GUACAMOLE-175: Merge move of guacd core into library.

Makefile.am

@@ -22,6 +22,7 @@ ACLOCAL_AMFLAGS = -I m4
 # Subprojects
 DIST_SUBDIRS =           \
     src/libguac          \
+    src/libguacd         \
     src/common           \
     src/common-ssh       \
     src/terminal         \
@@ -33,9 +34,10 @@ DIST_SUBDIRS =           \
     src/protocols/vnc    \
     tests
 
-SUBDIRS =       \
+SUBDIRS =        \
-    src/libguac \
+    src/libguac  \
-    src/common  \
+    src/common   \
+    src/libguacd \
     tests
 
 if ENABLE_COMMON_SSH

configure.ac

@@ -119,6 +119,10 @@ AC_SUBST([LIBGUAC_INCLUDE], '-I$(top_srcdir)/src/libguac')
 AC_SUBST([COMMON_LTLIB],   '$(top_builddir)/src/common/libguac_common.la')
 AC_SUBST([COMMON_INCLUDE], '-I$(top_srcdir)/src/common')
 
+# Common utility library for guacd implementations
+AC_SUBST([LIBGUACD_LTLIB],   '$(top_builddir)/src/libguacd/libguacd.la')
+AC_SUBST([LIBGUACD_INCLUDE], '-I$(top_srcdir)/src/libguacd')
+
 # Common base SSH client
 AC_SUBST([COMMON_SSH_LTLIB],   '$(top_builddir)/src/common-ssh/libguac_common_ssh.la')
 AC_SUBST([COMMON_SSH_INCLUDE], '-I$(top_srcdir)/src/common-ssh')
@@ -1101,6 +1105,7 @@ AC_CONFIG_FILES([Makefile
                  src/common-ssh/Makefile
                  src/terminal/Makefile
                  src/libguac/Makefile
+                 src/libguacd/Makefile
                  src/guacd/Makefile
                  src/guacenc/Makefile
                  src/protocols/rdp/Makefile

src/guacd/Makefile.am

@@ -33,8 +33,7 @@ noinst_HEADERS =  \
     log.h         \
     move-fd.h     \
     proc.h        \
-    proc-map.h    \
+    proc-map.h
-    user.h
 
 guacd_SOURCES =  \
     conf-args.c  \
@@ -45,16 +44,17 @@ guacd_SOURCES =  \
     log.c        \
     move-fd.c    \
     proc.c       \
-    proc-map.c   \
+    proc-map.c
-    user.c
 
 guacd_CFLAGS =              \
     -Werror -Wall -pedantic \
     @COMMON_INCLUDE@        \
+    @LIBGUACD_INCLUDE@      \
     @LIBGUAC_INCLUDE@
 
-guacd_LDADD =       \
+guacd_LDADD =        \
-    @COMMON_LTLIB@  \
+    @COMMON_LTLIB@   \
+    @LIBGUACD_LTLIB@ \
     @LIBGUAC_LTLIB@
 
 guacd_LDFLAGS =    \
@@ -68,12 +68,6 @@ EXTRA_DIST =         \
 
 CLEANFILES = $(init_SCRIPTS)
 
-# SSL support
-if ENABLE_SSL
-noinst_HEADERS += socket-ssl.h
-guacd_SOURCES  += socket-ssl.c
-endif
-
 # Init script
 if ENABLE_INIT
 initdir = @init_dir@

src/guacd/connection.c

@@ -22,9 +22,9 @@
 #include "connection.h"
 #include "log.h"
 #include "move-fd.h"
+#include "libguacd/user.h"
 #include "proc.h"
 #include "proc-map.h"
-#include "user.h"
 
 #include <guacamole/client.h>
 #include <guacamole/error.h>
@@ -36,7 +36,7 @@
 
 #ifdef ENABLE_SSL
 #include <openssl/ssl.h>
-#include "socket-ssl.h"
+#include "libguacd/socket-ssl.h"
 #endif
 
 #include <errno.h>

src/guacd/daemon.c

@@ -22,9 +22,9 @@
 #include "connection.h"
 #include "conf-args.h"
 #include "conf-file.h"
+#include "libguacd/user.h"
 #include "log.h"
 #include "proc-map.h"
-#include "user.h"
 
 #ifdef ENABLE_SSL
 #include <openssl/ssl.h>

src/guacd/log.c

@@ -124,31 +124,6 @@ void guacd_log_guac_error(guac_client_log_level level, const char* message) {
 
 }
 
-void guacd_client_log_guac_error(guac_client* client,
-        guac_client_log_level level, const char* message) {
-
-    if (guac_error != GUAC_STATUS_SUCCESS) {
-
-        /* If error message provided, include in log */
-        if (guac_error_message != NULL)
-            guac_client_log(client, level, "%s: %s",
-                    message,
-                    guac_error_message);
-
-        /* Otherwise just log with standard status string */
-        else
-            guac_client_log(client, level, "%s: %s",
-                    message,
-                    guac_status_string(guac_error));
-
-    }
-
-    /* Just log message if no status code */
-    else
-        guac_client_log(client, level, "%s", message);
-
-}
-
 void guacd_log_handshake_failure() {
 
     if (guac_error == GUAC_STATUS_CLOSED)

src/guacd/log.h

@@ -62,14 +62,6 @@ void guacd_client_log(guac_client* client, guac_client_log_level level,
  */
 void guacd_log_guac_error(guac_client_log_level level, const char* message);
 
-/**
- * Prints an error message using the logging facilities of the given client,
- * automatically including any information present in guac_error. This function
- * accepts parameters identically to printf.
- */
-void guacd_client_log_guac_error(guac_client* client,
-        guac_client_log_level level, const char* message);
-
 /**
  * Logs a reasonable explanatory message regarding handshake failure based on
  * the current value of guac_error.

src/guacd/proc-map.c

@@ -19,9 +19,9 @@
 
 #include "config.h"
 #include "common/list.h"
+#include "libguacd/user.h"
 #include "proc.h"
 #include "proc-map.h"
-#include "user.h"
 
 #include <guacamole/client.h>
 

src/guacd/proc-map.h

@@ -23,8 +23,8 @@
 
 #include "config.h"
 #include "common/list.h"
+#include "libguacd/user.h"
 #include "proc.h"
-#include "user.h"
 
 #include <guacamole/client.h>
 

src/guacd/proc.c

@@ -19,11 +19,11 @@
 
 #include "config.h"
 
+#include "libguacd/user.h"
 #include "log.h"
 #include "move-fd.h"
 #include "proc.h"
 #include "proc-map.h"
-#include "user.h"
 
 #include <guacamole/client.h>
 #include <guacamole/error.h>
@@ -40,216 +40,6 @@
 #include <sys/types.h>
 #include <sys/socket.h>
 
-/**
- * Copies the given array of mimetypes (strings) into a newly-allocated NULL-
- * terminated array of strings. Both the array and the strings within the array
- * are newly-allocated and must be later freed via guacd_free_mimetypes().
- *
- * @param mimetypes
- *     The array of mimetypes to copy.
- *
- * @param count
- *     The number of mimetypes in the given array.
- *
- * @return
- *     A newly-allocated, NULL-terminated array containing newly-allocated
- *     copies of each of the mimetypes provided in the original mimetypes
- *     array.
- */
-static char** guacd_copy_mimetypes(char** mimetypes, int count) {
-
-    int i;
-
-    /* Allocate sufficient space for NULL-terminated array of mimetypes */
-    char** mimetypes_copy = malloc(sizeof(char*) * (count+1));
-
-    /* Copy each provided mimetype */
-    for (i = 0; i < count; i++)
-        mimetypes_copy[i] = strdup(mimetypes[i]);
-
-    /* Terminate with NULL */
-    mimetypes_copy[count] = NULL;
-
-    return mimetypes_copy;
-
-}
-
-/**
- * Frees the given array of mimetypes, including the space allocated to each
- * mimetype string within the array. The provided array of mimetypes MUST have
- * been allocated with guacd_copy_mimetypes().
- *
- * @param mimetypes
- *     The NULL-terminated array of mimetypes to free. This array MUST have
- *     been previously allocated with guacd_copy_mimetypes().
- */
-static void guacd_free_mimetypes(char** mimetypes) {
-
-    char** current_mimetype = mimetypes;
-
-    /* Free all strings within NULL-terminated mimetype array */
-    while (*current_mimetype != NULL) {
-        free(*current_mimetype);
-        current_mimetype++;
-    }
-
-    /* Free the array itself, now that its contents have been freed */
-    free(mimetypes);
-
-}
-
-/**
- * Handles the initial handshake of a user and all subsequent I/O. This
- * function blocks until the user disconnects.
- *
- * @param user
- *     The user whose handshake and entire Guacamole protocol exchange should
- *     be handled.
- *
- * @return
- *     Zero if the user's Guacamole connection was successfully handled and
- *     the user has disconnected, or non-zero if an error prevented the user's
- *     connection from being handled properly.
- */
-static int guacd_handle_user(guac_user* user) {
-
-    guac_socket* socket = user->socket;
-    guac_client* client = user->client;
-
-    /* Send args */
-    if (guac_protocol_send_args(socket, client->args)
-            || guac_socket_flush(socket)) {
-
-        /* Log error */
-        guacd_log_handshake_failure();
-        guacd_log_guac_error(GUAC_LOG_DEBUG, "Error sending \"args\" to new user");
-
-        return 1;
-    }
-
-    guac_parser* parser = guac_parser_alloc();
-
-    /* Get optimal screen size */
-    if (guac_parser_expect(parser, socket, GUACD_USEC_TIMEOUT, "size")) {
-
-        /* Log error */
-        guacd_log_handshake_failure();
-        guacd_log_guac_error(GUAC_LOG_DEBUG, "Error reading \"size\"");
-
-        guac_parser_free(parser);
-        return 1;
-    }
-
-    /* Validate content of size instruction */
-    if (parser->argc < 2) {
-        guacd_log(GUAC_LOG_ERROR, "Received \"size\" instruction lacked required arguments.");
-        guac_parser_free(parser);
-        return 1;
-    }
-
-    /* Parse optimal screen dimensions from size instruction */
-    user->info.optimal_width  = atoi(parser->argv[0]);
-    user->info.optimal_height = atoi(parser->argv[1]);
-
-    /* If DPI given, set the client resolution */
-    if (parser->argc >= 3)
-        user->info.optimal_resolution = atoi(parser->argv[2]);
-
-    /* Otherwise, use a safe default for rough backwards compatibility */
-    else
-        user->info.optimal_resolution = 96;
-
-    /* Get supported audio formats */
-    if (guac_parser_expect(parser, socket, GUACD_USEC_TIMEOUT, "audio")) {
-
-        /* Log error */
-        guacd_log_handshake_failure();
-        guacd_log_guac_error(GUAC_LOG_DEBUG, "Error reading \"audio\"");
-
-        guac_parser_free(parser);
-        return 1;
-    }
-
-    /* Store audio mimetypes */
-    char** audio_mimetypes = guacd_copy_mimetypes(parser->argv, parser->argc);
-    user->info.audio_mimetypes = (const char**) audio_mimetypes;
-
-    /* Get supported video formats */
-    if (guac_parser_expect(parser, socket, GUACD_USEC_TIMEOUT, "video")) {
-
-        /* Log error */
-        guacd_log_handshake_failure();
-        guacd_log_guac_error(GUAC_LOG_DEBUG, "Error reading \"video\"");
-
-        guac_parser_free(parser);
-        return 1;
-    }
-
-    /* Store video mimetypes */
-    char** video_mimetypes = guacd_copy_mimetypes(parser->argv, parser->argc);
-    user->info.video_mimetypes = (const char**) video_mimetypes;
-
-    /* Get supported image formats */
-    if (guac_parser_expect(parser, socket, GUACD_USEC_TIMEOUT, "image")) {
-
-        /* Log error */
-        guacd_log_handshake_failure();
-        guacd_log_guac_error(GUAC_LOG_DEBUG, "Error reading \"image\"");
-
-        guac_parser_free(parser);
-        return 1;
-    }
-
-    /* Store image mimetypes */
-    char** image_mimetypes = guacd_copy_mimetypes(parser->argv, parser->argc);
-    user->info.image_mimetypes = (const char**) image_mimetypes;
-
-    /* Get args from connect instruction */
-    if (guac_parser_expect(parser, socket, GUACD_USEC_TIMEOUT, "connect")) {
-
-        /* Log error */
-        guacd_log_handshake_failure();
-        guacd_log_guac_error(GUAC_LOG_DEBUG, "Error reading \"connect\"");
-
-        guac_parser_free(parser);
-        return 1;
-    }
-
-    /* Acknowledge connection availability */
-    guac_protocol_send_ready(socket, client->connection_id);
-    guac_socket_flush(socket);
-
-    /* Attempt join */
-    if (guac_client_add_user(client, user, parser->argc, parser->argv))
-        guacd_log(GUAC_LOG_ERROR, "User \"%s\" could NOT join connection \"%s\"", user->user_id, client->connection_id);
-
-    /* Begin user connection if join successful */
-    else {
-
-        guacd_log(GUAC_LOG_INFO, "User \"%s\" joined connection \"%s\" (%i users now present)",
-                user->user_id, client->connection_id, client->connected_users);
-
-        /* Handle user I/O, wait for connection to terminate */
-        guacd_user_start(parser, user);
-
-        /* Remove/free user */
-        guac_client_remove_user(client, user);
-        guacd_log(GUAC_LOG_INFO, "User \"%s\" disconnected (%i users remain)", user->user_id, client->connected_users);
-
-    }
-
-    /* Free mimetype lists */
-    guacd_free_mimetypes(audio_mimetypes);
-    guacd_free_mimetypes(video_mimetypes);
-    guacd_free_mimetypes(image_mimetypes);
-
-    guac_parser_free(parser);
-
-    /* Successful disconnect */
-    return 0;
-
-}
-
 /**
  * Parameters for the user thread.
  */

src/guacd/user.c

@@ -1,113 +0,0 @@
-/*
- * 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 "config.h"
-
-#include "log.h"
-#include "user.h"
-
-#include <guacamole/client.h>
-#include <guacamole/error.h>
-#include <guacamole/parser.h>
-#include <guacamole/protocol.h>
-#include <guacamole/socket.h>
-#include <guacamole/user.h>
-
-#include <pthread.h>
-#include <stdlib.h>
-
-void* guacd_user_input_thread(void* data) {
-
-    guacd_user_input_thread_params* params = (guacd_user_input_thread_params*) data;
-    guac_user* user = params->user;
-    guac_parser* parser = params->parser;
-    guac_client* client = user->client;
-    guac_socket* socket = user->socket;
-
-    /* Guacamole user input loop */
-    while (client->state == GUAC_CLIENT_RUNNING && user->active) {
-
-        /* Read instruction, stop on error */
-        if (guac_parser_read(parser, socket, GUACD_USEC_TIMEOUT)) {
-
-            if (guac_error == GUAC_STATUS_TIMEOUT)
-                guac_user_abort(user, GUAC_PROTOCOL_STATUS_CLIENT_TIMEOUT, "User is not responding.");
-
-            else {
-                if (guac_error != GUAC_STATUS_CLOSED)
-                    guacd_client_log_guac_error(client, GUAC_LOG_WARNING,
-                            "Guacamole connection failure");
-                guac_user_stop(user);
-            }
-
-            return NULL;
-        }
-
-        /* Reset guac_error and guac_error_message (user/client handlers are not
-         * guaranteed to set these) */
-        guac_error = GUAC_STATUS_SUCCESS;
-        guac_error_message = NULL;
-
-        /* Call handler, stop on error */
-        if (guac_user_handle_instruction(user, parser->opcode, parser->argc, parser->argv) < 0) {
-
-            /* Log error */
-            guacd_client_log_guac_error(client, GUAC_LOG_WARNING,
-                    "User connection aborted");
-
-            /* Log handler details */
-            guac_user_log(user, GUAC_LOG_DEBUG, "Failing instruction handler in user was \"%s\"", parser->opcode);
-
-            guac_user_stop(user);
-            return NULL;
-        }
-
-    }
-
-    return NULL;
-
-}
-
-int guacd_user_start(guac_parser* parser, guac_user* user) {
-
-    guacd_user_input_thread_params params = {
-        .parser = parser,
-        .user = user
-    };
-
-    pthread_t input_thread;
-
-    if (pthread_create(&input_thread, NULL, guacd_user_input_thread, (void*) &params)) {
-        guac_user_log(user, GUAC_LOG_ERROR, "Unable to start input thread");
-        guac_user_stop(user);
-        return -1;
-    }
-
-    /* Wait for I/O threads */
-    pthread_join(input_thread, NULL);
-
-    /* Explicitly signal disconnect */
-    guac_protocol_send_disconnect(user->socket);
-    guac_socket_flush(user->socket);
-
-    /* Done */
-    return 0;
-
-}
-

src/libguacd/Makefile.am

@@ -0,0 +1,50 @@
+#
+# 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.
+#
+
+AUTOMAKE_OPTIONS = foreign 
+
+noinst_LTLIBRARIES = libguacd.la
+
+noinst_HEADERS =    \
+    libguacd/log.h  \
+    libguacd/user.h
+
+libguacd_la_SOURCES = \
+    log.c             \
+    user.c
+
+libguacd_la_CFLAGS =        \
+    -Werror -Wall -pedantic \
+    @COMMON_INCLUDE@        \
+    @LIBGUAC_INCLUDE@
+
+libguacd_la_LIBADD = \
+    @COMMON_LTLIB@   \
+    @LIBGUAC_LTLIB@
+
+libguacd_la_LDFLAGS = \
+    @PTHREAD_LIBS@    \
+    @SSL_LIBS@
+
+# SSL support
+if ENABLE_SSL
+noinst_HEADERS      += libguacd/socket-ssl.h
+libguacd_la_SOURCES += socket-ssl.c
+endif
+

src/libguacd/libguacd/log.h

@@ -0,0 +1,42 @@
+/*
+ * 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 LIBGUACD_LOG_H
+#define LIBGUACD_LOG_H
+
+#include "config.h"
+
+#include <guacamole/client.h>
+
+/**
+ * Prints an error message using the logging facilities of the given client,
+ * automatically including any information present in guac_error. This function
+ * accepts parameters identically to printf.
+ */
+void guacd_client_log_guac_error(guac_client* client,
+        guac_client_log_level level, const char* message);
+
+/**
+ * Logs a reasonable explanatory message regarding handshake failure based on
+ * the current value of guac_error.
+ */
+void guacd_client_log_handshake_failure(guac_client* client);
+
+#endif
+

src/libguacd/libguacd/user.h

@@ -18,8 +18,8 @@
  */
 
 
-#ifndef _GUACD_USER_H
+#ifndef LIBGUACD_USER_H
-#define _GUACD_USER_H
+#define LIBGUACD_USER_H
 
 #include "config.h"
 
@@ -80,6 +80,21 @@ typedef struct guacd_user_input_thread_params {
  */
 int guacd_user_start(guac_parser* parser, guac_user* user);
 
+/**
+ * Handles the initial handshake of a user and all subsequent I/O. This
+ * function blocks until the user disconnects.
+ *
+ * @param user
+ *     The user whose handshake and entire Guacamole protocol exchange should
+ *     be handled.
+ *
+ * @return
+ *     Zero if the user's Guacamole connection was successfully handled and
+ *     the user has disconnected, or non-zero if an error prevented the user's
+ *     connection from being handled properly.
+ */
+int guacd_handle_user(guac_user* user);
+
 /**
  * The thread which handles all user input, calling event handlers for received
  * instructions.

src/libguacd/log.c

@@ -0,0 +1,72 @@
+/*
+ * 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 "config.h"
+#include "libguacd/log.h"
+
+#include <guacamole/client.h>
+#include <guacamole/error.h>
+
+#include <stdarg.h>
+#include <stdio.h>
+#include <syslog.h>
+#include <unistd.h>
+
+void guacd_client_log_guac_error(guac_client* client,
+        guac_client_log_level level, const char* message) {
+
+    if (guac_error != GUAC_STATUS_SUCCESS) {
+
+        /* If error message provided, include in log */
+        if (guac_error_message != NULL)
+            guac_client_log(client, level, "%s: %s",
+                    message,
+                    guac_error_message);
+
+        /* Otherwise just log with standard status string */
+        else
+            guac_client_log(client, level, "%s: %s",
+                    message,
+                    guac_status_string(guac_error));
+
+    }
+
+    /* Just log message if no status code */
+    else
+        guac_client_log(client, level, "%s", message);
+
+}
+
+void guacd_client_log_handshake_failure(guac_client* client) {
+
+    if (guac_error == GUAC_STATUS_CLOSED)
+        guac_client_log(client, GUAC_LOG_INFO,
+                "Guacamole connection closed during handshake");
+    else if (guac_error == GUAC_STATUS_PROTOCOL_ERROR)
+        guac_client_log(client, GUAC_LOG_ERROR,
+                "Guacamole protocol violation. Perhaps the version of "
+                "guacamole-client is incompatible with this version of "
+                "guacd?");
+    else
+        guac_client_log(client, GUAC_LOG_WARNING,
+                "Guacamole handshake failed: %s",
+                guac_status_string(guac_error));
+
+}
+

src/libguacd/socket-ssl.c

@@ -19,7 +19,7 @@
 
 #include "config.h"
 
-#include "socket-ssl.h"
+#include "libguacd/socket-ssl.h"
 
 #include <poll.h>
 #include <stdlib.h>

src/libguacd/user.c

@@ -0,0 +1,321 @@
+/*
+ * 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 "config.h"
+
+#include "libguacd/log.h"
+#include "libguacd/user.h"
+
+#include <guacamole/client.h>
+#include <guacamole/error.h>
+#include <guacamole/parser.h>
+#include <guacamole/protocol.h>
+#include <guacamole/socket.h>
+#include <guacamole/user.h>
+
+#include <pthread.h>
+#include <stdlib.h>
+#include <string.h>
+
+/**
+ * Copies the given array of mimetypes (strings) into a newly-allocated NULL-
+ * terminated array of strings. Both the array and the strings within the array
+ * are newly-allocated and must be later freed via guacd_free_mimetypes().
+ *
+ * @param mimetypes
+ *     The array of mimetypes to copy.
+ *
+ * @param count
+ *     The number of mimetypes in the given array.
+ *
+ * @return
+ *     A newly-allocated, NULL-terminated array containing newly-allocated
+ *     copies of each of the mimetypes provided in the original mimetypes
+ *     array.
+ */
+static char** guacd_copy_mimetypes(char** mimetypes, int count) {
+
+    int i;
+
+    /* Allocate sufficient space for NULL-terminated array of mimetypes */
+    char** mimetypes_copy = malloc(sizeof(char*) * (count+1));
+
+    /* Copy each provided mimetype */
+    for (i = 0; i < count; i++)
+        mimetypes_copy[i] = strdup(mimetypes[i]);
+
+    /* Terminate with NULL */
+    mimetypes_copy[count] = NULL;
+
+    return mimetypes_copy;
+
+}
+
+/**
+ * Frees the given array of mimetypes, including the space allocated to each
+ * mimetype string within the array. The provided array of mimetypes MUST have
+ * been allocated with guacd_copy_mimetypes().
+ *
+ * @param mimetypes
+ *     The NULL-terminated array of mimetypes to free. This array MUST have
+ *     been previously allocated with guacd_copy_mimetypes().
+ */
+static void guacd_free_mimetypes(char** mimetypes) {
+
+    char** current_mimetype = mimetypes;
+
+    /* Free all strings within NULL-terminated mimetype array */
+    while (*current_mimetype != NULL) {
+        free(*current_mimetype);
+        current_mimetype++;
+    }
+
+    /* Free the array itself, now that its contents have been freed */
+    free(mimetypes);
+
+}
+
+void* guacd_user_input_thread(void* data) {
+
+    guacd_user_input_thread_params* params = (guacd_user_input_thread_params*) data;
+    guac_user* user = params->user;
+    guac_parser* parser = params->parser;
+    guac_client* client = user->client;
+    guac_socket* socket = user->socket;
+
+    /* Guacamole user input loop */
+    while (client->state == GUAC_CLIENT_RUNNING && user->active) {
+
+        /* Read instruction, stop on error */
+        if (guac_parser_read(parser, socket, GUACD_USEC_TIMEOUT)) {
+
+            if (guac_error == GUAC_STATUS_TIMEOUT)
+                guac_user_abort(user, GUAC_PROTOCOL_STATUS_CLIENT_TIMEOUT, "User is not responding.");
+
+            else {
+                if (guac_error != GUAC_STATUS_CLOSED)
+                    guacd_client_log_guac_error(client, GUAC_LOG_WARNING,
+                            "Guacamole connection failure");
+                guac_user_stop(user);
+            }
+
+            return NULL;
+        }
+
+        /* Reset guac_error and guac_error_message (user/client handlers are not
+         * guaranteed to set these) */
+        guac_error = GUAC_STATUS_SUCCESS;
+        guac_error_message = NULL;
+
+        /* Call handler, stop on error */
+        if (guac_user_handle_instruction(user, parser->opcode, parser->argc, parser->argv) < 0) {
+
+            /* Log error */
+            guacd_client_log_guac_error(client, GUAC_LOG_WARNING,
+                    "User connection aborted");
+
+            /* Log handler details */
+            guac_user_log(user, GUAC_LOG_DEBUG, "Failing instruction handler in user was \"%s\"", parser->opcode);
+
+            guac_user_stop(user);
+            return NULL;
+        }
+
+    }
+
+    return NULL;
+
+}
+
+int guacd_user_start(guac_parser* parser, guac_user* user) {
+
+    guacd_user_input_thread_params params = {
+        .parser = parser,
+        .user = user
+    };
+
+    pthread_t input_thread;
+
+    if (pthread_create(&input_thread, NULL, guacd_user_input_thread, (void*) &params)) {
+        guac_user_log(user, GUAC_LOG_ERROR, "Unable to start input thread");
+        guac_user_stop(user);
+        return -1;
+    }
+
+    /* Wait for I/O threads */
+    pthread_join(input_thread, NULL);
+
+    /* Explicitly signal disconnect */
+    guac_protocol_send_disconnect(user->socket);
+    guac_socket_flush(user->socket);
+
+    /* Done */
+    return 0;
+
+}
+
+int guacd_handle_user(guac_user* user) {
+
+    guac_socket* socket = user->socket;
+    guac_client* client = user->client;
+
+    /* Send args */
+    if (guac_protocol_send_args(socket, client->args)
+            || guac_socket_flush(socket)) {
+
+        /* Log error */
+        guacd_client_log_handshake_failure(client);
+        guacd_client_log_guac_error(client, GUAC_LOG_DEBUG,
+                "Error sending \"args\" to new user");
+
+        return 1;
+    }
+
+    guac_parser* parser = guac_parser_alloc();
+
+    /* Get optimal screen size */
+    if (guac_parser_expect(parser, socket, GUACD_USEC_TIMEOUT, "size")) {
+
+        /* Log error */
+        guacd_client_log_handshake_failure(client);
+        guacd_client_log_guac_error(client, GUAC_LOG_DEBUG,
+                "Error reading \"size\"");
+
+        guac_parser_free(parser);
+        return 1;
+    }
+
+    /* Validate content of size instruction */
+    if (parser->argc < 2) {
+        guac_client_log(client, GUAC_LOG_ERROR, "Received \"size\" "
+                "instruction lacked required arguments.");
+        guac_parser_free(parser);
+        return 1;
+    }
+
+    /* Parse optimal screen dimensions from size instruction */
+    user->info.optimal_width  = atoi(parser->argv[0]);
+    user->info.optimal_height = atoi(parser->argv[1]);
+
+    /* If DPI given, set the client resolution */
+    if (parser->argc >= 3)
+        user->info.optimal_resolution = atoi(parser->argv[2]);
+
+    /* Otherwise, use a safe default for rough backwards compatibility */
+    else
+        user->info.optimal_resolution = 96;
+
+    /* Get supported audio formats */
+    if (guac_parser_expect(parser, socket, GUACD_USEC_TIMEOUT, "audio")) {
+
+        /* Log error */
+        guacd_client_log_handshake_failure(client);
+        guacd_client_log_guac_error(client, GUAC_LOG_DEBUG,
+                "Error reading \"audio\"");
+
+        guac_parser_free(parser);
+        return 1;
+    }
+
+    /* Store audio mimetypes */
+    char** audio_mimetypes = guacd_copy_mimetypes(parser->argv, parser->argc);
+    user->info.audio_mimetypes = (const char**) audio_mimetypes;
+
+    /* Get supported video formats */
+    if (guac_parser_expect(parser, socket, GUACD_USEC_TIMEOUT, "video")) {
+
+        /* Log error */
+        guacd_client_log_handshake_failure(client);
+        guacd_client_log_guac_error(client, GUAC_LOG_DEBUG,
+                "Error reading \"video\"");
+
+        guac_parser_free(parser);
+        return 1;
+    }
+
+    /* Store video mimetypes */
+    char** video_mimetypes = guacd_copy_mimetypes(parser->argv, parser->argc);
+    user->info.video_mimetypes = (const char**) video_mimetypes;
+
+    /* Get supported image formats */
+    if (guac_parser_expect(parser, socket, GUACD_USEC_TIMEOUT, "image")) {
+
+        /* Log error */
+        guacd_client_log_handshake_failure(client);
+        guacd_client_log_guac_error(client, GUAC_LOG_DEBUG,
+                "Error reading \"image\"");
+
+        guac_parser_free(parser);
+        return 1;
+    }
+
+    /* Store image mimetypes */
+    char** image_mimetypes = guacd_copy_mimetypes(parser->argv, parser->argc);
+    user->info.image_mimetypes = (const char**) image_mimetypes;
+
+    /* Get args from connect instruction */
+    if (guac_parser_expect(parser, socket, GUACD_USEC_TIMEOUT, "connect")) {
+
+        /* Log error */
+        guacd_client_log_handshake_failure(client);
+        guacd_client_log_guac_error(client, GUAC_LOG_DEBUG,
+                "Error reading \"connect\"");
+
+        guac_parser_free(parser);
+        return 1;
+    }
+
+    /* Acknowledge connection availability */
+    guac_protocol_send_ready(socket, client->connection_id);
+    guac_socket_flush(socket);
+
+    /* Attempt join */
+    if (guac_client_add_user(client, user, parser->argc, parser->argv))
+        guac_client_log(client, GUAC_LOG_ERROR, "User \"%s\" could NOT "
+                "join connection \"%s\"", user->user_id, client->connection_id);
+
+    /* Begin user connection if join successful */
+    else {
+
+        guac_client_log(client, GUAC_LOG_INFO, "User \"%s\" joined connection "
+                "\"%s\" (%i users now present)", user->user_id,
+                client->connection_id, client->connected_users);
+
+        /* Handle user I/O, wait for connection to terminate */
+        guacd_user_start(parser, user);
+
+        /* Remove/free user */
+        guac_client_remove_user(client, user);
+        guac_client_log(client, GUAC_LOG_INFO, "User \"%s\" disconnected (%i "
+                "users remain)", user->user_id, client->connected_users);
+
+    }
+
+    /* Free mimetype lists */
+    guacd_free_mimetypes(audio_mimetypes);
+    guacd_free_mimetypes(video_mimetypes);
+    guacd_free_mimetypes(image_mimetypes);
+
+    guac_parser_free(parser);
+
+    /* Successful disconnect */
+    return 0;
+
+}
+