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/*
* Copyright (C) 2008 The Android Open Source Project
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <unistd.h>
#include <errno.h>
#include <sys/limits.h>
#include <sys/vfs.h>
static long __filesizebits(const struct statfs& s) {
switch (s.f_type) {
case JFFS2_SUPER_MAGIC:
case MSDOS_SUPER_MAGIC:
case NCP_SUPER_MAGIC:
return 32;
}
// There won't be any new 32-bit file systems.
return 64;
}
static long __link_max(const struct statfs& s) {
// These constant values were taken from kernel headers.
// They're not available in uapi headers.
switch (s.f_type) {
case EXT2_SUPER_MAGIC:
return 32000;
case MINIX_SUPER_MAGIC:
return 250;
case MINIX2_SUPER_MAGIC:
return 65530;
case REISERFS_SUPER_MAGIC:
return 0xffff - 1000;
case UFS_MAGIC:
return 32000;
}
return LINK_MAX;
}
static long __2_symlinks(const struct statfs& s) {
switch (s.f_type) {
case ADFS_SUPER_MAGIC:
case BFS_MAGIC:
case CRAMFS_MAGIC:
case EFS_SUPER_MAGIC:
case MSDOS_SUPER_MAGIC:
case QNX4_SUPER_MAGIC:
return 0;
}
return 1;
}
static long __pathconf(const struct statfs& s, int name) {
switch (name) {
case _PC_FILESIZEBITS:
return __filesizebits(s);
case _PC_LINK_MAX:
return __link_max(s);
case _PC_MAX_CANON:
return MAX_CANON;
case _PC_MAX_INPUT:
return MAX_INPUT;
case _PC_NAME_MAX:
return s.f_namelen;
case _PC_PATH_MAX:
return PATH_MAX;
case _PC_PIPE_BUF:
return PIPE_BUF;
case _PC_2_SYMLINKS:
return __2_symlinks(s);
case _PC_ALLOC_SIZE_MIN: /* fall through */
case _PC_REC_XFER_ALIGN:
return s.f_frsize;
case _PC_REC_MIN_XFER_SIZE:
return s.f_bsize;
#if 0
case _PC_REC_INCR_XFER_SIZE:
case _PC_REC_MAX_XFER_SIZE:
#endif
case _PC_SYMLINK_MAX:
return -1; /* no limit */
case _PC_CHOWN_RESTRICTED:
return _POSIX_CHOWN_RESTRICTED;
case _PC_NO_TRUNC:
return _POSIX_NO_TRUNC;
case _PC_VDISABLE:
return _POSIX_VDISABLE;
case _PC_ASYNC_IO:
return -1;
case _PC_PRIO_IO:
return -1;
case _PC_SYNC_IO:
return -1;
default:
errno = EINVAL;
return -1;
}
}
long pathconf(const char* path, int name) {
struct statfs sb;
if (statfs(path, &sb) == -1) {
return -1;
}
return __pathconf(sb, name);
}
long fpathconf(int fd, int name) {
struct statfs sb;
if (fstatfs(fd, &sb) == -1) {
return -1;
}
return __pathconf(sb, name);
}
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