+++ /dev/null
-/**
- * \file hash.c
- * Generic hash table.
- *
- * This code taken from Mesa and adapted.
- */
-
-#include <assert.h>
-#include <stdlib.h>
-#include <stdio.h>
-#include "eglhash.h"
-
-
-#define TABLE_SIZE 1023 /**< Size of lookup table/array */
-
-#define HASH_FUNC(K) ((K) % TABLE_SIZE)
-
-
-/*
- * Unfinished mutex stuff
- */
-
-typedef int _EGLMutex;
-
-static void
-_eglInitMutex(_EGLMutex m)
-{
-}
-
-static void
-_eglDestroyMutex(_EGLMutex m)
-{
-}
-
-static void
-_eglLockMutex(_EGLMutex m)
-{
-}
-
-static void
-_eglUnlockMutex(_EGLMutex m)
-{
-}
-
-
-
-typedef struct _egl_hashentry _EGLHashentry;
-
-struct _egl_hashentry
-{
- EGLuint Key; /**< the entry's key */
- void *Data; /**< the entry's data */
- _EGLHashentry *Next; /**< pointer to next entry */
-};
-
-
-struct _egl_hashtable
-{
- _EGLHashentry *Table[TABLE_SIZE]; /**< the lookup table */
- EGLuint MaxKey; /**< highest key inserted so far */
- _EGLMutex Mutex; /**< mutual exclusion lock */
-};
-
-
-/**
- * Create a new hash table.
- *
- * \return pointer to a new, empty hash table.
- */
-_EGLHashtable *
-_eglNewHashTable(void)
-{
- _EGLHashtable *table = (_EGLHashtable *) calloc(1, sizeof(_EGLHashtable));
- if (table) {
- _eglInitMutex(table->Mutex);
- table->MaxKey = 1;
- }
- return table;
-}
-
-
-
-/**
- * Delete a hash table.
- * Frees each entry on the hash table and then the hash table structure itself.
- * Note that the caller should have already traversed the table and deleted
- * the objects in the table (i.e. We don't free the entries' data pointer).
- *
- * \param table the hash table to delete.
- */
-void
-_eglDeleteHashTable(_EGLHashtable *table)
-{
- EGLuint i;
- assert(table);
- for (i = 0; i < TABLE_SIZE; i++) {
- _EGLHashentry *entry = table->Table[i];
- while (entry) {
- _EGLHashentry *next = entry->Next;
- free(entry);
- entry = next;
- }
- }
- _eglDestroyMutex(table->Mutex);
- free(table);
-}
-
-
-
-/**
- * Lookup an entry in the hash table.
- *
- * \param table the hash table.
- * \param key the key.
- *
- * \return pointer to user's data or NULL if key not in table
- */
-void *
-_eglHashLookup(const _EGLHashtable *table, EGLuint key)
-{
- EGLuint pos;
- const _EGLHashentry *entry;
-
- assert(table);
-
- if (!key)
- return NULL;
-
- pos = HASH_FUNC(key);
- entry = table->Table[pos];
- while (entry) {
- if (entry->Key == key) {
- return entry->Data;
- }
- entry = entry->Next;
- }
- return NULL;
-}
-
-
-
-/**
- * Insert a key/pointer pair into the hash table.
- * If an entry with this key already exists we'll replace the existing entry.
- *
- * \param table the hash table.
- * \param key the key (not zero).
- * \param data pointer to user data.
- */
-void
-_eglHashInsert(_EGLHashtable *table, EGLuint key, void *data)
-{
- /* search for existing entry with this key */
- EGLuint pos;
- _EGLHashentry *entry;
-
- assert(table);
- assert(key);
-
- _eglLockMutex(table->Mutex);
-
- if (key > table->MaxKey)
- table->MaxKey = key;
-
- pos = HASH_FUNC(key);
- entry = table->Table[pos];
- while (entry) {
- if (entry->Key == key) {
- /* replace entry's data */
- entry->Data = data;
- _eglUnlockMutex(table->Mutex);
- return;
- }
- entry = entry->Next;
- }
-
- /* alloc and insert new table entry */
- entry = (_EGLHashentry *) malloc(sizeof(_EGLHashentry));
- entry->Key = key;
- entry->Data = data;
- entry->Next = table->Table[pos];
- table->Table[pos] = entry;
-
- _eglUnlockMutex(table->Mutex);
-}
-
-
-
-/**
- * Remove an entry from the hash table.
- *
- * \param table the hash table.
- * \param key key of entry to remove.
- *
- * While holding the hash table's lock, searches the entry with the matching
- * key and unlinks it.
- */
-void
-_eglHashRemove(_EGLHashtable *table, EGLuint key)
-{
- EGLuint pos;
- _EGLHashentry *entry, *prev;
-
- assert(table);
- assert(key);
-
- _eglLockMutex(table->Mutex);
-
- pos = HASH_FUNC(key);
- prev = NULL;
- entry = table->Table[pos];
- while (entry) {
- if (entry->Key == key) {
- /* found it! */
- if (prev) {
- prev->Next = entry->Next;
- }
- else {
- table->Table[pos] = entry->Next;
- }
- free(entry);
- _eglUnlockMutex(table->Mutex);
- return;
- }
- prev = entry;
- entry = entry->Next;
- }
-
- _eglUnlockMutex(table->Mutex);
-}
-
-
-
-/**
- * Get the key of the "first" entry in the hash table.
- *
- * This is used in the course of deleting all display lists when
- * a context is destroyed.
- *
- * \param table the hash table
- *
- * \return key for the "first" entry in the hash table.
- *
- * While holding the lock, walks through all table positions until finding
- * the first entry of the first non-empty one.
- */
-EGLuint
-_eglHashFirstEntry(_EGLHashtable *table)
-{
- EGLuint pos;
- assert(table);
- _eglLockMutex(table->Mutex);
- for (pos = 0; pos < TABLE_SIZE; pos++) {
- if (table->Table[pos]) {
- _eglUnlockMutex(table->Mutex);
- return table->Table[pos]->Key;
- }
- }
- _eglUnlockMutex(table->Mutex);
- return 0;
-}
-
-
-/**
- * Given a hash table key, return the next key. This is used to walk
- * over all entries in the table. Note that the keys returned during
- * walking won't be in any particular order.
- * \return next hash key or 0 if end of table.
- */
-EGLuint
-_eglHashNextEntry(const _EGLHashtable *table, EGLuint key)
-{
- const _EGLHashentry *entry;
- EGLuint pos;
-
- assert(table);
- assert(key);
-
- /* Find the entry with given key */
- pos = HASH_FUNC(key);
- entry = table->Table[pos];
- while (entry) {
- if (entry->Key == key) {
- break;
- }
- entry = entry->Next;
- }
-
- if (!entry) {
- /* the key was not found, we can't find next entry */
- return 0;
- }
-
- if (entry->Next) {
- /* return next in linked list */
- return entry->Next->Key;
- }
- else {
- /* look for next non-empty table slot */
- pos++;
- while (pos < TABLE_SIZE) {
- if (table->Table[pos]) {
- return table->Table[pos]->Key;
- }
- pos++;
- }
- return 0;
- }
-}
-
-
-/**
- * Dump contents of hash table for debugging.
- *
- * \param table the hash table.
- */
-void
-_eglHashPrint(const _EGLHashtable *table)
-{
- EGLuint i;
- assert(table);
- for (i = 0; i < TABLE_SIZE; i++) {
- const _EGLHashentry *entry = table->Table[i];
- while (entry) {
- printf("%u %p\n", entry->Key, entry->Data);
- entry = entry->Next;
- }
- }
-}
-
-
-
-/**
- * Return a new, unused hash key.
- */
-EGLuint
-_eglHashGenKey(_EGLHashtable *table)
-{
- EGLuint k;
-
- _eglLockMutex(table->Mutex);
- k = table->MaxKey;
- table->MaxKey++;
- _eglUnlockMutex(table->Mutex);
- return k;
-}
-
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