Branch data     Line data    Source code

       1                 :             : #include "mem.h"
       2                 :             : #include "mem_internal.h"
       3                 :             : 
       4                 :             : /**
       5                 :             :  * @brief Return a writable raw pointer without checking the element type
       6                 :             :  *
       7                 :             :  * This helper returns a writable pointer without performing any element-type
       8                 :             :  * verification. It is meant for low-level code that already knows what lives in
       9                 :             :  * the descriptor and only needs the library to reject the most obviously broken
      10                 :             :  * descriptor states before exposing the buffer.
      11                 :             :  *
      12                 :             :  * In practice, that means the function still checks for a `NULL` descriptor, a
      13                 :             :  * zero element size, reserved bytes with no backing pointer, and non-zero
      14                 :             :  * logical length with a `NULL` data pointer. It does not compare the descriptor
      15                 :             :  * against an expected element type, and it does not rewrite `is_string` or
      16                 :             :  * `string_length`
      17                 :             :  *
      18                 :             :  * On success the returned pointer is the descriptor's live @ref memory::data
      19                 :             :  * pointer, not a copy and not a detached view. A read-only raw view obtained
      20                 :             :  * from the same descriptor exposes the same backing storage. The pointer stays
      21                 :             :  * valid only until an operation that may replace or release the descriptor
      22                 :             :  * storage, such as @ref mem_resize, @ref mem_delete, or a descriptor-copy or
      23                 :             :  * concat operation that targets this descriptor
      24                 :             :  *
      25                 :             :  * @param memory_object Pointer to a descriptor
      26                 :             :  * @return Writable storage pointer on success. `NULL` when the descriptor is too broken to expose safely
      27                 :             :  */
      28                 :        2553 : void *mem_raw_data_writable(memory *memory_object)
      29                 :             : {
      30         [ +  + ]:        2553 :         if(memory_object == NULL)
      31                 :             :         {
      32                 :           1 :                 report("Memory management; Descriptor is NULL");
      33                 :           1 :                 return(NULL);
      34                 :             :         }
      35                 :             : 
      36         [ +  + ]:        2552 :         if(memory_object->single_element_size == 0)
      37                 :             :         {
      38                 :           1 :                 report("Memory management; Descriptor element size is zero (uninitialized)");
      39                 :           1 :                 return(NULL);
      40                 :             :         }
      41                 :             : 
      42   [ +  +  +  + ]:        2551 :         if(memory_object->data == NULL && memory_object->actually_allocated_bytes > 0)
      43                 :             :         {
      44                 :           1 :                 report("Memory management; Descriptor has reserved bytes with NULL data pointer");
      45                 :           1 :                 return(NULL);
      46                 :             :         }
      47                 :             : 
      48   [ +  -  +  + ]:        2550 :         if(memory_object->length > 0 && memory_object->data == NULL)
      49                 :             :         {
      50                 :           1 :                 report("Memory management; Descriptor has non-zero length with NULL data pointer");
      51                 :           1 :                 return(NULL);
      52                 :             :         }
      53                 :             : 
      54                 :        2549 :         return(memory_object->data);
      55                 :             : }