Rename semaphore channel var name

Signed-off-by: Carlos Martín <carlos.martin.sanchez@gmail.com>

Author: carlosms

memory/memory.go

@@ -127,7 +127,7 @@ func (q *Queue) Consume(advertisedWindow int) (queue.JobIter, error) {
 }
 
 if advertisedWindow > 0 {
-jobIter.sem = make(chan struct{}, advertisedWindow)
+jobIter.chn = make(chan struct{}, advertisedWindow)
 }
 
 return &jobIter, nil
@@ -138,15 +138,15 @@ type JobIter struct {
 q *Queue
 closed bool
 finite bool
-sem chan struct{}
+chn chan struct{}
 *sync.RWMutex
 }
 
 // Acknowledger implements a queue.Acknowledger interface.
 type Acknowledger struct {
 q *Queue
 j *queue.Job
-sem chan struct{}
+chn chan struct{}
 }
 
 // Ack is called when the Job has finished.
@@ -171,8 +171,8 @@ func (a *Acknowledger) Reject(requeue bool) error {
 }
 
 func (a *Acknowledger) release() {
-if a.sem != nil {
-<-a.sem
+if a.chn != nil {
+<-a.chn
 }
 }
 
@@ -213,7 +213,7 @@ func (i *JobIter) next() (*queue.Job, error) {
 }
 
 j := i.q.jobs[i.q.idx]
-j.Acknowledger = &Acknowledger{j: j, q: i.q, sem: i.sem}
+j.Acknowledger = &Acknowledger{j: j, q: i.q, chn: i.chn}
 i.q.idx++
 
 return j, nil
@@ -228,13 +228,13 @@ func (i *JobIter) Close() error {
 }
 
 func (i *JobIter) acquire() {
-if i.sem != nil {
-i.sem <- struct{}{}
+if i.chn != nil {
+i.chn <- struct{}{}
 }
 }
 
 func (i *JobIter) release() {
-if i.sem != nil {
-<-i.sem
+if i.chn != nil {
+<-i.chn
 }
 }