From 8fcde01280adcbd07e8205b91ac52b06305b6208 Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Mon, 26 Oct 2015 22:01:44 +0100 Subject: util-lib: split stat()/statfs()/stavfs() related calls into stat-util.[ch] --- src/basic/stat-util.c | 216 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 216 insertions(+) create mode 100644 src/basic/stat-util.c (limited to 'src/basic/stat-util.c') diff --git a/src/basic/stat-util.c b/src/basic/stat-util.c new file mode 100644 index 0000000000..3bc66b3be7 --- /dev/null +++ b/src/basic/stat-util.c @@ -0,0 +1,216 @@ +/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ + +/*** + This file is part of systemd. + + Copyright 2010-2012 Lennart Poettering + + systemd is free software; you can redistribute it and/or modify it + under the terms of the GNU Lesser General Public License as published by + the Free Software Foundation; either version 2.1 of the License, or + (at your option) any later version. + + systemd is distributed in the hope that it will be useful, but + WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public License + along with systemd; If not, see . +***/ + +#include +#include +#include +#include + +#include "dirent-util.h" +#include "fd-util.h" +#include "macro.h" +#include "missing.h" +#include "stat-util.h" +#include "string-util.h" + +int is_symlink(const char *path) { + struct stat info; + + assert(path); + + if (lstat(path, &info) < 0) + return -errno; + + return !!S_ISLNK(info.st_mode); +} + +int is_dir(const char* path, bool follow) { + struct stat st; + int r; + + assert(path); + + if (follow) + r = stat(path, &st); + else + r = lstat(path, &st); + if (r < 0) + return -errno; + + return !!S_ISDIR(st.st_mode); +} + +int is_device_node(const char *path) { + struct stat info; + + assert(path); + + if (lstat(path, &info) < 0) + return -errno; + + return !!(S_ISBLK(info.st_mode) || S_ISCHR(info.st_mode)); +} + +int dir_is_empty(const char *path) { + _cleanup_closedir_ DIR *d; + struct dirent *de; + + d = opendir(path); + if (!d) + return -errno; + + FOREACH_DIRENT(de, d, return -errno) + return 0; + + return 1; +} + +bool null_or_empty(struct stat *st) { + assert(st); + + if (S_ISREG(st->st_mode) && st->st_size <= 0) + return true; + + /* We don't want to hardcode the major/minor of /dev/null, + * hence we do a simpler "is this a device node?" check. */ + + if (S_ISCHR(st->st_mode) || S_ISBLK(st->st_mode)) + return true; + + return false; +} + +int null_or_empty_path(const char *fn) { + struct stat st; + + assert(fn); + + if (stat(fn, &st) < 0) + return -errno; + + return null_or_empty(&st); +} + +int null_or_empty_fd(int fd) { + struct stat st; + + assert(fd >= 0); + + if (fstat(fd, &st) < 0) + return -errno; + + return null_or_empty(&st); +} + +int path_is_read_only_fs(const char *path) { + struct statvfs st; + + assert(path); + + if (statvfs(path, &st) < 0) + return -errno; + + if (st.f_flag & ST_RDONLY) + return true; + + /* On NFS, statvfs() might not reflect whether we can actually + * write to the remote share. Let's try again with + * access(W_OK) which is more reliable, at least sometimes. */ + if (access(path, W_OK) < 0 && errno == EROFS) + return true; + + return false; +} + +int path_is_os_tree(const char *path) { + char *p; + int r; + + assert(path); + + /* We use /usr/lib/os-release as flag file if something is an OS */ + p = strjoina(path, "/usr/lib/os-release"); + r = access(p, F_OK); + if (r >= 0) + return 1; + + /* Also check for the old location in /etc, just in case. */ + p = strjoina(path, "/etc/os-release"); + r = access(p, F_OK); + + return r >= 0; +} + +int files_same(const char *filea, const char *fileb) { + struct stat a, b; + + assert(filea); + assert(fileb); + + if (stat(filea, &a) < 0) + return -errno; + + if (stat(fileb, &b) < 0) + return -errno; + + return a.st_dev == b.st_dev && + a.st_ino == b.st_ino; +} + +bool is_fs_type(const struct statfs *s, statfs_f_type_t magic_value) { + assert(s); + assert_cc(sizeof(statfs_f_type_t) >= sizeof(s->f_type)); + + return F_TYPE_EQUAL(s->f_type, magic_value); +} + +int fd_check_fstype(int fd, statfs_f_type_t magic_value) { + struct statfs s; + + if (fstatfs(fd, &s) < 0) + return -errno; + + return is_fs_type(&s, magic_value); +} + +int path_check_fstype(const char *path, statfs_f_type_t magic_value) { + _cleanup_close_ int fd = -1; + + fd = open(path, O_RDONLY); + if (fd < 0) + return -errno; + + return fd_check_fstype(fd, magic_value); +} + +bool is_temporary_fs(const struct statfs *s) { + return is_fs_type(s, TMPFS_MAGIC) || + is_fs_type(s, RAMFS_MAGIC); +} + +int fd_is_temporary_fs(int fd) { + struct statfs s; + + if (fstatfs(fd, &s) < 0) + return -errno; + + return is_temporary_fs(&s); +} -- cgit v1.2.3-54-g00ecf