Use correct function name to PyArg_ParseTuple("is_package").

Fix off-by-1 error in normalize_line_endings():
  when *p == '\0' the NUL was copied into q and q was auto-incremented,
  the loop was broken out of,
  then a newline was appended followed by a NUL.
  So the function, in effect, was strcpy() but added two extra chars
  which was caught by obmalloc in debug mode, since there was only
  room for 1 additional newline.

Get test working under regrtest (added test_main).

Lib/test/test_zipimport.py

@@ -186,6 +186,9 @@ class CompressedZipImportTestCase(UncompressedZipImportTestCase):
     compression = ZIP_DEFLATED
 
 
-if __name__ == "__main__":
+def test_main():
     test_support.run_unittest(UncompressedZipImportTestCase)
     test_support.run_unittest(CompressedZipImportTestCase)
+
+if __name__ == "__main__":
+    test_main()

Modules/zipimport.c

@@ -371,7 +371,7 @@ zipimporter_is_package(PyObject *obj, PyObject *args)
 	char *fullname;
 	enum module_info mi;
 
-	if (!PyArg_ParseTuple(args, "s:zipimporter.find_module",
+	if (!PyArg_ParseTuple(args, "s:zipimporter.is_package",
 			      &fullname))
 		return NULL;
 
@@ -947,7 +947,7 @@ normalize_line_endings(PyObject *source)
 		return NULL;
 	}
 	/* replace "\r\n?" by "\n" */
-	for (q = buf;;) {
+	for (q = buf; *p != '\0'; p++) {
 		if (*p == '\r') {
 			*q++ = '\n';
 			if (*(p + 1) == '\n')
@@ -955,9 +955,6 @@ normalize_line_endings(PyObject *source)
 		}
 		else
 			*q++ = *p;
-		if (*p == '\0')
-			break;
-		p++;
 	}
 	*q++ = '\n';  /* add trailing \n */
 	*q = '\0';