fix: use concurrent map for command caching

relates to #333

src/environment.go

@@ -10,12 +10,12 @@ import (
 	"path/filepath"
 	"runtime"
 	"strings"
-	"sync"
 	"time"
 
 	"github.com/distatus/battery"
 	"github.com/shirou/gopsutil/host"
 	"github.com/shirou/gopsutil/process"
+	"github.com/xaionaro-go/atomicmap"
 )
 
 const (
@@ -71,8 +71,7 @@ type environment struct {
 }
 
 var (
-	commands map[string]string = make(map[string]string)
-	lock                       = sync.Mutex{}
+	commands atomicmap.Map = atomicmap.New()
 )
 
 func (env *environment) getenv(key string) string {
@@ -165,8 +164,8 @@ func (env *environment) getPlatform() string {
 }
 
 func (env *environment) runCommand(command string, args ...string) (string, error) {
-	if cmd, ok := commands[command]; ok {
-		command = cmd
+	if cmd, err := commands.Get(command); err == nil {
+		command = cmd.(string)
 	}
 	out, err := exec.Command(command, args...).Output()
 	if err != nil {
@@ -186,14 +185,14 @@ func (env *environment) runShellCommand(shell, command string) string {
 }
 
 func (env *environment) hasCommand(command string) bool {
-	if _, ok := commands[command]; ok {
+	if _, err := commands.Get(command); err == nil {
 		return true
 	}
 	path, err := exec.LookPath(command)
 	if err == nil {
-		lock.Lock()
-		commands[command] = path
-		lock.Unlock()
+		// the error implies we failed to cache the path
+		// ignoring it only affects the path caching, not the functionality
+		_ = commands.Set(command, path)
 		return true
 	}
 	return false

src/go.mod

@@ -15,6 +15,7 @@ require (
 	github.com/shirou/gopsutil v2.20.9+incompatible
 	github.com/stretchr/objx v0.3.0 // indirect
 	github.com/stretchr/testify v1.6.1
+	github.com/xaionaro-go/atomicmap v0.0.0-20200307233044-c040bc137895
 	golang.org/x/sys v0.0.0-20201015000850-e3ed0017c211
 	golang.org/x/text v0.3.3
 	gopkg.in/yaml.v3 v3.0.0-20200615113413-eeeca48fe776 // indirect

src/go.sum

@@ -2,6 +2,8 @@ github.com/JanDeDobbeleer/battery v0.10.0-1 h1:3N3i3xgvrrb3eCuX4kJnmbKzOiqkH1Ly1
 github.com/JanDeDobbeleer/battery v0.10.0-1/go.mod h1:STnSvFLX//eEpkaN7qWRxCWxrWOcssTDgnG4yqq9BRE=
 github.com/JanDeDobbeleer/color v1.3.5-1 h1:joTGC9ShPgXUVWJW4sBv4q9M2rdpTopCysc8fRRAgkY=
 github.com/JanDeDobbeleer/color v1.3.5-1/go.mod h1:GqqLKF1le3EfrbHbYsYa5WdLqfc/PHMdMRbt6tMnqIc=
+github.com/OneOfOne/xxhash v1.2.7 h1:fzrmmkskv067ZQbd9wERNGuxckWw67dyzoMG62p7LMo=
+github.com/OneOfOne/xxhash v1.2.7/go.mod h1:eZbhyaAYD41SGSSsnmcpxVoRiQ/MPUTjUdIIOT9Um7Q=
 github.com/StackExchange/wmi v0.0.0-20190523213315-cbe66965904d h1:G0m3OIz70MZUWq3EgK3CesDbo8upS2Vm9/P3FtgI+Jk=
 github.com/StackExchange/wmi v0.0.0-20190523213315-cbe66965904d/go.mod h1:3eOhrUMpNV+6aFIbp5/iudMxNCF27Vw2OZgy4xEx0Fg=
 github.com/alecthomas/assert v0.0.0-20170929043011-405dbfeb8e38 h1:smF2tmSOzy2Mm+0dGI2AIUHY+w0BUc+4tn40djz7+6U=
@@ -10,9 +12,11 @@ github.com/alecthomas/colour v0.1.0 h1:nOE9rJm6dsZ66RGWYSFrXw461ZIt9A6+nHgL7FRrD
 github.com/alecthomas/colour v0.1.0/go.mod h1:QO9JBoKquHd+jz9nshCh40fOfO+JzsoXy8qTHF68zU0=
 github.com/alecthomas/repr v0.0.0-20201103221029-55c485bd663f h1:jXPaiovuWmnCXfJ8UYiiLtI/LAJPnaZnoV+LfIDEJRc=
 github.com/alecthomas/repr v0.0.0-20201103221029-55c485bd663f/go.mod h1:2kn6fqh/zIyPLmm3ugklbEi5hg5wS435eygvNfaDQL8=
+github.com/cornelk/hashmap v1.0.1/go.mod h1:8wbysTUDnwJGrPZ1Iwsou3m+An6sldFrJItjRhfegCw=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/dchest/siphash v1.1.0/go.mod h1:q+IRvb2gOSrUnYoPqHiyHXS0FOBBOdl6tONBlVnOnt4=
 github.com/go-ole/go-ole v1.2.4 h1:nNBDSCOigTSiarFpYE9J/KtEA1IOW4CNeqT9TQDqCxI=
 github.com/go-ole/go-ole v1.2.4/go.mod h1:XCwSNxSkXRo4vlyPy93sltvi/qJq0jqQhjqQNIwKuxM=
 github.com/jessevdk/go-flags v1.4.0/go.mod h1:4FA24M0QyGHXBuZZK/XkWh8h0e1EYbRYJSGM75WSRxI=
@@ -36,6 +40,10 @@ github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UV
 github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
 github.com/stretchr/testify v1.6.1 h1:hDPOHmpOpP40lSULcqw7IrRb/u7w6RpDC9399XyoNd0=
 github.com/stretchr/testify v1.6.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
+github.com/xaionaro-go/atomicmap v0.0.0-20200307233044-c040bc137895 h1:PFzS0ykP4VVJmqv94Khyp6U5QavIdcrQZw9E13G+Go8=
+github.com/xaionaro-go/atomicmap v0.0.0-20200307233044-c040bc137895/go.mod h1:WgfDl7x9++CVnKSu63ThFhBF3nvgj60Ft1nCgrOSgWM=
+github.com/xaionaro-go/spinlock v0.0.0-20190309154744-55278e21e817 h1:0ikx4JlTx9uNiHGGC4o0k93GhcWOtONYdhk2H8RUnZU=
+github.com/xaionaro-go/spinlock v0.0.0-20190309154744-55278e21e817/go.mod h1:Nb/15eS0BMty6TMuWgRQM8WCDIUlyPZagcpchHT6c9Y=
 golang.org/x/sys v0.0.0-20190912141932-bc967efca4b8/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200116001909-b77594299b42/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20201015000850-e3ed0017c211 h1:9UQO31fZ+0aKQOFldThf7BKPMJTiBfWycGh/u3UoO88=