Implement filter expression to bytecode compiler in liblttng-ctl
[lttng-tools.git] / src / lib / lttng-ctl / filter-parser.y
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1%{
2/*
3 * filter-parser.y
4 *
5 * LTTng filter expression parser
6 *
7 * Copyright 2012 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
8 *
9 * This library is free software; you can redistribute it and/or modify it
10 * under the terms of the GNU Lesser General Public License, version 2.1 only,
11 * as published by the Free Software Foundation.
12 *
13 * This library is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
17 *
18 * You should have received a copy of the GNU Lesser General Public License
19 * along with this library; if not, write to the Free Software Foundation,
20 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 *
22 * Grammar inspired from http://www.quut.com/c/ANSI-C-grammar-y.html
23 */
24
25#include <stdio.h>
26#include <unistd.h>
27#include <string.h>
28#include <stdlib.h>
29#include <assert.h>
30#include <errno.h>
31#include <inttypes.h>
32#include "filter-parser.h"
33#include "filter-ast.h"
34
35int yydebug;
36int filter_parser_debug = 0;
37
38int yyparse(struct filter_parser_ctx *parser_ctx);
39int yylex(union YYSTYPE *yyval, struct filter_parser_ctx *parser_ctx);
40int yylex_init_extra(struct filter_parser_ctx *parser_ctx, yyscan_t * ptr_yy_globals);
41int yylex_destroy(yyscan_t yyparser_ctx);
42void yyrestart(FILE * in_str, yyscan_t parser_ctx);
43
44struct gc_string {
45 struct cds_list_head gc;
46 size_t alloclen;
47 char s[];
48};
49
50static const char *node_type_to_str[] = {
51 [ NODE_UNKNOWN ] = "NODE_UNKNOWN",
52 [ NODE_ROOT ] = "NODE_ROOT",
53 [ NODE_EXPRESSION ] = "NODE_EXPRESSION",
54 [ NODE_OP ] = "NODE_OP",
55 [ NODE_UNARY_OP ] = "NODE_UNARY_OP",
56};
57
58const char *node_type(struct filter_node *node)
59{
60 if (node->type < NR_NODE_TYPES)
61 return node_type_to_str[node->type];
62 else
63 return NULL;
64}
65
66static struct gc_string *gc_string_alloc(struct filter_parser_ctx *parser_ctx,
67 size_t len)
68{
69 struct gc_string *gstr;
70 size_t alloclen;
71
72 /* TODO: could be faster with find first bit or glib Gstring */
73 /* sizeof long to account for malloc header (int or long ?) */
74 for (alloclen = 8; alloclen < sizeof(long) + sizeof(*gstr) + len;
75 alloclen *= 2);
76
77 gstr = malloc(alloclen);
78 cds_list_add(&gstr->gc, &parser_ctx->allocated_strings);
79 gstr->alloclen = alloclen;
80 return gstr;
81}
82
83/*
84 * note: never use gc_string_append on a string that has external references.
85 * gsrc will be garbage collected immediately, and gstr might be.
86 * Should only be used to append characters to a string literal or constant.
87 */
88struct gc_string *gc_string_append(struct filter_parser_ctx *parser_ctx,
89 struct gc_string *gstr,
90 struct gc_string *gsrc)
91{
92 size_t newlen = strlen(gsrc->s) + strlen(gstr->s) + 1;
93 size_t alloclen;
94
95 /* TODO: could be faster with find first bit or glib Gstring */
96 /* sizeof long to account for malloc header (int or long ?) */
97 for (alloclen = 8; alloclen < sizeof(long) + sizeof(*gstr) + newlen;
98 alloclen *= 2);
99
100 if (alloclen > gstr->alloclen) {
101 struct gc_string *newgstr;
102
103 newgstr = gc_string_alloc(parser_ctx, newlen);
104 strcpy(newgstr->s, gstr->s);
105 strcat(newgstr->s, gsrc->s);
106 cds_list_del(&gstr->gc);
107 free(gstr);
108 gstr = newgstr;
109 } else {
110 strcat(gstr->s, gsrc->s);
111 }
112 cds_list_del(&gsrc->gc);
113 free(gsrc);
114 return gstr;
115}
116
117void setstring(struct filter_parser_ctx *parser_ctx, YYSTYPE *lvalp, const char *src)
118{
119 lvalp->gs = gc_string_alloc(parser_ctx, strlen(src) + 1);
120 strcpy(lvalp->gs->s, src);
121}
122
123static struct filter_node *make_node(struct filter_parser_ctx *scanner,
124 enum node_type type)
125{
126 struct filter_ast *ast = filter_parser_get_ast(scanner);
127 struct filter_node *node;
128
129 node = malloc(sizeof(*node));
130 if (!node)
131 return NULL;
132 memset(node, 0, sizeof(*node));
133 node->type = type;
134 cds_list_add(&node->gc, &ast->allocated_nodes);
135
136 switch (type) {
137 case NODE_ROOT:
138 fprintf(stderr, "[error] %s: trying to create root node\n", __func__);
139 break;
140
141 case NODE_EXPRESSION:
142 break;
143 case NODE_OP:
144 break;
145 case NODE_UNARY_OP:
146 break;
147
148 case NODE_UNKNOWN:
149 default:
150 fprintf(stderr, "[error] %s: unknown node type %d\n", __func__,
151 (int) type);
152 break;
153 }
154
155 return node;
156}
157
158static struct filter_node *make_op_node(struct filter_parser_ctx *scanner,
159 enum op_type type,
160 struct filter_node *lchild,
161 struct filter_node *rchild)
162{
163 struct filter_ast *ast = filter_parser_get_ast(scanner);
164 struct filter_node *node;
165
166 node = malloc(sizeof(*node));
167 if (!node)
168 return NULL;
169 memset(node, 0, sizeof(*node));
170 node->type = NODE_OP;
171 cds_list_add(&node->gc, &ast->allocated_nodes);
172 node->u.op.type = type;
173 node->u.op.lchild = lchild;
174 node->u.op.rchild = rchild;
175 return node;
176}
177
178void yyerror(struct filter_parser_ctx *parser_ctx, const char *str)
179{
180 fprintf(stderr, "error %s\n", str);
181}
182
183int yywrap(void)
184{
185 return 1;
186}
187
188#define parse_error(parser_ctx, str) \
189do { \
190 yyerror(parser_ctx, YY_("parse error: " str "\n")); \
191 YYERROR; \
192} while (0)
193
194static void free_strings(struct cds_list_head *list)
195{
196 struct gc_string *gstr, *tmp;
197
198 cds_list_for_each_entry_safe(gstr, tmp, list, gc)
199 free(gstr);
200}
201
202static struct filter_ast *filter_ast_alloc(void)
203{
204 struct filter_ast *ast;
205
206 ast = malloc(sizeof(*ast));
207 if (!ast)
208 return NULL;
209 memset(ast, 0, sizeof(*ast));
210 CDS_INIT_LIST_HEAD(&ast->allocated_nodes);
211 ast->root.type = NODE_ROOT;
212 return ast;
213}
214
215static void filter_ast_free(struct filter_ast *ast)
216{
217 struct filter_node *node, *tmp;
218
219 cds_list_for_each_entry_safe(node, tmp, &ast->allocated_nodes, gc)
220 free(node);
221}
222
223int filter_parser_ctx_append_ast(struct filter_parser_ctx *parser_ctx)
224{
225 return yyparse(parser_ctx);
226}
227
228struct filter_parser_ctx *filter_parser_ctx_alloc(FILE *input)
229{
230 struct filter_parser_ctx *parser_ctx;
231 int ret;
232
233 yydebug = filter_parser_debug;
234
235 parser_ctx = malloc(sizeof(*parser_ctx));
236 if (!parser_ctx)
237 return NULL;
238 memset(parser_ctx, 0, sizeof(*parser_ctx));
239
240 ret = yylex_init_extra(parser_ctx, &parser_ctx->scanner);
241 if (ret) {
242 fprintf(stderr, "yylex_init error\n");
243 goto cleanup_parser_ctx;
244 }
245 /* Start processing new stream */
246 yyrestart(input, parser_ctx->scanner);
247
248 parser_ctx->ast = filter_ast_alloc();
249 if (!parser_ctx->ast)
250 goto cleanup_lexer;
251 CDS_INIT_LIST_HEAD(&parser_ctx->allocated_strings);
252
253 if (yydebug)
254 fprintf(stdout, "parser_ctx input is a%s.\n",
255 isatty(fileno(input)) ? "n interactive tty" :
256 " noninteractive file");
257
258 return parser_ctx;
259
260cleanup_lexer:
261 ret = yylex_destroy(parser_ctx->scanner);
262 if (!ret)
263 fprintf(stderr, "yylex_destroy error\n");
264cleanup_parser_ctx:
265 free(parser_ctx);
266 return NULL;
267}
268
269void filter_parser_ctx_free(struct filter_parser_ctx *parser_ctx)
270{
271 int ret;
272
273 free_strings(&parser_ctx->allocated_strings);
274 filter_ast_free(parser_ctx->ast);
275 ret = yylex_destroy(parser_ctx->scanner);
276 if (ret)
277 fprintf(stderr, "yylex_destroy error\n");
278 free(parser_ctx);
279}
280
281%}
282
283%define api.pure
284 /* %locations */
285%parse-param {struct filter_parser_ctx *parser_ctx}
286%lex-param {struct filter_parser_ctx *parser_ctx}
287%start translation_unit
288%token CHARACTER_CONSTANT_START SQUOTE STRING_LITERAL_START DQUOTE
289%token ESCSEQ CHAR_STRING_TOKEN
290%token DECIMAL_CONSTANT OCTAL_CONSTANT HEXADECIMAL_CONSTANT
291%token LSBRAC RSBRAC LPAREN RPAREN LBRAC RBRAC RARROW
292%token STAR PLUS MINUS
293%token MOD_OP DIV_OP RIGHT_OP LEFT_OP
294%token EQ_OP NE_OP LE_OP GE_OP LT_OP GT_OP AND_OP OR_OP NOT_OP
295%token ASSIGN COLON SEMICOLON DOTDOTDOT DOT EQUAL COMMA
296%token XOR_BIN AND_BIN OR_BIN NOT_BIN
297
298%token <gs> IDENTIFIER
299%token ERROR
300%union
301{
302 long long ll;
303 char c;
304 struct gc_string *gs;
305 struct filter_node *n;
306}
307
308%type <gs> s_char s_char_sequence c_char c_char_sequence
309
310%type <n> primary_expression
311%type <n> postfix_expression
312%type <n> unary_expression
313%type <n> unary_operator
314%type <n> multiplicative_expression
315%type <n> additive_expression
316%type <n> shift_expression
317%type <n> relational_expression
318%type <n> equality_expression
319%type <n> and_expression
320%type <n> exclusive_or_expression
321%type <n> inclusive_or_expression
322%type <n> logical_and_expression
323%type <n> logical_or_expression
324%type <n> expression
325
326%%
327
328
329/* 1.5 Constants */
330
331c_char_sequence:
332 c_char
333 { $$ = $1; }
334 | c_char_sequence c_char
335 { $$ = gc_string_append(parser_ctx, $1, $2); }
336 ;
337
338c_char:
339 CHAR_STRING_TOKEN
340 { $$ = yylval.gs; }
341 | ESCSEQ
342 {
343 parse_error(parser_ctx, "escape sequences not supported yet");
344 }
345 ;
346
347/* 1.6 String literals */
348
349s_char_sequence:
350 s_char
351 { $$ = $1; }
352 | s_char_sequence s_char
353 { $$ = gc_string_append(parser_ctx, $1, $2); }
354 ;
355
356s_char:
357 CHAR_STRING_TOKEN
358 { $$ = yylval.gs; }
359 | ESCSEQ
360 {
361 parse_error(parser_ctx, "escape sequences not supported yet");
362 }
363 ;
364
365primary_expression
366 : IDENTIFIER
367 {
368 $$ = make_node(parser_ctx, NODE_EXPRESSION);
369 $$->u.expression.type = AST_EXP_IDENTIFIER;
370 $$->u.expression.u.identifier = yylval.gs->s;
371 }
372 | DECIMAL_CONSTANT
373 {
374 $$ = make_node(parser_ctx, NODE_EXPRESSION);
375 $$->u.expression.type = AST_EXP_CONSTANT;
376 sscanf(yylval.gs->s, "%" PRIu64,
377 &$$->u.expression.u.constant);
378 }
379 | OCTAL_CONSTANT
380 {
381 $$ = make_node(parser_ctx, NODE_EXPRESSION);
382 $$->u.expression.type = AST_EXP_CONSTANT;
383 sscanf(yylval.gs->s, "0%" PRIo64,
384 &$$->u.expression.u.constant);
385 }
386 | HEXADECIMAL_CONSTANT
387 {
388 $$ = make_node(parser_ctx, NODE_EXPRESSION);
389 $$->u.expression.type = AST_EXP_CONSTANT;
390 sscanf(yylval.gs->s, "0x%" PRIx64,
391 &$$->u.expression.u.constant);
392 }
393 | STRING_LITERAL_START DQUOTE
394 {
395 $$ = make_node(parser_ctx, NODE_EXPRESSION);
396 $$->u.expression.type = AST_EXP_STRING;
397 $$->u.expression.u.string = "";
398 }
399 | STRING_LITERAL_START s_char_sequence DQUOTE
400 {
401 $$ = make_node(parser_ctx, NODE_EXPRESSION);
402 $$->u.expression.type = AST_EXP_STRING;
403 $$->u.expression.u.string = $2->s;
404 }
405 | CHARACTER_CONSTANT_START c_char_sequence SQUOTE
406 {
407 $$ = make_node(parser_ctx, NODE_EXPRESSION);
408 $$->u.expression.type = AST_EXP_STRING;
409 $$->u.expression.u.string = $2->s;
410 }
411 | LPAREN expression RPAREN
412 {
413 $$ = make_node(parser_ctx, NODE_EXPRESSION);
414 $$->u.expression.type = AST_EXP_NESTED;
415 $$->u.expression.u.child = $2;
416 }
417 ;
418
419postfix_expression
420 : primary_expression
421 { $$ = $1; }
422 | postfix_expression DOT IDENTIFIER
423 {
424 $$ = make_node(parser_ctx, NODE_EXPRESSION);
425 $$->u.expression.type = AST_EXP_IDENTIFIER;
426 $$->u.expression.post_op = AST_LINK_DOT;
427 $$->u.expression.u.identifier = $3->s;
428 $$->u.expression.prev = $1;
429 }
430 | postfix_expression RARROW IDENTIFIER
431 {
432 $$ = make_node(parser_ctx, NODE_EXPRESSION);
433 $$->u.expression.type = AST_EXP_IDENTIFIER;
434 $$->u.expression.post_op = AST_LINK_RARROW;
435 $$->u.expression.u.identifier = $3->s;
436 $$->u.expression.prev = $1;
437 }
438 ;
439
440unary_expression
441 : postfix_expression
442 { $$ = $1; }
443 | unary_operator unary_expression
444 {
445 $$ = $1;
446 $$->u.unary_op.child = $2;
447 }
448 ;
449
450unary_operator
451 : PLUS
452 {
453 $$ = make_node(parser_ctx, NODE_UNARY_OP);
454 $$->u.unary_op.type = AST_UNARY_PLUS;
455 }
456 | MINUS
457 {
458 $$ = make_node(parser_ctx, NODE_UNARY_OP);
459 $$->u.unary_op.type = AST_UNARY_MINUS;
460 }
461 | NOT_OP
462 {
463 $$ = make_node(parser_ctx, NODE_UNARY_OP);
464 $$->u.unary_op.type = AST_UNARY_NOT;
465 }
466 ;
467
468multiplicative_expression
469 : unary_expression
470 { $$ = $1; }
471 | multiplicative_expression STAR unary_expression
472 {
473 $$ = make_op_node(parser_ctx, AST_OP_MUL, $1, $3);
474 }
475 | multiplicative_expression DIV_OP unary_expression
476 {
477 $$ = make_op_node(parser_ctx, AST_OP_DIV, $1, $3);
478 }
479 | multiplicative_expression MOD_OP unary_expression
480 {
481 $$ = make_op_node(parser_ctx, AST_OP_MOD, $1, $3);
482 }
483 ;
484
485additive_expression
486 : multiplicative_expression
487 { $$ = $1; }
488 | additive_expression PLUS multiplicative_expression
489 {
490 $$ = make_op_node(parser_ctx, AST_OP_PLUS, $1, $3);
491 }
492 | additive_expression MINUS multiplicative_expression
493 {
494 $$ = make_op_node(parser_ctx, AST_OP_MINUS, $1, $3);
495 }
496 ;
497
498shift_expression
499 : additive_expression
500 { $$ = $1; }
501 | shift_expression LEFT_OP additive_expression
502 {
503 $$ = make_op_node(parser_ctx, AST_OP_LSHIFT, $1, $3);
504 }
505 | shift_expression RIGHT_OP additive_expression
506 {
507 $$ = make_op_node(parser_ctx, AST_OP_RSHIFT, $1, $3);
508 }
509 ;
510
511relational_expression
512 : shift_expression
513 { $$ = $1; }
514 | relational_expression LT_OP shift_expression
515 {
516 $$ = make_op_node(parser_ctx, AST_OP_LT, $1, $3);
517 }
518 | relational_expression GT_OP shift_expression
519 {
520 $$ = make_op_node(parser_ctx, AST_OP_GT, $1, $3);
521 }
522 | relational_expression LE_OP shift_expression
523 {
524 $$ = make_op_node(parser_ctx, AST_OP_LE, $1, $3);
525 }
526 | relational_expression GE_OP shift_expression
527 {
528 $$ = make_op_node(parser_ctx, AST_OP_GE, $1, $3);
529 }
530 ;
531
532equality_expression
533 : relational_expression
534 { $$ = $1; }
535 | equality_expression EQ_OP relational_expression
536 {
537 $$ = make_op_node(parser_ctx, AST_OP_EQ, $1, $3);
538 }
539 | equality_expression NE_OP relational_expression
540 {
541 $$ = make_op_node(parser_ctx, AST_OP_NE, $1, $3);
542 }
543 ;
544
545and_expression
546 : equality_expression
547 { $$ = $1; }
548 | and_expression AND_BIN equality_expression
549 {
550 $$ = make_op_node(parser_ctx, AST_OP_BIN_AND, $1, $3);
551 }
552 ;
553
554exclusive_or_expression
555 : and_expression
556 { $$ = $1; }
557 | exclusive_or_expression XOR_BIN and_expression
558 {
559 $$ = make_op_node(parser_ctx, AST_OP_BIN_XOR, $1, $3);
560 }
561 ;
562
563inclusive_or_expression
564 : exclusive_or_expression
565 { $$ = $1; }
566 | inclusive_or_expression OR_BIN exclusive_or_expression
567 {
568 $$ = make_op_node(parser_ctx, AST_OP_BIN_OR, $1, $3);
569 }
570 ;
571
572logical_and_expression
573 : inclusive_or_expression
574 { $$ = $1; }
575 | logical_and_expression AND_OP inclusive_or_expression
576 {
577 $$ = make_op_node(parser_ctx, AST_OP_AND, $1, $3);
578 }
579 ;
580
581logical_or_expression
582 : logical_and_expression
583 { $$ = $1; }
584 | logical_or_expression OR_OP logical_and_expression
585 {
586 $$ = make_op_node(parser_ctx, AST_OP_OR, $1, $3);
587 }
588 ;
589
590expression
591 : logical_or_expression
592 { $$ = $1; }
593 ;
594
595translation_unit
596 : expression
597 {
598 parser_ctx->ast->root.u.root.child = $1;
599 }
600 ;
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