init

utils.go

@@ -0,0 +1,107 @@
+package main
+
+import (
+	"errors"
+	"fmt"
+	"os"
+	"runtime"
+	"time"
+
+	"gosuv/logxxx"
+)
+
+var ErrGoTimeout = errors.New("GoTimeoutFunc")
+
+func GoFunc(f func() error) chan error {
+	ch := make(chan error)
+	go func() {
+		ch <- f()
+	}()
+	return ch
+}
+
+func GoTimeoutFunc(timeout time.Duration, f func() error) chan error {
+	ch := make(chan error)
+	go func() {
+		var err error
+		select {
+		case err = <-GoFunc(f):
+			ch <- err
+		case <-time.After(timeout):
+			logxxx.Debugf("timeout: %v", f)
+			ch <- ErrGoTimeout
+		}
+	}()
+	return ch
+}
+
+func GoTimeout(f func() error, timeout time.Duration) (err error) {
+	done := make(chan bool)
+	go func() {
+		err = f()
+		done <- true
+	}()
+	select {
+	case <-time.After(timeout):
+		return ErrGoTimeout
+	case <-done:
+		return
+	}
+}
+
+func IsDir(dir string) bool {
+	fi, err := os.Stat(dir)
+	return err == nil && fi.IsDir()
+}
+
+func UserHomeDir() string {
+	if runtime.GOOS == "windows" {
+		home := os.Getenv("HOMEDRIVE") + os.Getenv("HOMEPATH")
+		if home == "" {
+			home = os.Getenv("USERPROFILE")
+		}
+		return home
+	}
+	return os.Getenv("HOME")
+}
+
+// askForConfirmation uses Scanln to parse user input. A user must type in "yes" or "no" and
+// then press enter. It has fuzzy matching, so "y", "Y", "yes", "YES", and "Yes" all count as
+// confirmations. If the input is not recognized, it will ask again. The function does not return
+// until it gets a valid response from the user. Typically, you should use fmt to print out a question
+// before calling askForConfirmation. E.g. fmt.Println("WARNING: Are you sure? (yes/no)")
+func askForConfirmation() bool {
+	var response string
+	_, err := fmt.Scanln(&response)
+	if err != nil {
+		logxxx.Fatal(err)
+	}
+	okayResponses := []string{"y", "Y", "yes", "Yes", "YES"}
+	nokayResponses := []string{"n", "N", "no", "No", "NO"}
+	if containsString(okayResponses, response) {
+		return true
+	} else if containsString(nokayResponses, response) {
+		return false
+	} else {
+		fmt.Println("Please type yes or no and then press enter:")
+		return askForConfirmation()
+	}
+}
+
+// You might want to put the following two functions in a separate utility package.
+
+// posString returns the first index of element in slice.
+// If slice does not contain element, returns -1.
+func posString(slice []string, element string) int {
+	for index, elem := range slice {
+		if elem == element {
+			return index
+		}
+	}
+	return -1
+}
+
+// containsString returns true iff slice contains element
+func containsString(slice []string, element string) bool {
+	return !(posString(slice, element) == -1)
+}