further idmapd update

diff --git a/ChangeLog b/ChangeLog
index 424cd554ad4e7c4fdad4617c7400d53c58d7c863..4f9839deda0a7b8b93b61564a038f0e9a6ef3154 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -16,6 +16,9 @@
        * utils/idmapd/idmapd.c: Reopen nfsd files on sighup.  Allows us
        to start up client side only (even when nfsd module not loaded),
        and then sighup later after insmodding nfsd module. 
+       * utils/idmapd/idmapd.c: Make sure we catch all errors on
+       daemonizing by waiting for child to report succesfull startup
+       using a pipe. 
 
        
 2004-11-22 NeilBrown <neilb@cse.unsw.edu.au>

diff --git a/utils/idmapd/idmapd.c b/utils/idmapd/idmapd.c
index e965563ac045df75d25735c7b5ea67edb063e067..a5d4f723a660eda5d948e171db3e4f042242a90a 100644 (file)
--- a/utils/idmapd/idmapd.c
+++ b/utils/idmapd/idmapd.c
@@ -128,7 +128,8 @@ static void nfsdreopen(void);
 size_t  strlcat(char *, const char *, size_t);
 size_t  strlcpy(char *, const char *, size_t);
 ssize_t atomicio(ssize_t (*)(), int, void *, size_t);
-int     daemon(int, int);
+void    mydaemon(int, int);
+void    release_parent();
 
 static int verbose = 0;
 static char domain[512];
@@ -252,7 +253,7 @@ main(int argc, char **argv)
                warnx("Using domain \"%s\"", domain);
 
        if (!fg)
-               daemon(0, 0);
+               mydaemon(0, 0);
 
        event_init();
 
@@ -294,6 +295,8 @@ main(int argc, char **argv)
        if (nfsdret != 0 && fd == 0)
                errx(1, "Neither NFS client nor NFSd found");
 
+       release_parent();
+
        if (event_dispatch() < 0)
                errx(1, "event_dispatch: returns errno %d (%s)", errno, strerror(errno));
        /* NOTREACHED */
@@ -820,3 +823,69 @@ getfield(char **bpp, char *fld, size_t fldsz)
 
        return (0);
 }
+/*
+ * mydaemon creates a pipe between the partent and child
+ * process. The parent process will wait until the
+ * child dies or writes a '1' on the pipe signaling
+ * that it started successfully.
+ */
+int pipefds[2] = { -1, -1};
+
+void
+mydaemon(int nochdir, int noclose)
+{
+       int pid, status, tempfd, fdmax, filedes;
+
+       if (pipe(pipefds) < 0)
+               err(1, "mydaemon: pipe() failed: errno %d (%s)\n", errno, strerror(errno));
+
+       if ((pid = fork ()) < 0)
+               err(1, "mydaemon: fork() failed: errno %d (%s)\n", errno, strerror(errno));
+
+       if (pid != 0) {
+               /*
+                * Parent. Wait for status from child.
+                */
+               close(pipefds[1]);
+               if (read(pipefds[0], &status, 1) != 1)
+                       exit(1);
+               exit (0);
+       }
+       /* Child.       */
+       close(pipefds[0]);
+       setsid ();
+       if (nochdir == 0) {
+               if (chdir ("/") == -1)
+                       err(1, "mydaemon: chdir() failed: errno %d (%s)\n", errno, strerror(errno));
+       }
+
+       while (pipefds[1] <= 2) {
+               pipefds[1] = dup(pipefds[1]);
+               if (pipefds[1] < 0)
+                       err(1, "mydaemon: dup() failed: errno %d (%s)\n", errno, strerror(errno));
+       }
+
+       if (noclose == 0) {
+               tempfd = open("/dev/null", O_RDWR);
+               close(0); dup2(tempfd, 0);
+               close(1); dup2(tempfd, 1);
+               close(2); dup2(tempfd, 2);
+               fdmax = sysconf (_SC_OPEN_MAX);
+               for (filedes = 3; filedes < fdmax; filedes++)
+                       if (filedes != pipefds[1])
+                               close (filedes);
+       }
+
+       return;
+}
+void
+release_parent()
+{
+       int status;
+
+       if (pipefds[1] > 0) {
+               write(pipefds[1], &status, 1);
+               close(pipefds[1]);
+               pipefds[1] = -1;
+       }
+}