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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-28 13:14:23 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-28 13:14:23 +0000
commit73df946d56c74384511a194dd01dbe099584fd1a (patch)
treefd0bcea490dd81327ddfbb31e215439672c9a068 /src/strconv/makeisprint.go
parentInitial commit. (diff)
downloadgolang-1.16-73df946d56c74384511a194dd01dbe099584fd1a.tar.xz
golang-1.16-73df946d56c74384511a194dd01dbe099584fd1a.zip
Adding upstream version 1.16.10.upstream/1.16.10upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/strconv/makeisprint.go')
-rw-r--r--src/strconv/makeisprint.go203
1 files changed, 203 insertions, 0 deletions
diff --git a/src/strconv/makeisprint.go b/src/strconv/makeisprint.go
new file mode 100644
index 0000000..0e6e90a
--- /dev/null
+++ b/src/strconv/makeisprint.go
@@ -0,0 +1,203 @@
+// Copyright 2012 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
+
+//
+// usage:
+//
+// go run makeisprint.go -output isprint.go
+//
+
+package main
+
+import (
+ "bytes"
+ "flag"
+ "fmt"
+ "go/format"
+ "log"
+ "os"
+ "unicode"
+)
+
+var filename = flag.String("output", "isprint.go", "output file name")
+
+var (
+ range16 []uint16
+ except16 []uint16
+ range32 []uint32
+ except32 []uint32
+)
+
+// bsearch16 returns the smallest i such that a[i] >= x.
+// If there is no such i, bsearch16 returns len(a).
+func bsearch16(a []uint16, x uint16) int {
+ i, j := 0, len(a)
+ for i < j {
+ h := i + (j-i)/2
+ if a[h] < x {
+ i = h + 1
+ } else {
+ j = h
+ }
+ }
+ return i
+}
+
+// bsearch32 returns the smallest i such that a[i] >= x.
+// If there is no such i, bsearch32 returns len(a).
+func bsearch32(a []uint32, x uint32) int {
+ i, j := 0, len(a)
+ for i < j {
+ h := i + (j-i)/2
+ if a[h] < x {
+ i = h + 1
+ } else {
+ j = h
+ }
+ }
+ return i
+}
+
+func isPrint(r rune) bool {
+ // Same algorithm, either on uint16 or uint32 value.
+ // First, find first i such that rang[i] >= x.
+ // This is the index of either the start or end of a pair that might span x.
+ // The start is even (rang[i&^1]) and the end is odd (rang[i|1]).
+ // If we find x in a range, make sure x is not in exception list.
+
+ if 0 <= r && r < 1<<16 {
+ rr, rang, except := uint16(r), range16, except16
+ i := bsearch16(rang, rr)
+ if i >= len(rang) || rr < rang[i&^1] || rang[i|1] < rr {
+ return false
+ }
+ j := bsearch16(except, rr)
+ return j >= len(except) || except[j] != rr
+ }
+
+ rr, rang, except := uint32(r), range32, except32
+ i := bsearch32(rang, rr)
+ if i >= len(rang) || rr < rang[i&^1] || rang[i|1] < rr {
+ return false
+ }
+ j := bsearch32(except, rr)
+ return j >= len(except) || except[j] != rr
+}
+
+func scan(min, max rune) (rang, except []uint32) {
+ lo := rune(-1)
+ for i := min; ; i++ {
+ if (i > max || !unicode.IsPrint(i)) && lo >= 0 {
+ // End range, but avoid flip flop.
+ if i+1 <= max && unicode.IsPrint(i+1) {
+ except = append(except, uint32(i))
+ continue
+ }
+ rang = append(rang, uint32(lo), uint32(i-1))
+ lo = -1
+ }
+ if i > max {
+ break
+ }
+ if lo < 0 && unicode.IsPrint(i) {
+ lo = i
+ }
+ }
+ return
+}
+
+func to16(x []uint32) []uint16 {
+ var y []uint16
+ for _, v := range x {
+ if uint32(uint16(v)) != v {
+ panic("bad 32->16 conversion")
+ }
+ y = append(y, uint16(v))
+ }
+ return y
+}
+
+func main() {
+ flag.Parse()
+
+ rang, except := scan(0, 0xFFFF)
+ range16 = to16(rang)
+ except16 = to16(except)
+ range32, except32 = scan(0x10000, unicode.MaxRune)
+
+ for i := rune(0); i <= unicode.MaxRune; i++ {
+ if isPrint(i) != unicode.IsPrint(i) {
+ log.Fatalf("%U: isPrint=%v, want %v\n", i, isPrint(i), unicode.IsPrint(i))
+ }
+ }
+
+ var buf bytes.Buffer
+
+ fmt.Fprintf(&buf, `// 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.`+"\n\n")
+ fmt.Fprintf(&buf, "// Code generated by go run makeisprint.go -output isprint.go; DO NOT EDIT.\n\n")
+ fmt.Fprintf(&buf, "package strconv\n\n")
+
+ fmt.Fprintf(&buf, "// (%d+%d+%d)*2 + (%d)*4 = %d bytes\n\n",
+ len(range16), len(except16), len(except32),
+ len(range32),
+ (len(range16)+len(except16)+len(except32))*2+
+ (len(range32))*4)
+
+ fmt.Fprintf(&buf, "var isPrint16 = []uint16{\n")
+ for i := 0; i < len(range16); i += 2 {
+ fmt.Fprintf(&buf, "\t%#04x, %#04x,\n", range16[i], range16[i+1])
+ }
+ fmt.Fprintf(&buf, "}\n\n")
+
+ fmt.Fprintf(&buf, "var isNotPrint16 = []uint16{\n")
+ for _, r := range except16 {
+ fmt.Fprintf(&buf, "\t%#04x,\n", r)
+ }
+ fmt.Fprintf(&buf, "}\n\n")
+
+ fmt.Fprintf(&buf, "var isPrint32 = []uint32{\n")
+ for i := 0; i < len(range32); i += 2 {
+ fmt.Fprintf(&buf, "\t%#06x, %#06x,\n", range32[i], range32[i+1])
+ }
+ fmt.Fprintf(&buf, "}\n\n")
+
+ fmt.Fprintf(&buf, "var isNotPrint32 = []uint16{ // add 0x10000 to each entry\n")
+ for _, r := range except32 {
+ if r >= 0x20000 {
+ log.Fatalf("%U too big for isNotPrint32\n", r)
+ }
+ fmt.Fprintf(&buf, "\t%#04x,\n", r-0x10000)
+ }
+ fmt.Fprintf(&buf, "}\n\n")
+
+ // The list of graphic but not "printable" runes is short. Just make one easy table.
+ fmt.Fprintf(&buf, "// isGraphic lists the graphic runes not matched by IsPrint.\n")
+ fmt.Fprintf(&buf, "var isGraphic = []uint16{\n")
+ for r := rune(0); r <= unicode.MaxRune; r++ {
+ if unicode.IsPrint(r) != unicode.IsGraphic(r) {
+ // Sanity check.
+ if !unicode.IsGraphic(r) {
+ log.Fatalf("%U is printable but not graphic\n", r)
+ }
+ if r > 0xFFFF { // We expect only 16-bit values.
+ log.Fatalf("%U too big for isGraphic\n", r)
+ }
+ fmt.Fprintf(&buf, "\t%#04x,\n", r)
+ }
+ }
+ fmt.Fprintf(&buf, "}\n")
+
+ data, err := format.Source(buf.Bytes())
+ if err != nil {
+ log.Fatal(err)
+ }
+ err = os.WriteFile(*filename, data, 0644)
+ if err != nil {
+ log.Fatal(err)
+ }
+}