1 /*
2  * This module derived from code donated to the FreeBSD Project by
3  * Matthew Dillon <dillon@backplane.com>
4  *
5  * Copyright (c) 1998 The FreeBSD Project
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #include <sys/cdefs.h>
31 
32 /*
33  * MALLOC.C - malloc equivalent, runs on top of zalloc and uses sbrk
34  */
35 
36 #include "zalloc_defs.h"
37 
38 static MemPool	MallocPool;
39 
40 #ifdef DMALLOCDEBUG
41 static int MallocMax;
42 static int MallocCount;
43 
44 void mallocstats(void);
45 #endif
46 
47 #ifdef malloc
48 #undef malloc
49 #undef free
50 #endif
51 
52 static void *Malloc_align(size_t, size_t);
53 
54 void *
Malloc(size_t bytes,const char * file __unused,int line __unused)55 Malloc(size_t bytes, const char *file __unused, int line __unused)
56 {
57 	return (Malloc_align(bytes, 1));
58 }
59 
60 void *
Memalign(size_t alignment,size_t bytes,const char * file __unused,int line __unused)61 Memalign(size_t alignment, size_t bytes, const char *file __unused,
62     int line __unused)
63 {
64 	if (alignment == 0)
65 		alignment = 1;
66 
67 	return (Malloc_align(bytes, alignment));
68 }
69 
70 static void *
Malloc_align(size_t bytes,size_t alignment)71 Malloc_align(size_t bytes, size_t alignment)
72 {
73 	Guard *res;
74 
75 #ifdef USEENDGUARD
76 	bytes += MALLOCALIGN + 1;
77 #else
78 	bytes += MALLOCALIGN;
79 #endif
80 
81 	while ((res = znalloc(&MallocPool, bytes, alignment)) == NULL) {
82 		int incr = (bytes + BLKEXTENDMASK) & ~BLKEXTENDMASK;
83 		char *base;
84 
85 		if ((base = sbrk(incr)) == (char *)-1)
86 			return (NULL);
87 		zextendPool(&MallocPool, base, incr);
88 		zfree(&MallocPool, base, incr);
89 	}
90 #ifdef DMALLOCDEBUG
91 	if (++MallocCount > MallocMax)
92 		MallocMax = MallocCount;
93 #endif
94 #ifdef USEGUARD
95 	res->ga_Magic = GAMAGIC;
96 #endif
97 	res->ga_Bytes = bytes;
98 #ifdef USEENDGUARD
99 	*((signed char *)res + bytes - 1) = -2;
100 #endif
101 
102 	return ((char *)res + MALLOCALIGN);
103 }
104 
105 void
Free(void * ptr,const char * file,int line)106 Free(void *ptr, const char *file, int line)
107 {
108 	size_t bytes;
109 
110 	if (ptr != NULL) {
111 		Guard *res = (void *)((char *)ptr - MALLOCALIGN);
112 
113 		if (file == NULL)
114 			file = "unknown";
115 #ifdef USEGUARD
116 		if (res->ga_Magic == GAFREE) {
117 			printf("free: duplicate free @ %p from %s:%d\n",
118 			    ptr, file, line);
119 			return;
120 		}
121 		if (res->ga_Magic != GAMAGIC)
122 			panic("free: guard1 fail @ %p from %s:%d",
123 			    ptr, file, line);
124 		res->ga_Magic = GAFREE;
125 #endif
126 #ifdef USEENDGUARD
127 		if (*((signed char *)res + res->ga_Bytes - 1) == -1) {
128 			printf("free: duplicate2 free @ %p from %s:%d\n",
129 			    ptr, file, line);
130 			return;
131 		}
132 		if (*((signed char *)res + res->ga_Bytes - 1) != -2)
133 			panic("free: guard2 fail @ %p + %zu from %s:%d",
134 			    ptr, res->ga_Bytes - MALLOCALIGN, file, line);
135 		*((signed char *)res + res->ga_Bytes - 1) = -1;
136 #endif
137 
138 		bytes = res->ga_Bytes;
139 		zfree(&MallocPool, res, bytes);
140 #ifdef DMALLOCDEBUG
141 		--MallocCount;
142 #endif
143 	}
144 }
145 
146 void *
Calloc(size_t n1,size_t n2,const char * file,int line)147 Calloc(size_t n1, size_t n2, const char *file, int line)
148 {
149 	uintptr_t bytes = (uintptr_t)n1 * (uintptr_t)n2;
150 	void *res;
151 
152 	if ((res = Malloc(bytes, file, line)) != NULL) {
153 		bzero(res, bytes);
154 #ifdef DMALLOCDEBUG
155 		if (++MallocCount > MallocMax)
156 			MallocMax = MallocCount;
157 #endif
158 	}
159 	return (res);
160 }
161 
162 /*
163  * realloc() - I could be fancier here and free the old buffer before
164  *	       allocating the new one (saving potential fragmentation
165  *	       and potential buffer copies).  But I don't bother.
166  */
167 
168 void *
Realloc(void * ptr,size_t size,const char * file,int line)169 Realloc(void *ptr, size_t size, const char *file, int line)
170 {
171 	void *res;
172 	size_t old;
173 
174 	if ((res = Malloc(size, file, line)) != NULL) {
175 		if (ptr != NULL) {
176 			Guard *g = (Guard *)((char *)ptr - MALLOCALIGN);
177 
178 			old = g->ga_Bytes - MALLOCALIGN;
179 			if (old < size)
180 				bcopy(ptr, res, old);
181 			else
182 				bcopy(ptr, res, size);
183 			Free(ptr, file, line);
184 		} else {
185 #ifdef DMALLOCDEBUG
186 			if (++MallocCount > MallocMax)
187 				MallocMax = MallocCount;
188 #ifdef EXITSTATS
189 			if (DidAtExit == 0) {
190 				DidAtExit = 1;
191 				atexit(mallocstats);
192 			}
193 #endif
194 #endif
195 		}
196 	}
197 	return (res);
198 }
199 
200 void *
Reallocf(void * ptr,size_t size,const char * file,int line)201 Reallocf(void *ptr, size_t size, const char *file, int line)
202 {
203 	void *res;
204 
205 	if ((res = Realloc(ptr, size, file, line)) == NULL)
206 		Free(ptr, file, line);
207 	return (res);
208 }
209 
210 #ifdef DMALLOCDEBUG
211 
212 void
mallocstats(void)213 mallocstats(void)
214 {
215 	printf("Active Allocations: %d/%d\n", MallocCount, MallocMax);
216 #ifdef ZALLOCDEBUG
217 	zallocstats(&MallocPool);
218 #endif
219 }
220 
221 #endif
222