risu: parameterise send/receive functions

This is a precursor to record/playback support. Instead of passing the
socket fd we now pass helper functions for reading/writing and
responding. This will allow us to do the rest of the record/playback
cleanly outside of the main worker function.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 20170621154244.28309-5-alex.bennee@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
[PMM: fixed checkpatch nits]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 13 insertions, 2 deletions

diff --git a/risu.h b/risu.h
index 70c2184..8eb6227 100644
--- a/risu.h
+++ b/risu.h
@@ -57,17 +57,28 @@ struct reginfo;
 
 /* Functions operating on reginfo */
 
+/* Function prototypes for read/write helper functions.
+ *
+ * We pass the helper function to send_register_info and
+ * recv_and_compare_register_info which can either be backed by the
+ * traditional network socket or a trace file.
+ */
+typedef int (*write_fn) (void *ptr, size_t bytes);
+typedef int (*read_fn) (void *ptr, size_t bytes);
+typedef void (*respond_fn) (int response);
+
 /* Send the register information from the struct ucontext down the socket.
  * Return the response code from the master.
  * NB: called from a signal handler.
  */
-int send_register_info(int sock, void *uc);
+int send_register_info(write_fn write_fn, void *uc);
 
 /* Read register info from the socket and compare it with that from the
  * ucontext. Return 0 for match, 1 for end-of-test, 2 for mismatch.
  * NB: called from a signal handler.
  */
-int recv_and_compare_register_info(int sock, void *uc);
+int recv_and_compare_register_info(read_fn read_fn,
+                                   respond_fn respond, void *uc);
 
 /* Print a useful report on the status of the last comparison
  * done in recv_and_compare_register_info(). This is called on