Changeset 3232 in MondoRescue for branches/3.2/mindi-busybox/init/mesg.c

Timestamp:

Jan 1, 2014, 12:47:38 AM (10 years ago)

Author:

Bruno Cornec

Message:

• Update mindi-busybox to 1.21.1

File:

• branches/3.2/mindi-busybox/init/mesg.c (modified) (4 diffs)

branches/3.2/mindi-busybox/init/mesg.c

@@ -8 +8 @@
  */
 
-//applet:IF_MESG(APPLET(mesg, _BB_DIR_USR_BIN, _BB_SUID_DROP))
-
-//kbuild:lib-$(CONFIG_MESG) += mesg.o
-
 //config:config MESG
 //config:   bool "mesg"
@@ -18 +14 @@
 //config:     Mesg controls access to your terminal by others. It is typically
 //config:     used to allow or disallow other users to write to your terminal
+//config:
+//config:config FEATURE_MESG_ENABLE_ONLY_GROUP
+//config:   bool "Enable writing to tty only by group, not by everybody"
+//config:   default y
+//config:   depends on MESG
+//config:   help
+//config:     Usually, ttys are owned by group "tty", and "write" tool is
+//config:     setgid to this group. This way, "mesg y" only needs to enable
+//config:     "write by owning group" bit in tty mode.
+//config:
+//config:     If you set this option to N, "mesg y" will enable writing
+//config:     by anybody at all. This is not recommended.
+
+//applet:IF_MESG(APPLET(mesg, BB_DIR_USR_BIN, BB_SUID_DROP))
+
+//kbuild:lib-$(CONFIG_MESG) += mesg.o
 
 //usage:#define mesg_trivial_usage
@@ -28 +40 @@
 #include "libbb.h"
 
-#ifdef USE_TTY_GROUP
+#if ENABLE_FEATURE_MESG_ENABLE_ONLY_GROUP
 #define S_IWGRP_OR_S_IWOTH  S_IWGRP
 #else
@@ -38 +50 @@
 {
     struct stat sb;
-    const char *tty;
+    mode_t m;
     char c = 0;
 
     argv++;
 
-    if (!argv[0]
-     || (!argv[1] && ((c = argv[0][0]) == 'y' || c == 'n'))
+    if (argv[0]
+     && (argv[1] || ((c = argv[0][0]) != 'y' && c != 'n'))
     ) {
-        tty = xmalloc_ttyname(STDERR_FILENO);
-        if (tty == NULL) {
-            tty = "ttyname";
-        } else if (stat(tty, &sb) == 0) {
-            mode_t m;
-            if (c == 0) {
-                puts((sb.st_mode & (S_IWGRP|S_IWOTH)) ? "is y" : "is n");
-                return EXIT_SUCCESS;
-            }
-            m = (c == 'y') ? sb.st_mode | S_IWGRP_OR_S_IWOTH
-                           : sb.st_mode & ~(S_IWGRP|S_IWOTH);
-            if (chmod(tty, m) == 0) {
-                return EXIT_SUCCESS;
-            }
-        }
-        bb_simple_perror_msg_and_die(tty);
+        bb_show_usage();
     }
-    bb_show_usage();
+
+    if (!isatty(STDIN_FILENO))
+        bb_error_msg_and_die("not a tty");
+
+    xfstat(STDIN_FILENO, &sb, "stderr");
+    if (c == 0) {
+        puts((sb.st_mode & (S_IWGRP|S_IWOTH)) ? "is y" : "is n");
+        return EXIT_SUCCESS;
+    }
+    m = (c == 'y') ? sb.st_mode | S_IWGRP_OR_S_IWOTH
+                   : sb.st_mode & ~(S_IWGRP|S_IWOTH);
+    if (fchmod(STDIN_FILENO, m) != 0)
+        bb_perror_nomsg_and_die();
+    return EXIT_SUCCESS;
 }