dc: fix "dc does_not_exist" SEGVing

[oweals/busybox.git] / miscutils / crontab.c

diff --git a/miscutils/crontab.c b/miscutils/crontab.c
index 16d7fdf69c9855cf084a27d3d1f57b831d70f479..4787fa08f5dee66b84fac6e2eece54e3ed5cfac2 100644 (file)
--- a/miscutils/crontab.c
+++ b/miscutils/crontab.c
@@ -9,6 +9,29 @@
  *
  * Licensed under GPLv2 or later, see file LICENSE in this source tree.
  */
+//config:config CRONTAB
+//config:      bool "crontab (9.7 kb)"
+//config:      default y
+//config:      help
+//config:      Crontab manipulates the crontab for a particular user. Only
+//config:      the superuser may specify a different user and/or crontab directory.
+//config:      Note that busybox binary must be setuid root for this applet to
+//config:      work properly.
+
+/* Needs to be run by root or be suid root - needs to change /var/spool/cron* files: */
+//applet:IF_CRONTAB(APPLET(crontab, BB_DIR_USR_BIN, BB_SUID_REQUIRE))
+
+//kbuild:lib-$(CONFIG_CRONTAB) += crontab.o
+
+//usage:#define crontab_trivial_usage
+//usage:       "[-c DIR] [-u USER] [-ler]|[FILE]"
+//usage:#define crontab_full_usage "\n\n"
+//usage:       "       -c      Crontab directory"
+//usage:     "\n       -u      User"
+//usage:     "\n       -l      List crontab"
+//usage:     "\n       -e      Edit crontab"
+//usage:     "\n       -r      Delete crontab"
+//usage:     "\n       FILE    Replace crontab by FILE ('-': stdin)"
 
 #include "libbb.h"
 
@@ -45,28 +68,6 @@ static void edit_file(const struct passwd *pas, const char *file)
        bb_perror_msg_and_die("can't execute '%s'", ptr);
 }
 
-static int open_as_user(const struct passwd *pas, const char *file)
-{
-       pid_t pid;
-       char c;
-
-       pid = xvfork();
-       if (pid) { /* PARENT */
-               if (wait4pid(pid) == 0) {
-                       /* exitcode 0: child says it can read */
-                       return open(file, O_RDONLY);
-               }
-               return -1;
-       }
-
-       /* CHILD */
-       /* initgroups, setgid, setuid */
-       change_identity(pas);
-       /* We just try to read one byte. If it works, file is readable
-        * under this user. We signal that by exiting with 0. */
-       _exit(safe_read(xopen(file, O_RDONLY), &c, 1) < 0);
-}
-
 int crontab_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int crontab_main(int argc UNUSED_PARAM, char **argv)
 {
@@ -98,8 +99,9 @@ int crontab_main(int argc UNUSED_PARAM, char **argv)
                OPT_ler = OPT_l + OPT_e + OPT_r,
        };
 
-       opt_complementary = "?1:dr"; /* max one argument; -d implies -r */
-       opt_ler = getopt32(argv, "u:c:lerd", &user_name, &crontab_dir);
+       opt_ler = getopt32(argv, "^" "u:c:lerd" "\0" "?1:dr"/*max one arg; -d implies -r*/,
+                               &user_name, &crontab_dir
+       );
        argv += optind;
 
        if (sanitize_env_if_suid()) { /* Clears dangerous stuff, sets PATH */
@@ -127,10 +129,7 @@ int crontab_main(int argc UNUSED_PARAM, char **argv)
                if (!argv[0])
                        bb_show_usage();
                if (NOT_LONE_DASH(argv[0])) {
-                       src_fd = open_as_user(pas, argv[0]);
-                       if (src_fd < 0)
-                               bb_error_msg_and_die("user %s cannot read %s",
-                                               pas->pw_name, argv[0]);
+                       src_fd = xopen_as_uid_gid(argv[0], O_RDONLY, pas->pw_uid, pas->pw_gid);
                }
        }
 
@@ -185,7 +184,6 @@ int crontab_main(int argc UNUSED_PARAM, char **argv)
                        unlink(tmp_fname);
                /*free(tmp_fname);*/
                /*free(new_fname);*/
-
        } /* switch */
 
        /* Bump notification file.  Handle window where crond picks file up