gdb/common/filestuff.h

   1 /* Low-level file-handling.
   2    Copyright (C) 2012-2018 Free Software Foundation, Inc.
   3
   4    This file is part of GDB.
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program 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
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  18
  19 #ifndef FILESTUFF_H
  20 #define FILESTUFF_H
  21
  22 #include <dirent.h>
  23
  24 /* Note all the file descriptors which are open when this is called.
  25    These file descriptors will not be closed by close_most_fds.  */
  26
  27 extern void notice_open_fds (void);
  28
  29 /* Mark a file descriptor as inheritable across an exec.  */
  30
  31 extern void mark_fd_no_cloexec (int fd);
  32
  33 /* Mark a file descriptor as no longer being inheritable across an
  34    exec.  This is only meaningful when FD was previously passed to
  35    mark_fd_no_cloexec.  */
  36
  37 extern void unmark_fd_no_cloexec (int fd);
  38
  39 /* Close all open file descriptors other than those marked by
  40    'notice_open_fds', and stdin, stdout, and stderr.  Errors that
  41    occur while closing are ignored.  */
  42
  43 extern void close_most_fds (void);
  44
  45 /* Like 'open', but ensures that the returned file descriptor has the
  46    close-on-exec flag set.  */
  47
  48 extern int gdb_open_cloexec (const char *filename, int flags,
  49                              /* mode_t */ unsigned long mode);
  50
  51 /* Convenience wrapper for the above, which takes the filename as an
  52    std::string.  */
  53
  54 static inline int
  55 gdb_open_cloexec (const std::string &filename, int flags,
  56                   /* mode_t */ unsigned long mode)
  57 {
  58   return gdb_open_cloexec (filename.c_str (), flags, mode);
  59 }
  60
  61 struct gdb_file_deleter
  62 {
  63   void operator() (FILE *file) const
  64   {
  65     fclose (file);
  66   }
  67 };
  68
  69 /* A unique pointer to a FILE.  */
  70
  71 typedef std::unique_ptr<FILE, gdb_file_deleter> gdb_file_up;
  72
  73 /* Like 'fopen', but ensures that the returned file descriptor has the
  74    close-on-exec flag set.  */
  75
  76 extern gdb_file_up gdb_fopen_cloexec (const char *filename,
  77                                       const char *opentype);
  78
  79 /* Convenience wrapper for the above, which takes the filename as an
  80    std::string.  */
  81
  82 static inline gdb_file_up
  83 gdb_fopen_cloexec (const std::string &filename, const char *opentype)
  84 {
  85   return gdb_fopen_cloexec (filename.c_str (), opentype);
  86 }
  87
  88 /* Like 'socketpair', but ensures that the returned file descriptors
  89    have the close-on-exec flag set.  */
  90
  91 extern int gdb_socketpair_cloexec (int domain, int style, int protocol,
  92                                    int filedes[2]);
  93
  94 /* Like 'socket', but ensures that the returned file descriptor has
  95    the close-on-exec flag set.  */
  96
  97 extern int gdb_socket_cloexec (int domain, int style, int protocol);
  98
  99 /* Like 'pipe', but ensures that the returned file descriptors have
 100    the close-on-exec flag set.  */
 101
 102 extern int gdb_pipe_cloexec (int filedes[2]);
 103
 104 /* Return a new cleanup that closes FD.  */
 105
 106 extern struct cleanup *make_cleanup_close (int fd);
 107
 108 struct gdb_dir_deleter
 109 {
 110   void operator() (DIR *dir) const
 111   {
 112     closedir (dir);
 113   }
 114 };
 115
 116 /* A unique pointer to a DIR.  */
 117
 118 typedef std::unique_ptr<DIR, gdb_dir_deleter> gdb_dir_up;
 119
 120 /* Return true if the file NAME exists and is a regular file.
 121    If the result is false then *ERRNO_PTR is set to a useful value assuming
 122    we're expecting a regular file.  */
 123 extern bool is_regular_file (const char *name, int *errno_ptr);
 124
 125 #endif /* FILESTUFF_H */