diff options
Diffstat (limited to 'vendor/github.com/mattermost/rsc/regexp/regmerge/utf.go')
| -rw-r--r-- | vendor/github.com/mattermost/rsc/regexp/regmerge/utf.go | 270 |
1 files changed, 0 insertions, 270 deletions
diff --git a/vendor/github.com/mattermost/rsc/regexp/regmerge/utf.go b/vendor/github.com/mattermost/rsc/regexp/regmerge/utf.go deleted file mode 100644 index 605e01c10..000000000 --- a/vendor/github.com/mattermost/rsc/regexp/regmerge/utf.go +++ /dev/null @@ -1,270 +0,0 @@ -// Copyright 2011 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. - -// Copy of code.google.com/p/codesearch/regexp/utf.go. - -package main - -import ( - "regexp/syntax" - "unicode" - "unicode/utf8" -) - -const ( - instFail = syntax.InstFail - instAlt = syntax.InstAlt - instByteRange = syntax.InstRune | 0x80 // local opcode - - argFold = 1 << 16 -) - -func toByteProg(prog *syntax.Prog) error { - var b runeBuilder - for pc := range prog.Inst { - i := &prog.Inst[pc] - switch i.Op { - case syntax.InstRune, syntax.InstRune1: - // General rune range. PIA. - // TODO: Pick off single-byte case. - if lo, hi, fold, ok := oneByteRange(i); ok { - i.Op = instByteRange - i.Arg = uint32(lo)<<8 | uint32(hi) - if fold { - i.Arg |= argFold - } - break - } - - r := i.Rune - if syntax.Flags(i.Arg)&syntax.FoldCase != 0 { - // Build folded list. - var rr []rune - if len(r) == 1 { - rr = appendFoldedRange(rr, r[0], r[0]) - } else { - for j := 0; j < len(r); j += 2 { - rr = appendFoldedRange(rr, r[j], r[j+1]) - } - } - r = rr - } - - b.init(prog, uint32(pc), i.Out) - if len(r) == 1 { - b.addRange(r[0], r[0], false) - } else { - for j := 0; j < len(r); j += 2 { - b.addRange(r[j], r[j+1], false) - } - } - - case syntax.InstRuneAny, syntax.InstRuneAnyNotNL: - // All runes. - // AnyNotNL should exclude \n but the line-at-a-time - // execution takes care of that for us. - b.init(prog, uint32(pc), i.Out) - b.addRange(0, unicode.MaxRune, false) - } - } - return nil -} - -func oneByteRange(i *syntax.Inst) (lo, hi byte, fold, ok bool) { - if i.Op == syntax.InstRune1 { - r := i.Rune[0] - if r < utf8.RuneSelf { - return byte(r), byte(r), false, true - } - } - if i.Op != syntax.InstRune { - return - } - fold = syntax.Flags(i.Arg)&syntax.FoldCase != 0 - if len(i.Rune) == 1 || len(i.Rune) == 2 && i.Rune[0] == i.Rune[1] { - r := i.Rune[0] - if r >= utf8.RuneSelf { - return - } - if fold && !asciiFold(r) { - return - } - return byte(r), byte(r), fold, true - } - if len(i.Rune) == 2 && i.Rune[1] < utf8.RuneSelf { - if fold { - for r := i.Rune[0]; r <= i.Rune[1]; r++ { - if asciiFold(r) { - return - } - } - } - return byte(i.Rune[0]), byte(i.Rune[1]), fold, true - } - if len(i.Rune) == 4 && i.Rune[0] == i.Rune[1] && i.Rune[2] == i.Rune[3] && unicode.SimpleFold(i.Rune[0]) == i.Rune[2] && unicode.SimpleFold(i.Rune[2]) == i.Rune[0] { - return byte(i.Rune[0]), byte(i.Rune[0]), true, true - } - - return -} - -func asciiFold(r rune) bool { - if r >= utf8.RuneSelf { - return false - } - r1 := unicode.SimpleFold(r) - if r1 >= utf8.RuneSelf { - return false - } - if r1 == r { - return true - } - return unicode.SimpleFold(r1) == r -} - -func maxRune(n int) rune { - b := 0 - if n == 1 { - b = 7 - } else { - b = 8 - (n + 1) + 6*(n-1) - } - return 1<<uint(b) - 1 -} - -type cacheKey struct { - lo, hi uint8 - fold bool - next uint32 -} - -type runeBuilder struct { - begin uint32 - out uint32 - cache map[cacheKey]uint32 - p *syntax.Prog -} - -func (b *runeBuilder) init(p *syntax.Prog, begin, out uint32) { - // We will rewrite p.Inst[begin] to hold the accumulated - // machine. For now, there is no match. - p.Inst[begin].Op = instFail - - b.begin = begin - b.out = out - if b.cache == nil { - b.cache = make(map[cacheKey]uint32) - } - for k := range b.cache { - delete(b.cache, k) - } - b.p = p -} - -func (b *runeBuilder) uncachedSuffix(lo, hi byte, fold bool, next uint32) uint32 { - if next == 0 { - next = b.out - } - pc := len(b.p.Inst) - i := syntax.Inst{Op: instByteRange, Arg: uint32(lo)<<8 | uint32(hi), Out: next} - if fold { - i.Arg |= argFold - } - b.p.Inst = append(b.p.Inst, i) - return uint32(pc) -} - -func (b *runeBuilder) suffix(lo, hi byte, fold bool, next uint32) uint32 { - if lo < 0x80 || hi > 0xbf { - // Not a continuation byte, no need to cache. - return b.uncachedSuffix(lo, hi, fold, next) - } - - key := cacheKey{lo, hi, fold, next} - if pc, ok := b.cache[key]; ok { - return pc - } - - pc := b.uncachedSuffix(lo, hi, fold, next) - b.cache[key] = pc - return pc -} - -func (b *runeBuilder) addBranch(pc uint32) { - // Add pc to the branch at the beginning. - i := &b.p.Inst[b.begin] - switch i.Op { - case syntax.InstFail: - i.Op = syntax.InstNop - i.Out = pc - return - case syntax.InstNop: - i.Op = syntax.InstAlt - i.Arg = pc - return - case syntax.InstAlt: - apc := uint32(len(b.p.Inst)) - b.p.Inst = append(b.p.Inst, syntax.Inst{Op: instAlt, Out: i.Arg, Arg: pc}) - i = &b.p.Inst[b.begin] - i.Arg = apc - b.begin = apc - } -} - -func (b *runeBuilder) addRange(lo, hi rune, fold bool) { - if lo > hi { - return - } - - // TODO: Pick off 80-10FFFF for special handling? - if lo == 0x80 && hi == 0x10FFFF { - } - - // Split range into same-length sized ranges. - for i := 1; i < utf8.UTFMax; i++ { - max := maxRune(i) - if lo <= max && max < hi { - b.addRange(lo, max, fold) - b.addRange(max+1, hi, fold) - return - } - } - - // ASCII range is special. - if hi < utf8.RuneSelf { - b.addBranch(b.suffix(byte(lo), byte(hi), fold, 0)) - return - } - - // Split range into sections that agree on leading bytes. - for i := 1; i < utf8.UTFMax; i++ { - m := rune(1)<<uint(6*i) - 1 // last i bytes of UTF-8 sequence - if lo&^m != hi&^m { - if lo&m != 0 { - b.addRange(lo, lo|m, fold) - b.addRange((lo|m)+1, hi, fold) - return - } - if hi&m != m { - b.addRange(lo, hi&^m-1, fold) - b.addRange(hi&^m, hi, fold) - return - } - } - } - - // Finally. Generate byte matching equivalent for lo-hi. - var ulo, uhi [utf8.UTFMax]byte - n := utf8.EncodeRune(ulo[:], lo) - m := utf8.EncodeRune(uhi[:], hi) - if n != m { - panic("codesearch/regexp: bad utf-8 math") - } - - pc := uint32(0) - for i := n - 1; i >= 0; i-- { - pc = b.suffix(ulo[i], uhi[i], false, pc) - } - b.addBranch(pc) -} |