diff options
Diffstat (limited to 'iov.c')
| -rw-r--r-- | iov.c | 53 |
1 files changed, 44 insertions, 9 deletions
@@ -109,7 +109,7 @@ size_t iov_from_buf(const struct iovec *iov, size_t iov_cnt, * * Return: the number of bytes successfully copied. */ -/* cppcheck-suppress unusedFunction */ +/* cppcheck-suppress [staticFunction] */ size_t iov_to_buf(const struct iovec *iov, size_t iov_cnt, size_t offset, void *buf, size_t bytes) { @@ -127,6 +127,7 @@ size_t iov_to_buf(const struct iovec *iov, size_t iov_cnt, /* copying data */ for (copied = 0; copied < bytes && i < iov_cnt; i++) { size_t len = MIN(iov[i].iov_len - offset, bytes - copied); + ASSERT(iov[i].iov_base); memcpy((char *)buf + copied, (char *)iov[i].iov_base + offset, len); copied += len; @@ -208,7 +209,7 @@ bool iov_drop_header(struct iov_tail *tail, size_t len) } /** - * iov_peek_header_() - Get pointer to a header from an IOV tail + * iov_check_header() - Check if a header can be accessed * @tail: IOV tail to get header from * @len: Length of header to get, in bytes * @align: Required alignment of header, in bytes @@ -219,8 +220,7 @@ bool iov_drop_header(struct iov_tail *tail, size_t len) * overruns the IO vector, is not contiguous or doesn't have the * requested alignment. */ -/* cppcheck-suppress [staticFunction,unmatchedSuppression] */ -void *iov_peek_header_(struct iov_tail *tail, size_t len, size_t align) +static void *iov_check_header(struct iov_tail *tail, size_t len, size_t align) { char *p; @@ -241,26 +241,61 @@ void *iov_peek_header_(struct iov_tail *tail, size_t len, size_t align) } /** + * iov_peek_header_() - Get pointer to a header from an IOV tail + * @tail: IOV tail to get header from + * @v: Temporary memory to use if the memory in @tail + * is discontinuous + * @len: Length of header to get, in bytes + * @align: Required alignment of header, in bytes + * + * @tail may be pruned, but will represent the same bytes as before. + * + * Return: pointer to the first @len logical bytes of the tail, or to + * a copy if that overruns the IO vector, is not contiguous or + * doesn't have the requested alignment. NULL if that overruns the + * IO vector. + */ +/* cppcheck-suppress [staticFunction,unmatchedSuppression] */ +void *iov_peek_header_(struct iov_tail *tail, void *v, size_t len, size_t align) +{ + char *p = iov_check_header(tail, len, align); + size_t l; + + if (p) + return p; + + l = iov_to_buf(tail->iov, tail->cnt, tail->off, v, len); + if (l != len) + return NULL; + + return v; +} + +/** * iov_remove_header_() - Remove a header from an IOV tail * @tail: IOV tail to remove header from (modified) + * @v: Temporary memory to use if the memory in @tail + * is discontinuous * @len: Length of header to remove, in bytes * @align: Required alignment of header, in bytes * * On success, @tail is updated so that it longer includes the bytes of the * returned header. * - * Return: pointer to the first @len logical bytes of the tail, NULL if that - * overruns the IO vector, is not contiguous or doesn't have the - * requested alignment. + * Return: pointer to the first @len logical bytes of the tail, or to + * a copy if that overruns the IO vector, is not contiguous or + * doesn't have the requested alignment. NULL if that overruns the + * IO vector. */ -void *iov_remove_header_(struct iov_tail *tail, size_t len, size_t align) +void *iov_remove_header_(struct iov_tail *tail, void *v, size_t len, size_t align) { - char *p = iov_peek_header_(tail, len, align); + char *p = iov_peek_header_(tail, v, len, align); if (!p) return NULL; tail->off = tail->off + len; + return p; } |