fix live migration

[qemu.git] / iov.h

diff --git a/iov.h b/iov.h
index 9b6a883922f8bba0fc78e7e5f932c6bb56ff3a06..34c8ec9faab0dfa7356a3cf72c962e5a1604db5f 100644 (file)
--- a/iov.h
+++ b/iov.h
@@ -36,7 +36,7 @@ size_t iov_size(const struct iovec *iov, const unsigned int iov_cnt);
  * such "large" value is -1 (sinice size_t is unsigned),
  * so specifying `-1' as `bytes' means 'up to the end of iovec'.
  */
-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 iov_to_buf(const struct iovec *iov, const unsigned int iov_cnt,
                   size_t offset, void *buf, size_t bytes);
@@ -60,7 +60,7 @@ size_t iov_memset(const struct iovec *iov, const unsigned int iov_cnt,
  * `offset' bytes in the beginning of iovec buffer are skipped and
  * next `bytes' bytes are used, which must be within data of iovec.
  *
- *   r = iov_send_recv(sockfd, iov, offset, bytes, true);
+ *   r = iov_send_recv(sockfd, iov, iovcnt, offset, bytes, true);
  *
  * is logically equivalent to
  *
@@ -68,13 +68,16 @@ size_t iov_memset(const struct iovec *iov, const unsigned int iov_cnt,
  *   iov_to_buf(iov, iovcnt, offset, buf, bytes);
  *   r = send(sockfd, buf, bytes, 0);
  *   free(buf);
+ *
+ * For iov_send_recv() _whole_ area being sent or received
+ * should be within the iovec, not only beginning of it.
  */
-ssize_t iov_send_recv(int sockfd, struct iovec *iov,
+ssize_t iov_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt,
                       size_t offset, size_t bytes, bool do_send);
-#define iov_recv(sockfd, iov, offset, bytes) \
-  iov_send_recv(sockfd, iov, offset, bytes, false)
-#define iov_send(sockfd, iov, offset, bytes) \
-  iov_send_recv(sockfd, iov, offset, bytes, true)
+#define iov_recv(sockfd, iov, iov_cnt, offset, bytes) \
+  iov_send_recv(sockfd, iov, iov_cnt, offset, bytes, false)
+#define iov_send(sockfd, iov, iov_cnt, offset, bytes) \
+  iov_send_recv(sockfd, iov, iov_cnt, offset, bytes, true)
 
 /**
  * Produce a text hexdump of iovec `iov' with `iov_cnt' number of elements
@@ -83,3 +86,12 @@ ssize_t iov_send_recv(int sockfd, struct iovec *iov,
  */
 void iov_hexdump(const struct iovec *iov, const unsigned int iov_cnt,
                  FILE *fp, const char *prefix, size_t limit);
+
+/*
+ * Partial copy of vector from iov to dst_iov (data is not copied).
+ * dst_iov overlaps iov at a specified offset.
+ * size of dst_iov is at most bytes. dst vector count is returned.
+ */
+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);