Expose SRAM pointers for frontends that manage save data their own way (#1643)

* Add a clarifying comment

- In case it saves some poor bastard hours of fruitless work

* Expose GBA and NDS save memory

- Add GetSaveMemory and GetSaveMemoryLength functions
- Where unsupported, they return null and zero

1 files changed, 18 insertions, 0 deletions

diff --git a/src/GBACart.h b/src/GBACart.h
index 8610714..3357d22 100644
--- a/src/GBACart.h
+++ b/src/GBACart.h
@@ -49,6 +49,9 @@ public:
 

     virtual u8 SRAMRead(u32 addr);

     virtual void SRAMWrite(u32 addr, u8 val);

+

+    virtual u8* GetSaveMemory() const;

+    virtual u32 GetSaveMemoryLength() const;

 };

 

 // CartGame -- regular retail game cart (ROM, SRAM)

@@ -74,6 +77,8 @@ public:
     virtual u8 SRAMRead(u32 addr) override;

     virtual void SRAMWrite(u32 addr, u8 val) override;

 

+    virtual u8* GetSaveMemory() const override;

+    virtual u32 GetSaveMemoryLength() const override;

 protected:

     virtual void ProcessGPIO();

 

@@ -207,6 +212,19 @@ void ROMWrite(u32 addr, u16 val);
 u8 SRAMRead(u32 addr);

 void SRAMWrite(u32 addr, u8 val);

 

+/// This function is intended to allow frontends to save and load SRAM

+/// without using melonDS APIs.

+/// Modifying the emulated SRAM for any other reason is strongly discouraged.

+/// The returned pointer may be invalidated if the emulator is reset,

+/// or when a new game is loaded.

+/// Consequently, don't store the returned pointer for any longer than necessary.

+/// @returns Pointer to this cart's SRAM if a cart is loaded and supports SRAM, otherwise \c nullptr.

+u8* GetSaveMemory();

+

+/// @returns The length of the buffer returned by ::GetSaveMemory()

+/// if a cart is loaded and supports SRAM, otherwise zero.

+u32 GetSaveMemoryLength();

+

 }

 

 #endif // GBACART_H