On 3/17/10 3:39 PM, "Graham Leggett" <[email protected]> wrote:
>On 18 Mar 2010, at 12:18 AM, Ivan Novick wrote:
>> I am doing some testing with APR version 1.2.12
>>
>> When adding to a hash table using apr_hash_set ... If memory can not
>> be
>> allocated what is the expected behavior?
>>
>> I am seeing apr_hash_set calls expand_array.
>>
>> expand_array core dumps if memory can not be allocated.
>>
>> Is this expected? Is there a way to get an error code for a failed
>> insert
>> to a table rather than a coredump?
>This is definitely wrong, APR should return APR_ENOMEM if memory
>cannot be allocated.
>More specifically, the APR pools code gives the caller (you) the
>choice of behaviour when the memory allocation fails. You can choose
>to have APR call a function of your choice, or you can choose APR to
>return APR_ENOMEM.
>httpd chooses to call a function that terminates the server child when
>out of memory, and as a result httpd makes no attempt to cater for out
>of memory conditions, but other callers of APR don't have to, and APR
>itself should definitely respect APR_ENOMEM.
When you say this wrong, do you mean the code is wrong or that the analysis of
what the code does is wrong?
In the code below, if alloc_array returns NULL, this should core dump. In fact
this code returns void so I don't see how it could be passing back information
about failed memory allocation with a return code.
Cheers,
Ivan
/*
* Expanding a hash table
*/
static void expand_array(apr_hash_t *ht)
{
apr_hash_index_t *hi;
apr_hash_entry_t **new_array;
unsigned int new_max;
new_max = ht->max * 2 + 1;
new_array = alloc_array(ht, new_max);
for (hi = apr_hash_first(NULL, ht); hi; hi = apr_hash_next(hi)) {
unsigned int i = hi->this->hash & new_max;
hi->this->next = new_array[i];
new_array[i] = hi->this;
}
ht->array = new_array;
ht->max = new_max;
}
