From 7d557c2a53a5baa7d566e5d8ffa467dd1bc382db Mon Sep 17 00:00:00 2001

From: Eric Blake <eblake@redhat.com>

Date: Wed, 19 Jul 2017 18:02:01 +0200

Subject: [PATCH 04/17] nbd: make nbd_drop public

RH-Author: Eric Blake <eblake@redhat.com>

Message-id: <20170719180202.23329-4-eblake@redhat.com>

Patchwork-id: 75814

O-Subject: [RHEV-7.4.z qemu-kvm-rhev PATCH 3/4] nbd: make nbd_drop public

Bugzilla: 1473638

RH-Acked-by: Stefan Hajnoczi <stefanha@redhat.com>

RH-Acked-by: Paolo Bonzini <pbonzini@redhat.com>

RH-Acked-by: Jeffrey Cody <jcody@redhat.com>

From: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>

Following commit will reuse it for nbd server too.

Reviewed-by: Eric Blake <eblake@redhat.com>

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>

Message-Id: <20170602150150.258222-3-vsementsov@virtuozzo.com>

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

(cherry picked from commit 44298024d30ad36439707b89715a76333f58791b)

 Conflicts:

	nbd/client.c, nbd/nbd_internal.h, nbd/common.c - missing errp

	addition (e44ed99) and bulk rename (d1fdf25)

Signed-off-by: Eric Blake <eblake@redhat.com>

Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>

---

 nbd/client.c       | 32 +++-----------------------------

 nbd/common.c       | 26 ++++++++++++++++++++++++++

 nbd/nbd-internal.h |  2 ++

 3 files changed, 31 insertions(+), 29 deletions(-)

diff --git a/nbd/client.c b/nbd/client.c

index 6b74a62..1652f28 100644

--- a/nbd/client.c

+++ b/nbd/client.c

@@ -86,32 +86,6 @@ static QTAILQ_HEAD(, NBDExport) exports = QTAILQ_HEAD_INITIALIZER(exports);

 */

-/* Discard length bytes from channel.  Return -errno on failure and 0 on

- * success*/

-static int drop_sync(QIOChannel *ioc, size_t size)

-{

-    ssize_t ret = 0;

-    char small[1024];

-    char *buffer;

-

-    buffer = sizeof(small) >= size ? small : g_malloc(MIN(65536, size));

-    while (size > 0) {

-        ssize_t count = MIN(65536, size);

-        ret = read_sync(ioc, buffer, MIN(65536, size));

-

-        if (ret < 0) {

-            goto cleanup;

-        }

-        size -= count;

-    }

-

- cleanup:

-    if (buffer != small) {

-        g_free(buffer);

-    }

-    return ret;

-}

-

 /* Send an option request.

  *

  * The request is for option @opt, with @data containing @len bytes of

@@ -333,7 +307,7 @@ static int nbd_receive_list(QIOChannel *ioc, const char *want, bool *match,

         return -1;

     }

     if (namelen != strlen(want)) {

-        if (drop_sync(ioc, len) < 0) {

+        if (nbd_drop(ioc, len) < 0) {

             error_setg(errp, "failed to skip export name with wrong length");

             nbd_send_opt_abort(ioc);

             return -1;

@@ -349,7 +323,7 @@ static int nbd_receive_list(QIOChannel *ioc, const char *want, bool *match,

     }

     name[namelen] = '\0';

     len -= namelen;

-    if (drop_sync(ioc, len) < 0) {

+    if (nbd_drop(ioc, len) < 0) {

         error_setg(errp, "failed to read export description");

         nbd_send_opt_abort(ioc);

         return -1;

@@ -616,7 +590,7 @@ int nbd_receive_negotiate(QIOChannel *ioc, const char *name, uint16_t *flags,

     }

     TRACE("Size is %" PRIu64 ", export flags %" PRIx16, *size, *flags);

-    if (zeroes && drop_sync(ioc, 124) < 0) {

+    if (zeroes && nbd_drop(ioc, 124) < 0) {

         error_setg(errp, "Failed to read reserved block");

         goto fail;

     }

diff --git a/nbd/common.c b/nbd/common.c

index 4db45b3..9a54010 100644

--- a/nbd/common.c

+++ b/nbd/common.c

@@ -71,6 +71,32 @@ ssize_t nbd_wr_syncv(QIOChannel *ioc,

     return done;

 }

+/* Discard length bytes from channel.  Return -errno on failure and 0 on

+ * success */

+int nbd_drop(QIOChannel *ioc, size_t size)

+{

+    ssize_t ret = 0;

+    char small[1024];

+    char *buffer;

+

+    buffer = sizeof(small) >= size ? small : g_malloc(MIN(65536, size));

+    while (size > 0) {

+        ssize_t count = MIN(65536, size);

+        ret = read_sync(ioc, buffer, MIN(65536, size));

+

+        if (ret < 0) {

+            goto cleanup;

+        }

+        size -= count;

+    }

+

+ cleanup:

+    if (buffer != small) {

+        g_free(buffer);

+    }

+    return ret;

+}

+

 void nbd_tls_handshake(QIOTask *task,

                        void *opaque)

diff --git a/nbd/nbd-internal.h b/nbd/nbd-internal.h

index e6bbc7c..c02378c 100644

--- a/nbd/nbd-internal.h

+++ b/nbd/nbd-internal.h

@@ -149,4 +149,6 @@ struct NBDTLSHandshakeData {

 void nbd_tls_handshake(QIOTask *task,

                        void *opaque);

+int nbd_drop(QIOChannel *ioc, size_t size);

+

 #endif

-- 

1.8.3.1