1 /* Emulate fsync on platforms that lack it, primarily Windows and 2 cross-compilers like MinGW. 3 4 This is derived from sqlite3 sources. 5 https://www.sqlite.org/src/finfo?name=src/os_win.c 6 https://www.sqlite.org/copyright.html 7 8 Written by Richard W.M. Jones <rjones.at.redhat.com> 9 10 Copyright (C) 2008-2021 Free Software Foundation, Inc. 11 12 This file is free software: you can redistribute it and/or modify 13 it under the terms of the GNU Lesser General Public License as 14 published by the Free Software Foundation; either version 2.1 of the 15 License, or (at your option) any later version. 16 17 This file is distributed in the hope that it will be useful, 18 but WITHOUT ANY WARRANTY; without even the implied warranty of 19 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 20 GNU Lesser General Public License for more details. 21 22 You should have received a copy of the GNU Lesser General Public License 23 along with this program. If not, see <https://www.gnu.org/licenses/>. */ 24 25 #include <config.h> 26 #include <unistd.h> 27 28 #if defined _WIN32 && ! defined __CYGWIN__ 29 30 /* FlushFileBuffers */ 31 # define WIN32_LEAN_AND_MEAN 32 # include <windows.h> 33 34 # include <errno.h> 35 36 /* Get _get_osfhandle. */ 37 # if GNULIB_MSVC_NOTHROW 38 # include "msvc-nothrow.h" 39 # else 40 # include <io.h> 41 # endif 42 43 int 44 fsync (int fd) /* */ 45 { 46 HANDLE h = (HANDLE) _get_osfhandle (fd); 47 DWORD err; 48 49 if (h == INVALID_HANDLE_VALUE) 50 { 51 errno = EBADF; 52 return -1; 53 } 54 55 if (!FlushFileBuffers (h)) 56 { 57 /* Translate some Windows errors into rough approximations of Unix 58 * errors. MSDN is useless as usual - in this case it doesn't 59 * document the full range of errors. 60 */ 61 err = GetLastError (); 62 switch (err) 63 { 64 case ERROR_ACCESS_DENIED: 65 /* For a read-only handle, fsync should succeed, even though we have 66 no way to sync the access-time changes. */ 67 return 0; 68 69 /* eg. Trying to fsync a tty. */ 70 case ERROR_INVALID_HANDLE: 71 errno = EINVAL; 72 break; 73 74 default: 75 errno = EIO; 76 } 77 return -1; 78 } 79 80 return 0; 81 } 82 83 #else /* !Windows */ 84 85 # error "This platform lacks fsync function, and Gnulib doesn't provide a replacement. This is a bug in Gnulib." 86 87 #endif /* !Windows */