Support fopen by flags. Fixes #89 (#732)

noarch/stdio.go

@@ -6,6 +6,7 @@ import (
 	"io/ioutil"
 	"os"
 	"reflect"
+	"strings"
 )
 
 // Programs generated by c2go will reference noarch.Stdin instead of os.Stdin
@@ -65,9 +66,26 @@ func Fopen(filePath, mode []byte) *File {
 
 	sFilePath := CStringToString(filePath)
 
-	// TODO: Only some modes are supported by fopen()
-	// https://github.com/elliotchance/c2go/issues/89
-	switch CStringToString(mode) {
+	m := CStringToString(mode)
+	// no-overwrite flag
+	if strings.Contains(m, "x") {
+		m = strings.Replace(m, "x", "", -1)
+		if strings.Contains(m, "w") {
+			// only applies when writing to a file
+			var info os.FileInfo
+			info, err = os.Stat(sFilePath)
+			if info != nil || !os.IsNotExist(err) {
+				setCurrentErrno(EEXIST)
+				return nil
+			}
+		}
+	}
+	// binary flag
+	if strings.Contains(m, "b") {
+		m = strings.Replace(m, "b", "", -1)
+		// no other action needed, we are always using binary mode
+	}
+	switch m {
 	case "r":
 		file, err = os.OpenFile(sFilePath, os.O_RDONLY, 0655)
 	case "r+":