iov: Improve documentation of iov_skip_bytes()

As pointed out in review, the documentation comments for iov_skip_bytes()
are more confusing than they should be.  Reword them, including updating
parameter names, to make it clearer.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
This commit is contained in:
David Gibson 2024-03-01 15:06:44 +11:00 committed by Stefano Brivio
parent bb11d15495
commit 137ce01789
2 changed files with 15 additions and 15 deletions

28
iov.c
View file

@ -26,31 +26,31 @@
#include "iov.h"
/* iov_skip_bytes() - Skip the first n bytes into an IO vector
/* iov_skip_bytes() - Skip leading bytes of an IO vector
* @iov: IO vector
* @n: Number of entries in @iov
* @vec_offset: Total byte offset into the IO vector
* @buf_offset: Offset into a single buffer of the IO vector
* @skip: Number of leading bytes of @iov to skip
* @offset: Offset of first unskipped byte in its @iov entry
*
* Return: index I of individual struct iovec which contains the byte at
* @vec_offset bytes into the vector (as though all its buffers were
* contiguous). If @buf_offset is non-NULL, update it to the offset of
* that byte within @iov[I] (guaranteed to be less than @iov[I].iov_len)
* If the whole vector has <= @vec_offset bytes, return @n.
* Return: index I of individual struct iovec which contains the byte at @skip
* bytes into the vector (as though all its buffers were contiguous).
* If @offset is non-NULL, update it to the offset of that byte within
* @iov[I] (guaranteed to be less than @iov[I].iov_len) If the whole
* vector has <= @skip bytes, return @n.
*/
size_t iov_skip_bytes(const struct iovec *iov, size_t n,
size_t vec_offset, size_t *buf_offset)
size_t skip, size_t *offset)
{
size_t offset = vec_offset, i;
size_t off = skip, i;
for (i = 0; i < n; i++) {
if (offset < iov[i].iov_len)
if (off < iov[i].iov_len)
break;
offset -= iov[i].iov_len;
off -= iov[i].iov_len;
}
if (buf_offset)
*buf_offset = offset;
if (offset)
*offset = off;
return i;
}

2
iov.h
View file

@ -19,7 +19,7 @@
#include <string.h>
size_t iov_skip_bytes(const struct iovec *iov, size_t n,
size_t vec_offset, size_t *buf_offset);
size_t skip, size_t *offset);
size_t iov_from_buf(const struct iovec *iov, size_t iov_cnt,
size_t offset, const void *buf, size_t bytes);
size_t iov_to_buf(const struct iovec *iov, size_t iov_cnt,