1 /*
2 can_clone_file.c -- does the current filesystem support cloning
3 Copyright (C) 1999-2018 Dieter Baron and Thomas Klausner
4
5 This file is part of libzip, a library to manipulate ZIP archives.
6 The authors can be contacted at <libzip@nih.at>
7
8 Redistribution and use in source and binary forms, with or without
9 modification, are permitted provided that the following conditions
10 are met:
11 1. Redistributions of source code must retain the above copyright
12 notice, this list of conditions and the following disclaimer.
13 2. Redistributions in binary form must reproduce the above copyright
14 notice, this list of conditions and the following disclaimer in
15 the documentation and/or other materials provided with the
16 distribution.
17 3. The names of the authors may not be used to endorse or promote
18 products derived from this software without specific prior
19 written permission.
20
21 THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS
22 OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
23 WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY
25 DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
27 GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28 INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
29 IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
30 OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
31 IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32 */
33
34 #include <errno.h>
35 #include <stdio.h>
36 #include <stdlib.h>
37 #include <string.h>
38
39 #include "config.h"
40
41 #ifdef HAVE_CLONEFILE
42 #include <sys/attr.h>
43 #include <sys/mount.h>
44 #include <sys/param.h>
45 #include <unistd.h>
46 #elif defined(HAVE_FICLONERANGE)
47 #include <linux/fs.h>
48 #include <sys/ioctl.h>
49 #include <unistd.h>
50 #endif
51
52 int
main(int argc,char * argv[])53 main(int argc, char *argv[]) {
54 #ifdef HAVE_CLONEFILE
55 struct statfs fs;
56 struct attrlist attribute_list;
57 struct {
58 uint32_t size;
59 vol_capabilities_attr_t capabilities;
60 } volume_attributes;
61
62 if (statfs(".", &fs) < 0) {
63 fprintf(stderr, "%s: can't get mount point of current directory: %s\n", argv[0], strerror(errno));
64 exit(1);
65 }
66
67 /* Not all volumes support clonefile(). A volume can be tested for
68 clonefile() support by using getattrlist(2) to get the volume
69 capabilities attribute ATTR_VOL_CAPABILITIES, and then testing the
70 VOL_CAP_INT_CLONE flag. */
71
72 memset(&attribute_list, 0, sizeof(attribute_list));
73 attribute_list.bitmapcount = ATTR_BIT_MAP_COUNT;
74 attribute_list.volattr = ATTR_VOL_INFO | ATTR_VOL_CAPABILITIES;
75 memset(&volume_attributes, 0, sizeof(volume_attributes));
76
77 if (getattrlist(fs.f_mntonname, &attribute_list, &volume_attributes, sizeof(volume_attributes), 0) < 0) {
78 fprintf(stderr, "%s: can't get volume capabilities of '%s': %s\n", argv[0], fs.f_mntonname, strerror(errno));
79 exit(1);
80 }
81
82 if (volume_attributes.capabilities.capabilities[VOL_CAPABILITIES_INTERFACES] & VOL_CAP_INT_CLONE) {
83 exit(0);
84 }
85 #elif defined(HAVE_FICLONERANGE)
86 char namea[32] = "a.fioclone.XXXXXX";
87 char nameb[32] = "b.fioclone.XXXXXX";
88 int fda, fdb, ret;
89 struct file_clone_range range;
90
91 if ((fda = mkstemp(namea)) < 0) {
92 fprintf(stderr, "can't create temp file a: %s\n", strerror(errno));
93 exit(1);
94 }
95 if ((fdb = mkstemp(nameb)) < 0) {
96 fprintf(stderr, "can't create temp file b: %s\n", strerror(errno));
97 (void)close(fda);
98 (void)remove(namea);
99 exit(1);
100 }
101 if (write(fda, "test\n", 5) < 0) {
102 fprintf(stderr, "can't write temp file a: %s\n", strerror(errno));
103 (void)close(fda);
104 (void)remove(namea);
105 close(fdb);
106 (void)remove(nameb);
107 exit(1);
108 }
109 range.src_fd = fda;
110 range.src_offset = 0;
111 range.src_length = 0;
112 range.dest_offset = 0;
113 ret = ioctl(fdb, FICLONERANGE, &range);
114 (void)close(fda);
115 (void)close(fdb);
116 (void)remove(namea);
117 (void)remove(nameb);
118 if (ret >= 0) {
119 exit(0);
120 }
121 #endif
122
123 exit(1);
124 }
125