BSON_LIFETIMES(3)

A bson_t <> may contain its data directly or may contain pointers to heap-allocated memory. Overwriting an existing bson_t <> or allowing a stack-allocated bson_t <> to go out of scope may cause a memory leak. A bson_t <> should always be destroyed with bson_destroy() <>.

BSON_T OUT PARAMETERS

A bson_t <> pointer used as an out parameter must point to valid overwritable storage for a new bson_t <> which must be one of:

    1.  Uninitialized storage for a bson_t <>.

    2.  A zero-initialized bson_t <> object.

    3.  A bson_t <> object initialized with BSON_INITIALIZER.

    4.  A bson_t <> object not created with bson_new() <> that was destroyed with bson_destroy() <>.

This can be on the stack:

            bson_t stack_doc = BSON_INITIALIZER;
            example_get_doc (&stack_doc);
            bson_destroy (&stack_doc);

Or on the heap:

            bson_t *heap_doc = bson_malloc (sizeof (bson_t));
            example_get_doc (heap_doc);
            bson_destroy (heap_doc);
            bson_free (heap_doc);

Omitting bson_destroy() <> in either case may cause memory leaks.

Warning:
        Passing a bson_t <> pointer obtained from bson_new() <> as an out parameter will result in a leak of the bson_t <> struct.

                    bson_t *heap_doc = bson_new ();
                    example_get_doc (heap_doc);
                    bson_destroy (heap_doc); // Leaks the `bson_t` struct!

Author
MongoDB, Inc

Copyright
2009-present, MongoDB, Inc.