diff options
Diffstat (limited to 'src/lib/bufio.go')
| -rw-r--r-- | src/lib/bufio.go | 34 |
1 files changed, 31 insertions, 3 deletions
diff --git a/src/lib/bufio.go b/src/lib/bufio.go index f41c4cd3d..11813d6c6 100644 --- a/src/lib/bufio.go +++ b/src/lib/bufio.go @@ -3,8 +3,12 @@ // license that can be found in the LICENSE file. package bufio -import "os" -import "io" + +import ( + "os"; + "io"; + "utf8"; +) // TODO: @@ -65,7 +69,7 @@ func (b *BufRead) Fill() *os.Error { } // Slide existing data to beginning. - if b.w > b.r { + if b.w > b.r { CopySlice(b.buf[0:b.w-b.r], b.buf[b.r:b.w]); b.w -= b.r; } else { @@ -140,6 +144,30 @@ func (b *BufRead) UnreadByte() *os.Error { return nil } +// Read a single Unicode character; returns the rune and its size. +func (b *BufRead) ReadRune() (rune int, size int, err *os.Error) { + for b.r + utf8.UTFMax > b.w && !utf8.FullRune(b.buf[b.r:b.w]) { + n := b.w - b.r; + b.Fill(); + if b.err != nil { + return 0, 0, b.err + } + if b.w - b.r == n { + // no bytes read + if b.r == b.w { + return 0, 0, EndOfFile + } + break; + } + } + rune, size = int(b.buf[b.r]), 1; + if rune >= 0x80 { + rune, size = utf8.DecodeRune(b.buf[b.r:b.w]); + } + b.r += size; + return rune, size, nil +} + // Helper function: look for byte c in array p, // returning its index or -1. func FindByte(p *[]byte, c byte) int { |