Moved isam headers to include/idzebra.

[idzebra-moved-to-github.git] / include / rset.h

diff --git a/include/rset.h b/include/rset.h
index ae1dd37..b364aee 100644 (file)
--- a/include/rset.h
+++ b/include/rset.h
@@ -1,4 +1,4 @@
-/* $Id: rset.h,v 1.37 2004-10-15 10:07:32 heikki Exp $
+/* $Id: rset.h,v 1.43 2004-12-08 14:02:36 adam Exp $
    Copyright (C) 1995,1996,1997,1998,1999,2000,2001,2002
    Index Data Aps
 
@@ -29,9 +29,9 @@ Free Software Foundation, 59 Temple Place - Suite 330, Boston, MA
 
 /* unfortunately we need the isam includes here, for the arguments for */
 /* rsisamX_create */
-#include <isamb.h> 
-#include <isamc.h> 
-#include <isams.h> 
+#include <idzebra/isamb.h> 
+#include <idzebra/isamc.h> 
+#include <idzebra/isams.h> 
 
 #ifdef __cplusplus
 extern "C" {
@@ -40,14 +40,31 @@ extern "C" {
 typedef struct rsfd *RSFD; /* Rset "file descriptor" */
 typedef struct rset *RSET; /* Result set */
 
-/*
-typedef struct terminfo *TERMID; 
-*/
-typedef int TERMID; 
-       /* term thing for the rsets. They don't need to   */
-       /* know what it is. FIXME - define that somewhere */
-/* using int while testing, to get more type checking to work */
 
+/** 
+ * rset_term is all we need to know of a term to do ranking etc. 
+ * As far as the rsets are concerned, it is just a dummy pointer to
+ * be passed around.
+ */
+
+struct rset_term {
+    /** the term itself */
+    char *name;
+    char *flags;
+    int  type;
+    /** the rset corresponding to this term */
+    RSET rset;
+    /** private stuff for the ranking algorithm */
+    void *rankpriv;
+};
+
+typedef struct rset_term *TERMID; 
+TERMID rset_term_create (const char *name, int length, const char *flags,
+                                    int type, NMEM nmem);
+
+
+
+/** rsfd is a "file descriptor" for reading from a rset */
 struct rsfd {  /* the stuff common to all rsfd's. */
     RSET rset;  /* ptr to the rset this FD is opened to */
     void *priv; /* private parameters for this type */
@@ -55,13 +72,28 @@ struct rsfd {  /* the stuff common to all rsfd's. */
 };
 
 
+/** 
+ * rset_control has function pointers to all the important functions
+ * of a rset. Each type of rset will have its own control block, pointing
+ * to the functions for that type. They all have their own create function
+ * which is not part of the control block, as it takes different args for
+ * each type.
+ */
 struct rset_control
 {
-    char *desc; /* text description of set type (for debugging) */
+    /** text description of set type (for debugging) */
+    char *desc; 
 /* RSET rs_something_create(const struct rset_control *sel, ...); */
     void (*f_delete)(RSET ct);
+
+    /** recursively fills the terms array with terms. call with curterm=0 */
+    /* always counts them all into cur, but of course won't touch the term */
+    /* array past max. You can use this to count, set max=0 */
+    void (*f_getterms)(RSET ct, TERMID *terms, int maxterms, int *curterm);
+
     RSFD (*f_open)(RSET ct, int wflag);
     void (*f_close)(RSFD rfd);
+    /** forward behaves like a read, but it skips some items first */
     int (*f_forward)(RSFD rfd, void *buf, TERMID *term, const void *untilbuf);
     void (*f_pos)(RSFD rfd, double *current, double *total);
        /* returns -1,-1 if pos function not implemented for this type */
@@ -69,9 +101,25 @@ struct rset_control
     int (*f_write)(RSFD rfd, const void *buf);
 };
 
+/** rset_default_forward implements a generic forward with a read-loop */
 int rset_default_forward(RSFD rfd, void *buf, TERMID *term,
                      const void *untilbuf);
 
+/** rset_get_no_terms is a getterms function for those that don't have any */
+void rset_get_no_terms(RSET ct, TERMID *terms, int maxterms, int *curterm);
+
+/** 
+ * rset_get_one_term is a getterms function for those rsets that have
+ * exactly one term, like all rsisamX types. 
+ */
+void rset_get_one_term(RSET ct,TERMID *terms,int maxterms,int *curterm);
+
+/**
+ * key_control contains all there is to know about the keys stored in 
+ * an isam, and therefore operated by the rsets. Other than this info,
+ * all we assume is that all keys are the same size, and they can be
+ * memcpy'd around
+ */
 struct key_control {
     int key_size;
     int scope;  /* default for what level we operate (book/chapter/verse) on*/
@@ -84,6 +132,12 @@ struct key_control {
     /* FIXME - decode and encode, and lots of other stuff */
 };
 
+/**
+ * A rset is an ordered sequence of keys, either directly from an underlaying
+ * isam, or from one of the higher-level operator rsets (and, or, ...).
+ * Actually, it is "virtual base class", no pure rsets exist in the system,
+ * they all are of some derived type.
+ */
 typedef struct rset
 {
     const struct rset_control *control;
@@ -139,6 +193,10 @@ RSET rset_dup (RSET rs);
 #define rset_forward(rfd, buf, term, untilbuf) \
     (*(rfd)->rset->control->f_forward)((rfd),(buf),(term),(untilbuf))
 
+/* void rset_getterms(RSET ct, TERMID *terms, int maxterms, int *curterm); */
+#define rset_getterms(ct, terms, maxterms, curterm) \
+    (*(ct)->control->f_getterms)((ct),(terms),(maxterms),(curterm))
+
 /* int rset_pos(RSFD fd, double *current, double *total); */
 #define rset_pos(rfd,cur,tot) \
     (*(rfd)->rset->control->f_pos)( (rfd),(cur),(tot))
@@ -153,9 +211,12 @@ RSET rset_dup (RSET rs);
 /* int rset_type (RSET) */
 #define rset_type(rs) ((rs)->control->desc)
 
+/** rset_count counts or estimates the keys in it*/
+zint rset_count(RSET rs);
+
 RSET rstemp_create( NMEM nmem, const struct key_control *kcontrol,
                     int scope, 
-                    const char *temp_path);
+                    const char *temp_path, TERMID term);
 
 RSET rsnull_create(NMEM nmem, const struct key_control *kcontrol);