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- /* Copyright (c) 2000, 2021, Oracle and/or its affiliates.
-
- This program is free software; you can redistribute it and/or modify
- it under the terms of the GNU General Public License, version 2.0,
- as published by the Free Software Foundation.
-
- This program is also distributed with certain software (including
- but not limited to OpenSSL) that is licensed under separate terms,
- as designated in a particular file or component or in included license
- documentation. The authors of MySQL hereby grant you an additional
- permission to link the program and your derivative works with the
- separately licensed software that they have included with MySQL.
-
- Without limiting anything contained in the foregoing, this file,
- which is part of C Driver for MySQL (Connector/C), is also subject to the
- Universal FOSS Exception, version 1.0, a copy of which can be found at
- http://oss.oracle.com/licenses/universal-foss-exception.
-
- This program is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- GNU General Public License, version 2.0, for more details.
-
- You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */
-
- #include "mysys_priv.h"
- #include "my_sys.h"
-
- #ifdef HAVE_SYS_MMAN_H
-
- /*
- system msync() only syncs mmap'ed area to fs cache.
- fsync() is required to really sync to disc
- */
- int my_msync(int fd, void *addr, size_t len, int flags)
- {
- msync(addr, len, flags);
- return my_sync(fd, MYF(0));
- }
-
- #elif defined(_WIN32)
-
- static SECURITY_ATTRIBUTES mmap_security_attributes=
- {sizeof(SECURITY_ATTRIBUTES), 0, TRUE};
-
- void *my_mmap(void *addr, size_t len, int prot,
- int flags, File fd, my_off_t offset)
- {
- HANDLE hFileMap;
- LPVOID ptr;
- HANDLE hFile= (HANDLE)my_get_osfhandle(fd);
- DBUG_ENTER("my_mmap");
- DBUG_PRINT("mysys", ("map fd: %d", fd));
-
- if (hFile == INVALID_HANDLE_VALUE)
- DBUG_RETURN(MAP_FAILED);
-
- hFileMap=CreateFileMapping(hFile, &mmap_security_attributes,
- PAGE_READWRITE, 0, (DWORD) len, NULL);
- if (hFileMap == 0)
- DBUG_RETURN(MAP_FAILED);
-
- ptr=MapViewOfFile(hFileMap,
- prot & PROT_WRITE ? FILE_MAP_WRITE : FILE_MAP_READ,
- (DWORD)(offset >> 32), (DWORD)offset, len);
-
- /*
- MSDN explicitly states that it's possible to close File Mapping Object
- even when a view is not unmapped - then the object will be held open
- implicitly until unmap, as every view stores internally a handler of
- a corresponding File Mapping Object
- */
- CloseHandle(hFileMap);
-
- if (ptr)
- {
- DBUG_PRINT("mysys", ("mapped addr: %p", ptr));
- DBUG_RETURN(ptr);
- }
-
- DBUG_RETURN(MAP_FAILED);
- }
-
- int my_munmap(void *addr, size_t len)
- {
- DBUG_ENTER("my_munmap");
- DBUG_PRINT("mysys", ("unmap addr: %p", addr));
- DBUG_RETURN(UnmapViewOfFile(addr) ? 0 : -1);
- }
-
- int my_msync(int fd, void *addr, size_t len, int flags)
- {
- return FlushViewOfFile(addr, len) ? 0 : -1;
- }
-
- #else
- #error "no mmap!"
- #endif
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