root / iov.c @ 904ebffe
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/*
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* Helpers for getting linearized buffers from iov / filling buffers into iovs
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*
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* Copyright IBM, Corp. 2007, 2008
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* Copyright (C) 2010 Red Hat, Inc.
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*
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* Author(s):
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* Anthony Liguori <aliguori@us.ibm.com>
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* Amit Shah <amit.shah@redhat.com>
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*
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* This work is licensed under the terms of the GNU GPL, version 2. See
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* the COPYING file in the top-level directory.
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*/
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#include "iov.h" |
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size_t iov_from_buf(struct iovec *iov, unsigned int iovcnt, |
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const void *buf, size_t size) |
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{ |
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size_t offset; |
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unsigned int i; |
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offset = 0;
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for (i = 0; offset < size && i < iovcnt; i++) { |
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size_t len; |
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len = MIN(iov[i].iov_len, size - offset); |
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memcpy(iov[i].iov_base, buf + offset, len); |
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offset += len; |
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} |
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return offset;
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} |
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size_t iov_to_buf(const struct iovec *iov, const unsigned int iovcnt, |
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void *buf, size_t offset, size_t size)
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{ |
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uint8_t *ptr; |
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size_t iov_off, buf_off; |
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unsigned int i; |
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ptr = buf; |
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iov_off = 0;
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buf_off = 0;
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for (i = 0; i < iovcnt && size; i++) { |
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if (offset < (iov_off + iov[i].iov_len)) {
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size_t len = MIN((iov_off + iov[i].iov_len) - offset , size); |
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memcpy(ptr + buf_off, iov[i].iov_base + (offset - iov_off), len); |
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buf_off += len; |
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offset += len; |
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size -= len; |
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} |
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iov_off += iov[i].iov_len; |
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} |
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return buf_off;
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} |
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size_t iov_size(const struct iovec *iov, const unsigned int iovcnt) |
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{ |
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size_t len; |
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unsigned int i; |
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len = 0;
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for (i = 0; i < iovcnt; i++) { |
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len += iov[i].iov_len; |
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} |
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return len;
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} |