GodMode9/arm9/source/fatfs/ramdrive.c

#include "ramdrive.h"
#include "unittype.h"
#include "memmap.h"

static u8* ramdrv_buffer = NULL;
static u32 ramdrv_size = 0;

int ReadRamDriveSectors(void* buffer, u32 sector, u32 count) {
    u64 offset = sector * 0x200;
    u64 btr = count * 0x200;
    if (!ramdrv_buffer) return -1;
    if ((offset + btr) > ramdrv_size) return -1;
    memcpy(buffer, ramdrv_buffer + offset, btr);
    return 0;
}
int WriteRamDriveSectors(const void* buffer, u32 sector, u32 count) {
    u64 offset = sector * 0x200;
    u64 btw = count * 0x200;
    if (!ramdrv_buffer) return -1;
    if ((offset + btw) > ramdrv_size) return -1;
    memcpy(ramdrv_buffer + offset, buffer, btw);
    return 0;
}

u64 GetRamDriveSize(void) {
    return ramdrv_size;
}

void InitRamDrive(void) {
    ramdrv_buffer = (u8*) __RAMDRV_ADDR;
    ramdrv_size = (IS_O3DS ? __RAMDRV_END : __RAMDRV_END_N) - __RAMDRV_ADDR;
}