Source file src/pkg/strconv/makeisprint.go
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13 package main
14
15 import (
16 "bytes"
17 "flag"
18 "fmt"
19 "go/format"
20 "io/ioutil"
21 "log"
22 "unicode"
23 )
24
25 var filename = flag.String("output", "isprint.go", "output file name")
26
27 var (
28 range16 []uint16
29 except16 []uint16
30 range32 []uint32
31 except32 []uint32
32 )
33
34
35
36 func bsearch16(a []uint16, x uint16) int {
37 i, j := 0, len(a)
38 for i < j {
39 h := i + (j-i)/2
40 if a[h] < x {
41 i = h + 1
42 } else {
43 j = h
44 }
45 }
46 return i
47 }
48
49
50
51 func bsearch32(a []uint32, x uint32) int {
52 i, j := 0, len(a)
53 for i < j {
54 h := i + (j-i)/2
55 if a[h] < x {
56 i = h + 1
57 } else {
58 j = h
59 }
60 }
61 return i
62 }
63
64 func isPrint(r rune) bool {
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67
68
69
70
71 if 0 <= r && r < 1<<16 {
72 rr, rang, except := uint16(r), range16, except16
73 i := bsearch16(rang, rr)
74 if i >= len(rang) || rr < rang[i&^1] || rang[i|1] < rr {
75 return false
76 }
77 j := bsearch16(except, rr)
78 return j >= len(except) || except[j] != rr
79 }
80
81 rr, rang, except := uint32(r), range32, except32
82 i := bsearch32(rang, rr)
83 if i >= len(rang) || rr < rang[i&^1] || rang[i|1] < rr {
84 return false
85 }
86 j := bsearch32(except, rr)
87 return j >= len(except) || except[j] != rr
88 }
89
90 func scan(min, max rune) (rang, except []uint32) {
91 lo := rune(-1)
92 for i := min; ; i++ {
93 if (i > max || !unicode.IsPrint(i)) && lo >= 0 {
94
95 if i+1 <= max && unicode.IsPrint(i+1) {
96 except = append(except, uint32(i))
97 continue
98 }
99 rang = append(rang, uint32(lo), uint32(i-1))
100 lo = -1
101 }
102 if i > max {
103 break
104 }
105 if lo < 0 && unicode.IsPrint(i) {
106 lo = i
107 }
108 }
109 return
110 }
111
112 func to16(x []uint32) []uint16 {
113 var y []uint16
114 for _, v := range x {
115 if uint32(uint16(v)) != v {
116 panic("bad 32->16 conversion")
117 }
118 y = append(y, uint16(v))
119 }
120 return y
121 }
122
123 func main() {
124 flag.Parse()
125
126 rang, except := scan(0, 0xFFFF)
127 range16 = to16(rang)
128 except16 = to16(except)
129 range32, except32 = scan(0x10000, unicode.MaxRune)
130
131 for i := rune(0); i <= unicode.MaxRune; i++ {
132 if isPrint(i) != unicode.IsPrint(i) {
133 log.Fatalf("%U: isPrint=%v, want %v\n", i, isPrint(i), unicode.IsPrint(i))
134 }
135 }
136
137 var buf bytes.Buffer
138
139 fmt.Fprintf(&buf, `// Copyright 2013 The Go Authors. All rights reserved.
140 // Use of this source code is governed by a BSD-style
141 // license that can be found in the LICENSE file.`+"\n\n")
142 fmt.Fprintf(&buf, "// Code generated by go run makeisprint.go -output isprint.go; DO NOT EDIT.\n\n")
143 fmt.Fprintf(&buf, "package strconv\n\n")
144
145 fmt.Fprintf(&buf, "// (%d+%d+%d)*2 + (%d)*4 = %d bytes\n\n",
146 len(range16), len(except16), len(except32),
147 len(range32),
148 (len(range16)+len(except16)+len(except32))*2+
149 (len(range32))*4)
150
151 fmt.Fprintf(&buf, "var isPrint16 = []uint16{\n")
152 for i := 0; i < len(range16); i += 2 {
153 fmt.Fprintf(&buf, "\t%#04x, %#04x,\n", range16[i], range16[i+1])
154 }
155 fmt.Fprintf(&buf, "}\n\n")
156
157 fmt.Fprintf(&buf, "var isNotPrint16 = []uint16{\n")
158 for _, r := range except16 {
159 fmt.Fprintf(&buf, "\t%#04x,\n", r)
160 }
161 fmt.Fprintf(&buf, "}\n\n")
162
163 fmt.Fprintf(&buf, "var isPrint32 = []uint32{\n")
164 for i := 0; i < len(range32); i += 2 {
165 fmt.Fprintf(&buf, "\t%#06x, %#06x,\n", range32[i], range32[i+1])
166 }
167 fmt.Fprintf(&buf, "}\n\n")
168
169 fmt.Fprintf(&buf, "var isNotPrint32 = []uint16{ // add 0x10000 to each entry\n")
170 for _, r := range except32 {
171 if r >= 0x20000 {
172 log.Fatalf("%U too big for isNotPrint32\n", r)
173 }
174 fmt.Fprintf(&buf, "\t%#04x,\n", r-0x10000)
175 }
176 fmt.Fprintf(&buf, "}\n\n")
177
178
179 fmt.Fprintf(&buf, "// isGraphic lists the graphic runes not matched by IsPrint.\n")
180 fmt.Fprintf(&buf, "var isGraphic = []uint16{\n")
181 for r := rune(0); r <= unicode.MaxRune; r++ {
182 if unicode.IsPrint(r) != unicode.IsGraphic(r) {
183
184 if !unicode.IsGraphic(r) {
185 log.Fatalf("%U is printable but not graphic\n", r)
186 }
187 if r > 0xFFFF {
188 log.Fatalf("%U too big for isGraphic\n", r)
189 }
190 fmt.Fprintf(&buf, "\t%#04x,\n", r)
191 }
192 }
193 fmt.Fprintf(&buf, "}\n")
194
195 data, err := format.Source(buf.Bytes())
196 if err != nil {
197 log.Fatal(err)
198 }
199 err = ioutil.WriteFile(*filename, data, 0644)
200 if err != nil {
201 log.Fatal(err)
202 }
203 }
204
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