-#define ZONEID 0x1d4a11
-#define MINFRAGMENT 64
-
-typedef struct memblock_s
-{
- int size; // including the header and possibly tiny fragments
- int tag; // a tag of 0 is a free block
- int id; // should be ZONEID
- struct memblock_s *next, *prev;
- int pad; // pad to 64 bit boundary
-} memblock_t;
-
-typedef struct
-{
- int size; // total bytes malloced, including header
- memblock_t blocklist; // start / end cap for linked list
- memblock_t *rover;
-} memzone_t;
-
-void Cache_FreeLow (int new_low_hunk);
-void Cache_FreeHigh (int new_high_hunk);
-
-
-/*
-==============================================================================
-
- ZONE MEMORY ALLOCATION
-
-There is never any space between memblocks, and there will never be two
-contiguous free memblocks.
-
-The rover can be left pointing at a non-empty block
-
-The zone calls are pretty much only used for small strings and structures,
-all big things are allocated on the hunk.
-==============================================================================
-*/
-
-memzone_t *mainzone;
-
-void Z_ClearZone (memzone_t *zone, int size);
-
-
-/*
-========================
-Z_ClearZone
-========================
-*/
-void Z_ClearZone (memzone_t *zone, int size)
-{
- memblock_t *block;
-
-// set the entire zone to one free block
-
- zone->blocklist.next = zone->blocklist.prev = block =
- (memblock_t *)( (byte *)zone + sizeof(memzone_t) );
- zone->blocklist.tag = 1; // in use block
- zone->blocklist.id = 0;
- zone->blocklist.size = 0;
- zone->rover = block;
-
- block->prev = block->next = &zone->blocklist;
- block->tag = 0; // free block
- block->id = ZONEID;
- block->size = size - sizeof(memzone_t);
-}
-
-
-/*
-========================
-Z_Free
-========================
-*/
-void Z_Free (void *ptr)
-{
- memblock_t *block, *other;
-
- if (!ptr)
- Sys_Error ("Z_Free: NULL pointer");
-
- block = (memblock_t *) ( (byte *)ptr - sizeof(memblock_t));
- if (block->id != ZONEID)
- Sys_Error ("Z_Free: freed a pointer without ZONEID");
- if (block->tag == 0)
- Sys_Error ("Z_Free: freed a freed pointer");
-
- block->tag = 0; // mark as free
-
- other = block->prev;
- if (!other->tag)
- { // merge with previous free block
- other->size += block->size;
- other->next = block->next;
- other->next->prev = other;
- if (block == mainzone->rover)
- mainzone->rover = other;
- block = other;
- }
-
- other = block->next;
- if (!other->tag)
- { // merge the next free block onto the end
- block->size += other->size;
- block->next = other->next;
- block->next->prev = block;
- if (other == mainzone->rover)
- mainzone->rover = block;
- }
-}
-
-
-/*
-========================
-Z_Malloc
-========================
-*/
-void *Z_Malloc (int size)
-{
- void *buf;
-
-Z_CheckHeap (); // DEBUG
- buf = Z_TagMalloc (size, 1);
- if (!buf)
- Sys_Error ("Z_Malloc: failed on allocation of %i bytes",size);
- memset (buf, 0, size);
-
- return buf;
-}
-
-void *Z_TagMalloc (int size, int tag)
-{
- int extra;
- memblock_t *start, *rover, *new, *base;
-
- if (!tag)
- Sys_Error ("Z_TagMalloc: tried to use a 0 tag");
-
-//
-// scan through the block list looking for the first free block
-// of sufficient size
-//
- size += sizeof(memblock_t); // account for size of block header
- size += 4; // space for memory trash tester
- size = (size + 7) & ~7; // align to 8-byte boundary
-
- base = rover = mainzone->rover;
- start = base->prev;
-
- do
- {
- if (rover == start) // scaned all the way around the list
- return NULL;
- if (rover->tag)
- base = rover = rover->next;
- else
- rover = rover->next;
- } while (base->tag || base->size < size);
-
-//
-// found a block big enough
-//
- extra = base->size - size;
- if (extra > MINFRAGMENT)
- { // there will be a free fragment after the allocated block
- new = (memblock_t *) ((byte *)base + size );
- new->size = extra;
- new->tag = 0; // free block
- new->prev = base;
- new->id = ZONEID;
- new->next = base->next;
- new->next->prev = new;
- base->next = new;
- base->size = size;
- }
-
- base->tag = tag; // no longer a free block
-
- mainzone->rover = base->next; // next allocation will start looking here
-
- base->id = ZONEID;
-
-// marker for memory trash testing
- *(int *)((byte *)base + base->size - 4) = ZONEID;
-
- return (void *) ((byte *)base + sizeof(memblock_t));
-}
-
-
-/*
-========================
-Z_Print
-========================
-*/
-void Z_Print (memzone_t *zone)
-{
- memblock_t *block;
-
- Con_Printf ("zone size: %i location: %p\n",mainzone->size,mainzone);
-
- for (block = zone->blocklist.next ; ; block = block->next)
- {
- Con_Printf ("block:%p size:%7i tag:%3i\n",
- block, block->size, block->tag);
-
- if (block->next == &zone->blocklist)
- break; // all blocks have been hit
- if ( (byte *)block + block->size != (byte *)block->next)
- Con_Printf ("ERROR: block size does not touch the next block\n");
- if ( block->next->prev != block)
- Con_Printf ("ERROR: next block doesn't have proper back link\n");
- if (!block->tag && !block->next->tag)
- Con_Printf ("ERROR: two consecutive free blocks\n");
- }
-}
-
-
-/*
-========================
-Z_CheckHeap
-========================
-*/
-void Z_CheckHeap (void)