[Spice-devel] [spice-gtk v1 4/4] channel-display: Limit number of streams that can be created

[Frediano Ziglio]

> 
> From: Victor Toso <me at victortoso.com>
> 
> Using the limit SPICE_MAX_NUM_STREAMS introduced in spice-protocol
> 0.12.14 to fix the amount of streams we might be working currently.
> 
> With this change, let's create the streams array on _init() and free
> it on _finalize() to avoid dealing with too many checks everywhere.
> 
> Note that this patch removes the nstreams as the array size is fixed.
> 
> Signed-off-by: Victor Toso <victortoso at redhat.com>
> ---
>  configure.ac          |  2 +-
>  src/channel-display.c | 28 +++++++---------------------
>  2 files changed, 8 insertions(+), 22 deletions(-)
> 
> diff --git a/configure.ac b/configure.ac
> index a9a7eb9..768e180 100644
> --- a/configure.ac
> +++ b/configure.ac
> @@ -86,7 +86,7 @@ AC_CHECK_LIBM
>  AC_SUBST(LIBM)
>  
>  AC_CONFIG_SUBDIRS([spice-common])
> -PKG_CHECK_MODULES([SPICE_PROTOCOL], [spice-protocol >= 0.12.13])
> +PKG_CHECK_MODULES([SPICE_PROTOCOL], [spice-protocol >= 0.12.14])
>  
>  COMMON_CFLAGS='-I${top_builddir}/spice-common/ -I${top_srcdir}/spice-common/
>  ${SPICE_PROTOCOL_CFLAGS}'
>  AC_SUBST(COMMON_CFLAGS)
> diff --git a/src/channel-display.c b/src/channel-display.c
> index 5329ed0..50c896d 100644
> --- a/src/channel-display.c
> +++ b/src/channel-display.c
> @@ -64,7 +64,6 @@ struct _SpiceDisplayChannelPrivate {
>      SpiceImageSurfaces          image_surfaces;
>      SpiceGlzDecoderWindow       *glz_window;
>      display_stream              **streams;
> -    int                         nstreams;
>      gboolean                    mark;
>      guint                       mark_false_event_id;
>      GArray                      *monitors;
> @@ -169,6 +168,7 @@ static void spice_display_channel_finalize(GObject
> *object)
>      clear_surfaces(SPICE_CHANNEL(object), FALSE);
>      g_hash_table_unref(c->surfaces);
>      clear_streams(SPICE_CHANNEL(object));
> +    g_clear_pointer(&c->streams, g_free);
>      g_clear_pointer(&c->palettes, cache_free);
>  
>      if (G_OBJECT_CLASS(spice_display_channel_parent_class)->finalize)
> @@ -862,6 +862,7 @@ static void
> spice_display_channel_init(SpiceDisplayChannel *channel)
>  
>      c = channel->priv = SPICE_DISPLAY_CHANNEL_GET_PRIVATE(channel);
>  
> +    c->streams = g_new0(display_stream *, SPICE_MAX_NUM_STREAMS);
>      c->surfaces = g_hash_table_new_full(NULL, NULL, NULL, destroy_surface);
>      c->image_cache.ops = &image_cache_ops;
>      c->palette_cache.ops = &palette_cache_ops;
> @@ -1209,8 +1210,7 @@ static display_stream *get_stream_by_id(SpiceChannel
> *channel, uint32_t id)
>  {
>      SpiceDisplayChannelPrivate *c = SPICE_DISPLAY_CHANNEL(channel)->priv;
>  
> -    if (c != NULL && c->streams != NULL && id < c->nstreams &&
> -        c->streams[id] != NULL) {
> +    if (c != NULL && id < SPICE_MAX_NUM_STREAMS && c->streams[id] != NULL) {
>          return c->streams[id];
>      }
>  
> @@ -1263,7 +1263,7 @@ static void destroy_stream(SpiceChannel *channel, int
> id)
>  
>      g_return_if_fail(c != NULL);
>      g_return_if_fail(c->streams != NULL);
> -    g_return_if_fail(c->nstreams > id);
> +    g_return_if_fail(id < SPICE_MAX_NUM_STREAMS);

As int could potentially also be <0, maybe better change these IDs to make sure
there are unsigned?

>  
>      g_clear_pointer(&c->streams[id], display_stream_destroy);
>  }
> @@ -1274,18 +1274,7 @@ static void display_handle_stream_create(SpiceChannel
> *channel, SpiceMsgIn *in)
>      SpiceMsgDisplayStreamCreate *op = spice_msg_in_parsed(in);
>  
>      CHANNEL_DEBUG(channel, "%s: id %u", __FUNCTION__, op->id);
> -
> -    if (op->id >= c->nstreams) {
> -        int n = c->nstreams;
> -        if (!c->nstreams) {
> -            c->nstreams = 1;
> -        }
> -        while (op->id >= c->nstreams) {
> -            c->nstreams *= 2;
> -        }
> -        c->streams = realloc(c->streams, c->nstreams *
> sizeof(c->streams[0]));
> -        memset(c->streams + n, 0, (c->nstreams - n) *
> sizeof(c->streams[0]));
> -    }
> +    g_return_if_fail(op->id < SPICE_MAX_NUM_STREAMS);
>      g_return_if_fail(c->streams[op->id] == NULL);
>  
>      c->streams[op->id] = display_stream_create(channel, op->id,
>      op->surface_id,
> @@ -1474,7 +1463,7 @@ static void
> display_session_mm_time_reset_cb(SpiceSession *session, gpointer dat
>  
>      CHANNEL_DEBUG(channel, "%s", __FUNCTION__);
>  
> -    for (i = 0; i < c->nstreams; i++) {
> +    for (i = 0; i < SPICE_MAX_NUM_STREAMS; i++) {
>          display_stream *st;
>  
>          if (c->streams[i] == NULL) {
> @@ -1625,14 +1614,11 @@ static void display_stream_destroy(gpointer
> st_pointer)
>  
>  static void clear_streams(SpiceChannel *channel)
>  {
> -    SpiceDisplayChannelPrivate *c = SPICE_DISPLAY_CHANNEL(channel)->priv;
>      int i;
>  
> -    for (i = 0; i < c->nstreams; i++) {
> +    for (i = 0; i < SPICE_MAX_NUM_STREAMS; i++) {
>          destroy_stream(channel, i);
>      }
> -    g_clear_pointer(&c->streams, g_free);
> -    c->nstreams = 0;
>  }
>  
>  /* coroutine context */

Frediano