1 /*
2 * SysDB - src/frontend/grammar.y
3 * Copyright (C) 2013 Sebastian 'tokkee' Harl <sh@tokkee.org>
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
17 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
18 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR
19 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
20 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
21 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
22 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
23 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
24 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
25 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
28 %{
30 #include "frontend/connection-private.h"
31 #include "frontend/parser.h"
32 #include "frontend/grammar.h"
34 #include "core/store.h"
35 #include "core/store-private.h"
36 #include "core/time.h"
38 #include "utils/error.h"
39 #include "utils/llist.h"
41 #include <stdio.h>
42 #include <string.h>
44 int
45 sdb_fe_yylex(YYSTYPE *yylval, YYLTYPE *yylloc, sdb_fe_yyscan_t yyscanner);
47 sdb_fe_yyextra_t *
48 sdb_fe_yyget_extra(sdb_fe_yyscan_t scanner);
50 void
51 sdb_fe_yyerror(YYLTYPE *lval, sdb_fe_yyscan_t scanner, const char *msg);
53 /* quick access to the current parse tree */
54 #define pt sdb_fe_yyget_extra(scanner)->parsetree
56 /* quick access to the parser mode */
57 #define parser_mode sdb_fe_yyget_extra(scanner)->mode
59 #define MODE_TO_STRING(m) \
60 (((m) == SDB_PARSE_DEFAULT) ? "statement" \
61 : ((m) == SDB_PARSE_COND) ? "condition" \
62 : ((m) == SDB_PARSE_EXPR) ? "expression" \
63 : "UNKNOWN")
65 %}
67 %pure-parser
68 %lex-param {sdb_fe_yyscan_t scanner}
69 %parse-param {sdb_fe_yyscan_t scanner}
70 %locations
71 %error-verbose
72 %expect 0
73 %name-prefix "sdb_fe_yy"
75 %union {
76 const char *sstr; /* static string */
77 char *str;
79 sdb_data_t data;
80 sdb_time_t datetime;
82 sdb_llist_t *list;
83 sdb_conn_node_t *node;
85 sdb_store_matcher_t *m;
86 sdb_store_expr_t *expr;
87 }
89 %start statements
91 %token SCANNER_ERROR
93 %token AND OR IS NOT MATCHING FILTER
94 %token CMP_EQUAL CMP_NEQUAL CMP_REGEX CMP_NREGEX
95 %token CMP_LT CMP_LE CMP_GE CMP_GT
96 %token CONCAT
98 %token START END
100 /* NULL token */
101 %token NULL_T
103 %token FETCH LIST LOOKUP TIMESERIES
105 %token <str> IDENTIFIER STRING
107 %token <data> INTEGER FLOAT
109 %token <datetime> DATE TIME
111 /* Precedence (lowest first): */
112 %left OR
113 %left AND
114 %right NOT
115 %left CMP_EQUAL CMP_NEQUAL
116 %left CMP_LT CMP_LE CMP_GE CMP_GT
117 %nonassoc CMP_REGEX CMP_NREGEX
118 %left CONCAT
119 %nonassoc IS
120 %left '+' '-'
121 %left '*' '/' '%'
122 %left '[' ']'
123 %left '(' ')'
124 %left '.'
126 %type <list> statements
127 %type <node> statement
128 fetch_statement
129 list_statement
130 lookup_statement
131 timeseries_statement
132 matching_clause
133 filter_clause
134 condition
136 %type <m> matcher
137 compare_matcher
139 %type <expr> expression
141 %type <sstr> cmp
143 %type <data> data
144 interval interval_elem
146 %type <datetime> datetime
147 start_clause end_clause
149 %destructor { free($$); } <str>
150 %destructor { sdb_object_deref(SDB_OBJ($$)); } <node> <m> <expr>
152 %%
154 statements:
155 statements ';' statement
156 {
157 /* only accepted in default parse mode */
158 if (parser_mode != SDB_PARSE_DEFAULT) {
159 char errmsg[1024];
160 snprintf(errmsg, sizeof(errmsg),
161 YY_("syntax error, unexpected statement, "
162 "expecting %s"), MODE_TO_STRING(parser_mode));
163 sdb_fe_yyerror(&yylloc, scanner, errmsg);
164 sdb_object_deref(SDB_OBJ($3));
165 YYABORT;
166 }
168 if ($3) {
169 sdb_llist_append(pt, SDB_OBJ($3));
170 sdb_object_deref(SDB_OBJ($3));
171 }
172 }
173 |
174 statement
175 {
176 /* only accepted in default parse mode */
177 if (parser_mode != SDB_PARSE_DEFAULT) {
178 char errmsg[1024];
179 snprintf(errmsg, sizeof(errmsg),
180 YY_("syntax error, unexpected statement, "
181 "expecting %s"), MODE_TO_STRING(parser_mode));
182 sdb_fe_yyerror(&yylloc, scanner, errmsg);
183 sdb_object_deref(SDB_OBJ($1));
184 YYABORT;
185 }
187 if ($1) {
188 sdb_llist_append(pt, SDB_OBJ($1));
189 sdb_object_deref(SDB_OBJ($1));
190 }
191 }
192 |
193 condition
194 {
195 /* only accepted in condition parse mode */
196 if (! (parser_mode & SDB_PARSE_COND)) {
197 char errmsg[1024];
198 snprintf(errmsg, sizeof(errmsg),
199 YY_("syntax error, unexpected condition, "
200 "expecting %s"), MODE_TO_STRING(parser_mode));
201 sdb_fe_yyerror(&yylloc, scanner, errmsg);
202 sdb_object_deref(SDB_OBJ($1));
203 YYABORT;
204 }
206 if ($1) {
207 sdb_llist_append(pt, SDB_OBJ($1));
208 sdb_object_deref(SDB_OBJ($1));
209 }
210 }
211 |
212 expression
213 {
214 /* only accepted in expression parse mode */
215 if (! (parser_mode & SDB_PARSE_EXPR)) {
216 char errmsg[1024];
217 snprintf(errmsg, sizeof(errmsg),
218 YY_("syntax error, unexpected expression, "
219 "expecting %s"), MODE_TO_STRING(parser_mode));
220 sdb_fe_yyerror(&yylloc, scanner, errmsg);
221 sdb_object_deref(SDB_OBJ($1));
222 YYABORT;
223 }
225 if ($1) {
226 sdb_conn_node_t *n;
227 n = SDB_CONN_NODE(sdb_object_create_dT(/* name = */ NULL,
228 conn_expr_t, conn_expr_destroy));
229 n->cmd = CONNECTION_EXPR;
230 CONN_EXPR($$)->expr = $1;
232 sdb_llist_append(pt, SDB_OBJ(n));
233 sdb_object_deref(SDB_OBJ(n));
234 }
235 }
236 ;
238 statement:
239 fetch_statement
240 |
241 list_statement
242 |
243 lookup_statement
244 |
245 timeseries_statement
246 |
247 /* empty */
248 {
249 $$ = NULL;
250 }
251 ;
253 /*
254 * FETCH <type> <hostname> [FILTER <condition>];
255 *
256 * Retrieve detailed information about a single host.
257 */
258 fetch_statement:
259 FETCH IDENTIFIER STRING filter_clause
260 {
261 /* TODO: support other types as well */
262 if (strcasecmp($2, "host")) {
263 char errmsg[strlen($2) + 32];
264 snprintf(errmsg, sizeof(errmsg),
265 YY_("unknown data-source %s"), $2);
266 sdb_fe_yyerror(&yylloc, scanner, errmsg);
267 free($2); $2 = NULL;
268 free($3); $3 = NULL;
269 sdb_object_deref(SDB_OBJ($4));
270 YYABORT;
271 }
273 $$ = SDB_CONN_NODE(sdb_object_create_dT(/* name = */ NULL,
274 conn_fetch_t, conn_fetch_destroy));
275 CONN_FETCH($$)->type = SDB_HOST;
276 CONN_FETCH($$)->name = $3;
277 CONN_FETCH($$)->filter = CONN_MATCHER($4);
278 $$->cmd = CONNECTION_FETCH;
279 free($2); $2 = NULL;
280 }
281 ;
283 /*
284 * LIST <type> [FILTER <condition>];
285 *
286 * Returns a list of all hosts in the store.
287 */
288 list_statement:
289 LIST IDENTIFIER filter_clause
290 {
291 int type = sdb_store_parse_object_type_plural($2);
292 if (type < 0) {
293 char errmsg[strlen($2) + 32];
294 snprintf(errmsg, sizeof(errmsg),
295 YY_("unknown data-source %s"), $2);
296 sdb_fe_yyerror(&yylloc, scanner, errmsg);
297 free($2); $2 = NULL;
298 sdb_object_deref(SDB_OBJ($3));
299 YYABORT;
300 }
302 $$ = SDB_CONN_NODE(sdb_object_create_dT(/* name = */ NULL,
303 conn_list_t, conn_list_destroy));
304 CONN_LIST($$)->type = type;
305 CONN_LIST($$)->filter = CONN_MATCHER($3);
306 $$->cmd = CONNECTION_LIST;
307 free($2); $2 = NULL;
308 }
309 ;
311 /*
312 * LOOKUP <type> MATCHING <condition> [FILTER <condition>];
313 *
314 * Returns detailed information about <type> matching condition.
315 */
316 lookup_statement:
317 LOOKUP IDENTIFIER matching_clause filter_clause
318 {
319 /* TODO: support other types as well */
320 if (strcasecmp($2, "hosts")) {
321 char errmsg[strlen($2) + 32];
322 snprintf(errmsg, sizeof(errmsg),
323 YY_("unknown data-source %s"), $2);
324 sdb_fe_yyerror(&yylloc, scanner, errmsg);
325 free($2); $2 = NULL;
326 sdb_object_deref(SDB_OBJ($3));
327 sdb_object_deref(SDB_OBJ($4));
328 YYABORT;
329 }
331 $$ = SDB_CONN_NODE(sdb_object_create_dT(/* name = */ NULL,
332 conn_lookup_t, conn_lookup_destroy));
333 CONN_LOOKUP($$)->type = SDB_HOST;
334 CONN_LOOKUP($$)->matcher = CONN_MATCHER($3);
335 CONN_LOOKUP($$)->filter = CONN_MATCHER($4);
336 $$->cmd = CONNECTION_LOOKUP;
337 free($2); $2 = NULL;
338 }
339 ;
341 matching_clause:
342 MATCHING condition { $$ = $2; }
343 |
344 /* empty */ { $$ = NULL; }
346 filter_clause:
347 FILTER condition { $$ = $2; }
348 |
349 /* empty */ { $$ = NULL; }
351 /*
352 * TIMESERIES <host>.<metric> [START <datetime>] [END <datetime>];
353 *
354 * Returns a time-series for the specified host's metric.
355 */
356 timeseries_statement:
357 TIMESERIES STRING '.' STRING start_clause end_clause
358 {
359 $$ = SDB_CONN_NODE(sdb_object_create_dT(/* name = */ NULL,
360 conn_ts_t, conn_ts_destroy));
361 CONN_TS($$)->hostname = $2;
362 CONN_TS($$)->metric = $4;
363 CONN_TS($$)->opts.start = $5;
364 CONN_TS($$)->opts.end = $6;
365 $$->cmd = CONNECTION_TIMESERIES;
366 }
367 ;
369 start_clause:
370 START datetime { $$ = $2; }
371 |
372 /* empty */ { $$ = sdb_gettime() - SDB_INTERVAL_HOUR; }
374 end_clause:
375 END datetime { $$ = $2; }
376 |
377 /* empty */ { $$ = sdb_gettime(); }
379 /*
380 * Basic expressions.
381 */
383 condition:
384 matcher
385 {
386 if (! $1) {
387 /* TODO: improve error reporting */
388 sdb_fe_yyerror(&yylloc, scanner,
389 YY_("syntax error, invalid condition"));
390 YYABORT;
391 }
393 $$ = SDB_CONN_NODE(sdb_object_create_dT(/* name = */ NULL,
394 conn_matcher_t, conn_matcher_destroy));
395 $$->cmd = CONNECTION_MATCHER;
396 CONN_MATCHER($$)->matcher = $1;
397 }
398 ;
400 matcher:
401 '(' matcher ')'
402 {
403 $$ = $2;
404 }
405 |
406 matcher AND matcher
407 {
408 $$ = sdb_store_con_matcher($1, $3);
409 sdb_object_deref(SDB_OBJ($1));
410 sdb_object_deref(SDB_OBJ($3));
411 }
412 |
413 matcher OR matcher
414 {
415 $$ = sdb_store_dis_matcher($1, $3);
416 sdb_object_deref(SDB_OBJ($1));
417 sdb_object_deref(SDB_OBJ($3));
418 }
419 |
420 NOT matcher
421 {
422 $$ = sdb_store_inv_matcher($2);
423 sdb_object_deref(SDB_OBJ($2));
424 }
425 |
426 compare_matcher
427 {
428 $$ = $1;
429 }
430 ;
432 /*
433 * <object_type>.<object_attr> <cmp> <value>
434 *
435 * Parse matchers comparing object attributes with a value.
436 */
437 compare_matcher:
438 '.' IDENTIFIER cmp expression
439 {
440 $$ = sdb_store_matcher_parse_field_cmp($2, $3, $4);
441 free($2); $2 = NULL;
442 sdb_object_deref(SDB_OBJ($4));
443 }
444 |
445 IDENTIFIER cmp expression
446 {
447 $$ = sdb_store_matcher_parse_cmp($1, NULL, $2, $3);
448 free($1); $1 = NULL;
449 sdb_object_deref(SDB_OBJ($3));
450 }
451 |
452 IDENTIFIER '[' IDENTIFIER ']' cmp expression
453 {
454 $$ = sdb_store_matcher_parse_cmp($1, $3, $5, $6);
455 free($1); $1 = NULL;
456 free($3); $3 = NULL;
457 sdb_object_deref(SDB_OBJ($6));
458 }
459 |
460 IDENTIFIER '[' IDENTIFIER ']' IS NULL_T
461 {
462 $$ = sdb_store_matcher_parse_cmp($1, $3, "IS", NULL);
463 free($1); $1 = NULL;
464 free($3); $3 = NULL;
465 }
466 |
467 IDENTIFIER '[' IDENTIFIER ']' IS NOT NULL_T
468 {
469 sdb_store_matcher_t *m;
470 m = sdb_store_matcher_parse_cmp($1, $3, "IS", NULL);
471 free($1); $1 = NULL;
472 free($3); $3 = NULL;
474 /* sdb_store_inv_matcher return NULL if m==NULL */
475 $$ = sdb_store_inv_matcher(m);
476 sdb_object_deref(SDB_OBJ(m));
477 }
478 ;
480 expression:
481 '(' expression ')'
482 {
483 $$ = $2;
484 }
485 |
486 expression '+' expression
487 {
488 $$ = sdb_store_expr_create(SDB_DATA_ADD, $1, $3);
489 sdb_object_deref(SDB_OBJ($1)); $1 = NULL;
490 sdb_object_deref(SDB_OBJ($3)); $3 = NULL;
491 }
492 |
493 expression '-' expression
494 {
495 $$ = sdb_store_expr_create(SDB_DATA_SUB, $1, $3);
496 sdb_object_deref(SDB_OBJ($1)); $1 = NULL;
497 sdb_object_deref(SDB_OBJ($3)); $3 = NULL;
498 }
499 |
500 expression '*' expression
501 {
502 $$ = sdb_store_expr_create(SDB_DATA_MUL, $1, $3);
503 sdb_object_deref(SDB_OBJ($1)); $1 = NULL;
504 sdb_object_deref(SDB_OBJ($3)); $3 = NULL;
505 }
506 |
507 expression '/' expression
508 {
509 $$ = sdb_store_expr_create(SDB_DATA_DIV, $1, $3);
510 sdb_object_deref(SDB_OBJ($1)); $1 = NULL;
511 sdb_object_deref(SDB_OBJ($3)); $3 = NULL;
512 }
513 |
514 expression '%' expression
515 {
516 $$ = sdb_store_expr_create(SDB_DATA_MOD, $1, $3);
517 sdb_object_deref(SDB_OBJ($1)); $1 = NULL;
518 sdb_object_deref(SDB_OBJ($3)); $3 = NULL;
519 }
520 |
521 expression CONCAT expression
522 {
523 $$ = sdb_store_expr_create(SDB_DATA_CONCAT, $1, $3);
524 sdb_object_deref(SDB_OBJ($1)); $1 = NULL;
525 sdb_object_deref(SDB_OBJ($3)); $3 = NULL;
526 }
527 |
528 '.' IDENTIFIER
529 {
530 int field = sdb_store_parse_field_name($2);
531 free($2); $2 = NULL;
532 $$ = sdb_store_expr_fieldvalue(field);
533 }
534 |
535 IDENTIFIER '[' IDENTIFIER ']'
536 {
537 $$ = sdb_store_expr_attrvalue($3);
538 free($1); $1 = NULL;
539 free($3); $3 = NULL;
540 }
541 |
542 data
543 {
544 $$ = sdb_store_expr_constvalue(&$1);
545 sdb_data_free_datum(&$1);
546 }
547 ;
549 cmp:
550 CMP_EQUAL { $$ = "="; }
551 |
552 CMP_NEQUAL { $$ = "!="; }
553 |
554 CMP_REGEX { $$ = "=~"; }
555 |
556 CMP_NREGEX { $$ = "!~"; }
557 |
558 CMP_LT { $$ = "<"; }
559 |
560 CMP_LE { $$ = "<="; }
561 |
562 CMP_GE { $$ = ">="; }
563 |
564 CMP_GT { $$ = ">"; }
565 ;
567 data:
568 STRING { $$.type = SDB_TYPE_STRING; $$.data.string = $1; }
569 |
570 INTEGER { $$ = $1; }
571 |
572 FLOAT { $$ = $1; }
573 |
574 datetime { $$.type = SDB_TYPE_DATETIME; $$.data.datetime = $1; }
575 |
576 interval { $$ = $1; }
577 ;
579 datetime:
580 DATE TIME { $$ = $1 + $2; }
581 |
582 DATE { $$ = $1; }
583 |
584 TIME { $$ = $1; }
585 ;
587 interval:
588 interval interval_elem
589 {
590 $$.data.datetime = $1.data.datetime + $2.data.datetime;
591 }
592 |
593 interval_elem { $$ = $1; }
594 ;
596 interval_elem:
597 INTEGER IDENTIFIER
598 {
599 sdb_time_t unit = 1;
601 unit = sdb_strpunit($2);
602 if (! unit) {
603 char errmsg[strlen($2) + 32];
604 snprintf(errmsg, sizeof(errmsg),
605 YY_("invalid time unit %s"), $2);
606 sdb_fe_yyerror(&yylloc, scanner, errmsg);
607 free($2); $2 = NULL;
608 YYABORT;
609 }
610 free($2); $2 = NULL;
612 $$.type = SDB_TYPE_DATETIME;
613 $$.data.datetime = (sdb_time_t)$1.data.integer * unit;
615 if ($1.data.integer < 0) {
616 sdb_fe_yyerror(&yylloc, scanner,
617 YY_("syntax error, negative intervals not supported"));
618 YYABORT;
619 }
620 }
621 ;
623 %%
625 void
626 sdb_fe_yyerror(YYLTYPE *lval, sdb_fe_yyscan_t scanner, const char *msg)
627 {
628 sdb_log(SDB_LOG_ERR, "frontend: parse error: %s", msg);
629 } /* sdb_fe_yyerror */
631 /* vim: set tw=78 sw=4 ts=4 noexpandtab : */