Attempt #2 at fixing the file descriptor mess.

This commit defers daemonisation to the end of initialisation
as that makes it vastly simpler to get this right.

diff --git a/ircd/ircd.c b/ircd/ircd.c
index d249728ce4913a23a58348e5b58e9ce3fdb0874b..de8e80a4fe95084d441e61008a4ea2f315ba1322 100644 (file)
--- a/ircd/ircd.c
+++ b/ircd/ircd.c
@@ -187,50 +187,6 @@ ircd_shutdown(const char *reason)
        exit(0);
 }
 
-/*
- * print_startup - print startup information
- */
-static void
-print_startup(int pid)
-{
-       int fd;
-
-#ifndef _WIN32
-       close(1);
-       fd = open("/dev/null", O_RDWR);
-       if (fd == -1) {
-               perror("open /dev/null");
-               exit(EXIT_FAILURE);
-       }
-       if (fd == 0)
-               fd = dup(fd);
-       if (fd != 1)
-               abort();
-#endif
-       inotice("now running in %s mode from %s as pid %d ...",
-              !server_state_foreground ? "background" : "foreground",
-               ConfigFileEntry.dpath, pid);
-
-#ifndef _WIN32
-       /* let the parent process know the initialization was successful
-        * -- jilles */
-       if (!server_state_foreground)
-       {
-               /* GCC complains on Linux if we don't check the value of write pedantically.
-                * Technically you're supposed to check the value, yes, but it probably can't fail.
-                * No, casting to void is of no use to shut the warning up. You HAVE to use the value.
-                * --Elizfaox
-                */
-               if(write(0, ".", 1) < 1)
-                       abort();
-       }
-       if (dup2(1, 0) == -1)
-               abort();
-       if (dup2(1, 2) == -1)
-               abort();
-#endif
-}
-
 /*
  * init_sys
  *
@@ -259,21 +215,16 @@ init_sys(void)
        maxconnections = MAXCONNECTIONS;
 }
 
+#ifndef _WIN32
 static int
 make_daemon(void)
 {
-#ifndef _WIN32
-       int pid;
-       int pip[2];
-       char c;
+       int pid, nullfd, fdx;
+
+       /* The below is approximately what daemon(1, 0) does, but
+          we need control over the parent after forking to print
+          the startup message -- Aaron */
 
-       if (pipe(pip) < 0)
-       {
-               perror("pipe");
-               exit(EXIT_FAILURE);
-       }
-       dup2(pip[1], 0);
-       close(pip[1]);
        if((pid = fork()) < 0)
        {
                perror("fork");
@@ -281,25 +232,30 @@ make_daemon(void)
        }
        else if(pid > 0)
        {
-               close(0);
-               /* Wait for initialization to finish, successfully or
-                * unsuccessfully. Until this point the child may still
-                * write to stdout/stderr.
-                * -- jilles */
-               if (read(pip[0], &c, 1) > 0)
-                       exit(EXIT_SUCCESS);
-               else
-                       exit(EXIT_FAILURE);
+               inotice("now running in background mode from %s as pid %d ...",
+                       ConfigFileEntry.dpath, pid);
+
+               exit(EXIT_SUCCESS);
        }
 
-       close(pip[0]);
-       setsid();
-/*     fclose(stdin);
-       fclose(stdout);
-       fclose(stderr); */
-#endif
+       if((nullfd = open("/dev/null", O_RDWR)) < 0)
+       {
+               perror("open /dev/null");
+               exit(EXIT_FAILURE);
+       }
+
+       for(fdx = 0; fdx <= 2; fdx++)
+               if (fdx != nullfd)
+                       (void) dup2(nullfd, fdx);
+
+       if(nullfd > 2)
+               (void) close(nullfd);
+
+       (void) setsid();
+
        return 0;
 }
+#endif
 
 static int printVersion = 0;
 
@@ -768,9 +724,6 @@ charybdis_main(int argc, char * const argv[])
        if(!testing_conf)
        {
                check_pidfile(pidFileName);
-
-               if(!server_state_foreground)
-                       make_daemon();
                inotice("starting %s ...", ircd_version);
                inotice("%s", rb_lib_version());
        }
@@ -885,7 +838,6 @@ charybdis_main(int argc, char * const argv[])
        construct_umodebuf();
 
        check_class();
-       write_pidfile(pidFileName);
        load_help();
        open_logfiles();
 
@@ -906,7 +858,15 @@ charybdis_main(int argc, char * const argv[])
        if(splitmode)
                check_splitmode_ev = rb_event_add("check_splitmode", check_splitmode, NULL, 5);
 
-       print_startup(getpid());
+       if(server_state_foreground)
+               inotice("now running in foreground mode from %s as pid %d ...",
+                       ConfigFileEntry.dpath, getpid());
+#ifndef _WIN32
+       else
+               make_daemon();
+#endif
+
+       write_pidfile(pidFileName);
 
        rb_lib_loop(0);