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 1.17 2007-03-19 14:40:07 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_destroy(p->wr_error);
  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             continue;
 171         if (strcmp((const char *) ptr->name, "backend")){
 172             wrbuf_printf(p->wr_error, "Element <retrieval>: expected"
 173                          " zero or one element <backend>, got <%s>",
 174                          (const char *) ptr->name);
 175             return -1;
 176         }
 177
 178         else {
 179
 180             /* parsing attributees */
 181             struct _xmlAttr *attr;
 182             for (attr = ptr->properties; attr; attr = attr->next){
 183
 184                 if (!xmlStrcmp(attr->name, BAD_CAST "name")
 185                          && attr->children
 186                          && attr->children->type == XML_TEXT_NODE)
 187                     el->backend_name
 188                         = nmem_strdup(p->nmem,
 189                                       (const char *) attr->children->content);
 190
 191                 else if (!xmlStrcmp(attr->name, BAD_CAST "syntax")
 192                          && attr->children
 193                          && attr->children->type == XML_TEXT_NODE){
 194                     el->backend_syntax
 195                     = yaz_str_to_z3950oid(p->odr, CLASS_RECSYN,
 196                        (const char *) attr->children->content);
 197
 198                     if (!el->backend_syntax){
 199                         wrbuf_printf(p->wr_error,
 200                                      "Element <backend syntax='%s'>: "
 201                                      "attribute 'syntax' has invalid "
 202                                      "value '%s'",
 203                                      attr->children->content,
 204                                      attr->children->content);
 205                         return -1;
 206                     }
 207                 }
 208                 else {
 209                     wrbuf_printf(p->wr_error, "Element <backend>: expected "
 210                                  "attributes 'syntax' or 'name, got '%s'",
 211                                  attr->name);
 212                     return -1;
 213                 }
 214             }
 215
 216
 217             /* parsing internal of record conv */
 218             el->record_conv = yaz_record_conv_create();
 219
 220             yaz_record_conv_set_path(el->record_conv, p->path);
 221
 222
 223             if (yaz_record_conv_configure(el->record_conv, ptr))
 224             {
 225                 wrbuf_printf(p->wr_error, "%s",
 226                              yaz_record_conv_get_error(el->record_conv));
 227                 yaz_record_conv_destroy(el->record_conv);
 228                 return -1;
 229             }
 230         }
 231     }
 232
 233     *p->list_p = el;
 234     p->list_p = &el->next;
 235     return 0;
 236 }
 237
 238 int yaz_retrieval_configure(yaz_retrieval_t p, const xmlNode *ptr)
 239 {
 240     yaz_retrieval_reset(p);
 241
 242     if (ptr && ptr->type == XML_ELEMENT_NODE &&
 243         !strcmp((const char *) ptr->name, "retrievalinfo"))
 244     {
 245         for (ptr = ptr->children; ptr; ptr = ptr->next)
 246         {
 247             if (ptr->type != XML_ELEMENT_NODE)
 248                 continue;
 249             if (!strcmp((const char *) ptr->name, "retrieval"))
 250             {
 251                 if (conf_retrieval(p, ptr))
 252                     return -1;
 253             }
 254             else
 255             {
 256                 wrbuf_printf(p->wr_error, "Element <retrievalinfo>: "
 257                              "expected element <retrieval>, got <%s>",
 258                              ptr->name);
 259                 return -1;
 260             }
 261         }
 262     }
 263     else
 264     {
 265         wrbuf_printf(p->wr_error, "Expected element <retrievalinfo>");
 266         return -1;
 267     }
 268     return 0;
 269 }
 270
 271 int yaz_retrieval_request(yaz_retrieval_t p,
 272                           const char *schema, int *syntax,
 273                           const char **match_schema, int **match_syntax,
 274                           yaz_record_conv_t *rc,
 275                           const char **backend_schema,
 276                           int **backend_syntax)
 277 {
 278     struct yaz_retrieval_elem *el = p->list;
 279     int syntax_matches = 0;
 280     int schema_matches = 0;
 281
 282     wrbuf_rewind(p->wr_error);
 283     if (!el)
 284         return 0;
 285     for(; el; el = el->next)
 286     {
 287         int schema_ok = 0;
 288         int syntax_ok = 0;
 289
 290         if (!schema)
 291             schema_ok = 1;
 292         else
 293         {
 294             if (el->name && !strcmp(schema, el->name))
 295                 schema_ok = 1;
 296             if (el->identifier && !strcmp(schema, el->identifier))
 297                 schema_ok = 1;
 298             if (!el->name && !el->identifier)
 299                 schema_ok = 1;
 300         }
 301
 302         if (syntax && el->syntax && !oid_oidcmp(syntax, el->syntax))
 303             syntax_ok = 1;
 304         if (!syntax)
 305             syntax_ok = 1;
 306
 307         if (syntax_ok)
 308             syntax_matches++;
 309         if (schema_ok)
 310             schema_matches++;
 311         if (syntax_ok && schema_ok)
 312         {
 313             *match_syntax = el->syntax;
 314             if (el->identifier)
 315                 *match_schema = el->identifier;
 316             else
 317                 *match_schema = 0;
 318             if (backend_schema)
 319             {
 320                 if (el->backend_name)
 321                     *backend_schema = el->backend_name;
 322                 else if (el->name)
 323                     *backend_schema = el->name;
 324                 else
 325                     *backend_schema = schema;
 326             }
 327             if (backend_syntax)
 328             {
 329                 if (el->backend_syntax)
 330                     *backend_syntax = el->backend_syntax;
 331                 else
 332                     *backend_syntax = el->syntax;
 333             }
 334             if (rc)
 335                 *rc = el->record_conv;
 336             return 0;
 337         }
 338     }
 339     if (!syntax_matches && syntax)
 340     {
 341         char buf[OID_STR_MAX];
 342         wrbuf_printf(p->wr_error, "%s", oid_to_dotstring(syntax, buf));
 343         return 2;
 344     }
 345     if (schema)
 346         wrbuf_printf(p->wr_error, "%s", schema);
 347     if (!schema_matches)
 348         return 1;
 349     return 3;
 350 }
 351
 352 const char *yaz_retrieval_get_error(yaz_retrieval_t p)
 353 {
 354     return wrbuf_cstr(p->wr_error);
 355 }
 356
 357 void yaz_retrieval_set_path(yaz_retrieval_t p, const char *path)
 358 {
 359     xfree(p->path);
 360     p->path = 0;
 361     if (path)
 362         p->path = xstrdup(path);
 363 }
 364
 365 #endif
 366
 367 /*
 368  * Local variables:
 369  * c-basic-offset: 4
 370  * indent-tabs-mode: nil
 371  * End:
 372  * vim: shiftwidth=4 tabstop=8 expandtab
 373  */
 374