+++ /dev/null
-// Copyright 2015 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
-
-// This program generates the trie for width operations. The generated table
-// includes width category information as well as the normalization mappings.
-package main
-
-import (
- "bytes"
- "fmt"
- "io"
- "log"
- "math"
- "unicode/utf8"
-
- "golang.org/x/text/internal/gen"
- "golang.org/x/text/internal/triegen"
-)
-
-// See gen_common.go for flags.
-
-func main() {
- gen.Init()
- genTables()
- genTests()
- gen.Repackage("gen_trieval.go", "trieval.go", "width")
- gen.Repackage("gen_common.go", "common_test.go", "width")
-}
-
-func genTables() {
- t := triegen.NewTrie("width")
- // fold and inverse mappings. See mapComment for a description of the format
- // of each entry. Add dummy value to make an index of 0 mean no mapping.
- inverse := [][4]byte{{}}
- mapping := map[[4]byte]int{[4]byte{}: 0}
-
- getWidthData(func(r rune, tag elem, alt rune) {
- idx := 0
- if alt != 0 {
- var buf [4]byte
- buf[0] = byte(utf8.EncodeRune(buf[1:], alt))
- s := string(r)
- buf[buf[0]] ^= s[len(s)-1]
- var ok bool
- if idx, ok = mapping[buf]; !ok {
- idx = len(mapping)
- if idx > math.MaxUint8 {
- log.Fatalf("Index %d does not fit in a byte.", idx)
- }
- mapping[buf] = idx
- inverse = append(inverse, buf)
- }
- }
- t.Insert(r, uint64(tag|elem(idx)))
- })
-
- w := &bytes.Buffer{}
- gen.WriteUnicodeVersion(w)
-
- sz, err := t.Gen(w)
- if err != nil {
- log.Fatal(err)
- }
-
- sz += writeMappings(w, inverse)
-
- fmt.Fprintf(w, "// Total table size %d bytes (%dKiB)\n", sz, sz/1024)
-
- gen.WriteGoFile(*outputFile, "width", w.Bytes())
-}
-
-const inverseDataComment = `
-// inverseData contains 4-byte entries of the following format:
-// <length> <modified UTF-8-encoded rune> <0 padding>
-// The last byte of the UTF-8-encoded rune is xor-ed with the last byte of the
-// UTF-8 encoding of the original rune. Mappings often have the following
-// pattern:
-// Ａ -> A (U+FF21 -> U+0041)
-// Ｂ -> B (U+FF22 -> U+0042)
-// ...
-// By xor-ing the last byte the same entry can be shared by many mappings. This
-// reduces the total number of distinct entries by about two thirds.
-// The resulting entry for the aforementioned mappings is
-// { 0x01, 0xE0, 0x00, 0x00 }
-// Using this entry to map U+FF21 (UTF-8 [EF BC A1]), we get
-// E0 ^ A1 = 41.
-// Similarly, for U+FF22 (UTF-8 [EF BC A2]), we get
-// E0 ^ A2 = 42.
-// Note that because of the xor-ing, the byte sequence stored in the entry is
-// not valid UTF-8.`
-
-func writeMappings(w io.Writer, data [][4]byte) int {
- fmt.Fprintln(w, inverseDataComment)
- fmt.Fprintf(w, "var inverseData = [%d][4]byte{\n", len(data))
- for _, x := range data {
- fmt.Fprintf(w, "{ 0x%02x, 0x%02x, 0x%02x, 0x%02x },\n", x[0], x[1], x[2], x[3])
- }
- fmt.Fprintln(w, "}")
- return len(data) * 4
-}
-
-func genTests() {
- w := &bytes.Buffer{}
- fmt.Fprintf(w, "\nvar mapRunes = map[rune]struct{r rune; e elem}{\n")
- getWidthData(func(r rune, tag elem, alt rune) {
- if alt != 0 {
- fmt.Fprintf(w, "\t0x%X: {0x%X, 0x%X},\n", r, alt, tag)
- }
- })
- fmt.Fprintln(w, "}")
- gen.WriteGoFile("runes_test.go", "width", w.Bytes())
-}
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