/* 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" #include "mysys_err.h" #include <my_sys.h> #ifdef _WIN32 #include <direct.h> /* rmdir */ static int my_win_unlink(const char *name); #endif CREATE_NOSYMLINK_FUNCTION( unlink_nosymlinks(const char *pathname), unlinkat(dfd, filename, 0), unlink(pathname) ); int my_delete(const char *name, myf MyFlags) { int err; DBUG_ENTER("my_delete"); DBUG_PRINT("my",("name %s MyFlags %lu", name, MyFlags)); #ifdef _WIN32 err = my_win_unlink(name); #else if (MyFlags & MY_NOSYMLINKS) err= unlink_nosymlinks(name); else err= unlink(name); #endif if ((MyFlags & MY_IGNORE_ENOENT) && errno == ENOENT) DBUG_RETURN(0); if (err) { my_errno= errno; if (MyFlags & (MY_FAE+MY_WME)) my_error(EE_DELETE, MYF(ME_BELL), name, errno); } else if ((MyFlags & MY_SYNC_DIR) && my_sync_dir_by_file(name, MyFlags)) err= -1; DBUG_RETURN(err); } /* my_delete */ #if defined (_WIN32) /* Delete file. The function also makes best effort to minimize number of errors, where another program (or thread in the current program) has the the same file open. We're using several tricks to prevent the errors, such as - Windows 10 "posix semantics" delete - Avoid the error by using CreateFile() with FILE_FLAG_DELETE_ON_CLOSE, instead of DeleteFile() - If file which is deleted (delete on close) but has not entirely gone, because it is still opened by some app, an attempt to trcreate file with the same name would result in yet another error. The workaround here is renaming a file to unique name. Symbolic link are deleted without renaming. Directories are not deleted. */ #include <my_rdtsc.h> static int my_win_unlink(const char *name) { HANDLE handle= INVALID_HANDLE_VALUE; DWORD attributes; uint last_error; char unique_filename[MAX_PATH + 35]; unsigned long long tsc; /* time stamp counter, for unique filename*/ int retries; DBUG_ENTER("my_win_unlink"); DBUG_INJECT_FILE_SHARING_VIOLATION(name); for (retries= FILE_SHARING_VIOLATION_RETRIES; ; retries--) { attributes= GetFileAttributes(name); if (attributes == INVALID_FILE_ATTRIBUTES) { last_error= GetLastError(); DBUG_PRINT("error", ("GetFileAttributes(%s) failed with %u\n", name, last_error)); goto error; } if (attributes & FILE_ATTRIBUTE_DIRECTORY) { DBUG_PRINT("error", ("can't remove %s - it is a directory\n", name)); errno= EINVAL; DBUG_RETURN(-1); } if (attributes & FILE_ATTRIBUTE_REPARSE_POINT) { /* Symbolic link. Delete link, the not target */ if (!DeleteFile(name)) { last_error= GetLastError(); DBUG_PRINT("error", ("DeleteFile(%s) failed with %u\n", name, last_error)); goto error; } DBUG_RETURN(0); } /* Try Windows 10 method, delete with "posix semantics" (file is not visible, and creating a file with the same name won't fail, even if it the file was open) */ handle= CreateFile(name, DELETE, FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, NULL, OPEN_EXISTING, 0, NULL); if (handle != INVALID_HANDLE_VALUE) { /* 0x3 = FILE_DISPOSITION_FLAG_DELETE | FILE_DISPOSITION_FLAG_POSIX_SEMANTICS */ struct {DWORD _Flags;} disp= {0x3}; BOOL ok= SetFileInformationByHandle( handle, (FILE_INFO_BY_HANDLE_CLASS) 21, &disp, sizeof(disp)); CloseHandle(handle); if (ok) DBUG_RETURN(0); } handle= CreateFile(name, DELETE, 0, NULL, OPEN_EXISTING, FILE_FLAG_DELETE_ON_CLOSE, NULL); if (handle != INVALID_HANDLE_VALUE) { /* We opened file without sharing flags (exclusive), no one else has this file opened, thus it is safe to close handle to remove it. No renaming is necessary. */ CloseHandle(handle); DBUG_RETURN(0); } /* Can't open file exclusively, hence the file must be already opened by someone else. Open it for delete (with all FILE_SHARE flags set), rename to unique name, close. */ handle= CreateFile(name, DELETE, FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, NULL, OPEN_EXISTING, FILE_FLAG_DELETE_ON_CLOSE, NULL); if (handle == INVALID_HANDLE_VALUE) { last_error= GetLastError(); DBUG_PRINT( "error", ("CreateFile(%s) with FILE_FLAG_DELETE_ON_CLOSE failed with %u\n", name, last_error)); goto error; } tsc= my_timer_cycles(); my_snprintf(unique_filename, sizeof(unique_filename), "%s.%llx.deleted", name, tsc); if (!MoveFile(name, unique_filename)) { DBUG_PRINT("warning", ("moving %s to unique filename failed, error %lu\n", name, GetLastError())); } CloseHandle(handle); DBUG_RETURN(0); error: if (last_error != ERROR_SHARING_VIOLATION || retries == 0) { my_osmaperr(last_error); DBUG_RETURN(-1); } DBUG_CLEAR_FILE_SHARING_VIOLATION(); Sleep(FILE_SHARING_VIOLATION_DELAY_MS); } } #endif /* Remove directory recursively. */ int my_rmtree(const char *dir, myf MyFlags) { char path[FN_REFLEN]; char sep[] = { FN_LIBCHAR, 0 }; int err = 0; size_t i; MY_DIR *dir_info = my_dir(dir, MYF(MY_DONT_SORT | MY_WANT_STAT)); if (!dir_info) return 1; for (i = 0; i < dir_info->number_of_files; i++) { FILEINFO *file = dir_info->dir_entry + i; /* Skip "." and ".." */ if (!strcmp(file->name, ".") || !strcmp(file->name, "..")) continue; strxnmov(path, sizeof(path), dir, sep, file->name, NULL); if (!MY_S_ISDIR(file->mystat->st_mode)) { err = my_delete(path, MyFlags); #ifdef _WIN32 /* On Windows, check and possible reset readonly attribute. my_delete(), or DeleteFile does not remove theses files. */ if (err) { DWORD attr = GetFileAttributes(path); if (attr != INVALID_FILE_ATTRIBUTES && (attr & FILE_ATTRIBUTE_READONLY)) { SetFileAttributes(path, attr &~FILE_ATTRIBUTE_READONLY); err = my_delete(path, MyFlags); } } #endif } else err = my_rmtree(path, MyFlags); if (err) break; } my_dirend(dir_info); if (!err) err = rmdir(dir); return err; }