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-rw-r--r--sysdeps/posix/preadv_common.c83
1 files changed, 0 insertions, 83 deletions
diff --git a/sysdeps/posix/preadv_common.c b/sysdeps/posix/preadv_common.c
deleted file mode 100644
index 37efdc0ec0..0000000000
--- a/sysdeps/posix/preadv_common.c
+++ /dev/null
@@ -1,83 +0,0 @@
-/* Read data into multiple buffers. Base implementation for preadv
- and preadv64.
- 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
- <http://www.gnu.org/licenses/>. */
-
-#include <unistd.h>
-#include <sys/uio.h>
-#include <sys/param.h>
-#include <errno.h>
-#include <malloc.h>
-
-#include <ldsodefs.h>
-
-/* Read data from file descriptor FD at the given position OFFSET
- without change the file pointer, and put the result in the buffers
- described by VECTOR, which is a vector of COUNT 'struct iovec's.
- The buffers are filled in the order specified. Operates just like
- 'pread' (see <unistd.h>) except that data are put in VECTOR instead
- of a contiguous buffer. */
-ssize_t
-PREADV (int fd, const struct iovec *vector, int count, OFF_T offset)
-{
- /* Find the total number of bytes to be read. */
- size_t bytes = 0;
- for (int i = 0; i < count; ++i)
- {
- /* Check for ssize_t overflow. */
- if (SSIZE_MAX - bytes < vector[i].iov_len)
- {
- __set_errno (EINVAL);
- return -1;
- }
- bytes += vector[i].iov_len;
- }
-
- /* Allocate a temporary buffer to hold the data. It could be done with a
- stack allocation, but due limitations on some system (Linux with
- O_DIRECT) it aligns the buffer to pagesize. A possible optimization
- would be querying if the syscall would impose any alignment constraint,
- but 1. it is system specific (not meant in generic implementation), and
- 2. it would make the implementation more complex, and 3. it will require
- another syscall (fcntl). */
- void *buffer = NULL;
- if (__posix_memalign (&buffer, GLRO(dl_pagesize), bytes) != 0)
- return -1;
-
- ssize_t bytes_read = PREAD (fd, buffer, bytes, offset);
- if (bytes_read < 0)
- goto end;
-
- /* Copy the data from BUFFER into the memory specified by VECTOR. */
- bytes = bytes_read;
- void *buf = buffer;
- for (int i = 0; i < count; ++i)
- {
- size_t copy = MIN (vector[i].iov_len, bytes);
-
- memcpy (vector[i].iov_base, buf, copy);
-
- buf += copy;
- bytes -= copy;
- if (bytes == 0)
- break;
- }
-
-end:
- free (buffer);
- return bytes_read;
-}