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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␊
60size_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) (*zerror)((char *)0xdeadbeef, 0, file, line);␊
115 }␊
116#if BEST_FIT␊
117␉smallestSize = 0;␊
118␉bestFit = -1;␊
119#endif␊
120␊
121␉for (i = 0; i < availableNodes; i++)␊
122␉{␊
123␉␉// find node with equal size, or if not found,␊
124 // then smallest node that fits.␊
125␉␉if (zavailable[i].size == size)␊
126␉␉{␊
127␉␉␉zallocate(ret = zavailable[i].start, size);␊
128␉␉␉zdelete(zavailable, i); availableNodes--;␊
129␉␉␉goto done;␊
130␉␉}␊
131#if BEST_FIT␊
132␉␉else␊
133␉␉{␊
134␉␉␉if ((zavailable[i].size > size) && ((smallestSize == 0) || (zavailable[i].size < smallestSize)))␊
135␉␉␉{␊
136␉␉␉␉bestFit = i;␊
137␉␉␉␉smallestSize = zavailable[i].size;␊
138␉␉␉}␊
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␉{␊
154␉␉zallocate(ret = zavailable[bestFit].start, size);␊
155␉␉zavailable[bestFit].start += size;␊
156␉␉zavailable[bestFit].size -= size;␊
157␉}␊
158#endif␊
159␊
160done:␊
161␉if ((ret == 0) || (ret + size >= zalloc_end))␊
162␉{␊
163␉␉if (zerror) (*zerror)(ret, size, file, line);␊
164␉}␊
165␊
166␉if (ret != 0)␊
167␉{␊
168␉␉bzero(ret, size);␊
169␉}␊
170#if ZDEBUG␊
171␉zalloced_size += size;␊
172#endif␊
173␉return (void *) ret;␊
174}␊
175␊
176void free(void * pointer)␊
177{␊
178␉unsigned long rp;␊
179␉int i, found = 0;␊
180␉size_t tsize = 0;␊
181␉char * start = pointer;␊
182␊
183#if i386 ␊
184␉// Get return address of our caller,␊
185␉// in case we have to report an error below.␊
186␉asm volatile ("movl %%esp, %%eax\n\t"␊
187 "subl $4, %%eax\n\t"␊
188 "movl 0(%%eax), %%eax" : "=a" (rp));␊
189#else␊
190 rp = 0;␊
191#endif␊
192␊
193␉if (!start)␊
194␉return;␊
195␊
196␉for (i = 0; i < allocedNodes; i++)␊
197␉{␊
198␉␉if (zalloced[i].start == start)␊
199␉␉{␊
200␉␉␉tsize = zalloced[i].size;␊
201#if ZDEBUG␊
202␉␉␉zout -= tsize;␊
203␉␉␉printf(" zz out %d\n", zout);␊
204#endif␊
205␉␉␉zdelete(zalloced, i); allocedNodes--;␊
206␉␉␉found = 1;␊
207#if ZDEBUG␊
208␉␉␉memset(pointer, 0x5A, tsize);␊
209#endif␊
210␉␉␉break;␊
211␉␉}␊
212␉}␊
213␉if (!found)␊
214␉{␊
215␉␉if (zerror) (*zerror)(pointer, rp, "free", 0);␊
216␉␉else␊
217␉␉return;␊
218␉}␊
219#if ZDEBUG␊
220 zalloced_size -= tsize;␊
221#endif␊
222␊
223␉for (i = 0; i < availableNodes; i++)␊
224␉{␊
225␉␉if ((start + tsize) == zavailable[i].start) // merge it in␊
226␉␉{␊
227␉␉␉zavailable[i].start = start;␊
228␉␉␉zavailable[i].size += tsize;␊
229␉␉␉zcoalesce();␊
230␉␉␉return;␊
231␉␉}␊
232␊
233␉␉if ((i > 0) && (zavailable[i-1].start + zavailable[i-1].size == start))␊
234␉␉{␊
235␉␉␉zavailable[i-1].size += tsize;␊
236␉␉␉zcoalesce();␊
237␉␉␉return;␊
238␉␉}␊
239␊
240␉␉if ((start + tsize) < zavailable[i].start)␊
241␉␉{␊
242 if (++availableNodes > totalNodes)␊
243␉␉␉{␊
244␉␉␉␉if (zerror) (*zerror)((char *)0xf000f000, 0, "free", 0);␊
245␉␉␉}␊
246␉␉␉zinsert(zavailable, i); ␊
247␉␉␉zavailable[i].start = start;␊
248␉␉␉zavailable[i].size = tsize;␊
249␉␉␉return;␊
250␉␉}␊
251␉}␊
252␊
253␉if (++availableNodes > totalNodes)␊
254␉{␊
255␉␉if (zerror) (*zerror)((char *)0xf000f000, 1, "free", 0);␊
256␉}␊
257␉zavailable[i].start = start;␊
258␉zavailable[i].size = tsize;␊
259␉zcoalesce();␊
260␊
261␉return;␊
262}␊
263␊
264static void zallocate(char * start,int size)␊
265{␊
266␊
267#if ZDEBUG␊
268␉zout += size;␊
269␉printf(" alloc %d, total 0x%x\n",size,zout);␊
270#endif␊
271␊
272␉zalloced[allocedNodes].start = start;␊
273␉zalloced[allocedNodes].size = size;␊
274␊
275␉if (++allocedNodes > totalNodes)␊
276␉{␊
277␉␉if (zerror) (*zerror)((char *)0xf000f000, 2, "zallocate", 0);␊
278␉};␊
279}␊
280␊
281static void zinsert(zmem * zp, int ndx)␊
282{␊
283␉int i;␊
284␉zmem *z1, *z2;␊
285␊
286␉i = totalNodes-2;␊
287␉z1 = zp + i;␊
288␉z2 = z1 + 1;␊
289␊
290␉for (; i >= ndx; i--, z1--, z2--)␊
291␉{␊
292␉␉*z2 = *z1;␊
293␉}␊
294}␊
295␊
296static void zdelete(zmem * zp, int ndx)␊
297{␊
298␉int i;␊
299␉zmem *z1, *z2;␊
300␊
301␉z1 = zp + ndx;␊
302␉z2 = z1 + 1;␊
303␊
304␉for (i = ndx; i < totalNodes - 1; i++, z1++, z2++)␊
305␉{␊
306␉␉*z1 = *z2;␊
307␉}␊
308}␊
309␊
310static void zcoalesce(void)␊
311{␊
312␉int i;␊
313␊
314␉for (i = 0; i < availableNodes-1; i++)␊
315␉{␊
316␉␉if ( zavailable[i].start + zavailable[i].size == zavailable[i + 1].start )␊
317␉␉{␊
318␉␉␉zavailable[i].size += zavailable[i + 1].size;␊
319␉␉␉zdelete(zavailable, i + 1); availableNodes--;␊
320␉␉␉return;␊
321␉␉}␊
322␉}␉␊
323}␊
324␊
325/* This is the simplest way possible. Should fix this. */␊
326void * realloc(void * start, size_t newsize)␊
327{␊
328 void * newstart = safe_malloc(newsize, __FILE__, __LINE__);␊
329 bcopy(start, newstart, newsize);␊
330 free(start);␊
331 return newstart;␊
332}␊
333

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