X-Git-Url: https://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/5215a874429bf41ec24c83d6d5f631233faf3d76..4eabb8ad382f87aaee497d35e88c169da96b8fda:/common/lfdemod.c

diff --git a/common/lfdemod.c b/common/lfdemod.c
index ca126df3..7f8333ac 100644
--- a/common/lfdemod.c
+++ b/common/lfdemod.c
@@ -203,10 +203,10 @@ size_t findModStart(uint8_t dest[], size_t size, uint8_t threshold_value, uint8_
 //by marshmellow
 //takes 1s and 0s and searches for EM410x format - output EM ID
 // actually, no arguments needed - built this way in case we want this to be a direct call from "data " cmds in the future
-uint8_t Em410xDecode(uint8_t *BitStream, size_t *size, size_t *startIdx, uint32_t *hi, uint64_t *lo)
+int Em410xDecode(uint8_t *BitStream, size_t *size, size_t *startIdx, uint32_t *hi, uint64_t *lo)
 {
 	// sanity check
-	if (BitStream[1] > 1) return 0; 
+	if (BitStream[1] > 1) return -1; 
 	
 	uint8_t fmtlen;
 	*startIdx = 0;
@@ -215,8 +215,8 @@ uint8_t Em410xDecode(uint8_t *BitStream, size_t *size, size_t *startIdx, uint32_
 	// include 0 in front to help get start pos
 	uint8_t preamble[] = {0,1,1,1,1,1,1,1,1,1};
 	if (!preambleSearch(BitStream, preamble, sizeof(preamble), size, startIdx)) 
-		return 0;
-	if (*size < 64) return 0;
+		return -2;
+	if (*size < 64) return -3;
 	
 	fmtlen = (*size == 110) ? 22 : 10;
 
@@ -236,14 +236,14 @@ uint8_t Em410xDecode(uint8_t *BitStream, size_t *size, size_t *startIdx, uint32_
 		*lo = ((uint64_t)(bytebits_to_byte(BitStream + 24, 32)) << 32) | (bytebits_to_byte(BitStream + 24 + 32, 32));
 		break;
 	    } 
-	    default: return 0;
-	
+	    default: return -4;	
 	}
 	return 1;
 }
 
 //by marshmellow
 //demodulates strong heavily clipped samples
+//RETURN: num of errors.  if 0, is ok.
 int cleanAskRawDemod(uint8_t *BinStream, size_t *size, int clk, int invert, int high, int low)
 {
 	size_t bitCnt=0, smplCnt=0, errCnt=0;
@@ -387,25 +387,30 @@ int askdemod(uint8_t *BinStream, size_t *size, int *clk, int *invert, int maxErr
 //by marshmellow
 //take 10 and 01 and manchester decode
 //run through 2 times and take least errCnt
-int manrawdecode(uint8_t * BitStream, size_t *size, uint8_t invert){
+int manrawdecode(uint8_t *BitStream, size_t *size, uint8_t invert){
+
+	// sanity check
+	if (*size < 16) return -1;
+	
 	int errCnt = 0, bestErr = 1000;
 	uint16_t bitnum = 0, MaxBits = 512, bestRun = 0;
 	size_t i, k;
-	if (*size < 16) return -1;
+
 	//find correct start position [alignment]
-	for (k=0; k < 2; ++k){
-		for (i=k; i<*size-3; i += 2)
+	for (k = 0; k < 2; ++k){
+		for (i = k; i < *size-3; i += 2) {
 			if (BitStream[i] == BitStream[i+1])
 				errCnt++;
-
+		}
 		if (bestErr > errCnt){
 			bestErr = errCnt;
 			bestRun = k;
 		}
-		errCnt=0;
+		errCnt = 0;
 	}
+	
 	//decode
-	for (i=bestRun; i < *size-3; i += 2){
+	for (i = bestRun; i < *size-3; i += 2){
 		if (BitStream[i] == 1 && (BitStream[i+1] == 0)){
 			BitStream[bitnum++] = invert;
 		} else if ((BitStream[i] == 0) && BitStream[i+1] == 1){
@@ -413,9 +418,9 @@ int manrawdecode(uint8_t * BitStream, size_t *size, uint8_t invert){
 		} else {
 			BitStream[bitnum++] = 7;
 		}
-		if (bitnum>MaxBits) break;
+		if (bitnum > MaxBits) break;
 	}
-	*size=bitnum;
+	*size = bitnum;
 	return bestErr;
 }