# include <sys/socket.h>
#endif
-size_t iov_from_buf(struct iovec *iov, unsigned int iov_cnt,
+size_t iov_from_buf(const struct iovec *iov, unsigned int iov_cnt,
size_t offset, const void *buf, size_t bytes)
{
size_t done;
{
ssize_t ret;
unsigned si, ei; /* start and end indexes */
+ if (bytes == 0) {
+ /* Catch the do-nothing case early, as otherwise we will pass an
+ * empty iovec to sendmsg/recvmsg(), and not all implementations
+ * accept this.
+ */
+ return 0;
+ }
/* Find the start position, skipping `offset' bytes:
* first, skip all full-sized vector elements, */
fprintf(fp, "\n");
}
}
+
+unsigned iov_copy(struct iovec *dst_iov, unsigned int dst_iov_cnt,
+ const struct iovec *iov, unsigned int iov_cnt,
+ size_t offset, size_t bytes)
+{
+ size_t len;
+ unsigned int i, j;
+ for (i = 0, j = 0; i < iov_cnt && j < dst_iov_cnt && bytes; i++) {
+ if (offset >= iov[i].iov_len) {
+ offset -= iov[i].iov_len;
+ continue;
+ }
+ len = MIN(bytes, iov[i].iov_len - offset);
+
+ dst_iov[j].iov_base = iov[i].iov_base + offset;
+ dst_iov[j].iov_len = len;
+ j++;
+ bytes -= len;
+ offset = 0;
+ }
+ assert(offset == 0);
+ return j;
+}