129 lines · cpp
1//===-- Linux implementation of pathconf_utils ----------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9// This header must go before limits_macros.h otherwise libc header may choose10// to undefine LINK_MAX.11#include <linux/limits.h> // For LINK_MAX and other limits12 13#include "hdr/limits_macros.h"14#include "hdr/unistd_macros.h"15#include "src/__support/OSUtil/syscall.h" // For internal syscall function.16#include "src/__support/common.h"17#include "src/__support/libc_errno.h"18#include "src/__support/macros/config.h"19#include "src/sys/statvfs/linux/statfs_utils.h"20 21// other linux specific includes22#include <linux/bfs_fs.h>23#if __has_include(<linux/ufs_fs.h>)24#include <linux/ufs_fs.h>25#else26// from https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/27#define UFS_MAGIC 0x0001195428#endif29#include <linux/magic.h> // For common FS magics30 31namespace LIBC_NAMESPACE_DECL {32 33long filesizebits(const statfs_utils::LinuxStatFs &s) {34 switch (s.f_type) {35 case JFFS2_SUPER_MAGIC:36 case MSDOS_SUPER_MAGIC:37 case NCP_SUPER_MAGIC:38 return 32;39 }40 return 64;41}42 43long link_max(const statfs_utils::LinuxStatFs &s) {44 switch (s.f_type) {45 case EXT2_SUPER_MAGIC:46 return 32000;47 case MINIX_SUPER_MAGIC:48 return 250;49 case MINIX2_SUPER_MAGIC:50 return 65530;51 case REISERFS_SUPER_MAGIC:52 return 0xffff - 1000;53 case UFS_MAGIC:54 return 32000;55 }56 return LINK_MAX;57}58 59long symlinks(const statfs_utils::LinuxStatFs &s) {60 switch (s.f_type) {61 case ADFS_SUPER_MAGIC:62 case BFS_MAGIC:63 case CRAMFS_MAGIC:64 case EFS_SUPER_MAGIC:65 case MSDOS_SUPER_MAGIC:66 case QNX4_SUPER_MAGIC:67 return 0;68 }69 return 1;70}71 72long pathconfig(const statfs_utils::LinuxStatFs &s, int name) {73 switch (name) {74 case _PC_LINK_MAX:75 return link_max(s);76 77 case _PC_FILESIZEBITS:78 return filesizebits(s);79 80 case _PC_2_SYMLINKS:81 return symlinks(s);82 83 case _PC_REC_MIN_XFER_SIZE:84 return s.f_bsize;85 86 case _PC_ALLOC_SIZE_MIN:87 case _PC_REC_XFER_ALIGN:88 return s.f_frsize;89 90 case _PC_MAX_CANON:91 return _POSIX_MAX_CANON;92 93 case _PC_MAX_INPUT:94 return _POSIX_MAX_INPUT;95 96 case _PC_NAME_MAX:97 return s.f_namelen;98 99 case _PC_PATH_MAX:100 return _POSIX_PATH_MAX;101 102 case _PC_PIPE_BUF:103 return _POSIX_PIPE_BUF;104 105 case _PC_CHOWN_RESTRICTED:106 return _POSIX_CHOWN_RESTRICTED;107 108 case _PC_NO_TRUNC:109 return _POSIX_NO_TRUNC;110 111 case _PC_VDISABLE:112 return _POSIX_VDISABLE;113 114 case _PC_ASYNC_IO:115 case _PC_PRIO_IO:116 case _PC_REC_INCR_XFER_SIZE:117 case _PC_REC_MAX_XFER_SIZE:118 case _PC_SYMLINK_MAX:119 case _PC_SYNC_IO:120 return -1;121 122 default:123 libc_errno = EINVAL;124 return -1;125 }126}127 128} // namespace LIBC_NAMESPACE_DECL129