On 08/05/2016 12:55 PM, Mark J Twain wrote:
I use malloc to allocate some memory, then free it later. For monitoring
purposes, I would like to know how much is free'ed by free by just
knowing the object. Or, rather, given a ptr allocated by malloc, bet the
block size it allocated from the ptr alone.
Some C compilers have special intrinsics and such for this, does D have
any ability? If not, any hacks? I just need something that works.
malloc stores the allocation size and other information right before the
pointer that it returns. You can do better than I do below if you know
the exact objects that it stores there. And of course you don't need a
struct. I just liked the property idea there. :)
import std.stdio;
import core.stdc.stdlib;
struct AllocatedMemory {
void *p;
alias SizeType = size_t; // perhaps ulong?
@property SizeType size() {
return *cast(SizeType*)(p - SizeType.sizeof);
}
}
void myFree(void * p) {
auto a = AllocatedMemory(p);
writefln("Freeing something like 0x%x bytes", a.size);
}
void main() {
auto p = malloc(0x12345);
myFree(p);
}
Prints:
Freeing something like 0x12351 bytes
Ali
