1 files changed, 63 insertions, 0 deletions

diff --git a/util-linux/wall.c b/util-linux/wall.c
new file mode 100644
index 000000000..50658f457
--- /dev/null
+++ b/util-linux/wall.c
@@ -0,0 +1,63 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * wall - write a message to all logged-in users
+ * Copyright (c) 2009 Bernhard Reutner-Fischer
+ *
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
+ */
+
+//config:config WALL
+//config:       bool "wall"
+//config:       default y
+//config:       depends on FEATURE_UTMP
+//config:       help
+//config:         Write a message to all users that are logged in.
+
+/* Needs to be run by root or be suid root - needs to write to /dev/TTY: */
+//applet:IF_WALL(APPLET(wall, BB_DIR_USR_BIN, BB_SUID_REQUIRE))
+
+//kbuild:lib-$(CONFIG_WALL) += wall.o
+
+//usage:#define wall_trivial_usage
+//usage:        "[FILE]"
+//usage:#define wall_full_usage "\n\n"
+//usage:        "Write content of FILE or stdin to all logged-in users"
+//usage:
+//usage:#define wall_sample_usage
+//usage:        "echo foo | wall\n"
+//usage:        "wall ./mymessage"
+
+#include "libbb.h"
+
+int wall_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int wall_main(int argc UNUSED_PARAM, char **argv)
+{
+        struct utmpx *ut;
+        char *msg;
+        int fd;
+
+        fd = STDIN_FILENO;
+        if (argv[1]) {
+                /* The applet is setuid.
+                 * Access to the file must be under user's uid/gid.
+                 */
+                fd = xopen_as_uid_gid(argv[1], O_RDONLY, getuid(), getgid());
+        }
+        msg = xmalloc_read(fd, NULL);
+        if (ENABLE_FEATURE_CLEAN_UP && argv[1])
+                close(fd);
+        setutxent();
+        while ((ut = getutxent()) != NULL) {
+                char *line;
+                if (ut->ut_type != USER_PROCESS)
+                        continue;
+                line = concat_path_file("/dev", ut->ut_line);
+                xopen_xwrite_close(line, msg);
+                free(line);
+        }
+        if (ENABLE_FEATURE_CLEAN_UP) {
+                endutxent();
+                free(msg);
+        }
+        return EXIT_SUCCESS;
+}