recctrl/xslt.c

   1 /* $Id: xslt.c,v 1.27 2006-05-31 16:11:58 marc Exp $
   2    Copyright (C) 1995-2005
   3    Index Data ApS
   4
   5 This file is part of the Zebra server.
   6
   7 Zebra is free software; you can redistribute it and/or modify it under
   8 the terms of the GNU General Public License as published by the Free
   9 Software Foundation; either version 2, or (at your option) any later
  10 version.
  11
  12 Zebra is distributed in the hope that it will be useful, but WITHOUT ANY
  13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  15 for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with Zebra; see the file LICENSE.zebra.  If not, write to the
  19 Free Software Foundation, 59 Temple Place - Suite 330, Boston, MA
  20 02111-1307, USA.
  21 */
  22
  23 #include <stdio.h>
  24 #include <assert.h>
  25 #include <ctype.h>
  26
  27 #include <yaz/diagbib1.h>
  28 #include <yaz/tpath.h>
  29
  30 #include <libxml/xmlversion.h>
  31 #include <libxml/parser.h>
  32 #include <libxml/tree.h>
  33 #include <libxml/xmlIO.h>
  34 #include <libxml/xmlreader.h>
  35 #include <libxslt/transform.h>
  36 /* #include <libxslt/xsltutils.h> */
  37
  38 #include <idzebra/util.h>
  39 #include <idzebra/recctrl.h>
  40
  41 struct filter_xslt_schema {
  42     const char *name;
  43     const char *identifier;
  44     const char *stylesheet;
  45     struct filter_xslt_schema *next;
  46     const char *default_schema;
  47     const char *include_snippet;
  48     xsltStylesheetPtr stylesheet_xsp;
  49 };
  50
  51 struct filter_xslt_info {
  52     xmlDocPtr doc;
  53     char *fname;
  54     char *full_name;
  55     const char *profile_path;
  56     const char *split_level;
  57     const char *split_path;
  58     ODR odr;
  59     struct filter_xslt_schema *schemas;
  60     xmlTextReaderPtr reader;
  61 };
  62
  63
  64 #define ZEBRA_SCHEMA_XSLT_NS "http://indexdata.dk/zebra/xslt/1"
  65
  66 #define XML_STRCMP(a,b)   strcmp((char*)a, b)
  67 #define XML_STRLEN(a) strlen((char*)a)
  68
  69 static const char *zebra_xslt_ns = ZEBRA_SCHEMA_XSLT_NS;
  70
  71 static void set_param_xml(const char **params, const char *name,
  72                           const char *value, ODR odr)
  73 {
  74     while (*params)
  75         params++;
  76     params[0] = name;
  77     params[1] = value;
  78     params[2] = 0;
  79 }
  80
  81 static void set_param_str(const char **params, const char *name,
  82                           const char *value, ODR odr)
  83 {
  84     char *quoted = odr_malloc(odr, 3 + strlen(value));
  85     sprintf(quoted, "'%s'", value);
  86     while (*params)
  87         params++;
  88     params[0] = name;
  89     params[1] = quoted;
  90     params[2] = 0;
  91 }
  92
  93 static void set_param_int(const char **params, const char *name,
  94                           zint value, ODR odr)
  95 {
  96     char *quoted = odr_malloc(odr, 30); /* 25 digits enough for 2^64 */
  97     while (*params)
  98         params++;
  99     sprintf(quoted, "'" ZINT_FORMAT "'", value);
 100     params[0] = name;
 101     params[1] = quoted;
 102     params[2] = 0;
 103 }
 104
 105 #define ENABLE_INPUT_CALLBACK 0
 106
 107 #if ENABLE_INPUT_CALLBACK
 108 static int zebra_xmlInputMatchCallback (char const *filename)
 109 {
 110     yaz_log(YLOG_LOG, "match %s", filename);
 111     return 0;
 112 }
 113
 114 static void * zebra_xmlInputOpenCallback (char const *filename)
 115 {
 116     return 0;
 117 }
 118
 119 static int zebra_xmlInputReadCallback (void * context, char * buffer, int len)
 120 {
 121     return 0;
 122 }
 123
 124 static int zebra_xmlInputCloseCallback (void * context)
 125 {
 126     return 0;
 127 }
 128 #endif
 129
 130 static void *filter_init(Res res, RecType recType)
 131 {
 132     struct filter_xslt_info *tinfo
 133       = (struct filter_xslt_info *) xmalloc(sizeof(*tinfo));
 134     tinfo->reader = 0;
 135     tinfo->fname = 0;
 136     tinfo->full_name = 0;
 137     tinfo->profile_path = 0;
 138     tinfo->split_level = 0;
 139     tinfo->split_path = 0;
 140     tinfo->odr = odr_createmem(ODR_ENCODE);
 141     tinfo->doc = 0;
 142     tinfo->schemas = 0;
 143
 144 #if ENABLE_INPUT_CALLBACK
 145     xmlRegisterDefaultInputCallbacks();
 146     xmlRegisterInputCallbacks(zebra_xmlInputMatchCallback,
 147                               zebra_xmlInputOpenCallback,
 148                               zebra_xmlInputReadCallback,
 149                               zebra_xmlInputCloseCallback);
 150 #endif
 151     return tinfo;
 152 }
 153
 154 static int attr_content(struct _xmlAttr *attr, const char *name,
 155                         const char **dst_content)
 156 {
 157     if (!XML_STRCMP(attr->name, name) && attr->children &&
 158         attr->children->type == XML_TEXT_NODE)
 159     {
 160         *dst_content = (const char *)(attr->children->content);
 161         return 1;
 162     }
 163     return 0;
 164 }
 165
 166 static void destroy_schemas(struct filter_xslt_info *tinfo)
 167 {
 168     struct filter_xslt_schema *schema = tinfo->schemas;
 169     while (schema)
 170     {
 171         struct filter_xslt_schema *schema_next = schema->next;
 172         if (schema->stylesheet_xsp)
 173             xsltFreeStylesheet(schema->stylesheet_xsp);
 174         xfree(schema);
 175         schema = schema_next;
 176     }
 177     tinfo->schemas = 0;
 178     xfree(tinfo->fname);
 179     if (tinfo->doc)
 180         xmlFreeDoc(tinfo->doc);
 181     tinfo->doc = 0;
 182 }
 183
 184 static ZEBRA_RES create_schemas(struct filter_xslt_info *tinfo,
 185                                 const char *fname)
 186 {
 187     char tmp_full_name[1024];
 188     xmlNodePtr ptr;
 189     tinfo->fname = xstrdup(fname);
 190
 191     if (yaz_filepath_resolve(tinfo->fname, tinfo->profile_path,
 192                              NULL, tmp_full_name))
 193       tinfo->full_name = xstrdup(tmp_full_name);
 194     else
 195       tinfo->full_name = xstrdup(tinfo->fname);
 196
 197     yaz_log(YLOG_LOG, "xslt filter: loading config file %s", tinfo->full_name);
 198
 199     tinfo->doc = xmlParseFile(tinfo->full_name);
 200     if (!tinfo->doc) {
 201       yaz_log(YLOG_WARN, "xslt filter: could not parse config file %s",
 202               tinfo->full_name);
 203       return ZEBRA_FAIL;
 204     }
 205
 206     ptr = xmlDocGetRootElement(tinfo->doc);
 207     if (!ptr || ptr->type != XML_ELEMENT_NODE ||
 208         XML_STRCMP(ptr->name, "schemaInfo")){
 209           yaz_log(YLOG_WARN,
 210                   "xslt filter:  config file %s :"
 211                   " expected root element <schemaInfo>",
 212               tinfo->full_name);
 213       return ZEBRA_FAIL;
 214     }
 215
 216     for (ptr = ptr->children; ptr; ptr = ptr->next)
 217     {
 218         if (ptr->type != XML_ELEMENT_NODE)
 219             continue;
 220         if (!XML_STRCMP(ptr->name, "schema"))
 221         {
 222             char tmp_xslt_full_name[1024];
 223             struct _xmlAttr *attr;
 224             struct filter_xslt_schema *schema = xmalloc(sizeof(*schema));
 225             schema->name = 0;
 226             schema->identifier = 0;
 227             schema->stylesheet = 0;
 228             schema->default_schema = 0;
 229             schema->next = tinfo->schemas;
 230             schema->stylesheet_xsp = 0;
 231             schema->include_snippet = 0;
 232             tinfo->schemas = schema;
 233             for (attr = ptr->properties; attr; attr = attr->next)
 234             {
 235                 attr_content(attr, "identifier", &schema->identifier);
 236                 attr_content(attr, "name", &schema->name);
 237                 attr_content(attr, "stylesheet", &schema->stylesheet);
 238                 attr_content(attr, "default", &schema->default_schema);
 239                 attr_content(attr, "snippet", &schema->include_snippet);
 240             }
 241
 242             if (schema->stylesheet){
 243               yaz_filepath_resolve(schema->stylesheet, tinfo->profile_path,
 244                                    NULL, tmp_xslt_full_name);
 245               schema->stylesheet_xsp
 246                 = xsltParseStylesheetFile((const xmlChar*) tmp_xslt_full_name);
 247               if (!schema->stylesheet_xsp)
 248                 yaz_log(YLOG_WARN,
 249                         "xslt filter: could not parse xslt stylesheet %s",
 250                         tmp_xslt_full_name);
 251             }
 252
 253         }
 254         else if (!XML_STRCMP(ptr->name, "split"))
 255         {
 256             struct _xmlAttr *attr;
 257             for (attr = ptr->properties; attr; attr = attr->next)
 258             {
 259                 attr_content(attr, "level", &tinfo->split_level);
 260                 attr_content(attr, "path", &tinfo->split_path);
 261             }
 262         }
 263         else
 264         {
 265             yaz_log(YLOG_WARN, "Bad element %s in %s", ptr->name, fname);
 266             return ZEBRA_FAIL;
 267         }
 268     }
 269     return ZEBRA_OK;
 270 }
 271
 272 static struct filter_xslt_schema *lookup_schema(struct filter_xslt_info *tinfo,
 273                                            const char *est)
 274 {
 275     struct filter_xslt_schema *schema;
 276     for (schema = tinfo->schemas; schema; schema = schema->next)
 277     {
 278         /* find requested schema */
 279         if (est)
 280         {
 281             if (schema->identifier && !strcmp(schema->identifier, est))
 282                 return schema;
 283
 284             if (schema->name && !strcmp(schema->name, est))
 285                 return schema;
 286         }
 287         /* or return default schema if defined */
 288         else if (schema->default_schema)
 289             return schema;
 290     }
 291
 292     /* return first schema if no default schema defined */
 293     if (tinfo->schemas)
 294         return tinfo->schemas;
 295
 296     return 0;
 297 }
 298
 299 static ZEBRA_RES filter_config(void *clientData, Res res, const char *args)
 300 {
 301     struct filter_xslt_info *tinfo = clientData;
 302     if (!args || !*args){
 303       yaz_log(YLOG_WARN, "xslt filter: need config file");
 304       return ZEBRA_FAIL;
 305     }
 306
 307     if (tinfo->fname && !strcmp(args, tinfo->fname))
 308         return ZEBRA_OK;
 309
 310     tinfo->profile_path
 311       /* = res_get_def(res, "profilePath", DEFAULT_PROFILE_PATH); */
 312       = res_get(res, "profilePath");
 313     yaz_log(YLOG_LOG, "xslt filter: profilePath %s", tinfo->profile_path);
 314
 315     destroy_schemas(tinfo);
 316     create_schemas(tinfo, args);
 317     return ZEBRA_OK;
 318 }
 319
 320 static void filter_destroy(void *clientData)
 321 {
 322     struct filter_xslt_info *tinfo = clientData;
 323     destroy_schemas(tinfo);
 324     if (tinfo->reader)
 325         xmlFreeTextReader(tinfo->reader);
 326     odr_destroy(tinfo->odr);
 327     xfree(tinfo);
 328 }
 329
 330 static int ioread_ex(void *context, char *buffer, int len)
 331 {
 332     struct recExtractCtrl *p = context;
 333     return (*p->readf)(p->fh, buffer, len);
 334 }
 335
 336 static int ioclose_ex(void *context)
 337 {
 338     return 0;
 339 }
 340
 341 static void index_cdata(struct filter_xslt_info *tinfo, struct recExtractCtrl *ctrl,
 342                         xmlNodePtr ptr, RecWord *recWord)
 343 {
 344     for(; ptr; ptr = ptr->next)
 345     {
 346         index_cdata(tinfo, ctrl, ptr->children, recWord);
 347         if (ptr->type != XML_TEXT_NODE)
 348             continue;
 349         recWord->term_buf = (const char *)ptr->content;
 350         recWord->term_len = XML_STRLEN(ptr->content);
 351         (*ctrl->tokenAdd)(recWord);
 352     }
 353 }
 354
 355 static void index_node(struct filter_xslt_info *tinfo,  struct recExtractCtrl *ctrl,
 356                        xmlNodePtr ptr, RecWord *recWord)
 357 {
 358     for(; ptr; ptr = ptr->next)
 359     {
 360         index_node(tinfo, ctrl, ptr->children, recWord);
 361         if (ptr->type != XML_ELEMENT_NODE || !ptr->ns ||
 362             XML_STRCMP(ptr->ns->href, zebra_xslt_ns))
 363             continue;
 364         if (!XML_STRCMP(ptr->name, "index"))
 365         {
 366             const char *name_str = 0;
 367             const char *type_str = 0;
 368             const char *xpath_str = 0;
 369             struct _xmlAttr *attr;
 370             for (attr = ptr->properties; attr; attr = attr->next)
 371             {
 372                 attr_content(attr, "name", &name_str);
 373                 attr_content(attr, "xpath", &xpath_str);
 374                 attr_content(attr, "type", &type_str);
 375             }
 376             if (name_str)
 377             {
 378                 int prev_type = recWord->index_type; /* save default type */
 379
 380                 if (type_str && *type_str)
 381                     recWord->index_type = *type_str; /* type was given */
 382                 recWord->index_name = name_str;
 383                 index_cdata(tinfo, ctrl, ptr->children, recWord);
 384
 385                 recWord->index_type = prev_type;     /* restore it again */
 386             }
 387         }
 388     }
 389 }
 390
 391 static void index_record(struct filter_xslt_info *tinfo,struct recExtractCtrl *ctrl,
 392                          xmlNodePtr ptr, RecWord *recWord)
 393 {
 394     if (ptr && ptr->type == XML_ELEMENT_NODE && ptr->ns &&
 395         !XML_STRCMP(ptr->ns->href, zebra_xslt_ns)
 396         && !XML_STRCMP(ptr->name, "record"))
 397     {
 398         const char *type_str = "update";
 399         const char *id_str = 0;
 400         const char *rank_str = 0;
 401         struct _xmlAttr *attr;
 402         for (attr = ptr->properties; attr; attr = attr->next)
 403         {
 404             attr_content(attr, "type", &type_str);
 405             attr_content(attr, "id", &id_str);
 406             attr_content(attr, "rank", &rank_str);
 407         }
 408         if (id_str)
 409             sscanf(id_str, "%255s", ctrl->match_criteria);
 410         if (rank_str)
 411         {
 412             ctrl->staticrank = atoi(rank_str);
 413             yaz_log(YLOG_LOG, "rank=%d",ctrl->staticrank);
 414         }
 415         else
 416             yaz_log(YLOG_LOG, "no rank");
 417
 418         ptr = ptr->children;
 419     }
 420     index_node(tinfo, ctrl, ptr, recWord);
 421 }
 422
 423 static int extract_doc(struct filter_xslt_info *tinfo, struct recExtractCtrl *p,
 424                        xmlDocPtr doc)
 425 {
 426     RecWord recWord;
 427     const char *params[10];
 428     xmlChar *buf_out;
 429     int len_out;
 430
 431     struct filter_xslt_schema *schema = lookup_schema(tinfo, zebra_xslt_ns);
 432
 433     params[0] = 0;
 434     set_param_str(params, "schema", zebra_xslt_ns, tinfo->odr);
 435
 436     (*p->init)(p, &recWord);
 437
 438     if (schema && schema->stylesheet_xsp)
 439     {
 440         xmlNodePtr root_ptr;
 441         xmlDocPtr resDoc =
 442             xsltApplyStylesheet(schema->stylesheet_xsp,
 443                                 doc, params);
 444         if (p->flagShowRecords)
 445         {
 446             xmlDocDumpMemory(resDoc, &buf_out, &len_out);
 447             fwrite(buf_out, len_out, 1, stdout);
 448             xmlFree(buf_out);
 449         }
 450         root_ptr = xmlDocGetRootElement(resDoc);
 451         if (root_ptr)
 452             index_record(tinfo, p, root_ptr, &recWord);
 453         else
 454         {
 455             yaz_log(YLOG_WARN, "No root for index XML record."
 456                     " split_level=%s stylesheet=%s",
 457                     tinfo->split_level, schema->stylesheet);
 458         }
 459         xmlFreeDoc(resDoc);
 460     }
 461     xmlDocDumpMemory(doc, &buf_out, &len_out);
 462     if (p->flagShowRecords)
 463         fwrite(buf_out, len_out, 1, stdout);
 464     (*p->setStoreData)(p, buf_out, len_out);
 465     xmlFree(buf_out);
 466
 467     xmlFreeDoc(doc);
 468     return RECCTRL_EXTRACT_OK;
 469 }
 470
 471 static int extract_split(struct filter_xslt_info *tinfo, struct recExtractCtrl *p)
 472 {
 473     int ret;
 474     int split_depth = 0;
 475     if (p->first_record)
 476     {
 477         if (tinfo->reader)
 478             xmlFreeTextReader(tinfo->reader);
 479         tinfo->reader = xmlReaderForIO(ioread_ex, ioclose_ex,
 480                                        p /* I/O handler */,
 481                                        0 /* URL */,
 482                                        0 /* encoding */,
 483                                        XML_PARSE_XINCLUDE);
 484     }
 485     if (!tinfo->reader)
 486         return RECCTRL_EXTRACT_ERROR_GENERIC;
 487
 488     if (tinfo->split_level)
 489         split_depth = atoi(tinfo->split_level);
 490     ret = xmlTextReaderRead(tinfo->reader);
 491     while (ret == 1) {
 492         int type = xmlTextReaderNodeType(tinfo->reader);
 493         int depth = xmlTextReaderDepth(tinfo->reader);
 494         if (split_depth == 0 ||
 495             (split_depth > 0 &&
 496              type == XML_READER_TYPE_ELEMENT && split_depth == depth))
 497         {
 498             xmlNodePtr ptr = xmlTextReaderExpand(tinfo->reader);
 499             xmlNodePtr ptr2 = xmlCopyNode(ptr, 1);
 500             xmlDocPtr doc = xmlNewDoc((const xmlChar*) "1.0");
 501
 502             xmlDocSetRootElement(doc, ptr2);
 503
 504             return extract_doc(tinfo, p, doc);
 505         }
 506         ret = xmlTextReaderRead(tinfo->reader);
 507     }
 508     xmlFreeTextReader(tinfo->reader);
 509     tinfo->reader = 0;
 510     return RECCTRL_EXTRACT_EOF;
 511 }
 512
 513 static int extract_full(struct filter_xslt_info *tinfo, struct recExtractCtrl *p)
 514 {
 515     if (p->first_record) /* only one record per stream */
 516     {
 517         xmlDocPtr doc = xmlReadIO(ioread_ex, ioclose_ex, p /* I/O handler */,
 518                                   0 /* URL */,
 519                                   0 /* encoding */,
 520                                   XML_PARSE_XINCLUDE);
 521         if (!doc)
 522         {
 523             return RECCTRL_EXTRACT_ERROR_GENERIC;
 524         }
 525         return extract_doc(tinfo, p, doc);
 526     }
 527     else
 528         return RECCTRL_EXTRACT_EOF;
 529 }
 530
 531 static int filter_extract(void *clientData, struct recExtractCtrl *p)
 532 {
 533     struct filter_xslt_info *tinfo = clientData;
 534
 535     odr_reset(tinfo->odr);
 536
 537     if (tinfo->split_level == 0 && tinfo->split_path == 0)
 538         return extract_full(tinfo, p);
 539     else
 540     {
 541         return extract_split(tinfo, p);
 542     }
 543 }
 544
 545 static int ioread_ret(void *context, char *buffer, int len)
 546 {
 547     struct recRetrieveCtrl *p = context;
 548     return (*p->readf)(p->fh, buffer, len);
 549 }
 550
 551 static int ioclose_ret(void *context)
 552 {
 553     return 0;
 554 }
 555
 556
 557 static const char *snippet_doc(struct recRetrieveCtrl *p, int text_mode,
 558                                int window_size)
 559 {
 560     const char *xml_doc_str;
 561     int ord = 0;
 562     WRBUF wrbuf = wrbuf_alloc();
 563     zebra_snippets *res =
 564         zebra_snippets_window(p->doc_snippet, p->hit_snippet, window_size);
 565     zebra_snippet_word *w = zebra_snippets_list(res);
 566
 567     if (text_mode)
 568         wrbuf_printf(wrbuf, "\'");
 569     else
 570         wrbuf_printf(wrbuf, "<snippet xmlns='%s'>\n", zebra_xslt_ns);
 571     for (; w; w = w->next)
 572     {
 573         if (ord == 0)
 574             ord = w->ord;
 575         else if (ord != w->ord)
 576
 577             break;
 578         if (text_mode)
 579             wrbuf_printf(wrbuf, "%s%s%s ",
 580                          w->match ? "*" : "",
 581                          w->term,
 582                          w->match ? "*" : "");
 583         else
 584         {
 585             wrbuf_printf(wrbuf, " <term ord='%d' seqno='" ZINT_FORMAT "' %s>",
 586                          w->ord, w->seqno,
 587                          (w->match ? "match='1'" : ""));
 588             wrbuf_xmlputs(wrbuf, w->term);
 589             wrbuf_printf(wrbuf, "</term>\n");
 590         }
 591     }
 592     if (text_mode)
 593         wrbuf_printf(wrbuf, "\'");
 594     else
 595         wrbuf_printf(wrbuf, "</snippet>\n");
 596
 597     xml_doc_str = odr_strdup(p->odr, wrbuf_buf(wrbuf));
 598
 599     zebra_snippets_destroy(res);
 600     wrbuf_free(wrbuf, 1);
 601     return xml_doc_str;
 602 }
 603
 604 static int filter_retrieve (void *clientData, struct recRetrieveCtrl *p)
 605 {
 606     const char *esn = 0;
 607     const char *params[32];
 608     struct filter_xslt_info *tinfo = clientData;
 609     xmlDocPtr resDoc;
 610     xmlDocPtr doc;
 611     struct filter_xslt_schema *schema;
 612     int window_size = -1;
 613
 614     if (p->comp)
 615     {
 616         if (p->comp->which == Z_RecordComp_simple
 617             && p->comp->u.simple->which == Z_ElementSetNames_generic)
 618         {
 619             esn = p->comp->u.simple->u.generic;
 620         }
 621         else if (p->comp->which == Z_RecordComp_complex
 622                  && p->comp->u.complex->generic->elementSpec
 623                  && p->comp->u.complex->generic->elementSpec->which ==
 624                  Z_ElementSpec_elementSetName)
 625         {
 626             esn = p->comp->u.complex->generic->elementSpec->u.elementSetName;
 627         }
 628     }
 629     schema = lookup_schema(tinfo, esn);
 630     if (!schema)
 631     {
 632         p->diagnostic =
 633             YAZ_BIB1_SPECIFIED_ELEMENT_SET_NAME_NOT_VALID_FOR_SPECIFIED_;
 634         return 0;
 635     }
 636
 637     if (schema->include_snippet)
 638         window_size = atoi(schema->include_snippet);
 639
 640     params[0] = 0;
 641     set_param_int(params, "id", p->localno, p->odr);
 642     if (p->fname)
 643         set_param_str(params, "filename", p->fname, p->odr);
 644     if (p->staticrank >= 0)
 645         set_param_int(params, "rank", p->staticrank, p->odr);
 646
 647      if (esn)
 648         set_param_str(params, "schema", esn, p->odr);
 649     else
 650         if (schema->name)
 651             set_param_str(params, "schema", schema->name, p->odr);
 652         else if (schema->identifier)
 653             set_param_str(params, "schema", schema->identifier, p->odr);
 654         else
 655             set_param_str(params, "schema", "", p->odr);
 656
 657     if (p->score >= 0)
 658         set_param_int(params, "score", p->score, p->odr);
 659     set_param_int(params, "size", p->recordSize, p->odr);
 660
 661     if (window_size >= 0)
 662         set_param_xml(params, "snippet", snippet_doc(p, 1, window_size),
 663                       p->odr);
 664     doc = xmlReadIO(ioread_ret, ioclose_ret, p /* I/O handler */,
 665                     0 /* URL */,
 666                     0 /* encoding */,
 667                     XML_PARSE_XINCLUDE);
 668     if (!doc)
 669     {
 670         p->diagnostic = YAZ_BIB1_SYSTEM_ERROR_IN_PRESENTING_RECORDS;
 671         return 0;
 672     }
 673
 674     if (window_size >= 0)
 675     {
 676         xmlNodePtr node = xmlDocGetRootElement(doc);
 677         const char *snippet_str = snippet_doc(p, 0, window_size);
 678         xmlDocPtr snippet_doc = xmlParseMemory(snippet_str, strlen(snippet_str));
 679         xmlAddChild(node, xmlDocGetRootElement(snippet_doc));
 680     }
 681     if (!schema->stylesheet_xsp)
 682         resDoc = doc;
 683     else
 684     {
 685         resDoc = xsltApplyStylesheet(schema->stylesheet_xsp,
 686                                      doc, params);
 687         xmlFreeDoc(doc);
 688     }
 689     if (!resDoc)
 690     {
 691         p->diagnostic = YAZ_BIB1_SYSTEM_ERROR_IN_PRESENTING_RECORDS;
 692     }
 693     else if (p->input_format == VAL_NONE || p->input_format == VAL_TEXT_XML)
 694     {
 695         xmlChar *buf_out;
 696         int len_out;
 697
 698         xsltSaveResultToString(&buf_out, &len_out, resDoc,
 699                                schema->stylesheet_xsp);
 700
 701         p->output_format = VAL_TEXT_XML;
 702         p->rec_len = len_out;
 703         p->rec_buf = odr_malloc(p->odr, p->rec_len);
 704         memcpy(p->rec_buf, buf_out, p->rec_len);
 705
 706         xmlFree(buf_out);
 707     }
 708     else if (p->output_format == VAL_SUTRS)
 709     {
 710         xmlChar *buf_out;
 711         int len_out;
 712
 713         xsltSaveResultToString(&buf_out, &len_out, resDoc,
 714                                schema->stylesheet_xsp);
 715
 716         p->output_format = VAL_SUTRS;
 717         p->rec_len = len_out;
 718         p->rec_buf = odr_malloc(p->odr, p->rec_len);
 719         memcpy(p->rec_buf, buf_out, p->rec_len);
 720
 721         xmlFree(buf_out);
 722     }
 723     else
 724     {
 725         p->diagnostic = YAZ_BIB1_RECORD_SYNTAX_UNSUPP;
 726     }
 727     xmlFreeDoc(resDoc);
 728     return 0;
 729 }
 730
 731 static struct recType filter_type = {
 732     0,
 733     "xslt",
 734     filter_init,
 735     filter_config,
 736     filter_destroy,
 737     filter_extract,
 738     filter_retrieve
 739 };
 740
 741 RecType
 742 #ifdef IDZEBRA_STATIC_XSLT
 743 idzebra_filter_xslt
 744 #else
 745 idzebra_filter
 746 #endif
 747
 748 [] = {
 749     &filter_type,
 750     0,
 751 };
 752 /*
 753  * Local variables:
 754  * c-basic-offset: 4
 755  * indent-tabs-mode: nil
 756  * End:
 757  * vim: shiftwidth=4 tabstop=8 expandtab
 758  */
 759