LWTools Old Repo: lwlib/lw

annotate lwlib/lw_expr.c @ 346:a82c55070624

Added expression parsing infrastructure and misc fixes

author	lost@starbug
date	Sat, 27 Mar 2010 19:04:03 -0600
parents	7b4123dce741
children	1649bc7bda5a

rev	line source
334 f2173d18c73f Checkpoint lost parents: diff changeset	1 /*
f2173d18c73f Checkpoint lost parents: diff changeset	2 lwexpr.c
f2173d18c73f Checkpoint lost parents: diff changeset	3
f2173d18c73f Checkpoint lost parents: diff changeset	4 Copyright © 2010 William Astle
f2173d18c73f Checkpoint lost parents: diff changeset	5
f2173d18c73f Checkpoint lost parents: diff changeset	6 This file is part of LWTOOLS.
f2173d18c73f Checkpoint lost parents: diff changeset	7
f2173d18c73f Checkpoint lost parents: diff changeset	8 LWTOOLS is free software: you can redistribute it and/or modify it under the
f2173d18c73f Checkpoint lost parents: diff changeset	9 terms of the GNU General Public License as published by the Free Software
f2173d18c73f Checkpoint lost parents: diff changeset	10 Foundation, either version 3 of the License, or (at your option) any later
f2173d18c73f Checkpoint lost parents: diff changeset	11 version.
f2173d18c73f Checkpoint lost parents: diff changeset	12
f2173d18c73f Checkpoint lost parents: diff changeset	13 This program is distributed in the hope that it will be useful, but WITHOUT
f2173d18c73f Checkpoint lost parents: diff changeset	14 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
f2173d18c73f Checkpoint lost parents: diff changeset	15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
f2173d18c73f Checkpoint lost parents: diff changeset	16 more details.
f2173d18c73f Checkpoint lost parents: diff changeset	17
f2173d18c73f Checkpoint lost parents: diff changeset	18 You should have received a copy of the GNU General Public License along with
f2173d18c73f Checkpoint lost parents: diff changeset	19 this program. If not, see <http://www.gnu.org/licenses/>.
f2173d18c73f Checkpoint lost parents: diff changeset	20 */
f2173d18c73f Checkpoint lost parents: diff changeset	21
f2173d18c73f Checkpoint lost parents: diff changeset	22 #include <config.h>
f2173d18c73f Checkpoint lost parents: diff changeset	23
f2173d18c73f Checkpoint lost parents: diff changeset	24 #include <stdarg.h>
f2173d18c73f Checkpoint lost parents: diff changeset	25 #include <stdio.h>
f2173d18c73f Checkpoint lost parents: diff changeset	26 #include <string.h>
f2173d18c73f Checkpoint lost parents: diff changeset	27
f2173d18c73f Checkpoint lost parents: diff changeset	28 #define ___lw_expr_c_seen___
f2173d18c73f Checkpoint lost parents: diff changeset	29 #include "lw_alloc.h"
f2173d18c73f Checkpoint lost parents: diff changeset	30 #include "lw_expr.h"
f2173d18c73f Checkpoint lost parents: diff changeset	31 #include "lw_error.h"
f2173d18c73f Checkpoint lost parents: diff changeset	32 #include "lw_string.h"
f2173d18c73f Checkpoint lost parents: diff changeset	33
342 7b4123dce741 Added basic symbol registration lost@starbug parents: 337 diff changeset	34 static lw_expr_fn_t *evaluate_special = NULL;
7b4123dce741 Added basic symbol registration lost@starbug parents: 337 diff changeset	35 static lw_expr_fn2_t *evaluate_var = NULL;
346 a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	36 static lw_expr_fn3_t *parse_term = NULL;
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	37
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	38 void lw_expr_set_term_parser(lw_expr_fn3_t *fn)
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	39 {
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	40 parse_term = fn;
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	41 }
337 04c80c51b16a Checkpoint development lost parents: 336 diff changeset	42
342 7b4123dce741 Added basic symbol registration lost@starbug parents: 337 diff changeset	43 void lw_expr_set_special_handler(lw_expr_fn_t *fn)
337 04c80c51b16a Checkpoint development lost parents: 336 diff changeset	44 {
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	45 evaluate_special = fn;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	46 }
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	47
342 7b4123dce741 Added basic symbol registration lost@starbug parents: 337 diff changeset	48 void lw_expr_set_var_handler(lw_expr_fn2_t *fn)
337 04c80c51b16a Checkpoint development lost parents: 336 diff changeset	49 {
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	50 evaluate_var = fn;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	51 }
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	52
334 f2173d18c73f Checkpoint lost parents: diff changeset	53 lw_expr_t lw_expr_create(void)
f2173d18c73f Checkpoint lost parents: diff changeset	54 {
f2173d18c73f Checkpoint lost parents: diff changeset	55 lw_expr_t r;
f2173d18c73f Checkpoint lost parents: diff changeset	56
f2173d18c73f Checkpoint lost parents: diff changeset	57 r = lw_alloc(sizeof(struct lw_expr_priv));
f2173d18c73f Checkpoint lost parents: diff changeset	58 r -> operands = NULL;
f2173d18c73f Checkpoint lost parents: diff changeset	59
f2173d18c73f Checkpoint lost parents: diff changeset	60 return r;
f2173d18c73f Checkpoint lost parents: diff changeset	61 }
f2173d18c73f Checkpoint lost parents: diff changeset	62
f2173d18c73f Checkpoint lost parents: diff changeset	63 void lw_expr_destroy(lw_expr_t E)
f2173d18c73f Checkpoint lost parents: diff changeset	64 {
337 04c80c51b16a Checkpoint development lost parents: 336 diff changeset	65 struct lw_expr_opers *o;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	66 for (o = E -> operands; o; o = o -> next)
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	67 lw_expr_destroy(o -> p);
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	68 if (E -> type == lw_expr_type_var)
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	69 lw_free(E -> value2);
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	70 lw_free(E);
334 f2173d18c73f Checkpoint lost parents: diff changeset	71 }
f2173d18c73f Checkpoint lost parents: diff changeset	72
337 04c80c51b16a Checkpoint development lost parents: 336 diff changeset	73 /* actually duplicates the entire expression */
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	74 void lw_expr_add_operand(lw_expr_t E, lw_expr_t O);
334 f2173d18c73f Checkpoint lost parents: diff changeset	75 lw_expr_t lw_expr_copy(lw_expr_t E)
f2173d18c73f Checkpoint lost parents: diff changeset	76 {
337 04c80c51b16a Checkpoint development lost parents: 336 diff changeset	77 lw_expr_t r, t;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	78 struct lw_expr_opers *o;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	79
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	80 r = lw_alloc(sizeof(struct lw_expr_priv));
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	81 r = E;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	82 r -> operands = NULL;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	83
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	84 if (E -> type == lw_expr_type_var)
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	85 r -> value2 = lw_strdup(E -> value2);
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	86 for (o = E -> operands; o; o = o -> next)
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	87 {
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	88 lw_expr_add_operand(r, lw_expr_copy(o -> p));
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	89 }
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	90
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	91 return r;
334 f2173d18c73f Checkpoint lost parents: diff changeset	92 }
f2173d18c73f Checkpoint lost parents: diff changeset	93
f2173d18c73f Checkpoint lost parents: diff changeset	94 void lw_expr_add_operand(lw_expr_t E, lw_expr_t O)
f2173d18c73f Checkpoint lost parents: diff changeset	95 {
f2173d18c73f Checkpoint lost parents: diff changeset	96 struct lw_expr_opers o, t;
f2173d18c73f Checkpoint lost parents: diff changeset	97
f2173d18c73f Checkpoint lost parents: diff changeset	98 o = lw_alloc(sizeof(struct lw_expr_opers));
f2173d18c73f Checkpoint lost parents: diff changeset	99 o -> p = lw_expr_copy(O);
f2173d18c73f Checkpoint lost parents: diff changeset	100 o -> next = NULL;
f2173d18c73f Checkpoint lost parents: diff changeset	101 for (t = E -> operands; t && t -> next; t = t -> next)
f2173d18c73f Checkpoint lost parents: diff changeset	102 /* do nothing */ ;
f2173d18c73f Checkpoint lost parents: diff changeset	103
f2173d18c73f Checkpoint lost parents: diff changeset	104 if (t)
f2173d18c73f Checkpoint lost parents: diff changeset	105 t -> next = o;
f2173d18c73f Checkpoint lost parents: diff changeset	106 else
f2173d18c73f Checkpoint lost parents: diff changeset	107 E -> operands = o;
f2173d18c73f Checkpoint lost parents: diff changeset	108 }
f2173d18c73f Checkpoint lost parents: diff changeset	109
335 9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	110 lw_expr_t lw_expr_build_aux(int exprtype, va_list args)
334 f2173d18c73f Checkpoint lost parents: diff changeset	111 {
f2173d18c73f Checkpoint lost parents: diff changeset	112 lw_expr_t r;
f2173d18c73f Checkpoint lost parents: diff changeset	113 int t;
f2173d18c73f Checkpoint lost parents: diff changeset	114 void *p;
f2173d18c73f Checkpoint lost parents: diff changeset	115
f2173d18c73f Checkpoint lost parents: diff changeset	116 lw_expr_t te1, te2;
f2173d18c73f Checkpoint lost parents: diff changeset	117
f2173d18c73f Checkpoint lost parents: diff changeset	118 r = lw_expr_create();
f2173d18c73f Checkpoint lost parents: diff changeset	119
f2173d18c73f Checkpoint lost parents: diff changeset	120 switch (exprtype)
f2173d18c73f Checkpoint lost parents: diff changeset	121 {
f2173d18c73f Checkpoint lost parents: diff changeset	122 case lw_expr_type_int:
f2173d18c73f Checkpoint lost parents: diff changeset	123 t = va_arg(args, int);
f2173d18c73f Checkpoint lost parents: diff changeset	124 r -> type = lw_expr_type_int;
f2173d18c73f Checkpoint lost parents: diff changeset	125 r -> value = t;
f2173d18c73f Checkpoint lost parents: diff changeset	126 break;
f2173d18c73f Checkpoint lost parents: diff changeset	127
f2173d18c73f Checkpoint lost parents: diff changeset	128 case lw_expr_type_var:
f2173d18c73f Checkpoint lost parents: diff changeset	129 p = va_arg(args, char *);
f2173d18c73f Checkpoint lost parents: diff changeset	130 r -> type = lw_expr_type_var;
f2173d18c73f Checkpoint lost parents: diff changeset	131 r -> value2 = lw_strdup(p);
f2173d18c73f Checkpoint lost parents: diff changeset	132 break;
f2173d18c73f Checkpoint lost parents: diff changeset	133
f2173d18c73f Checkpoint lost parents: diff changeset	134 case lw_expr_type_special:
f2173d18c73f Checkpoint lost parents: diff changeset	135 t = va_arg(args, int);
f2173d18c73f Checkpoint lost parents: diff changeset	136 p = va_arg(args, char *);
f2173d18c73f Checkpoint lost parents: diff changeset	137 r -> type = lw_expr_type_special;
337 04c80c51b16a Checkpoint development lost parents: 336 diff changeset	138 r -> value = t;
334 f2173d18c73f Checkpoint lost parents: diff changeset	139 r -> value2 = p;
f2173d18c73f Checkpoint lost parents: diff changeset	140 break;
f2173d18c73f Checkpoint lost parents: diff changeset	141
f2173d18c73f Checkpoint lost parents: diff changeset	142 case lw_expr_type_oper:
f2173d18c73f Checkpoint lost parents: diff changeset	143 t = va_arg(args, int);
f2173d18c73f Checkpoint lost parents: diff changeset	144 te1 = va_arg(args, lw_expr_t);
f2173d18c73f Checkpoint lost parents: diff changeset	145 if (t != lw_expr_oper_com && t != lw_expr_oper_neg)
f2173d18c73f Checkpoint lost parents: diff changeset	146 te2 = va_arg(args, lw_expr_t);
f2173d18c73f Checkpoint lost parents: diff changeset	147 else
f2173d18c73f Checkpoint lost parents: diff changeset	148 te2 = NULL;
f2173d18c73f Checkpoint lost parents: diff changeset	149
f2173d18c73f Checkpoint lost parents: diff changeset	150 r -> type = lw_expr_type_oper;
f2173d18c73f Checkpoint lost parents: diff changeset	151 r -> value = t;
f2173d18c73f Checkpoint lost parents: diff changeset	152 lw_expr_add_operand(r, te1);
f2173d18c73f Checkpoint lost parents: diff changeset	153 lw_expr_add_operand(r, te2);
f2173d18c73f Checkpoint lost parents: diff changeset	154 break;
f2173d18c73f Checkpoint lost parents: diff changeset	155
f2173d18c73f Checkpoint lost parents: diff changeset	156 default:
f2173d18c73f Checkpoint lost parents: diff changeset	157 lw_error("Invalid expression type specified to lw_expr_build");
f2173d18c73f Checkpoint lost parents: diff changeset	158 }
f2173d18c73f Checkpoint lost parents: diff changeset	159
335 9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	160 return r;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	161 }
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	162
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	163 lw_expr_t lw_expr_build(int exprtype, ...)
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	164 {
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	165 va_list args;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	166 lw_expr_t r;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	167
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	168 va_start(args, exprtype);
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	169 r = lw_expr_build_aux(exprtype, args);
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	170 va_end(args);
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	171 return r;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	172 }
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	173
334 f2173d18c73f Checkpoint lost parents: diff changeset	174 void lw_expr_print(lw_expr_t E)
f2173d18c73f Checkpoint lost parents: diff changeset	175 {
f2173d18c73f Checkpoint lost parents: diff changeset	176 struct lw_expr_opers *o;
335 9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	177 int c = 0;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	178
334 f2173d18c73f Checkpoint lost parents: diff changeset	179 for (o = E -> operands; o; o = o -> next)
f2173d18c73f Checkpoint lost parents: diff changeset	180 {
335 9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	181 c++;
334 f2173d18c73f Checkpoint lost parents: diff changeset	182 lw_expr_print(o -> p);
f2173d18c73f Checkpoint lost parents: diff changeset	183 }
f2173d18c73f Checkpoint lost parents: diff changeset	184
f2173d18c73f Checkpoint lost parents: diff changeset	185 switch (E -> type)
f2173d18c73f Checkpoint lost parents: diff changeset	186 {
f2173d18c73f Checkpoint lost parents: diff changeset	187 case lw_expr_type_int:
f2173d18c73f Checkpoint lost parents: diff changeset	188 printf("%d ", E -> value);
f2173d18c73f Checkpoint lost parents: diff changeset	189 break;
335 9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	190
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	191 case lw_expr_type_var:
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	192 printf("V(%s) ", (char *)(E -> value2));
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	193 break;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	194
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	195 case lw_expr_type_special:
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	196 printf("S(%d,%p) ", E -> value, E -> value2);
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	197 break;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	198
334 f2173d18c73f Checkpoint lost parents: diff changeset	199 case lw_expr_type_oper:
335 9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	200 printf("[%d]", c);
334 f2173d18c73f Checkpoint lost parents: diff changeset	201 switch (E -> value)
f2173d18c73f Checkpoint lost parents: diff changeset	202 {
f2173d18c73f Checkpoint lost parents: diff changeset	203 case lw_expr_oper_plus:
f2173d18c73f Checkpoint lost parents: diff changeset	204 printf("+ ");
f2173d18c73f Checkpoint lost parents: diff changeset	205 break;
f2173d18c73f Checkpoint lost parents: diff changeset	206
f2173d18c73f Checkpoint lost parents: diff changeset	207 case lw_expr_oper_minus:
f2173d18c73f Checkpoint lost parents: diff changeset	208 printf("- ");
f2173d18c73f Checkpoint lost parents: diff changeset	209 break;
f2173d18c73f Checkpoint lost parents: diff changeset	210
f2173d18c73f Checkpoint lost parents: diff changeset	211 case lw_expr_oper_times:
f2173d18c73f Checkpoint lost parents: diff changeset	212 printf("* ");
f2173d18c73f Checkpoint lost parents: diff changeset	213 break;
f2173d18c73f Checkpoint lost parents: diff changeset	214
f2173d18c73f Checkpoint lost parents: diff changeset	215 case lw_expr_oper_divide:
f2173d18c73f Checkpoint lost parents: diff changeset	216 printf("/ ");
f2173d18c73f Checkpoint lost parents: diff changeset	217 break;
f2173d18c73f Checkpoint lost parents: diff changeset	218
f2173d18c73f Checkpoint lost parents: diff changeset	219 case lw_expr_oper_mod:
f2173d18c73f Checkpoint lost parents: diff changeset	220 printf("%% ");
f2173d18c73f Checkpoint lost parents: diff changeset	221 break;
f2173d18c73f Checkpoint lost parents: diff changeset	222
f2173d18c73f Checkpoint lost parents: diff changeset	223 case lw_expr_oper_intdiv:
f2173d18c73f Checkpoint lost parents: diff changeset	224 printf("\\ ");
f2173d18c73f Checkpoint lost parents: diff changeset	225 break;
f2173d18c73f Checkpoint lost parents: diff changeset	226
f2173d18c73f Checkpoint lost parents: diff changeset	227 case lw_expr_oper_bwand:
f2173d18c73f Checkpoint lost parents: diff changeset	228 printf("BWAND ");
f2173d18c73f Checkpoint lost parents: diff changeset	229 break;
f2173d18c73f Checkpoint lost parents: diff changeset	230
f2173d18c73f Checkpoint lost parents: diff changeset	231 case lw_expr_oper_bwor:
f2173d18c73f Checkpoint lost parents: diff changeset	232 printf("BWOR ");
f2173d18c73f Checkpoint lost parents: diff changeset	233 break;
f2173d18c73f Checkpoint lost parents: diff changeset	234
f2173d18c73f Checkpoint lost parents: diff changeset	235 case lw_expr_oper_bwxor:
f2173d18c73f Checkpoint lost parents: diff changeset	236 printf("BWXOR ");
f2173d18c73f Checkpoint lost parents: diff changeset	237 break;
f2173d18c73f Checkpoint lost parents: diff changeset	238
f2173d18c73f Checkpoint lost parents: diff changeset	239 case lw_expr_oper_and:
f2173d18c73f Checkpoint lost parents: diff changeset	240 printf("AND ");
f2173d18c73f Checkpoint lost parents: diff changeset	241 break;
f2173d18c73f Checkpoint lost parents: diff changeset	242
f2173d18c73f Checkpoint lost parents: diff changeset	243 case lw_expr_oper_or:
f2173d18c73f Checkpoint lost parents: diff changeset	244 printf("OR ");
f2173d18c73f Checkpoint lost parents: diff changeset	245 break;
f2173d18c73f Checkpoint lost parents: diff changeset	246
f2173d18c73f Checkpoint lost parents: diff changeset	247 case lw_expr_oper_neg:
f2173d18c73f Checkpoint lost parents: diff changeset	248 printf("NEG ");
f2173d18c73f Checkpoint lost parents: diff changeset	249 break;
f2173d18c73f Checkpoint lost parents: diff changeset	250
f2173d18c73f Checkpoint lost parents: diff changeset	251 case lw_expr_oper_com:
f2173d18c73f Checkpoint lost parents: diff changeset	252 printf("COM ");
f2173d18c73f Checkpoint lost parents: diff changeset	253 break;
f2173d18c73f Checkpoint lost parents: diff changeset	254
f2173d18c73f Checkpoint lost parents: diff changeset	255 default:
f2173d18c73f Checkpoint lost parents: diff changeset	256 printf("OPER ");
f2173d18c73f Checkpoint lost parents: diff changeset	257 break;
f2173d18c73f Checkpoint lost parents: diff changeset	258 }
f2173d18c73f Checkpoint lost parents: diff changeset	259 break;
f2173d18c73f Checkpoint lost parents: diff changeset	260 default:
f2173d18c73f Checkpoint lost parents: diff changeset	261 printf("ERR ");
f2173d18c73f Checkpoint lost parents: diff changeset	262 break;
f2173d18c73f Checkpoint lost parents: diff changeset	263 }
f2173d18c73f Checkpoint lost parents: diff changeset	264 }
f2173d18c73f Checkpoint lost parents: diff changeset	265
f2173d18c73f Checkpoint lost parents: diff changeset	266 /*
f2173d18c73f Checkpoint lost parents: diff changeset	267 Return:
f2173d18c73f Checkpoint lost parents: diff changeset	268 nonzero if expressions are the same (identical pointers or matching values)
f2173d18c73f Checkpoint lost parents: diff changeset	269 zero if expressions are not the same
f2173d18c73f Checkpoint lost parents: diff changeset	270
f2173d18c73f Checkpoint lost parents: diff changeset	271 */
f2173d18c73f Checkpoint lost parents: diff changeset	272 int lw_expr_compare(lw_expr_t E1, lw_expr_t E2)
f2173d18c73f Checkpoint lost parents: diff changeset	273 {
f2173d18c73f Checkpoint lost parents: diff changeset	274 struct lw_expr_opers o1, o2;
f2173d18c73f Checkpoint lost parents: diff changeset	275
f2173d18c73f Checkpoint lost parents: diff changeset	276 if (E1 == E2)
f2173d18c73f Checkpoint lost parents: diff changeset	277 return 1;
f2173d18c73f Checkpoint lost parents: diff changeset	278
f2173d18c73f Checkpoint lost parents: diff changeset	279 if (!(E1 -> type == E2 -> type && E1 -> value == E2 -> value))
f2173d18c73f Checkpoint lost parents: diff changeset	280 return 0;
f2173d18c73f Checkpoint lost parents: diff changeset	281
f2173d18c73f Checkpoint lost parents: diff changeset	282 if (E1 -> type == lw_expr_type_var)
f2173d18c73f Checkpoint lost parents: diff changeset	283 {
f2173d18c73f Checkpoint lost parents: diff changeset	284 if (!strcmp(E1 -> value2, E2 -> value2))
f2173d18c73f Checkpoint lost parents: diff changeset	285 return 1;
f2173d18c73f Checkpoint lost parents: diff changeset	286 else
f2173d18c73f Checkpoint lost parents: diff changeset	287 return 0;
f2173d18c73f Checkpoint lost parents: diff changeset	288 }
f2173d18c73f Checkpoint lost parents: diff changeset	289
f2173d18c73f Checkpoint lost parents: diff changeset	290 if (E1 -> type == lw_expr_type_special)
f2173d18c73f Checkpoint lost parents: diff changeset	291 {
f2173d18c73f Checkpoint lost parents: diff changeset	292 if (E1 -> value2 == E2 -> value2)
f2173d18c73f Checkpoint lost parents: diff changeset	293 return 1;
f2173d18c73f Checkpoint lost parents: diff changeset	294 else
f2173d18c73f Checkpoint lost parents: diff changeset	295 return 0;
f2173d18c73f Checkpoint lost parents: diff changeset	296 }
f2173d18c73f Checkpoint lost parents: diff changeset	297
f2173d18c73f Checkpoint lost parents: diff changeset	298 for (o1 = E1 -> operands, o2 = E2 -> operands; o1 && o2; o1 = o1 -> next, o2 = o2 -> next)
f2173d18c73f Checkpoint lost parents: diff changeset	299 if (lw_expr_compare(o1 -> p, o2 -> p) == 0)
f2173d18c73f Checkpoint lost parents: diff changeset	300 return 0;
f2173d18c73f Checkpoint lost parents: diff changeset	301 if (o1 \|\| o2)
f2173d18c73f Checkpoint lost parents: diff changeset	302 return 0;
f2173d18c73f Checkpoint lost parents: diff changeset	303
f2173d18c73f Checkpoint lost parents: diff changeset	304 return 1;
f2173d18c73f Checkpoint lost parents: diff changeset	305 }
f2173d18c73f Checkpoint lost parents: diff changeset	306
f2173d18c73f Checkpoint lost parents: diff changeset	307 /* return true if E is an operator of type oper */
f2173d18c73f Checkpoint lost parents: diff changeset	308 int lw_expr_isoper(lw_expr_t E, int oper)
f2173d18c73f Checkpoint lost parents: diff changeset	309 {
f2173d18c73f Checkpoint lost parents: diff changeset	310 if (E -> type == lw_expr_type_oper && E -> value == oper)
f2173d18c73f Checkpoint lost parents: diff changeset	311 return 1;
f2173d18c73f Checkpoint lost parents: diff changeset	312 return 0;
f2173d18c73f Checkpoint lost parents: diff changeset	313 }
335 9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	314
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	315
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	316 void lw_expr_simplify_sortconstfirst(lw_expr_t E)
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	317 {
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	318 struct lw_expr_opers *o;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	319
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	320 for (o = E -> operands; o; o = o -> next)
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	321 lw_expr_simplify_sortconstfirst(o -> p);
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	322
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	323 for (o = E -> operands; o; o = o -> next)
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	324 {
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	325 if (o -> p -> type == lw_expr_type_int && o != E -> operands)
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	326 {
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	327 struct lw_expr_opers *o2;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	328 for (o2 = E -> operands; o2 -> next != o; o2 = o2 -> next)
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	329 /* do nothing */ ;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	330 o2 -> next = o -> next;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	331 o -> next = E -> operands;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	332 E -> operands = o;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	333 o = o2;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	334 }
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	335 }
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	336 }
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	337
336 401587ab6a09 checkpoint lost parents: 335 diff changeset	338 void lw_expr_sortoperandlist(struct lw_expr_opers **o)
401587ab6a09 checkpoint lost parents: 335 diff changeset	339 {
401587ab6a09 checkpoint lost parents: 335 diff changeset	340 fprintf(stderr, "lw_expr_sortoperandlist() not yet implemented\n");
401587ab6a09 checkpoint lost parents: 335 diff changeset	341 }
401587ab6a09 checkpoint lost parents: 335 diff changeset	342
335 9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	343 // return 1 if the operand lists match, 0 if not
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	344 // may re-order the argument lists
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	345 int lw_expr_simplify_compareoperandlist(struct lw_expr_opers ol1, struct lw_expr_opers ol2)
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	346 {
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	347 struct lw_expr_opers o1, o2;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	348
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	349 lw_expr_sortoperandlist(ol1);
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	350 lw_expr_sortoperandlist(ol2);
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	351
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	352 for (o1 = ol1, o2 = ol2; o1 && o2; o1 = o1 -> next, o2 = o2 -> next)
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	353 {
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	354 if (!lw_expr_compare(o1 -> p, o2 -> p))
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	355 return 0;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	356 }
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	357 if (o1 \|\| o2)
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	358 return 0;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	359 return 1;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	360 }
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	361
346 a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	362 void lw_expr_simplify(lw_expr_t E, void *priv)
335 9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	363 {
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	364 struct lw_expr_opers *o;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	365
337 04c80c51b16a Checkpoint development lost parents: 336 diff changeset	366 again:
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	367 // try to resolve non-constant terms to constants here
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	368 if (E -> type == lw_expr_type_special && evaluate_special)
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	369 {
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	370 lw_expr_t te;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	371
346 a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	372 te = evaluate_special(E -> value, E -> value2, priv);
337 04c80c51b16a Checkpoint development lost parents: 336 diff changeset	373 if (te)
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	374 {
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	375 for (o = E -> operands; o; o = o -> next)
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	376 lw_expr_destroy(o -> p);
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	377 if (E -> type == lw_expr_type_var)
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	378 lw_free(E -> value2);
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	379 E = te;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	380 E -> operands = NULL;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	381
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	382 if (te -> type == lw_expr_type_var)
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	383 E -> value2 = lw_strdup(te -> value2);
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	384 for (o = te -> operands; o; o = o -> next)
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	385 {
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	386 lw_expr_add_operand(E, lw_expr_copy(o -> p));
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	387 }
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	388 lw_expr_destroy(te);
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	389 goto again;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	390 }
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	391 return;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	392 }
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	393
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	394 if (E -> type == lw_expr_type_var && evaluate_var)
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	395 {
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	396 lw_expr_t te;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	397
346 a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	398 te = evaluate_var(E -> value2, priv);
337 04c80c51b16a Checkpoint development lost parents: 336 diff changeset	399 if (te)
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	400 {
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	401 for (o = E -> operands; o; o = o -> next)
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	402 lw_expr_destroy(o -> p);
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	403 if (E -> type == lw_expr_type_var)
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	404 lw_free(E -> value2);
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	405 E = te;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	406 E -> operands = NULL;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	407
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	408 if (te -> type == lw_expr_type_var)
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	409 E -> value2 = lw_strdup(te -> value2);
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	410 for (o = te -> operands; o; o = o -> next)
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	411 {
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	412 lw_expr_add_operand(E, lw_expr_copy(o -> p));
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	413 }
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	414 lw_expr_destroy(te);
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	415 goto again;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	416 }
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	417 return;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	418 }
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	419
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	420 // non-operators have no simplification to do!
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	421 if (E -> type != lw_expr_type_oper)
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	422 return;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	423
335 9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	424 // sort "constants" to the start of each operand list for + and *
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	425 lw_expr_simplify_sortconstfirst(E);
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	426
337 04c80c51b16a Checkpoint development lost parents: 336 diff changeset	427 // simplify operands
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	428 for (o = E -> operands; o; o = o -> next)
346 a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	429 lw_expr_simplify(o -> p, priv);
337 04c80c51b16a Checkpoint development lost parents: 336 diff changeset	430
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	431 for (o = E -> operands; o; o = o -> next)
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	432 {
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	433 if (o -> p -> type != lw_expr_type_int)
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	434 break;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	435 }
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	436
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	437 if (!o)
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	438 {
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	439 // we can do the operation here!
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	440 int tr = -42424242;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	441
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	442 switch (E -> value)
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	443 {
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	444 case lw_expr_oper_neg:
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	445 tr = -(E -> operands -> p -> value);
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	446 break;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	447
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	448 case lw_expr_oper_com:
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	449 tr = ~(E -> operands -> p -> value);
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	450 break;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	451
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	452 case lw_expr_oper_plus:
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	453 tr = E -> operands -> p -> value;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	454 for (o = E -> operands -> next; o; o = o -> next)
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	455 tr += o -> p -> value;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	456 break;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	457
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	458 case lw_expr_oper_minus:
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	459 tr = E -> operands -> p -> value;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	460 for (o = E -> operands -> next; o; o = o -> next)
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	461 tr -= o -> p -> value;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	462 break;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	463
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	464 case lw_expr_oper_times:
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	465 tr = E -> operands -> p -> value;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	466 for (o = E -> operands -> next; o; o = o -> next)
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	467 tr *= o -> p -> value;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	468 break;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	469
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	470 case lw_expr_oper_divide:
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	471 tr = E -> operands -> p -> value / E -> operands -> next -> p -> value;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	472 break;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	473
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	474 case lw_expr_oper_mod:
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	475 tr = E -> operands -> p -> value % E -> operands -> next -> p -> value;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	476 break;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	477
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	478 case lw_expr_oper_intdiv:
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	479 tr = E -> operands -> p -> value / E -> operands -> next -> p -> value;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	480 break;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	481
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	482 case lw_expr_oper_bwand:
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	483 tr = E -> operands -> p -> value & E -> operands -> next -> p -> value;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	484 break;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	485
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	486 case lw_expr_oper_bwor:
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	487 tr = E -> operands -> p -> value \| E -> operands -> next -> p -> value;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	488 break;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	489
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	490 case lw_expr_oper_bwxor:
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	491 tr = E -> operands -> p -> value ^ E -> operands -> next -> p -> value;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	492 break;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	493
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	494 case lw_expr_oper_and:
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	495 tr = E -> operands -> p -> value && E -> operands -> next -> p -> value;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	496 break;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	497
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	498 case lw_expr_oper_or:
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	499 tr = E -> operands -> p -> value \|\| E -> operands -> next -> p -> value;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	500 break;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	501
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	502 }
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	503
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	504 while (E -> operands)
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	505 {
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	506 o = E -> operands;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	507 E -> operands = o -> next;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	508 lw_expr_destroy(o -> p);
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	509 lw_free(o);
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	510 }
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	511 E -> type = lw_expr_type_int;
04c80c51b16a Checkpoint development lost parents: 336 diff changeset	512 E -> value = tr;
335 9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	513 return;
337 04c80c51b16a Checkpoint development lost parents: 336 diff changeset	514 }
335 9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	515
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	516 if (E -> value == lw_expr_oper_times)
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	517 {
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	518 for (o = E -> operands; o; o = o -> next)
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	519 {
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	520 if (o -> p -> type == lw_expr_type_int && o -> p -> value == 0)
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	521 {
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	522 // one operand of times is 0, replace operation with 0
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	523 while (E -> operands)
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	524 {
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	525 o = E -> operands;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	526 E -> operands = o -> next;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	527 lw_expr_destroy(o -> p);
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	528 lw_free(o);
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	529 }
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	530 E -> type = lw_expr_type_int;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	531 E -> value = 0;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	532 return;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	533 }
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	534 }
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	535 }
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	536
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	537 // look for like terms and collect them together
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	538 if (E -> value == lw_expr_oper_plus)
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	539 {
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	540 for (o = E -> operands; o; o = o -> next)
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	541 {
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	542 if (o -> p -> type == lw_expr_type_oper && o -> p -> value == lw_expr_oper_times)
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	543 {
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	544 // we have a "times" here
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	545 // find first non-const operand
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	546 struct lw_expr_opers op1, op2, *o2;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	547 for (op1 = o -> p -> operands; op1; op1 = op1 -> next)
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	548 if (op1 -> p -> type != lw_expr_type_int)
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	549 break;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	550
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	551 for (o2 = o -> next; o2; o2 = o2 -> next)
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	552 {
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	553 if (o2 -> p -> type == lw_expr_type_oper && o2 -> p -> value == lw_expr_oper_times)
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	554 {
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	555 // another "times"
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	556 for (op2 = o2 -> p -> operands; op2; op2 = op2 -> next)
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	557 if (op2 -> p -> type != lw_expr_type_int)
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	558 break;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	559
336 401587ab6a09 checkpoint lost parents: 335 diff changeset	560 if (lw_expr_simplify_compareoperandlist(&op1, &op2))
335 9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	561 {
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	562 // we have like terms here
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	563 // do something about it
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	564 }
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	565 }
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	566 }
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	567 }
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	568 }
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	569 }
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	570
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	571
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	572 if (E -> value == lw_expr_oper_plus)
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	573 {
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	574 int c = 0, t = 0;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	575 for (o = E -> operands; o; o = o -> next)
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	576 {
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	577 t++;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	578 if (!(o -> p -> type == lw_expr_type_int && o -> p -> value == 0))
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	579 {
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	580 c++;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	581 }
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	582 }
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	583 if (c == 1)
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	584 {
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	585 lw_expr_t r;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	586 // find the value and "move it up"
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	587 while (E -> operands)
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	588 {
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	589 o = E -> operands;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	590 if (o -> p -> type != lw_expr_type_int \|\| o -> p -> value != 0)
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	591 {
337 04c80c51b16a Checkpoint development lost parents: 336 diff changeset	592 r = lw_expr_copy(o -> p);
335 9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	593 }
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	594 E -> operands = o -> next;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	595 lw_expr_destroy(o -> p);
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	596 lw_free(o);
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	597 }
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	598 E = r;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	599 return;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	600 }
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	601 else if (c == 0)
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	602 {
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	603 // replace with 0
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	604 while (E -> operands)
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	605 {
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	606 o = E -> operands;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	607 E -> operands = o -> next;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	608 lw_expr_destroy(o -> p);
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	609 lw_free(o);
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	610 }
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	611 E -> type = lw_expr_type_int;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	612 E -> value = 0;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	613 return;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	614 }
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	615 else if (c != t)
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	616 {
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	617 // collapse out zero terms
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	618 struct lw_expr_opers *o2;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	619
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	620 for (o = E -> operands; o; o = o -> next)
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	621 {
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	622 if (o -> p -> type == lw_expr_type_int && o -> p -> value == 0)
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	623 {
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	624 if (o == E -> operands)
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	625 {
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	626 E -> operands = o -> next;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	627 lw_expr_destroy(o -> p);
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	628 lw_free(o);
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	629 o = E -> operands;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	630 }
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	631 else
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	632 {
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	633 for (o2 = E -> operands; o2 -> next == o; o2 = o2 -> next)
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	634 /* do nothing */ ;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	635 o2 -> next = o -> next;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	636 lw_expr_destroy(o -> p);
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	637 lw_free(o);
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	638 o = o2;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	639 }
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	640 }
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	641 }
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	642 }
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	643 return;
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	644 }
9f58e3bca6e3 checkpoint lost parents: 334 diff changeset	645 }
346 a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	646
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	647 /*
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	648
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	649 The following two functions are co-routines which evaluate an infix
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	650 expression. lw_expr_parse_term checks for unary prefix operators then, if
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	651 none found, passes the string off the the defined helper function to
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	652 determine what the term really is. It also handles parentheses.
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	653
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	654 lw_expr_parse_expr evaluates actual expressions with infix operators. It
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	655 respects the order of operations.
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	656
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	657 The end of an expression is determined by the presence of any of the
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	658 following conditions:
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	659
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	660 1. a NUL character
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	661 2. a whitespace character
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	662 3. a )
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	663 4. a ,
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	664 5. any character that is not recognized as a term
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	665
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	666 lw_expr_parse_term returns NULL if there is no term (end of expr, etc.)
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	667
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	668 lw_expr_parse_expr returns NULL if there is no expression or on a syntax
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	669 error.
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	670
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	671 */
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	672
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	673 lw_expr_t lw_expr_parse_expr(char *p, void priv, int prec);
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	674
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	675 lw_expr_t lw_expr_parse_term(char *p, void priv)
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	676 {
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	677 lw_expr_t term, term2;
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	678
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	679 eval_next:
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	680 if (!p \|\| isspace(p) \|\| p == ')' \|\| p == ']')
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	681 return NULL;
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	682
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	683 // parentheses
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	684 if (**p == '(')
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	685 {
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	686 (*p)++;
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	687 term = lw_expr_parse_expr(p, priv, 0);
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	688 if (**p != ')')
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	689 {
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	690 lw_expr_destroy(term);
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	691 return NULL;
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	692 }
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	693 (*p)++;
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	694 return term;
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	695 }
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	696
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	697 // unary +
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	698 if (**p == '+')
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	699 {
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	700 (*p)++;
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	701 goto eval_next;
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	702 }
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	703
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	704 // unary - (prec 200)
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	705 if (**p == '-')
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	706 {
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	707 (*p)++;
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	708 term = lw_expr_parse_expr(p, priv, 200);
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	709 if (!term)
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	710 return NULL;
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	711
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	712 term2 = lw_expr_build(lw_expr_type_oper, lw_expr_oper_neg, term);
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	713 lw_expr_destroy(term);
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	714 return term2;
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	715 }
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	716
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	717 // unary ^ or ~ (complement, prec 200)
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	718 if (p == '^' \|\| p == '~')
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	719 {
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	720 (*p)++;
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	721 term = lw_expr_parse_expr(p, priv, 200);
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	722 if (!term)
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	723 return NULL;
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	724
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	725 term2 = lw_expr_build(lw_expr_type_oper, lw_expr_oper_com, term);
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	726 lw_expr_destroy(term);
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	727 return term2;
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	728 }
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	729
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	730 // non-operator - pass to caller
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	731 return parse_term(p, priv);
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	732 }
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	733
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	734 lw_expr_t lw_expr_parse_expr(char *p, void priv, int prec)
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	735 {
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	736 static const struct operinfo
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	737 {
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	738 int opernum;
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	739 char *operstr;
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	740 int operprec;
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	741 } operators[] =
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	742 {
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	743 { lw_expr_oper_plus, "+", 100 },
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	744 { lw_expr_oper_minus, "-", 100 },
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	745 { lw_expr_oper_times, "*", 100 },
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	746 { lw_expr_oper_divide, "/", 150 },
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	747 { lw_expr_oper_mod, "%", 150 },
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	748 { lw_expr_oper_intdiv, "\\", 150 },
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	749
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	750 { lw_expr_oper_and, "&&", 25 },
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	751 { lw_expr_oper_or, "\|\|", 25 },
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	752
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	753 { lw_expr_oper_bwand, "&", 50 },
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	754 { lw_expr_oper_bwor, "\|", 50 },
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	755 { lw_expr_oper_bwxor, "^", 50 },
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	756
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	757 { lw_expr_oper_none, "", 0 }
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	758 };
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	759
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	760 int opern, i;
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	761 lw_expr_t term1, term2, term3;
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	762
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	763 if (!p \|\| isspace(p) \|\| p == ')' \|\| p == ',' \|\| **p == ']')
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	764 return NULL;
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	765
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	766 term1 = lw_expr_parse_term(p, priv);
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	767 if (!term1)
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	768 return NULL;
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	769
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	770 eval_next:
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	771 if (!p \|\| isspace(p) \|\| p == ')' \|\| p == ',' \|\| **p == ']')
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	772 return term1;
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	773
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	774 // expecting an operator here
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	775 for (opern = 0; operators[opern].opernum != lw_expr_oper_none; opern++)
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	776 {
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	777 for (i = 0; (p)[i] && operators[opern].operstr[i] && ((p)[i] == operators[opern].operstr[i]); i++)
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	778 /* do nothing */;
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	779 if (operators[opern].operstr[i] == '\0')
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	780 break;
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	781 }
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	782
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	783 if (operators[opern].opernum == lw_expr_oper_none)
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	784 {
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	785 // unrecognized operator
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	786 lw_expr_destroy(term1);
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	787 return NULL;
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	788 }
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	789
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	790 // operator number is in opern, length of oper in i
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	791
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	792 // logic:
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	793 // if the precedence of this operation is <= to the "prec" flag,
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	794 // we simply return without advancing the input pointer; the operator
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	795 // will be evaluated again in the enclosing function call
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	796 if (operators[opern].operprec <= prec)
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	797 return term1;
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	798
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	799 // logic:
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	800 // we have a higher precedence operator here so we will advance the
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	801 // input pointer to the next term and let the expression evaluator
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	802 // loose on it after which time we will push our operator onto the
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	803 // stack and then go on with the expression evaluation
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	804 (*p) += i;
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	805
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	806 // evaluate next expression(s) of higher precedence
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	807 term2 = lw_expr_parse_expr(p, priv, operators[opern].operprec);
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	808 if (!term2)
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	809 {
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	810 lw_expr_destroy(term1);
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	811 return NULL;
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	812 }
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	813
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	814 // now create operator
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	815 term3 = lw_expr_build(lw_expr_type_oper, operators[opern].opernum, term1, term2);
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	816 lw_expr_destroy(term1);
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	817 lw_expr_destroy(term2);
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	818
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	819 // the new "expression" is the next "left operand"
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	820 term1 = term3;
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	821
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	822 // continue evaluating
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	823 goto eval_next;
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	824 }
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	825
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	826 lw_expr_t lw_expr_parse(char *p, void priv)
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	827 {
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	828 return lw_expr_parse_expr(p, priv, 0);
a82c55070624 Added expression parsing infrastructure and misc fixes lost@starbug parents: 342 diff changeset	829 }

Mercurial > hg-old > index.cgi

annotate lwlib/lw_expr.c @ 346:a82c55070624