Extend the ranking interface so staticrank is passed to calc method.

[idzebra-moved-to-github.git] / index / rankstatic.c

diff --git a/index/rankstatic.c b/index/rankstatic.c
new file mode 100644 (file)
index 0000000..a17055f
--- /dev/null
+++ b/index/rankstatic.c
@@ -0,0 +1,156 @@
+/* $Id: rankstatic.c,v 1.1 2005-08-19 09:21:34 adam Exp $
+   Copyright (C) 1995-2005
+   Index Data ApS
+
+This file is part of the Zebra server.
+
+Zebra is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 2, or (at your option) any later
+version.
+
+Zebra is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+for more details.
+
+You should have received a copy of the GNU General Public License
+along with Zebra; see the file LICENSE.zebra.  If not, write to the
+Free Software Foundation, 59 Temple Place - Suite 330, Boston, MA
+02111-1307, USA.
+*/
+
+#include <stdio.h>
+#include <assert.h>
+#ifdef WIN32
+#include <io.h>
+#endif
+#if HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+
+#include "index.h"
+
+static int log_level = 0;
+static int log_initialized = 0;
+
+struct rank_set_info {
+    int no_rank_entries;
+};
+
+/*
+ * create: Creates/Initialises this rank handler. This routine is 
+ *  called exactly once. The routine returns the class_handle.
+ */
+static void *create (ZebraHandle zh)
+{
+    if (!log_initialized)
+    {
+        log_level = yaz_log_module_level("rankstatic");
+        log_initialized = 1;
+    }
+    yaz_log(log_level, "rank-static create");
+    return 0;
+}
+
+/*
+ * destroy: Destroys this rank handler. This routine is called
+ *  when the handler is no longer needed - i.e. when the server
+ *  dies. The class_handle was previously returned by create.
+ */
+static void destroy (struct zebra_register *reg, void *class_handle)
+{
+    yaz_log(log_level, "rank-static destroy");
+}
+
+
+/**
+ * begin: Prepares beginning of "real" ranking. Called once for
+ *  each result set. The returned handle is a "set handle" and
+ *  will be used in each of the handlers below.
+ */
+static void *begin (struct zebra_register *reg, 
+                    void *class_handle, RSET rset, NMEM nmem,
+                    TERMID *terms, int numterms)
+{
+    struct rank_set_info *si = 
+        (struct rank_set_info *) nmem_malloc (nmem, sizeof(*si));
+    int i;
+
+    yaz_log(log_level, "rank-static begin");
+    /* count how many terms are ranked (2=102 or similar) */
+    si->no_rank_entries = 0;
+    for (i = 0; i < numterms; i++)
+    {
+        yaz_log(log_level, "i=%d flags=%s '%s'", i, 
+                terms[i]->flags, terms[i]->name );
+       if (!strncmp (terms[i]->flags, "rank,", 5)) 
+           (si->no_rank_entries)++;
+    }
+    return si;
+}
+
+/*
+ * end: Terminates ranking process. Called after a result set
+ *  has been ranked.
+ */
+static void end (struct zebra_register *reg, void *set_handle)
+{
+    yaz_log(log_level, "rank-static end");
+}
+
+
+/**
+ * add: Called for each word occurence in a result set. This routine
+ *  should be as fast as possible. This routine should "incrementally"
+ *  update the score.
+ */
+static void add (void *set_handle, int seqno, TERMID term)
+{
+}
+
+/*
+ * calc: Called for each document in a result. This handler should 
+ *  produce a score based on previous call(s) to the add handler. The
+ *  score should be between 0 and 1000. If score cannot be obtained
+ *  -1 should be returned.
+ */
+static int calc (void *set_handle, zint sysno, zint staticrank)
+{
+    struct rank_set_info *si = (struct rank_set_info *) set_handle;
+
+    if (!si->no_rank_entries)
+       return -1;   /* ranking not enabled for any terms */
+
+    return staticrank+10;
+}
+
+/*
+ * Pseudo-meta code with sequence of calls as they occur in a
+ * server. Handlers are prefixed by --:
+ *
+ *     server init
+ *     -- create
+ *     foreach search
+ *        rank result set
+ *        -- begin
+ *        foreach record
+ *           foreach word
+ *              -- add
+ *           -- calc
+ *        -- end
+ *     -- destroy
+ *     server close
+ */
+
+static struct rank_control rank_control = {
+    "rank-static",
+    create,
+    destroy,
+    begin,
+    end,
+    calc,
+    add,
+};
+ 
+struct rank_control *rank_static_class = &rank_control;