Fix viking demod bug - clean my indala demod code

NOTE lf indalademod is still available as it uses a different technique
to demodulating, which sometimes works better (and sometimes worse).

client/cmddata.c

@@ -649,7 +649,7 @@ int CmdVikingDemod(const char *Cmd)
 	//call lfdemod.c demod for gProxII
 	int ans = VikingDemod_AM(DemodBuffer, &size);
 	if (ans < 0) {
-		if (g_debugMode) PrintAndLog("Error Viking_Demod");
+		if (g_debugMode) PrintAndLog("Error Viking_Demod %d", ans);
 		return 0;
 	}
 	//got a good demod
@@ -1615,61 +1615,33 @@ int CmdIndalaDecode(const char *Cmd)
 		return 0;
 	}
 	uint8_t invert=0;
-	ans = indala26decode(DemodBuffer, &DemodBufferLen, &invert);
+	size_t size = DemodBufferLen;
-	if (ans < 1) {
+	size_t startIdx = indala26decode(DemodBuffer, &size, &invert);
+	if (startIdx < 1) {
 		if (g_debugMode==1)
 			PrintAndLog("Error2: %d",ans);
 		return -1;
 	}
-	char showbits[251]={0x00};
+	setDemodBuf(DemodBuffer, size, startIdx);
 	if (invert)
 		if (g_debugMode==1)
 			PrintAndLog("Had to invert bits");
 
+	PrintAndLog("BitLen: %d",DemodBufferLen);
 	//convert UID to HEX
 	uint32_t uid1, uid2, uid3, uid4, uid5, uid6, uid7;
-	int idx;
+	uid1=bytebits_to_byte(DemodBuffer,32);
-	uid1=0;
+	uid2=bytebits_to_byte(DemodBuffer+32,32);
-	uid2=0;
+	if (DemodBufferLen==64) {
-	PrintAndLog("BitLen: %d",DemodBufferLen);
+		PrintAndLog("Indala UID=%s (%x%08x)", sprint_bin(DemodBuffer,DemodBufferLen), uid1, uid2);
-	if (DemodBufferLen==64){
+	} else {
-		for( idx=0; idx<64; idx++) {
+		uid3=bytebits_to_byte(DemodBuffer+64,32);
-			uid1=(uid1<<1)|(uid2>>31);
+		uid4=bytebits_to_byte(DemodBuffer+96,32);
-			if (DemodBuffer[idx] == 0) {
+		uid5=bytebits_to_byte(DemodBuffer+128,32);
-				uid2=(uid2<<1)|0;
+		uid6=bytebits_to_byte(DemodBuffer+160,32);
-				showbits[idx]='0';
+		uid7=bytebits_to_byte(DemodBuffer+192,32);
-			} else {
+		PrintAndLog("Indala UID=%s (%x%08x%08x%08x%08x%08x%08x)", 
-				uid2=(uid2<<1)|1;
+		    sprint_bin(DemodBuffer,DemodBufferLen), uid1, uid2, uid3, uid4, uid5, uid6, uid7);
-				showbits[idx]='1';
-			}
-		}
-		showbits[idx]='\0';
-		PrintAndLog("Indala UID=%s (%x%08x)", showbits, uid1, uid2);
-	}
-	else {
-		uid3=0;
-		uid4=0;
-		uid5=0;
-		uid6=0;
-		uid7=0;
-		for( idx=0; idx<DemodBufferLen; idx++) {
-			uid1=(uid1<<1)|(uid2>>31);
-			uid2=(uid2<<1)|(uid3>>31);
-			uid3=(uid3<<1)|(uid4>>31);
-			uid4=(uid4<<1)|(uid5>>31);
-			uid5=(uid5<<1)|(uid6>>31);
-			uid6=(uid6<<1)|(uid7>>31);
-			if (DemodBuffer[idx] == 0) {
-				uid7=(uid7<<1)|0;
-				showbits[idx]='0';
-			}
-			else {
-				uid7=(uid7<<1)|1;
-				showbits[idx]='1';
-			}
-		}
-		showbits[idx]='\0';
-		PrintAndLog("Indala UID=%s (%x%08x%08x%08x%08x%08x%08x)", showbits, uid1, uid2, uid3, uid4, uid5, uid6, uid7);
 	}
 	if (g_debugMode){
 		PrintAndLog("DEBUG: printing demodbuffer:");

common/lfdemod.c

@@ -602,7 +602,6 @@ int IOdemodFSK(uint8_t *dest, size_t size)
 // by marshmellow
 // find viking preamble 0xF200 in already demoded data
 int VikingDemod_AM(uint8_t *dest, size_t *size) {
-	if (justNoise(dest, *size)) return -1;
 	//make sure buffer has data
 	if (*size < 64*2) return -2;
 
@@ -614,7 +613,7 @@ int VikingDemod_AM(uint8_t *dest, size_t *size) {
 	    ^ bytebits_to_byte(dest+startIdx+24,8) ^ bytebits_to_byte(dest+startIdx+32,8) ^ bytebits_to_byte(dest+startIdx+40,8) 
 	    ^ bytebits_to_byte(dest+startIdx+48,8) ^ bytebits_to_byte(dest+startIdx+56,8);
 	if ( checkCalc != 0xA8 ) return -5;
-	if (*size != 64) return -5;
+	if (*size != 64) return -6;
 	//return start position
 	return (int) startIdx;
 }
@@ -1074,63 +1073,20 @@ void psk2TOpsk1(uint8_t *BitStream, size_t size)
 int indala26decode(uint8_t *bitStream, size_t *size, uint8_t *invert)
 {
 	//26 bit 40134 format  (don't know other formats)
-	int i;
+	uint8_t preamble[] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1};
-	int long_wait=29;//29 leading zeros in format
+	uint8_t preamble_i[] = {1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,0};
-	int start;
+	size_t startidx = 0; 
-	int first = 0;
+	if (!preambleSearch(bitStream, preamble, sizeof(preamble), size, &startidx)){
-	int first2 = 0;
+		// if didn't find preamble try again inverting
-	int bitCnt = 0;
+		if (!preambleSearch(bitStream, preamble_i, sizeof(preamble_i), size, &startidx)) return -1;
-	int ii;
+		*invert ^= 1;
-	// Finding the start of a UID
+	} 
-	for (start = 0; start <= *size - 250; start++) {
+	if (*size != 64 && *size != 224) return -2;
-		first = bitStream[start];
+	if (*invert==1)
-		for (i = start; i < start + long_wait; i++) {
+		for (size_t i = startidx; i < *size; i++)
-			if (bitStream[i] != first) {
+			bitStream[i] ^= 1;
-				break;
-			}
-		}
-		if (i == (start + long_wait)) {
-			break;
-		}
-	}
-	if (start == *size - 250 + 1) {
-		// did not find start sequence
-		return -1;
-	}
-	// Inverting signal if needed
-	if (first == 1) {
-		for (i = start; i < *size; i++) {
-			bitStream[i] = !bitStream[i];
-		}
-		*invert = 1;
-	}else *invert=0;
 
-	int iii;
+	return (int) startidx;
-	//found start once now test length by finding next one
-	for (ii=start+29; ii <= *size - 250; ii++) {
-		first2 = bitStream[ii];
-		for (iii = ii; iii < ii + long_wait; iii++) {
-			if (bitStream[iii] != first2) {
-				break;
-			}
-		}
-		if (iii == (ii + long_wait)) {
-			break;
-		}
-	}
-	if (ii== *size - 250 + 1){
-		// did not find second start sequence
-		return -2;
-	}
-	bitCnt=ii-start;
-
-	// Dumping UID
-	i = start;
-	for (ii = 0; ii < bitCnt; ii++) {
-		bitStream[ii] = bitStream[i++];
-	}
-	*size=bitCnt;
-	return 1;
 }
 
 // by marshmellow - demodulate NRZ wave (both similar enough)