6 files changed, 260 insertions, 186 deletions

diff --git a/.gitignore b/.gitignore
index cb7128da..f78ad416 100644
--- a/.gitignore
+++ b/.gitignore
@@ -79,6 +79,7 @@ tests/drmstat
 tests/getclient
 tests/getstats
 tests/getversion
+tests/hash
 tests/lock
 tests/openclose
 tests/setversion
diff --git a/Makefile.sources b/Makefile.sources
index 566f7b55..ff4fe5e3 100644
--- a/Makefile.sources
+++ b/Makefile.sources
@@ -1,6 +1,7 @@
 LIBDRM_FILES := \
         xf86drm.c \
         xf86drmHash.c \
+        xf86drmHash.h \
         xf86drmRandom.c \
         xf86drmSL.c \
         xf86drmMode.c \
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 75fc2413..d4674f75 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -29,7 +29,8 @@ LDADD = $(top_builddir)/libdrm.la
 
 check_PROGRAMS = \
         dristat \
-        drmstat
+        drmstat \
+        hash
 
 if HAVE_NOUVEAU
 SUBDIRS += nouveau
diff --git a/tests/hash.c b/tests/hash.c
new file mode 100644
index 00000000..517a667c
--- /dev/null
+++ b/tests/hash.c
@@ -0,0 +1,198 @@
+/* xf86drmHash.c -- Small hash table support for integer -> integer mapping
+ * Created: Sun Apr 18 09:35:45 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 implementation of a fixed-sized
+ * hash table using self-organizing linked lists [Knuth73, pp. 398-399] for
+ * collision resolution.  There are two potentially interesting things
+ * about this implementation:
+ *
+ * 1) The table is power-of-two sized.  Prime sized tables are more
+ * traditional, but do not have a significant advantage over power-of-two
+ * sized table, especially when double hashing is not used for collision
+ * resolution.
+ *
+ * 2) The hash computation uses a table of random integers [Hanson97,
+ * pp. 39-41].
+ *
+ * FUTURE ENHANCEMENTS
+ *
+ * With a table size of 512, the current implementation is sufficient for a
+ * few hundred keys.  Since this is well above the expected size of the
+ * tables for which this implementation was designed, the implementation of
+ * dynamic hash tables was postponed until the need arises.  A common (and
+ * naive) approach to dynamic hash table implementation simply creates a
+ * new hash table when necessary, rehashes all the data into the new table,
+ * and destroys the old table.  The approach in [Larson88] is superior in
+ * two ways: 1) only a portion of the table is expanded when needed,
+ * distributing the expansion cost over several insertions, and 2) portions
+ * of the table can be locked, enabling a scalable thread-safe
+ * implementation.
+ *
+ * REFERENCES
+ *
+ * [Hanson97] David R. Hanson.  C Interfaces and Implementations:
+ * Techniques for Creating Reusable Software.  Reading, Massachusetts:
+ * Addison-Wesley, 1997.
+ *
+ * [Knuth73] Donald E. Knuth. The Art of Computer Programming.  Volume 3:
+ * Sorting and Searching.  Reading, Massachusetts: Addison-Wesley, 1973.
+ *
+ * [Larson88] Per-Ake Larson. "Dynamic Hash Tables".  CACM 31(4), April
+ * 1988, pp. 446-457.
+ *
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "xf86drm.h"
+#include "xf86drmHash.h"
+
+#define DIST_LIMIT 10
+static int dist[DIST_LIMIT];
+
+static void clear_dist(void) {
+    int i;
+
+    for (i = 0; i < DIST_LIMIT; i++) dist[i] = 0;
+}
+
+static int count_entries(HashBucketPtr bucket)
+{
+    int count = 0;
+
+    for (; bucket; bucket = bucket->next) ++count;
+    return count;
+}
+
+static void update_dist(int count)
+{
+    if (count >= DIST_LIMIT) ++dist[DIST_LIMIT-1];
+    else                     ++dist[count];
+}
+
+static void compute_dist(HashTablePtr table)
+{
+    int           i;
+    HashBucketPtr bucket;
+
+    printf("Entries = %ld, hits = %ld, partials = %ld, misses = %ld\n",
+           table->entries, table->hits, table->partials, table->misses);
+    clear_dist();
+    for (i = 0; i < HASH_SIZE; i++) {
+        bucket = table->buckets[i];
+        update_dist(count_entries(bucket));
+    }
+    for (i = 0; i < DIST_LIMIT; i++) {
+        if (i != DIST_LIMIT-1) printf("%5d %10d\n", i, dist[i]);
+        else                   printf("other %10d\n", dist[i]);
+    }
+}
+
+static void check_table(HashTablePtr table,
+                        unsigned long key, unsigned long value)
+{
+    unsigned long retval  = 0;
+    int           retcode = drmHashLookup(table, key, &retval);
+
+    switch (retcode) {
+    case -1:
+        printf("Bad magic = 0x%08lx:"
+               " key = %lu, expected = %lu, returned = %lu\n",
+               table->magic, key, value, retval);
+        break;
+    case 1:
+        printf("Not found: key = %lu, expected = %lu returned = %lu\n",
+               key, value, retval);
+        break;
+    case 0:
+        if (value != retval)
+            printf("Bad value: key = %lu, expected = %lu, returned = %lu\n",
+                   key, value, retval);
+        break;
+    default:
+        printf("Bad retcode = %d: key = %lu, expected = %lu, returned = %lu\n",
+               retcode, key, value, retval);
+        break;
+    }
+}
+
+int main(void)
+{
+    HashTablePtr table;
+    int          i;
+
+    printf("\n***** 256 consecutive integers ****\n");
+    table = drmHashCreate();
+    for (i = 0; i < 256; i++) drmHashInsert(table, i, i);
+    for (i = 0; i < 256; i++) check_table(table, i, i);
+    for (i = 256; i >= 0; i--) check_table(table, i, i);
+    compute_dist(table);
+    drmHashDestroy(table);
+
+    printf("\n***** 1024 consecutive integers ****\n");
+    table = drmHashCreate();
+    for (i = 0; i < 1024; i++) drmHashInsert(table, i, i);
+    for (i = 0; i < 1024; i++) check_table(table, i, i);
+    for (i = 1024; i >= 0; i--) check_table(table, i, i);
+    compute_dist(table);
+    drmHashDestroy(table);
+
+    printf("\n***** 1024 consecutive page addresses (4k pages) ****\n");
+    table = drmHashCreate();
+    for (i = 0; i < 1024; i++) drmHashInsert(table, i*4096, i);
+    for (i = 0; i < 1024; i++) check_table(table, i*4096, i);
+    for (i = 1024; i >= 0; i--) check_table(table, i*4096, i);
+    compute_dist(table);
+    drmHashDestroy(table);
+
+    printf("\n***** 1024 random integers ****\n");
+    table = drmHashCreate();
+    srandom(0xbeefbeef);
+    for (i = 0; i < 1024; i++) drmHashInsert(table, random(), i);
+    srandom(0xbeefbeef);
+    for (i = 0; i < 1024; i++) check_table(table, random(), i);
+    srandom(0xbeefbeef);
+    for (i = 0; i < 1024; i++) check_table(table, random(), i);
+    compute_dist(table);
+    drmHashDestroy(table);
+
+    printf("\n***** 5000 random integers ****\n");
+    table = drmHashCreate();
+    srandom(0xbeefbeef);
+    for (i = 0; i < 5000; i++) drmHashInsert(table, random(), i);
+    srandom(0xbeefbeef);
+    for (i = 0; i < 5000; i++) check_table(table, random(), i);
+    srandom(0xbeefbeef);
+    for (i = 0; i < 5000; i++) check_table(table, random(), i);
+    compute_dist(table);
+    drmHashDestroy(table);
+
+    return 0;
+}
diff --git a/xf86drmHash.c b/xf86drmHash.c
index 82cbc2a5..f7d7f73b 100644
--- a/xf86drmHash.c
+++ b/xf86drmHash.c
@@ -71,60 +71,11 @@
 #include <stdio.h>
 #include <stdlib.h>
 
-#define HASH_MAIN 0
-
-#if !HASH_MAIN
-# include "xf86drm.h"
-#endif
+#include "xf86drm.h"
+#include "xf86drmHash.h"
 
 #define HASH_MAGIC 0xdeadbeef
 #define HASH_DEBUG 0
-#define HASH_SIZE  512          /* Good for about 100 entries */
-                                /* If you change this value, you probably
-                                   have to change the HashHash hashing
-                                   function! */
-
-#if HASH_MAIN
-#define HASH_ALLOC malloc
-#define HASH_FREE  free
-#define HASH_RANDOM_DECL
-#define HASH_RANDOM_INIT(seed)  srandom(seed)
-#define HASH_RANDOM             random()
-#define HASH_RANDOM_DESTROY
-#else
-#define HASH_ALLOC drmMalloc
-#define HASH_FREE  drmFree
-#define HASH_RANDOM_DECL        void *state
-#define HASH_RANDOM_INIT(seed)  state = drmRandomCreate(seed)
-#define HASH_RANDOM             drmRandom(state)
-#define HASH_RANDOM_DESTROY     drmRandomDestroy(state)
-
-#endif
-
-typedef struct HashBucket {
-    unsigned long     key;
-    void              *value;
-    struct HashBucket *next;
-} HashBucket, *HashBucketPtr;
-
-typedef struct HashTable {
-    unsigned long    magic;
-    unsigned long    entries;
-    unsigned long    hits;      /* At top of linked list */
-    unsigned long    partials;  /* Not at top of linked list */
-    unsigned long    misses;    /* Not in table */
-    HashBucketPtr    buckets[HASH_SIZE];
-    int              p0;
-    HashBucketPtr    p1;
-} HashTable, *HashTablePtr;
-
-#if HASH_MAIN
-extern void *drmHashCreate(void);
-extern int  drmHashDestroy(void *t);
-extern int  drmHashLookup(void *t, unsigned long key, unsigned long *value);
-extern int  drmHashInsert(void *t, unsigned long key, unsigned long value);
-extern int  drmHashDelete(void *t, unsigned long key);
-#endif
 
 static unsigned long HashHash(unsigned long key)
 {
@@ -135,10 +86,10 @@ static unsigned long HashHash(unsigned long key)
     int                  i;
 
     if (!init) {
-        HASH_RANDOM_DECL;
-        HASH_RANDOM_INIT(37);
-        for (i = 0; i < 256; i++) scatter[i] = HASH_RANDOM;
-        HASH_RANDOM_DESTROY;
+        void *state;
+        state = drmRandomCreate(37);
+        for (i = 0; i < 256; i++) scatter[i] = drmRandom(state);
+        drmRandomDestroy(state);
         ++init;
     }
 
@@ -159,7 +110,7 @@ void *drmHashCreate(void)
     HashTablePtr table;
     int          i;
 
-    table           = HASH_ALLOC(sizeof(*table));
+    table           = drmMalloc(sizeof(*table));
     if (!table) return NULL;
     table->magic    = HASH_MAGIC;
     table->entries  = 0;
@@ -183,11 +134,11 @@ int drmHashDestroy(void *t)
     for (i = 0; i < HASH_SIZE; i++) {
         for (bucket = table->buckets[i]; bucket;) {
             next = bucket->next;
-            HASH_FREE(bucket);
+            drmFree(bucket);
             bucket = next;
         }
     }
-    HASH_FREE(table);
+    drmFree(table);
     return 0;
 }
 
@@ -245,7 +196,7 @@ int drmHashInsert(void *t, unsigned long key, void *value)
 
     if (HashFind(table, key, &hash)) return 1; /* Already in table */
 
-    bucket               = HASH_ALLOC(sizeof(*bucket));
+    bucket               = drmMalloc(sizeof(*bucket));
     if (!bucket) return -1;     /* Error */
     bucket->key          = key;
     bucket->value        = value;
@@ -270,7 +221,7 @@ int drmHashDelete(void *t, unsigned long key)
     if (!bucket) return 1;      /* Not found */
 
     table->buckets[hash] = bucket->next;
-    HASH_FREE(bucket);
+    drmFree(bucket);
     return 0;
 }
 
@@ -301,128 +252,3 @@ int drmHashFirst(void *t, unsigned long *key, void **value)
     table->p1 = table->buckets[0];
     return drmHashNext(table, key, value);
 }
-
-#if HASH_MAIN
-#define DIST_LIMIT 10
-static int dist[DIST_LIMIT];
-
-static void clear_dist(void) {
-    int i;
-
-    for (i = 0; i < DIST_LIMIT; i++) dist[i] = 0;
-}
-
-static int count_entries(HashBucketPtr bucket)
-{
-    int count = 0;
-
-    for (; bucket; bucket = bucket->next) ++count;
-    return count;
-}
-
-static void update_dist(int count)
-{
-    if (count >= DIST_LIMIT) ++dist[DIST_LIMIT-1];
-    else                     ++dist[count];
-}
-
-static void compute_dist(HashTablePtr table)
-{
-    int           i;
-    HashBucketPtr bucket;
-
-    printf("Entries = %ld, hits = %ld, partials = %ld, misses = %ld\n",
-           table->entries, table->hits, table->partials, table->misses);
-    clear_dist();
-    for (i = 0; i < HASH_SIZE; i++) {
-        bucket = table->buckets[i];
-        update_dist(count_entries(bucket));
-    }
-    for (i = 0; i < DIST_LIMIT; i++) {
-        if (i != DIST_LIMIT-1) printf("%5d %10d\n", i, dist[i]);
-        else                   printf("other %10d\n", dist[i]);
-    }
-}
-
-static void check_table(HashTablePtr table,
-                        unsigned long key, unsigned long value)
-{
-    unsigned long retval  = 0;
-    int           retcode = drmHashLookup(table, key, &retval);
-
-    switch (retcode) {
-    case -1:
-        printf("Bad magic = 0x%08lx:"
-               " key = %lu, expected = %lu, returned = %lu\n",
-               table->magic, key, value, retval);
-        break;
-    case 1:
-        printf("Not found: key = %lu, expected = %lu returned = %lu\n",
-               key, value, retval);
-        break;
-    case 0:
-        if (value != retval)
-            printf("Bad value: key = %lu, expected = %lu, returned = %lu\n",
-                   key, value, retval);
-        break;
-    default:
-        printf("Bad retcode = %d: key = %lu, expected = %lu, returned = %lu\n",
-               retcode, key, value, retval);
-        break;
-    }
-}
-
-int main(void)
-{
-    HashTablePtr table;
-    int          i;
-
-    printf("\n***** 256 consecutive integers ****\n");
-    table = drmHashCreate();
-    for (i = 0; i < 256; i++) drmHashInsert(table, i, i);
-    for (i = 0; i < 256; i++) check_table(table, i, i);
-    for (i = 256; i >= 0; i--) check_table(table, i, i);
-    compute_dist(table);
-    drmHashDestroy(table);
-
-    printf("\n***** 1024 consecutive integers ****\n");
-    table = drmHashCreate();
-    for (i = 0; i < 1024; i++) drmHashInsert(table, i, i);
-    for (i = 0; i < 1024; i++) check_table(table, i, i);
-    for (i = 1024; i >= 0; i--) check_table(table, i, i);
-    compute_dist(table);
-    drmHashDestroy(table);
-
-    printf("\n***** 1024 consecutive page addresses (4k pages) ****\n");
-    table = drmHashCreate();
-    for (i = 0; i < 1024; i++) drmHashInsert(table, i*4096, i);
-    for (i = 0; i < 1024; i++) check_table(table, i*4096, i);
-    for (i = 1024; i >= 0; i--) check_table(table, i*4096, i);
-    compute_dist(table);
-    drmHashDestroy(table);
-
-    printf("\n***** 1024 random integers ****\n");
-    table = drmHashCreate();
-    srandom(0xbeefbeef);
-    for (i = 0; i < 1024; i++) drmHashInsert(table, random(), i);
-    srandom(0xbeefbeef);
-    for (i = 0; i < 1024; i++) check_table(table, random(), i);
-    srandom(0xbeefbeef);
-    for (i = 0; i < 1024; i++) check_table(table, random(), i);
-    compute_dist(table);
-    drmHashDestroy(table);
-
-    printf("\n***** 5000 random integers ****\n");
-    table = drmHashCreate();
-    srandom(0xbeefbeef);
-    for (i = 0; i < 5000; i++) drmHashInsert(table, random(), i);
-    srandom(0xbeefbeef);
-    for (i = 0; i < 5000; i++) check_table(table, random(), i);
-    srandom(0xbeefbeef);
-    for (i = 0; i < 5000; i++) check_table(table, random(), i);
-    compute_dist(table);
-    drmHashDestroy(table);
-
-    return 0;
-}
-#endif
diff --git a/xf86drmHash.h b/xf86drmHash.h
new file mode 100644
index 00000000..38fd84b7
--- /dev/null
+++ b/xf86drmHash.h
@@ -0,0 +1,47 @@
+/*
+ * 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>
+ */
+
+#define HASH_SIZE  512          /* Good for about 100 entries */
+                                /* If you change this value, you probably
+                                   have to change the HashHash hashing
+                                   function! */
+
+typedef struct HashBucket {
+    unsigned long     key;
+    void              *value;
+    struct HashBucket *next;
+} HashBucket, *HashBucketPtr;
+
+typedef struct HashTable {
+    unsigned long    magic;
+    unsigned long    entries;
+    unsigned long    hits;      /* At top of linked list */
+    unsigned long    partials;  /* Not at top of linked list */
+    unsigned long    misses;    /* Not in table */
+    HashBucketPtr    buckets[HASH_SIZE];
+    int              p0;
+    HashBucketPtr    p1;
+} HashTable, *HashTablePtr;