src/frontend/parser.c

   1 /*
   2  * SysDB - src/frontend/parser.c
   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 #include "sysdb.h"
  29
  30 #include "frontend/connection-private.h"
  31 #include "frontend/parser.h"
  32 #include "frontend/grammar.h"
  33
  34 #include "core/store.h"
  35
  36 #include "utils/llist.h"
  37
  38 #include <string.h>
  39
  40 /*
  41  * private helper functions
  42  */
  43
  44 static int
  45 scanner_init(const char *input, int len,
  46                 sdb_fe_yyscan_t *scanner, sdb_fe_yyextra_t *extra)
  47 {
  48         if (! input)
  49                 return -1;
  50
  51         memset(extra, 0, sizeof(*extra));
  52         extra->parsetree = sdb_llist_create();
  53         extra->mode = SDB_PARSE_DEFAULT;
  54
  55         if (! extra->parsetree)
  56                 return -1;
  57
  58         *scanner = sdb_fe_scanner_init(input, len, extra);
  59         if (! scanner) {
  60                 sdb_llist_destroy(extra->parsetree);
  61                 return -1;
  62         }
  63         return 0;
  64 } /* scanner_init */
  65
  66 /*
  67  * public API
  68  */
  69
  70 sdb_llist_t *
  71 sdb_fe_parse(const char *query, int len)
  72 {
  73         sdb_fe_yyscan_t scanner;
  74         sdb_fe_yyextra_t yyextra;
  75         sdb_llist_iter_t *iter;
  76         int yyres;
  77
  78         if (scanner_init(query, len, &scanner, &yyextra))
  79                 return NULL;
  80
  81         yyres = sdb_fe_yyparse(scanner);
  82         sdb_fe_scanner_destroy(scanner);
  83
  84         if (yyres) {
  85                 sdb_llist_destroy(yyextra.parsetree);
  86                 return NULL;
  87         }
  88
  89         iter = sdb_llist_get_iter(yyextra.parsetree);
  90         while (sdb_llist_iter_has_next(iter)) {
  91                 sdb_conn_node_t *node;
  92                 node = SDB_CONN_NODE(sdb_llist_iter_get_next(iter));
  93                 if (sdb_fe_analyze(node)) {
  94                         sdb_llist_iter_destroy(iter);
  95                         sdb_llist_destroy(yyextra.parsetree);
  96                         return NULL;
  97                 }
  98         }
  99         sdb_llist_iter_destroy(iter);
 100         return yyextra.parsetree;
 101 } /* sdb_fe_parse */
 102
 103 sdb_store_matcher_t *
 104 sdb_fe_parse_matcher(const char *cond, int len)
 105 {
 106         sdb_fe_yyscan_t scanner;
 107         sdb_fe_yyextra_t yyextra;
 108
 109         sdb_conn_node_t *node;
 110         sdb_store_matcher_t *m;
 111
 112         int yyres;
 113
 114         if (scanner_init(cond, len, &scanner, &yyextra))
 115                 return NULL;
 116
 117         yyextra.mode = SDB_PARSE_COND;
 118
 119         yyres = sdb_fe_yyparse(scanner);
 120         sdb_fe_scanner_destroy(scanner);
 121
 122         if (yyres) {
 123                 sdb_llist_destroy(yyextra.parsetree);
 124                 return NULL;
 125         }
 126
 127         node = SDB_CONN_NODE(sdb_llist_get(yyextra.parsetree, 0));
 128         if (! node) {
 129                 sdb_llist_destroy(yyextra.parsetree);
 130                 return NULL;
 131         }
 132
 133         if (node->cmd == CONNECTION_MATCHER) {
 134                 m = CONN_MATCHER(node)->matcher;
 135                 CONN_MATCHER(node)->matcher = NULL;
 136         }
 137         else
 138                 m = NULL;
 139
 140         sdb_llist_destroy(yyextra.parsetree);
 141         sdb_object_deref(SDB_OBJ(node));
 142         return m;
 143 } /* sdb_fe_parse_matcher */
 144
 145 sdb_store_expr_t *
 146 sdb_fe_parse_expr(const char *expr, int len)
 147 {
 148         sdb_fe_yyscan_t scanner;
 149         sdb_fe_yyextra_t yyextra;
 150
 151         sdb_conn_node_t *node;
 152         sdb_store_expr_t *e;
 153
 154         int yyres;
 155
 156         if (scanner_init(expr, len, &scanner, &yyextra))
 157                 return NULL;
 158
 159         yyextra.mode = SDB_PARSE_EXPR;
 160
 161         yyres = sdb_fe_yyparse(scanner);
 162         sdb_fe_scanner_destroy(scanner);
 163
 164         if (yyres) {
 165                 sdb_llist_destroy(yyextra.parsetree);
 166                 return NULL;
 167         }
 168
 169         node = SDB_CONN_NODE(sdb_llist_get(yyextra.parsetree, 0));
 170         if (! node) {
 171                 sdb_llist_destroy(yyextra.parsetree);
 172                 return NULL;
 173         }
 174
 175         if (node->cmd == CONNECTION_EXPR) {
 176                 e = CONN_EXPR(node)->expr;
 177                 CONN_EXPR(node)->expr = NULL;
 178         }
 179         else
 180                 e = NULL;
 181
 182         sdb_llist_destroy(yyextra.parsetree);
 183         sdb_object_deref(SDB_OBJ(node));
 184         return e;
 185 } /* sdb_fe_parse_expr */
 186
 187 /* vim: set tw=78 sw=4 ts=4 noexpandtab : */
 188