diff options
| author | Paweł Redman <pawel.redman@gmail.com> | 2017-03-22 17:56:34 +0100 |
|---|---|---|
| committer | Paweł Redman <pawel.redman@gmail.com> | 2017-03-22 17:56:34 +0100 |
| commit | 6a777afc079c2a8d3af3ecd2145fe8dd50567a39 (patch) | |
| tree | 520f4489cebf8564ef6cb27064ceea45cbc005b3 /src/cgame/cg_mem.c | |
Diffstat (limited to 'src/cgame/cg_mem.c')
| -rw-r--r-- | src/cgame/cg_mem.c | 202 |
1 files changed, 202 insertions, 0 deletions
diff --git a/src/cgame/cg_mem.c b/src/cgame/cg_mem.c new file mode 100644 index 0000000..7e8b288 --- /dev/null +++ b/src/cgame/cg_mem.c @@ -0,0 +1,202 @@ +/*
+===========================================================================
+Copyright (C) 1999-2005 Id Software, Inc.
+Copyright (C) 2000-2006 Tim Angus
+
+This file is part of Tremulous.
+
+Tremulous is free software; you can redistribute it
+and/or modify it under the terms of the GNU General Public License as
+published by the Free Software Foundation; either version 2 of the License,
+or (at your option) any later version.
+
+Tremulous is distributed in the hope that it will be
+useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with Tremulous; if not, write to the Free Software
+Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+===========================================================================
+*/
+
+#include "cg_local.h"
+
+#define POOLSIZE (256 * 1024)
+#define FREEMEMCOOKIE ((int)0xDEADBE3F) // Any unlikely to be used value
+#define ROUNDBITS 31 // Round to 32 bytes
+
+struct freememnode
+{
+ // Size of ROUNDBITS
+ int cookie, size; // Size includes node (obviously)
+ struct freememnode *prev, *next;
+};
+
+static char memoryPool[ POOLSIZE ];
+static struct freememnode *freehead;
+static int freemem;
+
+void *CG_Alloc( int size )
+{
+ // Find a free block and allocate.
+ // Does two passes, attempts to fill same-sized free slot first.
+
+ struct freememnode *fmn, *prev, *next, *smallest;
+ int allocsize, smallestsize;
+ char *endptr;
+ int *ptr;
+
+ allocsize = ( size + sizeof(int) + ROUNDBITS ) & ~ROUNDBITS; // Round to 32-byte boundary
+ ptr = NULL;
+
+ smallest = NULL;
+ smallestsize = POOLSIZE + 1; // Guaranteed not to miss any slots :)
+ for( fmn = freehead; fmn; fmn = fmn->next )
+ {
+ if( fmn->cookie != FREEMEMCOOKIE )
+ CG_Error( "CG_Alloc: Memory corruption detected!\n" );
+
+ if( fmn->size >= allocsize )
+ {
+ // We've got a block
+ if( fmn->size == allocsize )
+ {
+ // Same size, just remove
+
+ prev = fmn->prev;
+ next = fmn->next;
+ if( prev )
+ prev->next = next; // Point previous node to next
+ if( next )
+ next->prev = prev; // Point next node to previous
+ if( fmn == freehead )
+ freehead = next; // Set head pointer to next
+ ptr = (int *) fmn;
+ break; // Stop the loop, this is fine
+ }
+ else
+ {
+ // Keep track of the smallest free slot
+ if( fmn->size < smallestsize )
+ {
+ smallest = fmn;
+ smallestsize = fmn->size;
+ }
+ }
+ }
+ }
+
+ if( !ptr && smallest )
+ {
+ // We found a slot big enough
+ smallest->size -= allocsize;
+ endptr = (char *) smallest + smallest->size;
+ ptr = (int *) endptr;
+ }
+
+ if( ptr )
+ {
+ freemem -= allocsize;
+ if( cg_debugAlloc.integer )
+ CG_Printf( "CG_Alloc of %i bytes (%i left)\n", allocsize, freemem );
+ memset( ptr, 0, allocsize );
+ *ptr++ = allocsize; // Store a copy of size for deallocation
+ return( (void *) ptr );
+ }
+
+ CG_Error( "CG_Alloc: failed on allocation of %i bytes\n", size );
+ return( NULL );
+}
+
+void CG_Free( void *ptr )
+{
+ // Release allocated memory, add it to the free list.
+
+ struct freememnode *fmn;
+ char *freeend;
+ int *freeptr;
+
+ freeptr = ptr;
+ freeptr--;
+
+ freemem += *freeptr;
+ if( cg_debugAlloc.integer )
+ CG_Printf( "CG_Free of %i bytes (%i left)\n", *freeptr, freemem );
+
+ for( fmn = freehead; fmn; fmn = fmn->next )
+ {
+ freeend = ((char *) fmn) + fmn->size;
+ if( freeend == (char *) freeptr )
+ {
+ // Released block can be merged to an existing node
+
+ fmn->size += *freeptr; // Add size of node.
+ return;
+ }
+ }
+ // No merging, add to head of list
+
+ fmn = (struct freememnode *) freeptr;
+ fmn->size = *freeptr; // Set this first to avoid corrupting *freeptr
+ fmn->cookie = FREEMEMCOOKIE;
+ fmn->prev = NULL;
+ fmn->next = freehead;
+ freehead->prev = fmn;
+ freehead = fmn;
+}
+
+void CG_InitMemory( void )
+{
+ // Set up the initial node
+
+ freehead = (struct freememnode *) memoryPool;
+ freehead->cookie = FREEMEMCOOKIE;
+ freehead->size = POOLSIZE;
+ freehead->next = NULL;
+ freehead->prev = NULL;
+ freemem = sizeof(memoryPool);
+}
+
+void CG_DefragmentMemory( void )
+{
+ // If there's a frenzy of deallocation and we want to
+ // allocate something big, this is useful. Otherwise...
+ // not much use.
+
+ struct freememnode *startfmn, *endfmn, *fmn;
+
+ for( startfmn = freehead; startfmn; )
+ {
+ endfmn = (struct freememnode *)(((char *) startfmn) + startfmn->size);
+ for( fmn = freehead; fmn; )
+ {
+ if( fmn->cookie != FREEMEMCOOKIE )
+ CG_Error( "CG_DefragmentMemory: Memory corruption detected!\n" );
+
+ if( fmn == endfmn )
+ {
+ // We can add fmn onto startfmn.
+
+ if( fmn->prev )
+ fmn->prev->next = fmn->next;
+ if( fmn->next )
+ {
+ if( !(fmn->next->prev = fmn->prev) )
+ freehead = fmn->next; // We're removing the head node
+ }
+ startfmn->size += fmn->size;
+ memset( fmn, 0, sizeof(struct freememnode) ); // A redundant call, really.
+
+ startfmn = freehead;
+ endfmn = fmn = NULL; // Break out of current loop
+ }
+ else
+ fmn = fmn->next;
+ }
+
+ if( endfmn )
+ startfmn = startfmn->next; // endfmn acts as a 'restart' flag here
+ }
+}
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