added new functions

1 files changed, 130 insertions, 1 deletions

diff --git a/kmer_utils.c b/kmer_utils.c
index a1ff9b2..111e550 100644
--- a/kmer_utils.c
+++ b/kmer_utils.c
@@ -1,5 +1,27 @@
+// Copyright 2013 Calvin Morrison
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
 #include "kmer_total_count.h"
 
+const unsigned char alpha[256] = 
+{5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
+5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
+5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 0, 5, 1, 5, 5, 5, 2, 5, 5, 5, 5, 5, 5,
+5, 5, 5, 5, 5, 5, 3, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 0, 5, 1, 5, 5, 5, 2,
+5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 3, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
+5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
+5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
+5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
+5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
+5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5};
+
+inline unsigned long long pow_four(unsigned long long x) {
+	return (unsigned long long)1 << (x * 2);
+}
+
 // convert a string of k-mer size base-4 values  into a
 // base-10 index
 inline unsigned long num_to_index(const char *str, const int kmer, const long error_pos) {
@@ -46,10 +68,117 @@ void convert_kmer_to_num(char *str, const unsigned long length) {
       default:
         // Error Checking: use 4 so we can shift right twice
         // to check quickly is there is an non ACGT character 
-        str[i] = 4;
+        str[i] = 5;
     }
 
   }
 
 }
 
+char *strnstrip(const char *s, char *dest, int c, unsigned long long len) {
+
+	unsigned long long i = 0;
+	unsigned long long j = 0;
+
+	for(i = 0; i < len; i++) {
+		if(s[i] != c) {
+			dest[j] = s[i];
+			j++;
+		}
+	}
+
+	dest[j] = '\0';
+
+	return dest;
+}
+
+unsigned long long * get_kmer_counts_from_file(const char *fn, const unsigned int kmer) {
+	
+  char *line = NULL;
+  size_t len = 0;
+  ssize_t read;
+
+  long long i = 0;
+	long long posistion = 0;
+
+  FILE * const fh = fopen(fn, "r");
+  if(fh == NULL) {
+    fprintf(stderr, "Error opening %s - %s\n", fn, strerror(errno));
+    exit(EXIT_FAILURE);
+  }
+
+	// width is 4^kmer  
+	// there's a sneaky bitshift to avoid pow dependency
+	const unsigned long width = pow_four(kmer); 
+
+	// malloc our return array
+  unsigned long long * counts = malloc((width+ 1) * sizeof(unsigned long long));
+  if(counts == NULL)  {
+		fprintf(stderr, strerror(errno));
+    exit(EXIT_FAILURE);
+	}
+
+	char *str = malloc(4096);
+	if(str == NULL) { 
+		fprintf(stderr, strerror(errno));
+		exit(EXIT_FAILURE);
+	}
+
+	unsigned long long str_size = 4096;
+
+	while ((read = getdelim(&line, &len, '>', fh)) != -1) {
+
+		// find our first \n, this should be the end of the header
+		char *start = strchr(line, '\n');	
+		if(start == NULL) 
+			continue;
+
+		size_t start_len = strlen(start);
+
+
+		// if our current str buffer isn't big enough, realloc
+		if(start_len + 1 > str_size + 1) { 
+			str = realloc(str, start_len + 1);
+			if(str == NULL) { 
+				exit(EXIT_FAILURE);
+				fprintf(stderr, strerror(errno));
+			}
+		}
+
+		// strip out all other newlines to handle multiline sequences
+		str = strnstrip(start, str, '\n',start_len);
+		size_t seq_length = strlen(str);
+
+		// relace A, C, G and T with 0, 1, 2, 3 respectively
+		// everything else is 5 
+		for(i = 0; i < seq_length; i++) {
+			str[i] = alpha[(int)str[i]];
+		}
+
+		// loop through our string to process each k-mer
+		for(posistion = 0; posistion < (seq_length - kmer + 1); posistion++) {
+			unsigned long mer = 0;
+			unsigned long multiply = 1;
+
+			// for each char in the k-mer check if it is an error char
+			for(i = posistion + kmer - 1; i >= posistion; i--){
+				if(str[i] >> 2) { 
+					mer = width;
+					posistion = i;
+					goto next;
+				}
+
+				// multiply this char in the mer by the multiply
+				// and bitshift the multiply for the next round
+				mer += str[i] * multiply;
+				multiply = multiply << 2;
+			}
+			// use this point to get mer of our loop
+			next:
+			// bump up the mer value in the counts array
+			counts[mer]++;
+		}
+	} 
+
+	return counts;
+}