1/*
2 * Copyright (C) 2013 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#include <sys/statvfs.h>
18
19#include <sys/statfs.h>
20
21// Paper over the fact that 32-bit kernels use fstatfs64/statfs64 with an extra argument,
22// but 64-bit kernels don't have the "64" bit suffix or the extra size_t argument.
23#if __LP64__
24extern "C" int __fstatfs(int, struct statfs*);
25extern "C" int __statfs(const char*, struct statfs*);
26#  define __fstatfs64(fd,size,buf) __fstatfs(fd,buf)
27#  define __statfs64(path,size,buf) __statfs(path,buf)
28#else
29extern "C" int __fstatfs64(int, size_t, struct statfs*);
30extern "C" int __statfs64(const char*, size_t, struct statfs*);
31#endif
32
33// The kernel sets a private ST_VALID flag to signal to the C library whether the
34// f_flags field is valid. This flag should not be exposed to users of the C library.
35#define ST_VALID 0x0020
36
37static void __statfs_to_statvfs(const struct statfs& in, struct statvfs* out) {
38  out->f_bsize = in.f_bsize;
39  out->f_frsize = in.f_frsize;
40  out->f_blocks = in.f_blocks;
41  out->f_bfree = in.f_bfree;
42  out->f_bavail = in.f_bavail;
43  out->f_files = in.f_files;
44  out->f_ffree = in.f_ffree;
45  out->f_favail = in.f_ffree;
46  out->f_fsid = in.f_fsid.__val[0] | (static_cast<uint64_t>(in.f_fsid.__val[1]) << 32);
47  out->f_flag = in.f_flags;
48  out->f_namemax = in.f_namelen;
49}
50
51int fstatfs(int fd, struct statfs* result) {
52  int rc = __fstatfs64(fd, sizeof(*result), result);
53  if (rc != 0) {
54    return rc;
55  }
56  result->f_flags &= ~ST_VALID;
57  return 0;
58}
59__strong_alias(fstatfs64, fstatfs);
60
61int statfs(const char* path, struct statfs* result) {
62  int rc = __statfs64(path, sizeof(*result), result);
63  if (rc != 0) {
64    return rc;
65  }
66  result->f_flags &= ~ST_VALID;
67  return 0;
68}
69__strong_alias(statfs64, statfs);
70
71int statvfs(const char* path, struct statvfs* result) {
72  struct statfs tmp;
73  int rc = statfs(path, &tmp);
74  if (rc != 0) {
75    return rc;
76  }
77  __statfs_to_statvfs(tmp, result);
78  return 0;
79}
80__strong_alias(statvfs64, statvfs);
81
82int fstatvfs(int fd, struct statvfs* result) {
83  struct statfs tmp;
84  int rc = fstatfs(fd, &tmp);
85  if (rc != 0) {
86    return rc;
87  }
88  __statfs_to_statvfs(tmp, result);
89  return 0;
90}
91__strong_alias(fstatvfs64, fstatvfs);
92