src/frontend/grammar.y

   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  */
  27
  28 %{
  29
  30 #include "frontend/connection-private.h"
  31 #include "frontend/parser.h"
  32 #include "frontend/grammar.h"
  33
  34 #include "core/store.h"
  35 #include "core/store-private.h"
  36 #include "core/time.h"
  37
  38 #include "utils/error.h"
  39 #include "utils/llist.h"
  40
  41 #include <assert.h>
  42
  43 #include <stdio.h>
  44 #include <string.h>
  45
  46 /*
  47  * private helper functions
  48  */
  49
  50 static sdb_store_matcher_t *
  51 name_iter_matcher(int m_type, const char *type_name, const char *cmp,
  52                 sdb_store_expr_t *expr);
  53
  54 /*
  55  * public API
  56  */
  57
  58 int
  59 sdb_fe_yylex(YYSTYPE *yylval, YYLTYPE *yylloc, sdb_fe_yyscan_t yyscanner);
  60
  61 sdb_fe_yyextra_t *
  62 sdb_fe_yyget_extra(sdb_fe_yyscan_t scanner);
  63
  64 void
  65 sdb_fe_yyerror(YYLTYPE *lval, sdb_fe_yyscan_t scanner, const char *msg);
  66
  67 /* quick access to the current parse tree */
  68 #define pt sdb_fe_yyget_extra(scanner)->parsetree
  69
  70 /* quick access to the parser mode */
  71 #define parser_mode sdb_fe_yyget_extra(scanner)->mode
  72
  73 #define MODE_TO_STRING(m) \
  74         (((m) == SDB_PARSE_DEFAULT) ? "statement" \
  75                 : ((m) == SDB_PARSE_COND) ? "condition" \
  76                 : ((m) == SDB_PARSE_EXPR) ? "expression" \
  77                 : "UNKNOWN")
  78
  79 %}
  80
  81 %pure-parser
  82 %lex-param {sdb_fe_yyscan_t scanner}
  83 %parse-param {sdb_fe_yyscan_t scanner}
  84 %locations
  85 %error-verbose
  86 %expect 0
  87 %name-prefix "sdb_fe_yy"
  88
  89 %union {
  90         const char *sstr; /* static string */
  91         char *str;
  92
  93         sdb_data_t data;
  94         sdb_time_t datetime;
  95
  96         sdb_llist_t     *list;
  97         sdb_conn_node_t *node;
  98
  99         sdb_store_matcher_t *m;
 100         sdb_store_expr_t *expr;
 101 }
 102
 103 %start statements
 104
 105 %token SCANNER_ERROR
 106
 107 %token AND OR IS NOT MATCHING FILTER
 108 %token CMP_EQUAL CMP_NEQUAL CMP_REGEX CMP_NREGEX
 109 %token CMP_LT CMP_LE CMP_GE CMP_GT ALL ANY IN
 110 %token CONCAT
 111
 112 %token START END
 113
 114 /* NULL token */
 115 %token NULL_T
 116
 117 %token FETCH LIST LOOKUP TIMESERIES
 118
 119 %token <str> IDENTIFIER STRING
 120
 121 %token <data> INTEGER FLOAT
 122
 123 %token <datetime> DATE TIME
 124
 125 /* Precedence (lowest first): */
 126 %left OR
 127 %left AND
 128 %right NOT
 129 %left CMP_EQUAL CMP_NEQUAL
 130 %left CMP_LT CMP_LE CMP_GE CMP_GT
 131 %nonassoc CMP_REGEX CMP_NREGEX
 132 %nonassoc IN
 133 %left CONCAT
 134 %nonassoc IS
 135 %left '+' '-'
 136 %left '*' '/' '%'
 137 %left '[' ']'
 138 %left '(' ')'
 139 %left '.'
 140
 141 %type <list> statements
 142 %type <node> statement
 143         fetch_statement
 144         list_statement
 145         lookup_statement
 146         timeseries_statement
 147         matching_clause
 148         filter_clause
 149         condition
 150
 151 %type <m> matcher
 152         compare_matcher
 153
 154 %type <expr> expression
 155
 156 %type <sstr> cmp
 157
 158 %type <data> data
 159         interval interval_elem
 160
 161 %type <datetime> datetime
 162         start_clause end_clause
 163
 164 %destructor { free($$); } <str>
 165 %destructor { sdb_object_deref(SDB_OBJ($$)); } <node> <m> <expr>
 166 %destructor { sdb_data_free_datum(&$$); } <data>
 167
 168 %%
 169
 170 statements:
 171         statements ';' statement
 172                 {
 173                         /* only accepted in default parse mode */
 174                         if (parser_mode != SDB_PARSE_DEFAULT) {
 175                                 char errmsg[1024];
 176                                 snprintf(errmsg, sizeof(errmsg),
 177                                                 YY_("syntax error, unexpected statement, "
 178                                                         "expecting %s"), MODE_TO_STRING(parser_mode));
 179                                 sdb_fe_yyerror(&yylloc, scanner, errmsg);
 180                                 sdb_object_deref(SDB_OBJ($3));
 181                                 YYABORT;
 182                         }
 183
 184                         if ($3) {
 185                                 sdb_llist_append(pt, SDB_OBJ($3));
 186                                 sdb_object_deref(SDB_OBJ($3));
 187                         }
 188                 }
 189         |
 190         statement
 191                 {
 192                         /* only accepted in default parse mode */
 193                         if (parser_mode != SDB_PARSE_DEFAULT) {
 194                                 char errmsg[1024];
 195                                 snprintf(errmsg, sizeof(errmsg),
 196                                                 YY_("syntax error, unexpected statement, "
 197                                                         "expecting %s"), MODE_TO_STRING(parser_mode));
 198                                 sdb_fe_yyerror(&yylloc, scanner, errmsg);
 199                                 sdb_object_deref(SDB_OBJ($1));
 200                                 YYABORT;
 201                         }
 202
 203                         if ($1) {
 204                                 sdb_llist_append(pt, SDB_OBJ($1));
 205                                 sdb_object_deref(SDB_OBJ($1));
 206                         }
 207                 }
 208         |
 209         condition
 210                 {
 211                         /* only accepted in condition parse mode */
 212                         if (! (parser_mode & SDB_PARSE_COND)) {
 213                                 char errmsg[1024];
 214                                 snprintf(errmsg, sizeof(errmsg),
 215                                                 YY_("syntax error, unexpected condition, "
 216                                                         "expecting %s"), MODE_TO_STRING(parser_mode));
 217                                 sdb_fe_yyerror(&yylloc, scanner, errmsg);
 218                                 sdb_object_deref(SDB_OBJ($1));
 219                                 YYABORT;
 220                         }
 221
 222                         if ($1) {
 223                                 sdb_llist_append(pt, SDB_OBJ($1));
 224                                 sdb_object_deref(SDB_OBJ($1));
 225                         }
 226                 }
 227         |
 228         expression
 229                 {
 230                         /* only accepted in expression parse mode */
 231                         if (! (parser_mode & SDB_PARSE_EXPR)) {
 232                                 char errmsg[1024];
 233                                 snprintf(errmsg, sizeof(errmsg),
 234                                                 YY_("syntax error, unexpected expression, "
 235                                                         "expecting %s"), MODE_TO_STRING(parser_mode));
 236                                 sdb_fe_yyerror(&yylloc, scanner, errmsg);
 237                                 sdb_object_deref(SDB_OBJ($1));
 238                                 YYABORT;
 239                         }
 240
 241                         if ($1) {
 242                                 sdb_conn_node_t *n;
 243                                 n = SDB_CONN_NODE(sdb_object_create_dT(/* name = */ NULL,
 244                                                         conn_expr_t, conn_expr_destroy));
 245                                 n->cmd = CONNECTION_EXPR;
 246                                 CONN_EXPR(n)->expr = $1;
 247
 248                                 sdb_llist_append(pt, SDB_OBJ(n));
 249                                 sdb_object_deref(SDB_OBJ(n));
 250                         }
 251                 }
 252         ;
 253
 254 statement:
 255         fetch_statement
 256         |
 257         list_statement
 258         |
 259         lookup_statement
 260         |
 261         timeseries_statement
 262         |
 263         /* empty */
 264                 {
 265                         $$ = NULL;
 266                 }
 267         ;
 268
 269 /*
 270  * FETCH <type> <hostname> [FILTER <condition>];
 271  *
 272  * Retrieve detailed information about a single host.
 273  */
 274 fetch_statement:
 275         FETCH IDENTIFIER STRING filter_clause
 276                 {
 277                         /* TODO: support other types as well */
 278                         if (strcasecmp($2, "host")) {
 279                                 char errmsg[strlen($2) + 32];
 280                                 snprintf(errmsg, sizeof(errmsg),
 281                                                 YY_("unknown data-source %s"), $2);
 282                                 sdb_fe_yyerror(&yylloc, scanner, errmsg);
 283                                 free($2); $2 = NULL;
 284                                 free($3); $3 = NULL;
 285                                 sdb_object_deref(SDB_OBJ($4));
 286                                 YYABORT;
 287                         }
 288
 289                         $$ = SDB_CONN_NODE(sdb_object_create_dT(/* name = */ NULL,
 290                                                 conn_fetch_t, conn_fetch_destroy));
 291                         CONN_FETCH($$)->type = SDB_HOST;
 292                         CONN_FETCH($$)->name = $3;
 293                         CONN_FETCH($$)->filter = CONN_MATCHER($4);
 294                         $$->cmd = CONNECTION_FETCH;
 295                         free($2); $2 = NULL;
 296                 }
 297         ;
 298
 299 /*
 300  * LIST <type> [FILTER <condition>];
 301  *
 302  * Returns a list of all hosts in the store.
 303  */
 304 list_statement:
 305         LIST IDENTIFIER filter_clause
 306                 {
 307                         int type = sdb_store_parse_object_type_plural($2);
 308                         if ((type < 0) || (type == SDB_ATTRIBUTE)) {
 309                                 char errmsg[strlen($2) + 32];
 310                                 snprintf(errmsg, sizeof(errmsg),
 311                                                 YY_("unknown data-source %s"), $2);
 312                                 sdb_fe_yyerror(&yylloc, scanner, errmsg);
 313                                 free($2); $2 = NULL;
 314                                 sdb_object_deref(SDB_OBJ($3));
 315                                 YYABORT;
 316                         }
 317
 318                         $$ = SDB_CONN_NODE(sdb_object_create_dT(/* name = */ NULL,
 319                                                 conn_list_t, conn_list_destroy));
 320                         CONN_LIST($$)->type = type;
 321                         CONN_LIST($$)->filter = CONN_MATCHER($3);
 322                         $$->cmd = CONNECTION_LIST;
 323                         free($2); $2 = NULL;
 324                 }
 325         ;
 326
 327 /*
 328  * LOOKUP <type> MATCHING <condition> [FILTER <condition>];
 329  *
 330  * Returns detailed information about <type> matching condition.
 331  */
 332 lookup_statement:
 333         LOOKUP IDENTIFIER matching_clause filter_clause
 334                 {
 335                         /* TODO: support other types as well */
 336                         if (strcasecmp($2, "hosts")) {
 337                                 char errmsg[strlen($2) + 32];
 338                                 snprintf(errmsg, sizeof(errmsg),
 339                                                 YY_("unknown data-source %s"), $2);
 340                                 sdb_fe_yyerror(&yylloc, scanner, errmsg);
 341                                 free($2); $2 = NULL;
 342                                 sdb_object_deref(SDB_OBJ($3));
 343                                 sdb_object_deref(SDB_OBJ($4));
 344                                 YYABORT;
 345                         }
 346
 347                         $$ = SDB_CONN_NODE(sdb_object_create_dT(/* name = */ NULL,
 348                                                 conn_lookup_t, conn_lookup_destroy));
 349                         CONN_LOOKUP($$)->type = SDB_HOST;
 350                         CONN_LOOKUP($$)->matcher = CONN_MATCHER($3);
 351                         CONN_LOOKUP($$)->filter = CONN_MATCHER($4);
 352                         $$->cmd = CONNECTION_LOOKUP;
 353                         free($2); $2 = NULL;
 354                 }
 355         ;
 356
 357 matching_clause:
 358         MATCHING condition { $$ = $2; }
 359         |
 360         /* empty */ { $$ = NULL; }
 361
 362 filter_clause:
 363         FILTER condition { $$ = $2; }
 364         |
 365         /* empty */ { $$ = NULL; }
 366
 367 /*
 368  * TIMESERIES <host>.<metric> [START <datetime>] [END <datetime>];
 369  *
 370  * Returns a time-series for the specified host's metric.
 371  */
 372 timeseries_statement:
 373         TIMESERIES STRING '.' STRING start_clause end_clause
 374                 {
 375                         $$ = SDB_CONN_NODE(sdb_object_create_dT(/* name = */ NULL,
 376                                                 conn_ts_t, conn_ts_destroy));
 377                         CONN_TS($$)->hostname = $2;
 378                         CONN_TS($$)->metric = $4;
 379                         CONN_TS($$)->opts.start = $5;
 380                         CONN_TS($$)->opts.end = $6;
 381                         $$->cmd = CONNECTION_TIMESERIES;
 382                 }
 383         ;
 384
 385 start_clause:
 386         START datetime { $$ = $2; }
 387         |
 388         /* empty */ { $$ = sdb_gettime() - SDB_INTERVAL_HOUR; }
 389
 390 end_clause:
 391         END datetime { $$ = $2; }
 392         |
 393         /* empty */ { $$ = sdb_gettime(); }
 394
 395 /*
 396  * Basic expressions.
 397  */
 398
 399 condition:
 400         matcher
 401                 {
 402                         if (! $1) {
 403                                 /* TODO: improve error reporting */
 404                                 sdb_fe_yyerror(&yylloc, scanner,
 405                                                 YY_("syntax error, invalid condition"));
 406                                 YYABORT;
 407                         }
 408
 409                         $$ = SDB_CONN_NODE(sdb_object_create_dT(/* name = */ NULL,
 410                                                 conn_matcher_t, conn_matcher_destroy));
 411                         $$->cmd = CONNECTION_MATCHER;
 412                         CONN_MATCHER($$)->matcher = $1;
 413                 }
 414         ;
 415
 416 matcher:
 417         '(' matcher ')'
 418                 {
 419                         $$ = $2;
 420                 }
 421         |
 422         matcher AND matcher
 423                 {
 424                         $$ = sdb_store_con_matcher($1, $3);
 425                         sdb_object_deref(SDB_OBJ($1));
 426                         sdb_object_deref(SDB_OBJ($3));
 427                 }
 428         |
 429         matcher OR matcher
 430                 {
 431                         $$ = sdb_store_dis_matcher($1, $3);
 432                         sdb_object_deref(SDB_OBJ($1));
 433                         sdb_object_deref(SDB_OBJ($3));
 434                 }
 435         |
 436         NOT matcher
 437                 {
 438                         $$ = sdb_store_inv_matcher($2);
 439                         sdb_object_deref(SDB_OBJ($2));
 440                 }
 441         |
 442         compare_matcher
 443                 {
 444                         $$ = $1;
 445                 }
 446         ;
 447
 448 compare_matcher:
 449         expression cmp expression
 450                 {
 451                         sdb_store_matcher_op_cb cb = sdb_store_parse_matcher_op($2);
 452                         assert(cb); /* else, the grammar accepts invalid 'cmp' */
 453                         $$ = cb($1, $3);
 454                         sdb_object_deref(SDB_OBJ($1));
 455                         sdb_object_deref(SDB_OBJ($3));
 456                 }
 457         |
 458         ANY IDENTIFIER cmp expression
 459                 {
 460                         $$ = name_iter_matcher(MATCHER_ANY, $2, $3, $4);
 461                         free($2); $2 = NULL;
 462                         sdb_object_deref(SDB_OBJ($4));
 463                 }
 464         |
 465         ALL IDENTIFIER cmp expression
 466                 {
 467                         $$ = name_iter_matcher(MATCHER_ALL, $2, $3, $4);
 468                         free($2); $2 = NULL;
 469                         sdb_object_deref(SDB_OBJ($4));
 470                 }
 471         |
 472         expression IS NULL_T
 473                 {
 474                         $$ = sdb_store_isnull_matcher($1);
 475                         sdb_object_deref(SDB_OBJ($1));
 476                 }
 477         |
 478         expression IS NOT NULL_T
 479                 {
 480                         $$ = sdb_store_isnnull_matcher($1);
 481                         sdb_object_deref(SDB_OBJ($1));
 482                 }
 483         |
 484         expression IN expression
 485                 {
 486                         $$ = sdb_store_in_matcher($1, $3);
 487                         sdb_object_deref(SDB_OBJ($1));
 488                         sdb_object_deref(SDB_OBJ($3));
 489                 }
 490         ;
 491
 492 expression:
 493         '(' expression ')'
 494                 {
 495                         $$ = $2;
 496                 }
 497         |
 498         expression '+' expression
 499                 {
 500                         $$ = sdb_store_expr_create(SDB_DATA_ADD, $1, $3);
 501                         sdb_object_deref(SDB_OBJ($1)); $1 = NULL;
 502                         sdb_object_deref(SDB_OBJ($3)); $3 = NULL;
 503                 }
 504         |
 505         expression '-' expression
 506                 {
 507                         $$ = sdb_store_expr_create(SDB_DATA_SUB, $1, $3);
 508                         sdb_object_deref(SDB_OBJ($1)); $1 = NULL;
 509                         sdb_object_deref(SDB_OBJ($3)); $3 = NULL;
 510                 }
 511         |
 512         expression '*' expression
 513                 {
 514                         $$ = sdb_store_expr_create(SDB_DATA_MUL, $1, $3);
 515                         sdb_object_deref(SDB_OBJ($1)); $1 = NULL;
 516                         sdb_object_deref(SDB_OBJ($3)); $3 = NULL;
 517                 }
 518         |
 519         expression '/' expression
 520                 {
 521                         $$ = sdb_store_expr_create(SDB_DATA_DIV, $1, $3);
 522                         sdb_object_deref(SDB_OBJ($1)); $1 = NULL;
 523                         sdb_object_deref(SDB_OBJ($3)); $3 = NULL;
 524                 }
 525         |
 526         expression '%' expression
 527                 {
 528                         $$ = sdb_store_expr_create(SDB_DATA_MOD, $1, $3);
 529                         sdb_object_deref(SDB_OBJ($1)); $1 = NULL;
 530                         sdb_object_deref(SDB_OBJ($3)); $3 = NULL;
 531                 }
 532         |
 533         expression CONCAT expression
 534                 {
 535                         $$ = sdb_store_expr_create(SDB_DATA_CONCAT, $1, $3);
 536                         sdb_object_deref(SDB_OBJ($1)); $1 = NULL;
 537                         sdb_object_deref(SDB_OBJ($3)); $3 = NULL;
 538                 }
 539         |
 540         IDENTIFIER
 541                 {
 542                         int field;
 543                         /* TODO: this only works as long as queries
 544                          * are limited to hosts */
 545                         if (!strcasecmp($1, "host"))
 546                                 field = SDB_FIELD_NAME;
 547                         else
 548                                 field = sdb_store_parse_field_name($1);
 549                         free($1); $1 = NULL;
 550                         $$ = sdb_store_expr_fieldvalue(field);
 551                 }
 552         |
 553         IDENTIFIER '[' STRING ']'
 554                 {
 555                         if (strcasecmp($1, "attribute")) {
 556                                 char errmsg[strlen($1) + strlen($3) + 32];
 557                                 snprintf(errmsg, sizeof(errmsg),
 558                                                 YY_("unknown value %s[%s]"), $1, $3);
 559                                 sdb_fe_yyerror(&yylloc, scanner, errmsg);
 560                                 free($1); $1 = NULL;
 561                                 free($3); $3 = NULL;
 562                                 YYABORT;
 563                         }
 564                         $$ = sdb_store_expr_attrvalue($3);
 565                         free($1); $1 = NULL;
 566                         free($3); $3 = NULL;
 567                 }
 568         |
 569         data
 570                 {
 571                         $$ = sdb_store_expr_constvalue(&$1);
 572                         sdb_data_free_datum(&$1);
 573                 }
 574         ;
 575
 576 cmp:
 577         CMP_EQUAL { $$ = "="; }
 578         |
 579         CMP_NEQUAL { $$ = "!="; }
 580         |
 581         CMP_REGEX { $$ = "=~"; }
 582         |
 583         CMP_NREGEX { $$ = "!~"; }
 584         |
 585         CMP_LT { $$ = "<"; }
 586         |
 587         CMP_LE { $$ = "<="; }
 588         |
 589         CMP_GE { $$ = ">="; }
 590         |
 591         CMP_GT { $$ = ">"; }
 592         ;
 593
 594 data:
 595         STRING { $$.type = SDB_TYPE_STRING; $$.data.string = $1; }
 596         |
 597         INTEGER { $$ = $1; }
 598         |
 599         FLOAT { $$ = $1; }
 600         |
 601         datetime { $$.type = SDB_TYPE_DATETIME; $$.data.datetime = $1; }
 602         |
 603         interval { $$ = $1; }
 604         ;
 605
 606 datetime:
 607         DATE TIME { $$ = $1 + $2; }
 608         |
 609         DATE { $$ = $1; }
 610         |
 611         TIME { $$ = $1; }
 612         ;
 613
 614 interval:
 615         interval interval_elem
 616                 {
 617                         $$.data.datetime = $1.data.datetime + $2.data.datetime;
 618                 }
 619         |
 620         interval_elem { $$ = $1; }
 621         ;
 622
 623 interval_elem:
 624         INTEGER IDENTIFIER
 625                 {
 626                         sdb_time_t unit = 1;
 627
 628                         unit = sdb_strpunit($2);
 629                         if (! unit) {
 630                                 char errmsg[strlen($2) + 32];
 631                                 snprintf(errmsg, sizeof(errmsg),
 632                                                 YY_("invalid time unit %s"), $2);
 633                                 sdb_fe_yyerror(&yylloc, scanner, errmsg);
 634                                 free($2); $2 = NULL;
 635                                 YYABORT;
 636                         }
 637                         free($2); $2 = NULL;
 638
 639                         $$.type = SDB_TYPE_DATETIME;
 640                         $$.data.datetime = (sdb_time_t)$1.data.integer * unit;
 641
 642                         if ($1.data.integer < 0) {
 643                                 sdb_fe_yyerror(&yylloc, scanner,
 644                                                 YY_("syntax error, negative intervals not supported"));
 645                                 YYABORT;
 646                         }
 647                 }
 648         ;
 649
 650 %%
 651
 652 void
 653 sdb_fe_yyerror(YYLTYPE *lval, sdb_fe_yyscan_t scanner, const char *msg)
 654 {
 655         sdb_log(SDB_LOG_ERR, "frontend: parse error: %s", msg);
 656 } /* sdb_fe_yyerror */
 657
 658 static sdb_store_matcher_t *
 659 name_iter_matcher(int m_type, const char *type_name, const char *cmp,
 660                 sdb_store_expr_t *expr)
 661 {
 662         int type = sdb_store_parse_object_type(type_name);
 663         sdb_store_matcher_op_cb cb = sdb_store_parse_matcher_op(cmp);
 664         sdb_store_expr_t *e;
 665         sdb_store_matcher_t *m, *tmp = NULL;
 666         assert(cb);
 667
 668         /* TODO: this only works as long as queries
 669          * are limited to hosts */
 670         if (type == SDB_HOST) {
 671                 return NULL;
 672         }
 673
 674         e = sdb_store_expr_fieldvalue(SDB_FIELD_NAME);
 675         m = cb(e, expr);
 676         if (m_type == MATCHER_ANY)
 677                 tmp = sdb_store_any_matcher(type, m);
 678         else if (m_type == MATCHER_ALL)
 679                 tmp = sdb_store_all_matcher(type, m);
 680         sdb_object_deref(SDB_OBJ(m));
 681         sdb_object_deref(SDB_OBJ(e));
 682         return tmp;
 683 } /* name_iter_matcher */
 684
 685 /* vim: set tw=78 sw=4 ts=4 noexpandtab : */
 686