GUACAMOLE-249: Redirect FreeRDP log messages to debug level of guac_client_log().

src/protocols/rdp/Makefile.am

@@ -66,6 +66,7 @@ libguac_client_rdp_la_SOURCES =                  \
     keyboard/decompose.c                         \
     keyboard/keyboard.c                          \
     keyboard/keymap.c                            \
+    log.c                                        \
     ls.c                                         \
     plugins/channels.c                           \
     plugins/ptr-string.c                         \
@@ -107,6 +108,7 @@ noinst_HEADERS =                                 \
     keyboard/decompose.h                         \
     keyboard/keyboard.h                          \
     keyboard/keymap.h                            \
+    log.h                                        \
     ls.h                                         \
     plugins/channels.h                           \
     plugins/guacai/guacai-messages.h             \

src/protocols/rdp/client.c

@@ -23,6 +23,7 @@
 #include "client.h"
 #include "common/recording.h"
 #include "fs.h"
+#include "log.h"
 #include "rdp.h"
 #include "user.h"
 
@@ -40,6 +41,7 @@
 #include <guacamole/audio.h>
 #include <guacamole/client.h>
 #include <guacamole/socket.h>
+#include <winpr/wlog.h>
 
 #include <pthread.h>
 #include <stdlib.h>
@@ -60,6 +62,9 @@ int guac_client_init(guac_client* client, int argc, char** argv) {
     /* Init display update module */
     rdp_client->disp = guac_rdp_disp_alloc();
 
+    /* Redirect FreeRDP log messages to guac_client_log() */
+    guac_rdp_redirect_wlog(client);
+
     /* Recursive attribute for locks */
     pthread_mutexattr_init(&(rdp_client->attributes));
     pthread_mutexattr_settype(&(rdp_client->attributes),

src/protocols/rdp/log.c

@@ -0,0 +1,71 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+#include <guacamole/client.h>
+#include <winpr/wlog.h>
+
+/**
+ * The guac_client that should be used within this process for FreeRDP log
+ * messages. As all Guacamole connections are isolated at the process level,
+ * this will only ever be set to the guac_client of the current process'
+ * connection.
+ */
+static guac_client* current_client = NULL;
+
+/**
+ * Logs the text data within the given message to the logging facilities of the
+ * guac_client currently stored under current_client (the guac_client of the
+ * current process).
+ *
+ * @param message
+ *     The message to log.
+ *
+ * @return
+ *     TRUE if the message was successfully logged, FALSE otherwise.
+ */
+static BOOL guac_rdp_wlog_text_message(const wLogMessage* message) {
+
+    /* Fail if log not yet redirected */
+    if (current_client == NULL)
+        return FALSE;
+
+    /* Log all received messages at the debug level */
+    guac_client_log(current_client, GUAC_LOG_DEBUG, "%s", message->TextString);
+    return TRUE;
+
+}
+
+void guac_rdp_redirect_wlog(guac_client* client) {
+
+    wLogCallbacks callbacks = {
+        .message = guac_rdp_wlog_text_message
+    };
+
+    current_client = client;
+
+    /* Reconfigure root logger to use callback appender */
+    wLog* root = WLog_GetRoot();
+    WLog_SetLogAppenderType(root, WLOG_APPENDER_CALLBACK);
+
+    /* Set appender callbacks to our own */
+    wLogAppender* appender = WLog_GetLogAppender(root);
+    WLog_ConfigureAppender(appender, "callbacks", &callbacks);
+
+}
+

src/protocols/rdp/log.h

@@ -0,0 +1,35 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+#ifndef GUAC_RDP_LOG_H
+#define GUAC_RDP_LOG_H
+
+#include <guacamole/client.h>
+
+/**
+ * Redirects the core FreeRDP logging facility, wLog, such that it logs all
+ * messages at the debug level using guac_client_log().
+ *
+ * @param client
+ *     The guac_client that should receive all log messages.
+ */
+void guac_rdp_redirect_wlog(guac_client* client);
+
+#endif
+