GUACAMOLE-288: Add support for multi-monitor connections.

src/libguac/guacamole/user-fntypes.h

@@ -220,12 +220,15 @@ typedef int guac_user_clipboard_handler(guac_user* user, guac_stream* stream,
  * @param height
  *     The desired height of the display, in pixels.
  *
+ * @param monitors
+ *     The count of monitors.
+ * 
  * @return
  *     Zero if the size event has been successfully handled, non-zero
  *     otherwise.
  */
 typedef int guac_user_size_handler(guac_user* user,
-        int width, int height);
+        int width, int height, int monitors);
 
 /**
  * Handler for Guacamole file streams received from a user. Each such file

src/libguac/guacamole/user.h

@@ -293,7 +293,7 @@ struct guac_user {
      *
      * Example:
      * @code
-     *     int size_handler(guac_user* user, int width, int height);
+     *     int size_handler(guac_user* user, int width, int height, int monitor);
      *
      *     int guac_user_init(guac_user* user, int argc, char** argv) {
      *         user->size_handler = size_handler;

src/libguac/user-handlers.c

@@ -372,7 +372,8 @@ int __guac_handle_size(guac_user* user, int argc, char** argv) {
         return user->size_handler(
             user,
             atoi(argv[0]), /* width */
-            atoi(argv[1])  /* height */
+            atoi(argv[1]), /* height */
+            (argc == 3 ? atoi(argv[2]) : 1) /* Monitors count */
         );
     return 0;
 }

src/protocols/kubernetes/input.c

@@ -70,7 +70,7 @@ int guac_kubernetes_user_key_handler(guac_user* user, int keysym, int pressed) {
 
 }
 
-int guac_kubernetes_user_size_handler(guac_user* user, int width, int height) {
+int guac_kubernetes_user_size_handler(guac_user* user, int width, int height, int monitors) {
 
     /* Get terminal */
     guac_client* client = user->client;

src/protocols/rdp/channels/disp.c

@@ -44,9 +44,10 @@ guac_rdp_disp* guac_rdp_disp_alloc(guac_client* client) {
 
     /* No requests have been made */
     disp->last_request = guac_timestamp_current();
-    disp->requested_width  = 0;
-    disp->requested_height = 0;
-    disp->reconnect_needed = 0;
+    disp->requested_width    = 0;
+    disp->requested_height   = 0;
+    disp->reconnect_needed   = 0;
+    disp->requested_monitors = 1;
 
     return disp;
 
@@ -88,7 +89,7 @@ static void guac_rdp_disp_channel_connected(rdpContext* context,
     /* Init module with current display size */
     guac_rdp_disp_set_size(guac_disp, rdp_client->settings,
             context->instance, guac_rdp_get_width(context->instance),
-            guac_rdp_get_height(context->instance));
+            guac_rdp_get_height(context->instance), 1);
 
     /* Store reference to the display update plugin once it's connected */
     DispClientContext* disp = (DispClientContext*) args->pInterface;
@@ -151,7 +152,7 @@ void guac_rdp_disp_load_plugin(rdpContext* context) {
 }
 
 void guac_rdp_disp_set_size(guac_rdp_disp* disp, guac_rdp_settings* settings,
-        freerdp* rdp_inst, int width, int height) {
+        freerdp* rdp_inst, int width, int height, int monitors) {
 
     guac_rect resize = {
         .left = 0,
@@ -180,6 +181,7 @@ void guac_rdp_disp_set_size(guac_rdp_disp* disp, guac_rdp_settings* settings,
     /* Store deferred size */
     disp->requested_width = width;
     disp->requested_height = height;
+    disp->requested_monitors = monitors;
 
     /* Send display update notification if possible */
     guac_rdp_disp_update_size(disp, settings, rdp_inst);
@@ -191,6 +193,15 @@ void guac_rdp_disp_update_size(guac_rdp_disp* disp,
 
     int width = disp->requested_width;
     int height = disp->requested_height;
+    int monitors_count = disp->requested_monitors;
+
+    /* Prevent opening too many monitors than allowed */
+    if (settings->max_secondary_monitors + 1 < monitors_count)
+        monitors_count = settings->max_secondary_monitors + 1;
+
+    /* At least one monitor is required */
+    if (monitors_count < 1)
+        monitors_count = 1;
 
     /* Do not update size if no requests have been received */
     if (width == 0 || height == 0)
@@ -204,7 +215,7 @@ void guac_rdp_disp_update_size(guac_rdp_disp* disp,
 
     /* Do NOT send requests unless the size will change */
     if (rdp_inst != NULL
-            && width == guac_rdp_get_width(rdp_inst)
+            && width * monitors_count == guac_rdp_get_width(rdp_inst)
             && height == guac_rdp_get_height(rdp_inst))
         return;
 
@@ -221,32 +232,46 @@ void guac_rdp_disp_update_size(guac_rdp_disp* disp,
 
     }
 
-    else if (settings->resize_method == GUAC_RESIZE_DISPLAY_UPDATE) {
-        DISPLAY_CONTROL_MONITOR_LAYOUT monitors[1] = {{
-            .Flags  = 0x1, /* DISPLAYCONTROL_MONITOR_PRIMARY */
-            .Left = 0,
-            .Top = 0,
-            .Width  = width,
-            .Height = height,
-            .PhysicalWidth = 0,
-            .PhysicalHeight = 0,
-            .Orientation = 0,
-            .DesktopScaleFactor = 0,
-            .DeviceScaleFactor = 0
-        }};
-
-        /* Send display update notification if display channel is connected */
-        if (disp->disp != NULL) {
-
-            guac_client* client = disp->client;
-            guac_rdp_client* rdp_client = (guac_rdp_client*) client->data;
-
-            pthread_mutex_lock(&(rdp_client->message_lock));
-            disp->disp->SendMonitorLayout(disp->disp, 1, monitors);
-            pthread_mutex_unlock(&(rdp_client->message_lock));
+    /* Send display update notification if display channel is connected */
+    else if (settings->resize_method == GUAC_RESIZE_DISPLAY_UPDATE
+                && disp->disp != NULL) {
+
+        /* Init monitors layout */
+        DISPLAY_CONTROL_MONITOR_LAYOUT* monitors;
+        monitors = guac_mem_alloc(monitors_count * sizeof(DISPLAY_CONTROL_MONITOR_LAYOUT));
+
+        for (int i = 0; i < monitors_count; i++) {
+
+            /* First monitor is the primary */
+            int primary_monitor = (i == 0 ? 1 : 0);
 
+            /* Shift each monitor to the right */
+            int monitor_left = i * width;
+
+            /* Get current monitor */
+            DISPLAY_CONTROL_MONITOR_LAYOUT* monitor = &monitors[i];
+
+            /* Set current monitor properties */
+            monitor->Flags = primary_monitor;
+            monitor->Left = monitor_left;
+            monitor->Top = 0;
+            monitor->Width = width;
+            monitor->Height = height;
+            monitor->Orientation = 0;
+            monitor->PhysicalWidth = 0;
+            monitor->PhysicalHeight = 0;
         }
 
+        /* Send display update notification */
+        guac_client* client = disp->client;
+        guac_rdp_client* rdp_client = (guac_rdp_client*) client->data;
+
+        pthread_mutex_lock(&(rdp_client->message_lock));
+        disp->disp->SendMonitorLayout(disp->disp, monitors_count, monitors);
+        pthread_mutex_unlock(&(rdp_client->message_lock));
+
+        guac_mem_free(monitors);
+
     }
 
 }

src/protocols/rdp/channels/disp.h

@@ -74,6 +74,11 @@ typedef struct guac_rdp_disp {
      */
     int requested_height;
 
+    /**
+     * The number of monitors requested.
+     */
+    int requested_monitors;
+
     /**
      * Whether the size has changed and the RDP connection must be closed and
      * reestablished.
@@ -154,9 +159,12 @@ void guac_rdp_disp_load_plugin(rdpContext* context);
  *     The desired display height, in pixels. Due to the restrictions of the
  *     RDP display update channel, this will be constrained to the range of 200
  *     through 8192 inclusive.
+ * 
+ * @param monitors
+ *     The count of monitors.
  */
 void guac_rdp_disp_set_size(guac_rdp_disp* disp, guac_rdp_settings* settings,
-        freerdp* rdp_inst, int width, int height);
+        freerdp* rdp_inst, int width, int height, int monitors);
 
 /**
  * Sends an actual display update request to the RDP server based on previous

src/protocols/rdp/client.c

@@ -42,6 +42,7 @@
 #include <guacamole/mem.h>
 #include <guacamole/recording.h>
 #include <guacamole/rwlock.h>
+#include <guacamole/string.h>
 
 #include <dirent.h>
 #include <errno.h>
@@ -130,6 +131,16 @@ static int guac_rdp_join_pending_handler(guac_client* client) {
     /* Bring user up to date with any registered static channels */
     guac_rdp_pipe_svc_send_pipes(client, broadcast_socket);
 
+    /* Get max secondary monitors */
+    char* max_monitors = guac_mem_alloc(12);
+    guac_itoa(max_monitors,
+            (unsigned int) rdp_client->settings->max_secondary_monitors);
+
+    /* Send current max allowed secondary monitors */
+    guac_client_stream_argv(client, broadcast_socket, "text/plain",
+            "secondary-monitors", max_monitors);
+    guac_mem_free(max_monitors);
+
     /* Synchronize with current display */
     if (rdp_client->display != NULL) {
         guac_display_dup(rdp_client->display, broadcast_socket);

src/protocols/rdp/input.c

@@ -191,7 +191,7 @@ int guac_rdp_user_key_handler(guac_user* user, int keysym, int pressed) {
 
 }
 
-int guac_rdp_user_size_handler(guac_user* user, int width, int height) {
+int guac_rdp_user_size_handler(guac_user* user, int width, int height, int monitors) {
 
     guac_client* client = user->client;
     guac_rdp_client* rdp_client = (guac_rdp_client*) client->data;
@@ -203,7 +203,7 @@ int guac_rdp_user_size_handler(guac_user* user, int width, int height) {
     height = height * settings->resolution / user->info.optimal_resolution;
 
     /* Send display update */
-    guac_rdp_disp_set_size(rdp_client->disp, settings, rdp_inst, width, height);
+    guac_rdp_disp_set_size(rdp_client->disp, settings, rdp_inst, width, height, monitors);
 
     return 0;
 

src/protocols/rdp/rdp.c

@@ -607,7 +607,6 @@ static int guac_rdp_handle_connection(guac_client* client) {
         guac_rdp_disp_update_size(rdp_client->disp, settings, rdp_inst);
 
         /* Wait for data and construct a reasonable frame */
-
         int wait_result = rdp_guac_client_wait_for_messages(client, GUAC_RDP_MESSAGE_CHECK_INTERVAL);
         if (wait_result < 0)
             break;

src/protocols/rdp/settings.c

@@ -128,6 +128,7 @@ const char* GUAC_RDP_CLIENT_ARGS[] = {
     "create-recording-path",
     "recording-write-existing",
     "resize-method",
+    "secondary-monitors",
     "enable-audio-input",
     "enable-touch",
     "read-only",
@@ -598,6 +599,12 @@ enum RDP_ARGS_IDX {
      */
     IDX_RESIZE_METHOD,
 
+    /**
+     * The maximum allowed count of secondary monitors.
+     * 0 to disable.
+     */
+    IDX_SECONDARY_MONITORS,
+
     /**
      * "true" if audio input (microphone) should be enabled for the RDP
      * connection, "false" or blank otherwise.
@@ -1234,6 +1241,11 @@ guac_rdp_settings* guac_rdp_parse_args(guac_user* user,
         settings->resize_method = GUAC_RESIZE_NONE;
     }
 
+    /* Maximum secondary monitors (default 0 = disabled) */
+    settings->max_secondary_monitors =
+        guac_user_parse_args_int(user, GUAC_RDP_CLIENT_ARGS, argv,
+                IDX_SECONDARY_MONITORS, 0);
+
     /* RDP Graphics Pipeline enable/disable */
     settings->enable_gfx =
         !guac_user_parse_args_boolean(user, GUAC_RDP_CLIENT_ARGS, argv,
@@ -1729,6 +1741,7 @@ void guac_rdp_push_settings(guac_client* client,
     freerdp_settings_set_uint32(rdp_settings, FreeRDP_OsMajorType, OSMAJORTYPE_UNSPECIFIED);
     freerdp_settings_set_uint32(rdp_settings, FreeRDP_OsMinorType, OSMINORTYPE_UNSPECIFIED);
     freerdp_settings_set_bool(rdp_settings, FreeRDP_DesktopResize, TRUE);
+    freerdp_settings_set_bool(rdp_settings, FreeRDP_UseMultimon, TRUE);
 
     /* Claim support only for specific updates, independent of FreeRDP defaults */
 	BYTE* order_support = freerdp_settings_get_pointer_writable(rdp_settings, FreeRDP_OrderSupport);
@@ -1975,6 +1988,7 @@ void guac_rdp_push_settings(guac_client* client,
     rdp_settings->OsMajorType = OSMAJORTYPE_UNSPECIFIED;
     rdp_settings->OsMinorType = OSMINORTYPE_UNSPECIFIED;
     rdp_settings->DesktopResize = TRUE;
+    rdp_settings->UseMultimon = TRUE;
 
     /* Claim support only for specific updates, independent of FreeRDP defaults */
     ZeroMemory(rdp_settings->OrderSupport, GUAC_RDP_ORDER_SUPPORT_LENGTH);

src/protocols/rdp/settings.h

@@ -596,6 +596,11 @@ typedef struct guac_rdp_settings {
      */
     guac_rdp_resize_method resize_method;
 
+    /**
+     * The maximum allowed count of secondary monitors.
+     */
+    int max_secondary_monitors;
+
     /**
      * Whether audio input (microphone) is enabled.
      */

src/protocols/ssh/input.c

@@ -68,7 +68,7 @@ int guac_ssh_user_key_handler(guac_user* user, int keysym, int pressed) {
     return 0;
 }
 
-int guac_ssh_user_size_handler(guac_user* user, int width, int height) {
+int guac_ssh_user_size_handler(guac_user* user, int width, int height, int monitors) {
 
     /* Get terminal */
     guac_client* client = user->client;

src/protocols/telnet/input.c

@@ -120,7 +120,7 @@ int guac_telnet_user_key_handler(guac_user* user, int keysym, int pressed) {
 
 }
 
-int guac_telnet_user_size_handler(guac_user* user, int width, int height) {
+int guac_telnet_user_size_handler(guac_user* user, int width, int height, int monitors) {
 
     /* Get terminal */
     guac_client* client = user->client;

src/protocols/vnc/input.c

@@ -65,7 +65,7 @@ int guac_vnc_user_key_handler(guac_user* user, int keysym, int pressed) {
 }
 
 #ifdef LIBVNC_HAS_SIZE_MSG
-int guac_vnc_user_size_handler(guac_user* user, int width, int height) {
+int guac_vnc_user_size_handler(guac_user* user, int width, int height, int monitors) {
 
     guac_user_log(user, GUAC_LOG_TRACE, "Running user size handler.");