1 files changed, 140 insertions, 0 deletions
diff --git a/install/utils.go b/install/utils.go
new file mode 100644
index 0000000..d34ac8c
--- /dev/null
+++ b/install/utils.go
@@ -0,0 +1,140 @@
+package install
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+)
+
+func lineInFile(name string, lookFor string) bool {
+	f, err := os.Open(name)
+	if err != nil {
+		return false
+	}
+	defer f.Close()
+	r := bufio.NewReader(f)
+	prefix := []byte{}
+	for {
+		line, isPrefix, err := r.ReadLine()
+		if err == io.EOF {
+			return false
+		}
+		if err != nil {
+			return false
+		}
+		if isPrefix {
+			prefix = append(prefix, line...)
+			continue
+		}
+		line = append(prefix, line...)
+		if string(line) == lookFor {
+			return true
+		}
+		prefix = prefix[:0]
+	}
+}
+
+func createFile(name string, content string) error {
+	// make sure file directory exists
+	if err := os.MkdirAll(filepath.Dir(name), 0775); err != nil {
+		return err
+	}
+
+	// create the file
+	f, err := os.Create(name)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+
+	// write file content
+	_, err = f.WriteString(fmt.Sprintf("%s\n", content))
+	return err
+}
+
+func appendToFile(name string, content string) error {
+	f, err := os.OpenFile(name, os.O_RDWR|os.O_APPEND, 0)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+	_, err = f.WriteString(fmt.Sprintf("\n%s\n", content))
+	return err
+}
+
+func removeFromFile(name string, content string) error {
+	backup := name + ".bck"
+	err := copyFile(name, backup)
+	if err != nil {
+		return err
+	}
+	temp, err := removeContentToTempFile(name, content)
+	if err != nil {
+		return err
+	}
+
+	err = copyFile(temp, name)
+	if err != nil {
+		return err
+	}
+
+	return os.Remove(backup)
+}
+
+func removeContentToTempFile(name, content string) (string, error) {
+	rf, err := os.Open(name)
+	if err != nil {
+		return "", err
+	}
+	defer rf.Close()
+	wf, err := ioutil.TempFile("/tmp", "complete-")
+	if err != nil {
+		return "", err
+	}
+	defer wf.Close()
+
+	r := bufio.NewReader(rf)
+	prefix := []byte{}
+	for {
+		line, isPrefix, err := r.ReadLine()
+		if err == io.EOF {
+			break
+		}
+		if err != nil {
+			return "", err
+		}
+		if isPrefix {
+			prefix = append(prefix, line...)
+			continue
+		}
+		line = append(prefix, line...)
+		str := string(line)
+		if str == content {
+			continue
+		}
+		_, err = wf.WriteString(str + "\n")
+		if err != nil {
+			return "", err
+		}
+		prefix = prefix[:0]
+	}
+	return wf.Name(), nil
+}
+
+func copyFile(src string, dst string) error {
+	in, err := os.Open(src)
+	if err != nil {
+		return err
+	}
+	defer in.Close()
+	out, err := os.Create(dst)
+	if err != nil {
+		return err
+	}
+	defer out.Close()
+	_, err = io.Copy(out, in)
+	return err
+}