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