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Diffstat (limited to 'mysql/mysys/mf_tempfile.c')
| -rw-r--r-- | mysql/mysys/mf_tempfile.c | 140 |
1 files changed, 140 insertions, 0 deletions
diff --git a/mysql/mysys/mf_tempfile.c b/mysql/mysys/mf_tempfile.c new file mode 100644 index 0000000..beeabba --- /dev/null +++ b/mysql/mysys/mf_tempfile.c @@ -0,0 +1,140 @@ +/* Copyright (c) 2000, 2015, 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 02110-1301 USA */ + +#include "mysys_priv.h" +#include <m_string.h> +#include "my_static.h" +#include "mysys_err.h" +#include <errno.h> +#include "my_thread_local.h" + + +/* + @brief + Create a temporary file with unique name in a given directory + + @details + create_temp_file + to pointer to buffer where temporary filename will be stored + dir directory where to create the file + prefix prefix the filename with this + mode Flags to use for my_create/my_open + MyFlags Magic flags + + @return + File descriptor of opened file if success + -1 and sets errno if fails. + + @note + The behaviour of this function differs a lot between + implementation, it's main use is to generate a file with + a name that does not already exist. + + When passing O_TEMPORARY flag in "mode" the file should + be automatically deleted + + The implementation using mkstemp should be considered the + reference implementation when adding a new or modifying an + existing one + +*/ + +File create_temp_file(char *to, const char *dir, const char *prefix, + int mode, myf MyFlags) +{ + File file= -1; +#ifdef _WIN32 + TCHAR path_buf[MAX_PATH-14]; +#endif + + DBUG_ENTER("create_temp_file"); + DBUG_PRINT("enter", ("dir: %s, prefix: %s", dir, prefix)); +#if defined(_WIN32) + + /* + Use GetTempPath to determine path for temporary files. + This is because the documentation for GetTempFileName + has the following to say about this parameter: + "If this parameter is NULL, the function fails." + */ + if (!dir) + { + if(GetTempPath(sizeof(path_buf), path_buf) > 0) + dir = path_buf; + } + /* + Use GetTempFileName to generate a unique filename, create + the file and release it's handle + - uses up to the first three letters from prefix + */ + if (GetTempFileName(dir, prefix, 0, to) == 0) + DBUG_RETURN(-1); + + DBUG_PRINT("info", ("name: %s", to)); + + /* + Open the file without the "open only if file doesn't already exist" + since the file has already been created by GetTempFileName + */ + if ((file= my_open(to, (mode & ~O_EXCL), MyFlags)) < 0) + { + /* Open failed, remove the file created by GetTempFileName */ + int tmp= my_errno(); + (void) my_delete(to, MYF(0)); + set_my_errno(tmp); + } + +#else /* mkstemp() is available on all non-Windows supported platforms. */ + { + char prefix_buff[30]; + uint pfx_len; + File org_file; + + pfx_len= (uint) (my_stpcpy(my_stpnmov(prefix_buff, + prefix ? prefix : "tmp.", + sizeof(prefix_buff)-7),"XXXXXX") - + prefix_buff); + if (!dir && ! (dir =getenv("TMPDIR"))) + dir= DEFAULT_TMPDIR; + if (strlen(dir)+ pfx_len > FN_REFLEN-2) + { + errno=ENAMETOOLONG; + set_my_errno(ENAMETOOLONG); + DBUG_RETURN(file); + } + my_stpcpy(convert_dirname(to,dir,NullS),prefix_buff); + org_file=mkstemp(to); + if (mode & O_TEMPORARY) + (void) my_delete(to, MYF(MY_WME)); + file=my_register_filename(org_file, to, FILE_BY_MKSTEMP, + EE_CANTCREATEFILE, MyFlags); + /* If we didn't manage to register the name, remove the temp file */ + if (org_file >= 0 && file < 0) + { + int tmp=my_errno(); + close(org_file); + (void) my_delete(to, MYF(MY_WME)); + set_my_errno(tmp); + } + } +#endif + if (file >= 0) + { + mysql_mutex_lock(&THR_LOCK_open); + my_tmp_file_created++; + mysql_mutex_unlock(&THR_LOCK_open); + } + DBUG_RETURN(file); +} |