sync code with last improvements from OpenBSD

lib/libdrm/tests/drmsl.c

@@ -0,0 +1,184 @@
+/* drmsl.c -- Skip list test
+ * Created: Mon May 10 09:28:13 1999 by faith@precisioninsight.com
+ *
+ * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
+ * All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * PRECISION INSIGHT AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: Rickard E. (Rik) Faith <faith@valinux.com>
+ *
+ * DESCRIPTION
+ *
+ * This file contains a straightforward skip list implementation.n
+ *
+ * FUTURE ENHANCEMENTS
+ *
+ * REFERENCES
+ *
+ * [Pugh90] William Pugh.  Skip Lists: A Probabilistic Alternative to
+ * Balanced Trees. CACM 33(6), June 1990, pp. 668-676.
+ *
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/time.h>
+
+#include "xf86drm.h"
+
+static void print(void* list)
+{
+    unsigned long key;
+    void          *value;
+
+    if (drmSLFirst(list, &key, &value)) {
+	do {
+	    printf("key = %5lu, value = %p\n", key, value);
+	} while (drmSLNext(list, &key, &value));
+    }
+}
+
+static double do_time(int size, int iter)
+{
+    void           *list;
+    int            i, j;
+    unsigned long  keys[1000000];
+    unsigned long  previous;
+    unsigned long  key;
+    void           *value;
+    struct timeval start, stop;
+    double         usec;
+    void           *ranstate;
+
+    list = drmSLCreate();
+    ranstate = drmRandomCreate(12345);
+
+    for (i = 0; i < size; i++) {
+	keys[i] = drmRandom(ranstate);
+	drmSLInsert(list, keys[i], NULL);
+    }
+
+    previous = 0;
+    if (drmSLFirst(list, &key, &value)) {
+	do {
+	    if (key <= previous) {
+		printf( "%lu !< %lu\n", previous, key);
+	    }
+	    previous = key;
+	} while (drmSLNext(list, &key, &value));
+    }
+
+    gettimeofday(&start, NULL);
+    for (j = 0; j < iter; j++) {
+	for (i = 0; i < size; i++) {
+	    if (drmSLLookup(list, keys[i], &value))
+		printf("Error %lu %d\n", keys[i], i);
+	}
+    }
+    gettimeofday(&stop, NULL);
+
+    usec = (double)(stop.tv_sec * 1000000 + stop.tv_usec
+		    - start.tv_sec * 1000000 - start.tv_usec) / (size * iter);
+
+    printf("%0.2f microseconds for list length %d\n", usec, size);
+
+    drmRandomDouble(ranstate);
+    drmSLDestroy(list);
+
+    return usec;
+}
+
+static void print_neighbors(void *list, unsigned long key,
+                            unsigned long expected_prev,
+                            unsigned long expected_next)
+{
+    unsigned long prev_key = 0;
+    unsigned long next_key = 0;
+    void          *prev_value;
+    void          *next_value;
+    int           retval;
+
+    retval = drmSLLookupNeighbors(list, key,
+				  &prev_key, &prev_value,
+				  &next_key, &next_value);
+    printf("Neighbors of %5lu: %d %5lu %5lu\n",
+	   key, retval, prev_key, next_key);
+    if (prev_key != expected_prev) {
+        fprintf(stderr, "Unexpected neighbor: %5lu. Expected: %5lu\n",
+                prev_key, expected_prev);
+	exit(1);
+    }
+    if (next_key != expected_next) {
+        fprintf(stderr, "Unexpected neighbor: %5lu. Expected: %5lu\n",
+                next_key, expected_next);
+	exit(1);
+    }
+}
+
+int main(void)
+{
+    void*    list;
+    double   usec, usec2, usec3, usec4;
+
+    list = drmSLCreate();
+    printf( "list at %p\n", list);
+
+    print(list);
+    printf("\n==============================\n\n");
+
+    drmSLInsert(list, 123, NULL);
+    drmSLInsert(list, 213, NULL);
+    drmSLInsert(list, 50, NULL);
+    print(list);
+    printf("\n==============================\n\n");
+
+    print_neighbors(list, 0, 0, 50);
+    print_neighbors(list, 50, 0, 50);
+    print_neighbors(list, 51, 50, 123);
+    print_neighbors(list, 123, 50, 123);
+    print_neighbors(list, 200, 123, 213);
+    print_neighbors(list, 213, 123, 213);
+    print_neighbors(list, 256, 213, 256);
+    printf("\n==============================\n\n");
+
+    drmSLDelete(list, 50);
+    print(list);
+    printf("\n==============================\n\n");
+
+    drmSLDump(list);
+    drmSLDestroy(list);
+    printf("\n==============================\n\n");
+
+    usec  = do_time(100, 10000);
+    usec2 = do_time(1000, 500);
+    printf("Table size increased by %0.2f, search time increased by %0.2f\n",
+	   1000.0/100.0, usec2 / usec);
+
+    usec3 = do_time(10000, 50);
+    printf("Table size increased by %0.2f, search time increased by %0.2f\n",
+	   10000.0/100.0, usec3 / usec);
+
+    usec4 = do_time(100000, 4);
+    printf("Table size increased by %0.2f, search time increased by %0.2f\n",
+	   100000.0/100.0, usec4 / usec);
+
+    return 0;
+}