1 /* Create a device inode. 2 Copyright (C) 2009-2021 Free Software Foundation, Inc. 3 4 This file is free software: you can redistribute it and/or modify 5 it under the terms of the GNU Lesser General Public License as 6 published by the Free Software Foundation; either version 3 of the 7 License, or (at your option) any later version. 8 9 This file is distributed in the hope that it will be useful, 10 but WITHOUT ANY WARRANTY; without even the implied warranty of 11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 GNU Lesser General Public License for more details. 13 14 You should have received a copy of the GNU Lesser General Public License 15 along with this program. If not, see <https://www.gnu.org/licenses/>. */ 16 17 /* written by Eric Blake */ 18 19 #include <config.h> 20 21 #include <sys/stat.h> 22 23 #include <errno.h> 24 #include <string.h> 25 26 #if !HAVE_MKNOD 27 /* Mingw lacks mknod; always fail with ENOSYS. */ 28 29 int 30 mknod (_GL_UNUSED char const *name, _GL_UNUSED mode_t mode, /* */ 31 _GL_UNUSED dev_t dev) 32 { 33 errno = ENOSYS; 34 return -1; 35 } 36 37 #else /* HAVE_MKNOD */ 38 39 # undef mknod 40 41 /* Create a file system node FILE, with access permissions and file 42 type in MODE, and device type in DEV. Usually, non-root 43 applications can only create named fifos (mode includes S_IFIFO), 44 with DEV set to 0. Also work around trailing slash bugs. */ 45 46 int 47 rpl_mknod (char const *name, mode_t mode, dev_t dev) /* */ 48 { 49 # if MKFIFO_TRAILING_SLASH_BUG 50 /* Trailing slash only makes sense for directories. Of course, 51 using mknod to create a directory is not very portable, so it may 52 still fail later on. */ 53 if (!S_ISDIR (mode)) 54 { 55 size_t len = strlen (name); 56 if (len && name[len - 1] == '/') 57 { 58 struct stat st; 59 if (stat (name, &st) == 0 || errno == EOVERFLOW) 60 errno = EEXIST; 61 return -1; 62 } 63 } 64 # endif 65 # if MKNOD_FIFO_BUG 66 /* POSIX requires mknod to create fifos for non-privileged 67 processes, but BSD implementations fail with EPERM. */ 68 if (S_ISFIFO (mode) && dev == 0) 69 return mkfifo (name, mode & ~S_IFIFO); 70 # endif 71 return mknod (name, mode, dev); 72 } 73 74 #endif /* HAVE_MKNOD */