brotli/matchfinder/emitter.go

35 lines
845 B
Go

package matchfinder
// An absoluteMatch is like a Match, but it stores indexes into the byte
// stream instead of lengths.
type absoluteMatch struct {
// Start is the index of the first byte.
Start int
// End is the index of the byte after the last byte
// (so that End - Start = Length).
End int
// Match is the index of the previous data that matches
// (Start - Match = Distance).
Match int
}
// A matchEmitter manages the output of matches for a MatchFinder.
type matchEmitter struct {
// Dst is the destination slice that Matches are added to.
Dst []Match
// NextEmit is the index of the next byte to emit.
NextEmit int
}
func (e *matchEmitter) emit(m absoluteMatch) {
e.Dst = append(e.Dst, Match{
Unmatched: m.Start - e.NextEmit,
Length: m.End - m.Start,
Distance: m.Start - m.Match,
})
e.NextEmit = m.End
}