merge with 0.30.213

[util-vserver.git] / src / fakerunlevel.c

diff --git a/src/fakerunlevel.c b/src/fakerunlevel.c
index 3ddcfe9..f429528 100644 (file)
--- a/src/fakerunlevel.c
+++ b/src/fakerunlevel.c
@@ -1,4 +1,4 @@
-// $Id: fakerunlevel.c,v 1.1 2003/09/29 22:01:57 ensc Exp $
+// $Id: fakerunlevel.c 1022 2004-02-27 04:42:10Z ensc $
 
 // Copyright (C) 2003 Enrico Scholz <enrico.scholz@informatik.tu-chemnitz.de>
 // based on fakerunlevel.cc by Jacques Gelinas
@@ -22,52 +22,96 @@
        This is used when a vserver lack a private init process
        so runlevel properly report the fake runlevel.
 */
+#ifdef HAVE_CONFIG_H
+#  include <config.h>
+#endif
+
+#include "util.h"
+
 #include <utmp.h>
 #include <stdio.h>
 #include <string.h>
 #include <stdlib.h>
 #include <errno.h>
+#include <fcntl.h>
+#include <grp.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+#define ENSC_WRAPPERS_PREFIX   "fakerunlevel: "
+#define ENSC_WRAPPERS_UNISTD   1
+#define ENSC_WRAPPERS_FCNTL    1
+#include <wrappers.h>
+
+int    wrapper_exit_code = 1;
 
-static void usage()
+static void
+showHelp(int fd, int exit_code)
 {
-       fprintf (stderr,"fakerunlevel version %s\n",VERSION);
-       fprintf (stderr
-               ,"\n"
-                "fakerunlevel runlevel utmp_file\n"
-                "\n"
-                "Put a runlevel record in file utmp_file\n");
+  WRITE_MSG(fd,
+           "Usage: fakerunlevel <runlevel> <utmp_file>\n\n"
+           "Put a runlevel record in file <utmp_file>\n\n"
+           "Please report bugs to " PACKAGE_BUGREPORT "\n");
+
+  exit(exit_code);
 }
 
-int main (int argc, char *argv[])
+static void
+showVersion()
 {
-       if (argc != 3){
-               usage();
-       }else{
-               int runlevel = atoi(argv[1]);
-               const char *fname = argv[2];
-               if (runlevel < 1 || runlevel > 5){
-                       usage();
-               }else{
-                       // Make sure the file exist
-                       FILE *fout = fopen (fname,"a");
-                       if (fout == NULL){
-                               fprintf (stderr,"Can't open file %s (%s)\n",fname
-                                       ,strerror(errno));
-                       }else{
-                               struct utmp ut;
-
-                               fclose (fout);
-                               utmpname (fname);
-                               setutent();
-                               memset (&ut,0,sizeof(ut));
-                               ut.ut_type = RUN_LVL;
-                               ut.ut_pid = ('#' << 8) + runlevel+'0';
-                               pututline (&ut);
-                               endutent();
-                       }
-               }
-       }
-
-       return 0;
+  WRITE_MSG(1,
+           "fakerunlevel " VERSION "\n"
+           "This program is part of " PACKAGE_STRING "\n\n"
+           "Copyright (C) 2003 Enrico Scholz\n"
+           VERSION_COPYRIGHT_DISCLAIMER);
+  exit(0);
 }
 
+int main (int argc, char *argv[])
+{
+  if (argc==1) showHelp(2,1);
+  if (strcmp(argv[1], "--help")==0)    showHelp(1,0);
+  if (strcmp(argv[1], "--version")==0) showVersion();
+  if (argc!=3) showHelp(2,1);
+
+  {
+    int  const                 runlevel = atoi(argv[1]);
+    char const * const fname    = argv[2];
+    int                        fd;
+    struct utmp        ut;
+    
+    gid_t              gid;
+    char               *gid_str = getenv("UTMP_GID");
+    
+    if (runlevel<0 || runlevel>6) showHelp(2,1);
+
+    Echroot(".");
+    Echdir("/");
+
+      // Real NSS is too expensive/insecure in this state; therefore, use the
+      // value detected at ./configure stage or overridden by $UTMP_GID
+      // env-variable
+    gid = gid_str ? atoi(gid_str) : UTMP_GID;
+    Esetgroups(1, &gid);
+    Esetgid(gid);
+
+    if (getgid()!=gid) {
+      WRITE_MSG(2, "fakerunlevel: Failed to set group\n");
+      return EXIT_FAILURE;
+    }
+
+    umask(002);
+    fd = EopenD(fname, O_WRONLY|O_CREAT|O_APPEND, 0664);
+    Eclose(fd);
+
+    utmpname (fname);
+    setutent();
+    memset (&ut,0,sizeof(ut));
+    ut.ut_type = RUN_LVL;
+    ut.ut_pid  = ('#' << 8) + runlevel+'0';
+    pututline (&ut);
+    endutent();
+  }
+
+  return EXIT_SUCCESS;
+}