2 /* Expression parsing for plural form selection.
3 Copyright (C) 2000-2022 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
7 it under the terms of the GNU Lesser General Public License as published by
8 the Free Software Foundation; either version 2.1 of the License, or
9 (at your option) any later version.
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
14 GNU Lesser General Public License for more details.
16 You should have received a copy of the GNU Lesser General Public License
17 along with this program. If not, see <https://www.gnu.org/licenses/>. */
19 /* For bison < 2.0, the bison generated parser uses alloca. AIX 3 forces us
20 to put this declaration at the beginning of the file. The declaration in
21 bison's skeleton file comes too late. This must come before <config.h>
22 because <config.h> may include arbitrary system headers.
23 This can go away once the AM_INTL_SUBDIR macro requires bison >= 2.0. */
24 #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 /* Later we provide those prototypes. Without these macros, bison may
44 generate its own prototypes with possible conflicts. */
45 #define YYLEX_IS_DECLARED
46 #define YYERROR_IS_DECLARED
49 %parse-param {struct parse_args *arg}
50 %lex-param {struct parse_args *arg}
55 unsigned long int num;
56 enum expression_operator op;
57 struct expression *exp;
61 /* Prototypes for local functions. */
62 static int yylex (YYSTYPE *lval, struct parse_args *arg);
63 static void yyerror (struct parse_args *arg, const char *str);
65 /* Allocation of expressions. */
67 static struct expression *
68 new_exp (int nargs, enum expression_operator op,
69 struct expression * const *args)
72 struct expression *newp;
74 /* If any of the argument could not be malloc'ed, just return NULL. */
75 for (i = nargs - 1; i >= 0; i--)
79 /* Allocate a new expression. */
80 newp = (struct expression *) malloc (sizeof (*newp));
85 for (i = nargs - 1; i >= 0; i--)
86 newp->val.args[i] = args[i];
91 for (i = nargs - 1; i >= 0; i--)
92 FREE_EXPRESSION (args[i]);
97 static inline struct expression *
98 new_exp_0 (enum expression_operator op)
100 return new_exp (0, op, NULL);
103 static inline struct expression *
104 new_exp_1 (enum expression_operator op, struct expression *right)
106 struct expression *args[1];
109 return new_exp (1, op, args);
112 static struct expression *
113 new_exp_2 (enum expression_operator op, struct expression *left,
114 struct expression *right)
116 struct expression *args[2];
120 return new_exp (2, op, args);
123 static inline struct expression *
124 new_exp_3 (enum expression_operator op, struct expression *bexp,
125 struct expression *tbranch, struct expression *fbranch)
127 struct expression *args[3];
132 return new_exp (3, op, args);
137 /* This declares that all operators have the same associativity and the
138 precedence order as in C. See [Harbison, Steele: C, A Reference Manual].
139 There is no unary minus and no bitwise operators.
140 Operators with the same syntactic behaviour have been merged into a single
141 token, to save space in the array generated by bison. */
145 %left EQUOP2 /* == != */
146 %left CMPOP2 /* < > <= >= */
147 %left ADDOP2 /* + - */
148 %left MULOP2 /* * / % */
151 %token <op> EQUOP2 CMPOP2 ADDOP2 MULOP2
165 exp: exp '?' exp ':' exp
167 $$ = new_exp_3 (qmop, $1, $3, $5);
171 $$ = new_exp_2 (lor, $1, $3);
175 $$ = new_exp_2 (land, $1, $3);
179 $$ = new_exp_2 ($2, $1, $3);
183 $$ = new_exp_2 ($2, $1, $3);
187 $$ = new_exp_2 ($2, $1, $3);
191 $$ = new_exp_2 ($2, $1, $3);
195 $$ = new_exp_1 (lnot, $2);
199 $$ = new_exp_0 (var);
203 if (($$ = new_exp_0 (num)) != NULL)
215 FREE_EXPRESSION (struct expression *exp)
220 /* Handle the recursive case. */
224 FREE_EXPRESSION (exp->val.args[2]);
227 FREE_EXPRESSION (exp->val.args[1]);
230 FREE_EXPRESSION (exp->val.args[0]);
241 yylex (YYSTYPE *lval, struct parse_args *arg)
243 const char *exp = arg->cp;
254 if (exp[0] != ' ' && exp[0] != '\t')
263 case '0': case '1': case '2': case '3': case '4':
264 case '5': case '6': case '7': case '8': case '9':
266 unsigned long int n = result - '0';
267 while (exp[0] >= '0' && exp[0] <= '9')
293 lval->op = not_equal;
300 if (exp[0] == result)
310 lval->op = less_or_equal;
313 lval->op = less_than;
321 lval->op = greater_or_equal;
324 lval->op = greater_than;
358 /* Nothing, just return the character. */
364 /* Be safe and let the user call this function again. */
384 yyerror (struct parse_args *arg, const char *str)
386 /* Do nothing. We don't print error messages here. */