From bad7a0c81f501fbbcc79af9eaa4b8254441c4a1f Mon Sep 17 00:00:00 2001 From: Florian Weimer Date: Fri, 22 Dec 2017 10:55:40 +0100 Subject: copy_file_range: New function to copy file data The semantics are based on the Linux system call, but a very close emulation in user space is provided. --- sysdeps/unix/sysv/linux/copy_file_range.c | 46 +++++++++++++++++++++++++++++++ 1 file changed, 46 insertions(+) create mode 100644 sysdeps/unix/sysv/linux/copy_file_range.c (limited to 'sysdeps/unix/sysv/linux/copy_file_range.c') diff --git a/sysdeps/unix/sysv/linux/copy_file_range.c b/sysdeps/unix/sysv/linux/copy_file_range.c new file mode 100644 index 0000000..1ec5f9d --- /dev/null +++ b/sysdeps/unix/sysv/linux/copy_file_range.c @@ -0,0 +1,46 @@ +/* Linux implementation of copy_file_range. + Copyright (C) 2017 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 Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 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 + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#include +#include +#include + +/* Include the fallback implementation. */ +#ifndef __ASSUME_COPY_FILE_RANGE +#define COPY_FILE_RANGE_DECL static +#define COPY_FILE_RANGE copy_file_range_compat +#include +#endif + +ssize_t +copy_file_range (int infd, __off64_t *pinoff, + int outfd, __off64_t *poutoff, + size_t length, unsigned int flags) +{ +#ifdef __NR_copy_file_range + ssize_t ret = SYSCALL_CANCEL (copy_file_range, infd, pinoff, outfd, poutoff, + length, flags); +# ifndef __ASSUME_COPY_FILE_RANGE + if (ret == -1 && errno == ENOSYS) + ret = copy_file_range_compat (infd, pinoff, outfd, poutoff, length, flags); +# endif + return ret; +#else /* !__NR_copy_file_range */ + return copy_file_range_compat (infd, pinoff, outfd, poutoff, length, flags); +#endif +} -- cgit v1.1