') {
	    ExprPtr++;
	    while (is_digit(*ExprPtr))
		ExprPtr++;
	}
	Word = strndup(start, ExprPtr - start);
	Token = T_NUMBER;
    }

    /* strings */
    else if (*ExprPtr == '\'') {
	char *start = ++ExprPtr;
	while (*ExprPtr != '\0' && *ExprPtr != '\'')
	    ExprPtr++;
	Word = strndup(start, ExprPtr - start);
	Token = T_STRING;
	if (*ExprPtr == '\'')
	    ExprPtr++;
    }

    /* operators */
    else {
	int i;
	for (i = sizeof(Pattern) / sizeof(Pattern[0]) - 1; i >= 0; i--) {
	    int len = Pattern[i].len;
	    if (strncmp(ExprPtr, Pattern[i].pattern, Pattern[i].len) == 0) {
		Word = strndup(ExprPtr, len);
		Token = T_OPERATOR;
		Operator = Pattern[i].op;
		ExprPtr += len;
		break;
	    }
	}
    }

    /* syntax check */
    if (Token == T_UNDEF && *ExprPtr != '\0') {
	error("Evaluator: parse error in <%s>: garbage <%s>", Expression, ExprPtr);
    }

    /* skip trailing whitespace */
    while (is_space(*ExprPtr))
	ExprPtr++;

    /* empty token */
    if (Word == NULL)
	Word = strdup("");
}


static NODE *NewNode(NODE * Child)
{
    NODE *N;

    N = malloc(sizeof(NODE));
    if (N == NULL)
	return NULL;

    memset(N, 0, sizeof(NODE));
    N->Token = Token;
    N->Operator = Operator;

    if (Child != NULL) {
	N->Children = 1;
	N->Child = malloc(sizeof(NODE *));
	N->Child[0] = Child;
    }

    return N;

}


static NODE *JunkNode(void)
{
    NODE *Junk;

    Junk = NewNode(NULL);
    Junk->Token = T_STRING;
    SetResult(&Junk->Result, R_STRING, "");

    return Junk;
}


static void LinkNode(NODE * Root, NODE * Child)
{

    if (Child == NULL)
	return;

    Root->Children++;
    Root->Child = realloc(Root->Child, Root->Children * sizeof(NODE *));
    if (Root->Child == NULL)
	return;
    Root->Child[Root->Children - 1] = Child;
}


/* forward declaration */
static NODE *Level01(void);


/* literal numbers, variables, functions */
static NODE *Level12(void)
{
    NODE *Root = NULL;

    if (Token == T_OPERATOR && Operator == O_BRO) {
	Parse();
	Root = Level01();
	if (Token != T_OPERATOR || Operator != O_BRC) {
	    error("Evaluator: unbalanced parentheses in <%s>", Expression);
	    LinkNode(Root, JunkNode());
	}
    }

    else if (Token == T_NUMBER) {
	double value = atof(Word);
	Root = NewNode(NULL);
	SetResult(&Root->Result, R_NUMBER, &value);
    }

    else if (Token == T_STRING) {
	Root = NewNode(NULL);
	SetResult(&Root->Result, R_STRING, Word);
    }

    else if (Token == T_NAME) {

	/* look-ahead for opening brace */
	if (*ExprPtr == '(') {
	    int argc = 0;
	    Root = NewNode(NULL);
	    Root->Token = T_FUNCTION;
	    Root->Result = NewResult();
	    Root->Function = FindFunction(Word);
	    if (Root->Function == NULL) {
		error("Evaluator: unknown function '%s' in <%s>", Word, Expression);
		Root->Token = T_STRING;
		SetResult(&Root->Result, R_STRING, "");
	    }

	    /* opening brace */
	    Parse();
	    do {
		Parse();	/* read argument */
		if (Token == T_OPERATOR && Operator == O_BRC) {
		    break;
		} else if (Token == T_OPERATOR && Operator == O_COM) {
		    error("Evaluator: empty argument in <%s>", Expression);
		    LinkNode(Root, JunkNode());
		} else {
		    LinkNode(Root, Level01());
		}
		argc++;
	    } while (Token == T_OPERATOR && Operator == O_COM);

	    /* check for closing brace */
	    if (Token != T_OPERATOR || Operator != O_BRC) {
		error("Evaluator: missing closing brace in <%s>", Expression);
	    }

	    /* check number of arguments */
	    if (Root->Function != NULL && Root->Function->argc >= 0 && Root->Function->argc != argc) {
		error("Evaluator: wrong number of arguments in <%s>", Expression);
		while (argc < Root->Function->argc) {
		    LinkNode(Root, JunkNode());
		    argc++;
		}
	    }

	} else {
	    Root = NewNode(NULL);
	    Root->Token = T_VARIABLE;
	    Root->Result = NewResult();
	    Root->Variable = FindVariable(Word);
	    if (Root->Variable == NULL) {
		SetVariableString(Word, "");
		Root->Variable = FindVariable(Word);
	    }
	}
    }

    else {
	error("Evaluator: syntax error in <%s>: <%s>", Expression, Word);
	Root = NewNode(NULL);
	Root->Token = T_STRING;
	SetResult(&Root->Result, R_STRING, "");
    }

    Parse();
    return Root;

}


/* unary + or - signs or logical 'not' */
static NODE *Level11(void)
{
    NODE *Root;
    TOKEN sign = T_UNDEF;

    if (Token == T_OPERATOR && (Operator == O_ADD || Operator == O_SUB || Operator == O_NOT)) {
	sign = Operator;
	if (sign == O_SUB)
	    sign = O_SGN;
	Parse();
    }

    Root = Level12();

    if (sign == O_SGN || sign == O_NOT) {
	Root = NewNode(Root);
	Root->Token = T_OPERATOR;
	Root->Operator = sign;
    }

    return Root;
}


/* x^y */
static NODE *Level10(void)
{
    NODE *Root;

    Root = Level11();

    while (Token == T_OPERATOR && Operator == O_POW) {
	Root = NewNode(Root);
	Parse();
	LinkNode(Root, Level11());
    }

    return Root;
}


/* multiplication, division, modulo */
static NODE *Level09(void)
{
    NODE *Root;

    Root = Level10();

    while (Token == T_OPERATOR && (Operator == O_MUL || Operator == O_DIV || Operator == O_MOD)) {
	Root = NewNode(Root);
	Parse();
	LinkNode(Root, Level10());
    }

    return Root;
}


/* addition, subtraction, string concatenation */
static NODE *Level08(void)
{
    NODE *Root;

    Root = Level09();

    while (Token == T_OPERATOR && (Operator == O_ADD || Operator == O_SUB || Operator == O_CAT)) {
	Root = NewNode(Root);
	Parse();
	LinkNode(Root, Level09());
    }

    return Root;
}


/* relational operators */
static NODE *Level07(void)
{
    NODE *Root;

    Root = Level08();

    while (Token == T_OPERATOR && (Operator == O_GT || Operator == O_GE || Operator == O_LT || Operator == O_LE)) {
	Root = NewNode(Root);
	Parse();
	LinkNode(Root, Level08());
    }

    return Root;
}


/* equal, not equal */
static NODE *Level06(void)
{
    NODE *Root;

    Root = Level07();

    while (Token == T_OPERATOR && (Operator == O_EQ || Operator == O_NE)) {
	Root = NewNode(Root);
	Parse();
	LinkNode(Root, Level07());
    }

    return Root;
}

/* logical 'and' */
static NODE *Level05(void)
{
    NODE *Root;

    Root = Level06();

    while (Token == T_OPERATOR && Operator == O_AND) {
	Root = NewNode(Root);
	Parse();
	LinkNode(Root, Level06());
    }

    return Root;
}


/* logical 'or' */
static NODE *Level04(void)
{
    NODE *Root;

    Root = Level05();

    while (Token == T_OPERATOR && Operator == O_OR) {
	Root = NewNode(Root);
	Parse();
	LinkNode(Root, Level05());
    }

    return Root;
}


/* conditional expression a?b:c */
static NODE *Level03(void)
{
    NODE *Root;

    Root = Level04();

    if (Token == T_OPERATOR && Operator == O_CND) {
	Root = NewNode(Root);
	Parse();
	LinkNode(Root, Level04());
	if (Token == T_OPERATOR && Operator == O_COL) {
	    Parse();
	    LinkNode(Root, Level04());
	} else {
	    error("Evaluator: syntax error in <%s>: expecting ':' got '%s'", Expression, Word);
	    LinkNode(Root, JunkNode());
	}
    }

    return Root;
}


/* variable assignments */
static NODE *Level02(void)
{
    NODE *Root;

    /* we have to do a look-ahead if it's really an assignment */
    if ((Token == T_NAME) && (*ExprPtr == '=') && (*(ExprPtr + 1) != '=')) {
	char *name = strdup(Word);
	VARIABLE *V = FindVariable(name);
	if (V == NULL) {
	    SetVariableString(name, "");
	    V = FindVariable(name);
	}
	Parse();
	Root = NewNode(NULL);
	Root->Variable = V;
	Parse();
	LinkNode(Root, Level03());
	free(name);
    } else {
	Root = Level03();
    }

    return Root;
}


/* expression lists */
static NODE *Level01(void)
{
    NODE *Root;

    Root = Level02();

    while (Token == T_OPERATOR && Operator == O_LST) {
	Root = NewNode(Root);
	Parse();
	LinkNode(Root, Level02());
    }

    return Root;
}


static int EvalTree(NODE * Root)
{
    int i;
    int argc;
    int type = -1;
    double number = 0.0;
    double dummy;
    int freeme = 0;
    char *string = NULL;
    char *s1, *s2;
    RESULT *param[10];

    for (i = 0; i < Root->Children; i++) {
	EvalTree(Root->Child[i]);
    }

    switch (Root->Token) {

    case T_NUMBER:
    case T_STRING:
	/* Root->Result already contains the value */
	return 0;

    case T_VARIABLE:
	DelResult(Root->Result);
	Root->Result = DupResult(Root->Variable->value);
	return 0;

    case T_FUNCTION:
	DelResult(Root->Result);
	/* prepare parameter list */
	argc = Root->Children;
	if (argc > 10)
	    argc = 10;
	for (i = 0; i < argc; i++) {
	    param[i] = Root->Child[i]->Result;
	}
	if (Root->Function->argc < 0) {
	    /* Function with variable argument list:  */
	    /* pass number of arguments as first parameter */
	    Root->Function->func(Root->Result, argc, &param);
	} else {
	    Root->Function->func(Root->Result, param[0], param[1], param[2], param[3], param[4], param[5], param[6], param[7], param[8], param[9]);
	}
	return 0;

    case T_OPERATOR:
	switch (Root->Operator) {

	case O_LST:		/* expression list: result is last expression */
	    i = Root->Children - 1;
	    type = Root->Child[i]->Result->type;
	    number = Root->Child[i]->Result->number;
	    string = Root->Child[i]->Result->string;
	    break;

	case O_SET:		/* variable assignment */
	    DelResult(Root->Variable->value);
	    Root->Variable->value = DupResult(Root->Child[0]->Result);
	    type = Root->Child[0]->Result->type;
	    number = Root->Child[0]->Result->number;
	    string = Root->Child[0]->Result->string;
	    break;

	case O_CND:		/* conditional expression */
	    i = 1 + (R2N(Root->Child[0]->Result) == 0.0);
	    type = Root->Child[i]->Result->type;
	    number = Root->Child[i]->Result->number;
	    string = Root->Child[i]->Result->string;
	    break;

	case O_OR:		/* logical OR */
	    type = R_NUMBER;
	    number = ((R2N(Root->Child[0]->Result) != 0.0) || (R2N(Root->Child[1]->Result) != 0.0));
	    break;

	case O_AND:		/* logical AND */
	    type = R_NUMBER;
	    number = ((R2N(Root->Child[0]->Result) != 0.0) && (R2N(Root->Child[1]->Result) != 0.0));
	    break;

	case O_EQ:		/* numeric equal */
	    type = R_NUMBER;
	    number = (R2N(Root->Child[0]->Result) == R2N(Root->Child[1]->Result));
	    break;

	case O_NE:		/* numeric not equal */
	    type = R_NUMBER;
	    number = (R2N(Root->Child[0]->Result) != R2N(Root->Child[1]->Result));
	    break;

	case O_LT:		/* numeric less than */
	    type = R_NUMBER;
	    number = (R2N(Root->Child[0]->Result) < R2N(Root->Child[1]->Result));
	    break;

	case O_LE:		/* numeric less equal */
	    type = R_NUMBER;
	    number = (R2N(Root->Child[0]->Result) <= R2N(Root->Child[1]->Result));
	    break;

	case O_GT:		/* numeric greater than */
	    type = R_NUMBER;
	    number = (R2N(Root->Child[0]->Result) > R2N(Root->Child[1]->Result));
	    break;

	case O_GE:		/* numeric greater equal */
	    type = R_NUMBER;
	    number = (R2N(Root->Child[0]->Result) >= R2N(Root->Child[1]->Result));
	    break;

	case O_ADD:		/* addition */
	    type = R_NUMBER;
	    number = R2N(Root->Child[0]->Result) + R2N(Root->Child[1]->Result);
	    break;

	case O_SUB:		/* subtraction */
	    type = R_NUMBER;
	    number = R2N(Root->Child[0]->Result) - R2N(Root->Child[1]->Result);
	    break;

	case O_SGN:		/* sign */
	    type = R_NUMBER;
	    number = -R2N(Root->Child[0]->Result);
	    break;

	case O_CAT:		/* string concatenation */
	    type = R_STRING;
	    s1 = R2S(Root->Child[0]->Result);
	    s2 = R2S(Root->Child[1]->Result);
	    string = malloc(strlen(s1) + strlen(s2) + 1);
	    strcpy(string, s1);
	    strcat(string, s2);
	    freeme = 1;
	    break;

	case O_MUL:		/* multiplication */
	    type = R_NUMBER;
	    number = R2N(Root->Child[0]->Result) * R2N(Root->Child[1]->Result);
	    break;

	case O_DIV:		/* division */
	    type = R_NUMBER;
	    dummy = R2N(Root->Child[1]->Result);
	    if (dummy == 0) {
		error("Evaluator: warning: division by zero");
		number = 0.0;
	    } else {
		number = R2N(Root->Child[0]->Result) / R2N(Root->Child[1]->Result);
	    }
	    break;

	case O_MOD:		/* modulo */
	    type = R_NUMBER;
	    dummy = R2N(Root->Child[1]->Result);
	    if (dummy == 0) {
		error("Evaluator: warning: division by zero");
		number = 0.0;
	    } else {
		number = fmod(R2N(Root->Child[0]->Result), R2N(Root->Child[1]->Result));
	    }
	    break;

	case O_POW:		/* x^y */
	    type = R_NUMBER;
	    number = pow(R2N(Root->Child[0]->Result), R2N(Root->Child[1]->Result));
	    break;

	case O_NOT:		/* logical NOT */
	    type = R_NUMBER;
	    number = (R2N(Root->Child[0]->Result) == 0.0);
	    break;

	default:
	    error("Evaluator: internal error: unhandled operator <%d>", Root->Operator);
	    SetResult(&Root->Result, R_STRING, "");
	    return -1;
	}

	if (type == R_NUMBER) {
	    SetResult(&Root->Result, R_NUMBER, &number);
	    return 0;
	}
	if (type == R_STRING) {
	    SetResult(&Root->Result, R_STRING, string);
	    if (freeme)
		free(string);
	    return 0;
	}
	error("Evaluator: internal error: unhandled type <%d>", type);
	SetResult(&Root->Result, R_STRING, "");
	return -1;

    default:
	error("Evaluator: internal error: unhandled token <%d>", Root->Token);
	SetResult(&Root->Result, R_STRING, "");
	return -1;

    }

    return 0;
}


int Compile(const char *expression, void **tree)
{
    NODE *Root;

    *tree = NULL;

    Expression = (char *) expression;
    ExprPtr = Expression;

    Parse();
    if (*Word == '\0') {
	/* error ("Evaluator: empty expression <%s>", Expression); */
	free(Word);
	Word = NULL;
	return -1;
    }

    Root = Level01();

    if (*Word != '\0') {
	error("Evaluator: syntax error in <%s>: garbage <%s>", Expression, Word);
	free(Word);
	Word = NULL;
	return -1;
    }

    free(Word);
    Word = NULL;

    *(NODE **) tree = Root;

    return 0;
}


int Eval(void *tree, RESULT * result)
{
    int ret;
    NODE *Tree = (NODE *) tree;

    DelResult(result);

    if (Tree == NULL) {
	SetResult(&result, R_STRING, "");
	return 0;
    }

    ret = EvalTree(Tree);

    result->type = Tree->Result->type;
    result->number = Tree->Result->number;
    result->length = Tree->Result->length;
    if (result->length >= 0) {
	result->string = malloc(result->length);
	if (Tree->Result->string != NULL)
	    strcpy(result->string, Tree->Result->string);
	else
	    result->string[0] = '\0';
    } else {
	result->string = NULL;
    }

    return ret;
}


void DelTree(void *tree)
{
    int i;
    NODE *Tree = (NODE *) tree;

    if (Tree == NULL)
	return;

    for (i = 0; i < Tree->Children; i++) {
	DelTree(Tree->Child[i]);
    }

    if (Tree->Result)
	FreeResult(Tree->Result);
    free(Tree);
}