VirtualBox

source: vbox/trunk/src/VBox/Runtime/r3/win32/alloc-win32.cpp@ 5285

Last change on this file since 5285 was 4071, checked in by vboxsync, 17 years ago

Biggest check-in ever. New source code headers for all (C) innotek files.

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File size: 6.3 KB
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1/* $Id: alloc-win32.cpp 4071 2007-08-07 17:07:59Z vboxsync $ */
2/** @file
3 * innotek Portable Runtime - Memory Allocation, Win32.
4 */
5
6/*
7 * Copyright (C) 2006-2007 innotek GmbH
8 *
9 * This file is part of VirtualBox Open Source Edition (OSE), as
10 * available from http://www.virtualbox.org. This file is free software;
11 * you can redistribute it and/or modify it under the terms of the GNU
12 * General Public License as published by the Free Software Foundation,
13 * in version 2 as it comes in the "COPYING" file of the VirtualBox OSE
14 * distribution. VirtualBox OSE is distributed in the hope that it will
15 * be useful, but WITHOUT ANY WARRANTY of any kind.
16 */
17
18
19/*******************************************************************************
20* Header Files *
21*******************************************************************************/
22#define LOG_GROUP RTLOGGROUP_MEM
23#include <Windows.h>
24
25#include <iprt/alloc.h>
26#include <iprt/assert.h>
27#include <iprt/param.h>
28#include <iprt/string.h>
29#include <iprt/err.h>
30
31#ifndef USE_VIRTUAL_ALLOC
32# include <malloc.h>
33#endif
34
35
36/**
37 * Allocates memory which may contain code.
38 *
39 * @returns Pointer to the allocated memory.
40 * @returns NULL on failure.
41 * @param cb Size in bytes of the memory block to allocate.
42 */
43RTDECL(void *) RTMemExecAlloc(size_t cb)
44{
45 /*
46 * Allocate first.
47 */
48 AssertMsg(cb, ("Allocating ZERO bytes is really not a good idea! Good luck with the next assertion!\n"));
49 cb = RT_ALIGN_Z(cb, 32);
50 void *pv = malloc(cb);
51 AssertMsg(pv, ("malloc(%d) failed!!!\n", cb));
52 if (pv)
53 {
54 /*
55 * Add PROT_EXEC flag to the page.
56 *
57 * This is in violation of the SuS where I think it saith that mprotect() shall
58 * only be used with mmap()'ed memory. Works on linux and OS/2 LIBC v0.6.
59 */
60 memset(pv, 0xcc, cb);
61 void *pvProt = (void *)((uintptr_t)pv & ~PAGE_OFFSET_MASK);
62 size_t cbProt = ((uintptr_t)pv & PAGE_OFFSET_MASK) + cb;
63 cbProt = RT_ALIGN_Z(cbProt, PAGE_SIZE);
64 DWORD fFlags = 0;
65 if (!VirtualProtect(pvProt, cbProt, PAGE_EXECUTE_READWRITE, &fFlags))
66 {
67 AssertMsgFailed(("VirtualProtect(%p, %#x,,) -> lasterr=%d\n", pvProt, cbProt, GetLastError()));
68 free(pv);
69 pv = NULL;
70 }
71 }
72 return pv;
73}
74
75
76/**
77 * Free executable/read/write memory allocated by RTMemExecAlloc().
78 *
79 * @param pv Pointer to memory block.
80 */
81RTDECL(void) RTMemExecFree(void *pv)
82{
83 if (pv)
84 free(pv);
85}
86
87
88/**
89 * Allocate page aligned memory.
90 *
91 * @returns Pointer to the allocated memory.
92 * @returns NULL if we're out of memory.
93 * @param cb Size of the memory block. Will be rounded up to page size.
94 */
95RTDECL(void *) RTMemPageAlloc(size_t cb)
96{
97#ifdef USE_VIRTUAL_ALLOC
98 void *pv = VirtualAlloc(NULL, RT_ALIGN_Z(cb, PAGE_SIZE), MEM_COMMIT, PAGE_READWRITE);
99#else
100 void *pv = _aligned_malloc(cb, PAGE_SIZE);
101#endif
102 AssertMsg(pv, ("cb=%d lasterr=%d\n", cb, GetLastError()));
103 return pv;
104}
105
106
107/**
108 * Allocate zero'ed page aligned memory.
109 *
110 * @returns Pointer to the allocated memory.
111 * @returns NULL if we're out of memory.
112 * @param cb Size of the memory block. Will be rounded up to page size.
113 */
114RTDECL(void *) RTMemPageAllocZ(size_t cb)
115{
116#ifdef USE_VIRTUAL_ALLOC
117 void *pv = VirtualAlloc(NULL, RT_ALIGN_Z(cb, PAGE_SIZE), MEM_COMMIT, PAGE_READWRITE);
118#else
119 void *pv = _aligned_malloc(cb, PAGE_SIZE);
120#endif
121 if (pv)
122 {
123 memset(pv, 0, RT_ALIGN_Z(cb, PAGE_SIZE));
124 return pv;
125 }
126 AssertMsgFailed(("cb=%d lasterr=%d\n", cb, GetLastError()));
127 return NULL;
128}
129
130
131/**
132 * Free a memory block allocated with RTMemPageAlloc() or RTMemPageAllocZ().
133 *
134 * @param pv Pointer to the block as it was returned by the allocation function.
135 * NULL will be ignored.
136 */
137RTDECL(void) RTMemPageFree(void *pv)
138{
139 if (pv)
140 {
141#ifdef USE_VIRTUAL_ALLOC
142 if (!VirtualFree(pv, 0, MEM_RELEASE))
143 AssertMsgFailed(("pv=%p lasterr=%d\n", pv, GetLastError()));
144#else
145 _aligned_free(pv);
146#endif
147 }
148}
149
150
151/**
152 * Change the page level protection of a memory region.
153 *
154 * @returns iprt status code.
155 * @param pv Start of the region. Will be rounded down to nearest page boundary.
156 * @param cb Size of the region. Will be rounded up to the nearest page boundary.
157 * @param fProtect The new protection, a combination of the RTMEM_PROT_* defines.
158 */
159RTDECL(int) RTMemProtect(void *pv, size_t cb, unsigned fProtect)
160{
161 /*
162 * Validate input.
163 */
164 if (cb == 0)
165 {
166 AssertMsgFailed(("!cb\n"));
167 return VERR_INVALID_PARAMETER;
168 }
169 if (fProtect & ~(RTMEM_PROT_NONE | RTMEM_PROT_READ | RTMEM_PROT_WRITE | RTMEM_PROT_EXEC))
170 {
171 AssertMsgFailed(("fProtect=%#x\n", fProtect));
172 return VERR_INVALID_PARAMETER;
173 }
174
175 /*
176 * Convert the flags.
177 */
178 int fProt;
179 Assert(!RTMEM_PROT_NONE);
180 switch (fProtect & (RTMEM_PROT_NONE | RTMEM_PROT_READ | RTMEM_PROT_WRITE | RTMEM_PROT_EXEC))
181 {
182 case RTMEM_PROT_NONE:
183 fProt = PAGE_NOACCESS;
184 break;
185
186 case RTMEM_PROT_READ:
187 fProt = PAGE_READONLY;
188 break;
189
190 case RTMEM_PROT_READ | RTMEM_PROT_WRITE:
191 fProt = PAGE_READWRITE;
192 break;
193
194 case RTMEM_PROT_READ | RTMEM_PROT_WRITE | RTMEM_PROT_EXEC:
195 fProt = PAGE_EXECUTE_READWRITE;
196 break;
197
198 case RTMEM_PROT_READ | RTMEM_PROT_EXEC:
199 fProt = PAGE_EXECUTE_READWRITE;
200 break;
201
202 case RTMEM_PROT_WRITE:
203 fProt = PAGE_READWRITE;
204 break;
205
206 case RTMEM_PROT_WRITE | RTMEM_PROT_EXEC:
207 fProt = PAGE_EXECUTE_READWRITE;
208 break;
209
210 case RTMEM_PROT_EXEC:
211 fProt = PAGE_EXECUTE_READWRITE;
212 break;
213
214 /* If the compiler had any brains it would warn about this case. */
215 default:
216 AssertMsgFailed(("fProtect=%#x\n", fProtect));
217 return VERR_INTERNAL_ERROR;
218 }
219
220 /*
221 * Align the request.
222 */
223 cb += (uintptr_t)pv & PAGE_OFFSET_MASK;
224 pv = (void *)((uintptr_t)pv & ~PAGE_OFFSET_MASK);
225
226 /*
227 * Change the page attributes.
228 */
229 DWORD fFlags = 0;
230 if (VirtualProtect(pv, cb, fProt, &fFlags))
231 return VINF_SUCCESS;
232 return RTErrConvertFromWin32(GetLastError());
233}
234
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