1 files changed, 82 insertions, 0 deletions
diff --git a/tests/memdbg.py b/tests/memdbg.py
new file mode 100644
index 0000000..324d0fd
--- /dev/null
+++ b/tests/memdbg.py
@@ -0,0 +1,82 @@
+import sys
+sys.modules['ssl'] = None
+sys.modules['_hashlib'] = None
+
+
+import traceback
+
+from cffi import api as _api
+_ffi = _api.FFI()
+_ffi.cdef(
+    """
+    void *malloc(size_t size);
+    void free(void *ptr);
+    void *realloc(void *ptr, size_t size);
+
+    int  CRYPTO_set_mem_functions(void *(*m)(size_t),void *(*r)(void *,size_t), void (*f)(void *));
+
+    int backtrace(void **buffer, int size);
+    char **backtrace_symbols(void *const *buffer, int size);
+    void backtrace_symbols_fd(void *const *buffer, int size, int fd);
+    """)
+_api = _ffi.verify(
+    """
+    #include <openssl/crypto.h>
+    #include <stdlib.h>
+    #include <execinfo.h>
+    """, libraries=["crypto"])
+C = _ffi.dlopen(None)
+
+verbose = False
+
+def log(s):
+    if verbose:
+        print(s)
+
+def _backtrace():
+    buf = _ffi.new("void*[]", 64)
+    result = _api.backtrace(buf, len(buf))
+    strings = _api.backtrace_symbols(buf, result)
+    stack = [_ffi.string(strings[i]) for i in range(result)]
+    C.free(strings)
+    return stack
+
+
+@_ffi.callback("void*(*)(size_t)")
+def malloc(n):
+    memory = C.malloc(n)
+    python_stack = traceback.extract_stack(limit=3)
+    c_stack = _backtrace()
+    heap[memory] = [(n, python_stack, c_stack)]
+    log("malloc(%d) -> %s" % (n, memory))
+    return memory
+
+
+@_ffi.callback("void*(*)(void*, size_t)")
+def realloc(p, n):
+    memory = C.realloc(p, n)
+    old = heap.pop(p)
+
+    python_stack = traceback.extract_stack(limit=3)
+    c_stack = _backtrace()
+
+    old.append((n, python_stack, c_stack))
+    heap[memory] = old
+    log("realloc(0x%x, %d) -> %s" % (int(_ffi.cast("int", p)), n, memory))
+    return memory
+
+
+@_ffi.callback("void(*)(void*)")
+def free(p):
+    if p != _ffi.NULL:
+        C.free(p)
+        del heap[p]
+        log("free(0x%x)" % (int(_ffi.cast("int", p)),))
+
+
+if _api.CRYPTO_set_mem_functions(malloc, realloc, free):
+    log('Enabled memory debugging')
+    heap = {}
+else:
+    log('Failed to enable memory debugging')
+    heap = None