diff options
Diffstat (limited to 'io/copy_file_range-compat.c')
| -rw-r--r-- | io/copy_file_range-compat.c | 160 |
1 files changed, 0 insertions, 160 deletions
diff --git a/io/copy_file_range-compat.c b/io/copy_file_range-compat.c deleted file mode 100644 index 58dbeef3e9..0000000000 --- a/io/copy_file_range-compat.c +++ /dev/null @@ -1,160 +0,0 @@ -/* Emulation of copy_file_range. - Copyright (C) 2017-2019 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 - <http://www.gnu.org/licenses/>. */ - -/* The following macros should be defined before including this - file: - - COPY_FILE_RANGE_DECL Declaration specifiers for the function below. - COPY_FILE_RANGE Name of the function to define. */ - -#include <errno.h> -#include <fcntl.h> -#include <inttypes.h> -#include <limits.h> -#include <sys/stat.h> -#include <sys/types.h> -#include <unistd.h> - -COPY_FILE_RANGE_DECL -ssize_t -COPY_FILE_RANGE (int infd, __off64_t *pinoff, - int outfd, __off64_t *poutoff, - size_t length, unsigned int flags) -{ - if (flags != 0) - { - __set_errno (EINVAL); - return -1; - } - - { - struct stat64 instat; - struct stat64 outstat; - if (fstat64 (infd, &instat) != 0 || fstat64 (outfd, &outstat) != 0) - return -1; - if (S_ISDIR (instat.st_mode) || S_ISDIR (outstat.st_mode)) - { - __set_errno (EISDIR); - return -1; - } - if (!S_ISREG (instat.st_mode) || !S_ISREG (outstat.st_mode)) - { - /* We need a regular input file so that the we can seek - backwards in case of a write failure. */ - __set_errno (EINVAL); - return -1; - } - if (instat.st_dev != outstat.st_dev) - { - /* Cross-device copies are not supported. */ - __set_errno (EXDEV); - return -1; - } - } - - /* The output descriptor must not have O_APPEND set. */ - { - int flags = __fcntl (outfd, F_GETFL); - if (flags & O_APPEND) - { - __set_errno (EBADF); - return -1; - } - } - - /* Avoid an overflow in the result. */ - if (length > SSIZE_MAX) - length = SSIZE_MAX; - - /* Main copying loop. The buffer size is arbitrary and is a - trade-off between stack size consumption, cache usage, and - amortization of system call overhead. */ - size_t copied = 0; - char buf[8192]; - while (length > 0) - { - size_t to_read = length; - if (to_read > sizeof (buf)) - to_read = sizeof (buf); - - /* Fill the buffer. */ - ssize_t read_count; - if (pinoff == NULL) - read_count = read (infd, buf, to_read); - else - read_count = __libc_pread64 (infd, buf, to_read, *pinoff); - if (read_count == 0) - /* End of file reached prematurely. */ - return copied; - if (read_count < 0) - { - if (copied > 0) - /* Report the number of bytes copied so far. */ - return copied; - return -1; - } - if (pinoff != NULL) - *pinoff += read_count; - - /* Write the buffer part which was read to the destination. */ - char *end = buf + read_count; - for (char *p = buf; p < end; ) - { - ssize_t write_count; - if (poutoff == NULL) - write_count = write (outfd, p, end - p); - else - write_count = __libc_pwrite64 (outfd, p, end - p, *poutoff); - if (write_count < 0) - { - /* Adjust the input read position to match what we have - written, so that the caller can pick up after the - error. */ - size_t written = p - buf; - /* NB: This needs to be signed so that we can form the - negative value below. */ - ssize_t overread = read_count - written; - if (pinoff == NULL) - { - if (overread > 0) - { - /* We are on an error recovery path, so we - cannot deal with failure here. */ - int save_errno = errno; - (void) __libc_lseek64 (infd, -overread, SEEK_CUR); - __set_errno (save_errno); - } - } - else /* pinoff != NULL */ - *pinoff -= overread; - - if (copied + written > 0) - /* Report the number of bytes copied so far. */ - return copied + written; - return -1; - } - p += write_count; - if (poutoff != NULL) - *poutoff += write_count; - } /* Write loop. */ - - copied += read_count; - length -= read_count; - } - return copied; -} |