src/utils.h

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2
   3 #ifndef __LXCFS_UTILS_H
   4 #define __LXCFS_UTILS_H
   5
   6 #include "config.h"
   7
   8 #include <signal.h>
   9 #include <stdbool.h>
  10 #include <sys/socket.h>
  11 #include <sys/types.h>
  12 #include <sys/un.h>
  13 #include <sys/syscall.h>
  14 #include <unistd.h>
  15
  16 #include "lxcfs_fuse.h"
  17
  18 #include "macro.h"
  19 #include "syscall_numbers.h"
  20
  21 /* Reserve buffer size to account for file size changes. */
  22 #define BUF_RESERVE_SIZE 512
  23
  24 #define SEND_CREDS_OK 0
  25 #define SEND_CREDS_NOTSK 1
  26 #define SEND_CREDS_FAIL 2
  27
  28 struct file_info;
  29
  30 __attribute__((__format__(__printf__, 4, 5))) extern char *must_strcat(char **src, size_t *sz, size_t *asz, const char *format, ...);
  31 extern bool is_shared_pidns(pid_t pid);
  32 extern int preserve_ns(const int pid, const char *ns);
  33 extern void do_release_file_info(struct fuse_file_info *fi);
  34 extern bool recv_creds(int sock, struct ucred *cred, char *v);
  35 extern int send_creds(int sock, struct ucred *cred, char v, bool pingfirst);
  36 extern bool wait_for_sock(int sock, int timeout);
  37 extern int read_file_fuse(const char *path, char *buf, size_t size,
  38                           struct file_info *d);
  39 extern int read_file_fuse_with_offset(const char *path, char *buf, size_t size,
  40                                       off_t offset, struct file_info *d);
  41 extern void prune_init_slice(char *cg);
  42 extern int wait_for_pid(pid_t pid);
  43
  44 #if !HAVE_PIDFD_OPEN
  45 static inline int pidfd_open(pid_t pid, unsigned int flags)
  46 {
  47         return syscall(__NR_pidfd_open, pid, flags);
  48 }
  49 #endif
  50
  51 #if !HAVE_PIDFD_SEND_SIGNAL
  52 static inline int pidfd_send_signal(int pidfd, int sig, siginfo_t *info,
  53                                     unsigned int flags)
  54 {
  55         return syscall(__NR_pidfd_send_signal, pidfd, sig, info, flags);
  56 }
  57 #endif
  58
  59 extern FILE *fopen_cached(const char *path, const char *mode,
  60                           void **caller_freed_buffer);
  61 extern FILE *fdopen_cached(int fd, const char *mode, void **caller_freed_buffer);
  62 extern DIR *opendir_flags(const char *path, int oflags);
  63 extern ssize_t write_nointr(int fd, const void *buf, size_t count);
  64 extern int safe_uint64(const char *numstr, uint64_t *converted, int base);
  65 extern int safe_uint32(const char *numstr, uint32_t *converted, int base);
  66 extern char *trim_whitespace_in_place(char *buffer);
  67
  68 static inline bool file_exists(const char *f)
  69 {
  70         struct stat statbuf;
  71
  72         return stat(f, &statbuf) == 0;
  73 }
  74
  75 #define PROTECT_OPEN_WITH_TRAILING_SYMLINKS (O_CLOEXEC | O_NOCTTY | O_RDONLY)
  76 #define PROTECT_OPEN (PROTECT_OPEN_WITH_TRAILING_SYMLINKS | O_NOFOLLOW)
  77 extern char *read_file_at(int dfd, const char *fnam, unsigned int o_flags);
  78
  79 #endif /* __LXCFS_UTILS_H */