[Mesa-dev] [PATCH 1/3] util/tests: Expand collision test for hash table

[Emil Velikov]

Hi Thomas,

On 11/04/15 23:25, Thomas Helland wrote:
> Add a test to exercise a worst case collision scenario
> that may cause us to not be able to find an empty
> slot in the table even though it is not full.
> This hits the bug in my last revision of the series
> converting the hash table to quadratic probing.
> 
> Signed-off-by: Thomas Helland <thomashelland90 at gmail.com>
> ---
>  src/util/tests/hash_table/collision.c | 14 ++++++++++++++
>  1 file changed, 14 insertions(+)
> 
> diff --git a/src/util/tests/hash_table/collision.c b/src/util/tests/hash_table/collision.c
> index 69a4c29..ba284d8 100644
> --- a/src/util/tests/hash_table/collision.c
> +++ b/src/util/tests/hash_table/collision.c
> @@ -89,6 +89,20 @@ main(int argc, char **argv)
>     entry2 = _mesa_hash_table_search_pre_hashed(ht, bad_hash, str2);
>     assert(entry2->key == str2);
>  
> +
> +   _mesa_hash_table_destroy(ht, NULL);
> +
> +   /* Try inserting multiple items with the same hash
> +    * This exercises a worst case scenario where we might fail to find
> +    * an empty slot in the table, even though there is free space
> +    */
> +   ht = _mesa_hash_table_create(NULL, NULL, _mesa_key_string_equal);
> +   for (i = 0; i < 100; i++) {
> +      char *key = malloc(10);
> +      sprintf(key, "spam%d", i);
> +      assert(_mesa_hash_table_insert_pre_hashed(ht, bad_hash, key, NULL) != NULL);
Please don't include code in asserts - it won't exist for non-debug builds.

-Emil