Fix SF buf #476953: Bad more for opening file gives bad msg.

If fopen() fails with EINVAL it means that the mode argument is
invalid.  Return the mode in the error message instead of the
filename.

diff --git a/Lib/test/test_file.py b/Lib/test/test_file.py
index a85e07cacf7a4982783aba0dd0c1abdfc0d73e07..cb1bdce08e0d8b35d210b5a6cab3ac97d5a0760e 100644 (file)
--- a/Lib/test/test_file.py
+++ b/Lib/test/test_file.py
@@ -46,4 +46,15 @@ else:
     print "writelines accepted sequence of non-string objects"
 f.close()
 
+# verify that we get a sensible error message for bad made argument
+bad_mode = "qwerty"
+try:
+    open(TESTFN, bad_mode)
+except IOError, msg:
+    s = str(msg)
+    if s.find(TESTFN) != -1 or s.find(bad_mode) == -1:
+        print "bad error message for invalid mode: %s" % s
+else:
+    print "no error for invalid mode: %s" % bad_mode
+
 os.unlink(TESTFN)

diff --git a/Objects/fileobject.c b/Objects/fileobject.c
index ebccc845cc25c86fe9d5a3467b733ca545906a06..9284185be637cb306d1ddafcddc30480dc3236f6 100644 (file)
--- a/Objects/fileobject.c
+++ b/Objects/fileobject.c
@@ -121,13 +121,17 @@ open_the_file(PyFileObject *f, char *name, char *mode)
        if (f->f_fp == NULL) {
 #ifdef NO_FOPEN_ERRNO
                /* Metroworks only, not testable, so unchanged */
-               if ( errno == 0 ) {
+               if (errno == 0) {
                        PyErr_SetString(PyExc_IOError, "Cannot open file");
                        Py_DECREF(f);
                        return NULL;
                }
 #endif
-               PyErr_SetFromErrnoWithFilename(PyExc_IOError, name);
+               if (errno == EINVAL)
+                       PyErr_Format(PyExc_IOError, "invalid argument: %s",
+                                    mode);
+               else
+                       PyErr_SetFromErrnoWithFilename(PyExc_IOError, name);
                f = NULL;
        }
        return (PyObject *)f;