| 1 | /* |
| 2 | * compat/compat_mman.h |
| 3 | * |
| 4 | * Copyright (C) 2013 JP Ikaheimonen <jp_ikaheimonen@mentor.com> |
| 5 | * 2016 Michael Jeanson <mjeanson@efficios.com> |
| 6 | * |
| 7 | * These sources are based on ftp://g.oswego.edu/pub/misc/malloc.c |
| 8 | * file by Doug Lea, released to the public domain. |
| 9 | * |
| 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: |
| 16 | * |
| 17 | * The above copyright notice and this permission notice shall be included in |
| 18 | * all copies or substantial portions of the Software. |
| 19 | * |
| 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 |
| 26 | * SOFTWARE. |
| 27 | */ |
| 28 | |
| 29 | #define BT_LOG_TAG "COMPAT-MMAN" |
| 30 | #include "logging.h" |
| 31 | |
| 32 | #ifdef __APPLE__ |
| 33 | /* |
| 34 | * On macOS, we need a dummy symbol so that the linker won't |
| 35 | * complain of an empty table of contents. |
| 36 | */ |
| 37 | BT_HIDDEN |
| 38 | int bt_mman_dummy_symbol; |
| 39 | #endif /* __APPLE__ */ |
| 40 | |
| 41 | #ifdef __MINGW32__ |
| 42 | |
| 43 | #include <errno.h> |
| 44 | #include <io.h> |
| 45 | #include <pthread.h> |
| 46 | #include <stdlib.h> |
| 47 | #include <windows.h> |
| 48 | #include <babeltrace/compat/mman-internal.h> |
| 49 | |
| 50 | struct mmap_mapping { |
| 51 | /* The duplicated handle. */ |
| 52 | HANDLE file_handle; |
| 53 | /* Handle returned by CreateFileMapping. */ |
| 54 | HANDLE map_handle; |
| 55 | }; |
| 56 | |
| 57 | static |
| 58 | GHashTable *mmap_mappings = NULL; |
| 59 | |
| 60 | /* |
| 61 | * This mutex protects the hashtable of memory mappings. |
| 62 | */ |
| 63 | static pthread_mutex_t mmap_mutex = PTHREAD_MUTEX_INITIALIZER; |
| 64 | |
| 65 | static |
| 66 | struct mmap_mapping *mapping_create(void) |
| 67 | { |
| 68 | struct mmap_mapping *mapping; |
| 69 | |
| 70 | mapping = malloc(sizeof(struct mmap_mapping)); |
| 71 | if (mapping != NULL) { |
| 72 | mapping->file_handle = NULL; |
| 73 | mapping->map_handle = NULL; |
| 74 | } |
| 75 | |
| 76 | return mapping; |
| 77 | } |
| 78 | |
| 79 | static |
| 80 | void mapping_clean(struct mmap_mapping *mapping) |
| 81 | { |
| 82 | if (mapping) { |
| 83 | if (!CloseHandle(mapping->map_handle)) { |
| 84 | BT_LOGF_STR("Failed to close mmap map_handle."); |
| 85 | abort(); |
| 86 | } |
| 87 | if (!CloseHandle(mapping->file_handle)) { |
| 88 | BT_LOGF_STR("Failed to close mmap file_handle."); |
| 89 | abort(); |
| 90 | } |
| 91 | free(mapping); |
| 92 | mapping = NULL; |
| 93 | } |
| 94 | } |
| 95 | |
| 96 | static |
| 97 | void addr_clean(void *addr) |
| 98 | { |
| 99 | /* Cleanup of handles should never fail. */ |
| 100 | if (!UnmapViewOfFile(addr)) { |
| 101 | BT_LOGF_STR("Failed to unmap mmap mapping."); |
| 102 | abort(); |
| 103 | } |
| 104 | } |
| 105 | |
| 106 | static |
| 107 | void mmap_lock(void) |
| 108 | { |
| 109 | if (pthread_mutex_lock(&mmap_mutex)) { |
| 110 | BT_LOGF_STR("Failed to acquire mmap_mutex."); |
| 111 | abort(); |
| 112 | } |
| 113 | } |
| 114 | |
| 115 | static |
| 116 | void mmap_unlock(void) |
| 117 | { |
| 118 | if (pthread_mutex_unlock(&mmap_mutex)) { |
| 119 | BT_LOGF_STR("Failed to release mmap_mutex."); |
| 120 | abort(); |
| 121 | } |
| 122 | } |
| 123 | |
| 124 | /* |
| 125 | * Convert mmap memory protection flags to CreateFileMapping page protection |
| 126 | * flag and MapViewOfFile desired access flag. |
| 127 | */ |
| 128 | static |
| 129 | DWORD map_prot_flags(int prot, DWORD *dwDesiredAccess) |
| 130 | { |
| 131 | if (prot & PROT_READ) { |
| 132 | if (prot & PROT_WRITE) { |
| 133 | *dwDesiredAccess = FILE_MAP_WRITE; |
| 134 | if (prot & PROT_EXEC) { |
| 135 | return PAGE_EXECUTE_READWRITE; |
| 136 | } |
| 137 | return PAGE_READWRITE; |
| 138 | } |
| 139 | if (prot & PROT_EXEC) { |
| 140 | *dwDesiredAccess = FILE_MAP_EXECUTE; |
| 141 | return PAGE_EXECUTE_READ; |
| 142 | } |
| 143 | *dwDesiredAccess = FILE_MAP_READ; |
| 144 | return PAGE_READONLY; |
| 145 | } |
| 146 | if (prot & PROT_WRITE) { |
| 147 | *dwDesiredAccess = FILE_MAP_COPY; |
| 148 | return PAGE_WRITECOPY; |
| 149 | } |
| 150 | if (prot & PROT_EXEC) { |
| 151 | *dwDesiredAccess = FILE_MAP_EXECUTE; |
| 152 | return PAGE_EXECUTE_READ; |
| 153 | } |
| 154 | |
| 155 | /* Mapping failed. */ |
| 156 | *dwDesiredAccess = 0; |
| 157 | return 0; |
| 158 | } |
| 159 | |
| 160 | BT_HIDDEN |
| 161 | void *bt_mmap(void *addr, size_t length, int prot, int flags, int fd, |
| 162 | off_t offset) |
| 163 | { |
| 164 | struct mmap_mapping *mapping = NULL; |
| 165 | void *mapping_addr; |
| 166 | DWORD dwDesiredAccess; |
| 167 | DWORD flProtect; |
| 168 | HANDLE handle; |
| 169 | |
| 170 | /* Check for a valid fd. */ |
| 171 | if (fd == -1) { |
| 172 | _set_errno(EBADF); |
| 173 | goto error; |
| 174 | } |
| 175 | |
| 176 | /* We don't support this at the moment. */ |
| 177 | if (flags == MAP_FIXED) { |
| 178 | _set_errno(ENOTSUP); |
| 179 | goto error; |
| 180 | } |
| 181 | |
| 182 | /* Map mmap flags to those of the Windows API. */ |
| 183 | flProtect = map_prot_flags(prot, &dwDesiredAccess); |
| 184 | if (flProtect == 0) { |
| 185 | _set_errno(EINVAL); |
| 186 | goto error; |
| 187 | } |
| 188 | |
| 189 | /* Allocate the mapping struct. */ |
| 190 | mapping = mapping_create(); |
| 191 | if (!mapping) { |
| 192 | BT_LOGE_STR("Failed to allocate mmap mapping."); |
| 193 | _set_errno(ENOMEM); |
| 194 | goto error; |
| 195 | } |
| 196 | |
| 197 | /* Get a handle from the fd. */ |
| 198 | handle = (HANDLE) _get_osfhandle(fd); |
| 199 | |
| 200 | /* Duplicate the handle and store it in 'mapping.file_handle'. */ |
| 201 | if (!DuplicateHandle(GetCurrentProcess(), handle, GetCurrentProcess(), |
| 202 | &mapping->file_handle, 0, FALSE, |
| 203 | DUPLICATE_SAME_ACCESS)) { |
| 204 | _set_errno(ENOMEM); |
| 205 | goto error; |
| 206 | } |
| 207 | |
| 208 | /* |
| 209 | * Create a file mapping object with a maximum size |
| 210 | * of 'offset' + 'length'. |
| 211 | */ |
| 212 | mapping->map_handle = CreateFileMapping(mapping->file_handle, NULL, |
| 213 | flProtect, 0, offset + length, NULL); |
| 214 | if (mapping->map_handle == 0) { |
| 215 | _set_errno(EACCES); |
| 216 | goto error; |
| 217 | } |
| 218 | |
| 219 | /* Map the requested block starting at 'offset' for 'length' bytes. */ |
| 220 | mapping_addr = MapViewOfFile(mapping->map_handle, dwDesiredAccess, 0, |
| 221 | offset, length); |
| 222 | if (mapping_addr == 0) { |
| 223 | DWORD dwLastErr = GetLastError(); |
| 224 | if (dwLastErr == ERROR_MAPPED_ALIGNMENT) { |
| 225 | _set_errno(EINVAL); |
| 226 | } else { |
| 227 | _set_errno(EACCES); |
| 228 | } |
| 229 | goto error; |
| 230 | } |
| 231 | |
| 232 | mmap_lock(); |
| 233 | |
| 234 | /* If we have never done any mappings, allocate the hashtable. */ |
| 235 | if (!mmap_mappings) { |
| 236 | mmap_mappings = g_hash_table_new_full(g_direct_hash, |
| 237 | g_direct_equal, (GDestroyNotify) addr_clean, |
| 238 | (GDestroyNotify) mapping_clean); |
| 239 | if (!mmap_mappings) { |
| 240 | BT_LOGE_STR("Failed to allocate mmap hashtable."); |
| 241 | _set_errno(ENOMEM); |
| 242 | goto error_mutex_unlock; |
| 243 | } |
| 244 | } |
| 245 | |
| 246 | /* Add the new mapping to the hashtable. */ |
| 247 | if (!g_hash_table_insert(mmap_mappings, mapping_addr, mapping)) { |
| 248 | BT_LOGF_STR("Failed to insert mapping in the hashtable."); |
| 249 | abort(); |
| 250 | } |
| 251 | |
| 252 | mmap_unlock(); |
| 253 | |
| 254 | return mapping_addr; |
| 255 | |
| 256 | error_mutex_unlock: |
| 257 | mmap_unlock(); |
| 258 | error: |
| 259 | mapping_clean(mapping); |
| 260 | return MAP_FAILED; |
| 261 | } |
| 262 | |
| 263 | BT_HIDDEN |
| 264 | int bt_munmap(void *addr, size_t length) |
| 265 | { |
| 266 | int ret = 0; |
| 267 | |
| 268 | mmap_lock(); |
| 269 | |
| 270 | /* Check if the mapping exists in the hashtable. */ |
| 271 | if (g_hash_table_lookup(mmap_mappings, addr) == NULL) { |
| 272 | _set_errno(EINVAL); |
| 273 | ret = -1; |
| 274 | goto end; |
| 275 | } |
| 276 | |
| 277 | /* Remove it. */ |
| 278 | if (!g_hash_table_remove(mmap_mappings, addr)) { |
| 279 | BT_LOGF_STR("Failed to remove mapping from hashtable."); |
| 280 | abort(); |
| 281 | } |
| 282 | |
| 283 | end: |
| 284 | mmap_unlock(); |
| 285 | return ret; |
| 286 | } |
| 287 | |
| 288 | #endif |