xref: /openbsd/gnu/usr.bin/perl/t/charset_tools.pl (revision 5759b3d2)
1# Tools to aid testing across platforms with different character sets.
2
3$::IS_ASCII  = ord 'A' ==  65;
4$::IS_EBCDIC = ord 'A' == 193;
5
6# The following functions allow tests to work on both EBCDIC and ASCII-ish
7# platforms.  They convert string scalars between the native character set and
8# the set of 256 characters which is usually called Latin1.  However, they
9# will work properly with any character input, not just Latin1.
10
11sub native_to_uni($) {
12    my $string = shift;
13
14    return $string if $::IS_ASCII;
15    my $output = "";
16    for my $i (0 .. length($string) - 1) {
17        $output .= chr(utf8::native_to_unicode(ord(substr($string, $i, 1))));
18    }
19    # Preserve utf8ness of input onto the output, even if it didn't need to be
20    # utf8
21    utf8::upgrade($output) if utf8::is_utf8($string);
22
23    return $output;
24}
25
26sub uni_to_native($) {
27    my $string = shift;
28
29    return $string if $::IS_ASCII;
30    my $output = "";
31    for my $i (0 .. length($string) - 1) {
32        $output .= chr(utf8::unicode_to_native(ord(substr($string, $i, 1))));
33    }
34    # Preserve utf8ness of input onto the output, even if it didn't need to be
35    # utf8
36    utf8::upgrade($output) if utf8::is_utf8($string);
37
38    return $output;
39}
40
41sub byte_utf8a_to_utf8n {
42    # Convert a UTF-8 byte sequence into the platform's native UTF-8
43    # equivalent, currently only UTF-8 and UTF-EBCDIC.
44
45    my @utf8_skip = (
46    # This translates a utf-8-encoded byte into how many bytes the full utf8
47    # character occupies.
48
49      # 0  1  2  3  4  5  6  7  8  9  A  B  C  D  E  F
50        1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  # 0
51        1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  # 1
52        1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  # 2
53        1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  # 3
54        1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  # 4
55        1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  # 5
56        1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  # 6
57        1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  # 7
58       -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,  # 8
59       -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,  # 9
60       -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,  # A
61       -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,  # B
62       -1,-1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,  # C
63        2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,  # D
64        3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,  # E
65        4, 4, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 6, 6, 7,13,  # F
66    );
67
68    my $string = shift;
69    die "Input to byte_utf8a-to_utf8n() must not be flagged UTF-8"
70                                                    if utf8::is_utf8($string);
71    return $string if $::IS_ASCII;
72    die "Expecting ASCII or EBCDIC" unless $::IS_EBCDIC;
73
74    my $length = length($string);
75    #diag($string);
76    #diag($length);
77    my $out = "";
78    for ($i = 0; $i < $length; $i++) {
79        my $byte = ord substr($string, $i, 1);
80        my $byte_count = $utf8_skip[$byte];
81        #diag($byte);
82        #diag($byte_count);
83
84        die "Illegal start byte" if $byte_count < 0;
85        if ($i + $byte_count > $length) {
86            die "Attempt to read " . $i + $byte_count - $length . " beyond end-of-string";
87        }
88
89        # Just translate UTF-8 invariants directly.
90        if ($byte_count == 1) {
91            $out .= chr utf8::unicode_to_native($byte);
92            next;
93        }
94
95        # Otherwise calculate the code point ordinal represented by the
96        # sequence beginning with this byte, using the algorithm adapted from
97        # utf8.c.  We absorb each byte in the sequence as we go along
98        my $ord = $byte & (0x1F >> ($byte_count - 2));
99        my $bytes_remaining = $byte_count - 1;
100        while ($bytes_remaining > 0) {
101            $byte = ord substr($string, ++$i, 1);
102            unless (($byte & 0xC0) == 0x80) {
103                die sprintf "byte '%X' is not a valid continuation", $byte;
104            }
105            $ord = $ord << 6 | ($byte & 0x3f);
106            $bytes_remaining--;
107        }
108        #diag($byte);
109        #diag($ord);
110
111        my $expected_bytes = $ord < 0x80
112                             ? 1
113                             : $ord < 0x800
114                               ? 2
115                               : $ord < 0x10000
116                                 ? 3
117                                 : $ord < 0x200000
118                                   ? 4
119                                   : $ord < 0x4000000
120                                     ? 5
121                                     : $ord < 0x80000000
122                                       ? 6
123                                       : 7;
124                                       #: (uv) < UTF8_QUAD_MAX ? 7 : 13 )
125
126        # Make sure is not an overlong sequence
127        if ($byte_count != $expected_bytes) {
128            die sprintf "character U+%X should occupy %d bytes, not %d",
129                                            $ord, $expected_bytes, $byte_count;
130        }
131
132        # Now that we have found the code point the original UTF-8 meant, we
133        # use the native chr function to get its native string equivalent.
134        $out .= chr utf8::unicode_to_native($ord);
135    }
136
137    utf8::encode($out); # Turn off utf8 flag.
138    #diag($out);
139    return $out;
140}
141
142my @i8_to_native = (    # Only code page 1047 so far.
143# _0   _1   _2   _3   _4   _5   _6   _7   _8   _9   _A   _B   _C   _D   _E   _F
1440x00,0x01,0x02,0x03,0x37,0x2D,0x2E,0x2F,0x16,0x05,0x15,0x0B,0x0C,0x0D,0x0E,0x0F,
1450x10,0x11,0x12,0x13,0x3C,0x3D,0x32,0x26,0x18,0x19,0x3F,0x27,0x1C,0x1D,0x1E,0x1F,
1460x40,0x5A,0x7F,0x7B,0x5B,0x6C,0x50,0x7D,0x4D,0x5D,0x5C,0x4E,0x6B,0x60,0x4B,0x61,
1470xF0,0xF1,0xF2,0xF3,0xF4,0xF5,0xF6,0xF7,0xF8,0xF9,0x7A,0x5E,0x4C,0x7E,0x6E,0x6F,
1480x7C,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,
1490xD7,0xD8,0xD9,0xE2,0xE3,0xE4,0xE5,0xE6,0xE7,0xE8,0xE9,0xAD,0xE0,0xBD,0x5F,0x6D,
1500x79,0x81,0x82,0x83,0x84,0x85,0x86,0x87,0x88,0x89,0x91,0x92,0x93,0x94,0x95,0x96,
1510x97,0x98,0x99,0xA2,0xA3,0xA4,0xA5,0xA6,0xA7,0xA8,0xA9,0xC0,0x4F,0xD0,0xA1,0x07,
1520x20,0x21,0x22,0x23,0x24,0x25,0x06,0x17,0x28,0x29,0x2A,0x2B,0x2C,0x09,0x0A,0x1B,
1530x30,0x31,0x1A,0x33,0x34,0x35,0x36,0x08,0x38,0x39,0x3A,0x3B,0x04,0x14,0x3E,0xFF,
1540x41,0x42,0x43,0x44,0x45,0x46,0x47,0x48,0x49,0x4A,0x51,0x52,0x53,0x54,0x55,0x56,
1550x57,0x58,0x59,0x62,0x63,0x64,0x65,0x66,0x67,0x68,0x69,0x6A,0x70,0x71,0x72,0x73,
1560x74,0x75,0x76,0x77,0x78,0x80,0x8A,0x8B,0x8C,0x8D,0x8E,0x8F,0x90,0x9A,0x9B,0x9C,
1570x9D,0x9E,0x9F,0xA0,0xAA,0xAB,0xAC,0xAE,0xAF,0xB0,0xB1,0xB2,0xB3,0xB4,0xB5,0xB6,
1580xB7,0xB8,0xB9,0xBA,0xBB,0xBC,0xBE,0xBF,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xDA,0xDB,
1590xDC,0xDD,0xDE,0xDF,0xE1,0xEA,0xEB,0xEC,0xED,0xEE,0xEF,0xFA,0xFB,0xFC,0xFD,0xFE,
160);
161
162my @native_to_i8;
163for (my $i = 0; $i < 256; $i++) {
164    $native_to_i8[$i8_to_native[$i]] = $i;
165}
166
167*I8_to_native = ($::IS_ASCII)
168                ? sub { return shift }
169                : sub { return join "", map { chr $i8_to_native[ord $_] }
170                                            split "", shift };
171*native_to_I8 = ($::IS_ASCII)
172                ? sub { return shift }
173                : sub { return join "", map { chr $native_to_i8[ord $_] }
174                                            split "", shift };
175
1761
177