src/common/filter/filter-parser.y

   1 %{
   2 /*
   3  * filter-parser.y
   4  *
   5  * LTTng filter expression parser
   6  *
   7  * Copyright 2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   8  *
   9  * SPDX-License-Identifier: LGPL-2.1-only
  10  *
  11  * Grammar inspired from http://www.quut.com/c/ANSI-C-grammar-y.html
  12  */
  13
  14 #include <stdio.h>
  15 #include <unistd.h>
  16 #include <string.h>
  17 #include <stdlib.h>
  18 #include <assert.h>
  19 #include <errno.h>
  20 #include <inttypes.h>
  21 #include "filter-ast.h"
  22 #include "filter-parser.h"
  23 #include "filter-bytecode.h"
  24 #include "memstream.h"
  25
  26 #include <common/macros.h>
  27
  28 #define WIDTH_u64_SCANF_IS_A_BROKEN_API "20"
  29 #define WIDTH_o64_SCANF_IS_A_BROKEN_API "22"
  30 #define WIDTH_x64_SCANF_IS_A_BROKEN_API "17"
  31 #define WIDTH_lg_SCANF_IS_A_BROKEN_API  "4096"  /* Hugely optimistic approximation */
  32
  33 #ifdef DEBUG
  34 static const int print_xml = 1;
  35 #define dbg_printf(fmt, args...)        \
  36         printf("[debug filter_parser] " fmt, ## args)
  37 #else
  38 static const int print_xml = 0;
  39 #define dbg_printf(fmt, args...)                                \
  40 do {                                                            \
  41         /* do nothing but check printf format */                \
  42         if (0)                                                  \
  43                 printf("[debug filter_parser] " fmt, ## args);  \
  44 } while (0)
  45 #endif
  46
  47 LTTNG_HIDDEN
  48 int yydebug;
  49 LTTNG_HIDDEN
  50 int filter_parser_debug = 0;
  51
  52 LTTNG_HIDDEN
  53 int yyparse(struct filter_parser_ctx *parser_ctx, yyscan_t scanner);
  54 LTTNG_HIDDEN
  55 int yylex(union YYSTYPE *yyval, yyscan_t scanner);
  56 LTTNG_HIDDEN
  57 int yylex_init_extra(struct filter_parser_ctx *parser_ctx, yyscan_t * ptr_yy_globals);
  58 LTTNG_HIDDEN
  59 int yylex_destroy(yyscan_t yyparser_ctx);
  60 LTTNG_HIDDEN
  61 void yyrestart(FILE * in_str, yyscan_t parser_ctx);
  62
  63 struct gc_string {
  64         struct cds_list_head gc;
  65         size_t alloclen;
  66         char s[];
  67 };
  68
  69 static const char *node_type_to_str[] = {
  70         [ NODE_UNKNOWN ] = "NODE_UNKNOWN",
  71         [ NODE_ROOT ] = "NODE_ROOT",
  72         [ NODE_EXPRESSION ] = "NODE_EXPRESSION",
  73         [ NODE_OP ] = "NODE_OP",
  74         [ NODE_UNARY_OP ] = "NODE_UNARY_OP",
  75 };
  76
  77 LTTNG_HIDDEN
  78 const char *node_type(struct filter_node *node)
  79 {
  80         if (node->type < NR_NODE_TYPES)
  81                 return node_type_to_str[node->type];
  82         else
  83                 return NULL;
  84 }
  85
  86 static struct gc_string *gc_string_alloc(struct filter_parser_ctx *parser_ctx,
  87                                          size_t len)
  88 {
  89         struct gc_string *gstr;
  90         size_t alloclen;
  91
  92         /* TODO: could be faster with find first bit or glib Gstring */
  93         /* sizeof long to account for malloc header (int or long ?) */
  94         for (alloclen = 8; alloclen < sizeof(long) + sizeof(*gstr) + len;
  95              alloclen *= 2);
  96
  97         gstr = zmalloc(alloclen);
  98         if (!gstr) {
  99                 goto end;
 100         }
 101         cds_list_add(&gstr->gc, &parser_ctx->allocated_strings);
 102         gstr->alloclen = alloclen;
 103 end:
 104         return gstr;
 105 }
 106
 107 /*
 108  * note: never use gc_string_append on a string that has external references.
 109  * gsrc will be garbage collected immediately, and gstr might be.
 110  * Should only be used to append characters to a string literal or constant.
 111  */
 112 static
 113 struct gc_string *gc_string_append(struct filter_parser_ctx *parser_ctx,
 114                                    struct gc_string *gstr,
 115                                    struct gc_string *gsrc)
 116 {
 117         size_t newlen = strlen(gsrc->s) + strlen(gstr->s) + 1;
 118         size_t alloclen;
 119
 120         /* TODO: could be faster with find first bit or glib Gstring */
 121         /* sizeof long to account for malloc header (int or long ?) */
 122         for (alloclen = 8; alloclen < sizeof(long) + sizeof(*gstr) + newlen;
 123              alloclen *= 2);
 124
 125         if (alloclen > gstr->alloclen) {
 126                 struct gc_string *newgstr;
 127
 128                 newgstr = gc_string_alloc(parser_ctx, newlen);
 129                 strcpy(newgstr->s, gstr->s);
 130                 strcat(newgstr->s, gsrc->s);
 131                 cds_list_del(&gstr->gc);
 132                 free(gstr);
 133                 gstr = newgstr;
 134         } else {
 135                 strcat(gstr->s, gsrc->s);
 136         }
 137         cds_list_del(&gsrc->gc);
 138         free(gsrc);
 139         return gstr;
 140 }
 141
 142 LTTNG_HIDDEN
 143 void setstring(struct filter_parser_ctx *parser_ctx, YYSTYPE *lvalp, const char *src);
 144 LTTNG_HIDDEN
 145 void setstring(struct filter_parser_ctx *parser_ctx, YYSTYPE *lvalp, const char *src)
 146 {
 147         lvalp->gs = gc_string_alloc(parser_ctx, strlen(src) + 1);
 148         strcpy(lvalp->gs->s, src);
 149 }
 150
 151 static struct filter_node *make_node(struct filter_parser_ctx *scanner,
 152                                   enum node_type type)
 153 {
 154         struct filter_ast *ast = filter_parser_get_ast(scanner);
 155         struct filter_node *node;
 156
 157         node = zmalloc(sizeof(*node));
 158         if (!node)
 159                 return NULL;
 160         memset(node, 0, sizeof(*node));
 161         node->type = type;
 162         cds_list_add(&node->gc, &ast->allocated_nodes);
 163
 164         switch (type) {
 165         case NODE_ROOT:
 166                 fprintf(stderr, "[error] %s: trying to create root node\n", __func__);
 167                 break;
 168
 169         case NODE_EXPRESSION:
 170                 break;
 171         case NODE_OP:
 172                 break;
 173         case NODE_UNARY_OP:
 174                 break;
 175
 176         case NODE_UNKNOWN:
 177         default:
 178                 fprintf(stderr, "[error] %s: unknown node type %d\n", __func__,
 179                         (int) type);
 180                 break;
 181         }
 182
 183         return node;
 184 }
 185
 186 static struct filter_node *make_op_node(struct filter_parser_ctx *scanner,
 187                         enum op_type type,
 188                         struct filter_node *lchild,
 189                         struct filter_node *rchild)
 190 {
 191         struct filter_ast *ast = filter_parser_get_ast(scanner);
 192         struct filter_node *node;
 193
 194         node = zmalloc(sizeof(*node));
 195         if (!node)
 196                 return NULL;
 197         memset(node, 0, sizeof(*node));
 198         node->type = NODE_OP;
 199         cds_list_add(&node->gc, &ast->allocated_nodes);
 200         node->u.op.type = type;
 201         node->u.op.lchild = lchild;
 202         node->u.op.rchild = rchild;
 203         return node;
 204 }
 205
 206 LTTNG_HIDDEN
 207 void yyerror(struct filter_parser_ctx *parser_ctx, yyscan_t scanner, const char *str);
 208 LTTNG_HIDDEN
 209 void yyerror(struct filter_parser_ctx *parser_ctx, yyscan_t scanner, const char *str)
 210 {
 211         fprintf(stderr, "error %s\n", str);
 212 }
 213
 214 LTTNG_HIDDEN
 215 int yywrap(void);
 216 LTTNG_HIDDEN
 217 int yywrap(void)
 218 {
 219         return 1;
 220 }
 221
 222 #define parse_error(parser_ctx, str)                            \
 223 do {                                                            \
 224         yyerror(parser_ctx, parser_ctx->scanner, YY_("parse error: " str "\n"));        \
 225         YYERROR;                                                \
 226 } while (0)
 227
 228 static void free_strings(struct cds_list_head *list)
 229 {
 230         struct gc_string *gstr, *tmp;
 231
 232         cds_list_for_each_entry_safe(gstr, tmp, list, gc)
 233                 free(gstr);
 234 }
 235
 236 static struct filter_ast *filter_ast_alloc(void)
 237 {
 238         struct filter_ast *ast;
 239
 240         ast = zmalloc(sizeof(*ast));
 241         if (!ast)
 242                 return NULL;
 243         memset(ast, 0, sizeof(*ast));
 244         CDS_INIT_LIST_HEAD(&ast->allocated_nodes);
 245         ast->root.type = NODE_ROOT;
 246         return ast;
 247 }
 248
 249 static void filter_ast_free(struct filter_ast *ast)
 250 {
 251         struct filter_node *node, *tmp;
 252
 253         cds_list_for_each_entry_safe(node, tmp, &ast->allocated_nodes, gc)
 254                 free(node);
 255         free(ast);
 256 }
 257
 258 LTTNG_HIDDEN
 259 int filter_parser_ctx_append_ast(struct filter_parser_ctx *parser_ctx)
 260 {
 261         return yyparse(parser_ctx, parser_ctx->scanner);
 262 }
 263
 264 LTTNG_HIDDEN
 265 struct filter_parser_ctx *filter_parser_ctx_alloc(FILE *input)
 266 {
 267         struct filter_parser_ctx *parser_ctx;
 268         int ret;
 269
 270         yydebug = filter_parser_debug;
 271
 272         parser_ctx = zmalloc(sizeof(*parser_ctx));
 273         if (!parser_ctx)
 274                 return NULL;
 275         memset(parser_ctx, 0, sizeof(*parser_ctx));
 276
 277         ret = yylex_init_extra(parser_ctx, &parser_ctx->scanner);
 278         if (ret) {
 279                 fprintf(stderr, "yylex_init error\n");
 280                 goto cleanup_parser_ctx;
 281         }
 282         /* Start processing new stream */
 283         yyrestart(input, parser_ctx->scanner);
 284
 285         parser_ctx->ast = filter_ast_alloc();
 286         if (!parser_ctx->ast)
 287                 goto cleanup_lexer;
 288         CDS_INIT_LIST_HEAD(&parser_ctx->allocated_strings);
 289
 290         if (yydebug)
 291                 fprintf(stdout, "parser_ctx input is a%s.\n",
 292                         isatty(fileno(input)) ? "n interactive tty" :
 293                                                 " noninteractive file");
 294
 295         return parser_ctx;
 296
 297 cleanup_lexer:
 298         ret = yylex_destroy(parser_ctx->scanner);
 299         if (!ret)
 300                 fprintf(stderr, "yylex_destroy error\n");
 301 cleanup_parser_ctx:
 302         free(parser_ctx);
 303         return NULL;
 304 }
 305
 306 LTTNG_HIDDEN
 307 void filter_parser_ctx_free(struct filter_parser_ctx *parser_ctx)
 308 {
 309         int ret;
 310
 311         free_strings(&parser_ctx->allocated_strings);
 312         filter_ast_free(parser_ctx->ast);
 313         ret = yylex_destroy(parser_ctx->scanner);
 314         if (ret)
 315                 fprintf(stderr, "yylex_destroy error\n");
 316         free(parser_ctx);
 317 }
 318
 319 LTTNG_HIDDEN
 320 int filter_parser_ctx_create_from_filter_expression(
 321                 const char *filter_expression, struct filter_parser_ctx **ctxp)
 322 {
 323         int ret;
 324         struct filter_parser_ctx *ctx = NULL;
 325         FILE *fmem = NULL;
 326
 327         assert(filter_expression);
 328         assert(ctxp);
 329
 330         /*
 331          * Casting const to non-const, as the underlying function will use it in
 332          * read-only mode.
 333          */
 334         fmem = lttng_fmemopen((void *) filter_expression,
 335                         strlen(filter_expression), "r");
 336         if (!fmem) {
 337                 fprintf(stderr, "Error opening memory as stream\n");
 338                 ret = -LTTNG_ERR_FILTER_NOMEM;
 339                 goto error;
 340         }
 341         ctx = filter_parser_ctx_alloc(fmem);
 342         if (!ctx) {
 343                 fprintf(stderr, "Error allocating parser\n");
 344                 ret = -LTTNG_ERR_FILTER_NOMEM;
 345                 goto filter_alloc_error;
 346         }
 347         ret = filter_parser_ctx_append_ast(ctx);
 348         if (ret) {
 349                 fprintf(stderr, "Parse error\n");
 350                 ret = -LTTNG_ERR_FILTER_INVAL;
 351                 goto parse_error;
 352         }
 353         if (print_xml) {
 354                 ret = filter_visitor_print_xml(ctx, stdout, 0);
 355                 if (ret) {
 356                         fflush(stdout);
 357                         fprintf(stderr, "XML print error\n");
 358                         ret = -LTTNG_ERR_FILTER_INVAL;
 359                         goto parse_error;
 360                 }
 361         }
 362
 363         dbg_printf("Generating IR... ");
 364         fflush(stdout);
 365         ret = filter_visitor_ir_generate(ctx);
 366         if (ret) {
 367                 fprintf(stderr, "Generate IR error\n");
 368                 ret = -LTTNG_ERR_FILTER_INVAL;
 369                 goto parse_error;
 370         }
 371         dbg_printf("done\n");
 372
 373         dbg_printf("Validating IR... ");
 374         fflush(stdout);
 375         ret = filter_visitor_ir_check_binary_op_nesting(ctx);
 376         if (ret) {
 377                 ret = -LTTNG_ERR_FILTER_INVAL;
 378                 goto parse_error;
 379         }
 380
 381         /* Normalize globbing patterns in the expression. */
 382         ret = filter_visitor_ir_normalize_glob_patterns(ctx);
 383         if (ret) {
 384                 ret = -LTTNG_ERR_FILTER_INVAL;
 385                 goto parse_error;
 386         }
 387
 388         /* Validate strings used as literals in the expression. */
 389         ret = filter_visitor_ir_validate_string(ctx);
 390         if (ret) {
 391                 ret = -LTTNG_ERR_FILTER_INVAL;
 392                 goto parse_error;
 393         }
 394
 395         /* Validate globbing patterns in the expression. */
 396         ret = filter_visitor_ir_validate_globbing(ctx);
 397         if (ret) {
 398                 ret = -LTTNG_ERR_FILTER_INVAL;
 399                 goto parse_error;
 400         }
 401
 402         dbg_printf("done\n");
 403
 404         dbg_printf("Generating bytecode... ");
 405         fflush(stdout);
 406         ret = filter_visitor_bytecode_generate(ctx);
 407         if (ret) {
 408                 fprintf(stderr, "Generate bytecode error\n");
 409                 ret = -LTTNG_ERR_FILTER_INVAL;
 410                 goto parse_error;
 411         }
 412         dbg_printf("done\n");
 413         dbg_printf("Size of bytecode generated: %u bytes.\n",
 414                         bytecode_get_len(&ctx->bytecode->b));
 415
 416         /* No need to keep the memory stream. */
 417         if (fclose(fmem) != 0) {
 418                 fprintf(stderr, "fclose (%d) \n", errno);
 419                 ret = -LTTNG_ERR_FILTER_INVAL;
 420         }
 421
 422         *ctxp = ctx;
 423         return 0;
 424
 425 parse_error:
 426         filter_ir_free(ctx);
 427         filter_parser_ctx_free(ctx);
 428 filter_alloc_error:
 429         if (fclose(fmem) != 0) {
 430                 fprintf(stderr, "fclose (%d) \n", errno);
 431         }
 432 error:
 433         return ret;
 434 }
 435
 436 %}
 437
 438 %define api.pure
 439         /* %locations */
 440 %parse-param {struct filter_parser_ctx *parser_ctx}
 441 %parse-param {yyscan_t scanner}
 442 %lex-param {yyscan_t scanner}
 443 %start translation_unit
 444 %token CHARACTER_CONSTANT_START SQUOTE STRING_LITERAL_START DQUOTE
 445 %token ESCSEQ CHAR_STRING_TOKEN
 446 %token DECIMAL_CONSTANT OCTAL_CONSTANT HEXADECIMAL_CONSTANT FLOAT_CONSTANT
 447 %token LSBRAC RSBRAC LPAREN RPAREN LBRAC RBRAC RARROW
 448 %token STAR PLUS MINUS
 449 %token MOD_OP DIV_OP RIGHT_OP LEFT_OP
 450 %token EQ_OP NE_OP LE_OP GE_OP LT_OP GT_OP AND_OP OR_OP NOT_OP
 451 %token ASSIGN COLON SEMICOLON DOTDOTDOT DOT EQUAL COMMA
 452 %token XOR_BIN AND_BIN OR_BIN NOT_BIN
 453
 454 %token <gs> IDENTIFIER GLOBAL_IDENTIFIER
 455 %token ERROR
 456 %union
 457 {
 458         long long ll;
 459         char c;
 460         struct gc_string *gs;
 461         struct filter_node *n;
 462 }
 463
 464 %type <gs> s_char s_char_sequence c_char c_char_sequence
 465
 466 %type <n> primary_expression
 467 %type <n> prefix_expression
 468 %type <n> prefix_expression_rec
 469 %type <n> postfix_expression
 470 %type <n> unary_expression
 471 %type <n> unary_operator
 472 %type <n> multiplicative_expression
 473 %type <n> additive_expression
 474 %type <n> shift_expression
 475 %type <n> relational_expression
 476 %type <n> equality_expression
 477 %type <n> and_expression
 478 %type <n> exclusive_or_expression
 479 %type <n> inclusive_or_expression
 480 %type <n> logical_and_expression
 481 %type <n> logical_or_expression
 482 %type <n> expression
 483 %type <n> identifiers
 484
 485 %%
 486
 487
 488 /* 1.5 Constants */
 489
 490 c_char_sequence:
 491                 c_char
 492                 {       $$ = $1;                                        }
 493         |       c_char_sequence c_char
 494                 {       $$ = gc_string_append(parser_ctx, $1, $2);              }
 495         ;
 496
 497 c_char:
 498                 CHAR_STRING_TOKEN
 499                 {       $$ = yylval.gs;                                 }
 500         |       ESCSEQ
 501                 {
 502                         parse_error(parser_ctx, "escape sequences not supported yet");
 503                 }
 504         ;
 505
 506 /* 1.6 String literals */
 507
 508 s_char_sequence:
 509                 s_char
 510                 {       $$ = $1;                                        }
 511         |       s_char_sequence s_char
 512                 {       $$ = gc_string_append(parser_ctx, $1, $2);              }
 513         ;
 514
 515 s_char:
 516                 CHAR_STRING_TOKEN
 517                 {       $$ = yylval.gs;                                 }
 518         |       ESCSEQ
 519                 {
 520                         parse_error(parser_ctx, "escape sequences not supported yet");
 521                 }
 522         ;
 523
 524 primary_expression:
 525                 DECIMAL_CONSTANT
 526                 {
 527                         $$ = make_node(parser_ctx, NODE_EXPRESSION);
 528                         $$->u.expression.type = AST_EXP_CONSTANT;
 529                         if (sscanf(yylval.gs->s, "%" WIDTH_u64_SCANF_IS_A_BROKEN_API SCNu64,
 530                                         &$$->u.expression.u.constant) != 1) {
 531                                 parse_error(parser_ctx, "cannot scanf decimal constant");
 532                         }
 533                 }
 534         |       OCTAL_CONSTANT
 535                 {
 536                         $$ = make_node(parser_ctx, NODE_EXPRESSION);
 537                         $$->u.expression.type = AST_EXP_CONSTANT;
 538                         if (!strcmp(yylval.gs->s, "0")) {
 539                                 $$->u.expression.u.constant = 0;
 540                         } else if (sscanf(yylval.gs->s, "0%" WIDTH_o64_SCANF_IS_A_BROKEN_API SCNo64,
 541                                         &$$->u.expression.u.constant) != 1) {
 542                                 parse_error(parser_ctx, "cannot scanf octal constant");
 543                         }
 544                 }
 545         |       HEXADECIMAL_CONSTANT
 546                 {
 547                         $$ = make_node(parser_ctx, NODE_EXPRESSION);
 548                         $$->u.expression.type = AST_EXP_CONSTANT;
 549                         if (sscanf(yylval.gs->s, "0x%" WIDTH_x64_SCANF_IS_A_BROKEN_API SCNx64,
 550                                         &$$->u.expression.u.constant) != 1) {
 551                                 parse_error(parser_ctx, "cannot scanf hexadecimal constant");
 552                         }
 553                 }
 554         |       FLOAT_CONSTANT
 555                 {
 556                         $$ = make_node(parser_ctx, NODE_EXPRESSION);
 557                         $$->u.expression.type = AST_EXP_FLOAT_CONSTANT;
 558                         if (sscanf(yylval.gs->s, "%" WIDTH_lg_SCANF_IS_A_BROKEN_API "lg",
 559                                         &$$->u.expression.u.float_constant) != 1) {
 560                                 parse_error(parser_ctx, "cannot scanf float constant");
 561                         }
 562                 }
 563         |       STRING_LITERAL_START DQUOTE
 564                 {
 565                         $$ = make_node(parser_ctx, NODE_EXPRESSION);
 566                         $$->u.expression.type = AST_EXP_STRING;
 567                         $$->u.expression.u.string = "";
 568                 }
 569         |       STRING_LITERAL_START s_char_sequence DQUOTE
 570                 {
 571                         $$ = make_node(parser_ctx, NODE_EXPRESSION);
 572                         $$->u.expression.type = AST_EXP_STRING;
 573                         $$->u.expression.u.string = $2->s;
 574                 }
 575         |       CHARACTER_CONSTANT_START c_char_sequence SQUOTE
 576                 {
 577                         $$ = make_node(parser_ctx, NODE_EXPRESSION);
 578                         $$->u.expression.type = AST_EXP_STRING;
 579                         $$->u.expression.u.string = $2->s;
 580                 }
 581         |       LPAREN expression RPAREN
 582                 {
 583                         $$ = make_node(parser_ctx, NODE_EXPRESSION);
 584                         $$->u.expression.type = AST_EXP_NESTED;
 585                         $$->u.expression.u.child = $2;
 586                 }
 587         ;
 588
 589 identifiers
 590         :       IDENTIFIER
 591                 {
 592                         $$ = make_node(parser_ctx, NODE_EXPRESSION);
 593                         $$->u.expression.type = AST_EXP_IDENTIFIER;
 594                         $$->u.expression.u.identifier = yylval.gs->s;
 595                 }
 596         |       GLOBAL_IDENTIFIER
 597                 {
 598                         $$ = make_node(parser_ctx, NODE_EXPRESSION);
 599                         $$->u.expression.type = AST_EXP_GLOBAL_IDENTIFIER;
 600                         $$->u.expression.u.identifier = yylval.gs->s;
 601                 }
 602         ;
 603
 604 prefix_expression_rec
 605         : LSBRAC unary_expression RSBRAC
 606                 {
 607                         $$ = $2;
 608                 }
 609         | LSBRAC unary_expression RSBRAC prefix_expression_rec
 610                 {
 611                         $$ = $2;
 612                         $$->u.expression.pre_op = AST_LINK_BRACKET;
 613                         $$->u.expression.prev = $4;
 614                 }
 615         ;
 616
 617 prefix_expression
 618         : identifiers
 619                 {
 620                         $$ = $1;
 621                 }
 622         | identifiers prefix_expression_rec
 623                 {
 624                         $$ = $1;
 625                         $$->u.expression.pre_op = AST_LINK_BRACKET;
 626                         $$->u.expression.next_bracket = $2;
 627                 }
 628         ;
 629
 630 postfix_expression
 631         : prefix_expression
 632                 {
 633                         $$ = $1;
 634                 }
 635         | postfix_expression DOT prefix_expression
 636                 {
 637                         $$ = $3;
 638                         $$->u.expression.post_op = AST_LINK_DOT;
 639                         $$->u.expression.prev = $1;
 640                 }
 641         | postfix_expression RARROW prefix_expression
 642                 {
 643                         $$ = $3;
 644                         $$->u.expression.post_op = AST_LINK_RARROW;
 645                         $$->u.expression.prev = $1;
 646                 }
 647         ;
 648
 649 unary_expression
 650         : postfix_expression
 651                 {       $$ = $1;                                        }
 652         | primary_expression
 653                 {       $$ = $1;                                        }
 654         | unary_operator unary_expression
 655                 {
 656                         $$ = $1;
 657                         $$->u.unary_op.child = $2;
 658                 }
 659         ;
 660
 661 unary_operator
 662         : PLUS
 663                 {
 664                         $$ = make_node(parser_ctx, NODE_UNARY_OP);
 665                         $$->u.unary_op.type = AST_UNARY_PLUS;
 666                 }
 667         | MINUS
 668                 {
 669                         $$ = make_node(parser_ctx, NODE_UNARY_OP);
 670                         $$->u.unary_op.type = AST_UNARY_MINUS;
 671                 }
 672         | NOT_OP
 673                 {
 674                         $$ = make_node(parser_ctx, NODE_UNARY_OP);
 675                         $$->u.unary_op.type = AST_UNARY_NOT;
 676                 }
 677         | NOT_BIN
 678                 {
 679                         $$ = make_node(parser_ctx, NODE_UNARY_OP);
 680                         $$->u.unary_op.type = AST_UNARY_BIT_NOT;
 681                 }
 682         ;
 683
 684 multiplicative_expression
 685         : unary_expression
 686                 {       $$ = $1;                                        }
 687         | multiplicative_expression STAR unary_expression
 688                 {
 689                         $$ = make_op_node(parser_ctx, AST_OP_MUL, $1, $3);
 690                 }
 691         | multiplicative_expression DIV_OP unary_expression
 692                 {
 693                         $$ = make_op_node(parser_ctx, AST_OP_DIV, $1, $3);
 694                 }
 695         | multiplicative_expression MOD_OP unary_expression
 696                 {
 697                         $$ = make_op_node(parser_ctx, AST_OP_MOD, $1, $3);
 698                 }
 699         ;
 700
 701 additive_expression
 702         : multiplicative_expression
 703                 {       $$ = $1;                                        }
 704         | additive_expression PLUS multiplicative_expression
 705                 {
 706                         $$ = make_op_node(parser_ctx, AST_OP_PLUS, $1, $3);
 707                 }
 708         | additive_expression MINUS multiplicative_expression
 709                 {
 710                         $$ = make_op_node(parser_ctx, AST_OP_MINUS, $1, $3);
 711                 }
 712         ;
 713
 714 shift_expression
 715         : additive_expression
 716                 {       $$ = $1;                                        }
 717         | shift_expression LEFT_OP additive_expression
 718                 {
 719                         $$ = make_op_node(parser_ctx, AST_OP_BIT_LSHIFT, $1, $3);
 720                 }
 721         | shift_expression RIGHT_OP additive_expression
 722                 {
 723                         $$ = make_op_node(parser_ctx, AST_OP_BIT_RSHIFT, $1, $3);
 724                 }
 725         ;
 726
 727 and_expression
 728         : shift_expression
 729                 {       $$ = $1;                                        }
 730         | and_expression AND_BIN shift_expression
 731                 {
 732                         $$ = make_op_node(parser_ctx, AST_OP_BIT_AND, $1, $3);
 733                 }
 734         ;
 735
 736 exclusive_or_expression
 737         : and_expression
 738                 {       $$ = $1;                                        }
 739         | exclusive_or_expression XOR_BIN and_expression
 740                 {
 741                         $$ = make_op_node(parser_ctx, AST_OP_BIT_XOR, $1, $3);
 742                 }
 743         ;
 744
 745 inclusive_or_expression
 746         : exclusive_or_expression
 747                 {       $$ = $1;                                        }
 748         | inclusive_or_expression OR_BIN exclusive_or_expression
 749                 {
 750                         $$ = make_op_node(parser_ctx, AST_OP_BIT_OR, $1, $3);
 751                 }
 752         ;
 753
 754 relational_expression
 755         : inclusive_or_expression
 756                 {       $$ = $1;                                        }
 757         | relational_expression LT_OP inclusive_or_expression
 758                 {
 759                         $$ = make_op_node(parser_ctx, AST_OP_LT, $1, $3);
 760                 }
 761         | relational_expression GT_OP inclusive_or_expression
 762                 {
 763                         $$ = make_op_node(parser_ctx, AST_OP_GT, $1, $3);
 764                 }
 765         | relational_expression LE_OP inclusive_or_expression
 766                 {
 767                         $$ = make_op_node(parser_ctx, AST_OP_LE, $1, $3);
 768                 }
 769         | relational_expression GE_OP inclusive_or_expression
 770                 {
 771                         $$ = make_op_node(parser_ctx, AST_OP_GE, $1, $3);
 772                 }
 773         ;
 774
 775 equality_expression
 776         : relational_expression
 777                 {       $$ = $1;                                        }
 778         | equality_expression EQ_OP relational_expression
 779                 {
 780                         $$ = make_op_node(parser_ctx, AST_OP_EQ, $1, $3);
 781                 }
 782         | equality_expression NE_OP relational_expression
 783                 {
 784                         $$ = make_op_node(parser_ctx, AST_OP_NE, $1, $3);
 785                 }
 786         ;
 787
 788 logical_and_expression
 789         : equality_expression
 790                 {       $$ = $1;                                        }
 791         | logical_and_expression AND_OP equality_expression
 792                 {
 793                         $$ = make_op_node(parser_ctx, AST_OP_AND, $1, $3);
 794                 }
 795         ;
 796
 797 logical_or_expression
 798         : logical_and_expression
 799                 {       $$ = $1;                                        }
 800         | logical_or_expression OR_OP logical_and_expression
 801                 {
 802                         $$ = make_op_node(parser_ctx, AST_OP_OR, $1, $3);
 803                 }
 804         ;
 805
 806 expression
 807         : logical_or_expression
 808                 {       $$ = $1;                                        }
 809         ;
 810
 811 translation_unit
 812         : expression
 813                 {
 814                         parser_ctx->ast->root.u.root.child = $1;
 815                 }
 816         ;