Implement emergency shell.

* src/pies.c (main): Move init-specific command line
handling to sysvinit_parse_argv.
* src/pies.h (dfl_level): Remove extern.
(sysvinit_parse_argv): New proto.
* src/sysvinit.c (sysvinit_parse_argv): New function.
(sysvinit_begin): Start emergency shell, if requested.

4 files changed, 95 insertions, 25 deletions

diff --git a/src/pies.c b/src/pies.c
index 3734b47..653a865 100644
--- a/src/pies.c
+++ b/src/pies.c
@@ -1929,3 +1929,2 @@ main (int argc, char **argv)
 {
-  int index;
   pid_t pid;
@@ -2003,14 +2002,20 @@ main (int argc, char **argv)
 #endif
-      for (index = 1; index < argc; index++)
+      sysvinit_parse_argv (argc, argv);
+    }
+  else
+    {
+      int index;
+
+      parse_options (argc, argv, &index);
+      argc -= index;
+      argv += index;
+      
+      if (argc && !(command == COM_RESTART_COMPONENT
+		    || command == COM_TRACE_DEPEND
+		    || command == COM_TRACE_PREREQ))
 	{
-	  if (!strcmp (argv[index], "single") || !strcmp (argv[index], "-s"))
-	    dfl_level = 'S';
-	  else if (strchr("0123456789sS", argv[index][0]) && !argv[index][1])
-	    {
-	      dfl_level = toupper (argv[index][0]);
-	    }	  
+	  logmsg (LOG_ERR, "extra command line arguments");
+	  exit (EX_USAGE);
 	}
     }
-  else
-    parse_options (argc, argv, &index);
   
@@ -2061,11 +2066,2 @@ main (int argc, char **argv)
   
-  if (argc != index
-      && !(command == COM_RESTART_COMPONENT
-	   || command == COM_TRACE_DEPEND
-	   || command == COM_TRACE_PREREQ))
-    {
-      logmsg (LOG_ERR, "extra command line arguments");
-      exit (EX_CONFIG);
-    }
-
   if (!control.url)
@@ -2088,3 +2084,3 @@ main (int argc, char **argv)
 	umask (pies_umask);
-      exit (request_restart_components (argc - index, argv + index));
+      exit (request_restart_components (argc, argv));
       
@@ -2104,3 +2100,3 @@ main (int argc, char **argv)
     case COM_TRACE_DEPEND:
-      components_trace (argv + index, depmap_row);
+      components_trace (argv, depmap_row);
       exit (0);
@@ -2108,3 +2104,3 @@ main (int argc, char **argv)
     case COM_TRACE_PREREQ: 
-      components_trace (argv + index, depmap_col);
+      components_trace (argv, depmap_col);
       exit (0);
diff --git a/src/pies.h b/src/pies.h
index bcce32a..4a6160f 100644
--- a/src/pies.h
+++ b/src/pies.h
@@ -293,3 +293,2 @@ extern char *console_device;
 extern int initdefault;
-extern int dfl_level;
 
@@ -525,2 +524,3 @@ void sysvinit_report (struct json_value *obj);
 int sysvinit_set_runlevel (int newlevel);
+void sysvinit_parse_argv (int argc, char **argv);
 
diff --git a/src/progman.c b/src/progman.c
index 8a5187c..1be7d27 100644
--- a/src/progman.c
+++ b/src/progman.c
@@ -1207,3 +1207,3 @@ prog_start (struct prog *prog)
       prog_execute (prog);
-
+      
       
@@ -1548,2 +1548,5 @@ progman_wake_sleeping (int onalrm)
 	{
+	  /* The following works on the assumption that prog->v.p.wait is
+	     set when enabling the component and gets cleared right after
+	     it has finished. */
 	  if (prog->v.p.status != status_running)
@@ -2413,2 +2416,3 @@ progman_stop_tag (const char *name)
 }
+
 /* EOF */
diff --git a/src/sysvinit.c b/src/sysvinit.c
index 2d0671c..0370fcc 100644
--- a/src/sysvinit.c
+++ b/src/sysvinit.c
@@ -18,2 +18,3 @@
 #include "prog.h"
+#include <sys/ioctl.h>
 #include <termios.h>
@@ -61,2 +62,3 @@ int initdefault;               /* Default runlevel */
 int dfl_level;
+int emergency_shell;
 
@@ -66,3 +68,3 @@ console_open (int mode)
   int i, fd;
-  
+
   for (i = 0; i < 5; i++)
@@ -648,2 +650,52 @@ unintr_sleep (unsigned n)
 
+static void
+start_shell (const char *shell)
+{
+  pid_t pid, rc;
+  int st;
+  struct sigaction act, old;
+
+  act.sa_flags = SA_RESTART;
+  act.sa_handler = SIG_DFL;
+  sigemptyset (&act.sa_mask);
+  sigaction (SIGCHLD, &act, &old);
+
+  pid = fork ();
+  if (pid == -1)
+    {
+      logmsg (LOG_CRIT, "cannot run `%s': fork failed: %s",
+	      shell, strerror (errno));
+      exit (1);
+    }
+
+  if (pid == 0)
+    {
+      int fd;
+
+      signal_setup (SIG_DFL);
+      setsid ();
+      
+      fd = console_open (O_RDWR|O_NOCTTY);
+      if (fd < 0) 
+	{
+	  logmsg (LOG_CRIT, "open(%s): %s",
+		  console_device, strerror (errno));
+	  exit (1);
+	}
+      ioctl (fd, TIOCSCTTY, 1);
+      dup (fd);
+      dup (fd);
+
+      execl (shell, shell, NULL);
+      _exit (127);
+    }
+  
+  while ((rc = wait (&st)) != pid)
+    if (rc == (pid_t) -1 && errno == ECHILD)
+      break;
+  
+  logmsg (LOG_CRIT, "shell finished");
+  sigaction (SIGCHLD, &old, NULL);
+}
+
 /* Memory allocation functions for INIT.  They may not fail, therefore
@@ -700,2 +752,4 @@ sysvinit_begin ()
   sysvinit_sysdep_begin ();
+  if (emergency_shell)
+    start_shell ("/sbin/sulogin");
 }
@@ -1142 +1196,17 @@ sysvinit_report (struct json_value *obj)
 }
+
+void
+sysvinit_parse_argv (int argc, char **argv)
+{
+  while (--argc)
+    {
+      int c;
+      char *arg = *++argv;
+      if (!strcmp (arg, "single") || !strcmp (arg, "-s"))
+	dfl_level = 'S';
+      else if (!strcmp (arg, "-b") || !strcmp (arg, "emergency"))
+	emergency_shell = 1;
+      else if (!arg[1] && strchr (valid_runlevels, (c = toupper (arg[0]))))
+	dfl_level = c;
+    }	  
+}