sockets.c: Use size_t for iovec length

This change updates the lwip socket read/write ops to use unsigned
size_t for the length of the passed-in iovec.

The internal lwip read/write functions still use int, and simply package
it into struct msghdr, which is size_t once again.
If overflow is a concern we should fix it with a build patch.

Signed-off-by: Andrei Tatar <[email protected]>
Reviewed-by: Sergiu Moga <[email protected]>
Approved-by: Razvan Deaconescu <[email protected]>
GitHub-Closes: #61

Author: andreittr

sockets.c

@@ -343,7 +343,7 @@ lwip_posix_socket_sendto(posix_sock *file, const void *buf,
 
 static ssize_t
 lwip_posix_socket_read(posix_sock *file, const struct iovec *iov,
-		       int iovcnt)
+		       size_t iovcnt)
 {
 	int lwip_fd;
 	ssize_t ret;
@@ -360,7 +360,7 @@ lwip_posix_socket_read(posix_sock *file, const struct iovec *iov,
 
 static ssize_t
 lwip_posix_socket_write(posix_sock *file, const struct iovec *iov,
-		       int iovcnt)
+			size_t iovcnt)
 {
 	int lwip_fd;
 	ssize_t ret;