contrib/ltree/ltxtquery_op.c

   1 /*
   2  * txtquery operations with ltree
   3  * Teodor Sigaev <teodor@stack.net>
   4  * $PostgreSQL$
   5  */
   6 #include "postgres.h"
   7
   8 #include <ctype.h>
   9
  10 #include "ltree.h"
  11
  12 PG_FUNCTION_INFO_V1(ltxtq_exec);
  13 PG_FUNCTION_INFO_V1(ltxtq_rexec);
  14
  15 /*
  16  * check for boolean condition
  17  */
  18 bool
  19 ltree_execute(ITEM *curitem, void *checkval, bool calcnot, bool (*chkcond) (void *checkval, ITEM *val))
  20 {
  21         if (curitem->type == VAL)
  22                 return (*chkcond) (checkval, curitem);
  23         else if (curitem->val == (int4) '!')
  24         {
  25                 return (calcnot) ?
  26                         ((ltree_execute(curitem + 1, checkval, calcnot, chkcond)) ? false : true)
  27                         : true;
  28         }
  29         else if (curitem->val == (int4) '&')
  30         {
  31                 if (ltree_execute(curitem + curitem->left, checkval, calcnot, chkcond))
  32                         return ltree_execute(curitem + 1, checkval, calcnot, chkcond);
  33                 else
  34                         return false;
  35         }
  36         else
  37         {                                                       /* |-operator */
  38                 if (ltree_execute(curitem + curitem->left, checkval, calcnot, chkcond))
  39                         return true;
  40                 else
  41                         return ltree_execute(curitem + 1, checkval, calcnot, chkcond);
  42         }
  43         return false;
  44 }
  45
  46 typedef struct
  47 {
  48         ltree      *node;
  49         char       *operand;
  50 } CHKVAL;
  51
  52 static bool
  53 checkcondition_str(void *checkval, ITEM *val)
  54 {
  55         ltree_level *level = LTREE_FIRST(((CHKVAL *) checkval)->node);
  56         int                     tlen = ((CHKVAL *) checkval)->node->numlevel;
  57         char       *op = ((CHKVAL *) checkval)->operand + val->distance;
  58         int                     (*cmpptr) (const char *, const char *, size_t);
  59
  60         cmpptr = (val->flag & LVAR_INCASE) ? ltree_strncasecmp : strncmp;
  61         while (tlen > 0)
  62         {
  63                 if (val->flag & LVAR_SUBLEXEME)
  64                 {
  65                         if (compare_subnode(level, op, val->length, cmpptr, (val->flag & LVAR_ANYEND)))
  66                                 return true;
  67                 }
  68                 else if (
  69                                  (
  70                                   val->length == level->len ||
  71                                   (level->len > val->length && (val->flag & LVAR_ANYEND))
  72                                   ) &&
  73                                  (*cmpptr) (op, level->name, val->length) == 0)
  74                         return true;
  75
  76                 tlen--;
  77                 level = LEVEL_NEXT(level);
  78         }
  79
  80         return false;
  81 }
  82
  83 Datum
  84 ltxtq_exec(PG_FUNCTION_ARGS)
  85 {
  86         ltree      *val = PG_GETARG_LTREE(0);
  87         ltxtquery  *query = PG_GETARG_LTXTQUERY(1);
  88         CHKVAL          chkval;
  89         bool            result;
  90
  91         chkval.node = val;
  92         chkval.operand = GETOPERAND(query);
  93
  94         result = ltree_execute(
  95                                                    GETQUERY(query),
  96                                                    &chkval,
  97                                                    true,
  98                                                    checkcondition_str
  99                 );
 100
 101         PG_FREE_IF_COPY(val, 0);
 102         PG_FREE_IF_COPY(query, 1);
 103         PG_RETURN_BOOL(result);
 104 }
 105
 106 Datum
 107 ltxtq_rexec(PG_FUNCTION_ARGS)
 108 {
 109         PG_RETURN_DATUM(DirectFunctionCall2(ltxtq_exec,
 110                                                                                 PG_GETARG_DATUM(1),
 111                                                                                 PG_GETARG_DATUM(0)
 112                                                                                 ));
 113 }