malloc and casts

Manu Abraham abraham.manu@gmail.com
Wed Aug 17 14:25:00 GMT 2005


Andrew Hardy wrote:

>I don't really undrstand what you're trying to achieve, but it looks a bit
>  
>

I am trying to parse a bitstream, with minimal CPU usage, ie without 
using too many a malloc().

>suspicious that you have pointers as part of your structs, this may give
>issues when you cast if you think you have structs wholely within structs.
>
>  
>

I think this was the problem i have been facing..

>Would something like this help??
>
>char *ptr;
>
>// where storage contains what you want in enough space to coopy it out
>into your structs.
>ptr = storage;
>
>memcpy(somestruct, ptr, sizeof(somestruct));
>ptr += sizeof(somestruct);
>
>memcpy(somestruct, ptr, sizeof(somestruct));
>ptr += sizeof(somestruct);
>
>memcpy(somestruct, ptr, sizeof(somestruct));
>ptr += sizeof(somestruct);
>
>etc...
>
>where your structures don't include pointers and where somestruct is the
>current of a number structures or if you require current of a number of
>substructures that you require to have in one struct.
>
>  
>

Hmm, You mean to say, use the structs without the pointers ?

Thanks,
Manu



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