Add console module

All IO to the console should go through this module from now on.
Read the LDoc comments for details.

Signed-off-by: Tobias Ulmer <tu@emlix.com>

diff --git a/generic/Makefile b/generic/Makefile
index 0c705e5ec0a8cc6af923aba1207fbdf2f31969c2..cf7ccf7a0fc6036f8682792ed1c51153050e030c 100644 (file)
--- a/generic/Makefile
+++ b/generic/Makefile
@@ -29,7 +29,7 @@ TOPLEVEL = ..
 
 include $(TOPLEVEL)/make.vars
 
-LUA_LIBS = strict.lua plugin.lua e2lib.lua
+LUA_LIBS = strict.lua plugin.lua e2lib.lua console.lua
 LUA_LIBS += e2option.lua hash.lua tools.lua transport.lua cache.lua url.lua
 LUA_LIBS += generic_git.lua eio.lua err.lua lock.lua errno.lua trace.lua
 SO_LIBS = lsha1.so leio.so le2lib.so

diff --git a/generic/console.lua b/generic/console.lua
new file mode 100644 (file)
index 0000000..976991c
--- /dev/null
+++ b/generic/console.lua
@@ -0,0 +1,98 @@
+--- Console output. When e2factory acts as a command-line program, this
+-- is just a wrapper for the stdout and stderr channels. This module should make
+-- it easy to extend and redirect console output for other purposes.
+-- @module generic.console
+
+-- Copyright (C) 2013 emlix GmbH, see file AUTHORS
+--
+-- This file is part of e2factory, the emlix embedded build system.
+-- For more information see http://www.e2factory.org
+--
+-- e2factory is a registered trademark of emlix GmbH.
+--
+-- e2factory 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 3 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.
+
+local console = {}
+package.loaded["console"] = console -- prevent module loading loop
+
+local eio = require("eio")
+local strict = require("strict")
+
+local stdout = false
+local stderr = false
+
+--- Open and set up standard and error output to the console.
+function console.open()
+    local rc, re
+
+    rc, re = eio.fdopen(eio.STDERR, "w")
+    if rc then
+        stderr = rc
+    end
+
+    rc, re = eio.fdopen(eio.STDOUT, "w")
+    if rc then
+        stdout = rc
+    end
+end
+
+--- Close console outputs, if appropriate.
+function console.close()
+    -- didn't open stdout and stderr, don't close them.
+end
+
+--- Write message to the standard output channel.
+-- @param msg Message string.
+function console.info(msg)
+    if stdout then
+        eio.fwrite(stdout, msg)
+    else
+        io.stdout:write(msg)
+    end
+end
+
+--- Write message to the error output channel.
+-- @param msg Error message string.
+function console.eout(msg)
+    if stderr then
+        eio.fwrite(stderr, msg)
+    else
+        io.stderr:write(msg)
+    end
+end
+
+--- Write message to the standard output channel, and append a newline.
+-- @param msg Message string, may be nil.
+function console.infonl(msg)
+    msg = msg or ""
+    return console.info(msg.."\n")
+end
+
+--- Pass format string and arguments to string.format() before sending the
+-- resulting string to the standard output channel.
+-- @param format string.format() compatible format.
+-- @param ... Arguments as per format string above.
+function console.infof(format, ...)
+    return console.info(string.format(format, ...))
+end
+
+
+--- Pass format string and arguments to string.format() before sending the
+-- resulting string to the error output channel.
+-- @param format string.format() compatible format.
+-- @param ... Arguments as per format string above.
+function console.eoutf(format, ...)
+    return console.eout(string.format(format, ...))
+end
+
+return strict.lock(console)
+
+-- vim:sw=4:sts=4:et: