src/rpn2cql.c

   1 /* This file is part of the YAZ toolkit.
   2  * Copyright (C) 1995-2008 Index Data
   3  * See the file LICENSE for details.
   4  */
   5
   6 /**
   7  * \file
   8  * \brief Implements RPN to CQL conversion
   9  *
  10  * Evaluation order of rules:
  11  *
  12  * always
  13  * relation
  14  * structure
  15  * position
  16  * truncation
  17  * index
  18  * relationModifier
  19  */
  20
  21 #include <assert.h>
  22 #include <stdlib.h>
  23 #include <string.h>
  24 #include <yaz/rpn2cql.h>
  25 #include <yaz/xmalloc.h>
  26 #include <yaz/diagbib1.h>
  27 #include <yaz/z-core.h>
  28 #include <yaz/wrbuf.h>
  29
  30 static int rpn2cql_attr(cql_transform_t ct,
  31                         void (*pr)(const char *buf, void *client_data),
  32                         void *client_data,
  33                         Z_AttributeList *attributes, WRBUF w)
  34 {
  35     int i;
  36     for (i = 0; i < attributes->num_attributes; i++)
  37     {
  38         Z_AttributeElement *elem = attributes->attributes[i];
  39     }
  40     return 0;
  41 }
  42
  43 static int rpn2cql_simple(cql_transform_t ct,
  44                           void (*pr)(const char *buf, void *client_data),
  45                           void *client_data,
  46                           Z_Operand *q, WRBUF w)
  47 {
  48     int ret = 0;
  49     if (q->which != Z_Operand_APT)
  50     {
  51         ret = -1;
  52         cql_transform_set_error(ct, YAZ_BIB1_RESULT_SET_UNSUPP_AS_A_SEARCH_TERM, 0);
  53     }
  54     else
  55     {
  56         Z_AttributesPlusTerm *apt = q->u.attributesPlusTerm;
  57         Z_Term *term = apt->term;
  58
  59         wrbuf_rewind(w);
  60         ret = rpn2cql_attr(ct, pr, client_data, apt->attributes, w);
  61
  62         switch(term->which)
  63         {
  64         case Z_Term_general:
  65             wrbuf_write(w, (const char *) term->u.general->buf, term->u.general->len);
  66             break;
  67         case Z_Term_numeric:
  68             wrbuf_printf(w, "%d", *term->u.numeric);
  69             break;
  70         case Z_Term_characterString:
  71             wrbuf_puts(w, term->u.characterString);
  72             break;
  73         default:
  74             ret = -1;
  75             cql_transform_set_error(ct, YAZ_BIB1_TERM_TYPE_UNSUPP, 0);
  76         }
  77         if (ret == 0)
  78             pr(wrbuf_cstr(w), client_data);
  79     }
  80     return ret;
  81 }
  82
  83 static int rpn2cql_structure(cql_transform_t ct,
  84                              void (*pr)(const char *buf, void *client_data),
  85                              void *client_data,
  86                              Z_RPNStructure *q, int nested,
  87                              WRBUF w)
  88 {
  89     if (q->which == Z_RPNStructure_simple)
  90         return rpn2cql_simple(ct, pr, client_data, q->u.simple, w);
  91     else
  92     {
  93         Z_Operator *op = q->u.complex->roperator;
  94         int r;
  95
  96         if (nested)
  97             pr("(", client_data);
  98
  99         r = rpn2cql_structure(ct, pr, client_data, q->u.complex->s1, 1, w);
 100         if (r)
 101             return r;
 102         switch(op->which)
 103         {
 104         case  Z_Operator_and:
 105             pr(" and ", client_data);
 106             break;
 107         case  Z_Operator_or:
 108             pr(" or ", client_data);
 109             break;
 110         case  Z_Operator_and_not:
 111             pr(" not ", client_data);
 112             break;
 113         case  Z_Operator_prox:
 114             cql_transform_set_error(ct, YAZ_BIB1_UNSUPP_SEARCH, 0);
 115             return -1;
 116         }
 117         r = rpn2cql_structure(ct, pr, client_data, q->u.complex->s2, 1, w);
 118         if (nested)
 119             pr(")", client_data);
 120         return r;
 121     }
 122 }
 123
 124 int cql_transform_rpn2cql_stream(cql_transform_t ct,
 125                                  void (*pr)(const char *buf, void *client_data),
 126                                  void *client_data,
 127                                  Z_RPNQuery *q)
 128 {
 129     int r;
 130     WRBUF w = wrbuf_alloc();
 131     cql_transform_set_error(ct, 0, 0);
 132     r = rpn2cql_structure(ct, pr, client_data, q->RPNStructure, 0, w);
 133     wrbuf_destroy(w);
 134     return r;
 135 }
 136
 137
 138 int cql_transform_rpn2cql_wrbuf(cql_transform_t ct,
 139                                 WRBUF w,
 140                                 Z_RPNQuery *q)
 141 {
 142     return cql_transform_rpn2cql_stream(ct, wrbuf_vputs, w, q);
 143 }
 144
 145 /*
 146  * Local variables:
 147  * c-basic-offset: 4
 148  * indent-tabs-mode: nil
 149  * End:
 150  * vim: shiftwidth=4 tabstop=8 expandtab
 151  */
 152