src/lxc/file_utils.h

   1 /* liblxcapi
   2  *
   3  * Copyright © 2018 Christian Brauner <christian.brauner@ubuntu.com>.
   4  * Copyright © 2018 Canonical Ltd.
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15
  16  * You should have received a copy of the GNU Lesser General Public License
  17  * along with this library; if not, write to the Free Software Foundation,
  18  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
  19  */
  20
  21 #ifndef __LXC_FILE_UTILS_H
  22 #define __LXC_FILE_UTILS_H
  23
  24 #include <fcntl.h>
  25 #include <stdbool.h>
  26 #include <stdio.h>
  27 #include <sys/stat.h>
  28 #include <sys/types.h>
  29 #include <sys/uio.h>
  30 #include <sys/vfs.h>
  31 #include <unistd.h>
  32
  33 /* read and write whole files */
  34 extern int lxc_write_to_file(const char *filename, const void *buf,
  35                              size_t count, bool add_newline, mode_t mode);
  36 extern int lxc_writeat(int dirfd, const char *filename, const void *buf,
  37                        size_t count);
  38 extern int lxc_read_from_file(const char *filename, void *buf, size_t count);
  39
  40 /* send and receive buffers completely */
  41 extern ssize_t lxc_write_nointr(int fd, const void *buf, size_t count);
  42 extern ssize_t lxc_send_nointr(int sockfd, void *buf, size_t len, int flags);
  43 extern ssize_t lxc_read_nointr(int fd, void *buf, size_t count);
  44 extern ssize_t lxc_read_nointr_expect(int fd, void *buf, size_t count,
  45                                       const void *expected_buf);
  46 extern ssize_t lxc_read_file_expect(const char *path, void *buf, size_t count,
  47                                       const void *expected_buf);
  48 extern ssize_t lxc_recv_nointr(int sockfd, void *buf, size_t len, int flags);
  49 ssize_t lxc_recvmsg_nointr_iov(int sockfd, struct iovec *iov, size_t iovlen,
  50                                int flags);
  51
  52 extern bool file_exists(const char *f);
  53 extern int print_to_file(const char *file, const char *content);
  54 extern int is_dir(const char *path);
  55 extern int lxc_count_file_lines(const char *fn);
  56 extern int lxc_make_tmpfile(char *template, bool rm);
  57
  58 /* __typeof__ should be safe to use with all compilers. */
  59 typedef __typeof__(((struct statfs *)NULL)->f_type) fs_type_magic;
  60 extern bool has_fs_type(const char *path, fs_type_magic magic_val);
  61 extern bool fhas_fs_type(int fd, fs_type_magic magic_val);
  62 extern bool is_fs_type(const struct statfs *fs, fs_type_magic magic_val);
  63 extern FILE *fopen_cloexec(const char *path, const char *mode);
  64 extern ssize_t lxc_sendfile_nointr(int out_fd, int in_fd, off_t *offset,
  65                                    size_t count);
  66 extern char *file_to_buf(char *path, size_t *length);
  67 extern int fd_to_fd(int from, int to);
  68
  69 #endif /* __LXC_FILE_UTILS_H */