| 1 | /* Low-level file-handling. |
| 2 | Copyright (C) 2012-2020 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 | |
| 25 | /* Note all the file descriptors which are open when this is called. |
| 26 | These file descriptors will not be closed by close_most_fds. */ |
| 27 | |
| 28 | extern void notice_open_fds (void); |
| 29 | |
| 30 | /* Mark a file descriptor as inheritable across an exec. */ |
| 31 | |
| 32 | extern void mark_fd_no_cloexec (int fd); |
| 33 | |
| 34 | /* Mark a file descriptor as no longer being inheritable across an |
| 35 | exec. This is only meaningful when FD was previously passed to |
| 36 | mark_fd_no_cloexec. */ |
| 37 | |
| 38 | extern void unmark_fd_no_cloexec (int fd); |
| 39 | |
| 40 | /* Close all open file descriptors other than those marked by |
| 41 | 'notice_open_fds', and stdin, stdout, and stderr. Errors that |
| 42 | occur while closing are ignored. */ |
| 43 | |
| 44 | extern void close_most_fds (void); |
| 45 | |
| 46 | /* Like 'open', but ensures that the returned file descriptor has the |
| 47 | close-on-exec flag set. */ |
| 48 | |
| 49 | extern int gdb_open_cloexec (const char *filename, int flags, |
| 50 | /* mode_t */ unsigned long mode); |
| 51 | |
| 52 | /* Like mkstemp, but ensures that the file descriptor is |
| 53 | close-on-exec. */ |
| 54 | |
| 55 | static inline int |
| 56 | gdb_mkostemp_cloexec (char *name_template, int flags = 0) |
| 57 | { |
| 58 | /* gnulib provides a mkostemp replacement if needed. */ |
| 59 | return mkostemp (name_template, flags | O_CLOEXEC); |
| 60 | } |
| 61 | |
| 62 | /* Convenience wrapper for the above, which takes the filename as an |
| 63 | std::string. */ |
| 64 | |
| 65 | static inline int |
| 66 | gdb_open_cloexec (const std::string &filename, int flags, |
| 67 | /* mode_t */ unsigned long mode) |
| 68 | { |
| 69 | return gdb_open_cloexec (filename.c_str (), flags, mode); |
| 70 | } |
| 71 | |
| 72 | struct gdb_file_deleter |
| 73 | { |
| 74 | void operator() (FILE *file) const |
| 75 | { |
| 76 | fclose (file); |
| 77 | } |
| 78 | }; |
| 79 | |
| 80 | /* A unique pointer to a FILE. */ |
| 81 | |
| 82 | typedef std::unique_ptr<FILE, gdb_file_deleter> gdb_file_up; |
| 83 | |
| 84 | /* Like 'fopen', but ensures that the returned file descriptor has the |
| 85 | close-on-exec flag set. */ |
| 86 | |
| 87 | extern gdb_file_up gdb_fopen_cloexec (const char *filename, |
| 88 | const char *opentype); |
| 89 | |
| 90 | /* Convenience wrapper for the above, which takes the filename as an |
| 91 | std::string. */ |
| 92 | |
| 93 | static inline gdb_file_up |
| 94 | gdb_fopen_cloexec (const std::string &filename, const char *opentype) |
| 95 | { |
| 96 | return gdb_fopen_cloexec (filename.c_str (), opentype); |
| 97 | } |
| 98 | |
| 99 | /* Like 'socketpair', but ensures that the returned file descriptors |
| 100 | have the close-on-exec flag set. */ |
| 101 | |
| 102 | extern int gdb_socketpair_cloexec (int domain, int style, int protocol, |
| 103 | int filedes[2]); |
| 104 | |
| 105 | /* Like 'socket', but ensures that the returned file descriptor has |
| 106 | the close-on-exec flag set. */ |
| 107 | |
| 108 | extern int gdb_socket_cloexec (int domain, int style, int protocol); |
| 109 | |
| 110 | /* Like 'pipe', but ensures that the returned file descriptors have |
| 111 | the close-on-exec flag set. */ |
| 112 | |
| 113 | extern int gdb_pipe_cloexec (int filedes[2]); |
| 114 | |
| 115 | struct gdb_dir_deleter |
| 116 | { |
| 117 | void operator() (DIR *dir) const |
| 118 | { |
| 119 | closedir (dir); |
| 120 | } |
| 121 | }; |
| 122 | |
| 123 | /* A unique pointer to a DIR. */ |
| 124 | |
| 125 | typedef std::unique_ptr<DIR, gdb_dir_deleter> gdb_dir_up; |
| 126 | |
| 127 | /* Return true if the file NAME exists and is a regular file. |
| 128 | If the result is false then *ERRNO_PTR is set to a useful value assuming |
| 129 | we're expecting a regular file. */ |
| 130 | extern bool is_regular_file (const char *name, int *errno_ptr); |
| 131 | |
| 132 | |
| 133 | /* A cheap (as in low-quality) recursive mkdir. Try to create all the |
| 134 | parents directories up to DIR and DIR itself. Stop if we hit an |
| 135 | error along the way. There is no attempt to remove created |
| 136 | directories in case of failure. |
| 137 | |
| 138 | Returns false on failure and sets errno. */ |
| 139 | |
| 140 | extern bool mkdir_recursive (const char *dir); |
| 141 | |
| 142 | #endif /* COMMON_FILESTUFF_H */ |