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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 {␊
43␉char * start;␊
44␉size_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␊
60␉size_t zalloced_size;␊
61#endif␊
62␊
63#define ZALLOC_NODES␉32767 /* was 16384 */␊
64␊
65static void malloc_error(char *addr, size_t size, const char *file, int line)␊
66{␊
67#ifdef i386␊
68␉asm 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{␊
75␉zalloc_base = start ? start : (char *)ZALLOC_ADDR;␊
76␉totalNodes = nodes ? nodes : ZALLOC_NODES;␊
77␉zalloced = (zmem *) zalloc_base;␊
78␉zavailable = (zmem *) zalloc_base + sizeof(zmem) * totalNodes;␊
79␉zavailable[0].start = (char *)zavailable + sizeof(zmem) * totalNodes;␊
80␊
81␉if (size == 0)␊
82␉{␊
83␉␉size = ZALLOC_LEN;␊
84␉}␊
85␊
86␉zavailable[0].size = size - (zavailable[0].start - zalloc_base);␊
87␉zalloc_end = zalloc_base + size;␊
88␉availableNodes = 1;␊
89␉allocedNodes = 0;␊
90␉zerror = 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{␊
97␉int i;␊
98#if BEST_FIT␊
99␉int bestFit;␊
100␉size_t smallestSize;␊
101#endif␊
102␉char * ret = 0;␊
103␊
104␉if ( !zalloc_base )␊
105␉{␊
106␉␉// this used to follow the bss but some bios' corrupted it...␊
107␉␉malloc_init((char *)ZALLOC_ADDR, ZALLOC_LEN, ZALLOC_NODES, malloc_error);␊
108␉}␊
109␊
110␉size = ((size + 0xf) & ~0xf);␊
111␊
112␉if (size == 0)␊
113␉{␊
114␉␉if (zerror)␊
115␉␉{␊
116␉␉␉(*zerror)((char *)0xdeadbeef, 0, file, line);␊
117 ␉}␊
118 }␊
119#if BEST_FIT␊
120␉smallestSize = 0;␊
121␉bestFit = -1;␊
122#endif␊
123␊
124␉for (i = 0; i < availableNodes; i++)␊
125␉{␊
126␉␉// find node with equal size, or if not found,␊
127 // then smallest node that fits.␊
128␉␉if (zavailable[i].size == size)␊
129␉␉{␊
130␉␉␉zallocate(ret = zavailable[i].start, size);␊
131␉␉␉zdelete(zavailable, i); availableNodes--;␊
132␉␉␉goto done;␊
133␉␉}␊
134#if BEST_FIT␊
135␉␉else {␊
136␉␉␉if ((zavailable[i].size > size) && ((smallestSize == 0) || (zavailable[i].size < smallestSize))) {␊
137␉␉␉␉bestFit = i;␊
138␉␉␉␉smallestSize = zavailable[i].size;␊
139␉␉␉}␊
140␉␉}␊
141#else␊
142␉␉else if (zavailable[i].size > size)␊
143␉␉{␊
144␉␉␉zallocate(ret = zavailable[i].start, size);␊
145␉␉␉zavailable[i].start += size;␊
146␉␉␉zavailable[i].size -= size;␊
147␉␉␉goto done;␊
148␉␉}␊
149#endif␊
150␉}␊
151#if BEST_FIT␊
152␉if (bestFit != -1) {␊
153␉␉zallocate(ret = zavailable[bestFit].start, size);␊
154␉␉zavailable[bestFit].start += size;␊
155␉␉zavailable[bestFit].size -= size;␊
156␉}␊
157#endif␊
158␊
159done:␊
160␉if ((ret == 0) || (ret + size >= zalloc_end)) {␊
161␉␉if (zerror)␊
162␉␉{␊
163␉␉␉(*zerror)(ret, size, file, line);␊
164␉␉}␊
165␉}␊
166␊
167␉if (ret != 0)␊
168␉{␊
169␉␉bzero(ret, size);␊
170␉}␊
171#if ZDEBUG␊
172␉zalloced_size += size;␊
173#endif␊
174␉return (void *) ret;␊
175}␊
176␊
177void free(void * pointer)␊
178{␊
179␉unsigned long rp;␊
180␉int i, found = 0;␊
181␉size_t tsize = 0;␊
182␉char * start = pointer;␊
183␊
184#if i386 ␊
185␉// Get return address of our caller,␊
186␉// in case we have to report an error below.␊
187␉asm volatile ("movl %%esp, %%eax\n\t"␊
188 "subl $4, %%eax\n\t"␊
189 "movl 0(%%eax), %%eax" : "=a" (rp));␊
190#else␊
191 rp = 0;␊
192#endif␊
193␊
194␉if (!start)␊
195␉{␊
196␉␉return;␊
197␉}␊
198␊
199␉for (i = 0; i < allocedNodes; i++)␊
200␉{␊
201␉␉if (zalloced[i].start == start)␊
202␉␉{␊
203␉␉␉tsize = zalloced[i].size;␊
204#if ZDEBUG␊
205␉␉␉zout -= tsize;␊
206␉␉␉printf(" zz out %d\n", zout);␊
207#endif␊
208␉␉␉zdelete(zalloced, i); allocedNodes--;␊
209␉␉␉found = 1;␊
210#if ZDEBUG␊
211␉␉␉memset(pointer, 0x5A, tsize);␊
212#endif␊
213␉␉␉break;␊
214␉␉}␊
215␉}␊
216␉if (!found)␊
217␉{␊
218␉␉if (zerror)␊
219␉␉{␊
220␉␉␉(*zerror)(pointer, rp, "free", 0);␊
221␉␉} else {␊
222␉␉␉return;␊
223␉␉}␊
224␉}␊
225#if ZDEBUG␊
226 zalloced_size -= tsize;␊
227#endif␊
228␊
229␉for (i = 0; i < availableNodes; i++)␊
230␉{␊
231␉␉if ((start + tsize) == zavailable[i].start) // merge it in␊
232␉␉{␊
233␉␉␉zavailable[i].start = start;␊
234␉␉␉zavailable[i].size += tsize;␊
235␉␉␉zcoalesce();␊
236␉␉␉return;␊
237␉␉}␊
238␊
239␉␉if ((i > 0) && (zavailable[i-1].start + zavailable[i-1].size == start))␊
240␉␉{␊
241␉␉␉zavailable[i-1].size += tsize;␊
242␉␉␉zcoalesce();␊
243␉␉␉return;␊
244␉␉}␊
245␊
246␉␉if ((start + tsize) < zavailable[i].start)␊
247␉␉{␊
248 if (++availableNodes > totalNodes)␊
249␉␉␉{␊
250␉␉␉␉if (zerror)␊
251␉␉␉␉{␊
252␉␉␉␉␉(*zerror)((char *)0xf000f000, 0, "free", 0);␊
253␉␉␉␉}␊
254␉␉␉}␊
255␉␉␉zinsert(zavailable, i); ␊
256␉␉␉zavailable[i].start = start;␊
257␉␉␉zavailable[i].size = tsize;␊
258␉␉␉return;␊
259␉␉}␊
260␉}␊
261␊
262␉if (++availableNodes > totalNodes)␊
263␉{␊
264␉␉if (zerror)␊
265␉␉{␊
266␉␉␉(*zerror)((char *)0xf000f000, 1, "free", 0);␊
267␉␉}␊
268␉}␊
269␉zavailable[i].start = start;␊
270␉zavailable[i].size = tsize;␊
271␉zcoalesce();␊
272␊
273␉return;␊
274}␊
275␊
276static void␊
277zallocate(char * start,int size)␊
278{␊
279␊
280#if ZDEBUG␊
281␉zout += size;␊
282␉printf(" alloc %d, total 0x%x\n",size,zout);␊
283#endif␊
284␊
285␉zalloced[allocedNodes].start = start;␊
286␉zalloced[allocedNodes].size = size;␊
287␊
288␉if (++allocedNodes > totalNodes)␊
289␉{␊
290␉␉if (zerror)␊
291␉␉{␊
292␉␉␉(*zerror)((char *)0xf000f000, 2, "zallocate", 0);␊
293␉␉}␊
294␉};␊
295}␊
296␊
297static void␊
298zinsert(zmem * zp, int ndx)␊
299{␊
300␉int i;␊
301␉zmem *z1, *z2;␊
302␊
303␉i = totalNodes-2;␊
304␉z1 = zp + i;␊
305␉z2 = z1 + 1;␊
306␊
307␉for (; i >= ndx; i--, z1--, z2--)␊
308␉{␊
309␉␉*z2 = *z1;␊
310␉}␊
311}␊
312␊
313static void␊
314zdelete(zmem * zp, int ndx)␊
315{␊
316␉int i;␊
317␉zmem *z1, *z2;␊
318␊
319␉z1 = zp + ndx;␊
320␉z2 = z1 + 1;␊
321␊
322␉for (i = ndx; i < totalNodes - 1; i++, z1++, z2++)␊
323␉{␊
324␉␉*z1 = *z2;␊
325␉}␊
326}␊
327␊
328static void␊
329zcoalesce(void)␊
330{␊
331␉int i;␊
332␊
333␉for (i = 0; i < availableNodes-1; i++)␊
334␉{␊
335␉␉if ( zavailable[i].start + zavailable[i].size == zavailable[i + 1].start )␊
336␉␉{␊
337␉␉␉zavailable[i].size += zavailable[i + 1].size;␊
338␉␉␉zdelete(zavailable, i + 1); availableNodes--;␊
339␉␉␉return;␊
340␉␉}␊
341␉}␉␊
342}␊
343␊
344/* This is the simplest way possible. Should fix this. */␊
345void * realloc(void * start, size_t newsize)␊
346{␊
347 void * newstart = safe_malloc(newsize, __FILE__, __LINE__);␊
348 bcopy(start, newstart, newsize);␊
349 free(start);␊
350 return newstart;␊
351}␊
352

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