stdlib/os: add close

Signed-off-by: Sebastien Binet <binet@cern.ch>

Author: sbinet

stdlib/os/os.go

@@ -46,6 +46,7 @@ func init() {
 
 	methods := []*py.Method{
 		py.MustNewMethod("_exit", _exit, 0, "Immediate program termination."),
+		py.MustNewMethod("close", closefd, 0, closefd_doc),
 		py.MustNewMethod("fdopen", fdopen, 0, fdopen_doc),
 		py.MustNewMethod("getcwd", getCwd, 0, "Get the current working directory"),
 		py.MustNewMethod("getcwdb", getCwdb, 0, "Get the current working directory in a byte slice"),
@@ -98,6 +99,35 @@ func getEnvVariables() py.StringDict {
 	return dict
 }
 
+const closefd_doc = `Close a file descriptor`
+
+func closefd(self py.Object, args py.Tuple, kwargs py.StringDict) (py.Object, error) {
+	var (
+		pyfd py.Object
+	)
+	err := py.ParseTupleAndKeywords(args, kwargs, "i", []string{"fd"}, &pyfd)
+	if err != nil {
+		return nil, err
+	}
+
+	var (
+		fd   = uintptr(pyfd.(py.Int))
+		name = strconv.Itoa(int(fd))
+	)
+
+	f := os.NewFile(fd, name)
+	if f == nil {
+		return nil, py.ExceptionNewf(py.OSError, "Bad file descriptor")
+	}
+
+	err = f.Close()
+	if err != nil {
+		return nil, err
+	}
+
+	return py.None, nil
+}
+
 const fdopen_doc = `# Supply os.fdopen()`
 
 func fdopen(self py.Object, args py.Tuple, kwargs py.StringDict) (py.Object, error) {

stdlib/os/testdata/test.py

@@ -118,6 +118,17 @@
     else:
         print("os."+k+": [OK]")
 
+## close
+import tempfile
+fd, tmp = tempfile.mkstemp()
+os.close(fd=fd)
+os.remove(tmp)
+try:
+    os.close(-1)
+    print("closing a bad file descriptor should have failed")
+except Exception as e:
+    print("caught: %s [OK]" % e)
+
 ## fdopen
 import tempfile
 fd, tmp = tempfile.mkstemp()

stdlib/os/testdata/test_golden.txt

@@ -24,6 +24,7 @@ os.pathsep: [OK]
 os.linesep: [OK]
 os.devnull: [OK]
 os.altsep: [OK]
+caught: OSError: 'Bad file descriptor' [OK]
 caught: SystemError - no such file or directory [OK]
 caught: FileExistsError [OK]
 caught: SystemError - directory not empty [OK]