Add Go implementation of checkerlib

go/checkerlib/go.mod

@@ -0,0 +1,6 @@
+module github.com/fausecteam/ctf-gameserver/go/checkerlib
+
+require (
+	golang.org/x/crypto v0.0.0-20200604202706-70a84ac30bf9
+	golang.org/x/sys v0.0.0-20200610111108-226ff32320da // indirect
+)

go/checkerlib/go.sum

@@ -0,0 +1,10 @@
+golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
+golang.org/x/crypto v0.0.0-20200604202706-70a84ac30bf9 h1:vEg9joUBmeBcK9iSJftGNf3coIG4HqZElCPehJsfAYM=
+golang.org/x/crypto v0.0.0-20200604202706-70a84ac30bf9/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
+golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
+golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/sys v0.0.0-20190412213103-97732733099d h1:+R4KGOnez64A81RvjARKc4UT5/tI9ujCIVX+P5KiHuI=
+golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20200610111108-226ff32320da h1:bGb80FudwxpeucJUjPYJXuJ8Hk91vNtfvrymzwiei38=
+golang.org/x/sys v0.0.0-20200610111108-226ff32320da/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=

go/checkerlib/ipc.go

@@ -0,0 +1,69 @@
+// Communication with checkermaster
+
+package checkerlib
+
+import (
+	"bufio"
+	"bytes"
+	"encoding/json"
+	"io"
+	"sync"
+)
+
+type ipcData struct {
+	sync.Mutex
+
+	in  *bufio.Scanner
+	out io.Writer
+}
+
+func (i *ipcData) Send(action string, param interface{}) {
+	ipc.Lock()
+	defer ipc.Unlock()
+
+	i.send(action, param)
+}
+func (i *ipcData) SendRecv(action string, param interface{}) interface{} {
+	ipc.Lock()
+	defer ipc.Unlock()
+
+	i.send(action, param)
+	return i.recv()
+}
+
+func (i *ipcData) send(action string, param interface{}) {
+	data := struct {
+		Action string      `json:"action"`
+		Param  interface{} `json:"param"`
+	}{
+		action,
+		param,
+	}
+
+	x, err := json.Marshal(data)
+	if err != nil {
+		panic(err)
+	}
+	// Make sure that our JSON consists of just a single line as required
+	// by IPC protocol
+	x = append(bytes.Replace(x, []byte{'\n'}, nil, -1), '\n')
+
+	_, err = i.out.Write(x)
+	if err != nil {
+		panic(err)
+	}
+}
+
+func (i *ipcData) recv() interface{} {
+	if !i.in.Scan() {
+		panic(i.in.Err())
+	}
+	var x struct {
+		Response interface{} `json:"response"`
+	}
+	err := json.Unmarshal(i.in.Bytes(), &x)
+	if err != nil {
+		panic(err)
+	}
+	return x.Response
+}