More efficient and operation.

[idzebra-moved-to-github.git] / rset / rsbool.c

diff --git a/rset/rsbool.c b/rset/rsbool.c
index d1bddb8..a20c452 100644 (file)
--- a/rset/rsbool.c
+++ b/rset/rsbool.c
@@ -4,7 +4,15 @@
  * Sebastian Hammer, Adam Dickmeiss
  *
  * $Log: rsbool.c,v $
- * Revision 1.2  1995-09-06 16:11:55  adam
+ * Revision 1.4  1995-09-08 08:54:04  adam
+ * More efficient and operation.
+ *
+ * Revision 1.3  1995/09/07  13:58:43  adam
+ * New parameter: result-set file descriptor (RSFD) to support multiple
+ * positions within the same result-set.
+ * Boolean operators: and, or, not implemented.
+ *
+ * Revision 1.2  1995/09/06  16:11:55  adam
  * More work on boolean sets.
  *
  * Revision 1.1  1995/09/06  13:27:15  adam
@@ -13,21 +21,25 @@
  */
 
 #include <stdio.h>
+#include <assert.h>
+
 #include <rsbool.h>
 #include <alexutil.h>
 
 static rset_control *r_create(const struct rset_control *sel, void *parms);
-static int r_open (rset_control *ct, int wflag);
-static void r_close (rset_control *ct);
+static RSFD r_open (rset_control *ct, int wflag);
+static void r_close (RSFD rfd);
 static void r_delete (rset_control *ct);
-static void r_rewind (rset_control *ct);
+static void r_rewind (RSFD rfd);
 static int r_count (rset_control *ct);
-static int r_read (rset_control *ct, void *buf);
-static int r_write (rset_control *ct, const void *buf);
+static int r_read_and (RSFD rfd, void *buf);
+static int r_read_or (RSFD rfd, void *buf);
+static int r_read_not (RSFD rfd, void *buf);
+static int r_write (RSFD rfd, const void *buf);
 
-static const rset_control control = 
+static const rset_control control_and = 
 {
-    "BOOL set type",
+    "AND set type",
     0,
     r_create,
     r_open,
@@ -35,25 +47,63 @@ static const rset_control control =
     r_delete,
     r_rewind,
     r_count,
-    r_read,
+    r_read_and,
     r_write
 };
 
-const rset_control *rset_kind_bool = &control;
+static const rset_control control_or = 
+{
+    "OR set type",
+    0,
+    r_create,
+    r_open,
+    r_close,
+    r_delete,
+    r_rewind,
+    r_count,
+    r_read_or,
+    r_write
+};
+
+static const rset_control control_not = 
+{
+    "NOT set type",
+    0,
+    r_create,
+    r_open,
+    r_close,
+    r_delete,
+    r_rewind,
+    r_count,
+    r_read_not,
+    r_write
+};
+
+
+const rset_control *rset_kind_and = &control_and;
+const rset_control *rset_kind_or = &control_or;
+const rset_control *rset_kind_not = &control_not;
 
 struct rset_bool_info {
     int key_size;
-    int op;
     RSET rset_l;
     RSET rset_r;
-    int more_l;
-    int more_r;
-    void *buf_l;
-    void *buf_r;
     int (*cmp)(const void *p1, const void *p2);
+    struct rset_bool_rfd *rfd_list;
 };
 
-static rset_control *r_create(const struct rset_control *sel, void *parms)
+struct rset_bool_rfd {
+    RSFD rfd_l;
+    RSFD rfd_r;
+    int  more_l;
+    int  more_r;
+    void *buf_l;
+    void *buf_r;
+    struct rset_bool_rfd *next;
+    struct rset_bool_info *info;
+};    
+
+static rset_control *r_create (const struct rset_control *sel, void *parms)
 {
     rset_control *newct;
     rset_bool_parms *bool_parms = parms;
@@ -65,58 +115,76 @@ static rset_control *r_create(const struct rset_control *sel, void *parms)
     newct->buf = xmalloc (sizeof(struct rset_bool_info));
     info = (struct rset_bool_info*) newct->buf;
     info->key_size = bool_parms->key_size;
-    info->op = bool_parms->op;
     info->rset_l = bool_parms->rset_l;
     info->rset_r = bool_parms->rset_r;
     info->cmp = bool_parms->cmp;
-    info->buf_l = xmalloc (info->key_size);
-    info->buf_r = xmalloc (info->key_size);
+    info->rfd_list = NULL;
     return newct;
 }
 
-static int r_open(rset_control *ct, int wflag)
+static RSFD r_open (rset_control *ct, int wflag)
 {
     struct rset_bool_info *info = ct->buf;
+    struct rset_bool_rfd *rfd;
 
     if (wflag)
     {
        logf (LOG_FATAL, "bool set type is read-only");
-       return -1;
+       return NULL;
     }
-    rset_open (info->rset_l, wflag);
-    rset_open (info->rset_r, wflag);
-    info->more_l = rset_read (info->rset_l, info->buf_l);
-    info->more_r = rset_read (info->rset_r, info->buf_r);
-    return 0;
+    rfd = xmalloc (sizeof(*rfd));
+    rfd->next = info->rfd_list;
+    info->rfd_list = rfd;
+
+    rfd->buf_l = xmalloc (info->key_size);
+    rfd->buf_r = xmalloc (info->key_size);
+    rfd->rfd_l = rset_open (info->rset_l, wflag);
+    rfd->rfd_r = rset_open (info->rset_r, wflag);
+    rfd->more_l = rset_read (info->rset_l, rfd->rfd_l, rfd->buf_l);
+    rfd->more_r = rset_read (info->rset_r, rfd->rfd_r, rfd->buf_r);
+    rfd->info = info;
+    return rfd;
 }
 
-static void r_close(rset_control *ct)
+static void r_close (RSFD rfd)
 {
-    struct rset_bool_info *info = ct->buf;
-
-    rset_close (info->rset_l);
-    rset_close (info->rset_r);
+    struct rset_bool_info *info = ((struct rset_bool_rfd*)rfd)->info;
+    struct rset_bool_rfd **rfdp;
+    
+    for (rfdp = &info->rfd_list; *rfdp; rfdp = &(*rfdp)->next)
+        if (*rfdp == rfd)
+        {
+            xfree ((*rfdp)->buf_l);
+            xfree ((*rfdp)->buf_r);
+            rset_close (info->rset_l, (*rfdp)->rfd_l);
+            rset_close (info->rset_r, (*rfdp)->rfd_r);
+            *rfdp = (*rfdp)->next;
+            free (rfd);
+            return;
+        }
+    logf (LOG_FATAL, "r_close but no rfd match!");
+    assert (0);
 }
 
-static void r_delete(rset_control *ct)
+static void r_delete (rset_control *ct)
 {
     struct rset_bool_info *info = ct->buf;
 
-    rset_delete (info->rset_l);
-    rset_delete (info->rset_r);
-    xfree (info->buf_l);
-    xfree (info->buf_r);
-    xfree (ct->buf);
+    assert (info->rfd_list == NULL);
+    xfree (info);
     xfree (ct);
 }
 
-static void r_rewind(rset_control *ct)
+static void r_rewind (RSFD rfd)
 {
-    struct rset_bool_info *info = ct->buf;
+    struct rset_bool_info *info = ((struct rset_bool_rfd*)rfd)->info;
+    struct rset_bool_rfd *p = rfd;
 
     logf (LOG_DEBUG, "rsbool_rewind");
-    rset_rewind (info->rset_l);
-    rset_rewind (info->rset_r);
+    rset_rewind (info->rset_l, p->rfd_l);
+    rset_rewind (info->rset_r, p->rfd_r);
+    p->more_l = rset_read (info->rset_l, p->rfd_l, p->buf_l);
+    p->more_r = rset_read (info->rset_r, p->rfd_r, p->buf_r);
 }
 
 static int r_count (rset_control *ct)
@@ -124,16 +192,128 @@ static int r_count (rset_control *ct)
     return 0;
 }
 
-static int r_read (rset_control *ct, void *buf)
+static int r_read_and (RSFD rfd, void *buf)
 {
-    struct rset_bool_info *info = ct->buf;
+    struct rset_bool_rfd *p = rfd;
+    struct rset_bool_info *info = p->info;
+
+    while (p->more_l && p->more_r)
+    {
+        int cmp;
 
-    if (!info->more_l && !info->more_r)
-        return 0;
+        cmp = (*info->cmp)(p->buf_l, p->buf_r);
+        if (!cmp)
+        {
+            memcpy (buf, p->buf_l, info->key_size);
+            p->more_l = rset_read (info->rset_l, p->rfd_l, p->buf_l);
+            p->more_r = rset_read (info->rset_r, p->rfd_r, p->buf_r);
+            return 1;
+        }
+        else if (cmp == 1)
+        {
+            memcpy (buf, p->buf_r, info->key_size);
+            p->more_r = rset_read (info->rset_r, p->rfd_r, p->buf_r);
+            return 1;
+        }
+        else if (cmp == -1)
+        {
+            memcpy (buf, p->buf_l, info->key_size);
+            p->more_l = rset_read (info->rset_l, p->rfd_l, p->buf_l);
+            return 1;
+        }
+        else if (cmp > 1)
+            p->more_r = rset_read (info->rset_r, p->rfd_r, p->buf_r);
+        else
+            p->more_l = rset_read (info->rset_l, p->rfd_l, p->buf_l);
+    }
     return 0;
 }
 
-static int r_write (rset_control *ct, const void *buf)
+static int r_read_or (RSFD rfd, void *buf)
+{
+    struct rset_bool_rfd *p = rfd;
+    struct rset_bool_info *info = p->info;
+
+    while (p->more_l || p->more_r)
+    {
+        int cmp;
+
+        if (p->more_l && p->more_r)
+            cmp = (*info->cmp)(p->buf_l, p->buf_r);
+        else if (p->more_r)
+            cmp = 2;
+        else
+            cmp = -2;
+        if (!cmp)
+        {
+            memcpy (buf, p->buf_l, info->key_size);
+            p->more_l = rset_read (info->rset_l, p->rfd_l, p->buf_l);
+            p->more_r = rset_read (info->rset_r, p->rfd_r, p->buf_r);
+            return 1;
+        }
+        else if (cmp > 0)
+        {
+            memcpy (buf, p->buf_r, info->key_size);
+            p->more_r = rset_read (info->rset_r, p->rfd_r, p->buf_r);
+            return 1;
+        }
+        else
+        {
+            memcpy (buf, p->buf_l, info->key_size);
+            p->more_l = rset_read (info->rset_l, p->rfd_l, p->buf_l);
+            return 1;
+        }
+    }
+    return 0;
+}
+
+static int r_read_not (RSFD rfd, void *buf)
+{
+    struct rset_bool_rfd *p = rfd;
+    struct rset_bool_info *info = p->info;
+
+    while (p->more_l || p->more_r)
+    {
+        int cmp;
+
+        if (p->more_l && p->more_r)
+            cmp = (*info->cmp)(p->buf_l, p->buf_r);
+        else if (p->more_r)
+            cmp = 2;
+        else
+            cmp = -2;
+        if (cmp < -1)
+        {
+            memcpy (buf, p->buf_l, info->key_size);
+            p->more_l = rset_read (info->rset_l, p->rfd_l, p->buf_l);
+            return 1;
+        }
+        else if (cmp > 1)
+            p->more_r = rset_read (info->rset_r, p->rfd_r, p->buf_r);
+        else
+        {
+            memcpy (buf, p->buf_l, info->key_size);
+            do
+            {
+                p->more_l = rset_read (info->rset_l, p->rfd_l, p->buf_l);
+                if (!p->more_l)
+                    break;
+                cmp = (*info->cmp)(p->buf_l, buf);
+            } while (cmp >= -1 && cmp <= 1);
+            do
+            {
+                p->more_r = rset_read (info->rset_r, p->rfd_r, p->buf_r);
+                if (!p->more_r)
+                    break;
+                cmp = (*info->cmp)(p->buf_r, buf);
+            } while (cmp >= -1 && cmp <= 1);
+        }
+    }
+    return 0;
+}
+
+
+static int r_write (RSFD rfd, const void *buf)
 {
     logf (LOG_FATAL, "bool set type is read-only");
     return -1;