in crumb-compiler/src/main/kotlin/com/uber/crumb/internal/wire/ProtoWriter.kt [104:111]
fun writeVarint64(value: Long) {
var value = value
while (value and 0x7fL.inv() != 0L) {
sink.writeByte((value.toInt() and 0x7f) or 0x80)
value = value ushr 7
}
sink.writeByte(value.toInt())
}