platform_bionic/libc/bionic/sys_statfs.cpp
Elliott Hughes 261bd745ee Support statvfs on API levels before 19.
Split statfs and statvfs. The former has been available forever, and the
latter is implemented in terms of the former. The implementation has
been moved into headers so that it can be used at low API levels.

There's no reason for any Android or Linux code to use statvfs rather
than statfs, but code that needs to build on Darwin too will want to use
statvfs because Darwin's statfs is very spartan.

Bug: https://github.com/android-ndk/ndk/issues/609
Test: treehugger
Change-Id: Icf3d5723a260099fddb2d9f902e3047b0f041647
2019-08-29 21:57:58 -07:00

55 lines
1.8 KiB
C++

/*
* Copyright (C) 2013 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <sys/statfs.h>
// Paper over the fact that 32-bit kernels use fstatfs64/statfs64 with
// an extra argument, but 64-bit kernels don't have the "64" bit suffix or
// the extra size_t argument.
#if defined(__LP64__)
extern "C" int __fstatfs(int, struct statfs*);
extern "C" int __statfs(const char*, struct statfs*);
# define __fstatfs64(fd,size,buf) __fstatfs(fd,buf)
# define __statfs64(path,size,buf) __statfs(path,buf)
#else
extern "C" int __fstatfs64(int, size_t, struct statfs*);
extern "C" int __statfs64(const char*, size_t, struct statfs*);
#endif
// The kernel sets a private ST_VALID flag to signal to the C library
// whether the f_flags field is valid. This flag should not be exposed to
// users of the C library.
#define ST_VALID 0x0020
int fstatfs(int fd, struct statfs* result) {
int rc = __fstatfs64(fd, sizeof(*result), result);
if (rc != 0) {
return rc;
}
result->f_flags &= ~ST_VALID;
return 0;
}
__strong_alias(fstatfs64, fstatfs);
int statfs(const char* path, struct statfs* result) {
int rc = __statfs64(path, sizeof(*result), result);
if (rc != 0) {
return rc;
}
result->f_flags &= ~ST_VALID;
return 0;
}
__strong_alias(statfs64, statfs);