OpenTTD-patches/queue.c
2005-12-14 06:20:23 +00:00

724 lines
17 KiB
C

/* $Id$ */
#include "stdafx.h"
#include "openttd.h"
#include "queue.h"
static void Stack_Clear(Queue* q, bool free_values)
{
uint i;
if (free_values)
for (i=0;i<q->data.stack.size;i++)
free(q->data.stack.elements[i]);
q->data.stack.size = 0;
}
static void Stack_Free(Queue* q, bool free_values)
{
q->clear(q, free_values);
free(q->data.stack.elements);
if (q->freeq)
free(q);
}
static bool Stack_Push(Queue* q, void* item, int priority)
{
if (q->data.stack.size == q->data.stack.max_size)
return false;
q->data.stack.elements[q->data.stack.size++] = item;
return true;
}
static void* Stack_Pop(Queue* q)
{
void* result;
if (q->data.stack.size == 0)
return NULL;
result = q->data.stack.elements[--q->data.stack.size];
return result;
}
static bool Stack_Delete(Queue* q, void* item, int priority)
{
return false;
}
static Queue* init_stack(Queue* q, uint max_size)
{
q->push = Stack_Push;
q->pop = Stack_Pop;
q->del = Stack_Delete;
q->clear = Stack_Clear;
q->free = Stack_Free;
q->data.stack.max_size = max_size;
q->data.stack.size = 0;
q->data.stack.elements = malloc(max_size * sizeof(void*));
q->freeq = false;
return q;
}
Queue* new_Stack(uint max_size)
{
Queue* q = malloc(sizeof(Queue));
init_stack(q, max_size);
q->freeq = true;
return q;
}
/*
* Fifo
*/
static void Fifo_Clear(Queue* q, bool free_values)
{
uint head, tail;
if (free_values) {
head = q->data.fifo.head;
tail = q->data.fifo.tail; /* cache for speed */
while (head != tail) {
free(q->data.fifo.elements[tail]);
tail = (tail + 1) % q->data.fifo.max_size;
}
}
q->data.fifo.head = q->data.fifo.tail = 0;
}
static void Fifo_Free(Queue* q, bool free_values)
{
q->clear(q, free_values);
free(q->data.fifo.elements);
if (q->freeq)
free(q);
}
static bool Fifo_Push(Queue* q, void* item, int priority)
{
uint next = (q->data.fifo.head + 1) % q->data.fifo.max_size;
if (next == q->data.fifo.tail)
return false;
q->data.fifo.elements[q->data.fifo.head] = item;
q->data.fifo.head = next;
return true;
}
static void* Fifo_Pop(Queue* q)
{
void* result;
if (q->data.fifo.head == q->data.fifo.tail)
return NULL;
result = q->data.fifo.elements[q->data.fifo.tail];
q->data.fifo.tail = (q->data.fifo.tail + 1) % q->data.fifo.max_size;
return result;
}
static bool Fifo_Delete(Queue* q, void* item, int priority)
{
return false;
}
static Queue* init_fifo(Queue* q, uint max_size)
{
q->push = Fifo_Push;
q->pop = Fifo_Pop;
q->del = Fifo_Delete;
q->clear = Fifo_Clear;
q->free = Fifo_Free;
q->data.fifo.max_size = max_size;
q->data.fifo.head = 0;
q->data.fifo.tail = 0;
q->data.fifo.elements = malloc(max_size * sizeof(void*));
q->freeq = false;
return q;
}
Queue* new_Fifo(uint max_size)
{
Queue* q = malloc(sizeof(Queue));
init_fifo(q, max_size);
q->freeq = true;
return q;
}
/*
* Insertion Sorter
*/
static void InsSort_Clear(Queue* q, bool free_values)
{
InsSortNode* node = q->data.inssort.first;
InsSortNode* prev;
while (node != NULL) {
if (free_values)
free(node->item);
prev = node;
node = node->next;
free(prev);
}
q->data.inssort.first = NULL;
}
static void InsSort_Free(Queue* q, bool free_values)
{
q->clear(q, free_values);
if (q->freeq)
free(q);
}
static bool InsSort_Push(Queue* q, void* item, int priority)
{
InsSortNode* newnode = malloc(sizeof(InsSortNode));
if (newnode == NULL) return false;
newnode->item = item;
newnode->priority = priority;
if (q->data.inssort.first == NULL || q->data.inssort.first->priority >= priority) {
newnode->next = q->data.inssort.first;
q->data.inssort.first = newnode;
} else {
InsSortNode* node = q->data.inssort.first;
while( node != NULL ) {
if (node->next == NULL || node->next->priority >= priority) {
newnode->next = node->next;
node->next = newnode;
break;
}
node = node->next;
}
}
return true;
}
static void* InsSort_Pop(Queue* q)
{
InsSortNode* node = q->data.inssort.first;
void* result;
if (node == NULL)
return NULL;
result = node->item;
q->data.inssort.first = q->data.inssort.first->next;
if (q->data.inssort.first)
assert(q->data.inssort.first->priority >= node->priority);
free(node);
return result;
}
static bool InsSort_Delete(Queue* q, void* item, int priority)
{
return false;
}
void init_InsSort(Queue* q) {
q->push = InsSort_Push;
q->pop = InsSort_Pop;
q->del = InsSort_Delete;
q->clear = InsSort_Clear;
q->free = InsSort_Free;
q->data.inssort.first = NULL;
q->freeq = false;
}
Queue* new_InsSort(void)
{
Queue* q = malloc(sizeof(Queue));
init_InsSort(q);
q->freeq = true;
return q;
}
/*
* Binary Heap
* For information, see: http://www.policyalmanac.org/games/binaryHeaps.htm
*/
#define BINARY_HEAP_BLOCKSIZE (1 << BINARY_HEAP_BLOCKSIZE_BITS)
#define BINARY_HEAP_BLOCKSIZE_MASK (BINARY_HEAP_BLOCKSIZE-1)
// To make our life easy, we make the next define
// Because Binary Heaps works with array from 1 to n,
// and C with array from 0 to n-1, and we don't like typing
// q->data.binaryheap.elements[i-1] every time, we use this define.
#define BIN_HEAP_ARR(i) q->data.binaryheap.elements[((i)-1) >> BINARY_HEAP_BLOCKSIZE_BITS][((i)-1) & BINARY_HEAP_BLOCKSIZE_MASK]
static void BinaryHeap_Clear(Queue* q, bool free_values)
{
/* Free all items if needed and free all but the first blocks of
* memory */
uint i,j;
for (i=0;i<q->data.binaryheap.blocks;i++) {
if (q->data.binaryheap.elements[i] == NULL) {
/* No more allocated blocks */
break;
}
/* For every allocated block */
if (free_values)
for (j=0;j<(1<<BINARY_HEAP_BLOCKSIZE_BITS);j++) {
/* For every element in the block */
if ((q->data.binaryheap.size >> BINARY_HEAP_BLOCKSIZE_BITS) == i
&& (q->data.binaryheap.size & BINARY_HEAP_BLOCKSIZE_MASK) == j)
break; /* We're past the last element */
free(q->data.binaryheap.elements[i][j].item);
}
if (i != 0) {
/* Leave the first block of memory alone */
free(q->data.binaryheap.elements[i]);
q->data.binaryheap.elements[i] = NULL;
}
}
q->data.binaryheap.size = 0;
q->data.binaryheap.blocks = 1;
}
static void BinaryHeap_Free(Queue* q, bool free_values)
{
uint i;
q->clear(q, free_values);
for (i=0;i<q->data.binaryheap.blocks;i++) {
if (q->data.binaryheap.elements[i] == NULL)
break;
free(q->data.binaryheap.elements[i]);
}
if (q->freeq)
free(q);
}
static bool BinaryHeap_Push(Queue* q, void* item, int priority)
{
#ifdef QUEUE_DEBUG
printf("[BinaryHeap] Pushing an element. There are %d elements left\n", q->data.binaryheap.size);
#endif
if (q->data.binaryheap.size == q->data.binaryheap.max_size)
return false;
assert(q->data.binaryheap.size < q->data.binaryheap.max_size);
if (q->data.binaryheap.elements[q->data.binaryheap.size >> BINARY_HEAP_BLOCKSIZE_BITS] == NULL) {
/* The currently allocated blocks are full, allocate a new one */
assert((q->data.binaryheap.size & BINARY_HEAP_BLOCKSIZE_MASK) == 0);
q->data.binaryheap.elements[q->data.binaryheap.size >> BINARY_HEAP_BLOCKSIZE_BITS] = malloc(BINARY_HEAP_BLOCKSIZE * sizeof(BinaryHeapNode));
q->data.binaryheap.blocks++;
#ifdef QUEUE_DEBUG
printf("[BinaryHeap] Increasing size of elements to %d nodes\n",q->data.binaryheap.blocks * BINARY_HEAP_BLOCKSIZE);
#endif
}
// Add the item at the end of the array
BIN_HEAP_ARR(q->data.binaryheap.size+1).priority = priority;
BIN_HEAP_ARR(q->data.binaryheap.size+1).item = item;
q->data.binaryheap.size++;
// Now we are going to check where it belongs. As long as the parent is
// bigger, we switch with the parent
{
int i, j;
BinaryHeapNode temp;
i = q->data.binaryheap.size;
while (i > 1) {
// Get the parent of this object (divide by 2)
j = i / 2;
// Is the parent bigger then the current, switch them
if (BIN_HEAP_ARR(i).priority <= BIN_HEAP_ARR(j).priority) {
temp = BIN_HEAP_ARR(j);
BIN_HEAP_ARR(j) = BIN_HEAP_ARR(i);
BIN_HEAP_ARR(i) = temp;
i = j;
} else {
// It is not, we're done!
break;
}
}
}
return true;
}
static bool BinaryHeap_Delete(Queue* q, void* item, int priority)
{
#ifdef QUEUE_DEBUG
printf("[BinaryHeap] Deleting an element. There are %d elements left\n", q->data.binaryheap.size);
#endif
uint i = 0;
// First, we try to find the item..
do {
if (BIN_HEAP_ARR(i+1).item == item) break;
i++;
} while (i < q->data.binaryheap.size);
// We did not find the item, so we return false
if (i == q->data.binaryheap.size) return false;
// Now we put the last item over the current item while decreasing the size of the elements
q->data.binaryheap.size--;
BIN_HEAP_ARR(i+1) = BIN_HEAP_ARR(q->data.binaryheap.size+1);
// Now the only thing we have to do, is resort it..
// On place i there is the item to be sorted.. let's start there
{
uint j;
BinaryHeapNode temp;
// Because of the fast that Binary Heap uses array from 1 to n, we need to increase
// i with 1
i++;
for (;;) {
j = i;
// Check if we have 2 childs
if (2*j+1 <= q->data.binaryheap.size) {
// Is this child smaller than the parent?
if (BIN_HEAP_ARR(j).priority >= BIN_HEAP_ARR(2*j).priority) {i = 2*j; }
// Yes, we _need_ to use i here, not j, because we want to have the smallest child
// This way we get that straight away!
if (BIN_HEAP_ARR(i).priority >= BIN_HEAP_ARR(2*j+1).priority) { i = 2*j+1; }
// Do we have one child?
} else if (2*j <= q->data.binaryheap.size) {
if (BIN_HEAP_ARR(j).priority >= BIN_HEAP_ARR(2*j).priority) { i = 2*j; }
}
// One of our childs is smaller than we are, switch
if (i != j) {
temp = BIN_HEAP_ARR(j);
BIN_HEAP_ARR(j) = BIN_HEAP_ARR(i);
BIN_HEAP_ARR(i) = temp;
} else {
// None of our childs is smaller, so we stay here.. stop :)
break;
}
}
}
return true;
}
static void* BinaryHeap_Pop(Queue* q)
{
#ifdef QUEUE_DEBUG
printf("[BinaryHeap] Popping an element. There are %d elements left\n", q->data.binaryheap.size);
#endif
void* result;
if (q->data.binaryheap.size == 0)
return NULL;
// The best item is always on top, so give that as result
result = BIN_HEAP_ARR(1).item;
// And now we should get ride of this item...
BinaryHeap_Delete(q,BIN_HEAP_ARR(1).item, BIN_HEAP_ARR(1).priority);
return result;
}
void init_BinaryHeap(Queue* q, uint max_size)
{
assert(q);
q->push = BinaryHeap_Push;
q->pop = BinaryHeap_Pop;
q->del = BinaryHeap_Delete;
q->clear = BinaryHeap_Clear;
q->free = BinaryHeap_Free;
q->data.binaryheap.max_size = max_size;
q->data.binaryheap.size = 0;
// We malloc memory in block of BINARY_HEAP_BLOCKSIZE
// It autosizes when it runs out of memory
q->data.binaryheap.elements = calloc(1, ((max_size - 1) / BINARY_HEAP_BLOCKSIZE*sizeof(BinaryHeapNode)) + 1);
q->data.binaryheap.elements[0] = malloc(BINARY_HEAP_BLOCKSIZE * sizeof(BinaryHeapNode));
q->data.binaryheap.blocks = 1;
q->freeq = false;
#ifdef QUEUE_DEBUG
printf("[BinaryHeap] Initial size of elements is %d nodes\n",(1024));
#endif
}
Queue* new_BinaryHeap(uint max_size) {
Queue* q = malloc(sizeof(Queue));
init_BinaryHeap(q, max_size);
q->freeq = true;
return q;
}
// Because we don't want anyone else to bother with our defines
#undef BIN_HEAP_ARR
/*
* Hash
*/
void init_Hash(Hash* h, Hash_HashProc* hash, uint num_buckets) {
/* Allocate space for the Hash, the buckets and the bucket flags */
uint i;
assert(h);
#ifdef HASH_DEBUG
debug("Allocated hash: %p", h);
#endif
h->hash = hash;
h->size = 0;
h->num_buckets = num_buckets;
h->buckets = malloc(num_buckets * (sizeof(HashNode) + sizeof(bool)));
#ifdef HASH_DEBUG
debug("Buckets = %p", h->buckets);
#endif
h->buckets_in_use = (bool*)(h->buckets + num_buckets);
h->freeh = false;
for (i=0;i<num_buckets;i++)
h->buckets_in_use[i] = false;
}
Hash* new_Hash(Hash_HashProc* hash, int num_buckets) {
Hash* h = malloc(sizeof(Hash));
init_Hash(h, hash, num_buckets);
h->freeh = true;
return h;
}
void delete_Hash(Hash* h, bool free_values) {
uint i;
/* Iterate all buckets */
for (i=0;i<h->num_buckets;i++)
{
if (h->buckets_in_use[i]) {
HashNode* node;
/* Free the first value */
if (free_values)
free(h->buckets[i].value);
node = h->buckets[i].next;
while (node != NULL) {
HashNode* prev = node;
node = node->next;
/* Free the value */
if (free_values)
free(prev->value);
/* Free the node */
free(prev);
}
}
}
free(h->buckets);
/* No need to free buckets_in_use, it is always allocated in one
* malloc with buckets */
#ifdef HASH_DEBUG
debug("Freeing Hash: %p", h);
#endif
if (h->freeh)
free(h);
}
#ifdef HASH_STATS
static void stat_Hash(Hash* h)
{
uint used_buckets = 0;
uint max_collision = 0;
uint max_usage = 0;
uint usage[200];
uint i;
uint collision;
HashNode* node;
for (i=0;i<200;i++) usage[i] = 0;
for (i=0;i<h->num_buckets;i++) {
collision = 0;
if (h->buckets_in_use[i]) {
used_buckets++;
node = &h->buckets[i];
while (node != NULL) {
collision++;
node = node->next;
}
if (collision > max_collision) max_collision = collision;
}
if (collision > 199) collision = 199;
usage[collision]++;
if (collision >0 && usage[collision] >= max_usage) max_usage = usage[collision];
}
printf("---\nHash size: %d\nNodes used: %d\nNon empty buckets: %d\nMax collision: %d\n", h->num_buckets, h->size, used_buckets, max_collision);
printf("{ ");
for (i=0;i<=max_collision;i++)
if (usage[i]) {
printf("%d:%d ", i, usage[i]);
/*
if (i>0){
uint j;
for (j=0;j<(usage[i] * 160 / 800);j++)
printf("#");
}
printf("\n");
*/
}
printf ("}\n");
}
#endif
void clear_Hash(Hash* h, bool free_values)
{
uint i;
HashNode* node;
#ifdef HASH_STATS
if (h->size > 2000)
stat_Hash(h);
#endif
/* Iterate all buckets */
for (i=0;i<h->num_buckets;i++)
{
if (h->buckets_in_use[i]) {
h->buckets_in_use[i] = false;
/* Free the first value */
if (free_values)
free(h->buckets[i].value);
node = h->buckets[i].next;
while (node != NULL) {
HashNode* prev = node;
node = node->next;
if (free_values)
free(prev->value);
free(prev);
}
}
}
h->size = 0;
}
/* Finds the node that that saves this key pair. If it is not
* found, returns NULL. If it is found, *prev is set to the
* node before the one found, or if the node found was the first in the bucket
* to NULL. If it is not found, *prev is set to the last HashNode in the
* bucket, or NULL if it is empty. prev can also be NULL, in which case it is
* not used for output.
*/
static HashNode* Hash_FindNode(Hash* h, uint key1, uint key2, HashNode** prev_out)
{
uint hash = h->hash(key1, key2);
HashNode* result = NULL;
#ifdef HASH_DEBUG
debug("Looking for %u, %u", key1, key2);
#endif
/* Check if the bucket is empty */
if (!h->buckets_in_use[hash]) {
if (prev_out)
*prev_out = NULL;
result = NULL;
/* Check the first node specially */
} else if (h->buckets[hash].key1 == key1 && h->buckets[hash].key2 == key2) {
/* Save the value */
result = h->buckets + hash;
if (prev_out)
*prev_out = NULL;
#ifdef HASH_DEBUG
debug("Found in first node: %p", result);
#endif
/* Check all other nodes */
} else {
HashNode* prev = h->buckets + hash;
HashNode* node = prev->next;
while (node != NULL) {
if (node->key1 == key1 && node->key2 == key2) {
/* Found it */
result = node;
#ifdef HASH_DEBUG
debug("Found in other node: %p", result);
#endif
break;
}
prev = node;
node = node->next;
}
if (prev_out)
*prev_out = prev;
}
#ifdef HASH_DEBUG
if (result == NULL)
debug("Not found");
#endif
return result;
}
void* Hash_Delete(Hash* h, uint key1, uint key2) {
void* result;
HashNode* prev; /* Used as output var for below function call */
HashNode* node = Hash_FindNode(h, key1, key2, &prev);
if (node == NULL) {
/* not found */
result = NULL;
} else if (prev == NULL) {
/* It is in the first node, we can't free that one, so we free
* the next one instead (if there is any)*/
/* Save the value */
result = node->value;
if (node->next != NULL) {
HashNode* next = node->next;
/* Copy the second to the first */
*node = *next;
/* Free the second */
#ifndef NOFREE
free(next);
#endif
} else {
/* This was the last in this bucket */
/* Mark it as empty */
uint hash = h->hash(key1, key2);
h->buckets_in_use[hash] = false;
}
} else {
/* It is in another node */
/* Save the value */
result = node->value;
/* Link previous and next nodes */
prev->next = node->next;
/* Free the node */
#ifndef NOFREE
free(node);
#endif
}
if (result != NULL)
h->size--;
return result;
}
void* Hash_Set(Hash* h, uint key1, uint key2, void* value) {
HashNode* prev;
HashNode* node = Hash_FindNode(h, key1, key2, &prev);
void* result = NULL;
if (node != NULL) {
/* Found it */
result = node->value;
node->value = value;
return result;
}
/* It is not yet present, let's add it */
if (prev == NULL) {
/* The bucket is still empty */
uint hash = h->hash(key1, key2);
h->buckets_in_use[hash] = true;
node = h->buckets + hash;
} else {
/* Add it after prev */
node = malloc(sizeof(HashNode));
prev->next = node;
}
node->next = NULL;
node->key1 = key1;
node->key2 = key2;
node->value = value;
h->size++;
return NULL;
}
void* Hash_Get(Hash* h, uint key1, uint key2) {
HashNode* node = Hash_FindNode(h, key1, key2, NULL);
#ifdef HASH_DEBUG
debug("Found node: %p", node);
#endif
if (node == NULL) {
/* Node not found */
return NULL;
} else {
return node->value;
}
}
uint Hash_Size(Hash* h) {
return h->size;
}