X-Git-Url: http://git.efficios.com/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fcommon%2Fdynamic-array.h;h=71cf9af189c97a8ef6d30ffabce1f9ba0946928b;hp=208dd1956b41263df7f8336605f22e082bff21ac;hb=2463b7879c00298daa79744cdaae82ac061a4ed8;hpb=ab5be9fa2eb5ba9600a82cd18fd3cfcbac69169a diff --git a/src/common/dynamic-array.h b/src/common/dynamic-array.h index 208dd1956..71cf9af18 100644 --- a/src/common/dynamic-array.h +++ b/src/common/dynamic-array.h @@ -56,6 +56,25 @@ void *lttng_dynamic_array_get_element(const struct lttng_dynamic_array *array, return array->buffer.data + (element_index * array->element_size); } +/* + * Set the array's element count to new_element_count. Any added element will + * be zeroed. + * + * Be careful to expand the array's element count _before_ calling out external + * APIs (e.g. read(3)) which may populate the buffer as setting the element + * count after will zero-out the result of the operation. + * + * Shrinking an array does not zero the old content. If the buffer may contain + * sensititve information, it must be cleared manually _before_ changing the + * size. + * + * NOTE: It is striclty _invalid_ to access memory after _size_, regardless + * of prior calls to set_capacity(). + */ +LTTNG_HIDDEN +int lttng_dynamic_array_set_count(struct lttng_dynamic_array *array, + size_t new_element_count); + /* * Add an element to the end of a dynamic array. The array's element count is * increased by one and its underlying capacity is adjusted automatically. @@ -121,6 +140,23 @@ void *lttng_dynamic_pointer_array_get_pointer( return *element; } +/* + * Returns the pointer at index `index`, sets the array slot to NULL. Does not + * run the destructor. + */ + +static inline +void *lttng_dynamic_pointer_array_steal_pointer( + struct lttng_dynamic_pointer_array *array, size_t index) +{ + void **p_element = lttng_dynamic_array_get_element(&array->array, index); + void *element = *p_element; + + *p_element = NULL; + + return element; +} + /* * Add a pointer to the end of a dynamic pointer array. The array's element * count is increased by one and its underlying capacity is adjusted