path: root/vendor/golang.org/x/text/encoding/charmap/maketables.go

// Copyright 2013 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

// +build ignore

package main

import (
    "bufio"
    "fmt"
    "log"
    "net/http"
    "sort"
    "strings"
    "unicode/utf8"

    "golang.org/x/text/encoding"
    "golang.org/x/text/internal/gen"
)

const ascii = "\x00\x01\x02\x03\x04\x05\x06\x07\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f" +
    "\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f" +
    ` !"#$%&'()*+,-./0123456789:;<=>?` +
    `@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_` +
    "`abcdefghijklmnopqrstuvwxyz{|}~\u007f"

var encodings = []struct {
    name        string
    mib         string
    comment     string
    varName     string
    replacement byte
    mapping     string
}{
    {
        "IBM Code Page 437",
        "PC8CodePage437",
        "",
        "CodePage437",
        encoding.ASCIISub,
        "http://source.icu-project.org/repos/icu/data/trunk/charset/data/ucm/glibc-IBM437-2.1.2.ucm",
    },
    {
        "IBM Code Page 850",
        "PC850Multilingual",
        "",
        "CodePage850",
        encoding.ASCIISub,
        "http://source.icu-project.org/repos/icu/data/trunk/charset/data/ucm/glibc-IBM850-2.1.2.ucm",
    },
    {
        "IBM Code Page 852",
        "PCp852",
        "",
        "CodePage852",
        encoding.ASCIISub,
        "http://source.icu-project.org/repos/icu/data/trunk/charset/data/ucm/glibc-IBM852-2.1.2.ucm",
    },
    {
        "IBM Code Page 855",
        "IBM855",
        "",
        "CodePage855",
        encoding.ASCIISub,
        "http://source.icu-project.org/repos/icu/data/trunk/charset/data/ucm/glibc-IBM855-2.1.2.ucm",
    },
    {
        "Windows Code Page 858", // PC latin1 with Euro
        "IBM00858",
        "",
        "CodePage858",
        encoding.ASCIISub,
        "http://source.icu-project.org/repos/icu/data/trunk/charset/data/ucm/windows-858-2000.ucm",
    },
    {
        "IBM Code Page 860",
        "IBM860",
        "",
        "CodePage860",
        encoding.ASCIISub,
        "http://source.icu-project.org/repos/icu/data/trunk/charset/data/ucm/glibc-IBM860-2.1.2.ucm",
    },
    {
        "IBM Code Page 862",
        "PC862LatinHebrew",
        "",
        "CodePage862",
        encoding.ASCIISub,
        "http://source.icu-project.org/repos/icu/data/trunk/charset/data/ucm/glibc-IBM862-2.1.2.ucm",
    },
    {
        "IBM Code Page 863",
        "IBM863",
        "",
        "CodePage863",
        encoding.ASCIISub,
        "http://source.icu-project.org/repos/icu/data/trunk/charset/data/ucm/glibc-IBM863-2.1.2.ucm",
    },
    {
        "IBM Code Page 865",
        "IBM865",
        "",
        "CodePage865",
        encoding.ASCIISub,
        "http://source.icu-project.org/repos/icu/data/trunk/charset/data/ucm/glibc-IBM865-2.1.2.ucm",
    },
    {
        "IBM Code Page 866",
        "IBM866",
        "",
        "CodePage866",
        encoding.ASCIISub,
        "http://encoding.spec.whatwg.org/index-ibm866.txt",
    },
    {
        "ISO 8859-1",
        "ISOLatin1",
        "",
        "ISO8859_1",
        encoding.ASCIISub,
        "http://source.icu-project.org/repos/icu/data/trunk/charset/data/ucm/iso-8859_1-1998.ucm",
    },
    {
        "ISO 8859-2",
        "ISOLatin2",
        "",
        "ISO8859_2",
        encoding.ASCIISub,
        "http://encoding.spec.whatwg.org/index-iso-8859-2.txt",
    },
    {
        "ISO 8859-3",
        "ISOLatin3",
        "",
        "ISO8859_3",
        encoding.ASCIISub,
        "http://encoding.spec.whatwg.org/index-iso-8859-3.txt",
    },
    {
        "ISO 8859-4",
        "ISOLatin4",
        "",
        "ISO8859_4",
        encoding.ASCIISub,
        "http://encoding.spec.whatwg.org/index-iso-8859-4.txt",
    },
    {
        "ISO 8859-5",
        "ISOLatinCyrillic",
        "",
        "ISO8859_5",
        encoding.ASCIISub,
        "http://encoding.spec.whatwg.org/index-iso-8859-5.txt",
    },
    {
        "ISO 8859-6",
        "ISOLatinArabic",
        "",
        "ISO8859_6,ISO8859_6E,ISO8859_6I",
        encoding.ASCIISub,
        "http://encoding.spec.whatwg.org/index-iso-8859-6.txt",
    },
    {
        "ISO 8859-7",
        "ISOLatinGreek",
        "",
        "ISO8859_7",
        encoding.ASCIISub,
        "http://encoding.spec.whatwg.org/index-iso-8859-7.txt",
    },
    {
        "ISO 8859-8",
        "ISOLatinHebrew",
        "",
        "ISO8859_8,ISO8859_8E,ISO8859_8I",
        encoding.ASCIISub,
        "http://encoding.spec.whatwg.org/index-iso-8859-8.txt",
    },
    {
        "ISO 8859-10",
        "ISOLatin6",
        "",
        "ISO8859_10",
        encoding.ASCIISub,
        "http://encoding.spec.whatwg.org/index-iso-8859-10.txt",
    },
    {
        "ISO 8859-13",
        "ISO885913",
        "",
        "ISO8859_13",
        encoding.ASCIISub,
        "http://encoding.spec.whatwg.org/index-iso-8859-13.txt",
    },
    {
        "ISO 8859-14",
        "ISO885914",
        "",
        "ISO8859_14",
        encoding.ASCIISub,
        "http://encoding.spec.whatwg.org/index-iso-8859-14.txt",
    },
    {
        "ISO 8859-15",
        "ISO885915",
        "",
        "ISO8859_15",
        encoding.ASCIISub,
        "http://encoding.spec.whatwg.org/index-iso-8859-15.txt",
    },
    {
        "ISO 8859-16",
        "ISO885916",
        "",
        "ISO8859_16",
        encoding.ASCIISub,
        "http://encoding.spec.whatwg.org/index-iso-8859-16.txt",
    },
    {
        "KOI8-R",
        "KOI8R",
        "",
        "KOI8R",
        encoding.ASCIISub,
        "http://encoding.spec.whatwg.org/index-koi8-r.txt",
    },
    {
        "KOI8-U",
        "KOI8U",
        "",
        "KOI8U",
        encoding.ASCIISub,
        "http://encoding.spec.whatwg.org/index-koi8-u.txt",
    },
    {
        "Macintosh",
        "Macintosh",
        "",
        "Macintosh",
        encoding.ASCIISub,
        "http://encoding.spec.whatwg.org/index-macintosh.txt",
    },
    {
        "Macintosh Cyrillic",
        "MacintoshCyrillic",
        "",
        "MacintoshCyrillic",
        encoding.ASCIISub,
        "http://encoding.spec.whatwg.org/index-x-mac-cyrillic.txt",
    },
    {
        "Windows 874",
        "Windows874",
        "",
        "Windows874",
        encoding.ASCIISub,
        "http://encoding.spec.whatwg.org/index-windows-874.txt",
    },
    {
        "Windows 1250",
        "Windows1250",
        "",
        "Windows1250",
        encoding.ASCIISub,
        "http://encoding.spec.whatwg.org/index-windows-1250.txt",
    },
    {
        "Windows 1251",
        "Windows1251",
        "",
        "Windows1251",
        encoding.ASCIISub,
        "http://encoding.spec.whatwg.org/index-windows-1251.txt",
    },
    {
        "Windows 1252",
        "Windows1252",
        "",
        "Windows1252",
        encoding.ASCIISub,
        "http://encoding.spec.whatwg.org/index-windows-1252.txt",
    },
    {
        "Windows 1253",
        "Windows1253",
        "",
        "Windows1253",
        encoding.ASCIISub,
        "http://encoding.spec.whatwg.org/index-windows-1253.txt",
    },
    {
        "Windows 1254",
        "Windows1254",
        "",
        "Windows1254",
        encoding.ASCIISub,
        "http://encoding.spec.whatwg.org/index-windows-1254.txt",
    },
    {
        "Windows 1255",
        "Windows1255",
        "",
        "Windows1255",
        encoding.ASCIISub,
        "http://encoding.spec.whatwg.org/index-windows-1255.txt",
    },
    {
        "Windows 1256",
        "Windows1256",
        "",
        "Windows1256",
        encoding.ASCIISub,
        "http://encoding.spec.whatwg.org/index-windows-1256.txt",
    },
    {
        "Windows 1257",
        "Windows1257",
        "",
        "Windows1257",
        encoding.ASCIISub,
        "http://encoding.spec.whatwg.org/index-windows-1257.txt",
    },
    {
        "Windows 1258",
        "Windows1258",
        "",
        "Windows1258",
        encoding.ASCIISub,
        "http://encoding.spec.whatwg.org/index-windows-1258.txt",
    },
    {
        "X-User-Defined",
        "XUserDefined",
        "It is defined at http://encoding.spec.whatwg.org/#x-user-defined",
        "XUserDefined",
        encoding.ASCIISub,
        ascii +
            "\uf780\uf781\uf782\uf783\uf784\uf785\uf786\uf787" +
            "\uf788\uf789\uf78a\uf78b\uf78c\uf78d\uf78e\uf78f" +
            "\uf790\uf791\uf792\uf793\uf794\uf795\uf796\uf797" +
            "\uf798\uf799\uf79a\uf79b\uf79c\uf79d\uf79e\uf79f" +
            "\uf7a0\uf7a1\uf7a2\uf7a3\uf7a4\uf7a5\uf7a6\uf7a7" +
            "\uf7a8\uf7a9\uf7aa\uf7ab\uf7ac\uf7ad\uf7ae\uf7af" +
            "\uf7b0\uf7b1\uf7b2\uf7b3\uf7b4\uf7b5\uf7b6\uf7b7" +
            "\uf7b8\uf7b9\uf7ba\uf7bb\uf7bc\uf7bd\uf7be\uf7bf" +
            "\uf7c0\uf7c1\uf7c2\uf7c3\uf7c4\uf7c5\uf7c6\uf7c7" +
            "\uf7c8\uf7c9\uf7ca\uf7cb\uf7cc\uf7cd\uf7ce\uf7cf" +
            "\uf7d0\uf7d1\uf7d2\uf7d3\uf7d4\uf7d5\uf7d6\uf7d7" +
            "\uf7d8\uf7d9\uf7da\uf7db\uf7dc\uf7dd\uf7de\uf7df" +
            "\uf7e0\uf7e1\uf7e2\uf7e3\uf7e4\uf7e5\uf7e6\uf7e7" +
            "\uf7e8\uf7e9\uf7ea\uf7eb\uf7ec\uf7ed\uf7ee\uf7ef" +
            "\uf7f0\uf7f1\uf7f2\uf7f3\uf7f4\uf7f5\uf7f6\uf7f7" +
            "\uf7f8\uf7f9\uf7fa\uf7fb\uf7fc\uf7fd\uf7fe\uf7ff",
    },
}

func getWHATWG(url string) string {
    res, err := http.Get(url)
    if err != nil {
        log.Fatalf("%q: Get: %v", url, err)
    }
    defer res.Body.Close()

    mapping := make([]rune, 128)
    for i := range mapping {
        mapping[i] = '\ufffd'
    }

    scanner := bufio.NewScanner(res.Body)
    for scanner.Scan() {
        s := strings.TrimSpace(scanner.Text())
        if s == "" || s[0] == '#' {
            continue
        }
        x, y := 0, 0
        if _, err := fmt.Sscanf(s, "%d\t0x%x", &x, &y); err != nil {
            log.Fatalf("could not parse %q", s)
        }
        if x < 0 || 128 <= x {
            log.Fatalf("code %d is out of range", x)
        }
        if 0x80 <= y && y < 0xa0 {
            // We diverge from the WHATWG spec by mapping control characters
            // in the range [0x80, 0xa0) to U+FFFD.
            continue
        }
        mapping[x] = rune(y)
    }
    return ascii + string(mapping)
}

func getUCM(url string) string {
    res, err := http.Get(url)
    if err != nil {
        log.Fatalf("%q: Get: %v", url, err)
    }
    defer res.Body.Close()

    mapping := make([]rune, 256)
    for i := range mapping {
        mapping[i] = '\ufffd'
    }

    charsFound := 0
    scanner := bufio.NewScanner(res.Body)
    for scanner.Scan() {
        s := strings.TrimSpace(scanner.Text())
        if s == "" || s[0] == '#' {
            continue
        }
        var c byte
        var r rune
        if _, err := fmt.Sscanf(s, `<U%x> \x%x |0`, &r, &c); err != nil {
            continue
        }
        mapping[c] = r
        charsFound++
    }

    if charsFound < 200 {
        log.Fatalf("%q: only %d characters found (wrong page format?)", url, charsFound)
    }

    return string(mapping)
}

func main() {
    mibs := map[string]bool{}
    all := []string{}

    w := gen.NewCodeWriter()
    defer w.WriteGoFile("tables.go", "charmap")

    printf := func(s string, a ...interface{}) { fmt.Fprintf(w, s, a...) }

    printf("import (\n")
    printf("\t\"golang.org/x/text/encoding\"\n")
    printf("\t\"golang.org/x/text/encoding/internal/identifier\"\n")
    printf(")\n\n")
    for _, e := range encodings {
        varNames := strings.Split(e.varName, ",")
        all = append(all, varNames...)
        varName := varNames[0]
        switch {
        case strings.HasPrefix(e.mapping, "http://encoding.spec.whatwg.org/"):
            e.mapping = getWHATWG(e.mapping)
        case strings.HasPrefix(e.mapping, "http://source.icu-project.org/repos/icu/data/trunk/charset/data/ucm/"):
            e.mapping = getUCM(e.mapping)
        }

        asciiSuperset, low := strings.HasPrefix(e.mapping, ascii), 0x00
        if asciiSuperset {
            low = 0x80
        }
        lvn := 1
        if strings.HasPrefix(varName, "ISO") || strings.HasPrefix(varName, "KOI") {
            lvn = 3
        }
        lowerVarName := strings.ToLower(varName[:lvn]) + varName[lvn:]
        printf("// %s is the %s encoding.\n", varName, e.name)
        if e.comment != "" {
            printf("//\n// %s\n", e.comment)
        }
        printf("var %s encoding.Encoding = &%s\n\nvar %s = charmap{\nname: %q,\n",
            varName, lowerVarName, lowerVarName, e.name)
        if mibs[e.mib] {
            log.Fatalf("MIB type %q declared multiple times.", e.mib)
        }
        printf("mib: identifier.%s,\n", e.mib)
        printf("asciiSuperset: %t,\n", asciiSuperset)
        printf("low: 0x%02x,\n", low)
        printf("replacement: 0x%02x,\n", e.replacement)

        printf("decode: [256]utf8Enc{\n")
        i, backMapping := 0, map[rune]byte{}
        for _, c := range e.mapping {
            if _, ok := backMapping[c]; !ok && c != utf8.RuneError {
                backMapping[c] = byte(i)
            }
            var buf [8]byte
            n := utf8.EncodeRune(buf[:], c)
            if n > 3 {
                panic(fmt.Sprintf("rune %q (%U) is too long", c, c))
            }
            printf("{%d,[3]byte{0x%02x,0x%02x,0x%02x}},", n, buf[0], buf[1], buf[2])
            if i%2 == 1 {
                printf("\n")
            }
            i++
        }
        printf("},\n")

        printf("encode: [256]uint32{\n")
        encode := make([]uint32, 0, 256)
        for c, i := range backMapping {
            encode = append(encode, uint32(i)<<24|uint32(c))
        }
        sort.Sort(byRune(encode))
        for len(encode) < cap(encode) {
            encode = append(encode, encode[len(encode)-1])
        }
        for i, enc := range encode {
            printf("0x%08x,", enc)
            if i%8 == 7 {
                printf("\n")
            }
        }
        printf("},\n}\n")

        // Add an estimate of the size of a single charmap{} struct value, which
        // includes two 256 elem arrays of 4 bytes and some extra fields, which
        // align to 3 uint64s on 64-bit architectures.
        w.Size += 2*4*256 + 3*8
    }
    // TODO: add proper line breaking.
    printf("var listAll = []encoding.Encoding{\n%s,\n}\n\n", strings.Join(all, ",\n"))
}

type byRune []uint32

func (b byRune) Len() int           { return len(b) }
func (b byRune) Less(i, j int) bool { return b[i]&0xffffff < b[j]&0xffffff }
func (b byRune) Swap(i, j int)      { b[i], b[j] = b[j], b[i] }