>From 0c4ffccc7258dcff94cc40abcf470a3c5ad788c3 Mon Sep 17 00:00:00 2001
From: "Richard W.M. Jones" <rjones@redhat.com>
Date: Tue, 14 Oct 2014 14:31:08 +0200
Subject: [PATCH 2/2] tests: Enable streaming test.

---
 plugins/streaming/streaming.c | 13 +++++++++++--
 tests/Makefile.am             | 17 +++++------------
 tests/test-streaming.c        | 16 +++++++---------
 3 files changed, 23 insertions(+), 23 deletions(-)

diff --git a/plugins/streaming/streaming.c b/plugins/streaming/streaming.c
index 2d08803..da4de63 100644
--- a/plugins/streaming/streaming.c
+++ b/plugins/streaming/streaming.c
@@ -35,6 +35,8 @@
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <stdint.h>
+#include <inttypes.h>
 #include <string.h>
 #include <fcntl.h>
 #include <unistd.h>
@@ -232,6 +234,10 @@ streaming_pwrite (void *handle, const void *buf,
     return -1;
   }
 
+  nbdkit_debug ("pwrite: offset=%" PRIi64 " count=%" PRIu32
+                " highestwrite=%" PRIu64,
+                offset, count, highestwrite);
+
   /* This just makes the recursive case easier to reason about. */
   if (count == 0)
     return 0;
@@ -239,7 +245,8 @@ streaming_pwrite (void *handle, const void *buf,
   windowstart = highestwrite - window_size;
 
   if (offset < windowstart) {
-    nbdkit_error ("client seeked backwards > window size: you must increase the window size");
+    nbdkit_error ("pwrite: client backwards seek > window size: you must increase the window size (highestwrite=%" PRIu64 ", window_size=%" PRIi64 ")",
+                  highestwrite, window_size);
     errorstate = 1;
     errno = EIO;
     return -1;
@@ -298,6 +305,7 @@ streaming_pwrite (void *handle, const void *buf,
     window = new_window;
     /* Make sure the extended window is zeroes to start with. */
     memset (&window[window_size], 0, new_size - window_size);
+    window_size = new_size;
     highestwrite = new_highestwrite;
     /* Copy the buffer to the new window. */
     memcpy (&window[offset - windowstart], buf, count);
@@ -374,7 +382,8 @@ streaming_pread (void *handle, void *buf, uint32_t count, uint64_t offset)
   windowstart = highestwrite - window_size;
 
   if (offset < windowstart) {
-    nbdkit_error ("client seeked backwards > window size: you must increase the window size");
+    nbdkit_error ("pread: client backwards seek > window size: you must increase the window size (highestwrite=%" PRIu64 ", window_size=%" PRIi64 ")",
+                  highestwrite, window_size);
     errorstate = 1;
     errno = EIO;
     return -1;
diff --git a/tests/Makefile.am b/tests/Makefile.am
index a50e26b..cccd45b 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -172,18 +172,11 @@ test_python_LDADD = libtest.la $(LIBGUESTFS_LIBS)
 endif
 
 # streaming plugin test.
+check_PROGRAMS += test-streaming
+TESTS += test-streaming
 
-# This is disabled at the moment because the libguestfs appliance
-# kernel tries to read from the device (eg to read the partition
-# table) and the current streaming plugin cannot handle this.
-# Implementing a sliding window in the plugin would fix this. (XXX)
-EXTRA_DIST += test-streaming.c
-
-#check_PROGRAMS += test-streaming
-#TESTS += test-streaming
-#
-#test_streaming_SOURCES = test-streaming.c test.h
-#test_streaming_CFLAGS = $(WARNINGS_CFLAGS) $(LIBGUESTFS_CFLAGS)
-#test_streaming_LDADD = libtest.la $(LIBGUESTFS_LIBS)
+test_streaming_SOURCES = test-streaming.c test.h
+test_streaming_CFLAGS = $(WARNINGS_CFLAGS) $(LIBGUESTFS_CFLAGS)
+test_streaming_LDADD = libtest.la $(LIBGUESTFS_LIBS)
 
 endif
diff --git a/tests/test-streaming.c b/tests/test-streaming.c
index 1631c19..4610fb9 100644
--- a/tests/test-streaming.c
+++ b/tests/test-streaming.c
@@ -48,7 +48,7 @@
 
 #include "test.h"
 
-static char data[4096];
+static char data[1024];
 
 int
 main (int argc, char *argv[])
@@ -69,6 +69,8 @@ main (int argc, char *argv[])
 
   if (test_start_nbdkit (NBDKIT_PLUGIN ("streaming"),
                          "pipe=streaming.fifo",
+                         "size=128k",
+                         "window=128k",
                          NULL) == -1)
     exit (EXIT_FAILURE);
 
@@ -121,14 +123,10 @@ main (int argc, char *argv[])
     exit (EXIT_FAILURE);
 
   /* Write linearly to the virtual disk. */
-  for (i = 0; i < 10; ++i) {
-    memset (data, i+1, sizeof data);
-
-    /* Note that we deliberately skip forwards, in order to
-     * exercise seeking code in the streaming plugin.
-     */
+  memset (data, 1, sizeof data);
+  for (i = 0; i < 32; ++i) {
     guestfs_pwrite_device (g, "/dev/sda", data, sizeof data,
-                           (2 * i) * sizeof data);
+                           i * sizeof data);
   }
 
   if (guestfs_shutdown (g) == -1)
@@ -148,7 +146,7 @@ main (int argc, char *argv[])
   }
   md5[32] = '\0';
 
-  if (strcmp (md5, "0123456789abcdef0123456789abcdef") != 0) {
+  if (strcmp (md5, "51ae9fa5fb90e9d51c4f1b4260285c99") != 0) {
     fprintf (stderr, "unexpected hash: %s\n", md5);
     exit (EXIT_FAILURE);
   }
-- 
2.0.4