1/* Low-level file-handling.
2   Copyright (C) 2012-2023 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 COMMON_FILESTUFF_H
20#define COMMON_FILESTUFF_H
21
22#include <dirent.h>
23#include <fcntl.h>
24#include "gdb_file.h"
25#include "scoped_fd.h"
26
27/* Note all the file descriptors which are open when this is called.
28   These file descriptors will not be closed by close_most_fds.  */
29
30extern void notice_open_fds (void);
31
32/* Mark a file descriptor as inheritable across an exec.  */
33
34extern void mark_fd_no_cloexec (int fd);
35
36/* Mark a file descriptor as no longer being inheritable across an
37   exec.  This is only meaningful when FD was previously passed to
38   mark_fd_no_cloexec.  */
39
40extern void unmark_fd_no_cloexec (int fd);
41
42/* Close all open file descriptors other than those marked by
43   'notice_open_fds', and stdin, stdout, and stderr.  Errors that
44   occur while closing are ignored.  */
45
46extern void close_most_fds (void);
47
48/* Like 'open', but ensures that the returned file descriptor has the
49   close-on-exec flag set.  */
50
51extern scoped_fd gdb_open_cloexec (const char *filename, int flags,
52				   /* mode_t */ unsigned long mode);
53
54/* Like mkstemp, but ensures that the file descriptor is
55   close-on-exec.  */
56
57static inline scoped_fd
58gdb_mkostemp_cloexec (char *name_template, int flags = 0)
59{
60  /* gnulib provides a mkostemp replacement if needed.  */
61  return scoped_fd (mkostemp (name_template, flags | O_CLOEXEC));
62}
63
64/* Convenience wrapper for the above, which takes the filename as an
65   std::string.  */
66
67static inline scoped_fd
68gdb_open_cloexec (const std::string &filename, int flags,
69		  /* mode_t */ unsigned long mode)
70{
71  return gdb_open_cloexec (filename.c_str (), flags, mode);
72}
73
74/* Like 'fopen', but ensures that the returned file descriptor has the
75   close-on-exec flag set.  */
76
77extern gdb_file_up gdb_fopen_cloexec (const char *filename,
78				      const char *opentype);
79
80/* Convenience wrapper for the above, which takes the filename as an
81   std::string.  */
82
83static inline gdb_file_up
84gdb_fopen_cloexec (const std::string &filename, const char *opentype)
85{
86  return gdb_fopen_cloexec (filename.c_str (), opentype);
87}
88
89/* Like 'socketpair', but ensures that the returned file descriptors
90   have the close-on-exec flag set.  */
91
92extern int gdb_socketpair_cloexec (int domain, int style, int protocol,
93				   int filedes[2]);
94
95/* Like 'socket', but ensures that the returned file descriptor has
96   the close-on-exec flag set.  */
97
98extern int gdb_socket_cloexec (int domain, int style, int protocol);
99
100/* Like 'pipe', but ensures that the returned file descriptors have
101   the close-on-exec flag set.  */
102
103extern int gdb_pipe_cloexec (int filedes[2]);
104
105struct gdb_dir_deleter
106{
107  void operator() (DIR *dir) const
108  {
109    closedir (dir);
110  }
111};
112
113/* A unique pointer to a DIR.  */
114
115typedef std::unique_ptr<DIR, gdb_dir_deleter> gdb_dir_up;
116
117/* Return true if the file NAME exists and is a regular file.
118   If the result is false then *ERRNO_PTR is set to a useful value assuming
119   we're expecting a regular file.  */
120extern bool is_regular_file (const char *name, int *errno_ptr);
121
122
123/* A cheap (as in low-quality) recursive mkdir.  Try to create all the
124   parents directories up to DIR and DIR itself.  Stop if we hit an
125   error along the way.  There is no attempt to remove created
126   directories in case of failure.
127
128   Returns false on failure and sets errno.  */
129
130extern bool mkdir_recursive (const char *dir);
131
132/* Read the entire content of file PATH into an std::string.  */
133
134extern gdb::optional<std::string> read_text_file_to_string (const char *path);
135
136#endif /* COMMON_FILESTUFF_H */
137