From e039e689e3c4baefb4b62703429aaf86eef1bd99 Mon Sep 17 00:00:00 2001
From: Bernhard Reutner-Fischer <rep.dot.nop@gmail.com>
Date: Mon, 26 Oct 2009 23:29:03 +0100
Subject: [PATCH] wall: new applet

text	   data	    bss	    dec	    hex	filename
     81	      0	      0	     81	     51	miscutils/wall.o

Signed-off-by: Bernhard Reutner-Fischer <rep.dot.nop@gmail.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
---
 include/applets.h   |  1 +
 include/usage.h     |  8 ++++++++
 miscutils/Config.in |  6 ++++++
 miscutils/Kbuild    |  1 +
 miscutils/wall.c    | 36 ++++++++++++++++++++++++++++++++++++
 scripts/defconfig   |  1 +
 6 files changed, 53 insertions(+)
 create mode 100644 miscutils/wall.c

diff --git a/include/applets.h b/include/applets.h
index 134f21e2f..9683f1ec8 100644
--- a/include/applets.h
+++ b/include/applets.h
@@ -417,6 +417,7 @@ IF_VCONFIG(APPLET(vconfig, _BB_DIR_SBIN, _BB_SUID_DROP))
 IF_VI(APPLET(vi, _BB_DIR_BIN, _BB_SUID_DROP))
 IF_VLOCK(APPLET(vlock, _BB_DIR_USR_BIN, _BB_SUID_REQUIRE))
 IF_VOLNAME(APPLET(volname, _BB_DIR_USR_BIN, _BB_SUID_DROP))
+IF_WALL(APPLET(wall, _BB_DIR_USR_BIN, _BB_SUID_REQUIRE))
 IF_WATCH(APPLET(watch, _BB_DIR_BIN, _BB_SUID_DROP))
 IF_WATCHDOG(APPLET(watchdog, _BB_DIR_SBIN, _BB_SUID_DROP))
 IF_WC(APPLET(wc, _BB_DIR_USR_BIN, _BB_SUID_DROP))
diff --git a/include/usage.h b/include/usage.h
index 93eb2f6ba..72b6acc47 100644
--- a/include/usage.h
+++ b/include/usage.h
@@ -4950,6 +4950,14 @@
 #define volname_full_usage "\n\n" \
        "Show CD volume name of the DEVICE (default /dev/cdrom)"
 
+#define wall_trivial_usage \
+	"[file]"
+#define wall_full_usage "\n\n" \
+	"Write content of file or standard-input to all logged-in users"
+#define wall_sample_usage \
+	"echo foo | wall\n" \
+	"wall ./mymessage"
+
 #define watch_trivial_usage \
        "[-n seconds] [-t] PROG [ARGS]"
 #define watch_full_usage "\n\n" \
diff --git a/miscutils/Config.in b/miscutils/Config.in
index 9b804889b..842f7f9d2 100644
--- a/miscutils/Config.in
+++ b/miscutils/Config.in
@@ -612,6 +612,12 @@ config VOLNAME
 	help
 	  Prints a CD-ROM volume name.
 
+config WALL
+	bool "wall"
+	default n
+	help
+	  Write a message to all users that are logged in.
+
 config WATCHDOG
 	bool "watchdog"
 	default n
diff --git a/miscutils/Kbuild b/miscutils/Kbuild
index d88cb39ac..22a9adb34 100644
--- a/miscutils/Kbuild
+++ b/miscutils/Kbuild
@@ -42,4 +42,5 @@ lib-$(CONFIG_TIME)        += time.o
 lib-$(CONFIG_TIMEOUT)     += timeout.o
 lib-$(CONFIG_TTYSIZE)     += ttysize.o
 lib-$(CONFIG_VOLNAME)     += volname.o
+lib-$(CONFIG_WALL)        += wall.o
 lib-$(CONFIG_WATCHDOG)    += watchdog.o
diff --git a/miscutils/wall.c b/miscutils/wall.c
new file mode 100644
index 000000000..2dbab60b4
--- /dev/null
+++ b/miscutils/wall.c
@@ -0,0 +1,36 @@
+/* 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 tarball for details.
+ */
+
+#include "libbb.h"
+#include <utmp.h>
+
+int wall_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int wall_main(int argc UNUSED_PARAM, char **argv)
+{
+	struct utmp *ut;
+	char *msg;
+	int fd = argv[1] ? xopen(argv[1], O_RDONLY) : STDIN_FILENO;
+
+	msg = xmalloc_read(fd, NULL);
+	if (ENABLE_FEATURE_CLEAN_UP && argv[1])
+		close(fd);
+	setutent();
+	while ((ut = getutent()) != 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) {
+		endutent();
+		free(msg);
+	}
+	return EXIT_SUCCESS;
+}
diff --git a/scripts/defconfig b/scripts/defconfig
index 797f275d1..f8a92d4c3 100644
--- a/scripts/defconfig
+++ b/scripts/defconfig
@@ -638,6 +638,7 @@ CONFIG_TIME=y
 CONFIG_TIMEOUT=y
 CONFIG_TTYSIZE=y
 CONFIG_VOLNAME=y
+CONFIG_WALL=y
 CONFIG_WATCHDOG=y
 
 #