1 /*
2  * Copyright © 2013 Christian Persch
3  *
4  * This library is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU Lesser General Public
6  * License as published by the Free Software Foundation; either
7  * version 2.1 of the License, or (at your option) any later version.
8  *
9  * This library is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
12  * Lesser General Public License for more details.
13  *
14  * You should have received a copy of the GNU Lesser General Public
15  * License along with this library; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
17  */
18 
19 #include "vice.h"
20 
21 #include "vteutils.h"
22 
23 #include <fcntl.h>
24 #include <unistd.h>
25 #include <errno.h>
26 
27 #include <glib.h>
28 
29 /* Temporary define until glibc release catches up */
30 #ifdef __linux__
31 
32 #include <sys/ioctl.h>
33 #include <linux/fs.h>
34 
35 #ifndef O_TMPFILE
36 #ifndef __O_TMPFILE
37 #define __O_TMPFILE     020000000
38 #endif
39 #define O_TMPFILE (__O_TMPFILE | O_DIRECTORY)
40 #endif
41 
42 #endif /* __linux__ */
43 
44 int
_vte_mkstemp(void)45 _vte_mkstemp (void)
46 {
47         int fd;
48         gchar *file_name;
49 
50 #ifdef O_TMPFILE
51         fd = open (g_get_tmp_dir (),
52                    O_TMPFILE | O_EXCL | O_RDWR | O_NOATIME | O_CLOEXEC,
53                    0600);
54         if (fd != -1)
55                 goto done;
56 
57         /* Try again with g_file_open_tmp */
58 #endif
59 
60         fd = g_file_open_tmp ("vteXXXXXX", &file_name, NULL);
61         if (fd == -1)
62                 return -1;
63 
64         unlink (file_name);
65         g_free (file_name);
66 
67 #ifdef O_NOATIME
68         do { } while (fcntl (fd, F_SETFL, O_NOATIME) == -1 && errno == EINTR);
69 #endif
70 
71 #ifdef O_TMPFILE
72  done:
73 #endif
74 
75 #ifdef __linux__
76 {
77         /* Mark the tmpfile as no-cow on file systems that support it.
78          *
79          * (Note that the definition of the ioctls make you think @flags would
80          * be long instead of int, but it turns out that this is not the case;
81          * see http://lwn.net/Articles/575846/ ).
82          */
83         int flags;
84 
85         if (ioctl (fd, FS_IOC_GETFLAGS, &flags) == 0) {
86                 flags |= FS_SECRM_FL | FS_NOATIME_FL | FS_NOCOMP_FL | FS_NOCOW_FL | FS_NODUMP_FL;
87 
88                 ioctl (fd, FS_IOC_SETFLAGS, &flags);
89         }
90 }
91 #endif /* __linux__ */
92 
93         return fd;
94 }
95