Add emunand support for prototype NFIRM (by @Wack0)

arm9/source/emunand.c

@@ -111,6 +111,23 @@ void locateEmuNand(FirmwareSource *nandType, u32 *emunandIndex, bool configureCt
     else *nandType = FIRMWARE_SYSNAND;
 }
 
+static inline u32 getProtoSdmmc(u32 *sdmmc, u32 firmVersion)
+{
+    switch(firmVersion)
+    {
+        case 243: // SDK 0.9.x (0.9.7?)
+            *sdmmc = (0x080AAA28 + 0x4e0);
+            break;
+        case 238: // SDK 0.10
+            *sdmmc = (0x080BEA70 + 0x690);
+            break;
+        default:
+            return 1;
+    }
+
+    return 0;
+}
+
 static inline u32 getOldSdmmc(u32 *sdmmc, u32 firmVersion)
 {
     switch(firmVersion)
@@ -166,6 +183,111 @@ static inline u32 patchNandRw(u8 *pos, u32 size, u32 hookAddr)
     return 0;
 }
 
+static inline u32 patchProtoNandRw(u8 *pos, u32 size, u32 hookAddr, u32 hookCidAddr)
+{
+    //Look for read/write code
+    static const u8 pattern[] = {
+        0x03, 0x00, 0x51, 0xE3, // cmp r1, #3
+        0x02, 0xC0, 0xA0, 0xE1, // mov r12, r2
+        0x04, 0x00, 0x80, 0xE2, // add r0, r0, #4
+    };
+
+    u32 *writeOffset = (u32 *)memsearch(pos, pattern, size, sizeof(pattern));
+
+    if(writeOffset == NULL) return 1;
+
+    u32 *readOffset = (u32 *)memsearch((u8 *)(writeOffset + 3), pattern, 0x400, sizeof(pattern));
+
+    if(readOffset == NULL) return 1;
+
+    // Find the sdmmc mount/init(?) function
+    static const u8 mount_pattern[] = {
+        0x20, 0x00, 0x84, 0xE2, // add r0, r4, 0x20
+        0x01, 0x20, 0xA0, 0xE3, // mov r2, #1
+        0x00, 0x10, 0xA0, 0xE3, // mov r1, #0
+    };
+    u32* mountOffset = (u32*) memsearch(pos, mount_pattern, size, sizeof(mount_pattern));
+    if (mountOffset == NULL) return 1;
+
+    // Find the sdmmc read cid function.
+    static const u8 readcid_pattern[] = {
+        0x31, 0xFF, 0x2F, 0xE1, // blx r1
+        0x20, 0x60, 0x9F, 0xE5, // ldr r6, [pc, #0x20] // =failing_result
+        0x00, 0x00, 0x50, 0xE3, // cmp r0, #0
+    };
+    u32* readCidOffset = (u32*) memsearch(pos, readcid_pattern, size, sizeof(readcid_pattern));
+    if (readCidOffset == NULL) return 1;
+    readCidOffset -= 5;
+
+    mountOffset[1] = 0xe3a02000; // mov r2, #0 // sd-card
+
+    readOffset[0] = writeOffset[0] = 0xe52de004; // push {lr}
+    readOffset[1] = writeOffset[1] = 0xe59fc000; // ldr r12, [pc, #0]
+    readOffset[2] = writeOffset[2] = 0xe12fff3c; // blx r12
+    readOffset[3] = writeOffset[3] = hookAddr;
+
+    readCidOffset[0] = 0xe59fc000; // ldr r12, [pc, #0]
+    readCidOffset[1] = 0xe12fff3c; // blx r12
+    readCidOffset[2] = hookCidAddr;
+
+    // Read the emmc cid into the place hook will copy it from
+    sdmmc_get_cid(1, emunandPatchNandCid);
+
+    return 0;
+}
+
+static inline u32 patchProtoNandRw238(u8 *pos, u32 size, u32 hookAddr, u32 hookCidAddr)
+{
+    //Look for read/write code
+    static const u8 pattern[] = {
+        0x03, 0x00, 0x50, 0xE3, // cmp r0, #3
+        0x00, 0x00, 0xA0, 0x13, // movne r0, #0
+        0x01, 0x00, 0xA0, 0x03, // moveq r0, #1
+    };
+
+    u32 *writeOffset = (u32 *)memsearch(pos, pattern, size, sizeof(pattern));
+
+    if(writeOffset == NULL) return 1;
+
+    u32 *readOffset = (u32 *)memsearch((u8 *)(writeOffset + 3), pattern, 0x400, sizeof(pattern));
+
+    if(readOffset == NULL) return 1;
+
+    // Find the mmc static ctor...
+    static const u8 mount_pattern[] = {
+        0x08, // last byte of some ptr to something in P9
+        0x01, 0x01, 0x00, 0x00, // emmc controller id
+    };
+    u8* mountOffset = (u8*) memsearch(pos, mount_pattern, size, sizeof(mount_pattern));
+    if (mountOffset == NULL) return 1;
+    mountOffset++;
+
+    // Find the sdmmc read cid function.
+    static const u8 readcid_pattern[] = {
+        0x31, 0xFF, 0x2F, 0xE1, // blx r1
+        0x20, 0x60, 0x9F, 0xE5, // ldr r6, [pc, #0x20] // =failing_result
+        0x00, 0x00, 0x50, 0xE3, // cmp r0, #0
+    };
+    u32* readCidOffset = (u32*) memsearch(pos, readcid_pattern, size, sizeof(readcid_pattern));
+    if (readCidOffset == NULL) return 1;
+    readCidOffset -= 5;
+
+    *(u32*)mountOffset = 0x300; // sd card
+
+    readOffset[0] = writeOffset[0] = 0xe59fc000; // ldr r12, [pc, #0]
+    readOffset[1] = writeOffset[1] = 0xe12fff3c; // blx r12
+    readOffset[2] = writeOffset[2] = hookAddr;
+
+    readCidOffset[0] = 0xe59fc000; // ldr r12, [pc, #0]
+    readCidOffset[1] = 0xe12fff3c; // blx r12
+    readCidOffset[2] = hookCidAddr;
+
+    // Read the emmc cid into the place hook will copy it from
+    sdmmc_get_cid(1, emunandPatchNandCid);
+
+    return 0;
+}
+
 u32 patchEmuNand(u8 *process9Offset, u32 process9Size, u32 firmVersion)
 {
     u32 ret = 0;
@@ -184,3 +306,33 @@ u32 patchEmuNand(u8 *process9Offset, u32 process9Size, u32 firmVersion)
 
     return ret;
 }
+
+u32 patchProtoEmuNand(u8 *process9Offset, u32 process9Size)
+{
+    extern u32 firmProtoVersion;
+    u32 ret = 0;
+
+    // Add the data of the found EmuNAND
+    emunandPatchNandOffset = emuOffset;
+    emunandPatchNcsdHeaderOffset = emuHeader;
+
+    // Find and add the SDMMC struct
+    u32 sdmmc;
+    ret += getProtoSdmmc(&sdmmc, firmProtoVersion);
+    if(!ret) emunandPatchSdmmcStructPtr = sdmmc;
+
+    // Add EmuNAND hooks
+    switch (firmProtoVersion) {
+        case 243: // SDK 0.9.x (0.9.7?)
+            ret += patchProtoNandRw(process9Offset, process9Size, (u32)emunandProtoPatch, (u32)emunandProtoCidPatch);
+            break;
+        case 238: // SDK 0.10.x
+            ret += patchProtoNandRw238(process9Offset, process9Size, (u32)emunandProtoPatch238, (u32)emunandProtoCidPatch);
+            break;
+        default:
+            ret++;
+            break;
+    }
+
+    return ret;
+}

arm9/source/emunand.h

@@ -39,3 +39,4 @@ extern u32 emuOffset,
 
 void locateEmuNand(FirmwareSource *nandType, u32 *emunandIndex, bool configureCtrNandParams);
 u32 patchEmuNand(u8 *process9Offset, u32 process9Size, u32 firmVersion);
+u32 patchProtoEmuNand(u8 *process9Offset, u32 process9Size);

arm9/source/emunand_patch.s

@@ -45,19 +45,150 @@ emunandPatch:
 
 .pool
 
+_emunandPatchEnd:
+
+.global emunandProtoPatch
+emunandProtoPatch:
+    @ Save registers
+    push {r0-r3}
+
+    @ If we're already trying to access the SD, return
+    ldr r2, [r0, #4]
+    ldr r1, emunandPatchSdmmcStructPtr
+    cmp r2, r1
+    beq _out
+
+    ldrb r2, [r1, #0xc] @ Get sdmc->m_isInitialised
+    cmp r2, #0 @ Is initialised?
+    beq _pastSdmc @ if not, use "NAND" object, patched elsewhere to access SD
+    str r1, [r0, #4] @ Set object to be SD
+    _pastSdmc:
+    ldr r2, [r0, #8] @ Get sector to read
+    cmp r2, #0 @ For GW compatibility, see if we're trying to read the ncsd header (sector 0)
+
+    ldr r3, emunandPatchNandOffset
+    add r2, r3 @ Add the offset to the NAND in the SD
+
+    ldreq r3, emunandPatchNcsdHeaderOffset
+    addeq r2, r3 @ If we're reading the ncsd header, add the offset of that sector
+
+    str r2, [r0, #8] @ Store sector to read
+
+    _out:
+        @ Restore registers
+        pop {r0-r3}
+        @ Execute original code that got patched.
+        cmp r1, #3
+        mov r12, r2
+        add r0, r0, #4
+        movne r1, #0
+        moveq r1, #1
+        @ r2 about to be overwritten, so it's free to use here.
+        @ Save off our return address and restore lr.
+        mov r2, lr
+        pop {lr}
+        @ r2+0 is return address (patched movne r1, #0)
+        @ r2+4 is moveq r1, #1
+        @ r2+8 is the following instruction (mov r2, r3)
+        add r2, #8
+        bx r2
+
+.global emunandProtoCidPatch
+emunandProtoCidPatch:
+    @ If we're already trying to access the SD, return
+    ldr r4, emunandPatchSdmmcStructPtr
+    cmp r0, r4
+    beq _cid_return
+    
+    @ Trying to access nand, so copy the NAND cid into r1
+    adr r4, emunandPatchNandCid
+    ldr r2, [r4, #0]
+    ldr r3, [r4, #4]
+    ldr r5, [r4, #8]
+    ldr r6, [r4, #0xc]
+    str r2, [r1, #0]
+    str r3, [r1, #4]
+    str r5, [r1, #8]
+    str r6, [r1, #0xc]
+    @ And return from whence we came
+    mov r0, #0
+    pop {r4-r6, pc}
+    
+    _cid_return:
+        @ Execute original code that got patched.
+        mov r4, r0
+        ldr r0, [r0]
+        mov r5, r1
+        @ lr+0 is return address (patched mov r5, r1)
+        @ lr+4 is following instruction (ldr r1, [r0,#8])
+        add lr, #4
+        bx lr
+
+.global emunandProtoPatch238
+emunandProtoPatch238:
+    @ Save registers
+    push {r0-r3}
+
+    @ If we're already trying to access the SD, return
+    ldr r2, [r4, #4]
+    ldr r1, emunandPatchSdmmcStructPtr
+    cmp r2, r1
+    beq _out238
+
+    ldr r2, [r1, #0x24] @ Get sdmc->m_someObjInitedLater
+    cmp r2, #0 @ Is initialised?
+    beq _pastSdmc238 @ if not, use "NAND" object, patched elsewhere to access SD
+    str r1, [r4, #4] @ Set object to be SD
+    _pastSdmc238:
+
+    ldr r2, [r4, #8] @ Get sector to read
+    cmp r2, #0 @ For GW compatibility, see if we're trying to read the ncsd header (sector 0)
+
+    ldr r3, emunandPatchNandOffset
+    add r2, r3 @ Add the offset to the NAND in the SD
+
+    ldreq r3, emunandPatchNcsdHeaderOffset
+    addeq r2, r3 @ If we're reading the ncsd header, add the offset of that sector
+
+    str r2, [r4, #8] @ Store sector to read
+
+    _out238:
+        @ Restore registers
+        pop {r0-r3}
+        @ Execute original code that got patched.
+        cmp r0, #3
+        movne r0, #0
+        moveq r0, #1
+        @ r1 about to be overwritten, so it's free to use here.
+        @ Save off our return address.
+        mov r1, lr
+        @ r1+0 is return address (patched moveq r1, #1)
+        @ r1+4 is tst r0, #0xff or sub sp, sp, #0xc
+        add r1, #4
+        bx r1
+
+.pool
+
 .global emunandPatchSdmmcStructPtr
 .global emunandPatchNandOffset
 .global emunandPatchNcsdHeaderOffset
+.global emunandPatchNandCid
 
+_emunandPatchBssStart:
 emunandPatchSdmmcStructPtr:     .word   0 @ Pointer to sdmmc struct
 emunandPatchNandOffset:         .word   0 @ For rednand this should be 1
 emunandPatchNcsdHeaderOffset:   .word   0 @ Depends on nand manufacturer + emunand type (GW/RED)
+emunandPatchNandCid:                      @ Store emmc cid here, to override "sdmc's" when trying to read emmc's
+    .word 0,0,0,0 
+_emunandPatchBssEnd:
 
 .pool
 .balign 4
 
-_emunandPatchEnd:
-
 .global emunandPatchSize
 emunandPatchSize:
     .word _emunandPatchEnd - emunandPatch
+
+.global emunandPatchBssSize
+emunandPatchBssSize:
+    .word _emunandPatchBssEnd - _emunandPatchBssStart

arm9/source/firm.c

@@ -155,7 +155,21 @@ u32 loadNintendoFirm(FirmwareType *firmType, FirmwareSource nandType, bool loadF
     u32 firmVersion = 0xFFFFFFFF,
         firmSize;
 
-    bool ctrNandError = isSdMode && !remountCtrNandPartition(false);
+    bool ctrNandError = true;
+    bool loadedFromStorage = false;
+    bool storageLoadError = false;
+
+    // Try loading FIRM from sdmc first if specified.
+    if (loadFromStorage) {
+        firmSize = loadFirmFromStorage(*firmType);
+        if (firmSize != 0) loadedFromStorage = true;
+        else storageLoadError = true;
+    }
+
+    // Remount ctrnand and load FIRM from it if loading from sdmc failed.
+    if (!loadedFromStorage) {
+        ctrNandError = isSdMode && !remountCtrNandPartition(false);
+    }
 
     if(!ctrNandError)
     {
@@ -170,10 +184,8 @@ u32 loadNintendoFirm(FirmwareType *firmType, FirmwareSource nandType, bool loadF
             if(!firmSize || !checkFirm(firmSize)) ctrNandError = true;
         }
     }
-
+    // If CTRNAND load failed, and it wasn't tried yet, load FIRM from sdmc.
-    bool loadedFromStorage = false;
+    if (ctrNandError && !storageLoadError)
-
-    if(loadFromStorage || ctrNandError)
     {
         u32 result = loadFirmFromStorage(*firmType);
 
@@ -182,33 +194,25 @@ u32 loadNintendoFirm(FirmwareType *firmType, FirmwareSource nandType, bool loadF
             loadedFromStorage = true;
             firmSize = result;
         }
-        else if(ctrNandError) error("Unable to mount CTRNAND or load the CTRNAND FIRM.\nPlease use an external one.");
+        else storageLoadError = true;
     }
+    // If all attempts failed, panic.
+    if(ctrNandError && storageLoadError) error("Unable to mount CTRNAND or load the CTRNAND FIRM.\nPlease use an external one.");
 
     //Check that the FIRM is right for the console from the Arm9 section address
-    if((firm->section[3].offset != 0 ? firm->section[3].address : firm->section[2].address) != (ISN3DS ? (u8 *)0x8006000 : (u8 *)0x8006800))
+    bool isO3dsFirm = firm->section[3].offset == 0 && firm->section[2].address == (u8 *)0x8006800;
-        error("The %s FIRM is not for this console.", loadedFromStorage ? "external" : "CTRNAND");
-
-    if(!ISN3DS && *firmType == NATIVE_FIRM && firm->section[0].address == (u8 *)0x1FF80000)
-    {
-        //We can't boot < 3.x EmuNANDs
-        if(nandType != FIRMWARE_SYSNAND) error("An old unsupported EmuNAND has been detected.\nLuma3DS is unable to boot it.");
-
-        //If you want to use SAFE_FIRM on 1.0, use Luma from NAND & comment this line:
-        if(isSafeMode) error("SAFE_MODE is not supported on 1.x/2.x FIRM.");
-
-        *firmType = NATIVE_FIRM1X2X;
-    }
 
     if(loadedFromStorage || ISDEVUNIT)
     {
         firmVersion = 0xFFFFFFFF;
 
-        if(!ISN3DS && (*firmType == NATIVE_FIRM || *firmType == NATIVE_FIRM1X2X))
+        if(isO3dsFirm && (*firmType == NATIVE_FIRM || *firmType == NATIVE_FIRM1X2X))
         {
-            __attribute__((aligned(4))) static const u8 hashes[4][0x20] = {
+            __attribute__((aligned(4))) static const u8 hashes[5][0x20] = {
                 {0xD7, 0x43, 0x0F, 0x27, 0x8D, 0xC9, 0x3F, 0x4C, 0x96, 0xB5, 0xA8, 0x91, 0x48, 0xDB, 0x08, 0x8A,
                  0x7E, 0x46, 0xB3, 0x95, 0x65, 0xA2, 0x05, 0xF1, 0xF2, 0x41, 0x21, 0xF1, 0x0C, 0x59, 0x6A, 0x9D},
+                {0x93, 0xDF, 0x49, 0xA1, 0x24, 0x86, 0xBB, 0x6F, 0xAF, 0x49, 0x99, 0x2D, 0xD0, 0x8D, 0xB1, 0x88,
+                 0x8A, 0x00, 0xB6, 0xDD, 0x36, 0x89, 0xC0, 0xE2, 0xC9, 0xA9, 0x99, 0x62, 0x57, 0x5E, 0x6C, 0x23},
                 {0x39, 0x75, 0xB5, 0x28, 0x24, 0x5E, 0x8B, 0x56, 0xBC, 0x83, 0x79, 0x41, 0x09, 0x2C, 0x42, 0xE6,
                  0x26, 0xB6, 0x80, 0x59, 0xA5, 0x56, 0xF9, 0xF9, 0x6E, 0xF3, 0x63, 0x05, 0x58, 0xDF, 0x35, 0xEF},
                 {0x81, 0x9E, 0x71, 0x58, 0xE5, 0x44, 0x73, 0xF7, 0x48, 0x78, 0x7C, 0xEF, 0x5E, 0x30, 0xE2, 0x28,
@@ -228,14 +232,19 @@ u32 loadNintendoFirm(FirmwareType *firmType, FirmwareSource nandType, bool loadF
                     firmProtoVersion = 243;
                     *firmType = NATIVE_PROTOTYPE;
                     break;
-                // Release
                 case 1:
+                    firmVersion = 0x0;
+                    firmProtoVersion = 238;
+                    *firmType = NATIVE_PROTOTYPE;
+                    break;
+                // Release
+                case 2:
                     firmVersion = 0x18;
                     break;
-                case 2:
+                case 3:
                     firmVersion = 0x1D;
                     break;
-                case 3:
+                case 4:
                     firmVersion = 0x1F;
                     break;
                 default:
@@ -244,6 +253,20 @@ u32 loadNintendoFirm(FirmwareType *firmType, FirmwareSource nandType, bool loadF
         }
     }
 
+    if(*firmType != NATIVE_PROTOTYPE && (firm->section[3].offset != 0 ? firm->section[3].address : firm->section[2].address) != (ISN3DS ? (u8 *)0x8006000 : (u8 *)0x8006800))
+        error("The %s FIRM is not for this console.", loadedFromStorage ? "external" : "CTRNAND");
+
+    if(!ISN3DS && *firmType == NATIVE_FIRM && firm->section[0].address == (u8 *)0x1FF80000)
+    {
+        //We can't boot < 3.x EmuNANDs
+        if(nandType != FIRMWARE_SYSNAND) error("An old unsupported EmuNAND has been detected.\nLuma3DS is unable to boot it.");
+
+        //If you want to use SAFE_FIRM on 1.0, use Luma from NAND & comment this line:
+        if(isSafeMode) error("SAFE_MODE is not supported on 1.x/2.x FIRM.");
+
+        *firmType = NATIVE_FIRM1X2X;
+    }
+
     return firmVersion;
 }
 
@@ -747,7 +770,7 @@ u32 patch1x2xNativeAndSafeFirm(void)
     return ret;
 }
 
-u32 patchPrototypeNative(void)
+u32 patchPrototypeNative(FirmwareSource nandType)
 {
     u8 *arm9Section = (u8 *)firm + firm->section[2].offset;
 
@@ -758,13 +781,16 @@ u32 patchPrototypeNative(void)
 
     u32 kernel9Size = (u32)(process9Offset - arm9Section) - sizeof(Cxi) - 0x200,
         ret = 0;
-    
+
     ret += patchProtoNandSignatureCheck(process9Offset, process9Size);
 
     //Arm9 exception handlers
     ret += patchArm9ExceptionHandlersInstall(arm9Section, kernel9Size);
 
-    return ret; 
+    //Apply EmuNAND patches
+    if(nandType != FIRMWARE_SYSNAND) ret += patchProtoEmuNand(process9Offset, process9Size);
+
+    return ret;
 }
 
 void launchFirm(int argc, char **argv)

arm9/source/firm.h

@@ -35,5 +35,5 @@ u32 patchNativeFirm(u32 firmVersion, FirmwareSource nandType, bool loadFromStora
 u32 patchTwlFirm(u32 firmVersion, bool loadFromStorage, bool doUnitinfoPatch);
 u32 patchAgbFirm(bool loadFromStorage, bool doUnitinfoPatch);
 u32 patch1x2xNativeAndSafeFirm(void);
-u32 patchPrototypeNative(void);
+u32 patchPrototypeNative(FirmwareSource nandType);
 void launchFirm(int argc, char **argv);

arm9/source/large_patches.h

@@ -28,9 +28,11 @@
 
 #include "types.h"
 
-extern const u8 emunandPatch[];
+extern const u8 emunandPatch[], emunandProtoPatch[], emunandProtoCidPatch[];
-extern const u32 emunandPatchSize;
+extern const u8 emunandProtoPatch238[];
+extern const u32 emunandPatchSize, emunandPatchBssSize;
 extern u32 emunandPatchSdmmcStructPtr, emunandPatchNandOffset, emunandPatchNcsdHeaderOffset;
+extern u32 emunandPatchNandCid[4];
 
 extern const u8 rebootPatch[];
 extern const u32 rebootPatchSize;

arm9/source/main.c

@@ -387,7 +387,7 @@ boot:
             res = patch1x2xNativeAndSafeFirm();
             break;
         case NATIVE_PROTOTYPE:
-            res = patchPrototypeNative();
+            res = patchPrototypeNative(nandType);
             break;
     }
 

arm9/source/patches.c

@@ -56,7 +56,7 @@ u8 *getProcess9Info(u8 *pos, u32 size, u32 *process9Size, u32 *process9MemAddr)
     Cxi *off = (Cxi *)(temp - 0x100);
 
     *process9MemAddr = off->exHeader.systemControlInfo.textCodeSet.address;
-    
+
     // Prototype FW has a different NCCH format
     if (firmProtoVersion && firmProtoVersion <= 243)
     {
@@ -68,7 +68,7 @@ u8 *getProcess9Info(u8 *pos, u32 size, u32 *process9Size, u32 *process9MemAddr)
         *process9Size = (off->ncch.exeFsSize - 1) * 0x200;
         return (u8 *)off + (off->ncch.exeFsOffset + 1) * 0x200;
     }
-    
+
 }
 
 u32 *getKernel11Info(u8 *pos, u32 size, u32 *baseK11VA, u8 **freeK11Space, u32 **arm11SvcHandler, u32 **arm11ExceptionsPage)
@@ -853,12 +853,28 @@ u32 patchProtoNandSignatureCheck(u8 *pos, u32 size) {
         // Signature check function returns 0 if failed and 1 if succeeded.
         // Proc9 breaks if the returned value is 0, change it to break if
         // the returned value is 2 (never).
-        u8 *off = memsearch(pos, pattern, size, sizeof(pattern)) + 0x20;
+        u8 *off = memsearch(pos, pattern, size, sizeof(pattern));
         if (!off)
             return 1;
 
-        *off = 2;
+        off[0x20] = 2;
     }
 
+    else if (firmProtoVersion == 238) { // SDK 0.10
+        // Same patch as for v243 ported to the different ncsd_read() function
+        static const u8 pattern[] = {
+            0x00, 0x11, 0x9f, 0xe5,
+            0x00, 0x51, 0x9f, 0xe5,
+        };
+
+        u8 *off = memsearch(pos, pattern, size, sizeof(pattern));
+        if (!off)
+            return 1;
+
+        off[0x20] = 2;
+    }
+
+    else return 1;
+
     return 0;
 }