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BSON_LIFETIMES(3) libbson 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

2017-present, MongoDB, Inc

May 7, 2024 1.27.1