2 /* Expression parsing for plural form selection.
3 Copyright (C) 2000-2001, 2003 Free Software Foundation, Inc.
4 Written by Ulrich Drepper <drepper@cygnus.com>, 2000.
6 This program is free software; you can redistribute it and/or modify it
7 under the terms of the GNU Library General Public License as published
8 by the Free Software Foundation; either version 2, or (at your option)
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Library General Public License for more details.
16 You should have received a copy of the GNU Library General Public
17 License along with this program; if not, write to the Free Software
18 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
21 /* The bison generated parser uses alloca. AIX 3 forces us to put this
22 declaration at the beginning of the file. The declaration in bison's
23 skeleton file comes too late. This must come before <config.h>
24 because <config.h> may include arbitrary system headers. */
25 #if defined _AIX && !defined __GNUC__
35 #include "plural-exp.h"
37 /* The main function generated by the parser is called __gettextparse,
38 but we want it to be called PLURAL_PARSE. */
40 # define __gettextparse PLURAL_PARSE
43 #define YYLEX_PARAM &((struct parse_args *) arg)->cp
44 #define YYPARSE_PARAM arg
50 unsigned long int num;
52 struct expression *exp;
56 /* Prototypes for local functions. */
57 static int yylex (YYSTYPE *lval, const char **pexp);
58 static void yyerror (const char *str);
60 /* Allocation of expressions. */
62 static struct expression *
63 new_exp (int nargs, enum operator op, struct expression * const *args)
66 struct expression *newp;
68 /* If any of the argument could not be malloc'ed, just return NULL. */
69 for (i = nargs - 1; i >= 0; i--)
73 /* Allocate a new expression. */
74 newp = (struct expression *) malloc (sizeof (*newp));
79 for (i = nargs - 1; i >= 0; i--)
80 newp->val.args[i] = args[i];
85 for (i = nargs - 1; i >= 0; i--)
86 FREE_EXPRESSION (args[i]);
91 static inline struct expression *
92 new_exp_0 (enum operator op)
94 return new_exp (0, op, NULL);
97 static inline struct expression *
98 new_exp_1 (enum operator op, struct expression *right)
100 struct expression *args[1];
103 return new_exp (1, op, args);
106 static struct expression *
107 new_exp_2 (enum operator op, struct expression *left, struct expression *right)
109 struct expression *args[2];
113 return new_exp (2, op, args);
116 static inline struct expression *
117 new_exp_3 (enum operator op, struct expression *bexp,
118 struct expression *tbranch, struct expression *fbranch)
120 struct expression *args[3];
125 return new_exp (3, op, args);
130 /* This declares that all operators have the same associativity and the
131 precedence order as in C. See [Harbison, Steele: C, A Reference Manual].
132 There is no unary minus and no bitwise operators.
133 Operators with the same syntactic behaviour have been merged into a single
134 token, to save space in the array generated by bison. */
138 %left EQUOP2 /* == != */
139 %left CMPOP2 /* < > <= >= */
140 %left ADDOP2 /* + - */
141 %left MULOP2 /* * / % */
144 %token <op> EQUOP2 CMPOP2 ADDOP2 MULOP2
154 ((struct parse_args *) arg)->res = $1;
158 exp: exp '?' exp ':' exp
160 $$ = new_exp_3 (qmop, $1, $3, $5);
164 $$ = new_exp_2 (lor, $1, $3);
168 $$ = new_exp_2 (land, $1, $3);
172 $$ = new_exp_2 ($2, $1, $3);
176 $$ = new_exp_2 ($2, $1, $3);
180 $$ = new_exp_2 ($2, $1, $3);
184 $$ = new_exp_2 ($2, $1, $3);
188 $$ = new_exp_1 (lnot, $2);
192 $$ = new_exp_0 (var);
196 if (($$ = new_exp_0 (num)) != NULL)
209 FREE_EXPRESSION (struct expression *exp)
214 /* Handle the recursive case. */
218 FREE_EXPRESSION (exp->val.args[2]);
221 FREE_EXPRESSION (exp->val.args[1]);
224 FREE_EXPRESSION (exp->val.args[0]);
235 yylex (YYSTYPE *lval, const char **pexp)
237 const char *exp = *pexp;
248 if (exp[0] != ' ' && exp[0] != '\t')
257 case '0': case '1': case '2': case '3': case '4':
258 case '5': case '6': case '7': case '8': case '9':
260 unsigned long int n = result - '0';
261 while (exp[0] >= '0' && exp[0] <= '9')
287 lval->op = not_equal;
294 if (exp[0] == result)
304 lval->op = less_or_equal;
307 lval->op = less_than;
315 lval->op = greater_or_equal;
318 lval->op = greater_than;
352 /* Nothing, just return the character. */
358 /* Be safe and let the user call this function again. */
378 yyerror (const char *str)
380 /* Do nothing. We don't print error messages here. */