diff options
Diffstat (limited to 'sysdeps/posix/posix_fallocate64.c')
-rw-r--r-- | sysdeps/posix/posix_fallocate64.c | 71 |
1 files changed, 71 insertions, 0 deletions
diff --git a/sysdeps/posix/posix_fallocate64.c b/sysdeps/posix/posix_fallocate64.c new file mode 100644 index 0000000000..539244de58 --- /dev/null +++ b/sysdeps/posix/posix_fallocate64.c @@ -0,0 +1,71 @@ +/* Copyright (C) 2000 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Library General Public License as + published by the Free Software Foundation; either version 2 of the + License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Library General Public License for more details. + + You should have received a copy of the GNU Library General Public + License along with the GNU C Library; see the file COPYING.LIB. If not, + write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, + Boston, MA 02111-1307, USA. */ + +#include <errno.h> +#include <fcntl.h> +#include <unistd.h> +#include <sys/stat.h> +#include <sys/statfs.h> + +/* Reserve storage for the data of the file associated with FD. */ + +int +posix_fallocate64 (int fd, __off64_t offset, size_t len) +{ + struct stat64 st; + struct statfs64 f; + size_t step; + + /* `off64_tī is a signed type. Therefore we can determine whether + OFFSET + LEN is too large if it is a negative value. */ + if (offset < 0 || len == 0) + return EINVAL; + if (offset + len < 0) + return EFBIG; + + /* First thing we have to make sure is that this is really a regular + file. */ + if (__fxstat64 (_STAT_VER, fd, &st) != 0) + return EBADF; + if (S_ISFIFO (st.st_mode)) + return ESPIPE; + if (! S_ISREG (st.st_mode)) + return ENODEV; + + /* We have to know the block size of the filesystem to get at least some + sort of performance. */ + if (__fstatfs64 (fd, &f) != 0) + return errno; + + /* Align OFFSET to block size and adjust LEN. */ + step = (offset + f.f_bsize - 1) % ~f.f_bsize; + offset += step; + + /* Write something to every block. */ + while (len > step) + { + len -= step; + + if (pwrite64 (fd, "", 1, offset) != 1) + return errno; + + offset += step; + } + + return 0; +} |