dhcpcd: Rework daemonisation

Now that we spawn helper processes for priviledge separation,
we need to fork() and setssid() much earlier. Infact, pretty much
from the get go of starting up.

dhcpcd_daemonise now writes to the launcher signal pipe about the
result of "daemonisation", even though it's already deamonised at
this point.

This allows dhcpcd to keep the helper processes running when
started by the system init at boot.

1 files changed, 21 insertions, 12 deletions

diff --git a/src/privsep.c b/src/privsep.c
index 1ef46873..63d558a1 100644
--- a/src/privsep.c
+++ b/src/privsep.c
@@ -150,10 +150,26 @@ create_sp:
 	}
 
 	ctx->options |= DHCPCD_UNPRIV | DHCPCD_FORKED;
+	if (ctx->fork_fd != -1) {
+		close(ctx->fork_fd);
+		ctx->fork_fd = -1;
+	}
 	control_close(ctx);
 	pidfile_clean();
 	eloop_clear(ctx->eloop);
 
+	/* We are not root */
+	if (priv_fd != &ctx->ps_root_fd) {
+		ps_freeprocesses(ctx, recv_ctx);
+		close(ctx->ps_root_fd);
+		ctx->ps_root_fd = -1;
+	}
+
+	if (priv_fd != &ctx->ps_inet_fd) {
+		close(ctx->ps_inet_fd);
+		ctx->ps_inet_fd = -1;
+	}
+
 	if (eloop_signal_set_cb(ctx->eloop,
 	    dhcpcd_signals, dhcpcd_signals_len, signal_cb, ctx) == -1)
 	{
@@ -171,21 +187,14 @@ create_sp:
 		goto errexit;
 	}
 
-	/* We are not root */
-	if (priv_fd != &ctx->ps_root_fd) {
-		ps_freeprocesses(ctx, recv_ctx);
-		close(ctx->ps_root_fd);
-		ctx->ps_root_fd = -1;
-	}
-
-	if (priv_fd != &ctx->ps_inet_fd) {
-		close(ctx->ps_inet_fd);
-		ctx->ps_inet_fd = -1;
-	}
-
 	if (callback(recv_ctx) == -1)
 		goto errexit;
 
+#if 0
+	/* XXX Why does this cause processes to exit? */
+	close_std();
+#endif
+
 	if (pw == NULL)
 		return 0;