1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
|
/* Copyright (c) 2000, 2013, 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 <m_string.h>
#include "my_static.h"
#include "mysys_err.h"
#include <errno.h>
#ifdef HAVE_PATHS_H
#include <paths.h>
#endif
#ifdef HAVE_MKOSTEMP
#define mkstemp(A) mkostemp(A, O_CLOEXEC)
#endif
/*
@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 MY_TEMPORARY flag in MyFlags the file is automatically deleted
"mode" bits that always must be used for newly created files with
unique file names (O_EXCL | O_TRUNC | O_CREAT | O_RDWR) are added
automatically, and shouldn't be specified by the caller.
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;
DBUG_ENTER("create_temp_file");
DBUG_PRINT("enter", ("dir: %s, prefix: %s", dir ? dir : "(null)", prefix));
DBUG_ASSERT((mode & (O_EXCL | O_TRUNC | O_CREAT | O_RDWR)) == 0);
mode|= O_TRUNC | O_CREAT | O_RDWR; /* not O_EXCL, see Windows code below */
#ifdef _WIN32
{
TCHAR path_buf[MAX_PATH-14];
/*
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));
if (MyFlags & MY_TEMPORARY)
mode|= O_SHORT_LIVED | O_TEMPORARY;
/*
Open the file without O_EXCL flag
since the file has already been created by GetTempFileName
*/
if ((file= my_open(to, mode, MyFlags)) < 0)
{
/* Open failed, remove the file created by GetTempFileName */
int tmp= my_errno;
(void) my_delete(to, MYF(0));
my_errno= tmp;
}
}
#elif defined(HAVE_MKSTEMP)
if (!dir && ! (dir =getenv("TMPDIR")))
dir= DEFAULT_TMPDIR;
#ifdef O_TMPFILE
{
static int O_TMPFILE_works= 1;
if ((MyFlags & MY_TEMPORARY) && O_TMPFILE_works)
{
/* explictly don't use O_EXCL here has it has a different
meaning with O_TMPFILE
*/
if ((file= open(dir, (mode & ~O_CREAT) | O_TMPFILE | O_CLOEXEC,
S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP)) >= 0)
{
my_snprintf(to, FN_REFLEN, "%s/#sql/fd=%d", dir, file);
file=my_register_filename(file, to, FILE_BY_O_TMPFILE,
EE_CANTCREATEFILE, MyFlags);
}
else if (errno == EOPNOTSUPP || errno == EINVAL)
{
my_printf_error(EE_CANTCREATEFILE, "O_TMPFILE is not supported on %s "
"(disabling future attempts)",
MYF(ME_NOTE | ME_ERROR_LOG_ONLY), dir);
O_TMPFILE_works= 0;
}
}
}
if (file == -1)
#endif /* O_TMPFILE */
{
char prefix_buff[30];
uint pfx_len;
File org_file;
pfx_len= (uint) (strmov(strnmov(prefix_buff,
prefix ? prefix : "tmp.",
sizeof(prefix_buff)-7),"XXXXXX") -
prefix_buff);
if (strlen(dir)+ pfx_len > FN_REFLEN-2)
{
errno=my_errno= ENAMETOOLONG;
DBUG_RETURN(file);
}
strmov(convert_dirname(to,dir,NullS),prefix_buff);
org_file=mkstemp(to);
if (org_file >= 0 && (MyFlags & MY_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));
my_errno=tmp;
}
}
#else
#error No implementation found for create_temp_file
#endif
if (file >= 0)
statistic_increment(my_tmp_file_created,&THR_LOCK_open);
DBUG_RETURN(file);
}
|
