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Diffstat (limited to 'vendor/golang.org/x/text/encoding/traditionalchinese/maketables.go')
-rw-r--r--vendor/golang.org/x/text/encoding/traditionalchinese/maketables.go140
1 files changed, 140 insertions, 0 deletions
diff --git a/vendor/golang.org/x/text/encoding/traditionalchinese/maketables.go b/vendor/golang.org/x/text/encoding/traditionalchinese/maketables.go
new file mode 100644
index 000000000..cf7fdb31a
--- /dev/null
+++ b/vendor/golang.org/x/text/encoding/traditionalchinese/maketables.go
@@ -0,0 +1,140 @@
+// 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
+
+// This program generates tables.go:
+// go run maketables.go | gofmt > tables.go
+
+import (
+ "bufio"
+ "fmt"
+ "log"
+ "net/http"
+ "sort"
+ "strings"
+)
+
+func main() {
+ fmt.Printf("// generated by go run maketables.go; DO NOT EDIT\n\n")
+ fmt.Printf("// Package traditionalchinese provides Traditional Chinese encodings such as Big5.\n")
+ fmt.Printf(`package traditionalchinese // import "golang.org/x/text/encoding/traditionalchinese"` + "\n\n")
+
+ res, err := http.Get("http://encoding.spec.whatwg.org/index-big5.txt")
+ if err != nil {
+ log.Fatalf("Get: %v", err)
+ }
+ defer res.Body.Close()
+
+ mapping := [65536]uint32{}
+ reverse := [65536 * 4]uint16{}
+
+ scanner := bufio.NewScanner(res.Body)
+ for scanner.Scan() {
+ s := strings.TrimSpace(scanner.Text())
+ if s == "" || s[0] == '#' {
+ continue
+ }
+ x, y := uint16(0), uint32(0)
+ if _, err := fmt.Sscanf(s, "%d 0x%x", &x, &y); err != nil {
+ log.Fatalf("could not parse %q", s)
+ }
+ if x < 0 || 126*157 <= x {
+ log.Fatalf("Big5 code %d is out of range", x)
+ }
+ mapping[x] = y
+
+ // The WHATWG spec http://encoding.spec.whatwg.org/#indexes says that
+ // "The index pointer for code point in index is the first pointer
+ // corresponding to code point in index", which would normally mean
+ // that the code below should be guarded by "if reverse[y] == 0", but
+ // last instead of first seems to match the behavior of
+ // "iconv -f UTF-8 -t BIG5". For example, U+8005 者 occurs twice in
+ // http://encoding.spec.whatwg.org/index-big5.txt, as index 2148
+ // (encoded as "\x8e\xcd") and index 6543 (encoded as "\xaa\xcc")
+ // and "echo 者 | iconv -f UTF-8 -t BIG5 | xxd" gives "\xaa\xcc".
+ c0, c1 := x/157, x%157
+ if c1 < 0x3f {
+ c1 += 0x40
+ } else {
+ c1 += 0x62
+ }
+ reverse[y] = (0x81+c0)<<8 | c1
+ }
+ if err := scanner.Err(); err != nil {
+ log.Fatalf("scanner error: %v", err)
+ }
+
+ fmt.Printf("// decode is the decoding table from Big5 code to Unicode.\n")
+ fmt.Printf("// It is defined at http://encoding.spec.whatwg.org/index-big5.txt\n")
+ fmt.Printf("var decode = [...]uint32{\n")
+ for i, v := range mapping {
+ if v != 0 {
+ fmt.Printf("\t%d: 0x%08X,\n", i, v)
+ }
+ }
+ fmt.Printf("}\n\n")
+
+ // Any run of at least separation continuous zero entries in the reverse map will
+ // be a separate encode table.
+ const separation = 1024
+
+ intervals := []interval(nil)
+ low, high := -1, -1
+ for i, v := range reverse {
+ if v == 0 {
+ continue
+ }
+ if low < 0 {
+ low = i
+ } else if i-high >= separation {
+ if high >= 0 {
+ intervals = append(intervals, interval{low, high})
+ }
+ low = i
+ }
+ high = i + 1
+ }
+ if high >= 0 {
+ intervals = append(intervals, interval{low, high})
+ }
+ sort.Sort(byDecreasingLength(intervals))
+
+ fmt.Printf("const numEncodeTables = %d\n\n", len(intervals))
+ fmt.Printf("// encodeX are the encoding tables from Unicode to Big5 code,\n")
+ fmt.Printf("// sorted by decreasing length.\n")
+ for i, v := range intervals {
+ fmt.Printf("// encode%d: %5d entries for runes in [%6d, %6d).\n", i, v.len(), v.low, v.high)
+ }
+ fmt.Printf("\n")
+
+ for i, v := range intervals {
+ fmt.Printf("const encode%dLow, encode%dHigh = %d, %d\n\n", i, i, v.low, v.high)
+ fmt.Printf("var encode%d = [...]uint16{\n", i)
+ for j := v.low; j < v.high; j++ {
+ x := reverse[j]
+ if x == 0 {
+ continue
+ }
+ fmt.Printf("\t%d-%d: 0x%04X,\n", j, v.low, x)
+ }
+ fmt.Printf("}\n\n")
+ }
+}
+
+// interval is a half-open interval [low, high).
+type interval struct {
+ low, high int
+}
+
+func (i interval) len() int { return i.high - i.low }
+
+// byDecreasingLength sorts intervals by decreasing length.
+type byDecreasingLength []interval
+
+func (b byDecreasingLength) Len() int { return len(b) }
+func (b byDecreasingLength) Less(i, j int) bool { return b[i].len() > b[j].len() }
+func (b byDecreasingLength) Swap(i, j int) { b[i], b[j] = b[j], b[i] }