bpo-25720: curses: Fix check for whether WINDOW is a pad

Include/py_curses.h

@@ -7,22 +7,17 @@
 ** On Mac OS X 10.2 [n]curses.h and stdlib.h use different guards
 ** against multiple definition of wchar_t.
 */
-#ifdef	_BSD_WCHAR_T_DEFINED_
+#ifdef  _BSD_WCHAR_T_DEFINED_
 #define _WCHAR_T
 #endif
-
-/* the following define is necessary for OS X 10.6; without it, the
-   Apple-supplied ncurses.h sets NCURSES_OPAQUE to 1, and then Python
-   can't get at the WINDOW flags field. */
-#define NCURSES_OPAQUE 0
 #endif /* __APPLE__ */
 
 #ifdef __FreeBSD__
 /*
 ** On FreeBSD, [n]curses.h and stdlib.h/wchar.h use different guards
 ** against multiple definition of wchar_t and wint_t.
 */
-#ifdef	_XOPEN_SOURCE_EXTENDED
+#ifdef  _XOPEN_SOURCE_EXTENDED
 #ifndef __FreeBSD_version
 #include <osreldate.h>
 #endif
@@ -44,6 +39,15 @@
 #endif
 #endif
 
+#if !defined(HAVE_CURSES_IS_PAD) && !defined(WINDOW_HAS_FLAGS)
+/* If ncurses doesn't have both is_pad function and _flags field of WINDOW,
+   there is no method to check whether WINDOW is a pad.  Therefore, add the
+   definitions to make WINDOW to non-opaque type before including [n]curses.h.
+*/
+#define NCURSES_OPAQUE 0
+#define WINDOW_HAS_FLAGS 1
+#endif
+
 #ifdef HAVE_NCURSES_H
 #include <ncurses.h>
 #else
@@ -57,9 +61,6 @@
 #ifdef HAVE_NCURSES_H
 /* configure was checking <curses.h>, but we will
    use <ncurses.h>, which has all these features. */
-#ifndef WINDOW_HAS_FLAGS
-#define WINDOW_HAS_FLAGS 1
-#endif
 #ifndef MVWDELCH_IS_EXPRESSION
 #define MVWDELCH_IS_EXPRESSION 1
 #endif
@@ -74,12 +75,12 @@ extern "C" {
 /* Type declarations */
 
 typedef struct {
-	PyObject_HEAD
-	WINDOW *win;
-	char *encoding;
+    PyObject_HEAD
+    WINDOW *win;
+    char *encoding;
 } PyCursesWindowObject;
 
-#define PyCursesWindow_Check(v)	 (Py_TYPE(v) == &PyCursesWindow_Type)
+#define PyCursesWindow_Check(v)  (Py_TYPE(v) == &PyCursesWindow_Type)
 
 #define PyCurses_CAPSULE_NAME "_curses._C_API"
 

Misc/NEWS.d/next/Library/2017-06-24-13-47-00.bpo-25720.iEVYvL.rst

@@ -0,0 +1 @@
+curses: Fix check for whether WINDOW is a pad.

Modules/_cursesmodule.c

@@ -928,6 +928,12 @@ int py_mvwdelch(WINDOW *w, int y, int x)
 }
 #endif
 
+#if defined(HAVE_CURSES_IS_PAD)
+#define py_is_pad(win)      is_pad(win)
+#elif defined(WINDOW_HAS_FLAGS)
+#define py_is_pad(win)      ((win) ? ((win)->_flags & _ISPAD) != 0 : FALSE)
+#endif
+
 /* chgat, added by Fabian Kreutz <fabian.kreutz at gmx.net> */
 
 static PyObject *
@@ -1067,8 +1073,8 @@ PyCursesWindow_EchoChar(PyCursesWindowObject *self, PyObject *args)
     if (!PyCurses_ConvertToChtype(self, temp, &ch))
         return NULL;
 
-#ifdef WINDOW_HAS_FLAGS
-    if (self->win->_flags & _ISPAD)
+#ifdef py_is_pad
+    if (py_is_pad(self->win))
         return PyCursesCheckERR(pechochar(self->win, ch | attr),
                                 "echochar");
     else
@@ -1602,41 +1608,42 @@ PyCursesWindow_NoOutRefresh(PyCursesWindowObject *self, PyObject *args)
     int pminrow,pmincol,sminrow,smincol,smaxrow,smaxcol;
     int rtn;
 
-#ifndef WINDOW_HAS_FLAGS
+#ifndef py_is_pad
     if (0)
 #else
-        if (self->win->_flags & _ISPAD)
-#endif
-        {
-            switch(PyTuple_Size(args)) {
-            case 6:
-                if (!PyArg_ParseTuple(args,
-                                      "iiiiii;" \
-                                      "pminrow,pmincol,sminrow,smincol,smaxrow,smaxcol",
-                                      &pminrow, &pmincol, &sminrow,
-                                      &smincol, &smaxrow, &smaxcol))
-                    return NULL;
-                Py_BEGIN_ALLOW_THREADS
-                rtn = pnoutrefresh(self->win,
-                                   pminrow, pmincol, sminrow,
-                                   smincol, smaxrow, smaxcol);
-                Py_END_ALLOW_THREADS
-                return PyCursesCheckERR(rtn, "pnoutrefresh");
-            default:
-                PyErr_SetString(PyCursesError,
-                                "noutrefresh() called for a pad "
-                                "requires 6 arguments");
-                return NULL;
-            }
-        } else {
-            if (!PyArg_ParseTuple(args, ":noutrefresh"))
+    if (py_is_pad(self->win))
+#endif
+    {
+        switch(PyTuple_Size(args)) {
+        case 6:
+            if (!PyArg_ParseTuple(args,
+                                  "iiiiii;" \
+                                  "pminrow,pmincol,sminrow,smincol,smaxrow,smaxcol",
+                                  &pminrow, &pmincol, &sminrow,
+                                  &smincol, &smaxrow, &smaxcol))
                 return NULL;
 
             Py_BEGIN_ALLOW_THREADS
-            rtn = wnoutrefresh(self->win);
+            rtn = pnoutrefresh(self->win,
+                               pminrow, pmincol, sminrow,
+                               smincol, smaxrow, smaxcol);
             Py_END_ALLOW_THREADS
-            return PyCursesCheckERR(rtn, "wnoutrefresh");
+            return PyCursesCheckERR(rtn, "pnoutrefresh");
+        default:
+            PyErr_SetString(PyCursesError,
+                            "noutrefresh() called for a pad "
+                            "requires 6 arguments");
+            return NULL;
         }
+    } else {
+        if (!PyArg_ParseTuple(args, ":noutrefresh"))
+            return NULL;
+
+        Py_BEGIN_ALLOW_THREADS
+        rtn = wnoutrefresh(self->win);
+        Py_END_ALLOW_THREADS
+        return PyCursesCheckERR(rtn, "wnoutrefresh");
+    }
 }
 
 static PyObject *
@@ -1765,40 +1772,41 @@ PyCursesWindow_Refresh(PyCursesWindowObject *self, PyObject *args)
     int pminrow,pmincol,sminrow,smincol,smaxrow,smaxcol;
     int rtn;
 
-#ifndef WINDOW_HAS_FLAGS
+#ifndef py_is_pad
     if (0)
 #else
-        if (self->win->_flags & _ISPAD)
-#endif
-        {
-            switch(PyTuple_Size(args)) {
-            case 6:
-                if (!PyArg_ParseTuple(args,
-                                      "iiiiii;" \
-                                      "pminrow,pmincol,sminrow,smincol,smaxrow,smaxcol",
-                                      &pminrow, &pmincol, &sminrow,
-                                      &smincol, &smaxrow, &smaxcol))
-                    return NULL;
-
-                Py_BEGIN_ALLOW_THREADS
-                rtn = prefresh(self->win,
-                               pminrow, pmincol, sminrow,
-                               smincol, smaxrow, smaxcol);
-                Py_END_ALLOW_THREADS
-                return PyCursesCheckERR(rtn, "prefresh");
-            default:
-                PyErr_SetString(PyCursesError,
-                                "refresh() for a pad requires 6 arguments");
-                return NULL;
-            }
-        } else {
-            if (!PyArg_ParseTuple(args, ":refresh"))
+    if (py_is_pad(self->win))
+#endif
+    {
+        switch(PyTuple_Size(args)) {
+        case 6:
+            if (!PyArg_ParseTuple(args,
+                                  "iiiiii;" \
+                                  "pminrow,pmincol,sminrow,smincol,smaxrow,smaxcol",
+                                  &pminrow, &pmincol, &sminrow,
+                                  &smincol, &smaxrow, &smaxcol))
                 return NULL;
+
             Py_BEGIN_ALLOW_THREADS
-            rtn = wrefresh(self->win);
+            rtn = prefresh(self->win,
+                           pminrow, pmincol, sminrow,
+                           smincol, smaxrow, smaxcol);
             Py_END_ALLOW_THREADS
             return PyCursesCheckERR(rtn, "prefresh");
+        default:
+            PyErr_SetString(PyCursesError,
+                            "refresh() for a pad requires 6 arguments");
+            return NULL;
         }
+    } else {
+        if (!PyArg_ParseTuple(args, ":refresh"))
+            return NULL;
+
+        Py_BEGIN_ALLOW_THREADS
+        rtn = wrefresh(self->win);
+        Py_END_ALLOW_THREADS
+        return PyCursesCheckERR(rtn, "prefresh");
+    }
 }
 
 static PyObject *
@@ -1834,8 +1842,8 @@ PyCursesWindow_SubWin(PyCursesWindowObject *self, PyObject *args)
     }
 
     /* printf("Subwin: %i %i %i %i   \n", nlines, ncols, begin_y, begin_x); */
-#ifdef WINDOW_HAS_FLAGS
-    if (self->win->_flags & _ISPAD)
+#ifdef py_is_pad
+    if (py_is_pad(self->win))
         win = subpad(self->win, nlines, ncols, begin_y, begin_x);
     else
 #endif

configure

@@ -15957,6 +15957,36 @@ $as_echo "#define MVWDELCH_IS_EXPRESSION 1" >>confdefs.h
 
 fi
 
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for is_pad" >&5
+$as_echo_n "checking for is_pad... " >&6; }
+cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+#include <curses.h>
+int
+main ()
+{
+
+    bool b;
+    WINDOW *w;
+    b = is_pad(w);
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+
+$as_echo "#define HAVE_CURSES_IS_PAD 1" >>confdefs.h
+
+   { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+$as_echo "yes" >&6; }
+else
+  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
+$as_echo "no" >&6; }
+
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+
 { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether WINDOW has _flags" >&5
 $as_echo_n "checking whether WINDOW has _flags... " >&6; }
 if ${ac_cv_window_has_flags+:} false; then :

configure.ac

@@ -5044,6 +5044,18 @@ then
   [Define if mvwdelch in curses.h is an expression.])
 fi
 
+AC_MSG_CHECKING(for is_pad)
+AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#include <curses.h>]], [[
+    bool b;
+    WINDOW *w;
+    b = is_pad(w);
+  ]])],
+  [AC_DEFINE(HAVE_CURSES_IS_PAD, 1,
+             [Define if you have the 'is_pad' function or macro.])
+   AC_MSG_RESULT(yes)],
+  [AC_MSG_RESULT(no)]
+)
+
 AC_MSG_CHECKING(whether WINDOW has _flags)
 AC_CACHE_VAL(ac_cv_window_has_flags,
 AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#include <curses.h>]], [[

pyconfig.h.in

@@ -149,6 +149,9 @@
 /* Define to 1 if you have the <curses.h> header file. */
 #undef HAVE_CURSES_H
 
+/* Define if you have the 'is_pad' function or macro. */
+#undef HAVE_CURSES_IS_PAD
+
 /* Define if you have the 'is_term_resized' function. */
 #undef HAVE_CURSES_IS_TERM_RESIZED