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+%{
+/* Expression parsing for plural form selection.
+ Copyright (C) 2000, 2001 Free Software Foundation, Inc.
+ Written by Ulrich Drepper <[email protected]>, 2000.
+
+ This program is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Library General Public License as published
+ by the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Library General Public License for more details.
+
+ You should have received a copy of the GNU Library General Public
+ License along with this program; if not, write to the Free Software
+ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
+ USA. */
+
+/* The bison generated parser uses alloca. AIX 3 forces us to put this
+ declaration at the beginning of the file. The declaration in bison's
+ skeleton file comes too late. This must come before <config.h>
+ because <config.h> may include arbitrary system headers. */
+#if defined _AIX && !defined __GNUC__
+ #pragma alloca
+#endif
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include <stddef.h>
+#include <stdlib.h>
+#include "plural-exp.h"
+
+/* The main function generated by the parser is called __gettextparse,
+ but we want it to be called PLURAL_PARSE. */
+#ifndef _LIBC
+# define __gettextparse PLURAL_PARSE
+#endif
+
+#define YYLEX_PARAM &((struct parse_args *) arg)->cp
+#define YYPARSE_PARAM arg
+%}
+%pure_parser
+%expect 7
+
+%union {
+ unsigned long int num;
+ enum operator op;
+ struct expression *exp;
+}
+
+%{
+/* Prototypes for local functions. */
+static struct expression *new_exp PARAMS ((int nargs, enum operator op,
+ struct expression * const *args));
+static inline struct expression *new_exp_0 PARAMS ((enum operator op));
+static inline struct expression *new_exp_1 PARAMS ((enum operator op,
+ struct expression *right));
+static struct expression *new_exp_2 PARAMS ((enum operator op,
+ struct expression *left,
+ struct expression *right));
+static inline struct expression *new_exp_3 PARAMS ((enum operator op,
+ struct expression *bexp,
+ struct expression *tbranch,
+ struct expression *fbranch));
+static int yylex PARAMS ((YYSTYPE *lval, const char **pexp));
+static void yyerror PARAMS ((const char *str));
+
+/* Allocation of expressions. */
+
+static struct expression *
+new_exp (nargs, op, args)
+ int nargs;
+ enum operator op;
+ struct expression * const *args;
+{
+ int i;
+ struct expression *newp;
+
+ /* If any of the argument could not be malloc'ed, just return NULL. */
+ for (i = nargs - 1; i >= 0; i--)
+ if (args[i] == NULL)
+ goto fail;
+
+ /* Allocate a new expression. */
+ newp = (struct expression *) malloc (sizeof (*newp));
+ if (newp != NULL)
+ {
+ newp->nargs = nargs;
+ newp->operation = op;
+ for (i = nargs - 1; i >= 0; i--)
+ newp->val.args[i] = args[i];
+ return newp;
+ }
+
+ fail:
+ for (i = nargs - 1; i >= 0; i--)
+ FREE_EXPRESSION (args[i]);
+
+ return NULL;
+}
+
+static inline struct expression *
+new_exp_0 (op)
+ enum operator op;
+{
+ return new_exp (0, op, NULL);
+}
+
+static inline struct expression *
+new_exp_1 (op, right)
+ enum operator op;
+ struct expression *right;
+{
+ struct expression *args[1];
+
+ args[0] = right;
+ return new_exp (1, op, args);
+}
+
+static struct expression *
+new_exp_2 (op, left, right)
+ enum operator op;
+ struct expression *left;
+ struct expression *right;
+{
+ struct expression *args[2];
+
+ args[0] = left;
+ args[1] = right;
+ return new_exp (2, op, args);
+}
+
+static inline struct expression *
+new_exp_3 (op, bexp, tbranch, fbranch)
+ enum operator op;
+ struct expression *bexp;
+ struct expression *tbranch;
+ struct expression *fbranch;
+{
+ struct expression *args[3];
+
+ args[0] = bexp;
+ args[1] = tbranch;
+ args[2] = fbranch;
+ return new_exp (3, op, args);
+}
+
+%}
+
+/* This declares that all operators have the same associativity and the
+ precedence order as in C. See [Harbison, Steele: C, A Reference Manual].
+ There is no unary minus and no bitwise operators.
+ Operators with the same syntactic behaviour have been merged into a single
+ token, to save space in the array generated by bison. */
+%right '?' /* ? */
+%left '|' /* || */
+%left '&' /* && */
+%left EQUOP2 /* == != */
+%left CMPOP2 /* < > <= >= */
+%left ADDOP2 /* + - */
+%left MULOP2 /* * / % */
+%right '!' /* ! */
+
+%token <op> EQUOP2 CMPOP2 ADDOP2 MULOP2
+%token <num> NUMBER
+%type <exp> exp
+
+%%
+
+start: exp
+ {
+ if ($1 == NULL)
+ YYABORT;
+ ((struct parse_args *) arg)->res = $1;
+ }
+ ;
+
+exp: exp '?' exp ':' exp
+ {
+ $$ = new_exp_3 (qmop, $1, $3, $5);
+ }
+ | exp '|' exp
+ {
+ $$ = new_exp_2 (lor, $1, $3);
+ }
+ | exp '&' exp
+ {
+ $$ = new_exp_2 (land, $1, $3);
+ }
+ | exp EQUOP2 exp
+ {
+ $$ = new_exp_2 ($2, $1, $3);
+ }
+ | exp CMPOP2 exp
+ {
+ $$ = new_exp_2 ($2, $1, $3);
+ }
+ | exp ADDOP2 exp
+ {
+ $$ = new_exp_2 ($2, $1, $3);
+ }
+ | exp MULOP2 exp
+ {
+ $$ = new_exp_2 ($2, $1, $3);
+ }
+ | '!' exp
+ {
+ $$ = new_exp_1 (lnot, $2);
+ }
+ | 'n'
+ {
+ $$ = new_exp_0 (var);
+ }
+ | NUMBER
+ {
+ if (($$ = new_exp_0 (num)) != NULL)
+ $$->val.num = $1;
+ }
+ | '(' exp ')'
+ {
+ $$ = $2;
+ }
+ ;
+
+%%
+
+void
+internal_function
+FREE_EXPRESSION (exp)
+ struct expression *exp;
+{
+ if (exp == NULL)
+ return;
+
+ /* Handle the recursive case. */
+ switch (exp->nargs)
+ {
+ case 3:
+ FREE_EXPRESSION (exp->val.args[2]);
+ /* FALLTHROUGH */
+ case 2:
+ FREE_EXPRESSION (exp->val.args[1]);
+ /* FALLTHROUGH */
+ case 1:
+ FREE_EXPRESSION (exp->val.args[0]);
+ /* FALLTHROUGH */
+ default:
+ break;
+ }
+
+ free (exp);
+}
+
+
+static int
+yylex (lval, pexp)
+ YYSTYPE *lval;
+ const char **pexp;
+{
+ const char *exp = *pexp;
+ int result;
+
+ while (1)
+ {
+ if (exp[0] == '\0')
+ {
+ *pexp = exp;
+ return YYEOF;
+ }
+
+ if (exp[0] != ' ' && exp[0] != '\t')
+ break;
+
+ ++exp;
+ }
+
+ result = *exp++;
+ switch (result)
+ {
+ case '0': case '1': case '2': case '3': case '4':
+ case '5': case '6': case '7': case '8': case '9':
+ {
+ unsigned long int n = result - '0';
+ while (exp[0] >= '0' && exp[0] <= '9')
+ {
+ n *= 10;
+ n += exp[0] - '0';
+ ++exp;
+ }
+ lval->num = n;
+ result = NUMBER;
+ }
+ break;
+
+ case '=':
+ if (exp[0] == '=')
+ {
+ ++exp;
+ lval->op = equal;
+ result = EQUOP2;
+ }
+ else
+ result = YYERRCODE;
+ break;
+
+ case '!':
+ if (exp[0] == '=')
+ {
+ ++exp;
+ lval->op = not_equal;
+ result = EQUOP2;
+ }
+ break;
+
+ case '&':
+ case '|':
+ if (exp[0] == result)
+ ++exp;
+ else
+ result = YYERRCODE;
+ break;
+
+ case '<':
+ if (exp[0] == '=')
+ {
+ ++exp;
+ lval->op = less_or_equal;
+ }
+ else
+ lval->op = less_than;
+ result = CMPOP2;
+ break;
+
+ case '>':
+ if (exp[0] == '=')
+ {
+ ++exp;
+ lval->op = greater_or_equal;
+ }
+ else
+ lval->op = greater_than;
+ result = CMPOP2;
+ break;
+
+ case '*':
+ lval->op = mult;
+ result = MULOP2;
+ break;
+
+ case '/':
+ lval->op = divide;
+ result = MULOP2;
+ break;
+
+ case '%':
+ lval->op = module;
+ result = MULOP2;
+ break;
+
+ case '+':
+ lval->op = plus;
+ result = ADDOP2;
+ break;
+
+ case '-':
+ lval->op = minus;
+ result = ADDOP2;
+ break;
+
+ case 'n':
+ case '?':
+ case ':':
+ case '(':
+ case ')':
+ /* Nothing, just return the character. */
+ break;
+
+ case ';':
+ case '\n':
+ case '\0':
+ /* Be safe and let the user call this function again. */
+ --exp;
+ result = YYEOF;
+ break;
+
+ default:
+ result = YYERRCODE;
+#if YYDEBUG != 0
+ --exp;
+#endif
+ break;
+ }
+
+ *pexp = exp;
+
+ return result;
+}
+
+
+static void
+yyerror (str)
+ const char *str;
+{
+ /* Do nothing. We don't print error messages here. */
+}