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/*
* Copyright 1999 Silicon Graphics, Inc.
*/
#include "stdlib.h"
#include "string.h"
#include "arc.h"
typedef struct _Node {
size_t size;
struct _Node *next;
} Node;
static Node *freeList = NULL;
void *malloc(size_t size)
{
Node **free, *mem;
size +=
/* header */ sizeof(Node) + /* round up */ (sizeof(Node) - 1);
size -= size % sizeof(Node);
free = &freeList;
while ((*free != NULL) && ((*free)->size < size))
free = &((*free)->next);
mem = *free;
if (mem != NULL) {
if (mem->size > size) {
Node *split = mem + (size / sizeof(Node));
split->size = mem->size - size;
split->next = mem->next;
mem->size = size;
mem->next = split;
}
*free = mem->next;
mem += 1;
}
return ((void *) mem);
}
void free(void *ptr)
{
if (ptr != NULL) {
Node *mem = ((Node *) ptr) - 1;
Node **free = &freeList;
while ((*free != NULL) && (*free < mem)) {
if (mem ==
(*free + ((*free)->size / sizeof(Node)))) {
(*free)->size += mem->size;
mem = *free;
break;
}
free = &((*free)->next);
}
if (mem != *free) {
mem->next = *free;
*free = mem;
}
if (mem->next == (mem + (mem->size / sizeof(Node)))) {
mem->size += mem->next->size;
mem->next = mem->next->next;
}
}
}
void *realloc(void *ptr, size_t size)
{
if (ptr == NULL) {
ptr = malloc(size);
} else {
Node *mem = ((Node *) ptr) - 1;
size +=
/* header */ sizeof(Node) +
/* round up */ (sizeof(Node) - 1);
size -= size % sizeof(Node);
if (size > mem->size) {
/* Should try to grow */
void *optr = ptr;
ptr = malloc(size);
if (ptr != NULL) {
memcpy(ptr, optr,
mem->size - sizeof(Node));
free(optr);
}
} else if (size < mem->size) {
Node *split = mem + (size / sizeof(Node));
split->size = mem->size - size;
split->next = mem->next;
mem->size = size;
free((void *) (split + 1));
}
}
return ptr;
}
void arclib_malloc_add(ULONG start, ULONG size)
{
Node *node = (Node *) start;
node->size = size - (size % sizeof(Node));
free((void *) (node + 1));
}
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