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1/*
2 * Copyright (c) 1999-2003 Apple Computer, Inc. All rights reserved.
3 *
4 * @APPLE_LICENSE_HEADER_START@
5 *
6 * Portions Copyright (c) 1999-2003 Apple Computer, Inc. All Rights
7 * Reserved. This file contains Original Code and/or Modifications of
8 * Original Code as defined in and that are subject to the Apple Public
9 * Source License Version 2.0 (the "License"). You may not use this file
10 * except in compliance with the License. Please obtain a copy of the
11 * License at http://www.apple.com/publicsource and read it before using
12 * this file.
13 *
14 * The Original Code and all software distributed under the License are
15 * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
16 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
17 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE OR NON- INFRINGEMENT. Please see the
19 * License for the specific language governing rights and limitations
20 * under the License.
21 *
22 * @APPLE_LICENSE_HEADER_END@
23 */
24/*
25 * Copyright 1993 NeXT Computer, Inc.
26 * All rights reserved.
27 *
28 * Sam's simple memory allocator.
29 *
30 */
31
32#include "libsa.h"
33//#include "saio_internal.h" - Azi: needed for ZDEBUG (printf)
34#include "memory.h"
35
36#define ZDEBUG 0 //Azi: booter doesn't load with this enabled; instant reboot at "boot1: ..."
37
38#if ZDEBUG
39int zout;
40#endif
41
42typedef struct {
43char * start;
44size_t size;
45} zmem;
46
47static zmem * zalloced;
48static zmem * zavailable;
49static short availableNodes, allocedNodes, totalNodes;
50static char * zalloc_base;
51static char * zalloc_end;
52static void (*zerror)(char *, size_t, const char *, int);
53
54static void zallocate(char * start,int size);
55static void zinsert(zmem * zp, int ndx);
56static void zdelete(zmem * zp, int ndx);
57static void zcoalesce(void);
58
59#if ZDEBUG
60size_t zalloced_size;
61#endif
62
63#define ZALLOC_NODES32767 /* was 16384 */
64
65static void malloc_error(char *addr, size_t size, const char *file, int line)
66{
67#ifdef i386
68asm volatile ("hlt");
69#endif
70}
71
72// define the block of memory that the allocator will use
73void malloc_init(char * start, int size, int nodes, void (*malloc_err_fn)(char *, size_t, const char *, int))
74{
75zalloc_base = start ? start : (char *)ZALLOC_ADDR;
76totalNodes = nodes ? nodes : ZALLOC_NODES;
77zalloced = (zmem *) zalloc_base;
78zavailable = (zmem *) zalloc_base + sizeof(zmem) * totalNodes;
79zavailable[0].start = (char *)zavailable + sizeof(zmem) * totalNodes;
80
81if (size == 0)
82{
83size = ZALLOC_LEN;
84}
85
86zavailable[0].size = size - (zavailable[0].start - zalloc_base);
87zalloc_end = zalloc_base + size;
88availableNodes = 1;
89allocedNodes = 0;
90zerror = malloc_err_fn ? malloc_err_fn : malloc_error;
91}
92
93#define BEST_FIT 1
94
95void * safe_malloc(size_t size, const char *file, int line)
96{
97int i;
98#if BEST_FIT
99int bestFit;
100size_t smallestSize;
101#endif
102char * ret = 0;
103
104if ( !zalloc_base )
105{
106// this used to follow the bss but some bios' corrupted it...
107malloc_init((char *)ZALLOC_ADDR, ZALLOC_LEN, ZALLOC_NODES, malloc_error);
108}
109
110size = ((size + 0xf) & ~0xf);
111
112if (size == 0)
113{
114if (zerror)
115{
116(*zerror)((char *)0xdeadbeef, 0, file, line);
117 }
118 }
119#if BEST_FIT
120smallestSize = 0;
121bestFit = -1;
122#endif
123
124for (i = 0; i < availableNodes; i++)
125{
126// find node with equal size, or if not found,
127 // then smallest node that fits.
128if (zavailable[i].size == size)
129{
130zallocate(ret = zavailable[i].start, size);
131zdelete(zavailable, i); availableNodes--;
132goto done;
133}
134#if BEST_FIT
135else {
136if ((zavailable[i].size > size) && ((smallestSize == 0) || (zavailable[i].size < smallestSize))) {
137bestFit = i;
138smallestSize = zavailable[i].size;
139}
140}
141#else
142else if (zavailable[i].size > size)
143{
144zallocate(ret = zavailable[i].start, size);
145zavailable[i].start += size;
146zavailable[i].size -= size;
147goto done;
148}
149#endif
150}
151#if BEST_FIT
152if (bestFit != -1) {
153zallocate(ret = zavailable[bestFit].start, size);
154zavailable[bestFit].start += size;
155zavailable[bestFit].size -= size;
156}
157#endif
158
159done:
160if ((ret == 0) || (ret + size >= zalloc_end))
161{
162if (zerror)
163{
164(*zerror)(ret, size, file, line);
165}
166}
167
168if (ret != 0)
169{
170bzero(ret, size);
171}
172#if ZDEBUG
173zalloced_size += size;
174#endif
175return (void *) ret;
176}
177
178void free(void * pointer)
179{
180unsigned long rp;
181int i, found = 0;
182size_t tsize = 0;
183char * start = pointer;
184
185#if i386
186// Get return address of our caller,
187// in case we have to report an error below.
188asm volatile ("movl %%esp, %%eax\n\t"
189 "subl $4, %%eax\n\t"
190 "movl 0(%%eax), %%eax" : "=a" (rp));
191#else
192 rp = 0;
193#endif
194
195if (!start)
196{
197return;
198}
199
200for (i = 0; i < allocedNodes; i++)
201{
202if (zalloced[i].start == start)
203{
204tsize = zalloced[i].size;
205#if ZDEBUG
206zout -= tsize;
207printf(" zz out %d\n", zout);
208#endif
209zdelete(zalloced, i); allocedNodes--;
210found = 1;
211#if ZDEBUG
212memset(pointer, 0x5A, tsize);
213#endif
214break;
215}
216}
217if (!found)
218{
219if (zerror)
220{
221(*zerror)(pointer, rp, "free", 0);
222} else {
223return;
224}
225}
226#if ZDEBUG
227 zalloced_size -= tsize;
228#endif
229
230for (i = 0; i < availableNodes; i++)
231{
232if ((start + tsize) == zavailable[i].start) // merge it in
233{
234zavailable[i].start = start;
235zavailable[i].size += tsize;
236zcoalesce();
237return;
238}
239
240if ((i > 0) && (zavailable[i-1].start + zavailable[i-1].size == start))
241{
242zavailable[i-1].size += tsize;
243zcoalesce();
244return;
245}
246
247if ((start + tsize) < zavailable[i].start)
248{
249 if (++availableNodes > totalNodes)
250{
251if (zerror)
252{
253(*zerror)((char *)0xf000f000, 0, "free", 0);
254}
255}
256zinsert(zavailable, i);
257zavailable[i].start = start;
258zavailable[i].size = tsize;
259return;
260}
261}
262
263if (++availableNodes > totalNodes)
264{
265if (zerror)
266{
267(*zerror)((char *)0xf000f000, 1, "free", 0);
268}
269}
270zavailable[i].start = start;
271zavailable[i].size = tsize;
272zcoalesce();
273
274return;
275}
276
277static void
278zallocate(char * start,int size)
279{
280
281#if ZDEBUG
282zout += size;
283printf(" alloc %d, total 0x%x\n",size,zout);
284#endif
285
286zalloced[allocedNodes].start = start;
287zalloced[allocedNodes].size = size;
288
289if (++allocedNodes > totalNodes)
290{
291if (zerror)
292{
293(*zerror)((char *)0xf000f000, 2, "zallocate", 0);
294}
295};
296}
297
298static void
299zinsert(zmem * zp, int ndx)
300{
301int i;
302zmem *z1, *z2;
303
304i = totalNodes-2;
305z1 = zp + i;
306z2 = z1 + 1;
307
308for (; i >= ndx; i--, z1--, z2--)
309{
310*z2 = *z1;
311}
312}
313
314static void
315zdelete(zmem * zp, int ndx)
316{
317int i;
318zmem *z1, *z2;
319
320z1 = zp + ndx;
321z2 = z1 + 1;
322
323for (i = ndx; i < totalNodes - 1; i++, z1++, z2++)
324{
325*z1 = *z2;
326}
327}
328
329static void
330zcoalesce(void)
331{
332int i;
333
334for (i = 0; i < availableNodes-1; i++)
335{
336if ( zavailable[i].start + zavailable[i].size == zavailable[i + 1].start )
337{
338zavailable[i].size += zavailable[i + 1].size;
339zdelete(zavailable, i + 1); availableNodes--;
340return;
341}
342}
343}
344
345/* This is the simplest way possible. Should fix this. */
346void * realloc(void * start, size_t newsize)
347{
348 void * newstart = safe_malloc(newsize, __FILE__, __LINE__);
349 bcopy(start, newstart, newsize);
350 free(start);
351 return newstart;
352}
353

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