4 * Copyright (C) 2013 JP Ikaheimonen <jp_ikaheimonen@mentor.com>
5 * 2016 Michael Jeanson <mjeanson@efficios.com>
7 * These sources are based on ftp://g.oswego.edu/pub/misc/malloc.c
8 * file by Doug Lea, released to the public domain.
10 * Permission is hereby granted, free of charge, to any person obtaining a copy
11 * of this software and associated documentation files (the "Software"), to deal
12 * in the Software without restriction, including without limitation the rights
13 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
14 * copies of the Software, and to permit persons to whom the Software is
15 * furnished to do so, subject to the following conditions:
17 * The above copyright notice and this permission notice shall be included in
18 * all copies or substantial portions of the Software.
20 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
21 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
23 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
24 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
25 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
29 #define BT_LOG_OUTPUT_LEVEL (mapping->log_level)
30 #define BT_LOG_TAG "COMPAT/MMAN"
31 #include "logging/log.h"
33 #include "common/macros.h"
37 * On macOS, we need a dummy symbol so that the linker won't
38 * complain of an empty table of contents.
41 int bt_mman_dummy_symbol
;
42 #endif /* __APPLE__ */
53 #include "compat/mman.h"
58 /* The duplicated handle. */
60 /* Handle returned by CreateFileMapping. */
65 GHashTable
*mmap_mappings
= NULL
;
68 * This mutex protects the hashtable of memory mappings.
70 static pthread_mutex_t mmap_mutex
= PTHREAD_MUTEX_INITIALIZER
;
73 struct mmap_mapping
*mapping_create(void)
75 struct mmap_mapping
*mapping
;
77 mapping
= malloc(sizeof(struct mmap_mapping
));
78 if (mapping
!= NULL
) {
79 mapping
->file_handle
= NULL
;
80 mapping
->map_handle
= NULL
;
87 void mapping_clean(struct mmap_mapping
*mapping
)
90 if (!CloseHandle(mapping
->map_handle
)) {
91 BT_LOGF_STR("Failed to close mmap map_handle.");
94 if (!CloseHandle(mapping
->file_handle
)) {
95 BT_LOGF_STR("Failed to close mmap file_handle.");
104 void addr_clean(void *addr
)
106 /* Cleanup of handles should never fail. */
107 if (!UnmapViewOfFile(addr
)) {
109 * FIXME: We don't have access to the mapping's log
110 * level here, so force a FATAL level.
112 BT_LOG_WRITE_CUR_LVL(BT_LOG_FATAL
, BT_LOG_FATAL
, BT_LOG_TAG
,
113 "Failed to unmap mmap mapping.");
119 void mmap_lock(int log_level
)
121 if (pthread_mutex_lock(&mmap_mutex
)) {
122 BT_LOGF_STR("Failed to acquire mmap_mutex.");
128 void mmap_unlock(int log_level
)
130 if (pthread_mutex_unlock(&mmap_mutex
)) {
131 BT_LOGF_STR("Failed to release mmap_mutex.");
137 * Convert mmap memory protection flags to CreateFileMapping page protection
138 * flag and MapViewOfFile desired access flag.
141 DWORD
map_prot_flags(int prot
, DWORD
*dwDesiredAccess
)
143 if (prot
& PROT_READ
) {
144 if (prot
& PROT_WRITE
) {
145 *dwDesiredAccess
= FILE_MAP_WRITE
;
146 if (prot
& PROT_EXEC
) {
147 return PAGE_EXECUTE_READWRITE
;
149 return PAGE_READWRITE
;
151 if (prot
& PROT_EXEC
) {
152 *dwDesiredAccess
= FILE_MAP_EXECUTE
;
153 return PAGE_EXECUTE_READ
;
155 *dwDesiredAccess
= FILE_MAP_READ
;
156 return PAGE_READONLY
;
158 if (prot
& PROT_WRITE
) {
159 *dwDesiredAccess
= FILE_MAP_COPY
;
160 return PAGE_WRITECOPY
;
162 if (prot
& PROT_EXEC
) {
163 *dwDesiredAccess
= FILE_MAP_EXECUTE
;
164 return PAGE_EXECUTE_READ
;
167 /* Mapping failed. */
168 *dwDesiredAccess
= 0;
173 void *bt_mmap(void *addr
, size_t length
, int prot
, int flags
, int fd
,
174 off_t offset
, int log_level
)
176 struct mmap_mapping
*mapping
= NULL
;
178 DWORD dwDesiredAccess
;
182 /* Check for a valid fd. */
188 /* We don't support this at the moment. */
189 if (flags
== MAP_FIXED
) {
194 /* Map mmap flags to those of the Windows API. */
195 flProtect
= map_prot_flags(prot
, &dwDesiredAccess
);
196 if (flProtect
== 0) {
201 /* Allocate the mapping struct. */
202 mapping
= mapping_create(log_level
);
204 BT_LOG_WRITE_CUR_LVL(BT_LOG_ERROR
, log_level
, BT_LOG_TAG
,
205 "Failed to allocate mmap mapping.");
210 /* Get a handle from the fd. */
211 handle
= (HANDLE
) _get_osfhandle(fd
);
213 /* Duplicate the handle and store it in 'mapping.file_handle'. */
214 if (!DuplicateHandle(GetCurrentProcess(), handle
, GetCurrentProcess(),
215 &mapping
->file_handle
, 0, FALSE
,
216 DUPLICATE_SAME_ACCESS
)) {
222 * Create a file mapping object with a maximum size
223 * of 'offset' + 'length'.
225 mapping
->map_handle
= CreateFileMapping(mapping
->file_handle
, NULL
,
226 flProtect
, 0, offset
+ length
, NULL
);
227 if (mapping
->map_handle
== 0) {
232 /* Map the requested block starting at 'offset' for 'length' bytes. */
233 mapping_addr
= MapViewOfFile(mapping
->map_handle
, dwDesiredAccess
, 0,
235 if (mapping_addr
== 0) {
236 DWORD dwLastErr
= GetLastError();
237 if (dwLastErr
== ERROR_MAPPED_ALIGNMENT
) {
245 mmap_lock(log_level
);
247 /* If we have never done any mappings, allocate the hashtable. */
248 if (!mmap_mappings
) {
249 mmap_mappings
= g_hash_table_new_full(g_direct_hash
,
250 g_direct_equal
, (GDestroyNotify
) addr_clean
,
251 (GDestroyNotify
) mapping_clean
);
252 if (!mmap_mappings
) {
253 BT_LOGE_STR("Failed to allocate mmap hashtable.");
255 goto error_mutex_unlock
;
259 /* Add the new mapping to the hashtable. */
260 g_hash_table_insert(mmap_mappings
, mapping_addr
, mapping
);
262 mmap_unlock(log_level
);
267 mmap_unlock(log_level
);
269 mapping_clean(mapping
);
274 int bt_munmap(void *addr
, size_t length
)
277 struct mmap_mapping
*mapping
= addr
;
281 log_level
= mapping
->log_level
;
282 mmap_lock(log_level
);
284 /* Check if the mapping exists in the hashtable. */
285 if (g_hash_table_lookup(mmap_mappings
, addr
) == NULL
) {
292 if (!g_hash_table_remove(mmap_mappings
, addr
)) {
293 BT_LOGF_STR("Failed to remove mapping from hashtable.");
298 mmap_unlock(log_level
);