src/retrieval.c

   1 /*
   2  * Copyright (C) 2005-2007, Index Data ApS
   3  * See the file LICENSE for details.
   4  *
   5  * $Id: retrieval.c,v 1.15 2007-01-03 08:42:15 adam Exp $
   6  */
   7 /**
   8  * \file retrieval.c
   9  * \brief Retrieval utility
  10  */
  11
  12 #if HAVE_CONFIG_H
  13 #include <config.h>
  14 #endif
  15
  16 #include <string.h>
  17 #include <yaz/retrieval.h>
  18 #include <yaz/wrbuf.h>
  19 #include <yaz/xmalloc.h>
  20 #include <yaz/nmem.h>
  21 #include <yaz/tpath.h>
  22 #include <yaz/proto.h>
  23
  24 #if YAZ_HAVE_XML2
  25 #include <libxml/parser.h>
  26 #include <libxml/tree.h>
  27 #include <libxml/xinclude.h>
  28
  29 /** \brief The internal structure for yaz_retrieval_t */
  30 struct yaz_retrieval_struct {
  31     /** \brief ODR memory for configuration */
  32     ODR odr;
  33
  34     /** \brief odr's NMEM memory (odr->mem) */
  35     NMEM nmem;
  36
  37     /** \brief string buffer for error messages */
  38     WRBUF wr_error;
  39
  40     /** \brief path for opening files  */
  41     char *path;
  42
  43     /** \brief retrieval list */
  44     struct yaz_retrieval_elem *list;
  45
  46     /** \brief last pointer in retrieval list */
  47     struct yaz_retrieval_elem **list_p;
  48 };
  49
  50 /** \brief information per 'retrieval' construct */
  51 struct yaz_retrieval_elem {
  52     /** \brief schema identifier */
  53     const char *identifier;
  54     /** \brief schema name , short-hand such as "dc" */
  55     const char *name;
  56     /** \brief record syntax */
  57     int *syntax;
  58
  59     /** \brief backend name */
  60     const char *backend_name;
  61     /** \brief backend syntax */
  62     int *backend_syntax;
  63
  64     /** \brief record conversion */
  65     yaz_record_conv_t record_conv;
  66
  67     /** \brief next element in list */
  68     struct yaz_retrieval_elem *next;
  69 };
  70
  71 static void yaz_retrieval_reset(yaz_retrieval_t p);
  72
  73 yaz_retrieval_t yaz_retrieval_create()
  74 {
  75     yaz_retrieval_t p = xmalloc(sizeof(*p));
  76     p->odr = odr_createmem(ODR_ENCODE);
  77     p->nmem = p->odr->mem;
  78     p->wr_error = wrbuf_alloc();
  79     p->list = 0;
  80     p->path = 0;
  81     yaz_retrieval_reset(p);
  82     return p;
  83 }
  84
  85 void yaz_retrieval_destroy(yaz_retrieval_t p)
  86 {
  87     if (p)
  88     {
  89         yaz_retrieval_reset(p);
  90         odr_destroy(p->odr);
  91         wrbuf_free(p->wr_error, 1);
  92         xfree(p->path);
  93         xfree(p);
  94     }
  95 }
  96
  97 void yaz_retrieval_reset(yaz_retrieval_t p)
  98 {
  99     struct yaz_retrieval_elem *el = p->list;
 100     for(; el; el = el->next)
 101         yaz_record_conv_destroy(el->record_conv);
 102
 103     wrbuf_rewind(p->wr_error);
 104     odr_reset(p->odr);
 105
 106     p->list = 0;
 107     p->list_p = &p->list;
 108 }
 109
 110 /** \brief parse retrieval XML config */
 111 static int conf_retrieval(yaz_retrieval_t p, const xmlNode *ptr)
 112 {
 113
 114     struct _xmlAttr *attr;
 115     struct yaz_retrieval_elem *el = nmem_malloc(p->nmem, sizeof(*el));
 116
 117     el->syntax = 0;
 118     el->identifier = 0;
 119     el->name = 0;
 120     el->backend_name = 0;
 121     el->backend_syntax = 0;
 122
 123     el->next = 0;
 124
 125     for (attr = ptr->properties; attr; attr = attr->next)
 126     {
 127         if (!xmlStrcmp(attr->name, BAD_CAST "syntax") &&
 128             attr->children && attr->children->type == XML_TEXT_NODE)
 129         {
 130             el->syntax = yaz_str_to_z3950oid(
 131                 p->odr, CLASS_RECSYN,
 132                 (const char *) attr->children->content);
 133             if (!el->syntax)
 134             {
 135                 wrbuf_printf(p->wr_error, "Element <retrieval>: "
 136                              " unknown attribute value syntax='%s'",
 137                              (const char *) attr->children->content);
 138                 return -1;
 139             }
 140         }
 141         else if (!xmlStrcmp(attr->name, BAD_CAST "identifier") &&
 142                  attr->children && attr->children->type == XML_TEXT_NODE)
 143             el->identifier =
 144                 nmem_strdup(p->nmem, (const char *) attr->children->content);
 145         else if (!xmlStrcmp(attr->name, BAD_CAST "name") &&
 146                  attr->children && attr->children->type == XML_TEXT_NODE)
 147             el->name =
 148                 nmem_strdup(p->nmem, (const char *) attr->children->content);
 149         else
 150         {
 151             wrbuf_printf(p->wr_error, "Element <retrieval>: "
 152                          " expected attributes 'syntax', identifier' or "
 153                          "'name', got '%s'", attr->name);
 154             return -1;
 155         }
 156     }
 157
 158     if (!el->syntax)
 159     {
 160         wrbuf_printf(p->wr_error, "Missing 'syntax' attribute");
 161         return -1;
 162     }
 163
 164     /* parsing backend element */
 165
 166     el->record_conv = 0; /* OK to have no 'backend' sub content */
 167     for (ptr = ptr->children; ptr; ptr = ptr->next)
 168     {
 169         if (ptr->type == XML_ELEMENT_NODE
 170             && 0 != strcmp((const char *) ptr->name, "backend")){
 171             wrbuf_printf(p->wr_error, "Element <retrieval>: expected"
 172                          " zero or one element <backend>, got <%s>",
 173                          (const char *) ptr->name);
 174             return -1;
 175         }
 176
 177         else {
 178
 179             /* parsing attributees */
 180             struct _xmlAttr *attr;
 181             for (attr = ptr->properties; attr; attr = attr->next){
 182
 183                 if (!xmlStrcmp(attr->name, BAD_CAST "name")
 184                          && attr->children
 185                          && attr->children->type == XML_TEXT_NODE)
 186                     el->backend_name
 187                         = nmem_strdup(p->nmem,
 188                                       (const char *) attr->children->content);
 189
 190                 else if (!xmlStrcmp(attr->name, BAD_CAST "syntax")
 191                          && attr->children
 192                          && attr->children->type == XML_TEXT_NODE){
 193                     el->backend_syntax
 194                     = yaz_str_to_z3950oid(p->odr, CLASS_RECSYN,
 195                        (const char *) attr->children->content);
 196
 197                     if (!el->backend_syntax){
 198                         wrbuf_printf(p->wr_error,
 199                                      "Element <backend syntax='%s'>: "
 200                                      "attribute 'syntax' has invalid "
 201                                      "value '%s'",
 202                                      attr->children->content,
 203                                      attr->children->content);
 204                         return -1;
 205                     }
 206                 }
 207                 else {
 208                     wrbuf_printf(p->wr_error, "Element <backend>: expected "
 209                                  "attributes 'syntax' or 'name, got '%s'",
 210                                  attr->name);
 211                     return -1;
 212                 }
 213             }
 214
 215
 216             /* parsing internal of record conv */
 217             el->record_conv = yaz_record_conv_create();
 218
 219             yaz_record_conv_set_path(el->record_conv, p->path);
 220
 221
 222             if (yaz_record_conv_configure(el->record_conv, ptr))
 223             {
 224                 wrbuf_printf(p->wr_error, "%s",
 225                              yaz_record_conv_get_error(el->record_conv));
 226                 yaz_record_conv_destroy(el->record_conv);
 227                 return -1;
 228             }
 229         }
 230     }
 231
 232     *p->list_p = el;
 233     p->list_p = &el->next;
 234     return 0;
 235 }
 236
 237 int yaz_retrieval_configure(yaz_retrieval_t p, const xmlNode *ptr)
 238 {
 239     yaz_retrieval_reset(p);
 240
 241     if (ptr && ptr->type == XML_ELEMENT_NODE &&
 242         !strcmp((const char *) ptr->name, "retrievalinfo"))
 243     {
 244         for (ptr = ptr->children; ptr; ptr = ptr->next)
 245         {
 246             if (ptr->type != XML_ELEMENT_NODE)
 247                 continue;
 248             if (!strcmp((const char *) ptr->name, "retrieval"))
 249             {
 250                 if (conf_retrieval(p, ptr))
 251                     return -1;
 252             }
 253             else
 254             {
 255                 wrbuf_printf(p->wr_error, "Element <retrievalinfo>: "
 256                              "expected element <retrieval>, got <%s>",
 257                              ptr->name);
 258                 return -1;
 259             }
 260         }
 261     }
 262     else
 263     {
 264         wrbuf_printf(p->wr_error, "Expected element <retrievalinfo>");
 265         return -1;
 266     }
 267     return 0;
 268 }
 269
 270 int yaz_retrieval_request(yaz_retrieval_t p,
 271                           const char *schema, int *syntax,
 272                           const char **match_schema, int **match_syntax,
 273                           yaz_record_conv_t *rc,
 274                           const char **backend_schema,
 275                           int **backend_syntax)
 276 {
 277     struct yaz_retrieval_elem *el = p->list;
 278     int syntax_matches = 0;
 279     int schema_matches = 0;
 280
 281     wrbuf_rewind(p->wr_error);
 282     if (!el)
 283         return 0;
 284     for(; el; el = el->next)
 285     {
 286         int schema_ok = 0;
 287         int syntax_ok = 0;
 288
 289         if (!schema)
 290             schema_ok = 1;
 291         else
 292         {
 293             if (el->name && !strcmp(schema, el->name))
 294                 schema_ok = 1;
 295             if (el->identifier && !strcmp(schema, el->identifier))
 296                 schema_ok = 1;
 297             if (!el->name && !el->identifier)
 298                 schema_ok = 1;
 299         }
 300
 301         if (syntax && el->syntax && !oid_oidcmp(syntax, el->syntax))
 302             syntax_ok = 1;
 303         if (!syntax)
 304             syntax_ok = 1;
 305
 306         if (syntax_ok)
 307             syntax_matches++;
 308         if (schema_ok)
 309             schema_matches++;
 310         if (syntax_ok && schema_ok)
 311         {
 312             *match_syntax = el->syntax;
 313             if (el->identifier)
 314                 *match_schema = el->identifier;
 315             else
 316                 *match_schema = 0;
 317             if (backend_schema)
 318             {
 319                 if (el->backend_name)
 320                     *backend_schema = el->backend_name;
 321                 else if (el->name)
 322                     *backend_schema = el->name;
 323                 else
 324                     *backend_schema = schema;
 325             }
 326             if (backend_syntax)
 327             {
 328                 if (el->backend_syntax)
 329                     *backend_syntax = el->backend_syntax;
 330                 else
 331                     *backend_syntax = el->syntax;
 332             }
 333             if (rc)
 334                 *rc = el->record_conv;
 335             return 0;
 336         }
 337     }
 338     if (!syntax_matches && syntax)
 339     {
 340         char buf[OID_STR_MAX];
 341         wrbuf_printf(p->wr_error, "%s", oid_to_dotstring(syntax, buf));
 342         return 2;
 343     }
 344     if (schema)
 345         wrbuf_printf(p->wr_error, "%s", schema);
 346     if (!schema_matches)
 347         return 1;
 348     return 3;
 349 }
 350
 351 const char *yaz_retrieval_get_error(yaz_retrieval_t p)
 352 {
 353     return wrbuf_buf(p->wr_error);
 354 }
 355
 356 void yaz_retrieval_set_path(yaz_retrieval_t p, const char *path)
 357 {
 358     xfree(p->path);
 359     p->path = 0;
 360     if (path)
 361         p->path = xstrdup(path);
 362 }
 363
 364 #endif
 365
 366 /*
 367  * Local variables:
 368  * c-basic-offset: 4
 369  * indent-tabs-mode: nil
 370  * End:
 371  * vim: shiftwidth=4 tabstop=8 expandtab
 372  */
 373