Added support for Z39.50 character set negotiation. This allows
[yazproxy-moved-to-github.git] / src / yaz-proxy-config.cpp
index 772b678..76259cf 100644 (file)
@@ -1,5 +1,5 @@
-/* $Id: yaz-proxy-config.cpp,v 1.5 2004-08-10 09:02:16 adam Exp $
-   Copyright (c) 1998-2004, Index Data.
+/* $Id: yaz-proxy-config.cpp,v 1.19 2005-05-18 20:15:22 adam Exp $
+   Copyright (c) 1998-2005, Index Data.
 
 This file is part of the yaz-proxy.
 
@@ -20,25 +20,98 @@ Free Software Foundation, 59 Temple Place - Suite 330, Boston, MA
  */
 
 #include <ctype.h>
+
+#if HAVE_DLFCN_H
+#include <dlfcn.h>
+#endif
+
 #include <yaz/log.h>
-#include <yazproxy/proxy.h>
+#include "proxyp.h"
 
-#if HAVE_XSLT
-#include <libxml/parser.h>
-#include <libxml/tree.h>
-#include <libxslt/xsltutils.h>
-#include <libxslt/transform.h>
+
+class Yaz_ProxyModule {
+private:
+    void *m_dl_handle;                /* dlopen/close handle */
+    Yaz_ProxyModule_entry *m_entry;
+    Yaz_ProxyModule *m_next; 
+    void *m_user_handle;              /* user handle */
+public:
+    Yaz_ProxyModule(void *dl_handle, Yaz_ProxyModule_entry *ent,
+                   Yaz_ProxyModule *next);
+    ~Yaz_ProxyModule();
+    
+    Yaz_ProxyModule *get_next() { return m_next; };
+    int is_module(const char *name);
+    int authenticate(const char *target_name, void *element_ptr,
+                    const char *user, const char *group, const char *password);
+};
+
+int Yaz_ProxyModule::is_module(const char *type)
+{
+    if (!type || !strcmp(m_entry->module_name, type))
+       return 1;
+    return 0;
+}
+
+Yaz_ProxyModule::Yaz_ProxyModule(void *dl_handle, Yaz_ProxyModule_entry *ent,
+                                Yaz_ProxyModule *next)
+{
+    m_dl_handle = dl_handle;
+    m_entry = ent;
+    m_next = next;
+    m_user_handle = 0;
+    if (m_entry->int_version == 0)
+    {
+       struct Yaz_ProxyModule_int0 *int0 =
+           reinterpret_cast<Yaz_ProxyModule_int0 *>(m_entry->fl);
+       if (int0->init)
+           m_user_handle = (*int0->init)();
+    }
+}
+
+Yaz_ProxyModule::~Yaz_ProxyModule()
+{
+    if (m_entry->int_version == 0)
+    {
+       struct Yaz_ProxyModule_int0 *int0 =
+           reinterpret_cast<Yaz_ProxyModule_int0 *>(m_entry->fl);
+       if (int0->destroy)
+           (*int0->destroy)(m_user_handle);
+    }
+#if HAVE_DLFCN_H
+    dlclose(m_dl_handle);
 #endif
+}
+
+int Yaz_ProxyModule::authenticate(const char *name,
+                                 void *element_ptr,
+                                 const char *user, const char *group,
+                                 const char *password)
+{
+    if (m_entry->int_version == 0)
+    {
+       struct Yaz_ProxyModule_int0 *int0 =
+           reinterpret_cast<Yaz_ProxyModule_int0 *>(m_entry->fl);
+       
+       if (!int0->authenticate)
+           return YAZPROXY_RET_NOT_ME;
+       return (*int0->authenticate)(m_user_handle, name, element_ptr,
+                                    user, group, password);
+    }
+    return YAZPROXY_RET_NOT_ME;
+}
 
 class Yaz_ProxyConfigP {
     friend class Yaz_ProxyConfig;
 
-    int m_copy;
+    Yaz_ProxyModule *m_modules;
 
     int mycmp(const char *hay, const char *item, size_t len);
     int match_list(int v, const char *m);
     int atoi_l(const char **cp);
 #if HAVE_XSLT
+    void load_modules(void);
+    void unload_modules(void);
     int check_schema(xmlNodePtr ptr, Z_RecordComposition *comp,
                     const char *schema_identifier);
     xmlDocPtr m_docPtr;
@@ -47,7 +120,10 @@ class Yaz_ProxyConfigP {
                            int *limit_bw, int *limit_pdu, int *limit_req,
                            int *target_idletime, int *client_idletime,
                            int *keepalive_limit_bw, int *keepalive_limit_pdu,
-                           int *pre_init, const char **cql2rpn);
+                           int *pre_init, const char **cql2rpn,
+                           const char **negotiation_charset,
+                           const char **negotiation_lang,
+                           const char **target_charset);
     void return_limit(xmlNodePtr ptr,
                      int *limit_bw, int *limit_pdu, int *limit_req);
     int check_type_1(ODR odr, xmlNodePtr ptr, Z_RPNQuery *query,
@@ -60,28 +136,98 @@ class Yaz_ProxyConfigP {
                                char **addinfo);
     int check_type_1_structure(ODR odr, xmlNodePtr ptr, Z_RPNStructure *q,
                               char **addinfo);
+    int get_explain_ptr(const char *host, const char *db,
+                       xmlNodePtr *ptr_target, xmlNodePtr *ptr_explain);
 #endif
+    Yaz_ProxyConfigP();
+    ~Yaz_ProxyConfigP();
 };
 
-Yaz_ProxyConfig::Yaz_ProxyConfig()
+Yaz_ProxyConfigP::Yaz_ProxyConfigP()
 {
-    m_cp = new Yaz_ProxyConfigP;
-    m_cp->m_copy = 0;
 #if HAVE_XSLT
-    m_cp->m_docPtr = 0;
-    m_cp->m_proxyPtr = 0;
+    m_docPtr = 0;
+    m_proxyPtr = 0;
 #endif
+    m_modules = 0;
 }
 
-Yaz_ProxyConfig::~Yaz_ProxyConfig()
+Yaz_ProxyConfigP::~Yaz_ProxyConfigP()
 {
 #if HAVE_XSLT
-    if (!m_cp->m_copy && m_cp->m_docPtr)
-       xmlFreeDoc(m_cp->m_docPtr);
+    if (m_docPtr)
+       xmlFreeDoc(m_docPtr);
 #endif
+}
+
+Yaz_ProxyConfig::Yaz_ProxyConfig()
+{
+    m_cp = new Yaz_ProxyConfigP;
+}
+
+Yaz_ProxyConfig::~Yaz_ProxyConfig()
+{
     delete m_cp;
 }
 
+#if HAVE_XSLT
+void Yaz_ProxyConfigP::unload_modules()
+{
+    Yaz_ProxyModule *m = m_modules;
+    while (m)
+    {
+       Yaz_ProxyModule *m_next = m->get_next();
+       delete m;
+       m = m_next;
+    }
+    m_modules = 0;
+}
+#endif
+
+#if HAVE_XSLT
+void Yaz_ProxyConfigP::load_modules()
+{
+    if (!m_proxyPtr)
+       return;
+    xmlNodePtr ptr;
+    for (ptr = m_proxyPtr->children; ptr; ptr = ptr->next)
+    {
+       const char *fname;
+       if (ptr->type == XML_ELEMENT_NODE 
+           && !strcmp((const char *) ptr->name, "module")
+           && (fname = get_text(ptr)))
+       {
+#if HAVE_DLFCN_H
+           void *dl_handle = dlopen(fname, RTLD_NOW|RTLD_GLOBAL);
+           if (dl_handle)
+           {
+               Yaz_ProxyModule_entry *fl_ptr = 0;
+               fl_ptr = reinterpret_cast<Yaz_ProxyModule_entry *> 
+                   (dlsym(dl_handle, "yazproxy_module"));
+               if (fl_ptr)
+               {
+                   Yaz_ProxyModule *m = new Yaz_ProxyModule(dl_handle,
+                                                            fl_ptr,
+                                                            m_modules);
+                   m_modules = m;
+                   yaz_log(YLOG_LOG, "Loading %s OK", fname);
+               }
+               else
+               {
+                   yaz_log(YLOG_WARN, "Loading %s FAIL: missing yazproxy_module symbol", fname);
+                   dlclose(dl_handle);
+               }
+           }
+           else
+               yaz_log(YLOG_WARN, "Loading %s FAIL: dlopen failed", fname);
+#else
+           yaz_log(YLOG_WARN, "Loading &s FAIL: dl unsupported", fname);
+#endif
+       }
+    }
+}
+#endif
+
 int Yaz_ProxyConfig::read_xml(const char *fname)
 {
 #if HAVE_XSLT
@@ -89,14 +235,18 @@ int Yaz_ProxyConfig::read_xml(const char *fname)
 
     if (!ndoc)
     {
-       yaz_log(LOG_WARN, "Config file %s not found or parse error", fname);
+       yaz_log(YLOG_WARN, "Config file %s not found or parse error", fname);
        return -1;  // no good
     }
+    int noSubstitutions = xmlXIncludeProcess(ndoc);
+    if (noSubstitutions == -1)
+       yaz_log(YLOG_WARN, "XInclude processing failed on config %s", fname);
+
     xmlNodePtr proxyPtr = xmlDocGetRootElement(ndoc);
     if (!proxyPtr || proxyPtr->type != XML_ELEMENT_NODE ||
        strcmp((const char *) proxyPtr->name, "proxy"))
     {
-       yaz_log(LOG_WARN, "No proxy element in %s", fname);
+       yaz_log(YLOG_WARN, "No proxy element in %s", fname);
        xmlFreeDoc(ndoc);
        return -1;
     }
@@ -106,6 +256,9 @@ int Yaz_ProxyConfig::read_xml(const char *fname)
     if (m_cp->m_docPtr)
        xmlFreeDoc(m_cp->m_docPtr);
     m_cp->m_docPtr = ndoc;
+
+    m_cp->unload_modules();
+    m_cp->load_modules();
     return 0;
 #else
     return -2;
@@ -174,7 +327,10 @@ void Yaz_ProxyConfigP::return_target_info(xmlNodePtr ptr,
                                          int *keepalive_limit_bw,
                                          int *keepalive_limit_pdu,
                                          int *pre_init,
-                                         const char **cql2rpn)
+                                         const char **cql2rpn,
+                                         const char **negotiation_charset,
+                                         const char **negotiation_lang,
+                                         const char **target_charset)
 {
     *pre_init = 0;
     int no_url = 0;
@@ -238,6 +394,27 @@ void Yaz_ProxyConfigP::return_target_info(xmlNodePtr ptr,
            if (t)
                *cql2rpn = t;
        }
+       if (ptr->type == XML_ELEMENT_NODE 
+           && !strcmp((const char *) ptr->name, "target-charset"))
+       {
+           const char *t = get_text(ptr);
+           if (t && target_charset)
+               *target_charset = t;
+       }
+       if (ptr->type == XML_ELEMENT_NODE 
+           && !strcmp((const char *) ptr->name, "negotiation-charset"))
+       {
+           const char *t = get_text(ptr);
+           if (t)
+               *negotiation_charset = t;
+       }
+       if (ptr->type == XML_ELEMENT_NODE 
+           && !strcmp((const char *) ptr->name, "negotiation-lang"))
+       {
+           const char *t = get_text(ptr);
+           if (t)
+               *negotiation_lang = t;
+       }
     }
 }
 #endif
@@ -351,8 +528,8 @@ int Yaz_ProxyConfigP::check_type_1_attributes(ODR odr, xmlNodePtr ptrl,
 
 #if HAVE_XSLT
 int Yaz_ProxyConfigP::check_type_1_structure(ODR odr, xmlNodePtr ptr,
-                                           Z_RPNStructure *q,
-                                           char **addinfo)
+                                            Z_RPNStructure *q,
+                                            char **addinfo)
 {
     if (q->which == Z_RPNStructure_complex)
     {
@@ -443,11 +620,154 @@ int Yaz_ProxyConfigP::check_schema(xmlNodePtr ptr, Z_RecordComposition *comp,
 }
 #endif
 
+const char *Yaz_ProxyConfig::check_mime_type(const char *path)
+{
+    struct {
+       const char *mask;
+       const char *type;
+    } types[] = {
+       {".xml", "text/xml"},
+       {".xsl", "text/xml"},
+       {".tkl", "text/xml"},
+       {".xsd", "text/xml"},
+       {".html", "text/html"},
+       {".jpg", "image/jpeg"},
+       {".png", "image/png"},
+       {".gif", "image/gif"},
+       {0, "text/plain"},
+       {0, 0},
+    };
+    int i;
+    size_t plen = strlen (path);
+    for (i = 0; types[i].type; i++)
+       if (types[i].mask == 0)
+           return types[i].type;
+       else
+       {
+           size_t mlen = strlen(types[i].mask);
+           if (plen > mlen && !memcmp(path+plen-mlen, types[i].mask, mlen))
+               return types[i].type;
+       }
+    return "application/octet-stream";
+}
+
+
+void Yaz_ProxyConfig::target_authentication(const char *name,
+                                           ODR odr, Z_InitRequest *req)
+{
+#if HAVE_XSLT
+    xmlNodePtr ptr = m_cp->find_target_node(name, 0);
+    if (!ptr)
+       return ;
+    
+    for (ptr = ptr->children; ptr; ptr = ptr->next)
+       if (ptr->type == XML_ELEMENT_NODE &&
+           !strcmp((const char *) ptr->name, "target-authentication"))
+       {
+           struct _xmlAttr *attr;
+           const char *type = "open";
+           for (attr = ptr->properties; attr; attr = attr->next)
+           {
+               if (!strcmp((const char *) attr->name, "type") &&
+                   attr->children && attr->children->type == XML_TEXT_NODE)
+                   type = (const char *) attr->children->content;
+           }
+           const char *t = m_cp->get_text(ptr);
+           if (!t || !strcmp(type, "none"))
+               req->idAuthentication = 0;
+           else if (!strcmp(type, "anonymous"))
+           {
+               req->idAuthentication =
+                   (Z_IdAuthentication *)
+                   odr_malloc (odr, sizeof(*req->idAuthentication));
+               req->idAuthentication->which =
+                   Z_IdAuthentication_anonymous;
+               req->idAuthentication->u.anonymous = odr_nullval();
+           }
+           else if (!strcmp(type, "open"))
+           {
+               req->idAuthentication =
+                   (Z_IdAuthentication *)
+                   odr_malloc (odr, sizeof(*req->idAuthentication));
+               req->idAuthentication->which =
+                   Z_IdAuthentication_open;
+               req->idAuthentication->u.open = odr_strdup (odr, t);
+           }
+           else if (!strcmp(type, "idPass"))
+           {
+               char user[64], group[64], password[64];
+               *group = '\0';
+               *password = '\0';
+               *user = '\0';
+               sscanf(t, "%63[^:]:%63[^:]:%63s", user, group, password);
+               
+               req->idAuthentication =
+                   (Z_IdAuthentication *)
+                   odr_malloc (odr, sizeof(*req->idAuthentication));
+               req->idAuthentication->which =
+                   Z_IdAuthentication_idPass;
+               req->idAuthentication->u.idPass =
+                   (Z_IdPass*) odr_malloc(odr, sizeof(Z_IdPass));
+               req->idAuthentication->u.idPass->userId =
+                   *user ? odr_strdup(odr, user) : 0;
+               req->idAuthentication->u.idPass->groupId =
+                   *group ? odr_strdup(odr, group) : 0;
+               req->idAuthentication->u.idPass->password =
+                   *password ? odr_strdup(odr, password) : 0;
+           }
+       }
+#endif
+}
+
+int Yaz_ProxyConfig::client_authentication(const char *name,
+                                          const char *user,
+                                          const char *group,
+                                          const char *password)
+{
+    int ret = YAZPROXY_RET_NOT_ME;
+#if HAVE_XSLT
+    xmlNodePtr ptr;
+    ptr = m_cp->find_target_node(name, 0);
+    if (!ptr)
+       return 1;
+    for (ptr = ptr->children; ptr; ptr = ptr->next)
+       if (ptr->type == XML_ELEMENT_NODE &&
+           !strcmp((const char *) ptr->name, "client-authentication"))
+       {
+           struct _xmlAttr *attr;
+           const char *module_name = 0;
+           for (attr = ptr->properties; attr; attr = attr->next)
+           {
+               if (!strcmp((const char *) attr->name, "module") &&
+                   attr->children && attr->children->type == XML_TEXT_NODE)
+                   module_name = (const char *) attr->children->content;
+           }
+           Yaz_ProxyModule *m = m_cp->m_modules;
+           for (; m; m = m->get_next())
+           {
+               if (m->is_module(module_name))
+               {
+                   ret = m->authenticate(name, ptr, user, group, password);
+                   if (ret != YAZPROXY_RET_NOT_ME)
+                       break;
+               }
+           }
+       }
+#endif
+    if (ret == YAZPROXY_RET_PERM)
+       return 0;
+    return 1;
+}
+
 int Yaz_ProxyConfig::check_syntax(ODR odr, const char *name,
                                  Odr_oid *syntax, Z_RecordComposition *comp,
                                  char **addinfo,
                                  char **stylesheet, char **schema,
-                                 char **backend_type)
+                                 char **backend_type,
+                                 char **backend_charset,
+                                 char **usemarcon_ini_stage1,
+                                 char **usemarcon_ini_stage2
+                                 )
 {
     if (stylesheet)
     {
@@ -464,6 +784,21 @@ int Yaz_ProxyConfig::check_syntax(ODR odr, const char *name,
        xfree (*backend_type);
        *backend_type = 0;
     }
+    if (backend_charset)
+    {
+       xfree (*backend_charset);
+       *backend_charset = 0;
+    }
+    if (usemarcon_ini_stage1)
+    {
+       xfree (*usemarcon_ini_stage1);
+       *usemarcon_ini_stage1 = 0;
+    }
+    if (usemarcon_ini_stage2)
+    {
+       xfree (*usemarcon_ini_stage2);
+       *usemarcon_ini_stage2 = 0;
+    }
 #if HAVE_XSLT
     int syntax_has_matched = 0;
     xmlNodePtr ptr;
@@ -483,6 +818,9 @@ int Yaz_ProxyConfig::check_syntax(ODR odr, const char *name,
            const char *match_stylesheet = 0;
            const char *match_identifier = 0;
            const char *match_backend_type = 0;
+           const char *match_backend_charset = 0;
+           const char *match_usemarcon_ini_stage1 = 0;
+           const char *match_usemarcon_ini_stage2 = 0;
            struct _xmlAttr *attr;
            for (attr = ptr->properties; attr; attr = attr->next)
            {
@@ -505,6 +843,18 @@ int Yaz_ProxyConfig::check_syntax(ODR odr, const char *name,
                    attr->children && attr->children->type == XML_TEXT_NODE)
                    match_backend_type = (const char *)
                        attr->children->content;
+               if (!strcmp((const char *) attr->name, "backendcharset") &&
+                   attr->children && attr->children->type == XML_TEXT_NODE)
+                   match_backend_charset = (const char *)
+                       attr->children->content;
+               if (!strcmp((const char *) attr->name, "usemarconstage1") &&
+                   attr->children && attr->children->type == XML_TEXT_NODE)
+                   match_usemarcon_ini_stage1 = (const char *)
+                       attr->children->content;
+               if (!strcmp((const char *) attr->name, "usemarconstage2") &&
+                   attr->children && attr->children->type == XML_TEXT_NODE)
+                   match_usemarcon_ini_stage2 = (const char *)
+                       attr->children->content;
            }
            if (match_type)
            {
@@ -547,6 +897,21 @@ int Yaz_ProxyConfig::check_syntax(ODR odr, const char *name,
                    xfree(*backend_type);
                    *backend_type = xstrdup(match_backend_type);
                }
+               if (backend_charset && match_backend_charset)
+               {
+                   xfree(*backend_charset);
+                   *backend_charset = xstrdup(match_backend_charset);
+               }
+               if (usemarcon_ini_stage1 && match_usemarcon_ini_stage1)
+               {
+                   xfree(*usemarcon_ini_stage1);
+                   *usemarcon_ini_stage1 = xstrdup(match_usemarcon_ini_stage1);
+               }
+               if (usemarcon_ini_stage1 && match_usemarcon_ini_stage2)
+               {
+                   xfree(*usemarcon_ini_stage2);
+                   *usemarcon_ini_stage2 = xstrdup(match_usemarcon_ini_stage2);
+               }
                if (match_marcxml)
                {
                    return -1;
@@ -662,7 +1027,11 @@ int Yaz_ProxyConfig::get_target_no(int no,
                                   int *keepalive_limit_bw,
                                   int *keepalive_limit_pdu,
                                   int *pre_init,
-                                  const char **cql2rpn)
+                                  const char **cql2rpn,
+                                  const char **authentication,
+                                  const char **negotiation_charset,
+                                  const char **negotiation_lang,
+                                  const char **target_charset)
 {
 #if HAVE_XSLT
     xmlNodePtr ptr;
@@ -689,7 +1058,8 @@ int Yaz_ProxyConfig::get_target_no(int no,
                    limit_bw, limit_pdu, limit_req,
                    target_idletime, client_idletime,
                    keepalive_limit_bw, keepalive_limit_pdu,
-                   pre_init, cql2rpn);
+                   pre_init, cql2rpn,
+                   negotiation_charset, negotiation_lang, target_charset);
                return 1;
            }
            i++;
@@ -757,57 +1127,119 @@ void Yaz_ProxyConfig::get_generic_info(int *log_mask,
 #endif
 }
 
-char *Yaz_ProxyConfig::get_explain(ODR odr, const char *name, const char *db,
-                                  int *len)
-{
 #if HAVE_XSLT
-    xmlNodePtr ptr = m_cp->find_target_node(name, db);
-    if (ptr)
+int Yaz_ProxyConfigP::get_explain_ptr(const char *host, const char *db,
+                                     xmlNodePtr *ptr_target,
+                                     xmlNodePtr *ptr_explain)
+{
+    xmlNodePtr ptr;
+    if (!m_proxyPtr)
+       return 0;
+    if (!db)
+       return 0;
+    for (ptr = m_proxyPtr->children; ptr; ptr = ptr->next)
     {
-       ptr = ptr->children;
-       for (; ptr; ptr = ptr->next)
-           if (ptr->type == XML_ELEMENT_NODE &&
-               !strcmp((const char *) ptr->name, "explain"))
+       if (ptr->type == XML_ELEMENT_NODE &&
+           !strcmp((const char *) ptr->name, "target"))
+       {
+           *ptr_target = ptr;
+           xmlNodePtr ptr = (*ptr_target)->children;
+           for (; ptr; ptr = ptr->next)
            {
-               xmlNodePtr ptr1 = ptr->children;
-               if (db)
+               if (ptr->type == XML_ELEMENT_NODE &&
+                   !strcmp((const char *) ptr->name, "explain"))
                {
-                   for (; ptr1; ptr1 = ptr1->next)
-                       if (ptr1->type == XML_ELEMENT_NODE &&
-                           !strcmp((const char *) ptr1->name, "serverInfo"))
+                   *ptr_explain = ptr;
+                   xmlNodePtr ptr = (*ptr_explain)->children;
+
+                   for (; ptr; ptr = ptr->next)
+                       if (ptr->type == XML_ELEMENT_NODE &&
+                           !strcmp((const char *) ptr->name, "serverInfo"))
                            break;
-                   if (!ptr1)
+                   if (!ptr)
                        continue;
-                   for (ptr1 = ptr1->children; ptr1; ptr1 = ptr1->next)
-                       if (ptr1->type == XML_ELEMENT_NODE &&
-                           !strcmp((const char *) ptr1->name, "database"))
+                   for (ptr = ptr->children; ptr; ptr = ptr->next)
+                       if (ptr->type == XML_ELEMENT_NODE &&
+                           !strcmp((const char *) ptr->name, "database"))
                            break;
                    
-                   if (!ptr1)
+                   if (!ptr)
                        continue;
-                   for (ptr1 = ptr1->children; ptr1; ptr1 = ptr1->next)
-                       if (ptr1->type == XML_TEXT_NODE &&
-                           ptr1->content &&
-                           !strcmp((const char *) ptr1->content, db))
+                   for (ptr = ptr->children; ptr; ptr = ptr->next)
+                       if (ptr->type == XML_TEXT_NODE &&
+                           ptr->content &&
+                           !strcmp((const char *) ptr->content, db))
                            break;
-                   if (!ptr1)
+                   if (!ptr)
                        continue;
+                   return 1;
                }
-               xmlNodePtr ptr2 = xmlCopyNode(ptr, 1);
+           }
+       }
+    }
+    return 0;
+}
+#endif
 
-               xmlDocPtr doc = xmlNewDoc((const xmlChar *) "1.0");
-               
-               xmlDocSetRootElement(doc, ptr2);
-               
-               xmlChar *buf_out;
-               xmlDocDumpMemory(doc, &buf_out, len);
-               char *content = (char*) odr_malloc(odr, *len);
-               memcpy(content, buf_out, *len);
-               
-               xmlFree(buf_out);
-               xmlFreeDoc(doc);
-               return content;
+const char *Yaz_ProxyConfig::get_explain_name(const char *db,
+                                             const char **backend_db)
+{
+#if HAVE_XSLT
+    xmlNodePtr ptr_target, ptr_explain;
+    if (m_cp->get_explain_ptr(0, db, &ptr_target, &ptr_explain)
+       && ptr_target)
+    {
+       struct _xmlAttr *attr;
+       const char *name = 0;
+       
+       for (attr = ptr_target->properties; attr; attr = attr->next)
+           if (!strcmp((const char *) attr->name, "name")
+               && attr->children
+               && attr->children->type==XML_TEXT_NODE
+               && attr->children->content 
+               && attr->children->content[0])
+           {
+               name = (const char *)attr->children->content;
+               break;
            }
+       if (name)
+       {
+           for (attr = ptr_target->properties; attr; attr = attr->next)
+               if (!strcmp((const char *) attr->name, "database"))
+               {
+                   if (attr->children
+                       && attr->children->type==XML_TEXT_NODE
+                       && attr->children->content)
+                       *backend_db = (const char *) attr->children->content;
+               }
+           return name;
+       }
+    }
+#endif
+    return 0;
+}
+
+char *Yaz_ProxyConfig::get_explain_doc(ODR odr, const char *name,
+                                      const char *db, int *len)
+{
+#if HAVE_XSLT
+    xmlNodePtr ptr_target, ptr_explain;
+    if (m_cp->get_explain_ptr(0 /* host */, db, &ptr_target, &ptr_explain))
+    {
+       xmlNodePtr ptr2 = xmlCopyNode(ptr_explain, 1);
+       
+       xmlDocPtr doc = xmlNewDoc((const xmlChar *) "1.0");
+       
+       xmlDocSetRootElement(doc, ptr2);
+       
+       xmlChar *buf_out;
+       xmlDocDumpMemory(doc, &buf_out, len);
+       char *content = (char*) odr_malloc(odr, *len);
+       memcpy(content, buf_out, *len);
+       
+       xmlFree(buf_out);
+       xmlFreeDoc(doc);
+       return content;
     }
 #endif
     return 0;
@@ -824,7 +1256,10 @@ void Yaz_ProxyConfig::get_target_info(const char *name,
                                      int *keepalive_limit_bw,
                                      int *keepalive_limit_pdu,
                                      int *pre_init,
-                                     const char **cql2rpn)
+                                     const char **cql2rpn,
+                                     const char **negotiation_charset,
+                                     const char **negotiation_lang,
+                                     const char **target_charset)
 {
 #if HAVE_XSLT
     xmlNodePtr ptr;
@@ -860,7 +1295,9 @@ void Yaz_ProxyConfig::get_target_info(const char *name,
        m_cp->return_target_info(ptr, url, limit_bw, limit_pdu, limit_req,
                                 target_idletime, client_idletime,
                                 keepalive_limit_bw, keepalive_limit_pdu,
-                                pre_init, cql2rpn);
+                                pre_init, cql2rpn,
+                                negotiation_charset, negotiation_lang,
+                                target_charset);
     }
 #else
     *url = name;