130 lines
		
	
	
		
			3.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			130 lines
		
	
	
		
			3.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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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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| 
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| #include "iov.h"
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| 
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| size_t iov_from_buf(struct iovec *iov, unsigned int iov_cnt,
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|                     const void *buf, size_t iov_off, size_t size)
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| {
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|     size_t iovec_off, buf_off;
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|     unsigned int i;
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| 
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|     iovec_off = 0;
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|     buf_off = 0;
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|     for (i = 0; i < iov_cnt && size; i++) {
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|         if (iov_off < (iovec_off + iov[i].iov_len)) {
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|             size_t len = MIN((iovec_off + iov[i].iov_len) - iov_off, size);
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| 
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|             memcpy(iov[i].iov_base + (iov_off - iovec_off), buf + buf_off, len);
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| 
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|             buf_off += len;
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|             iov_off += len;
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|             size -= len;
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|         }
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|         iovec_off += iov[i].iov_len;
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|     }
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|     return buf_off;
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| }
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| 
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| size_t iov_to_buf(const struct iovec *iov, const unsigned int iov_cnt,
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|                   void *buf, size_t iov_off, size_t size)
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| {
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|     uint8_t *ptr;
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|     size_t iovec_off, buf_off;
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|     unsigned int i;
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| 
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|     ptr = buf;
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|     iovec_off = 0;
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|     buf_off = 0;
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|     for (i = 0; i < iov_cnt && size; i++) {
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|         if (iov_off < (iovec_off + iov[i].iov_len)) {
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|             size_t len = MIN((iovec_off + iov[i].iov_len) - iov_off , size);
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| 
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|             memcpy(ptr + buf_off, iov[i].iov_base + (iov_off - iovec_off), len);
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| 
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|             buf_off += len;
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|             iov_off += len;
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|             size -= len;
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|         }
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|         iovec_off += iov[i].iov_len;
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|     }
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|     return buf_off;
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| }
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| 
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| size_t iov_clear(const struct iovec *iov, const unsigned int iov_cnt,
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|                  size_t iov_off, size_t size)
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| {
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|     size_t iovec_off, buf_off;
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|     unsigned int i;
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| 
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|     iovec_off = 0;
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|     buf_off = 0;
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|     for (i = 0; i < iov_cnt && size; i++) {
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|         if (iov_off < (iovec_off + iov[i].iov_len)) {
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|             size_t len = MIN((iovec_off + iov[i].iov_len) - iov_off , size);
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| 
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|             memset(iov[i].iov_base + (iov_off - iovec_off), 0, len);
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| 
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|             buf_off += len;
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|             iov_off += len;
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|             size -= len;
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|         }
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|         iovec_off += iov[i].iov_len;
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|     }
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|     return buf_off;
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| }
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| 
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| size_t iov_size(const struct iovec *iov, const unsigned int iov_cnt)
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| {
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|     size_t len;
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|     unsigned int i;
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| 
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|     len = 0;
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|     for (i = 0; i < iov_cnt; i++) {
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|         len += iov[i].iov_len;
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|     }
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|     return len;
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| }
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| 
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| void iov_hexdump(const struct iovec *iov, const unsigned int iov_cnt,
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|                  FILE *fp, const char *prefix, size_t limit)
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| {
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|     unsigned int i, v, b;
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|     uint8_t *c;
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| 
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|     c = iov[0].iov_base;
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|     for (i = 0, v = 0, b = 0; b < limit; i++, b++) {
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|         if (i == iov[v].iov_len) {
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|             i = 0; v++;
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|             if (v == iov_cnt) {
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|                 break;
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|             }
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|             c = iov[v].iov_base;
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|         }
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|         if ((b % 16) == 0) {
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|             fprintf(fp, "%s: %04x:", prefix, b);
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|         }
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|         if ((b % 4) == 0) {
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|             fprintf(fp, " ");
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|         }
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|         fprintf(fp, " %02x", c[i]);
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|         if ((b % 16) == 15) {
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|             fprintf(fp, "\n");
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|         }
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|     }
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|     if ((b % 16) != 0) {
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|         fprintf(fp, "\n");
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|     }
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| }
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