python: module containing ANSI colour sequences

This is going to be used by `samba-tool visualize` and samba_kcc.

Signed-off-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>

diff --git a/python/samba/colour.py b/python/samba/colour.py
new file mode 100644 (file)
index 0000000..4f6cac0
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+++ b/python/samba/colour.py
@@ -0,0 +1,47 @@
+# ANSI codes for 4 bit and xterm-256color
+#
+# Copyright (C) Andrew Bartlett 2018
+#
+# Originally written by Douglas Bagnall
+#
+# 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 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.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+# The 4 bit colours are available as global variables with names like
+# RED, DARK_RED, REV_RED (for red background), and REV_DARK_RED.
+#
+# The 256-colour codes are obtained using xterm_256_color(n), where n
+# is the number of the desired colour.
+
+# C_NORMAL resets to normal, whatever that is
+C_NORMAL = "\033[0m"
+
+UNDERLINE = "\033[4m"
+
+def _gen_ansi_colours():
+    g = globals()
+    for i, name in enumerate(('BLACK', 'RED', 'GREEN', 'YELLOW', 'BLUE',
+                              'MAGENTA', 'CYAN', 'WHITE')):
+        g[name] = "\033[1;3%dm" % i
+        g['DARK_' + name] = "\033[3%dm" % i
+        g['REV_' + name] = "\033[1;4%dm" % i
+        g['REV_DARK_' + name] = "\033[4%dm" % i
+
+_gen_ansi_colours()
+
+
+def xterm_256_colour(n, bg=False, bold=False):
+    weight = '01;' if bold else ''
+    target = '48' if bg else '38'
+
+    return "\033[%s%s;5;%dm" % (weight, target, int(n))