FS#8961 - Anti-Aliased Fonts.
[kugel-rb.git] / apps / plugins / doom / z_bmalloc.c
blob47a9b4f892c8d661711b24f6edaa8f1399f34601
1 /* Emacs style mode select -*- C++ -*-
2 *-----------------------------------------------------------------------------
5 * PrBoom a Doom port merged with LxDoom and LSDLDoom
6 * based on BOOM, a modified and improved DOOM engine
7 * Copyright (C) 1999 by
8 * id Software, Chi Hoang, Lee Killough, Jim Flynn, Rand Phares, Ty Halderman
9 * Copyright (C) 1999-2000 by
10 * Jess Haas, Nicolas Kalkhof, Colin Phipps, Florian Schulze
12 * This program is free software; you can redistribute it and/or
13 * modify it under the terms of the GNU General Public License
14 * as published by the Free Software Foundation; either version 2
15 * of the License, or (at your option) any later version.
17 * This program is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 * GNU General Public License for more details.
22 * You should have received a copy of the GNU General Public License
23 * along with this program; if not, write to the Free Software
24 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
25 * 02111-1307, USA.
27 * DESCRIPTION:
28 * This is designed to be a fast allocator for small, regularly used block sizes
29 *-----------------------------------------------------------------------------
31 #include "doomtype.h"
32 #include "z_zone.h"
33 #include "z_bmalloc.h"
34 #include "i_system.h"
35 #include "rockmacros.h"
37 typedef struct bmalpool_s {
38 struct bmalpool_s *nextpool;
39 size_t blocks;
40 byte used[0];
41 } bmalpool_t;
43 inline static void* getelem(bmalpool_t *p, size_t size, size_t n)
45 return (((byte*)p) + sizeof(bmalpool_t) + sizeof(byte)*(p->blocks) + size*n);
48 inline static int iselem(const bmalpool_t *pool, size_t size, const void* p)
50 // CPhipps - need portable # of bytes between pointers
51 int dif = (const char*)p - (const char*)pool;
53 dif -= sizeof(bmalpool_t);
54 dif -= pool->blocks;
55 if (dif<0) return -1;
56 dif /= size;
57 return (((size_t)dif >= pool->blocks) ? -1 : dif);
60 enum { unused_block = 0, used_block = 1};
62 void* Z_BMalloc(struct block_memory_alloc_s *pzone)
64 register bmalpool_t **pool = (bmalpool_t **)&(pzone->firstpool);
65 while (*pool != NULL) {
66 byte *p = memchr((*pool)->used, unused_block, (*pool)->blocks); // Scan for unused marker
67 if (p) {
68 int n = p - (*pool)->used;
69 #ifdef SIMPLECHECKS
70 if ((n<0) || ((size_t)n>=(*pool)->blocks))
71 I_Error("Z_BMalloc: memchr returned pointer outside of array");
72 #endif
73 (*pool)->used[n] = used_block;
74 return getelem(*pool, pzone->size, n);
75 } else
76 pool = &((*pool)->nextpool);
79 // Nothing available, must allocate a new pool
80 bmalpool_t *newpool;
82 // CPhipps: Allocate new memory, initialised to 0
84 *pool = newpool = Z_Calloc(sizeof(*newpool) + (sizeof(byte) + pzone->size)*(pzone->perpool),
85 1, pzone->tag, NULL);
86 newpool->nextpool = NULL; // NULL = (void*)0 so this is redundant
88 // Return element 0 from this pool to satisfy the request
89 newpool->used[0] = used_block;
90 newpool->blocks = pzone->perpool;
91 return getelem(newpool, pzone->size, 0);
95 void Z_BFree(struct block_memory_alloc_s *pzone, void* p)
97 register bmalpool_t **pool = (bmalpool_t**)&(pzone->firstpool);
99 while (*pool != NULL) {
100 int n = iselem(*pool, pzone->size, p);
101 if (n >= 0) {
102 #ifdef SIMPLECHECKS
103 if ((*pool)->used[n] == unused_block)
104 I_Error("Z_BFree: Refree in zone %s", pzone->desc);
105 #endif
106 (*pool)->used[n] = unused_block;
107 if (memchr(((*pool)->used), used_block, (*pool)->blocks) == NULL) {
108 // Block is all unused, can be freed
109 bmalpool_t *oldpool = *pool;
110 *pool = (*pool)->nextpool;
111 Z_Free(oldpool);
113 return;
114 } else pool = &((*pool)->nextpool);
116 I_Error("Z_BFree: Free not in zone %s", pzone->desc);