From 772dfd5dcb0e59459a8ff4924ff5cb2383b7c5d3 Mon Sep 17 00:00:00 2001
From: Zackery Spytz <zspytz@gmail.com>
Date: Sun, 7 Jun 2020 17:47:11 -0600
Subject: [PATCH 1/2] Fix the error handling for the PyObject_GetBuffer() calls
 in pybuffer.i

Closes #1640.
---
 Lib/python/pybuffer.i | 24 +++++++++++-------------
 1 file changed, 11 insertions(+), 13 deletions(-)

diff --git a/Lib/python/pybuffer.i b/Lib/python/pybuffer.i
index 577eb69c8..2fdaa6d6e 100644
--- a/Lib/python/pybuffer.i
+++ b/Lib/python/pybuffer.i
@@ -17,13 +17,13 @@
   int res; Py_ssize_t size = 0; void *buf = 0;
   Py_buffer view;
   res = PyObject_GetBuffer($input, &view, PyBUF_WRITABLE);
-  size = view.len;
-  buf = view.buf;
-  PyBuffer_Release(&view);
   if (res < 0) {
     PyErr_Clear();
     %argument_fail(res, "(TYPEMAP, SIZE)", $symname, $argnum);
   }
+  size = view.len;
+  buf = view.buf;
+  PyBuffer_Release(&view);
   $1 = ($1_ltype) buf;
   $2 = ($2_ltype) (size/sizeof($*1_type));
 }
@@ -47,12 +47,12 @@
   int res; void *buf = 0;
   Py_buffer view;
   res = PyObject_GetBuffer($input, &view, PyBUF_WRITABLE);
-  buf = view.buf;
-  PyBuffer_Release(&view);
   if (res < 0) {
     PyErr_Clear();
     %argument_fail(res, "(TYPEMAP)", $symname, $argnum);
   }
+  buf = view.buf;
+  PyBuffer_Release(&view);
   $1 = ($1_ltype) buf;
 }
 %enddef
@@ -76,13 +76,13 @@
   int res; Py_ssize_t size = 0; const void *buf = 0;
   Py_buffer view;
   res = PyObject_GetBuffer($input, &view, PyBUF_CONTIG_RO);
-  size = view.len;
-  buf = view.buf;
-  PyBuffer_Release(&view);
   if (res < 0) {
     PyErr_Clear();
     %argument_fail(res, "(TYPEMAP, SIZE)", $symname, $argnum);
   }
+  size = view.len;
+  buf = view.buf;
+  PyBuffer_Release(&view);
   $1 = ($1_ltype) buf;
   $2 = ($2_ltype) (size / sizeof($*1_type));
 }
@@ -108,14 +108,12 @@
   int res; const void *buf = 0;
   Py_buffer view;
   res = PyObject_GetBuffer($input, &view, PyBUF_CONTIG_RO);
-  buf = view.buf;
-  PyBuffer_Release(&view);
   if (res < 0) {
+    PyErr_Clear();
     %argument_fail(res, "(TYPEMAP)", $symname, $argnum);
   }
+  buf = view.buf;
+  PyBuffer_Release(&view);
   $1 = ($1_ltype) buf;
 }
 %enddef
-
-
-

From c4c8751892b9f50a45d724e7785e4659aeeb4cf7 Mon Sep 17 00:00:00 2001
From: Zackery Spytz <zspytz@gmail.com>
Date: Mon, 15 Jun 2020 01:33:59 -0600
Subject: [PATCH 2/2] Add tests.

---
 .../python/python_pybuffer_runme.py           | 24 +++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/Examples/test-suite/python/python_pybuffer_runme.py b/Examples/test-suite/python/python_pybuffer_runme.py
index 8ecdb523b..be73b0bad 100644
--- a/Examples/test-suite/python/python_pybuffer_runme.py
+++ b/Examples/test-suite/python/python_pybuffer_runme.py
@@ -44,3 +44,27 @@ else:
     buf3 = bytearray(b"hello")
     python_pybuffer.title1(buf3)
     check(buf3 == b"Hello")
+
+    try:
+        python_pybuffer.func1(1)
+        raise RuntimeError, "should throw TypeError"
+    except TypeError, e:
+        check("(char *buf1, int len)" in str(e))
+
+    try:
+        python_pybuffer.func2(1)
+        raise RuntimeError, "should throw TypeError"
+    except TypeError, e:
+        check("(char *buf2)" in str(e))
+
+    try:
+        python_pybuffer.func3(1)
+        raise RuntimeError, "should throw TypeError"
+    except TypeError, e:
+        check("(const char *buf3, int len)" in str(e))
+
+    try:
+        python_pybuffer.func4(1)
+        raise RuntimeError, "should throw TypeError"
+    except TypeError, e:
+        check("(const char *buf4)" in str(e))