Precompile port-filter regexp

Author: cmaglie

serial_darwin.go

@@ -6,10 +6,15 @@
 
 package serial
 
-import "golang.org/x/sys/unix"
+import (
+	"regexp"
+
+	"golang.org/x/sys/unix"
+)
 
 const devFolder = "/dev"
-const regexFilter = "^(cu|tty)\\..*"
+
+var osPortFiler = regexp.MustCompile("^(cu|tty)\\..*")
 
 const ioctlTcgetattr = unix.TIOCGETA
 const ioctlTcsetattr = unix.TIOCSETA

serial_freebsd.go

@@ -6,10 +6,15 @@
 
 package serial
 
-import "golang.org/x/sys/unix"
+import (
+	"regexp"
+
+	"golang.org/x/sys/unix"
+)
 
 const devFolder = "/dev"
-const regexFilter = "^(cu|tty)\\..*"
+
+var osPortFiler = regexp.MustCompile("^(cu|tty)\\..*")
 
 // termios manipulation functions
 

serial_linux.go

@@ -6,10 +6,15 @@
 
 package serial
 
-import "golang.org/x/sys/unix"
+import (
+	"regexp"
+
+	"golang.org/x/sys/unix"
+)
 
 const devFolder = "/dev"
-const regexFilter = "(ttyS|ttyHS|ttyUSB|ttyACM|ttyAMA|rfcomm|ttyO|ttymxc)[0-9]{1,3}"
+
+var osPortFilter = regexp.MustCompile("(ttyS|ttyHS|ttyUSB|ttyACM|ttyAMA|rfcomm|ttyO|ttymxc)[0-9]{1,3}")
 
 // termios manipulation functions
 

serial_openbsd.go

@@ -6,10 +6,15 @@
 
 package serial
 
-import "golang.org/x/sys/unix"
+import (
+	"regexp"
+
+	"golang.org/x/sys/unix"
+)
 
 const devFolder = "/dev"
-const regexFilter = "^(cu|tty)\\..*"
+
+var osPortFiler = regexp.MustCompile("^(cu|tty)\\..*")
 
 // termios manipulation functions
 

serial_unix.go

@@ -11,7 +11,6 @@ package serial
 import (
 	"fmt"
 	"os"
-	"regexp"
 	"strings"
 	"sync"
 	"sync/atomic"
@@ -298,18 +297,14 @@ func nativeGetPortsList() ([]string, error) {
 	}
 
 	ports := make([]string, 0, len(files))
-	regex, err := regexp.Compile(regexFilter)
-	if err != nil {
-		return nil, err
-	}
 	for _, f := range files {
 		// Skip folders
 		if f.IsDir() {
 			continue
 		}
 
 		// Keep only devices with the correct name
-		if !regex.MatchString(f.Name()) {
+		if !osPortFilter.MatchString(f.Name()) {
 			continue
 		}