mesg applet by Manuel Novoa III

5 files changed, 70 insertions, 0 deletions

diff --git a/include/applets.h b/include/applets.h
index 38d75344f..f6a840024 100644
--- a/include/applets.h
+++ b/include/applets.h
@@ -293,6 +293,9 @@
 #ifdef CONFIG_MD5SUM
         APPLET(md5sum, md5sum_main, _BB_DIR_USR_BIN, _BB_SUID_NEVER)
 #endif
+#ifdef CONFIG_MESG
+        APPLET(mesg, mesg_main, _BB_DIR_USR_BIN, _BB_SUID_NEVER)
+#endif
 #ifdef CONFIG_MKDIR
         APPLET(mkdir, mkdir_main, _BB_DIR_BIN, _BB_SUID_NEVER)
 #endif
diff --git a/include/usage.h b/include/usage.h
index 98b81cf1d..ee697150b 100644
--- a/include/usage.h
+++ b/include/usage.h
@@ -1149,6 +1149,13 @@
         "busybox: OK\n" \
         "^D\n"
 
+#define mesg_trivial_usage \
+        "mesg [y|n]"
+#define mesg_full_usage \
+        "mesg [Y|N], controls write access to your terminal\n" \
+        "\ty\tAllow write access to your terminal.\n" \
+        "\tn\tDisallow write access to your terminal.\n"
+
 #define mkdir_trivial_usage \
         "[OPTION] DIRECTORY..."
 #define mkdir_full_usage \
diff --git a/init/Makefile.in b/init/Makefile.in
index 8cc95264d..cd3ead839 100644
--- a/init/Makefile.in
+++ b/init/Makefile.in
@@ -25,6 +25,7 @@ endif
 INIT-y:=
 INIT-$(CONFIG_HALT)                     += halt.o
 INIT-$(CONFIG_INIT)                     += init.o
+INIT-$(CONFIG_MESG)                     += mesg.o
 INIT-$(CONFIG_POWEROFF)                 += poweroff.o
 INIT-$(CONFIG_REBOOT)                   += reboot.o
 INIT-$(CONFIG_START_STOP_DAEMON)        += start_stop_daemon.o
diff --git a/init/config.in b/init/config.in
index 58fe1d8e3..e4aa4fbba 100644
--- a/init/config.in
+++ b/init/config.in
@@ -22,6 +22,7 @@ fi
 
 bool 'start-stop-daemon'            CONFIG_START_STOP_DAEMON
 bool 'run-parts'                    CONFIG_RUN_PARTS
+bool 'mesg'                         CONFIG_MESG
         
 endmenu
 
diff --git a/init/mesg.c b/init/mesg.c
new file mode 100644
index 000000000..f9b46e029
--- /dev/null
+++ b/init/mesg.c
@@ -0,0 +1,58 @@
+/*
+ *  mesg implementation for busybox
+ *
+ *  Copyright (c) 2002 Manuel Novoa III  <mjn3@codepoet.org>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+#include <unistd.h>
+#include <stdlib.h>
+#include "libbb.h"
+
+#ifdef USE_TTY_GROUP
+#define S_IWGRP_OR_S_IWOTH      S_IWGRP
+#else
+#define S_IWGRP_OR_S_IWOTH      (S_IWGRP | S_IWOTH)
+#endif
+
+extern int mesg_main(int argc, char *argv[])
+{
+        struct stat sb;
+        char *tty;
+        char c;
+
+        if ((--argc == 0)
+                || ((argc == 1) && (((c = **++argv) == 'y') || (c == 'n')))) {
+                if ((tty = ttyname(STDERR_FILENO)) == NULL) {
+                        tty = "ttyname";
+                } else if (stat(tty, &sb) == 0) {
+                        if (argc == 0) {
+                                puts(((sb.st_mode & (S_IWGRP | S_IWOTH)) ==
+                                          0) ? "is n" : "is y");
+                                return EXIT_SUCCESS;
+                        }
+                        if (chmod
+                                (tty,
+                                 (c ==
+                                  'y') ? sb.st_mode | (S_IWGRP_OR_S_IWOTH) : sb.
+                                 st_mode & ~(S_IWGRP | S_IWOTH)) == 0) {
+                                return EXIT_SUCCESS;
+                        }
+                }
+                perror_msg_and_die("%s", tty);
+        }
+        show_usage();
+}