Add support for the "sd_notify" protocol

[ngircd.git] / src / ngircd / sighandlers.c

diff --git a/src/ngircd/sighandlers.c b/src/ngircd/sighandlers.c
index 4ed1a1255f4498b3820856dd8736d2a86cf0d33c..56fd8aea2382a6d588220eb3a7ba1a241384d989 100644 (file)
--- a/src/ngircd/sighandlers.c
+++ b/src/ngircd/sighandlers.c
@@ -1,6 +1,6 @@
 /*
  * ngIRCd -- The Next Generation IRC Daemon
- * Copyright (c)2001-2015 Alexander Barton (alex@barton.de) and Contributors.
+ * Copyright (c)2001-2024 Alexander Barton (alex@barton.de) and Contributors.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -26,6 +26,11 @@
 #include <sys/wait.h>
 #include <time.h>
 
+#ifdef HAVE_SYS_UN_H
+# include <sys/socket.h>
+# include <sys/un.h>
+#endif
+
 #include "conn.h"
 #include "channel.h"
 #include "conf.h"
@@ -100,14 +105,17 @@ Rehash(void)
        unsigned old_nicklen;
 
        Log( LOG_NOTICE|LOG_snotice, "Re-reading configuration NOW!" );
+       Signal_NotifySvcMgr("RELOADING=1\n");
 
        /* Remember old server name and nickname length */
        strlcpy( old_name, Conf_ServerName, sizeof old_name );
        old_nicklen = Conf_MaxNickLength;
 
        /* Re-read configuration ... */
-       if (!Conf_Rehash( ))
+       if (!Conf_Rehash()) {
+               Signal_NotifySvcMgr("READY=1\n");
                return;
+       }
 
        /* Close down all listening sockets */
        Conn_ExitListeners( );
@@ -139,6 +147,7 @@ Rehash(void)
        Conn_SyncServerStruct( );
 
        Log( LOG_NOTICE|LOG_snotice, "Re-reading of configuration done." );
+       Signal_NotifySvcMgr("READY=1\n");
 } /* Rehash */
 
 /**
@@ -339,4 +348,89 @@ Signals_Exit(void)
        signalpipe[0] = signalpipe[1] = 0;
 }
 
-/* -eof- */
+/**
+ * Notify the service manager using the "sd_notify" protocol.
+ *
+ * This function is based on the example notify() function shown in the
+ * sd_notify(3) manual page, with one significant difference: we keep the file
+ * descriptor open to reduce overhead when called multiple times.
+ *
+ * @param message: The message to pass to the service manager including "\n".
+ */
+GLOBAL void
+#if !defined(HAVE_SYS_UN_H) || !defined(SOCK_CLOEXEC)
+Signal_NotifySvcMgr(UNUSED const char *message)
+{
+       return;
+#else
+Signal_NotifySvcMgr(const char *message)
+{
+       struct sockaddr_un socket_addr;
+       const char *socket_path;
+       size_t path_length, message_length;
+       static int fd = NONE;
+
+       assert(message != NULL);
+       assert(message[0] != '\0');
+
+       if (fd == NONE) {
+               /* No socket to the service manager open: Check if a path name
+                * is given in the environment and try to open it! */
+               socket_path = getenv("NOTIFY_SOCKET");
+               if (!socket_path)
+                       return; /* No socket specified, nothing to do. */
+
+               /* Only AF_UNIX is supported, with path or abstract sockets */
+               if (socket_path[0] != '/' && socket_path[0] != '@') {
+                       Log(LOG_CRIT,
+                       "Failed to notify service manager: Unsupported socket path!");
+                       return;
+               }
+
+               path_length = strlen(socket_path);
+
+               /* Ensure there is room for NUL byte */
+               if (path_length >= sizeof(socket_addr.sun_path)) {
+                       Log(LOG_CRIT,
+                       "Failed to notify service manager: Socket path too long!");
+                       return;
+               }
+
+               memset(&socket_addr, 0, sizeof(struct sockaddr_un));
+               socket_addr.sun_family = AF_UNIX;
+               memcpy(socket_addr.sun_path, socket_path, path_length);
+
+               /* Support for abstract socket */
+               if (socket_addr.sun_path[0] == '@')
+                       socket_addr.sun_path[0] = 0;
+
+               fd = socket(AF_UNIX, SOCK_DGRAM | SOCK_CLOEXEC, 0);
+               if (fd < 0) {
+                       Log(LOG_CRIT,
+                           "Failed to notify service manager: %s [socket()]",
+                           strerror(errno));
+                       return;
+               }
+
+               if (connect(fd, (struct sockaddr *)&socket_addr,
+                           sizeof(struct sockaddr_un)) != 0) {
+                       Log(LOG_CRIT,
+                           "Failed to notify service manager: %s [connect()]",
+                           strerror(errno));
+                       close(fd);
+                       fd = NONE;
+                       return;
+               }
+       }
+
+       message_length = strlen(message);
+       ssize_t written = write(fd, message, message_length);
+       if (written != (ssize_t)message_length) {
+               Log(LOG_CRIT,
+                       "Failed to notify service manager: %s [write()]",
+                       strerror(errno));
+               close(fd);
+               fd = NONE;
+       }
+#endif
+}