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diff --git a/src/libsystemd-terminal/term-charset.c b/src/libsystemd-terminal/term-charset.c
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+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+ This file is part of systemd.
+
+ Copyright (C) 2014 David Herrmann <dh.herrmann@gmail.com>
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+/*
+ * VTE Character Sets
+ * These are predefined charactersets that can be loaded into GL and GR. By
+ * default we use unicode_lower and unicode_upper, that is, both sets have the
+ * exact unicode mapping. unicode_lower is effectively ASCII and unicode_upper
+ * as defined by the unicode standard (I guess, ISO 8859-1).
+ * Several other character sets are defined here. However, all of them are
+ * limited to the 96 character space of GL or GR. Everything beyond GR (which
+ * was not supported by the classic VTs by DEC but is available in VT emulators
+ * that support unicode/UTF8) is always mapped to unicode and cannot be changed
+ * by these character sets. Even mapping GL and GR is only available for
+ * backwards compatibility as new applications can use the Unicode functionality
+ * of the VTE.
+ *
+ * Moreover, mapping GR is almost unnecessary to support. In fact, Unicode UTF-8
+ * support in VTE works by reading every incoming data as UTF-8 stream. This
+ * maps GL/ASCII to ASCII, as UTF-8 is backwards compatible to ASCII, however,
+ * everything that has the 8th bit set is a >=2-byte haracter in UTF-8. That is,
+ * this is in no way backwards compatible to >=VT220 8bit support. Therefore, if
+ * someone maps a character set into GR and wants to use them with this VTE,
+ * then they must already send UTF-8 characters to use GR (all GR characters are
+ * 8-bits). Hence, they can easily also send the correct UTF-8 character for the
+ * unicode mapping.
+ * The only advantage is that most characters in many sets are 3-byte UTF-8
+ * characters and by mapping the set into GR/GL you can use 2 or 1 byte UTF-8
+ * characters which saves bandwidth.
+ * Another reason is, if you have older applications that use the VT220 8-bit
+ * support and you put a ASCII/8bit-extension to UTF-8 converter in between, you
+ * need these mappings to have the application behave correctly if it uses GL/GR
+ * mappings extensively.
+ *
+ * Anyway, we support GL/GR mappings so here are the most commonly used maps as
+ * defined by Unicode-standard, DEC-private maps and other famous charmaps.
+ *
+ * Characters 1-32 are always the control characters (part of CL) and cannot be
+ * mapped. Characters 34-127 (94 characters) are part of GL and can be mapped.
+ * Characters 33 and 128 are not part of GL and always mapped by the VTE.
+ * However, for GR they can be mapped differently (96 chars) so we have to
+ * include them. The mapper has to take care not to use them in GL.
+ */
+
+#include <errno.h>
+#include <stdlib.h>
+#include <string.h>
+#include "term-internal.h"
+
+/*
+ * Lower Unicode character set. This maps the characters to the basic ASCII
+ * characters 33-126. These are all graphics characters defined in ASCII.
+ */
+term_charset term_unicode_lower = {
+ [0] = 32,
+ [1] = 33,
+ [2] = 34,
+ [3] = 35,
+ [4] = 36,
+ [5] = 37,
+ [6] = 38,
+ [7] = 39,
+ [8] = 40,
+ [9] = 41,
+ [10] = 42,
+ [11] = 43,
+ [12] = 44,
+ [13] = 45,
+ [14] = 46,
+ [15] = 47,
+ [16] = 48,
+ [17] = 49,
+ [18] = 50,
+ [19] = 51,
+ [20] = 52,
+ [21] = 53,
+ [22] = 54,
+ [23] = 55,
+ [24] = 56,
+ [25] = 57,
+ [26] = 58,
+ [27] = 59,
+ [28] = 60,
+ [29] = 61,
+ [30] = 62,
+ [31] = 63,
+ [32] = 64,
+ [33] = 65,
+ [34] = 66,
+ [35] = 67,
+ [36] = 68,
+ [37] = 69,
+ [38] = 70,
+ [39] = 71,
+ [40] = 72,
+ [41] = 73,
+ [42] = 74,
+ [43] = 75,
+ [44] = 76,
+ [45] = 77,
+ [46] = 78,
+ [47] = 79,
+ [48] = 80,
+ [49] = 81,
+ [50] = 82,
+ [51] = 83,
+ [52] = 84,
+ [53] = 85,
+ [54] = 86,
+ [55] = 87,
+ [56] = 88,
+ [57] = 89,
+ [58] = 90,
+ [59] = 91,
+ [60] = 92,
+ [61] = 93,
+ [62] = 94,
+ [63] = 95,
+ [64] = 96,
+ [65] = 97,
+ [66] = 98,
+ [67] = 99,
+ [68] = 100,
+ [69] = 101,
+ [70] = 102,
+ [71] = 103,
+ [72] = 104,
+ [73] = 105,
+ [74] = 106,
+ [75] = 107,
+ [76] = 108,
+ [77] = 109,
+ [78] = 110,
+ [79] = 111,
+ [80] = 112,
+ [81] = 113,
+ [82] = 114,
+ [83] = 115,
+ [84] = 116,
+ [85] = 117,
+ [86] = 118,
+ [87] = 119,
+ [88] = 120,
+ [89] = 121,
+ [90] = 122,
+ [91] = 123,
+ [92] = 124,
+ [93] = 125,
+ [94] = 126,
+ [95] = 127,
+};
+
+/*
+ * Upper Unicode Table
+ * This maps all characters to the upper unicode characters 161-254. These are
+ * not compatible to any older 8 bit character sets. See the Unicode standard
+ * for the definitions of each symbol.
+ */
+term_charset term_unicode_upper = {
+ [0] = 160,
+ [1] = 161,
+ [2] = 162,
+ [3] = 163,
+ [4] = 164,
+ [5] = 165,
+ [6] = 166,
+ [7] = 167,
+ [8] = 168,
+ [9] = 169,
+ [10] = 170,
+ [11] = 171,
+ [12] = 172,
+ [13] = 173,
+ [14] = 174,
+ [15] = 175,
+ [16] = 176,
+ [17] = 177,
+ [18] = 178,
+ [19] = 179,
+ [20] = 180,
+ [21] = 181,
+ [22] = 182,
+ [23] = 183,
+ [24] = 184,
+ [25] = 185,
+ [26] = 186,
+ [27] = 187,
+ [28] = 188,
+ [29] = 189,
+ [30] = 190,
+ [31] = 191,
+ [32] = 192,
+ [33] = 193,
+ [34] = 194,
+ [35] = 195,
+ [36] = 196,
+ [37] = 197,
+ [38] = 198,
+ [39] = 199,
+ [40] = 200,
+ [41] = 201,
+ [42] = 202,
+ [43] = 203,
+ [44] = 204,
+ [45] = 205,
+ [46] = 206,
+ [47] = 207,
+ [48] = 208,
+ [49] = 209,
+ [50] = 210,
+ [51] = 211,
+ [52] = 212,
+ [53] = 213,
+ [54] = 214,
+ [55] = 215,
+ [56] = 216,
+ [57] = 217,
+ [58] = 218,
+ [59] = 219,
+ [60] = 220,
+ [61] = 221,
+ [62] = 222,
+ [63] = 223,
+ [64] = 224,
+ [65] = 225,
+ [66] = 226,
+ [67] = 227,
+ [68] = 228,
+ [69] = 229,
+ [70] = 230,
+ [71] = 231,
+ [72] = 232,
+ [73] = 233,
+ [74] = 234,
+ [75] = 235,
+ [76] = 236,
+ [77] = 237,
+ [78] = 238,
+ [79] = 239,
+ [80] = 240,
+ [81] = 241,
+ [82] = 242,
+ [83] = 243,
+ [84] = 244,
+ [85] = 245,
+ [86] = 246,
+ [87] = 247,
+ [88] = 248,
+ [89] = 249,
+ [90] = 250,
+ [91] = 251,
+ [92] = 252,
+ [93] = 253,
+ [94] = 254,
+ [95] = 255,
+};
+
+/*
+ * The DEC supplemental graphics set. For its definition see here:
+ * http://vt100.net/docs/vt220-rm/table2-3b.html
+ * Its basically a mixture of common European symbols that are not part of
+ * ASCII. Most often, this is mapped into GR to extend the basci ASCII part.
+ *
+ * This is very similar to unicode_upper, however, few symbols differ so do not
+ * mix them up!
+ */
+term_charset term_dec_supplemental_graphics = {
+ [0] = -1, /* undefined */
+ [1] = 161,
+ [2] = 162,
+ [3] = 163,
+ [4] = 0,
+ [5] = 165,
+ [6] = 0,
+ [7] = 167,
+ [8] = 164,
+ [9] = 169,
+ [10] = 170,
+ [11] = 171,
+ [12] = 0,
+ [13] = 0,
+ [14] = 0,
+ [15] = 0,
+ [16] = 176,
+ [17] = 177,
+ [18] = 178,
+ [19] = 179,
+ [20] = 0,
+ [21] = 181,
+ [22] = 182,
+ [23] = 183,
+ [24] = 0,
+ [25] = 185,
+ [26] = 186,
+ [27] = 187,
+ [28] = 188,
+ [29] = 189,
+ [30] = 0,
+ [31] = 191,
+ [32] = 192,
+ [33] = 193,
+ [34] = 194,
+ [35] = 195,
+ [36] = 196,
+ [37] = 197,
+ [38] = 198,
+ [39] = 199,
+ [40] = 200,
+ [41] = 201,
+ [42] = 202,
+ [43] = 203,
+ [44] = 204,
+ [45] = 205,
+ [46] = 206,
+ [47] = 207,
+ [48] = 0,
+ [49] = 209,
+ [50] = 210,
+ [51] = 211,
+ [52] = 212,
+ [53] = 213,
+ [54] = 214,
+ [55] = 338,
+ [56] = 216,
+ [57] = 217,
+ [58] = 218,
+ [59] = 219,
+ [60] = 220,
+ [61] = 376,
+ [62] = 0,
+ [63] = 223,
+ [64] = 224,
+ [65] = 225,
+ [66] = 226,
+ [67] = 227,
+ [68] = 228,
+ [69] = 229,
+ [70] = 230,
+ [71] = 231,
+ [72] = 232,
+ [73] = 233,
+ [74] = 234,
+ [75] = 235,
+ [76] = 236,
+ [77] = 237,
+ [78] = 238,
+ [79] = 239,
+ [80] = 0,
+ [81] = 241,
+ [82] = 242,
+ [83] = 243,
+ [84] = 244,
+ [85] = 245,
+ [86] = 246,
+ [87] = 339,
+ [88] = 248,
+ [89] = 249,
+ [90] = 250,
+ [91] = 251,
+ [92] = 252,
+ [93] = 255,
+ [94] = 0,
+ [95] = -1, /* undefined */
+};
+
+/*
+ * DEC special graphics character set. See here for its definition:
+ * http://vt100.net/docs/vt220-rm/table2-4.html
+ * This contains several characters to create ASCII drawings and similar. Its
+ * commonly mapped into GR to extend the basic ASCII characters.
+ *
+ * Lower 62 characters map to ASCII 33-64, everything beyond is special and
+ * commonly used for ASCII drawings. It depends on the Unicode Standard 3.2 for
+ * the extended horizontal scan-line characters 3, 5, 7, and 9.
+ */
+term_charset term_dec_special_graphics = {
+ [0] = -1, /* undefined */
+ [1] = 33,
+ [2] = 34,
+ [3] = 35,
+ [4] = 36,
+ [5] = 37,
+ [6] = 38,
+ [7] = 39,
+ [8] = 40,
+ [9] = 41,
+ [10] = 42,
+ [11] = 43,
+ [12] = 44,
+ [13] = 45,
+ [14] = 46,
+ [15] = 47,
+ [16] = 48,
+ [17] = 49,
+ [18] = 50,
+ [19] = 51,
+ [20] = 52,
+ [21] = 53,
+ [22] = 54,
+ [23] = 55,
+ [24] = 56,
+ [25] = 57,
+ [26] = 58,
+ [27] = 59,
+ [28] = 60,
+ [29] = 61,
+ [30] = 62,
+ [31] = 63,
+ [32] = 64,
+ [33] = 65,
+ [34] = 66,
+ [35] = 67,
+ [36] = 68,
+ [37] = 69,
+ [38] = 70,
+ [39] = 71,
+ [40] = 72,
+ [41] = 73,
+ [42] = 74,
+ [43] = 75,
+ [44] = 76,
+ [45] = 77,
+ [46] = 78,
+ [47] = 79,
+ [48] = 80,
+ [49] = 81,
+ [50] = 82,
+ [51] = 83,
+ [52] = 84,
+ [53] = 85,
+ [54] = 86,
+ [55] = 87,
+ [56] = 88,
+ [57] = 89,
+ [58] = 90,
+ [59] = 91,
+ [60] = 92,
+ [61] = 93,
+ [62] = 94,
+ [63] = 0,
+ [64] = 9830,
+ [65] = 9618,
+ [66] = 9225,
+ [67] = 9228,
+ [68] = 9229,
+ [69] = 9226,
+ [70] = 176,
+ [71] = 177,
+ [72] = 9252,
+ [73] = 9227,
+ [74] = 9496,
+ [75] = 9488,
+ [76] = 9484,
+ [77] = 9492,
+ [78] = 9532,
+ [79] = 9146,
+ [80] = 9147,
+ [81] = 9472,
+ [82] = 9148,
+ [83] = 9149,
+ [84] = 9500,
+ [85] = 9508,
+ [86] = 9524,
+ [87] = 9516,
+ [88] = 9474,
+ [89] = 8804,
+ [90] = 8805,
+ [91] = 960,
+ [92] = 8800,
+ [93] = 163,
+ [94] = 8901,
+ [95] = -1, /* undefined */
+};
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