Fix /RESTART not closing file descriptors

Fixes issue #262 reported by @MistrX

1 files changed, 16 insertions, 0 deletions

diff --git a/src/commands/cmd_restart.cpp b/src/commands/cmd_restart.cpp
index dc5507548..bdbcfed35 100644
--- a/src/commands/cmd_restart.cpp
+++ b/src/commands/cmd_restart.cpp
@@ -45,6 +45,22 @@ CmdResult CommandRestart::Handle (const std::vector<std::string>& parameters, Us
 		ServerInstance->SNO->WriteGlobalSno('a', "RESTART command from %s, restarting server.", user->GetFullRealHost().c_str());
 
 		ServerInstance->SendError("Server restarting.");
+
+#ifndef _WIN32
+		/* XXX: This hack sets FD_CLOEXEC on all possible file descriptors, so they're closed if the execv() below succeeds.
+		 * Certainly, this is not a nice way to do things and it's slow when the fd limit is high.
+		 *
+		 * A better solution would be to set the close-on-exec flag for each fd we create (or create them with O_CLOEXEC),
+		 * however there is no guarantee that third party libs will do the same.
+		 */
+		for (int i = getdtablesize(); --i > 2;)
+		{
+			int flags = fcntl(i, F_GETFD);
+			if (flags != -1)
+				fcntl(i, F_SETFD, flags | FD_CLOEXEC);
+		}
+#endif
+
 		execv(ServerInstance->Config->cmdline.argv[0], ServerInstance->Config->cmdline.argv);
 		ServerInstance->SNO->WriteGlobalSno('a', "Failed RESTART - could not execute '%s' (%s)",
 			ServerInstance->Config->cmdline.argv[0], strerror(errno));