2 /* Expression parsing for plural form selection.
3 Copyright (C) 2000-2015 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 <http://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
44 %parse-param {struct parse_args *arg}
45 %lex-param {struct parse_args *arg}
50 unsigned long int num;
51 enum expression_operator op;
52 struct expression *exp;
56 /* Prototypes for local functions. */
57 static int yylex (YYSTYPE *lval, struct parse_args *arg);
58 static void yyerror (struct parse_args *arg, const char *str);
60 /* Allocation of expressions. */
62 static struct expression *
63 new_exp (int nargs, enum expression_operator op,
64 struct expression * const *args)
67 struct expression *newp;
69 /* If any of the argument could not be malloc'ed, just return NULL. */
70 for (i = nargs - 1; i >= 0; i--)
74 /* Allocate a new expression. */
75 newp = (struct expression *) malloc (sizeof (*newp));
80 for (i = nargs - 1; i >= 0; i--)
81 newp->val.args[i] = args[i];
86 for (i = nargs - 1; i >= 0; i--)
87 FREE_EXPRESSION (args[i]);
92 static inline struct expression *
93 new_exp_0 (enum expression_operator op)
95 return new_exp (0, op, NULL);
98 static inline struct expression *
99 new_exp_1 (enum expression_operator op, struct expression *right)
101 struct expression *args[1];
104 return new_exp (1, op, args);
107 static struct expression *
108 new_exp_2 (enum expression_operator op, struct expression *left,
109 struct expression *right)
111 struct expression *args[2];
115 return new_exp (2, op, args);
118 static inline struct expression *
119 new_exp_3 (enum expression_operator op, struct expression *bexp,
120 struct expression *tbranch, struct expression *fbranch)
122 struct expression *args[3];
127 return new_exp (3, op, args);
132 /* This declares that all operators have the same associativity and the
133 precedence order as in C. See [Harbison, Steele: C, A Reference Manual].
134 There is no unary minus and no bitwise operators.
135 Operators with the same syntactic behaviour have been merged into a single
136 token, to save space in the array generated by bison. */
140 %left EQUOP2 /* == != */
141 %left CMPOP2 /* < > <= >= */
142 %left ADDOP2 /* + - */
143 %left MULOP2 /* * / % */
146 %token <op> EQUOP2 CMPOP2 ADDOP2 MULOP2
160 exp: exp '?' exp ':' exp
162 $$ = new_exp_3 (qmop, $1, $3, $5);
166 $$ = new_exp_2 (lor, $1, $3);
170 $$ = new_exp_2 (land, $1, $3);
174 $$ = new_exp_2 ($2, $1, $3);
178 $$ = new_exp_2 ($2, $1, $3);
182 $$ = new_exp_2 ($2, $1, $3);
186 $$ = new_exp_2 ($2, $1, $3);
190 $$ = new_exp_1 (lnot, $2);
194 $$ = new_exp_0 (var);
198 if (($$ = new_exp_0 (num)) != NULL)
211 FREE_EXPRESSION (struct expression *exp)
216 /* Handle the recursive case. */
220 FREE_EXPRESSION (exp->val.args[2]);
223 FREE_EXPRESSION (exp->val.args[1]);
226 FREE_EXPRESSION (exp->val.args[0]);
237 yylex (YYSTYPE *lval, struct parse_args *arg)
239 const char *exp = arg->cp;
250 if (exp[0] != ' ' && exp[0] != '\t')
259 case '0': case '1': case '2': case '3': case '4':
260 case '5': case '6': case '7': case '8': case '9':
262 unsigned long int n = result - '0';
263 while (exp[0] >= '0' && exp[0] <= '9')
289 lval->op = not_equal;
296 if (exp[0] == result)
306 lval->op = less_or_equal;
309 lval->op = less_than;
317 lval->op = greater_or_equal;
320 lval->op = greater_than;
354 /* Nothing, just return the character. */
360 /* Be safe and let the user call this function again. */
380 yyerror (struct parse_args *arg, const char *str)
382 /* Do nothing. We don't print error messages here. */