[Spice-devel] [(spice) PATCHv2 RFC 2/2] TIOCOUTQ -> SIOCOUTQ and portability ifdefs

[Nahum Shalman]

The ioctl on sockets is actually named SIOCOUTQ though its value
is identical to TIOCOUTQ which is for terminals.
SIOCOUTQ is linux specific so we add a header check and ifdef based
on the presence of the header
This prevents bogus ioctls on non-Linux platforms
---
 configure.ac         |    1 +
 server/red_channel.c |   13 +++++++++++--
 2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/configure.ac b/configure.ac
index a549ed9..fa1ba31 100644
--- a/configure.ac
+++ b/configure.ac
@@ -51,6 +51,7 @@ PKG_PROG_PKG_CONFIG
 
 AC_CHECK_HEADERS([sys/time.h])
 AC_CHECK_HEADERS([execinfo.h])
+AC_CHECK_HEADERS([linux/sockios.h])
 AC_FUNC_ALLOCA
 
 AC_DEFINE([__STDC_FORMAT_MACROS],[],[Force definition of format macros for C++])
diff --git a/server/red_channel.c b/server/red_channel.c
index 85d7ebc..31c991b 100644
--- a/server/red_channel.c
+++ b/server/red_channel.c
@@ -30,6 +30,9 @@
 #include <unistd.h>
 #include <errno.h>
 #include <sys/ioctl.h>
+#ifdef HAVE_LINUX_SOCKIOS_H
+#include <linux/sockios.h> /* SIOCOUTQ */
+#endif
 
 #include "common/generated_server_marshallers.h"
 #include "common/ring.h"
@@ -722,9 +725,11 @@ static void red_channel_client_ping_timer(void *opaque)
 
     spice_assert(rcc->latency_monitor.state == PING_STATE_TIMER);
     red_channel_client_cancel_ping_timer(rcc);
+
+#ifdef HAVE_LINUX_SOCKIOS_H /* SIOCOUTQ is a Linux only ioctl on sockets. */
     /* retrieving the occupied size of the socket's tcp snd buffer (unacked + unsent) */
-    if (ioctl(rcc->stream->socket, TIOCOUTQ, &so_unsent_size) == -1) {
-        spice_printerr("ioctl(TIOCOUTQ) failed, %s", strerror(errno));
+    if (ioctl(rcc->stream->socket, SIOCOUTQ, &so_unsent_size) == -1) {
+        spice_printerr("ioctl(SIOCOUTQ) failed, %s", strerror(errno));
     }
     if (so_unsent_size > 0) {
         /* tcp snd buffer is still occupied. rescheduling ping */
@@ -732,6 +737,10 @@ static void red_channel_client_ping_timer(void *opaque)
     } else {
         red_channel_client_push_ping(rcc);
     }
+#else /* ifdef HAVE_LINUX_SOCKIOS_H */
+    /* More portable alternative code path (less accurate but avoids bogus ioctls)*/
+    red_channel_client_push_ping(rcc);
+#endif /* ifdef HAVE_LINUX_SOCKIOS_H */
 }
 
 RedChannelClient *red_channel_client_create(int size, RedChannel *channel, RedClient  *client,
-- 
1.7.7.6