diff --git a/src/Makefile.am b/src/Makefile.am
index 0f677d26..e7ea542e 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -7,7 +7,7 @@ SUBDIRS = common/avl common/net common/thread common/httpp common/log common/tim
 bin_PROGRAMS = icecast
 
 noinst_HEADERS = admin.h cfgfile.h logging.h sighandler.h connection.h \
-    global.h util.h curl.h slave.h source.h stats.h refbuf.h client.h playlist.h \
+    global.h util.h errors.h curl.h slave.h source.h stats.h refbuf.h client.h playlist.h \
     compat.h fserve.h xslt.h yp.h md5.h matchfile.h tls.h \
     event.h event_log.h event_exec.h event_url.h \
     acl.h auth.h \
@@ -15,7 +15,7 @@ noinst_HEADERS = admin.h cfgfile.h logging.h sighandler.h connection.h \
     format_vorbis.h format_theora.h format_flac.h format_speex.h format_midi.h \
     format_kate.h format_skeleton.h format_opus.h
 icecast_SOURCES = cfgfile.c main.c logging.c sighandler.c connection.c global.c \
-    util.c slave.c source.c stats.c refbuf.c client.c playlist.c \
+    util.c errors.c slave.c source.c stats.c refbuf.c client.c playlist.c \
     xslt.c fserve.c admin.c md5.c matchfile.c tls.c \
     format.c format_ogg.c format_mp3.c format_midi.c format_flac.c format_ebml.c \
     format_kate.c format_skeleton.c format_opus.c \
diff --git a/src/admin.c b/src/admin.c
index a1ea26cd..135a39ea 100644
--- a/src/admin.c
+++ b/src/admin.c
@@ -8,7 +8,7 @@
  *                      oddsock <oddsock@xiph.org>,
  *                      Karl Heyes <karl@xiph.org>
  *                      and others (see AUTHORS for details).
- * Copyright 2012-2014, Philipp "ph3-der-loewe" Schafft <lion@lion.leolix.org>,
+ * Copyright 2012-2018, Philipp "ph3-der-loewe" Schafft <lion@lion.leolix.org>,
  */
 
 #ifdef HAVE_CONFIG_H
@@ -34,6 +34,7 @@
 #include "xslt.h"
 #include "fserve.h"
 #include "admin.h"
+#include "errors.h"
 
 #include "format.h"
 
@@ -50,7 +51,7 @@
     do {                                                                \
         (var) = httpp_get_query_param((client)->parser, (name));        \
         if((var) == NULL) {                                             \
-            client_send_error((client), 400, 0, "Missing parameter");   \
+            client_send_error_by_id(client, ICECAST_ERROR_ADMIN_MISSING_PARAMETER); \
             return;                                                     \
         }                                                               \
     } while(0);
@@ -283,7 +284,7 @@ void admin_send_response(xmlDocPtr     doc,
                                      NULL, NULL, client);
         if (ret < 0) {
             ICECAST_LOG_ERROR("Dropping client as we can not build response headers.");
-            client_send_error(client, 500, 0, "Header generation failed.");
+            client_send_error_by_id(client, ICECAST_ERROR_GEN_HEADER_GEN_FAILED);
             xmlFree(buff);
             return;
         } else if (buf_len < (size_t)(len + ret + 64)) {
@@ -300,13 +301,13 @@ void admin_send_response(xmlDocPtr     doc,
                                              NULL, NULL, client);
                 if (ret == -1) {
                     ICECAST_LOG_ERROR("Dropping client as we can not build response headers.");
-                    client_send_error(client, 500, 0, "Header generation failed.");
+                    client_send_error_by_id(client, ICECAST_ERROR_GEN_HEADER_GEN_FAILED);
                     xmlFree(buff);
                     return;
                 }
             } else {
                 ICECAST_LOG_ERROR("Client buffer reallocation failed. Dropping client.");
-                client_send_error(client, 500, 0, "Buffer reallocation failed.");
+                client_send_error_by_id(client, ICECAST_ERROR_GEN_BUFFER_REALLOC);
                 xmlFree(buff);
                 return;
             }
@@ -352,7 +353,7 @@ void admin_handle_request(client_t *client, const char *uri)
     if (handler == NULL) {
         ICECAST_LOG_ERROR("Error parsing command string or unrecognised command: %H",
                 uri);
-        client_send_error(client, 400, 0, "Unrecognised command");
+        client_send_error_by_id(client, ICECAST_ERROR_ADMIN_UNRECOGNISED_COMMAND);
         return;
     }
 
@@ -366,7 +367,7 @@ void admin_handle_request(client_t *client, const char *uri)
             ICECAST_LOG_DEBUG("Granted right to call COMMAND_RAW_METADATA_UPDATE to "
                 "client because it is allowed to do SOURCE or PUT.");
         } else {
-            client_send_error(client, 401, 1, "You need to authenticate\r\n");
+            client_send_error_by_id(client, ICECAST_ERROR_GEN_CLIENT_NEEDS_TO_AUTHENTICATE);
             return;
         }
     }
@@ -385,14 +386,14 @@ void admin_handle_request(client_t *client, const char *uri)
             avl_tree_unlock(global.source_tree);
             ICECAST_LOG_WARN("Admin command \"%H\" on non-existent source \"%H\"",
                     uri, mount);
-            client_send_error(client, 400, 0, "Source does not exist");
+            client_send_error_by_id(client, ICECAST_ERROR_ADMIN_SOURCE_DOES_NOT_EXIST);
             return;
         } /* No Source running */
         else if (source->running == 0 && source->on_demand == 0) {
             avl_tree_unlock(global.source_tree);
             ICECAST_LOG_INFO("Received admin command \"%H\" on unavailable mount \"%H\"",
                     uri, mount);
-            client_send_error(client, 400, 0, "Source is not available");
+            client_send_error_by_id(client, ICECAST_ERROR_ADMIN_SOURCE_IS_NOT_AVAILABLE);
             return;
         }
         ICECAST_LOG_INFO("Received admin command %H on mount '%s'",
@@ -400,7 +401,7 @@ void admin_handle_request(client_t *client, const char *uri)
     }
 
     if (handler->type == ADMINTYPE_MOUNT && !source) {
-        client_send_error(client, 400, 0, "Mount parameter mandatory");
+        client_send_error_by_id(client, ICECAST_ERROR_ADMIN_MISSING_PARAMETER);
         return;
     }
 
@@ -422,7 +423,7 @@ static void html_success(client_t *client, char *message)
 
     if (ret == -1 || ret >= PER_CLIENT_REFBUF_SIZE) {
         ICECAST_LOG_ERROR("Dropping client as we can not build response headers.");
-        client_send_error(client, 500, 0, "Header generation failed.");
+        client_send_error_by_id(client, ICECAST_ERROR_GEN_HEADER_GEN_FAILED);
         return;
     }
 
@@ -463,17 +464,17 @@ static void command_move_clients(client_t   *client,
     dest = source_find_mount(dest_source);
 
     if (dest == NULL) {
-        client_send_error(client, 400, 0, "No such destination");
+        client_send_error_by_id(client, ICECAST_ERROR_ADMIN_NO_SUCH_DESTINATION);
         return;
     }
 
     if (strcmp(dest->mount, source->mount) == 0) {
-        client_send_error(client, 400, 0, "supplied mountpoints are identical");
+        client_send_error_by_id(client, ICECAST_ERROR_ADMIN_SUPPLIED_MOUNTPOINTS_ARE_IDENTICAL);
         return;
     }
 
     if (dest->running == 0 && dest->on_demand == 0) {
-        client_send_error(client, 400, 0, "Destination not running");
+        client_send_error_by_id(client, ICECAST_ERROR_ADMIN_DEST_NOT_RUNNING);
         return;
     }
 
@@ -611,7 +612,7 @@ static void command_buildm3u(client_t *client, source_t *source, int format)
     if (ret == -1 || ret >= (PER_CLIENT_REFBUF_SIZE - 512)) {
         /* we want at least 512 Byte left for data */
         ICECAST_LOG_ERROR("Dropping client as we can not build response headers.");
-        client_send_error(client, 500, 0, "Header generation failed.");
+        client_send_error_by_id(client, ICECAST_ERROR_GEN_HEADER_GEN_FAILED);
         return;
     }
 
@@ -664,8 +665,7 @@ static void command_manageauth(client_t *client, source_t *source, int response)
     const char *idstring = NULL;
     char *message = NULL;
     int ret = AUTH_OK;
-    int error_code = 400;
-    const char *error_message = "missing parameter";
+    int error_id = ICECAST_ERROR_ADMIN_missing_parameter;
     long unsigned int id;
     ice_config_t *config = config_get_config();
     auth_t *auth;
@@ -692,8 +692,7 @@ static void command_manageauth(client_t *client, source_t *source, int response)
         /* check if we found one */
         if (auth == NULL) {
             ICECAST_LOG_WARN("Client requested mangement for unknown role %lu", id);
-            error_code = 404;
-            error_message = "Role not found";
+            error_id = ICECAST_ERROR_ADMIN_ROLEMGN_ROLE_NOT_FOUND;
             break;
         }
 
@@ -713,7 +712,7 @@ static void command_manageauth(client_t *client, source_t *source, int response)
             }
 
             if (!auth->adduser) {
-                error_message = "Adding users to role not supported by role";
+                error_id = ICECAST_ERROR_ADMIN_ROLEMGN_ADD_NOSYS;
                 break;
             }
 
@@ -733,7 +732,7 @@ static void command_manageauth(client_t *client, source_t *source, int response)
             }
 
             if (!auth->deleteuser) {
-                error_message = "Deleting users from role not supported by role";
+                error_id = ICECAST_ERROR_ADMIN_ROLEMGN_DELETE_NOSYS;
                 break;
             }
 
@@ -774,7 +773,7 @@ static void command_manageauth(client_t *client, source_t *source, int response)
 
     config_release_config();
     auth_release(auth);
-    client_send_error(client, error_code, 0, error_message);
+    client_send_error_by_id(client, error_id);
 }
 
 static void command_kill_source(client_t *client,
@@ -944,7 +943,7 @@ static void command_shoutcast_metadata(client_t *client,
     if (source->shoutcast_compat == 0) {
         ICECAST_LOG_ERROR("illegal change of metadata on non-shoutcast "
                         "compatible stream");
-        client_send_error(client, 400, 0, "illegal metadata call");
+        client_send_error_by_id(client, ICECAST_ERROR_ADMIN_METADAT_BADCALL);
         return;
     }
 
@@ -957,7 +956,7 @@ static void command_shoutcast_metadata(client_t *client,
     COMMAND_REQUIRE(client, "song", value);
 
     if (strcmp (action, "updinfo") != 0) {
-        client_send_error(client, 400, 0, "No such action");
+        client_send_error_by_id(client, ICECAST_ERROR_ADMIN_METADAT_NO_SUCH_ACTION);
         return;
     }
     if (source->client && strcmp (client->con->ip, source->client->con->ip) != 0)
@@ -972,7 +971,7 @@ static void command_shoutcast_metadata(client_t *client,
                 source->mount, value);
         html_success(client, "Metadata update successful");
     } else {
-        client_send_error(client, 400, 0, "mountpoint will not accept URL updates");
+        client_send_error_by_id(client, ICECAST_ERROR_ADMIN_MOUNT_NOT_ACCEPT_URL_UPDATES);
     }
 }
 
@@ -1022,7 +1021,7 @@ static void command_list_mounts(client_t *client, source_t *source, int response
 
         if (ret == -1 || ret >= PER_CLIENT_REFBUF_SIZE) {
             ICECAST_LOG_ERROR("Dropping client as we can not build response headers.");
-            client_send_error(client, 500, 0, "Header generation failed.");
+            client_send_error_by_id(client, ICECAST_ERROR_GEN_HEADER_GEN_FAILED);
             return;
         }
 
diff --git a/src/auth.c b/src/auth.c
index 47427560..fbff604a 100644
--- a/src/auth.c
+++ b/src/auth.c
@@ -8,7 +8,7 @@
  *                      oddsock <oddsock@xiph.org>,
  *                      Karl Heyes <karl@xiph.org>
  *                      and others (see AUTHORS for details).
- * Copyright 2013-2014, Philipp "ph3-der-loewe" Schafft <lion@lion.leolix.org>,
+ * Copyright 2013-2018, Philipp "ph3-der-loewe" Schafft <lion@lion.leolix.org>,
  */
 
 /**
@@ -27,6 +27,7 @@
 #include "auth.h"
 #include "source.h"
 #include "client.h"
+#include "errors.h"
 #include "cfgfile.h"
 #include "stats.h"
 #include "common/httpp/httpp.h"
@@ -373,7 +374,7 @@ static void auth_add_client(auth_t *auth, client_t *client, void (*on_no_match)(
     /* TODO: replace that magic number */
     if (auth->pending_count > 100) {
         ICECAST_LOG_WARN("too many clients awaiting authentication on auth %p", auth);
-        client_send_error(client, 403, 1, "busy, please try again later");
+        client_send_error_by_id(client, ICECAST_ERROR_AUTH_BUSY);
         return;
     }
 
diff --git a/src/client.c b/src/client.c
index da95c589..18e8deb1 100644
--- a/src/client.c
+++ b/src/client.c
@@ -8,7 +8,7 @@
  *                      oddsock <oddsock@xiph.org>,
  *                      Karl Heyes <karl@xiph.org>
  *                      and others (see AUTHORS for details).
- * Copyright 2011-2014, Philipp "ph3-der-loewe" Schafft <lion@lion.leolix.org>,
+ * Copyright 2011-2018, Philipp "ph3-der-loewe" Schafft <lion@lion.leolix.org>,
  */
 
 /* client.c
@@ -34,6 +34,7 @@
 #include "format.h"
 #include "stats.h"
 #include "fserve.h"
+#include "errors.h"
 
 #include "client.h"
 #include "auth.h"
@@ -214,7 +215,7 @@ int client_read_bytes(client_t *client, void *buf, unsigned len)
     return bytes;
 }
 
-void client_send_error(client_t *client, int status, int plain, const char *message)
+static inline void _client_send_error(client_t *client, int status, int plain, const char *message)
 {
     ssize_t ret;
     refbuf_t *data;
@@ -264,6 +265,30 @@ void client_send_error(client_t *client, int status, int plain, const char *mess
     fserve_add_client (client, NULL);
 }
 
+void client_send_error_by_id(client_t *client, int id)
+{
+    const icecast_error_t *error = error_get_by_id(id);
+    const char *pref;
+    int plain;
+
+    if (!error) {
+         client_send_500(client, "Unknown error ID");
+         return;
+    }
+
+    pref = util_http_select_best(httpp_getvar(client->parser, "accept"), "text/plain", "text/html", (const char*)NULL);
+
+    if (strcmp(pref, "text/plain") == 0) {
+        plain = 1;
+    } else if (strcmp(pref, "text/html") == 0) {
+        plain = 0;
+    } else {
+        plain = 1;
+    }
+
+    _client_send_error(client, error->http_status, plain, error->message);
+}
+
 void client_send_101(client_t *client, reuse_t reuse)
 {
     ssize_t ret;
diff --git a/src/client.h b/src/client.h
index 2f2a3259..2cdc67f9 100644
--- a/src/client.h
+++ b/src/client.h
@@ -8,7 +8,7 @@
  *                      oddsock <oddsock@xiph.org>,
  *                      Karl Heyes <karl@xiph.org>
  *                      and others (see AUTHORS for details).
- * Copyright 2011-2014, Philipp "ph3-der-loewe" Schafft <lion@lion.leolix.org>,
+ * Copyright 2011-2018, Philipp "ph3-der-loewe" Schafft <lion@lion.leolix.org>,
  */
 
 /* client.h
@@ -109,7 +109,7 @@ typedef struct _client_tag
 
 int client_create (client_t **c_ptr, connection_t *con, http_parser_t *parser);
 void client_destroy(client_t *client);
-void client_send_error(client_t *client, int status, int plain, const char *message);
+void client_send_error_by_id(client_t *client, int id);
 void client_send_101(client_t *client, reuse_t reuse);
 void client_send_426(client_t *client, reuse_t reuse);
 int client_send_bytes (client_t *client, const void *buf, unsigned len);
diff --git a/src/connection.c b/src/connection.c
index 98a96b72..8568cc26 100644
--- a/src/connection.c
+++ b/src/connection.c
@@ -9,7 +9,7 @@
  *                      Karl Heyes <karl@xiph.org>
  *                      and others (see AUTHORS for details).
  * Copyright 2011,      Dave 'justdave' Miller <justdave@mozilla.com>,
- * Copyright 2011-2014, Philipp "ph3-der-loewe" Schafft <lion@lion.leolix.org>,
+ * Copyright 2011-2018, Philipp "ph3-der-loewe" Schafft <lion@lion.leolix.org>,
  */
 
 /* -*- c-basic-offset: 4; indent-tabs-mode: nil; -*- */
@@ -46,6 +46,7 @@
 #include "connection.h"
 #include "refbuf.h"
 #include "client.h"
+#include "errors.h"
 #include "stats.h"
 #include "logging.h"
 #include "xslt.h"
@@ -575,7 +576,7 @@ void connection_queue(connection_t *con)
     global_lock();
     if (client_create(&client, con, NULL) < 0) {
         global_unlock();
-        client_send_error(client, 403, 1, "Icecast connection limit reached");
+        client_send_error_by_id(client, ICECAST_ERROR_GEN_CLIENT_LIMIT);
         /* don't be too eager as this is an imposed hard limit */
         thread_sleep(400000);
         return;
@@ -659,7 +660,7 @@ int connection_complete_source(source_t *source, int response)
                 config_release_config();
                 global_unlock();
                 if (response) {
-                    client_send_error(source->client, 403, 1, "Content-type not supported");
+                    client_send_error_by_id(source->client, ICECAST_ERROR_CON_CONTENT_TYPE_NOSYS);
                     source->client = NULL;
                 }
                 ICECAST_LOG_WARN("Content-type \"%s\" not supported, dropping source", contenttype);
@@ -669,7 +670,7 @@ int connection_complete_source(source_t *source, int response)
             config_release_config();
             global_unlock();
             if (response) {
-                client_send_error(source->client, 403, 1, "No Content-type given");
+                client_send_error_by_id(source->client, ICECAST_ERROR_CON_NO_CONTENT_TYPE_GIVEN);
                 source->client = NULL;
             }
             ICECAST_LOG_ERROR("Content-type not given in PUT request, dropping source");
@@ -685,7 +686,7 @@ int connection_complete_source(source_t *source, int response)
             global_unlock();
             config_release_config();
             if (response) {
-                client_send_error(source->client, 403, 1, "internal format allocation problem");
+                client_send_error_by_id(source->client, ICECAST_ERROR_CON_INTERNAL_FORMAT_ALLOC_ERROR);
                 source->client = NULL;
             }
             ICECAST_LOG_WARN("plugin format failed for \"%s\"", source->mount);
@@ -714,7 +715,7 @@ int connection_complete_source(source_t *source, int response)
     config_release_config();
 
     if (response) {
-        client_send_error(source->client, 403, 1, "too many sources connected");
+        client_send_error_by_id(source->client, ICECAST_ERROR_CON_SOURCE_CLIENT_LIMIT);
         source->client = NULL;
     }
 
@@ -754,7 +755,7 @@ static inline void source_startup(client_t *client, const char *uri)
             if (transfer_encoding && strcasecmp(transfer_encoding, HTTPP_ENCODING_IDENTITY) != 0) {
                 client->encoding = httpp_encoding_new(transfer_encoding);
                 if (!client->encoding) {
-                    client_send_error(client, 501, 1, "Unimplemented");
+                    client_send_error_by_id(client, ICECAST_ERROR_CON_UNIMPLEMENTED);
                     return;
                 }
             }
@@ -784,7 +785,7 @@ static inline void source_startup(client_t *client, const char *uri)
             fserve_add_client_callback(client, source_client_callback, source);
         }
     } else {
-        client_send_error(client, 403, 1, "Mountpoint in use");
+        client_send_error_by_id(client, ICECAST_ERROR_CON_MOUNT_IN_USE);
         ICECAST_LOG_WARN("Mountpoint %s in use", uri);
     }
 }
@@ -797,7 +798,7 @@ static void _handle_source_request(client_t *client, const char *uri)
 
     if (uri[0] != '/') {
         ICECAST_LOG_WARN("source mountpoint not starting with /");
-        client_send_error(client, 400, 1, "source mountpoint not starting with /");
+        client_send_error_by_id(client, ICECAST_ERROR_CON_MOUNTPOINT_NOT_STARTING_WITH_SLASH);
         return;
     }
 
@@ -932,7 +933,7 @@ static void _handle_get_request(client_t *client, char *uri) {
         if (client->protocol == ICECAST_PROTOCOL_SHOUTCAST) {
             client_destroy(client);
         } else {
-            client_send_error(client, 401, 1, "You need to authenticate\r\n");
+            client_send_error_by_id(client, ICECAST_ERROR_GEN_CLIENT_NEEDS_TO_AUTHENTICATE);
         }
         return;
     }
@@ -954,8 +955,7 @@ static void _handle_get_request(client_t *client, char *uri) {
         /* check for duplicate_logins */
         if (max_connections_per_user > 0) { /* -1 = not set (-> default=unlimited), 0 = unlimited */
             if (max_connections_per_user <= __count_user_role_on_mount(source, client)) {
-                client_send_error(client, 403, 1, "Reached limit of concurrent "
-                    "connections on those credentials");
+                client_send_error_by_id(client, ICECAST_ERROR_CON_PER_CRED_CLIENT_LIMIT);
                 in_error = 1;
             }
         }
@@ -976,7 +976,7 @@ static void _handle_get_request(client_t *client, char *uri) {
                 client->con->discon_time = connection_duration + time(NULL);
         }
         if (!in_error && __add_listener_to_source(source, client) == -1) {
-            client_send_error(client, 403, 1, "Rejecting client for whatever reason");
+            client_send_error_by_id(client, ICECAST_ERROR_CON_rejecting_client_for_whatever_reason);
         }
         avl_tree_unlock(global.source_tree);
     } else {
@@ -1143,14 +1143,14 @@ static void _handle_authed_client(client_t *client, void *uri, auth_result resul
     client->authstack = NULL;
 
     if (result != AUTH_OK) {
-        client_send_error(client, 401, 1, "You need to authenticate\r\n");
+        client_send_error_by_id(client, ICECAST_ERROR_GEN_CLIENT_NEEDS_TO_AUTHENTICATE);
         free(uri);
         return;
     }
 
     if (acl_test_method(client->acl, client->parser->req_type) != ACL_POLICY_ALLOW) {
         ICECAST_LOG_ERROR("Client (role=%s, username=%s) not allowed to use this request method on %H", client->role, client->username, uri);
-        client_send_error(client, 401, 1, "You need to authenticate\r\n");
+        client_send_error_by_id(client, ICECAST_ERROR_GEN_CLIENT_NEEDS_TO_AUTHENTICATE);
         free(uri);
         return;
     }
@@ -1168,7 +1168,7 @@ static void _handle_authed_client(client_t *client, void *uri, auth_result resul
         break;
         default:
             ICECAST_LOG_ERROR("Wrong request type from client");
-            client_send_error(client, 400, 0, "unknown request");
+            client_send_error_by_id(client, ICECAST_ERROR_CON_UNKNOWN_REQUEST);
         break;
     }
 
@@ -1357,7 +1357,7 @@ static void _handle_connection(void)
                 connection = httpp_getvar(parser, "connection");
                 if (upgrade && connection && strcasecmp(connection, "upgrade") == 0) {
                     if (client->con->tlsmode == ICECAST_TLSMODE_DISABLED || strstr(upgrade, "TLS/1.0") == NULL) {
-                        client_send_error(client, 400, 1, "Can not upgrade protocol");
+                        client_send_error_by_id(client, ICECAST_ERROR_CON_UPGRADE_ERROR);
                         continue;
                     } else {
                         client_send_101(client, ICECAST_REUSE_UPGRADETLS);
@@ -1386,7 +1386,7 @@ static void _handle_connection(void)
                     client->admin_command = admin_get_command(uri + 1);
                     __prepare_shoutcast_admin_cgi_request(client);
                     if (!client->password) {
-                        client_send_error(client, 400, 0, "missing pass parameter");
+                        client_send_error_by_id(client, ICECAST_ERROR_CON_MISSING_PASS_PARAMETER);
                         continue;
                     }
                 } else if (strncmp("/admin/", uri, 7) == 0) {
diff --git a/src/errors.c b/src/errors.c
new file mode 100644
index 00000000..1a86973e
--- /dev/null
+++ b/src/errors.c
@@ -0,0 +1,110 @@
+/* Icecast
+ *
+ * This program is distributed under the GNU General Public License, version 2.
+ * A copy of this license is included with this source.
+ *
+ * Copyright 2018,      Philipp "ph3-der-loewe" Schafft <lion@lion.leolix.org>
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include "errors.h"
+#include "logging.h"
+#define CATMODULE "errors"
+
+// cut -d' ' -f2 x | while read x; do printf "    {.id = %-60s .http_status = xxx,\n     .message = \"\"},\n" "$x",; done
+const icecast_error_t __errors[] = {
+    {.id = ICECAST_ERROR_ADMIN_DEST_NOT_RUNNING,                        .http_status = 400,
+     .message = "Destination not running"},
+    {.id = ICECAST_ERROR_ADMIN_METADAT_BADCALL,                         .http_status = 400,
+     .message = "illegal metadata call"},
+    {.id = ICECAST_ERROR_ADMIN_METADAT_NO_SUCH_ACTION,                  .http_status = 501,
+     .message = "No such action"},
+    {.id = ICECAST_ERROR_ADMIN_MISSING_PARAMETER,                       .http_status = 400,
+     .message = "Missing parameter"},
+    {.id = ICECAST_ERROR_ADMIN_missing_parameter,                       .http_status = 400,
+     .message = "missing parameter"},
+    {.id = ICECAST_ERROR_ADMIN_MOUNT_NOT_ACCEPT_URL_UPDATES,            .http_status = 501,
+     .message = "mountpoint will not accept URL updates"},
+    {.id = ICECAST_ERROR_ADMIN_NO_SUCH_DESTINATION,                     .http_status = 404,
+     .message = "No such destination"},
+    {.id = ICECAST_ERROR_ADMIN_ROLEMGN_ADD_NOSYS,                       .http_status = 501,
+     .message = "Adding users to role not supported by role"},
+    {.id = ICECAST_ERROR_ADMIN_ROLEMGN_DELETE_NOSYS,                    .http_status = 501,
+     .message = "Deleting users from role not supported by role"},
+    {.id = ICECAST_ERROR_ADMIN_ROLEMGN_ROLE_NOT_FOUND,                  .http_status = 404,
+     .message = "Role not found"},
+    {.id = ICECAST_ERROR_ADMIN_SOURCE_DOES_NOT_EXIST,                   .http_status = 404,
+     .message = "Source does not exist"},
+    {.id = ICECAST_ERROR_ADMIN_SOURCE_IS_NOT_AVAILABLE,                 .http_status = 400,
+     .message = "Source is not available"},
+    {.id = ICECAST_ERROR_ADMIN_SUPPLIED_MOUNTPOINTS_ARE_IDENTICAL,      .http_status = 400,
+     .message = "supplied mountpoints are identical"},
+    {.id = ICECAST_ERROR_ADMIN_UNRECOGNISED_COMMAND,                    .http_status = 400,
+     .message = "unrecognised command"},
+    {.id = ICECAST_ERROR_AUTH_BUSY,                                     .http_status = 503,
+     .message = "busy, please try again later"},
+    {.id = ICECAST_ERROR_CON_CONTENT_TYPE_NOSYS,                        .http_status = 415,
+     .message = "Content-type not supported"},
+    {.id = ICECAST_ERROR_CON_INTERNAL_FORMAT_ALLOC_ERROR,               .http_status = 500,
+     .message = "internal format allocation problem"},
+    {.id = ICECAST_ERROR_CON_MISSING_PASS_PARAMETER,                    .http_status = 400 /* XXX */,
+     .message = "missing pass parameter"},
+    {.id = ICECAST_ERROR_CON_MOUNT_IN_USE,                              .http_status = 409,
+     .message = "Mountpoint in use"},
+    {.id = ICECAST_ERROR_CON_MOUNTPOINT_NOT_STARTING_WITH_SLASH,        .http_status = 400,
+     .message = "source mountpoint not starting with /"},
+    {.id = ICECAST_ERROR_CON_NO_CONTENT_TYPE_GIVEN,                     .http_status = 400,
+     .message = "No Content-type given"},
+    {.id = ICECAST_ERROR_CON_PER_CRED_CLIENT_LIMIT,                     .http_status = 429,
+     .message = "Reached limit of concurrent connections on those credentials"},
+    {.id = ICECAST_ERROR_CON_rejecting_client_for_whatever_reason,      .http_status = 403 /* XXX */,
+     .message = "Rejecting client for whatever reason"},
+    {.id = ICECAST_ERROR_CON_SOURCE_CLIENT_LIMIT,                       .http_status = 503,
+     .message = "too many sources connected"},
+    {.id = ICECAST_ERROR_CON_UNIMPLEMENTED,                             .http_status = 501,
+     .message = "Unimplemented"},
+    {.id = ICECAST_ERROR_CON_UNKNOWN_REQUEST,                           .http_status = 405,
+     .message = "unknown request"},
+    {.id = ICECAST_ERROR_CON_UPGRADE_ERROR,                             .http_status = 400 /* XXX */,
+     .message = "Can not upgrade protocol"},
+    {.id = ICECAST_ERROR_FSERV_FILE_NOT_FOUND,                          .http_status = 404,
+     .message = "The file you requested could not be found"},
+    {.id = ICECAST_ERROR_FSERV_FILE_NOT_READABLE,                       .http_status = 404 /* XXX */,
+     .message = "File not readable"},
+    {.id = ICECAST_ERROR_FSERV_REQUEST_RANGE_NOT_SATISFIABLE,           .http_status = 416,
+     .message = "Request Range Not Satisfiable"},
+    {.id = ICECAST_ERROR_GEN_BUFFER_REALLOC,                            .http_status = 500,
+     .message = "Buffer reallocation failed."},
+    {.id = ICECAST_ERROR_GEN_CLIENT_LIMIT,                              .http_status = 503,
+     .message = "Icecast connection limit reached"},
+    {.id = ICECAST_ERROR_GEN_CLIENT_NEEDS_TO_AUTHENTICATE,              .http_status = 401,
+     .message = "You need to authenticate"},
+    {.id = ICECAST_ERROR_GEN_HEADER_GEN_FAILED,                         .http_status = 500,
+     .message = "Header generation failed."},
+    {.id = ICECAST_ERROR_GEN_MEMORY_EXHAUSTED,                          .http_status = 503,
+     .message = "memory exhausted"},
+    {.id = ICECAST_ERROR_SOURCE_MOUNT_UNAVAILABLE,                      .http_status = 404 /* XXX */,
+     .message = "Mount unavailable"},
+    {.id = ICECAST_ERROR_SOURCE_STREAM_PREPARATION_ERROR,               .http_status = 500 /* XXX */,
+     .message = "Stream preparation error"},
+    {.id = ICECAST_ERROR_XSLT_PARSE,                                    .http_status = 404 /* XXX */,
+     .message = "Could not parse XSLT file"},
+    {.id = ICECAST_ERROR_XSLT_problem,                                  .http_status = 500,
+     .message = "XSLT problem"}
+};
+
+const icecast_error_t * error_get_by_id(int id) {
+    size_t i;
+
+    for (i = 0; i < (sizeof(__errors)/sizeof(*__errors)); i++) {
+        if (__errors[i].id == id) {
+            return &(__errors[i]);
+        }
+    }
+
+    return NULL;
+}
+
diff --git a/src/errors.h b/src/errors.h
new file mode 100644
index 00000000..472f5950
--- /dev/null
+++ b/src/errors.h
@@ -0,0 +1,62 @@
+/* Icecast
+ *
+ * This program is distributed under the GNU General Public License, version 2.
+ * A copy of this license is included with this source.
+ *
+ * Copyright 2018,      Philipp "ph3-der-loewe" Schafft <lion@lion.leolix.org>
+ */
+
+#ifndef __ERRORS_H__
+#define __ERRORS_H__
+
+#define ICECAST_ERROR_ADMIN_DEST_NOT_RUNNING                   1
+#define ICECAST_ERROR_ADMIN_METADAT_BADCALL                    2
+#define ICECAST_ERROR_ADMIN_METADAT_NO_SUCH_ACTION             3
+#define ICECAST_ERROR_ADMIN_MISSING_PARAMETER                  4
+#define ICECAST_ERROR_ADMIN_missing_parameter                  5 /* what is this? */
+#define ICECAST_ERROR_ADMIN_MOUNT_NOT_ACCEPT_URL_UPDATES       6
+#define ICECAST_ERROR_ADMIN_NO_SUCH_DESTINATION                7
+#define ICECAST_ERROR_ADMIN_ROLEMGN_ADD_NOSYS                  8
+#define ICECAST_ERROR_ADMIN_ROLEMGN_DELETE_NOSYS               9
+#define ICECAST_ERROR_ADMIN_ROLEMGN_ROLE_NOT_FOUND             10
+#define ICECAST_ERROR_ADMIN_SOURCE_DOES_NOT_EXIST              11
+#define ICECAST_ERROR_ADMIN_SOURCE_IS_NOT_AVAILABLE            12
+#define ICECAST_ERROR_ADMIN_SUPPLIED_MOUNTPOINTS_ARE_IDENTICAL 13
+#define ICECAST_ERROR_ADMIN_UNRECOGNISED_COMMAND               14
+#define ICECAST_ERROR_AUTH_BUSY                                15
+#define ICECAST_ERROR_CON_CONTENT_TYPE_NOSYS                   16
+#define ICECAST_ERROR_CON_INTERNAL_FORMAT_ALLOC_ERROR          17
+#define ICECAST_ERROR_CON_MISSING_PASS_PARAMETER               18
+#define ICECAST_ERROR_CON_MOUNT_IN_USE                         19
+#define ICECAST_ERROR_CON_MOUNTPOINT_NOT_STARTING_WITH_SLASH   20
+#define ICECAST_ERROR_CON_NO_CONTENT_TYPE_GIVEN                21
+#define ICECAST_ERROR_CON_PER_CRED_CLIENT_LIMIT                22
+#define ICECAST_ERROR_CON_rejecting_client_for_whatever_reason 23 /* ??? */
+#define ICECAST_ERROR_CON_SOURCE_CLIENT_LIMIT                  24
+#define ICECAST_ERROR_CON_UNIMPLEMENTED                        25
+#define ICECAST_ERROR_CON_UNKNOWN_REQUEST                      26
+#define ICECAST_ERROR_CON_UPGRADE_ERROR                        27
+#define ICECAST_ERROR_FSERV_FILE_NOT_FOUND                     28
+#define ICECAST_ERROR_FSERV_FILE_NOT_READABLE                  29
+#define ICECAST_ERROR_FSERV_REQUEST_RANGE_NOT_SATISFIABLE      30
+#define ICECAST_ERROR_GEN_BUFFER_REALLOC                       31
+#define ICECAST_ERROR_GEN_CLIENT_LIMIT                         32
+#define ICECAST_ERROR_GEN_CLIENT_NEEDS_TO_AUTHENTICATE         33
+#define ICECAST_ERROR_GEN_HEADER_GEN_FAILED                    34
+#define ICECAST_ERROR_GEN_MEMORY_EXHAUSTED                     35
+#define ICECAST_ERROR_SOURCE_MOUNT_UNAVAILABLE                 36
+#define ICECAST_ERROR_SOURCE_STREAM_PREPARATION_ERROR          37
+#define ICECAST_ERROR_XSLT_PARSE                               38
+#define ICECAST_ERROR_XSLT_problem                             39
+
+struct icecast_error_tag {
+    const int id;
+    const int http_status;
+    const char *message;
+};
+
+typedef struct icecast_error_tag icecast_error_t;
+
+const icecast_error_t * error_get_by_id(int id);
+
+#endif  /* __ERRORS_H__ */
diff --git a/src/fserve.c b/src/fserve.c
index 94a6e961..02a1bc25 100644
--- a/src/fserve.c
+++ b/src/fserve.c
@@ -8,7 +8,7 @@
  *                      oddsock <oddsock@xiph.org>,
  *                      Karl Heyes <karl@xiph.org>
  *                      and others (see AUTHORS for details).
- * Copyright 2011,      Philipp "ph3-der-loewe" Schafft <lion@lion.leolix.org>.
+ * Copyright 2011-2018, Philipp "ph3-der-loewe" Schafft <lion@lion.leolix.org>.
  */
 
 #ifdef HAVE_CONFIG_H
@@ -51,6 +51,7 @@
 #include "global.h"
 #include "refbuf.h"
 #include "client.h"
+#include "errors.h"
 #include "stats.h"
 #include "format.h"
 #include "logging.h"
@@ -440,7 +441,7 @@ int fserve_client_create (client_t *httpclient, const char *path)
         if (m3u_requested == 0 && xslt_playlist_requested == NULL)
         {
             ICECAST_LOG_WARN("req for file \"%H\" %s", fullpath, strerror (errno));
-            client_send_error(httpclient, 404, 0, "The file you requested could not be found");
+            client_send_error_by_id(httpclient, ICECAST_ERROR_FSERV_FILE_NOT_FOUND);
             free (fullpath);
             return -1;
         }
@@ -469,7 +470,7 @@ int fserve_client_create (client_t *httpclient, const char *path)
                                       "audio/x-mpegurl", NULL, "", NULL, httpclient);
         if (ret == -1 || ret >= (BUFSIZE - 512)) { /* we want at least 512 bytes left for the content of the playlist */
             ICECAST_LOG_ERROR("Dropping client as we can not build response headers.");
-            client_send_error(httpclient, 500, 0, "Header generation failed.");
+            client_send_error_by_id(httpclient, ICECAST_ERROR_GEN_HEADER_GEN_FAILED);
             free(sourceuri);
             return -1;
         }
@@ -517,7 +518,7 @@ int fserve_client_create (client_t *httpclient, const char *path)
     if (config->fileserve == 0)
     {
         ICECAST_LOG_DEBUG("on demand file \"%H\" refused. Serving static files has been disabled in the config", fullpath);
-        client_send_error(httpclient, 404, 0, "The file you requested could not be found");
+        client_send_error_by_id(httpclient, ICECAST_ERROR_FSERV_FILE_NOT_FOUND);
         config_release_config();
         free(fullpath);
         return -1;
@@ -526,7 +527,7 @@ int fserve_client_create (client_t *httpclient, const char *path)
 
     if (S_ISREG (file_buf.st_mode) == 0)
     {
-        client_send_error(httpclient, 404, 0, "The file you requested could not be found");
+        client_send_error_by_id(httpclient, ICECAST_ERROR_FSERV_FILE_NOT_FOUND);
         ICECAST_LOG_WARN("found requested file but there is no handler for it: %H", fullpath);
         free (fullpath);
         return -1;
@@ -536,7 +537,7 @@ int fserve_client_create (client_t *httpclient, const char *path)
     if (file == NULL)
     {
         ICECAST_LOG_WARN("Problem accessing file \"%H\"", fullpath);
-        client_send_error(httpclient, 404, 0, "File not readable");
+        client_send_error_by_id(httpclient, ICECAST_ERROR_FSERV_FILE_NOT_READABLE);
         free (fullpath);
         return -1;
     }
@@ -585,7 +586,7 @@ int fserve_client_create (client_t *httpclient, const char *path)
                                                 NULL, NULL, httpclient);
                 if (bytes == -1 || bytes >= (BUFSIZE - 512)) { /* we want at least 512 bytes left */
                     ICECAST_LOG_ERROR("Dropping client as we can not build response headers.");
-                    client_send_error(httpclient, 500, 0, "Header generation failed.");
+                    client_send_error_by_id(httpclient, ICECAST_ERROR_GEN_HEADER_GEN_FAILED);
                     return -1;
                 }
                 bytes += snprintf (httpclient->refbuf->data + bytes, BUFSIZE - bytes,
@@ -616,7 +617,7 @@ int fserve_client_create (client_t *httpclient, const char *path)
                                         NULL, NULL, httpclient);
         if (bytes == -1 || bytes >= (BUFSIZE - 512)) { /* we want at least 512 bytes left */
             ICECAST_LOG_ERROR("Dropping client as we can not build response headers.");
-            client_send_error(httpclient, 500, 0, "Header generation failed.");
+            client_send_error_by_id(httpclient, ICECAST_ERROR_GEN_HEADER_GEN_FAILED);
             fclose(file);
             return -1;
         }
@@ -636,7 +637,7 @@ int fserve_client_create (client_t *httpclient, const char *path)
 
 fail:
     fclose (file);
-    client_send_error(httpclient, 416, 1, "Request Range Not Satisfiable\r\n");
+    client_send_error_by_id(httpclient, ICECAST_ERROR_FSERV_REQUEST_RANGE_NOT_SATISFIABLE);
     return -1;
 }
 
@@ -669,7 +670,7 @@ int fserve_add_client (client_t *client, FILE *file)
     ICECAST_LOG_DEBUG("Adding client %p to file serving engine", client);
     if (fclient == NULL)
     {
-        client_send_error(client, 404, 0, "memory exhausted");
+        client_send_error_by_id(client, ICECAST_ERROR_GEN_MEMORY_EXHAUSTED);
         return -1;
     }
     fclient->file = file;
@@ -691,7 +692,7 @@ void fserve_add_client_callback (client_t *client, fserve_callback_t callback, v
     ICECAST_LOG_DEBUG("Adding client to file serving engine");
     if (fclient == NULL)
     {
-        client_send_error(client, 404, 0, "memory exhausted");
+        client_send_error_by_id(client, ICECAST_ERROR_GEN_MEMORY_EXHAUSTED);
         return;
     }
     fclient->file = NULL;
diff --git a/src/main.c b/src/main.c
index 27b688f3..7ee01a5a 100644
--- a/src/main.c
+++ b/src/main.c
@@ -8,7 +8,7 @@
  *                      oddsock <oddsock@xiph.org>,
  *                      Karl Heyes <karl@xiph.org>,
  *                      and others (see AUTHORS for details).
- * Copyright 2011-2014, Philipp "ph3-der-loewe" Schafft <lion@lion.leolix.org>,
+ * Copyright 2011-2018, Philipp "ph3-der-loewe" Schafft <lion@lion.leolix.org>,
  * Copyright 2014,      Thomas B. Ruecker <thomas@ruecker.fi>.
  */
 
diff --git a/src/source.c b/src/source.c
index b4a6f265..b7ace96a 100644
--- a/src/source.c
+++ b/src/source.c
@@ -8,7 +8,7 @@
  *                      oddsock <oddsock@xiph.org>,
  *                      Karl Heyes <karl@xiph.org>
  *                      and others (see AUTHORS for details).
- * Copyright 2012-2014, Philipp "ph3-der-loewe" Schafft <lion@lion.leolix.org>,
+ * Copyright 2012-2018, Philipp "ph3-der-loewe" Schafft <lion@lion.leolix.org>,
  */
 
 /* -*- c-basic-offset: 4; indent-tabs-mode: nil; -*- */
@@ -48,6 +48,7 @@
 #include "global.h"
 #include "refbuf.h"
 #include "client.h"
+#include "errors.h"
 #include "stats.h"
 #include "logging.h"
 #include "cfgfile.h"
@@ -961,10 +962,10 @@ static int _free_client(void *key)
     switch (client->respcode) {
         case 0:
             /* if no response has been sent then send a 404 */
-            client_send_error(client, 404, 0, "Mount unavailable");
+            client_send_error_by_id(client, ICECAST_ERROR_SOURCE_MOUNT_UNAVAILABLE);
             break;
         case 500:
-            client_send_error(client, 500, 0, "Stream preparation error");
+            client_send_error_by_id(client, ICECAST_ERROR_SOURCE_STREAM_PREPARATION_ERROR);
             break;
         default:
             client_destroy(client);
diff --git a/src/util.c b/src/util.c
index d815edf5..a8c6e7a2 100644
--- a/src/util.c
+++ b/src/util.c
@@ -5,7 +5,7 @@
  *                      oddsock <oddsock@xiph.org>,
  *                      Karl Heyes <karl@xiph.org>
  *                      and others (see AUTHORS for details).
- *  Copyright 2012-2015 Philipp "ph3-der-loewe" Schafft <lion@lion.leolix.org>
+ *  Copyright 2012-2018 Philipp "ph3-der-loewe" Schafft <lion@lion.leolix.org>
  *
  *  This program is distributed under the GNU General Public License, version 2.
  *  A copy of this license is included with this source.
@@ -819,13 +819,10 @@ static inline void __free_args(struct __args *arg, size_t len)
     size_t i;
 
     for (i = 0; i < len; i++) {
-        free(arg->group);
+        free(arg[i].group);
     }
 }
 
-    // Accept: text/html, application/xhtml+xml, */*
-    // Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
-
 static inline int __parse_q(const char *str)
 {
     int ret = 0;
diff --git a/src/util.h b/src/util.h
index 469aca72..cdc30fbe 100644
--- a/src/util.h
+++ b/src/util.h
@@ -5,7 +5,7 @@
  *                      oddsock <oddsock@xiph.org>,
  *                      Karl Heyes <karl@xiph.org>
  *                      and others (see AUTHORS for details).
- *  Copyright 2012-2015 Philipp "ph3-der-loewe" Schafft <lion@lion.leolix.org>
+ *  Copyright 2012-2018 Philipp "ph3-der-loewe" Schafft <lion@lion.leolix.org>
  *
  *  This program is distributed under the GNU General Public License, version 2.
  *  A copy of this license is included with this source.
diff --git a/src/xslt.c b/src/xslt.c
index 2e6797a5..09af35b4 100644
--- a/src/xslt.c
+++ b/src/xslt.c
@@ -8,6 +8,7 @@
  *                      oddsock <oddsock@xiph.org>,
  *                      Karl Heyes <karl@xiph.org>
  *                      and others (see AUTHORS for details).
+ * Copyright 2012-2018, Philipp "ph3-der-loewe" Schafft <lion@lion.leolix.org>,
  */
 
 #ifdef HAVE_CONFIG_H
@@ -50,6 +51,7 @@
 #include "global.h"
 #include "refbuf.h"
 #include "client.h"
+#include "errors.h"
 #include "config.h"
 #include "stats.h"
 #include "fserve.h"
@@ -306,7 +308,7 @@ void xslt_transform(xmlDocPtr doc, const char *xslfilename, client_t *client)
     {
         thread_mutex_unlock(&xsltlock);
         ICECAST_LOG_ERROR("problem reading stylesheet \"%s\"", xslfilename);
-        client_send_error(client, 404, 0, "Could not parse XSLT file");
+        client_send_error_by_id(client, ICECAST_ERROR_XSLT_PARSE);
         return;
     }
 
@@ -350,7 +352,7 @@ void xslt_transform(xmlDocPtr doc, const char *xslfilename, client_t *client)
         ret = util_http_build_header(refbuf->data, full_len, 0, 0, 200, NULL, mediatype, charset, NULL, NULL, client);
         if (ret == -1) {
             ICECAST_LOG_ERROR("Dropping client as we can not build response headers.");
-            client_send_error(client, 500, 0, "Header generation failed.");
+            client_send_error_by_id(client, ICECAST_ERROR_GEN_HEADER_GEN_FAILED);
         } else {
             if ( full_len < (ret + (ssize_t)len + (ssize_t)64) ) {
                 void *new_data;
@@ -363,12 +365,12 @@ void xslt_transform(xmlDocPtr doc, const char *xslfilename, client_t *client)
                     ret = util_http_build_header(refbuf->data, full_len, 0, 0, 200, NULL, mediatype, charset, NULL, NULL, client);
                     if (ret == -1) {
                         ICECAST_LOG_ERROR("Dropping client as we can not build response headers.");
-                        client_send_error(client, 500, 0, "Header generation failed.");
+                        client_send_error_by_id(client, ICECAST_ERROR_GEN_HEADER_GEN_FAILED);
                         failed = 1;
                     }
                 } else {
                     ICECAST_LOG_ERROR("Client buffer reallocation failed. Dropping client.");
-                    client_send_error(client, 500, 0, "Buffer reallocation failed.");
+                    client_send_error_by_id(client, ICECAST_ERROR_GEN_BUFFER_REALLOC);
                     failed = 1;
                 }
             }
@@ -388,7 +390,7 @@ void xslt_transform(xmlDocPtr doc, const char *xslfilename, client_t *client)
     else
     {
         ICECAST_LOG_WARN("problem applying stylesheet \"%s\"", xslfilename);
-        client_send_error(client, 404, 0, "XSLT problem");
+        client_send_error_by_id(client, ICECAST_ERROR_XSLT_problem);
     }
     thread_mutex_unlock (&xsltlock);
     xmlFreeDoc(res);