IsisReader: contrib/malete/mlt/pw.h Source File

00001 /*
00002         The Malete project - the Z39.2/Z39.50 database framework of OpenIsis.
00003         Version 0.9.x (patchlevel see file Version)
00004         Copyright (C) 2001-2003 by Erik Grziwotz, erik@openisis.org
00005 
00006         This library is free software; you can redistribute it and/or
00007         modify it under the terms of the GNU Lesser General Public
00008         License as published by the Free Software Foundation; either
00009         version 2.1 of the License, or (at your option) any later version.
00010 
00011         This library is distributed in the hope that it will be useful,
00012         but WITHOUT ANY WARRANTY; without even the implied warranty of
00013         MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
00014         See the GNU Lesser General Public License for more details.
00015 
00016         You should have received a copy of the GNU Lesser General Public
00017         License along with this library; if not, write to the Free Software
00018         Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
00019 
00020         see README for more information
00021 EOH */
00022 #ifndef PW_H
00023 
00024 /*
00025         $Id: pw.h,v 1.2 2005/02/23 17:09:52 kripke Exp $
00026         interface of the Malete patchwork
00027 */
00028 
00029 #define PW_VERSION "1.0"
00030 
00031 
00032 #include "core.h"
00033 
00034 
00035 typedef struct Obj Obj;
00036 
00037 
00038 /* ****************************************************************** */
00039 /*                                                                    */
00040 /* HASH TABLE                                                         */
00041 /*                                                                    */
00042 /* ****************************************************************** */
00043 
00044 #define HEDEFKEYLEN 1
00045 
00046 typedef struct HEntry HEntry;
00047 /* hmmm ... maybe this should become part of Obj */
00048 struct HEntry {
00049         HEntry *nxt;
00050         Obj    *obj;
00051         int     hv; /* hash value of this entry */
00052 #ifndef NDEBUG
00053         int     dpt;
00054 #endif
00055         int     len;
00056         char    key[HEDEFKEYLEN]; /* not 0 terminated */
00057 };
00058 
00059 /* hmmm ... maybe this should become part of Struct */
00060 typedef struct HTable {
00061         List *list;
00062         int   mask;
00063         int   nume; /* # of entries */
00064         int   dsize; /* # bytes of unlinked entries */
00065 #ifndef NDEBUG
00066         int   coll; /* # of collisions */
00067 #endif
00068 } HTable;
00069 
00070 #define HSIZ(t) (-((t)->list->fld->tag)-1) /* number of buckets */ 
00071 #define HSHIFT 1 /* rebuild factor: HSIZ(t) << HSHIFT */ 
00072 #define HESIZ(he)  (sizeof(HEntry)+(he)->len-HEDEFKEYLEN) /* entry size */ 
00073 #define HINITIAL 32 /* initial # of buckets */
00074 #define HMAXLOAD 75 /* max load factor */
00075 #define HCURLOAD(t) ( (100*(t)->nume) /  HSIZ(t) ) /* current load */ 
00076 #define HSHRINKLOAD 25 /* shrink, if HCURLOAD(t) < HSHRINKLOAD */
00077 #define HMAXFRAG 50 /* max fragmentation factor */ 
00078 #define HCURFRAG(t) ( (100*((t)->dsize)) / LSIZ((t)->list) ) /* current frag */
00079 
00080 
00081 extern HEntry* OPT_STDCALL hGet ( HTable *table, const char *key, int len );
00082 extern HEntry* OPT_STDCALL hAdd ( HTable *table, const char *key, int len );
00083 extern HEntry* OPT_STDCALL hSet ( HTable *t, const char *key, int len, Obj *o );
00084 extern int OPT_STDCALL hDel ( HTable *table, const char *key, int len );
00085 extern HTable* OPT_STDCALL hInit ( HTable *table, const char* header );
00086 extern void OPT_STDCALL hFini ( HTable *table );
00087 
00088 /* free al resources held by table */
00089 #define HFREE( table ) do { \
00090                 hFini( (table) ); \
00091                 mFree( table ); \
00092         } while (0)
00093 
00094 #ifndef NDEBUG
00095 /* debug statistics */
00096 extern void OPT_STDCALL hstat ( HTable *table );
00097 #       define HSTAT(t) hstat(t);
00098 #else
00099 # define HSTAT(t)
00100 #endif
00101 
00102 
00103 
00104 /* ****************************************************************** */
00105 /*                                                                    */
00106 /* OBJECTS AND MESSAGES                                               */
00107 /*                                                                    */
00108 /* ****************************************************************** */
00109 
00110 typedef Fld * Msg;
00111 typedef struct Qry Qry; /* query implemented by dbo */
00112 
00113 
00114 /*
00115         dispatch message "msg", starting at object obj.
00116 
00117         -----------------------------------
00118         Syntax and semantics of messages
00119 
00120         A message is basically an array of fields - usually of length 1. The leader
00121         of this array containes the messagename, denoting a method, and possibly
00122         options. The mesagename has to be given in the leader's primary value, the
00123         options in following subfields.  Data to be processed is contained in the
00124         following fields - if any. The messagename may contain subobject specifiers,
00125         which have to be separated by a '.'. Besides this the evaluation of the
00126         given leader is solely in the responsibility of the method invoked. The
00127         message evaluation may change the given message. The significant length of a
00128         messagename may be limited to four bytes. A leader should not be longer
00129         than DEFBLKLEN bytes, though some messages may allow longer sizes. Some
00130         messagenames may use special characters denoting a special treatment of the
00131         given leader - thus such characters should not be used for ordinary
00132         messagenames. The result of the evaluation, if any, is always written to
00133         env.out.
00134 */
00135 typedef int OPT_STDCALL disp ( Obj *self, Msg msg );
00136 
00137 /*
00138         the general form of an object
00139         send it a message using that->snd(msg)
00140         In general, snd must return <0 on error, >=0 else
00141 */
00142 struct Obj {
00143         disp *snd; /* method implementation */
00144 };
00148 extern int OPT_STDCALL oObj ( Obj *self, Msg msg );
00149 
00150 
00151 typedef struct Struct Struct;
00152 
00153 typedef Obj* OPT_STDCALL factory ( Struct *self, const char *key, int len );
00154 /*
00155         an object with variable number of childs
00156 */
00157 struct Struct {
00158         disp    *snd; /* method implementation */
00159         HTable  *reg; /* child registry */
00160         factory *fac; /* child factory */
00161 };
00165 extern int OPT_STDCALL oStruct ( Struct *self, Msg msg );
00166 
00167 
00171 typedef struct Ses {
00172         disp    *snd;
00173         HTable  *reg; /* main registry */
00174         factory *fac; /* main factory */
00175         Sink    *out; /* main env.out for this session */
00176         Sink    *err; /* env.err for this session */
00177         unsigned rid; /* last rid written */
00178         Qry     *qry; /* array of q queries */
00179         lolo     req; /* request counter */
00180         /* options */
00181         char    *at; /* default target */
00182         unsigned r; /* max # of records per read, 0 = unlimited */
00183         unsigned q; /* max # of open query cursors != 0 */
00184         unsigned s; /* max # of results in search set, 0 = unlimited */
00185 } Ses;
00186 extern int  OPT_STDCALL oSes ( Ses *self, Msg msg );
00187 
00188 /*
00189         default main factory (i.e. for the session).
00190         scans the environment options for defined objects
00191 */
00192 extern Obj* OPT_STDCALL facMain ( Ses *self, const char *key, int len );
00193 
00194 /* init session */
00195 extern void sInit (Ses *s);
00196 
00197 
00198 extern Ses *ses; /* current session */
00199 
00200 /*
00201         main dispatcher
00202 */
00203 #define dispatch( msg ) ses->snd((Obj*)ses, msg)
00204 
00205 
00206 /*
00207         object linked to a session on some remote server
00208 */
00209 typedef struct Srv {
00210         disp *snd; /* method implementation */
00211         file *con; /* connection */
00212 } Srv;
00216 extern int OPT_STDCALL oSrv ( Srv *self, Msg msg );
00217 
00218 
00219 /*
00220         database object
00221         NOTE that these are childs of session, so all status is per session.
00222 */
00223 typedef struct Dbo {
00224         disp    *snd;
00225         HTable  *reg; /* views etc */
00226         factory *fac; /* child factory */
00227         Db      *db;  /* shared by the Dbos */
00228         Qry     *qry; /* chain of queries */
00229         unsigned qid; /* number of last query, 0 = none */
00230         unsigned rid; /* number of last written rec, 0 = none */
00231         /* options */
00232         unsigned p; /* position limit for snapshot read, 0 = none */
00233 } Dbo;
00237 extern int OPT_STDCALL oDbo ( Dbo *self, Msg msg );
00238 
00239 extern Dbo *newDbo ( char *name ); /* constructor */
00240 extern void delDbo ( Dbo *self ); /* destructor */
00241 
00242 
00243 /* ****************************************************************** */
00244 /*                                                                    */
00245 /* HANDLERS FOR VARIOUS STANDARD MESSAGES                             */
00246 /*                                                                    */
00247 /* ****************************************************************** */
00248 
00249 
00250 /*
00251         Process a pipe message '|'.
00252         The leader is parsed for the subfields '|'. Each of which should contain a
00253         valid messagename, options may be given in following subfields terminated by
00254         the next '|' subfield or the end of the leader. The output of the first
00255         method is used as data input for the next and so on. The first submessage
00256         may start directly after the primary field w/o the '|' identifier.
00257 */
00258 extern int OPT_STDCALL mPipe ( Obj *self, Msg msg );
00259 
00260 /*
00261         Process a compound message ';'.
00262         The leader is parsed for the subfields ';'. Each of which should contain a
00263         valid messagename, options may be given in following subfields terminated by
00264         the next ';' subfield or the end of the leader. Each message is processed
00265         separately, given data is used for all messages. The first submessage may
00266         start directly after the primary field w/o the ';' identifier.
00267 */
00268 extern int OPT_STDCALL mComp ( Obj *self, Msg msg );
00269 
00270 /*
00271         Process a comment message '#'.
00272 */
00273 extern int OPT_STDCALL mComm ( Obj *self, Msg msg );
00274 
00275 
00276 #define PW_H
00277 #endif /* PW_H */