malloc newbie question

[gloupygloup]

Hi there,

im trying to build a little things on my own but im not familiar with the PS2SDK.I can compile the HelloWorld sample, make some change, have it running but when i want to make an allocation like :

int *data;
data = malloc(1024);

it compile but the compiler tell me undefined refence for malloc, i think that i miss to link a library but wich one contains the standard stdlib function ?


Thanks in advance !

[ooPo]

Try including malloc.h:

http://cvs.ps2dev.org/cgi-bin/viewcvs.c ... .h?rev=1.5

The function itself would be in the libc library, so make sure you have a -lc on your link line.

[gloupygloup]

Thanks, of course i have added the malloc.h ;-) but not the -lc
im going to test that right away.

Thanks !

[Orion_]

how could the malloc of the standard libc would know where is the psp user ram and so on ??
I don't think this will work.

[gloupygloup]

Orion_ : i have checked your plasma wich work fine dont you alloc anything in memory ?

[Orion_]

no :/
I compute the plasma picture in realtime inside the vram directly.

[gloupygloup]

hmm ok , i m going to do something about that so.

[Klesk]

i suppose the guy who made the gameboy emulator knows how to allocate memory

[sq377]

yea but he also doesn't know english very well.

[ooPo]

Oops, I thought this was a PS2-related question. Sorry. :)

Why not just statically declare the memory?

int data[1024];

[subbie]

Oops, I thought this was a PS2-related question. Sorry. :)

Why not just statically declare the memory?

int data[1024];

Thats all fine for a temp fix but a form of mallocing will be needed.

Anybody know if the systems ram can be directly address or does one need to call on the bios to allocate a useable heap from main memory?

[ooPo]

It may be a little early in the life of the pspdev world to demand things like malloc.

[subbie]

It may be a little early in the life of the pspdev world to demand things like malloc.

Agreed but i'm not going to just sit around and want want want. Questioning then researching will do wonders. :)

[ooPo]

You bring a tear to my eye with such lovely words. :)

[mrbrown]

It may be a little early in the life of the pspdev world to demand things like malloc.

With a little research I found this: http://forums.ps2dev.org/viewtopic.php?p=11133#11133. sceKernelAllocPartitionMemory() looks like malloc() to me.

[gloupygloup]

well i need dynamic allocation since that i have make a couple of emulator and i would like to give it a try to port them into PSP.

Im going to find a way around this problem but it will ugly :D

[gloupygloup]

Just for information i have tried the sceKernelAllocPartitionMemory like that :

Code: Select all

	data = (int*)sceKernelAllocPartitionMemory(sizeof(int)*20);
	
	int	i;

	data[0] = 0xFFFF;

	pgFillvram(0);
	while(1) {
		pgPrint4(1,1,0xFFFF,"TESTING");
		pgScreenFlipV();
	}

when i run my code to the PSP i have black screen but when i comment data[0] = 0xFFFF; i have "TESTING" displayed correctly


I have added this at the end of the startup.s :

Code: Select all

   STUB_START   "SysMemUserForUser",0x40000000,0x00030005 
   STUB_FUNC   0x237DBD4F,sceKernelAllocPartitionMemory 
   STUB_FUNC   0xB6D61D02,sceKernelFreePartitionMemory 
   STUB_FUNC   0x9D9A5BA1,sceKernelGetBlockHeadAddr 
   STUB_END 

[gloupygloup]

Edit : post deleted ( wrong manipulation = double post )

[Shito]

when i run my code to the PSP i have black screen but when i comment data[0] = 0xFFFF; i have "TESTING" displayed correctly

Well then that means that sceKernelAllocPartitionMemory returned null.
Either the memory could not be allocated because there wasn't enough free memory (I highly doubt that ^^), either there was something wrong with the function.
Now *what* is another question. '__'


(and that's all for the most useless and trivial post ever :| )

[gloupygloup]

I wonder if you dont have to give the pointer to your variable to sceKernelAllocPartitionMemory and that it return only OK or ERROR.

im going to have a try

[tonymoon]

Just for information i have tried the sceKernelAllocPartitionMemory like that :

Code: Select all

	data = (int*)sceKernelAllocPartitionMemory(sizeof(int)*20);
	
	int	i;

	data[0] = 0xFFFF;

	pgFillvram(0);
	while(1) {
		pgPrint4(1,1,0xFFFF,"TESTING");
		pgScreenFlipV();
	}

when i run my code to the PSP i have black screen but when i comment data[0] = 0xFFFF; i have "TESTING" displayed correctly


I have added this at the end of the startup.s :

Code: Select all

   STUB_START   "SysMemUserForUser",0x40000000,0x00030005 
   STUB_FUNC   0x237DBD4F,sceKernelAllocPartitionMemory 
   STUB_FUNC   0xB6D61D02,sceKernelFreePartitionMemory 
   STUB_FUNC   0x9D9A5BA1,sceKernelGetBlockHeadAddr 
   STUB_END 

When i run your code my psp got frozen. I try anthor way like this code

Code: Select all

int sceKernelAllocPartitionMemory(void* buf,int size);
void  sceKernelFreePartitionMemory(void* buf);

and I failed too.

[Guest]

Why not just statically declare the memory?

int data[1024];

Thats all fine for a temp fix but a form of mallocing will be needed.

Anybody know if the systems ram can be directly address or does one need to call on the bios to allocate a useable heap from main memory?

Then roll your own dyamic memory allocator. Start with Oopo's suggestion to create your own heap, then write code to alloc, dealloc, realloc, and manage all of it. That will get you going until the time any real allocator is found.

You have no excuse to whine about this. Go forth and code, or wait for deliverance. :)

[gloupygloup]

Hehe,

i have find a way around and im starting getting things to show.
Soon as i got something i will post it here.