| 1 | %{ |
| 2 | /* Expression parsing for plural form selection. |
| 3 | Copyright (C) 2000, 2001 Free Software Foundation, Inc. |
| 4 | Written by Ulrich Drepper <drepper@cygnus.com>, 2000. |
| 5 | |
| 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) |
| 9 | any later version. |
| 10 | |
| 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. |
| 15 | |
| 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., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, |
| 19 | USA. */ |
| 20 | |
| 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__ |
| 26 | #pragma alloca |
| 27 | #endif |
| 28 | |
| 29 | #ifdef HAVE_CONFIG_H |
| 30 | # include <config.h> |
| 31 | #endif |
| 32 | |
| 33 | #include <stddef.h> |
| 34 | #include <stdlib.h> |
| 35 | #include "plural-exp.h" |
| 36 | |
| 37 | /* The main function generated by the parser is called __gettextparse, |
| 38 | but we want it to be called PLURAL_PARSE. */ |
| 39 | #ifndef _LIBC |
| 40 | # define __gettextparse PLURAL_PARSE |
| 41 | #endif |
| 42 | |
| 43 | #define YYLEX_PARAM &((struct parse_args *) arg)->cp |
| 44 | #define YYPARSE_PARAM arg |
| 45 | %} |
| 46 | %pure_parser |
| 47 | %expect 7 |
| 48 | |
| 49 | %union { |
| 50 | unsigned long int num; |
| 51 | enum operator op; |
| 52 | struct expression *exp; |
| 53 | } |
| 54 | |
| 55 | %{ |
| 56 | /* Prototypes for local functions. */ |
| 57 | static struct expression *new_exp PARAMS ((int nargs, enum operator op, |
| 58 | struct expression * const *args)); |
| 59 | static inline struct expression *new_exp_0 PARAMS ((enum operator op)); |
| 60 | static inline struct expression *new_exp_1 PARAMS ((enum operator op, |
| 61 | struct expression *right)); |
| 62 | static struct expression *new_exp_2 PARAMS ((enum operator op, |
| 63 | struct expression *left, |
| 64 | struct expression *right)); |
| 65 | static inline struct expression *new_exp_3 PARAMS ((enum operator op, |
| 66 | struct expression *bexp, |
| 67 | struct expression *tbranch, |
| 68 | struct expression *fbranch)); |
| 69 | static int yylex PARAMS ((YYSTYPE *lval, const char **pexp)); |
| 70 | static void yyerror PARAMS ((const char *str)); |
| 71 | |
| 72 | /* Allocation of expressions. */ |
| 73 | |
| 74 | static struct expression * |
| 75 | new_exp (nargs, op, args) |
| 76 | int nargs; |
| 77 | enum operator op; |
| 78 | struct expression * const *args; |
| 79 | { |
| 80 | int i; |
| 81 | struct expression *newp; |
| 82 | |
| 83 | /* If any of the argument could not be malloc'ed, just return NULL. */ |
| 84 | for (i = nargs - 1; i >= 0; i--) |
| 85 | if (args[i] == NULL) |
| 86 | goto fail; |
| 87 | |
| 88 | /* Allocate a new expression. */ |
| 89 | newp = (struct expression *) malloc (sizeof (*newp)); |
| 90 | if (newp != NULL) |
| 91 | { |
| 92 | newp->nargs = nargs; |
| 93 | newp->operation = op; |
| 94 | for (i = nargs - 1; i >= 0; i--) |
| 95 | newp->val.args[i] = args[i]; |
| 96 | return newp; |
| 97 | } |
| 98 | |
| 99 | fail: |
| 100 | for (i = nargs - 1; i >= 0; i--) |
| 101 | FREE_EXPRESSION (args[i]); |
| 102 | |
| 103 | return NULL; |
| 104 | } |
| 105 | |
| 106 | static inline struct expression * |
| 107 | new_exp_0 (op) |
| 108 | enum operator op; |
| 109 | { |
| 110 | return new_exp (0, op, NULL); |
| 111 | } |
| 112 | |
| 113 | static inline struct expression * |
| 114 | new_exp_1 (op, right) |
| 115 | enum operator op; |
| 116 | struct expression *right; |
| 117 | { |
| 118 | struct expression *args[1]; |
| 119 | |
| 120 | args[0] = right; |
| 121 | return new_exp (1, op, args); |
| 122 | } |
| 123 | |
| 124 | static struct expression * |
| 125 | new_exp_2 (op, left, right) |
| 126 | enum operator op; |
| 127 | struct expression *left; |
| 128 | struct expression *right; |
| 129 | { |
| 130 | struct expression *args[2]; |
| 131 | |
| 132 | args[0] = left; |
| 133 | args[1] = right; |
| 134 | return new_exp (2, op, args); |
| 135 | } |
| 136 | |
| 137 | static inline struct expression * |
| 138 | new_exp_3 (op, bexp, tbranch, fbranch) |
| 139 | enum operator op; |
| 140 | struct expression *bexp; |
| 141 | struct expression *tbranch; |
| 142 | struct expression *fbranch; |
| 143 | { |
| 144 | struct expression *args[3]; |
| 145 | |
| 146 | args[0] = bexp; |
| 147 | args[1] = tbranch; |
| 148 | args[2] = fbranch; |
| 149 | return new_exp (3, op, args); |
| 150 | } |
| 151 | |
| 152 | %} |
| 153 | |
| 154 | /* This declares that all operators have the same associativity and the |
| 155 | precedence order as in C. See [Harbison, Steele: C, A Reference Manual]. |
| 156 | There is no unary minus and no bitwise operators. |
| 157 | Operators with the same syntactic behaviour have been merged into a single |
| 158 | token, to save space in the array generated by bison. */ |
| 159 | %right '?' /* ? */ |
| 160 | %left '|' /* || */ |
| 161 | %left '&' /* && */ |
| 162 | %left EQUOP2 /* == != */ |
| 163 | %left CMPOP2 /* < > <= >= */ |
| 164 | %left ADDOP2 /* + - */ |
| 165 | %left MULOP2 /* * / % */ |
| 166 | %right '!' /* ! */ |
| 167 | |
| 168 | %token <op> EQUOP2 CMPOP2 ADDOP2 MULOP2 |
| 169 | %token <num> NUMBER |
| 170 | %type <exp> exp |
| 171 | |
| 172 | %% |
| 173 | |
| 174 | start: exp |
| 175 | { |
| 176 | if ($1 == NULL) |
| 177 | YYABORT; |
| 178 | ((struct parse_args *) arg)->res = $1; |
| 179 | } |
| 180 | ; |
| 181 | |
| 182 | exp: exp '?' exp ':' exp |
| 183 | { |
| 184 | $$ = new_exp_3 (qmop, $1, $3, $5); |
| 185 | } |
| 186 | | exp '|' exp |
| 187 | { |
| 188 | $$ = new_exp_2 (lor, $1, $3); |
| 189 | } |
| 190 | | exp '&' exp |
| 191 | { |
| 192 | $$ = new_exp_2 (land, $1, $3); |
| 193 | } |
| 194 | | exp EQUOP2 exp |
| 195 | { |
| 196 | $$ = new_exp_2 ($2, $1, $3); |
| 197 | } |
| 198 | | exp CMPOP2 exp |
| 199 | { |
| 200 | $$ = new_exp_2 ($2, $1, $3); |
| 201 | } |
| 202 | | exp ADDOP2 exp |
| 203 | { |
| 204 | $$ = new_exp_2 ($2, $1, $3); |
| 205 | } |
| 206 | | exp MULOP2 exp |
| 207 | { |
| 208 | $$ = new_exp_2 ($2, $1, $3); |
| 209 | } |
| 210 | | '!' exp |
| 211 | { |
| 212 | $$ = new_exp_1 (lnot, $2); |
| 213 | } |
| 214 | | 'n' |
| 215 | { |
| 216 | $$ = new_exp_0 (var); |
| 217 | } |
| 218 | | NUMBER |
| 219 | { |
| 220 | if (($$ = new_exp_0 (num)) != NULL) |
| 221 | $$->val.num = $1; |
| 222 | } |
| 223 | | '(' exp ')' |
| 224 | { |
| 225 | $$ = $2; |
| 226 | } |
| 227 | ; |
| 228 | |
| 229 | %% |
| 230 | |
| 231 | void |
| 232 | internal_function |
| 233 | FREE_EXPRESSION (exp) |
| 234 | struct expression *exp; |
| 235 | { |
| 236 | if (exp == NULL) |
| 237 | return; |
| 238 | |
| 239 | /* Handle the recursive case. */ |
| 240 | switch (exp->nargs) |
| 241 | { |
| 242 | case 3: |
| 243 | FREE_EXPRESSION (exp->val.args[2]); |
| 244 | /* FALLTHROUGH */ |
| 245 | case 2: |
| 246 | FREE_EXPRESSION (exp->val.args[1]); |
| 247 | /* FALLTHROUGH */ |
| 248 | case 1: |
| 249 | FREE_EXPRESSION (exp->val.args[0]); |
| 250 | /* FALLTHROUGH */ |
| 251 | default: |
| 252 | break; |
| 253 | } |
| 254 | |
| 255 | free (exp); |
| 256 | } |
| 257 | |
| 258 | |
| 259 | static int |
| 260 | yylex (lval, pexp) |
| 261 | YYSTYPE *lval; |
| 262 | const char **pexp; |
| 263 | { |
| 264 | const char *exp = *pexp; |
| 265 | int result; |
| 266 | |
| 267 | while (1) |
| 268 | { |
| 269 | if (exp[0] == '\0') |
| 270 | { |
| 271 | *pexp = exp; |
| 272 | return YYEOF; |
| 273 | } |
| 274 | |
| 275 | if (exp[0] != ' ' && exp[0] != '\t') |
| 276 | break; |
| 277 | |
| 278 | ++exp; |
| 279 | } |
| 280 | |
| 281 | result = *exp++; |
| 282 | switch (result) |
| 283 | { |
| 284 | case '0': case '1': case '2': case '3': case '4': |
| 285 | case '5': case '6': case '7': case '8': case '9': |
| 286 | { |
| 287 | unsigned long int n = result - '0'; |
| 288 | while (exp[0] >= '0' && exp[0] <= '9') |
| 289 | { |
| 290 | n *= 10; |
| 291 | n += exp[0] - '0'; |
| 292 | ++exp; |
| 293 | } |
| 294 | lval->num = n; |
| 295 | result = NUMBER; |
| 296 | } |
| 297 | break; |
| 298 | |
| 299 | case '=': |
| 300 | if (exp[0] == '=') |
| 301 | { |
| 302 | ++exp; |
| 303 | lval->op = equal; |
| 304 | result = EQUOP2; |
| 305 | } |
| 306 | else |
| 307 | result = YYERRCODE; |
| 308 | break; |
| 309 | |
| 310 | case '!': |
| 311 | if (exp[0] == '=') |
| 312 | { |
| 313 | ++exp; |
| 314 | lval->op = not_equal; |
| 315 | result = EQUOP2; |
| 316 | } |
| 317 | break; |
| 318 | |
| 319 | case '&': |
| 320 | case '|': |
| 321 | if (exp[0] == result) |
| 322 | ++exp; |
| 323 | else |
| 324 | result = YYERRCODE; |
| 325 | break; |
| 326 | |
| 327 | case '<': |
| 328 | if (exp[0] == '=') |
| 329 | { |
| 330 | ++exp; |
| 331 | lval->op = less_or_equal; |
| 332 | } |
| 333 | else |
| 334 | lval->op = less_than; |
| 335 | result = CMPOP2; |
| 336 | break; |
| 337 | |
| 338 | case '>': |
| 339 | if (exp[0] == '=') |
| 340 | { |
| 341 | ++exp; |
| 342 | lval->op = greater_or_equal; |
| 343 | } |
| 344 | else |
| 345 | lval->op = greater_than; |
| 346 | result = CMPOP2; |
| 347 | break; |
| 348 | |
| 349 | case '*': |
| 350 | lval->op = mult; |
| 351 | result = MULOP2; |
| 352 | break; |
| 353 | |
| 354 | case '/': |
| 355 | lval->op = divide; |
| 356 | result = MULOP2; |
| 357 | break; |
| 358 | |
| 359 | case '%': |
| 360 | lval->op = module; |
| 361 | result = MULOP2; |
| 362 | break; |
| 363 | |
| 364 | case '+': |
| 365 | lval->op = plus; |
| 366 | result = ADDOP2; |
| 367 | break; |
| 368 | |
| 369 | case '-': |
| 370 | lval->op = minus; |
| 371 | result = ADDOP2; |
| 372 | break; |
| 373 | |
| 374 | case 'n': |
| 375 | case '?': |
| 376 | case ':': |
| 377 | case '(': |
| 378 | case ')': |
| 379 | /* Nothing, just return the character. */ |
| 380 | break; |
| 381 | |
| 382 | case ';': |
| 383 | case '\n': |
| 384 | case '\0': |
| 385 | /* Be safe and let the user call this function again. */ |
| 386 | --exp; |
| 387 | result = YYEOF; |
| 388 | break; |
| 389 | |
| 390 | default: |
| 391 | result = YYERRCODE; |
| 392 | #if YYDEBUG != 0 |
| 393 | --exp; |
| 394 | #endif |
| 395 | break; |
| 396 | } |
| 397 | |
| 398 | *pexp = exp; |
| 399 | |
| 400 | return result; |
| 401 | } |
| 402 | |
| 403 | |
| 404 | static void |
| 405 | yyerror (str) |
| 406 | const char *str; |
| 407 | { |
| 408 | /* Do nothing. We don't print error messages here. */ |
| 409 | } |