OS_AllocFromHeap

C Specification

#include <nitro/os.h>
void* OS_AllocFromHeap( OSArenaId id, OSHeapHandle heap, u32 size );

void* OS_AllocFromMain( u32 size );
void* OS_AllocFromSubPriv( u32 size );
void* OS_AllocFromMainEx( u32 size );
void* OS_AllocFromITCM( u32 size );
void* OS_AllocFromDTCM( u32 size );
void* OS_AllocFromShared( u32 size );
void* OS_AllocFromWramMain( u32 size );
void* OS_AllocFromWramSub( u32 size );
void* OS_AllocFromSubPrivWram( u32 size );

void* OS_Alloc( u32 size );

Arguments

id Arena ID of the arena associated with the heap from which a region will be reserved
heap Handle of the heap from which a region will be reserved
size Size of the region you want to reserve (bytes)

Return Values

If a region was allocated, the region's start address is returned.
If it was not possible to allocate a region, NULL is returned.

Description

Allocates a memory block from a heap

In OS_AllocFromHeap, you must specify the handle of the allocating heap and the arena ID of the arena that is associated with that heap. The arena is specified with the arena ID (id). For more information, see OS_InitArena().

If OS_CURRENT_HEAP_HANDLE is specified as the heap handle, it will be assumed that the arena's current heap is being specified.

The secure memory domain is aligned at 32 bytes.

OS_AllocFromMain() is the inline function for OS_AllocFromHeap( OS_ARENA_MAIN, OS_CURRENT_HEAP_HANDLE, ... .

OS_AllocFromSubPriv() is the inline function for OS_AllocFromHeap( OS_ARENA_MAIN_SUBPRIV, OS_CURRENT_HEAP_HANDLE, … ).

OS_AllocFromMainEx is the inline function for OS_AllocFromHeap( OS_ARENA_MAINEX, OS_CURRENT_HEAP_HANDLE, ...

OS_AllocFromICTM() is the inline function for OS_AllocFromHeap( OS_ARENA_ITCM, OS_CURRENT_HEAP_HANDLE, ... .

OS_AllocFromDTCM() is the inline function for OS_AllocFromHeap( OS_ARENA_DTCM, OS_CURRENT_HEAP_HANDLE, ... .

OS_AllocFromShared() is the inline function for OS_AllocFromHeap( OS_ARENA_SHARED, OS_CURRENT_HEAP_HANDLE, ... .

OS_AllocFromWramMain() is the inline function for OS_AllocFromHeap( OS_ARENA_WRAM_MAIN, OS_CURRENT_HEAP_HANDLE, … ).

OS_AllocFromWramSub() is the inline function for OS_AllocFromHeap( OS_ARENA_WRAM_SUB, OS_CURRENT_HEAP_HANDLE, … ).

OS_AllocFromSubPrivWram() is the inline function for OS_AllocFromHeap( OS_ARENA_WRAM_SUBPRIV, OS_CURRENT_HEAP_HANDLE, … ).

For ARM9, OS_Alloc is the inline function for OS_AllocFromHeap( OS_ARENA_MAIN, OS_CURRENT_HEAP_HANDLE, … ). For ARM7, OS_Alloc() is the inline function for OS_AllocFromHeap( OS_ARENA_MAIN_SUBPRIV, OS_CURRENT_HEAP_HANDLE, … ).

Caution: When trying to allocate a 0–byte region, DEBUG build stops at ASSERT. In other builds, the operation is undefined.

See Also

OS_InitArena, OS_InitAlloc, OS_CreateHeap, OS_FreeToHeap, OS_FreeAllToHeap

Revision History

07/07/2004 Added caution regarding 0-byte regions.
03/08/2004 Added difference in behavior when called in ARM7 and ARM9.
02/25/2004 Changed the number of arenas from 6 to 9.
01/06/2004 Initial version.