Merge pull request #127 from libretro/master

[libretro] merge cheat support changes

libretro/libretro.c

@@ -1190,114 +1190,57 @@ static uint32_t decode_cheat(char *string, int index)
    uint32_t address = 0;
    uint16_t data = 0;
    uint8_t ref = 0;
-   /* 16-bit Game Genie code (ABCD-EFGH) */
+
-   if ((strlen(string) >= 9) && (string[4] == '-'))
+   if ((system_hw & SYSTEM_PBC) == SYSTEM_MD){
-   {
+      //If system is Genesis-based
-      /* 16-bit system only */
+
-      if ((system_hw & SYSTEM_PBC) != SYSTEM_MD)
+      //Game-Genie
+      if ((strlen(string) >= 9) && (string[4] == '-'))
       {
-         return 0;
+         for (i = 0; i < 8; i++)
-      }
-      for (i = 0; i < 8; i++)
-      {
-         if (i == 4) string++;
-         p = strchr (ggvalidchars, *string++);
-         if (p == NULL) return 0;
-         n = p - ggvalidchars;
-         switch (i)
          {
-            case 0:
+            if (i == 4) string++;
-               data |= n << 3;
+            p = strchr (ggvalidchars, *string++);
-               break;
+            if (p == NULL) return 0;
-            case 1:
+            n = p - ggvalidchars;
-               data |= n >> 2;
+            switch (i)
-               address |= (n & 3) << 14;
+            {
-               break;
+               case 0:
-            case 2:
+                  data |= n << 3;
-               address |= n << 9;
+                  break;
-               break;
+               case 1:
-            case 3:
+                  data |= n >> 2;
-               address |= (n & 0xF) << 20 | (n >> 4) << 8;
+                  address |= (n & 3) << 14;
-               break;
+                  break;
-            case 4:
+               case 2:
-               data |= (n & 1) << 12;
+                  address |= n << 9;
-               address |= (n >> 1) << 16;
+                  break;
-               break;
+               case 3:
-            case 5:
+                  address |= (n & 0xF) << 20 | (n >> 4) << 8;
-               data |= (n & 1) << 15 | (n >> 1) << 8;
+                  break;
-               break;
+               case 4:
-            case 6:
+                  data |= (n & 1) << 12;
-               data |= (n >> 3) << 13;
+                  address |= (n >> 1) << 16;
-               address |= (n & 7) << 5;
+                  break;
-               break;
+               case 5:
-            case 7:
+                  data |= (n & 1) << 15 | (n >> 1) << 8;
-               address |= n;
+                  break;
-               break;
+               case 6:
+                  data |= (n >> 3) << 13;
+                  address |= (n & 7) << 5;
+                  break;
+               case 7:
+                  address |= n;
+                  break;
+            }
          }
+         /* code length */
+         len = 9;
       }
-      /* code length */
+
-      len = 9;
+      //Patch and PAR
-   }
+      else if ((strlen(string) >=9) && (string[6] == ':'))
-   /* 8-bit Game Genie code (DDA-AAA-XXX) */
-   else if ((strlen(string) >= 11) && (string[3] == '-') && (string[7] == '-'))
-   {
-      /* 8-bit system only */
-      if ((system_hw & SYSTEM_PBC) == SYSTEM_MD)
       {
-         return 0;
-      }
-      /* decode 8-bit data */
-      for (i=0; i<2; i++)
-      {
-         p = strchr (arvalidchars, *string++);
-         if (p == NULL) return 0;
-         n = (p - arvalidchars) & 0xF;
-         data |= (n << ((1 - i) * 4));
-      }
-      /* decode 16-bit address (low 12-bits) */
-      for (i=0; i<3; i++)
-      {
-         if (i==1) string++; /* skip separator */
-         p = strchr (arvalidchars, *string++);
-         if (p == NULL) return 0;
-         n = (p - arvalidchars) & 0xF;
-         address |= (n << ((2 - i) * 4));
-      }
-      /* decode 16-bit address (high 4-bits) */
-      p = strchr (arvalidchars, *string++);
-      if (p == NULL) return 0;
-      n = (p - arvalidchars) & 0xF;
-      n ^= 0xF; /* bits inversion */
-      address |= (n << 12);
-      /* RAM address are also supported */
-      if (address >= 0xC000)
-      {
-         /* convert to 24-bit Work RAM address */
-         address = 0xFF0000 | (address & 0x1FFF);
-      }
-      /* decode reference 8-bit data */
-      for (i=0; i<2; i++)
-      {
-         string++; /* skip separator and 2nd digit */
-         p = strchr (arvalidchars, *string++);
-         if (p == NULL) return 0;
-         n = (p - arvalidchars) & 0xF;
-         ref |= (n << ((1 - i) * 4));
-      }
-      ref = (ref >> 2) | ((ref & 0x03) << 6); /* 2-bit right rotation */
-      ref ^= 0xBA; /* XOR */
-      /* update old data value */
-      cheatlist[index].old = ref;
-      /* code length */
-      len = 11;
-   }
-   /* Action Replay code */
-   else if (string[6] == ':')
-   {
-      if ((system_hw & SYSTEM_PBC) == SYSTEM_MD)
-      {
-         /* 16-bit code (AAAAAA:DDDD) */
-         if (strlen(string) < 11) return 0;
          /* decode 24-bit address */
          for (i=0; i<6; i++)
          {
@@ -1311,19 +1254,125 @@ static uint32_t decode_cheat(char *string, int index)
          for (i=0; i<4; i++)
          {
             p = strchr (arvalidchars, *string++);
-            if (p == NULL) return 0;
+            if (p == NULL) break;
             n = (p - arvalidchars) & 0xF;
             data |= (n << ((3 - i) * 4));
          }
          /* code length */
          len = 11;
       }
-      else
+   } else {
+      //If System is Master-based
+
+      //Game Genie
+      if ((strlen(string) >=7) && (string[3] == '-'))
       {
-         /* 8-bit code (xxAAAA:DD) */
+         /* decode 8-bit data */
-         if (strlen(string) < 9) return 0;
+         for (i=0; i<2; i++)
-         /* decode 16-bit address */
+         {
+            p = strchr (arvalidchars, *string++);
+            if (p == NULL) return 0;
+            n = (p - arvalidchars) & 0xF;
+            data |= (n << ((1 - i) * 4));
+         }
+         /* decode 16-bit address (low 12-bits) */
+         for (i=0; i<3; i++)
+         {
+            if (i==1) string++; /* skip separator */
+            p = strchr (arvalidchars, *string++);
+            if (p == NULL) return 0;
+            n = (p - arvalidchars) & 0xF;
+            address |= (n << ((2 - i) * 4));
+         }
+         /* decode 16-bit address (high 4-bits) */
+         p = strchr (arvalidchars, *string++);
+         if (p == NULL) return 0;
+         n = (p - arvalidchars) & 0xF;
+         n ^= 0xF; /* bits inversion */
+         address |= (n << 12);
+         /* Optional: decode reference 8-bit data */
+         if (*string=='-')
+         {
+            for (i=0; i<2; i++)
+            {
+               string++; /* skip separator and 2nd digit */
+               p = strchr (arvalidchars, *string++);
+               if (p == NULL) return 0;
+               n = (p - arvalidchars) & 0xF;
+               ref |= (n << ((1 - i) * 4));
+            }
+            ref = (ref >> 2) | ((ref & 0x03) << 6); /* 2-bit right rotation */
+            ref ^= 0xBA; /* XOR */
+            /* code length */
+            len = 11;
+         }
+         else
+         {
+            /* code length */
+            len = 7;
+         }
+      }
+
+      //Action Replay
+      else if ((strlen(string) >=9) && (string[4] == '-')){
          string+=2;
+         /* decode 16-bit address */
+         for (i=0; i<4; i++)
+         {
+            p = strchr (arvalidchars, *string++);
+            if (p == NULL) return 0;
+            n = (p - arvalidchars) & 0xF;
+            address |= (n << ((3 - i) * 4));
+            if (i==1) string++;
+         }
+         /* decode 8-bit data */
+         for (i=0; i<2; i++)
+         {
+            p = strchr (arvalidchars, *string++);
+            if (p == NULL) return 0;
+            n = (p - arvalidchars) & 0xF;
+            data |= (n << ((1 - i) * 4));
+         }
+         /* code length */
+         len = 9;
+      }
+
+      //Fusion RAM
+      else if ((strlen(string) >=7) && (string[4] == ':'))
+      {
+         /* decode 16-bit address */
+         for (i=0; i<4; i++)
+         {
+            p = strchr (arvalidchars, *string++);
+            if (p == NULL) return 0;
+            n = (p - arvalidchars) & 0xF;
+            address |= (n << ((3 - i) * 4));
+         }
+         /* decode 8-bit data */
+         string++;
+         for (i=0; i<2; i++)
+         {
+            p = strchr (arvalidchars, *string++);
+            if (p == NULL) return 0;
+            n = (p - arvalidchars) & 0xF;
+            data |= (n << ((1 - i) * 4));
+         }
+         /* code length */
+         len = 7;
+      }
+
+      //Fusion ROM
+      else if ((strlen(string) >=9) && (string[6] == ':'))
+      {
+         /* decode reference 8-bit data */
+         for (i=0; i<2; i++)
+         {
+            p = strchr (arvalidchars, *string++);
+            if (p == NULL) return 0;
+            n = (p - arvalidchars) & 0xF;
+            ref |= (n << ((1 - i) * 4));
+         }
+         /* decode 16-bit address */
          for (i=0; i<4; i++)
          {
             p = strchr (arvalidchars, *string++);
@@ -1331,10 +1380,6 @@ static uint32_t decode_cheat(char *string, int index)
             n = (p - arvalidchars) & 0xF;
             address |= (n << ((3 - i) * 4));
          }
-         /* ROM addresses are not supported */
-         if (address < 0xC000) return 0;
-         /* convert to 24-bit Work RAM address */
-         address = 0xFF0000 | (address & 0x1FFF);
          /* decode 8-bit data */
          string++;
          for (i=0; i<2; i++)
@@ -1347,6 +1392,11 @@ static uint32_t decode_cheat(char *string, int index)
          /* code length */
          len = 9;
       }
+      /* convert to 24-bit Work RAM address */
+      if (address >= 0xC000)
+      {
+         address = 0xFF0000 | (address & 0x1FFF);
+      }
    }
    /* Valid code found ? */
    if (len)
@@ -1354,6 +1404,7 @@ static uint32_t decode_cheat(char *string, int index)
       /* update cheat address & data values */
       cheatlist[index].address = address;
       cheatlist[index].data = data;
+      cheatlist[index].old = ref;
    }
    /* return code length (0 = invalid) */
    return len;
@@ -1497,8 +1548,8 @@ void ROMCheatUpdate(void)
     /* get current banked ROM address */
     ptr = &z80_readmap[(cheatlist[index].address) >> 10][cheatlist[index].address & 0x03FF];
 
-    /* check if reference matches original ROM data */
+    /* check if reference exists and matches original ROM data */
-    if (((uint8_t)cheatlist[index].old) == *ptr)
+    if (!cheatlist[index].old || ((uint8_t)cheatlist[index].old) == *ptr)
     {
       /* patch data */
       *ptr = cheatlist[index].data;
@@ -1892,32 +1943,46 @@ void retro_cheat_reset(void)
 
 void retro_cheat_set(unsigned index, bool enabled, const char *code)
 {
+	char codeCopy[256];
+	char *buff;
+   
+   /* Avoid crashing when giving empty input */
+   if (code=='\0') return;
+
    /* clear existing ROM patches */
    clear_cheats();
 
-   /* interpret code and check if this is a valid cheat code */
+   /* Detect and split multiline cheats */
-   if (decode_cheat((char *)code, maxcheats))
+	strcpy(codeCopy,code);
-   {
+   buff = strtok(codeCopy,"+");
-      int i;
 
-      /* check if cheat code already exists */
+	while (buff != NULL)
-      for (i=0; i<maxcheats; i++)
+	{
+      /* interpret code and check if this is a valid cheat code */
+      if (decode_cheat((char *)buff, maxcheats))
       {
-         if ((cheatlist[i].address == cheatlist[maxcheats].address)
+         int i;
-                && (cheatlist[i].data == cheatlist[maxcheats].data))
-            break;
-      }
 
-      /* cheat can be enabled or disabled */
+         /* check if cheat code already exists */
-      cheatlist[i].enable = enabled;
+         for (i=0; i<maxcheats; i++)
+         {
+            if ((cheatlist[i].address == cheatlist[maxcheats].address)
+                   && (cheatlist[i].data == cheatlist[maxcheats].data))
+               break;
+         }
 
-      /* if new cheat code, check current cheat count */
+         /* cheat can be enabled or disabled */
-      if ((i == maxcheats) && (i < MAX_CHEATS))
+         cheatlist[i].enable = enabled;
-      {
+
-         /* increment cheat count */
+         /* if new cheat code, check current cheat count */
-         maxcheats++;
+         if ((i == maxcheats) && (i < MAX_CHEATS))
+         {
+            /* increment cheat count */
+            maxcheats++;
+         }
       }
-   }
+      buff = strtok(NULL,"+");
+	}
 
    /* apply ROM patches */
    apply_cheats();