From 4f57abfe66091281c9f59c14e6ea27b524b55d5b Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Kristian=20H=C3=B8gsberg?= Date: Tue, 17 Nov 2009 11:14:54 -0500 Subject: Move libdrm/ up one level --- libdrm/xf86drmHash.c | 428 --------------------------------------------------- 1 file changed, 428 deletions(-) delete mode 100644 libdrm/xf86drmHash.c (limited to 'libdrm/xf86drmHash.c') diff --git a/libdrm/xf86drmHash.c b/libdrm/xf86drmHash.c deleted file mode 100644 index 82cbc2a5..00000000 --- a/libdrm/xf86drmHash.c +++ /dev/null @@ -1,428 +0,0 @@ -/* 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 - * - * 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 -#include - -#define HASH_MAIN 0 - -#if !HASH_MAIN -# include "xf86drm.h" -#endif - -#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) -{ - unsigned long hash = 0; - unsigned long tmp = key; - static int init = 0; - static unsigned long scatter[256]; - int i; - - if (!init) { - HASH_RANDOM_DECL; - HASH_RANDOM_INIT(37); - for (i = 0; i < 256; i++) scatter[i] = HASH_RANDOM; - HASH_RANDOM_DESTROY; - ++init; - } - - while (tmp) { - hash = (hash << 1) + scatter[tmp & 0xff]; - tmp >>= 8; - } - - hash %= HASH_SIZE; -#if HASH_DEBUG - printf( "Hash(%d) = %d\n", key, hash); -#endif - return hash; -} - -void *drmHashCreate(void) -{ - HashTablePtr table; - int i; - - table = HASH_ALLOC(sizeof(*table)); - if (!table) return NULL; - table->magic = HASH_MAGIC; - table->entries = 0; - table->hits = 0; - table->partials = 0; - table->misses = 0; - - for (i = 0; i < HASH_SIZE; i++) table->buckets[i] = NULL; - return table; -} - -int drmHashDestroy(void *t) -{ - HashTablePtr table = (HashTablePtr)t; - HashBucketPtr bucket; - HashBucketPtr next; - int i; - - if (table->magic != HASH_MAGIC) return -1; /* Bad magic */ - - for (i = 0; i < HASH_SIZE; i++) { - for (bucket = table->buckets[i]; bucket;) { - next = bucket->next; - HASH_FREE(bucket); - bucket = next; - } - } - HASH_FREE(table); - return 0; -} - -/* Find the bucket and organize the list so that this bucket is at the - top. */ - -static HashBucketPtr HashFind(HashTablePtr table, - unsigned long key, unsigned long *h) -{ - unsigned long hash = HashHash(key); - HashBucketPtr prev = NULL; - HashBucketPtr bucket; - - if (h) *h = hash; - - for (bucket = table->buckets[hash]; bucket; bucket = bucket->next) { - if (bucket->key == key) { - if (prev) { - /* Organize */ - prev->next = bucket->next; - bucket->next = table->buckets[hash]; - table->buckets[hash] = bucket; - ++table->partials; - } else { - ++table->hits; - } - return bucket; - } - prev = bucket; - } - ++table->misses; - return NULL; -} - -int drmHashLookup(void *t, unsigned long key, void **value) -{ - HashTablePtr table = (HashTablePtr)t; - HashBucketPtr bucket; - - if (!table || table->magic != HASH_MAGIC) return -1; /* Bad magic */ - - bucket = HashFind(table, key, NULL); - if (!bucket) return 1; /* Not found */ - *value = bucket->value; - return 0; /* Found */ -} - -int drmHashInsert(void *t, unsigned long key, void *value) -{ - HashTablePtr table = (HashTablePtr)t; - HashBucketPtr bucket; - unsigned long hash; - - if (table->magic != HASH_MAGIC) return -1; /* Bad magic */ - - if (HashFind(table, key, &hash)) return 1; /* Already in table */ - - bucket = HASH_ALLOC(sizeof(*bucket)); - if (!bucket) return -1; /* Error */ - bucket->key = key; - bucket->value = value; - bucket->next = table->buckets[hash]; - table->buckets[hash] = bucket; -#if HASH_DEBUG - printf("Inserted %d at %d/%p\n", key, hash, bucket); -#endif - return 0; /* Added to table */ -} - -int drmHashDelete(void *t, unsigned long key) -{ - HashTablePtr table = (HashTablePtr)t; - unsigned long hash; - HashBucketPtr bucket; - - if (table->magic != HASH_MAGIC) return -1; /* Bad magic */ - - bucket = HashFind(table, key, &hash); - - if (!bucket) return 1; /* Not found */ - - table->buckets[hash] = bucket->next; - HASH_FREE(bucket); - return 0; -} - -int drmHashNext(void *t, unsigned long *key, void **value) -{ - HashTablePtr table = (HashTablePtr)t; - - while (table->p0 < HASH_SIZE) { - if (table->p1) { - *key = table->p1->key; - *value = table->p1->value; - table->p1 = table->p1->next; - return 1; - } - table->p1 = table->buckets[table->p0]; - ++table->p0; - } - return 0; -} - -int drmHashFirst(void *t, unsigned long *key, void **value) -{ - HashTablePtr table = (HashTablePtr)t; - - if (table->magic != HASH_MAGIC) return -1; /* Bad magic */ - - table->p0 = 0; - 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 -- cgit v1.2.3