81 lines
1.3 KiB
Go
81 lines
1.3 KiB
Go
package router
|
|
|
|
import (
|
|
"fmt"
|
|
)
|
|
|
|
type Router struct {
|
|
selectors []string
|
|
symbols map[string]string
|
|
}
|
|
|
|
func NewRouter() Router {
|
|
return Router{
|
|
symbols: make(map[string]string),
|
|
}
|
|
}
|
|
|
|
func(r *Router) Add(selector string, symbol string) error {
|
|
if r.symbols[selector] != "" {
|
|
return fmt.Errorf("selector %v already set to symbol %v", selector, symbol)
|
|
}
|
|
l := len(selector)
|
|
if (l > 255) {
|
|
return fmt.Errorf("selector too long (is %v, max 255)", l)
|
|
}
|
|
l = len(symbol)
|
|
if (l > 255) {
|
|
return fmt.Errorf("symbol too long (is %v, max 255)", l)
|
|
}
|
|
r.selectors = append(r.selectors, selector)
|
|
r.symbols[selector] = symbol
|
|
return nil
|
|
}
|
|
|
|
func(r *Router) Next() []byte {
|
|
if len(r.selectors) == 0 {
|
|
return []byte{}
|
|
}
|
|
k := r.selectors[0]
|
|
r.selectors = r.selectors[1:]
|
|
v := r.symbols[k]
|
|
if len(r.selectors) == 0 {
|
|
r.symbols = nil
|
|
} else {
|
|
delete(r.symbols, k)
|
|
}
|
|
lk := len(k)
|
|
lv := len(v)
|
|
b := []byte{uint8(lk)}
|
|
b = append(b, k...)
|
|
b = append(b, uint8(lv))
|
|
b = append(b, v...)
|
|
return b
|
|
}
|
|
|
|
func(r *Router) ToBytes() []byte {
|
|
b := []byte{}
|
|
for true {
|
|
v := r.Next()
|
|
if len(v) == 0 {
|
|
break
|
|
}
|
|
b = append(b, v...)
|
|
}
|
|
return b
|
|
}
|
|
|
|
func FromBytes(b []byte) Router {
|
|
rb := NewRouter()
|
|
for len(b) > 0 {
|
|
l := b[0]
|
|
k := b[1:1+l]
|
|
b = b[1+l:]
|
|
l = b[0]
|
|
v := b[1:1+l]
|
|
b = b[1+l:]
|
|
rb.Add(string(k), string(v))
|
|
}
|
|
return rb
|
|
}
|