From 06eaf7232e9a920468c0f8d74dcf2fe8b555501c Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sat, 13 Apr 2024 14:24:36 +0200 Subject: Adding upstream version 1:10.11.6. Signed-off-by: Daniel Baumann --- mysys/my_mmap.c | 105 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 105 insertions(+) create mode 100644 mysys/my_mmap.c (limited to 'mysys/my_mmap.c') diff --git a/mysys/my_mmap.c b/mysys/my_mmap.c new file mode 100644 index 00000000..e04f4add --- /dev/null +++ b/mysys/my_mmap.c @@ -0,0 +1,105 @@ +/* Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; version 2 of the License. + + 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 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 02110-1335 USA */ + +#include "mysys_priv.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) + +#ifndef FILE_DAX_VOLUME +#define FILE_DAX_VOLUME 0x20000000 +#endif + +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 (flags & MAP_SYNC) + { + DWORD filesystemFlags; + if (!GetVolumeInformationByHandleW(hFile, NULL, 0, NULL, NULL, + &filesystemFlags, NULL, 0) || + !(filesystemFlags & FILE_DAX_VOLUME)) + { + UnmapViewOfFile(ptr); + ptr= NULL; + } + } + + 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) && + FlushFileBuffers(my_get_osfhandle(fd)) ? 0 : -1; +} + +#else +#warning "no mmap!" +#endif + -- cgit v1.2.3