realloc

["Fisk, Kevin" <kf...@sbcglobal.net>]

Is there any concept of reallocation to change the size of allocated memory inside a pool.  If there is no data past the end of the allocated memory in the pool, it shouldn't require me to allocate a new buffer and transfer all of the data to the new buffer.  I also then would have to have a pool more than double the size of the largest buffer I plan to extend.
 
Am I missing something?
 
Thanks,
Kevin Fisk

Re: realloc

["William A. Rowe, Jr." <wr...@rowe-clan.net>]

At 05:48 PM 10/8/2003, Fisk, Kevin wrote:
>Is there any concept of reallocation to change the size of allocated memory inside a pool.  If there is no data past the end of the allocated memory in the pool, it shouldn't require me to allocate a new buffer and transfer all of the data to the new buffer.  I also then would have to have a pool more than double the size of the largest buffer I plan to extend.

Kevin, your request isn't unreasonable (in fact apr_psprintf() does just
that) and we should extend this, externally.

Note that it is quite unlikely to be useful if you have
any APR calls using the same pool (or pool-based object
in the same pool) while you are constructing your buffer
object, or if you expect to resize-downwards the pool
buffer.  Note that pools are designed for objects to
expand, and although they could conceivably compact, the
idea of pools is never to be a dynamic grow/shrink schema.

I think most developers would agree that using this facility
internally to the library should have been a hint that it
is greatly desired externally to apr.

The benefit of pools is alloc once and forget.  This is
whey they have better performance than malloc/free.

Bill