add chain and env commands

1 files changed, 105 insertions, 0 deletions

diff --git a/pkg/server/env.go b/pkg/server/env.go
new file mode 100644
index 0000000..769342a
--- /dev/null
+++ b/pkg/server/env.go
@@ -0,0 +1,105 @@
+package server
+
+import (
+	"sync"
+)
+
+func init() {
+	setHandler(envSet, "env", "set")
+	setHandler(envGet, "env", "get")
+	setHandler(envShow, "env", "show")
+	setHandler(envShow, "env", "print")
+	setHandler(envUnset, "env", "unset")
+}
+
+type env struct {
+	m map[string]string
+	sync.Mutex
+}
+
+func (e *env) get(key string) (string, bool) {
+	e.Lock()
+	defer e.Unlock()
+
+	v, ok := e.m[key]
+
+	return v, ok
+}
+
+func (e *env) set(key string, value string) {
+	e.Lock()
+	defer e.Unlock()
+
+	if e.m == nil {
+		e.m = make(map[string]string)
+	}
+
+	e.m[key] = value
+}
+
+func (e *env) unset(key string) bool {
+	e.Lock()
+	defer e.Unlock()
+
+	if e.m == nil {
+		return false
+	}
+
+	if _, ok := e.m[key]; !ok {
+		return false
+	}
+
+	delete(e.m, key)
+
+	return true
+}
+
+func (e *env) each(f func (string, string) bool) {
+	e.Lock()
+	defer e.Unlock()
+
+	for k, v := range e.m {
+		if !f(k, v) {
+			break
+		}
+	}
+}
+
+func envSet(r *request) {
+	r.expect(2)
+
+	r.c.s.env.set(r.args[0], r.args[1])
+}
+
+func envGet(r *request) {
+	r.expect(1)
+
+	if v, ok := r.c.s.env.get(r.args[0]); ok {
+		r.Print(v)
+	} else {
+		r.Print("no such variable")
+	}
+}
+
+func envUnset(r *request) {
+	r.expect(1)
+
+	if !r.c.s.env.unset(r.args[0]) {
+		r.Print("no such variable")
+	}
+}
+
+func envShow(r *request) {
+	r.expect(0, 1)
+
+	switch r.argc {
+	case 0:
+		r.c.s.env.each(func (k string, v string) bool {
+			r.Println(k, v)
+			return true
+		})
+
+	case 1:
+		envGet(r)
+	}
+}