r819: mappy to support cs/MD

format.c

@@ -133,10 +133,10 @@ void mm_write_sam_hdr(const mm_idx_t *idx, const char *rg, const char *ver, int
 	free(str.s);
 }
 
-static void write_cs_core(kstring_t *s, const uint8_t *tseq, const uint8_t *qseq, const mm_reg1_t *r, char *tmp, int no_iden)
+static void write_cs_core(kstring_t *s, const uint8_t *tseq, const uint8_t *qseq, const mm_reg1_t *r, char *tmp, int no_iden, int write_tag)
 {
 	int i, q_off, t_off;
-	mm_sprintf_lite(s, "\tcs:Z:");
+	if (write_tag) mm_sprintf_lite(s, "\tcs:Z:");
 	for (i = q_off = t_off = 0; i < (int)r->p->n_cigar; ++i) {
 		int j, op = r->p->cigar[i]&0xf, len = r->p->cigar[i]>>4;
 		assert(op >= 0 && op <= 3);
@@ -181,10 +181,10 @@ static void write_cs_core(kstring_t *s, const uint8_t *tseq, const uint8_t *qseq
 	assert(t_off == r->re - r->rs && q_off == r->qe - r->qs);
 }
 
-static void write_MD_core(kstring_t *s, const uint8_t *tseq, const uint8_t *qseq, const mm_reg1_t *r, char *tmp)
+static void write_MD_core(kstring_t *s, const uint8_t *tseq, const uint8_t *qseq, const mm_reg1_t *r, char *tmp, int write_tag)
 {
 	int i, q_off, t_off, l_MD = 0;
-	mm_sprintf_lite(s, "\tMD:Z:");
+	if (write_tag) mm_sprintf_lite(s, "\tMD:Z:");
 	for (i = q_off = t_off = 0; i < (int)r->p->n_cigar; ++i) {
 		int j, op = r->p->cigar[i]&0xf, len = r->p->cigar[i]>>4;
 		assert(op >= 0 && op <= 2); // introns (aka reference skips) are not supported
@@ -210,7 +210,7 @@ static void write_MD_core(kstring_t *s, const uint8_t *tseq, const uint8_t *qseq
 	assert(t_off == r->re - r->rs && q_off == r->qe - r->qs);
 }
 
-static void write_cs_or_MD(void *km, kstring_t *s, const mm_idx_t *mi, const mm_bseq1_t *t, const mm_reg1_t *r, int no_iden, int is_MD)
+static void write_cs_or_MD(void *km, kstring_t *s, const mm_idx_t *mi, const mm_bseq1_t *t, const mm_reg1_t *r, int no_iden, int is_MD, int write_tag)
 {
 	extern unsigned char seq_nt4_table[256];
 	int i;
@@ -230,11 +230,34 @@ static void write_cs_or_MD(void *km, kstring_t *s, const mm_idx_t *mi, const mm_
 			qseq[r->qe - i - 1] = c >= 4? 4 : 3 - c;
 		}
 	}
-	if (is_MD) write_MD_core(s, tseq, qseq, r, tmp);
+	if (is_MD) write_MD_core(s, tseq, qseq, r, tmp, write_tag);
-	else write_cs_core(s, tseq, qseq, r, tmp, no_iden);
+	else write_cs_core(s, tseq, qseq, r, tmp, no_iden, write_tag);
 	kfree(km, qseq); kfree(km, tseq); kfree(km, tmp);
 }
 
+int mm_gen_cs_or_MD(void *km, char **buf, int *max_len, const mm_idx_t *mi, const mm_reg1_t *r, const char *seq, int is_MD, int no_iden)
+{
+	mm_bseq1_t t;
+	kstring_t str;
+	str.s = *buf, str.l = 0, str.m = *max_len;
+	t.l_seq = strlen(seq);
+	t.seq = (char*)seq;
+	write_cs_or_MD(km, &str, mi, &t, r, no_iden, is_MD, 0);
+	*max_len = str.m;
+	*buf = str.s;
+	return str.l;
+}
+
+int mm_gen_cs(void *km, char **buf, int *max_len, const mm_idx_t *mi, const mm_reg1_t *r, const char *seq, int no_iden)
+{
+	return mm_gen_cs_or_MD(km, buf, max_len, mi, r, seq, 0, no_iden);
+}
+
+int mm_gen_MD(void *km, char **buf, int *max_len, const mm_idx_t *mi, const mm_reg1_t *r, const char *seq)
+{
+	return mm_gen_cs_or_MD(km, buf, max_len, mi, r, seq, 1, 0);
+}
+
 static inline void write_tags(kstring_t *s, const mm_reg1_t *r)
 {
 	int type;
@@ -277,7 +300,7 @@ void mm_write_paf(kstring_t *s, const mm_idx_t *mi, const mm_bseq1_t *t, const m
 			mm_sprintf_lite(s, "%d%c", r->p->cigar[k]>>4, "MIDNSHP=XB"[r->p->cigar[k]&0xf]);
 	}
 	if (r->p && (opt_flag & (MM_F_OUT_CS|MM_F_OUT_MD)))
-		write_cs_or_MD(km, s, mi, t, r, !(opt_flag&MM_F_OUT_CS_LONG), opt_flag&MM_F_OUT_MD);
+		write_cs_or_MD(km, s, mi, t, r, !(opt_flag&MM_F_OUT_CS_LONG), opt_flag&MM_F_OUT_MD, 1);
 	if ((opt_flag & MM_F_COPY_COMMENT) && t->comment)
 		mm_sprintf_lite(s, "\t%s", t->comment);
 }
@@ -476,7 +499,7 @@ void mm_write_sam2(kstring_t *s, const mm_idx_t *mi, const mm_bseq1_t *t, int se
 			}
 		}
 		if (r->p && (opt_flag & (MM_F_OUT_CS|MM_F_OUT_MD)))
-			write_cs_or_MD(km, s, mi, t, r, !(opt_flag&MM_F_OUT_CS_LONG), opt_flag&MM_F_OUT_MD);
+			write_cs_or_MD(km, s, mi, t, r, !(opt_flag&MM_F_OUT_CS_LONG), opt_flag&MM_F_OUT_MD, 1);
 		if (cigar_in_tag)
 			write_sam_cigar(s, flag, 1, t->l_seq, r, opt_flag);
 	}

main.c

@@ -10,7 +10,7 @@
 #include "getopt.h"
 #endif
 
-#define MM_VERSION "2.11-r815-dirty"
+#define MM_VERSION "2.11-r819-dirty"
 
 #ifdef __linux__
 #include <sys/resource.h>

map.c

@@ -29,6 +29,11 @@ void mm_tbuf_destroy(mm_tbuf_t *b)
 	free(b);
 }
 
+void *mm_tbuf_get_km(mm_tbuf_t *b)
+{
+	return b->km;
+}
+
 static int mm_dust_minier(void *km, int n, mm128_t *a, int l_seq, const char *seq, int sdust_thres)
 {
 	int n_dreg, j, k, u = 0;
@@ -682,7 +687,7 @@ int mm_split_merge(int n_segs, const char **fn, const mm_mapopt_t *opt, int n_sp
 	for (pl.rid_shift[0] = 0, i = 1; i < n_split_idx; ++i)
 		pl.rid_shift[i] += pl.rid_shift[i - 1];
 	if (opt->flag & MM_F_OUT_SAM)
-		for (i = 0; i < pl.mi->n_seq; ++i)
+		for (i = 0; i < (int32_t)pl.mi->n_seq; ++i)
 			printf("@SQ\tSN:%s\tLN:%d\n", pl.mi->seq[i].name, pl.mi->seq[i].len);
 
 	kt_pipeline(2, worker_pipeline, &pl, 3);

minimap.h

@@ -301,6 +301,8 @@ mm_tbuf_t *mm_tbuf_init(void);
  */
 void mm_tbuf_destroy(mm_tbuf_t *b);
 
+void *mm_tbuf_get_km(mm_tbuf_t *b);
+
 /**
  * Align a query sequence against an index
  *
@@ -337,6 +339,22 @@ int mm_map_file(const mm_idx_t *idx, const char *fn, const mm_mapopt_t *opt, int
 
 int mm_map_file_frag(const mm_idx_t *idx, int n_segs, const char **fn, const mm_mapopt_t *opt, int n_threads);
 
+/**
+ * Generate the cs tag (new in 2.12)
+ *
+ * @param km         memory blocks; set to NULL if unsure
+ * @param buf        buffer to write the cs/MD tag; typicall NULL on the first call
+ * @param max_len    max length of the buffer; typically set to 0 on the first call
+ * @param mi         index
+ * @param r          alignment
+ * @param seq        query sequence
+ * @param no_iden    true to use : instead of =
+ *
+ * @return the length of cs
+ */
+int mm_gen_cs(void *km, char **buf, int *max_len, const mm_idx_t *mi, const mm_reg1_t *r, const char *seq, int no_iden);
+int mm_gen_MD(void *km, char **buf, int *max_len, const mm_idx_t *mi, const mm_reg1_t *r, const char *seq);
+
 // query sequence name and sequence in the minimap2 index
 int mm_idx_index_name(mm_idx_t *mi);
 int mm_idx_name2id(const mm_idx_t *mi, const char *name);

options.c

@@ -132,6 +132,11 @@ int mm_set_opt(const char *preset, mm_idxopt_t *io, mm_mapopt_t *mo)
 
 int mm_check_opt(const mm_idxopt_t *io, const mm_mapopt_t *mo)
 {
+	if (mo->split_prefix && (mo->flag & (MM_F_OUT_CS|MM_F_OUT_MD))) {
+		if (mm_verbose >= 1)
+			fprintf(stderr, "[ERROR]\033[1;31m --cs or --MD doesn't work with --split-prefix\033[0m\n");
+		return -6;
+	}
 	if (io->k <= 0 || io->w <= 0) {
 		if (mm_verbose >= 1)
 			fprintf(stderr, "[ERROR]\033[1;31m -k and -w must be positive\033[0m\n");

python/README.rst

@@ -43,7 +43,7 @@ The following Python script demonstrates the key functionality of mappy:
 APIs
 ----
 
-Mappy implements two classes and one global function.
+Mappy implements two classes and two global function.
 
 Class mappy.Aligner
 ~~~~~~~~~~~~~~~~~~~
@@ -83,13 +83,15 @@ This constructor accepts the following arguments:
 
 .. code:: python
 
-	mappy.Aligner.map(seq, seq2=None)
+	mappy.Aligner.map(seq, seq2=None, cs=False, MD=False)
 
 This method aligns :code:`seq` against the index. It is a generator, *yielding*
 a series of :code:`mappy.Alignment` objects. If :code:`seq2` is present, mappy
 performs paired-end alignment, assuming the two ends are in the FR orientation.
 Alignments of the two ends can be distinguished by the :code:`read_num` field
-(see Class mappy.Alignment below).
+(see Class mappy.Alignment below). Argument :code:`cs` asks mappy to generate
+the :code:`cs` tag; :code:`MD` is similar. These two arguments might slightly
+degrade performance and are not enabled by default.
 
 .. code:: python
 
@@ -139,6 +141,11 @@ properties:
 * **cigar**: CIGAR returned as an array of shape :code:`(n_cigar,2)`. The two
   numbers give the length and the operator of each CIGAR operation.
 
+* **MD**: the :code:`MD` tag as in the SAM format. It is an empty string unless
+  the :code:`MD` argument is applied when calling :code:`mappy.Aligner.map()`.
+
+* **cs**: the :code:`cs` tag.
+
 An :code:`Alignment` object can be converted to a string with :code:`str()` in
 the following format:
 

python/cmappy.h

@@ -126,8 +126,8 @@ static char *mappy_fetch_seq(const mm_idx_t *mi, const char *name, int st, int e
 	*len = 0;
 	rid = mm_idx_name2id(mi, name);
 	if (rid < 0) return 0;
-	if (st >= mi->seq[rid].len || st >= en) return 0;
+	if ((uint32_t)st >= mi->seq[rid].len || st >= en) return 0;
-	if (en < 0 || en > mi->seq[rid].len)
+	if (en < 0 || (uint32_t)en > mi->seq[rid].len)
 		en = mi->seq[rid].len;
 	s = (char*)malloc(en - st + 1);
 	*len = mm_idx_getseq(mi, rid, st, en, (uint8_t*)s);

python/cmappy.pxd

@@ -40,6 +40,7 @@ cdef extern from "minimap.h":
 		int32_t mid_occ
 		int32_t max_occ
 		int mini_batch_size
+		const char *split_prefix
 
 	int mm_set_opt(char *preset, mm_idxopt_t *io, mm_mapopt_t *mo)
 	int mm_verbose
@@ -86,6 +87,9 @@ cdef extern from "minimap.h":
 
 	mm_tbuf_t *mm_tbuf_init()
 	void mm_tbuf_destroy(mm_tbuf_t *b)
+	void *mm_tbuf_get_km(mm_tbuf_t *b)
+	int mm_gen_cs(void *km, char **buf, int *max_len, const mm_idx_t *mi, const mm_reg1_t *r, const char *seq, int no_iden)
+	int mm_gen_MD(void *km, char **buf, int *max_len, const mm_idx_t *mi, const mm_reg1_t *r, const char *seq)
 
 #
 # Helper header (because it is hard to expose mm_reg1_t with Cython)

python/mappy.pyx

@@ -14,9 +14,9 @@ cdef class Alignment:
 	cdef int8_t _strand, _trans_strand
 	cdef uint8_t _mapq, _is_primary
 	cdef int _seg_id
-	cdef _ctg, _cigar # these are python objects
+	cdef _ctg, _cigar, _cs, _MD # these are python objects
 
-	def __cinit__(self, ctg, cl, cs, ce, strand, qs, qe, mapq, cigar, is_primary, mlen, blen, NM, trans_strand, seg_id):
+	def __cinit__(self, ctg, cl, cs, ce, strand, qs, qe, mapq, cigar, is_primary, mlen, blen, NM, trans_strand, seg_id, cs_str, MD_str):
 		self._ctg = ctg if isinstance(ctg, str) else ctg.decode()
 		self._ctg_len, self._r_st, self._r_en = cl, cs, ce
 		self._strand, self._q_st, self._q_en = strand, qs, qe
@@ -26,6 +26,8 @@ cdef class Alignment:
 		self._is_primary = is_primary
 		self._trans_strand = trans_strand
 		self._seg_id = seg_id
+		self._cs = cs_str
+		self._MD = MD_str
 
 	@property
 	def ctg(self): return self._ctg
@@ -72,6 +74,12 @@ cdef class Alignment:
 	@property
 	def read_num(self): return self._seg_id + 1
 
+	@property
+	def cs(self): return self._cs
+
+	@property
+	def MD(self): return self._MD
+
 	@property
 	def cigar_str(self):
 		return "".join(map(lambda x: str(x[0]) + 'MIDNSH'[x[1]], self._cigar))
@@ -85,8 +93,10 @@ cdef class Alignment:
 		if self._trans_strand > 0: ts = 'ts:A:+'
 		elif self._trans_strand < 0: ts = 'ts:A:-'
 		else: ts = 'ts:A:.'
-		return "\t".join([str(self._q_st), str(self._q_en), strand, self._ctg, str(self._ctg_len), str(self._r_st), str(self._r_en),
+		a = [str(self._q_st), str(self._q_en), strand, self._ctg, str(self._ctg_len), str(self._r_st), str(self._r_en),
-				str(self._mlen), str(self._blen), str(self._mapq), tp, ts, "cg:Z:" + self.cigar_str])
+			str(self._mlen), str(self._blen), str(self._mapq), tp, ts, "cg:Z:" + self.cigar_str]
+		if self._cs != "": a.append("cs:Z:" + self._cs)
+		return "\t".join(a)
 
 cdef class ThreadBuffer:
 	cdef cmappy.mm_tbuf_t *_b
@@ -135,18 +145,23 @@ cdef class Aligner:
 	def __bool__(self):
 		return (self._idx != NULL)
 
-	def map(self, seq, seq2=None, buf=None, max_frag_len=None):
+	def map(self, seq, seq2=None, buf=None, cs=False, MD=False, max_frag_len=None):
 		cdef cmappy.mm_reg1_t *regs
 		cdef cmappy.mm_hitpy_t h
 		cdef ThreadBuffer b
 		cdef int n_regs
+		cdef char *cs_str = NULL
+		cdef int l_cs_str, m_cs_str = 0
+		cdef void *km
 		cdef cmappy.mm_mapopt_t map_opt
+
 		map_opt = self.map_opt
 		if max_frag_len is not None: map_opt.max_frag_len = max_frag_len
 
 		if self._idx is NULL: return None
 		if buf is None: b = ThreadBuffer()
 		else: b = buf
+		km = cmappy.mm_tbuf_get_km(b._b)
 
 		_seq = seq if isinstance(seq, bytes) else seq.encode()
 		if seq2 is None:
@@ -157,13 +172,21 @@ cdef class Aligner:
 
 		for i in range(n_regs):
 			cmappy.mm_reg2hitpy(self._idx, &regs[i], &h)
-			cigar = []
+			cigar, _cs, _MD = [], '', ''
-			for k in range(h.n_cigar32):
+			for k in range(h.n_cigar32): # convert the 32-bit CIGAR encoding to Python array
 				c = h.cigar32[k]
 				cigar.append([c>>4, c&0xf])
-			yield Alignment(h.ctg, h.ctg_len, h.ctg_start, h.ctg_end, h.strand, h.qry_start, h.qry_end, h.mapq, cigar, h.is_primary, h.mlen, h.blen, h.NM, h.trans_strand, h.seg_id)
+			if cs or MD: # generate the cs and/or the MD tag, if requested
+				if cs:
+					l_cs_str = cmappy.mm_gen_cs(km, &cs_str, &m_cs_str, self._idx, &regs[i], _seq, 1)
+					_cs = cs_str[:l_cs_str] if isinstance(cs_str, str) else cs_str[:l_cs_str].decode()
+				if MD:
+					l_cs_str = cmappy.mm_gen_MD(km, &cs_str, &m_cs_str, self._idx, &regs[i], _seq)
+					_MD = cs_str[:l_cs_str] if isinstance(cs_str, str) else cs_str[:l_cs_str].decode()
+			yield Alignment(h.ctg, h.ctg_len, h.ctg_start, h.ctg_end, h.strand, h.qry_start, h.qry_end, h.mapq, cigar, h.is_primary, h.mlen, h.blen, h.NM, h.trans_strand, h.seg_id, _cs, _MD)
 			cmappy.mm_free_reg1(&regs[i])
 		free(regs)
+		free(cs_str)
 
 	def seq(self, str name, int start=0, int end=0x7fffffff):
 		cdef int l

python/minimap2.py

@@ -4,7 +4,7 @@ import sys, getopt
 import mappy as mp
 
 def main(argv):
-	opts, args = getopt.getopt(argv[1:], "x:n:m:k:w:r:")
+	opts, args = getopt.getopt(argv[1:], "x:n:m:k:w:r:c")
 	if len(args) < 2:
 		print("Usage: minimap2.py [options] <ref.fa>|<ref.mmi> <query.fq>")
 		print("Options:")
@@ -14,9 +14,10 @@ def main(argv):
 		print("  -k INT      k-mer length")
 		print("  -w INT      minimizer window length")
 		print("  -r INT      band width")
+		print("  -c          output the cs tag")
 		sys.exit(1)
 
-	preset, min_cnt, min_sc, k, w, bw = None, None, None, None, None, None
+	preset, min_cnt, min_sc, k, w, bw, out_cs = None, None, None, None, None, None, False
 	for opt, arg in opts:
 		if opt == '-x': preset = arg
 		elif opt == '-n': min_cnt = int(arg)
@@ -24,11 +25,12 @@ def main(argv):
 		elif opt == '-r': bw = int(arg)
 		elif opt == '-k': k = int(arg)
 		elif opt == '-w': w = int(arg)
+		elif opt == '-c': out_cs = True
 
 	a = mp.Aligner(args[0], preset=preset, min_cnt=min_cnt, min_chain_score=min_sc, k=k, w=w, bw=bw)
 	if not a: raise Exception("ERROR: failed to load/build index file '{}'".format(args[0]))
 	for name, seq, qual in mp.fastx_read(args[1]): # read one sequence
-		for h in a.map(seq): # traverse hits
+		for h in a.map(seq, cs=out_cs): # traverse hits
 			print('{}\t{}\t{}'.format(name, len(seq), h))
 
 if __name__ == "__main__":

setup.py

@@ -35,7 +35,7 @@ setup(
     ext_modules = [Extension('mappy',
 		sources = [module_src, 'align.c', 'bseq.c', 'chain.c', 'format.c', 'hit.c', 'index.c', 'pe.c', 'options.c',
 				   'ksw2_extd2_sse.c', 'ksw2_exts2_sse.c', 'ksw2_extz2_sse.c', 'ksw2_ll_sse.c',
-				   'kalloc.c', 'kthread.c', 'map.c', 'misc.c', 'sdust.c', 'sketch.c', 'esterr.c'],
+				   'kalloc.c', 'kthread.c', 'map.c', 'misc.c', 'sdust.c', 'sketch.c', 'esterr.c', 'splitidx.c'],
 		depends = ['minimap.h', 'bseq.h', 'kalloc.h', 'kdq.h', 'khash.h', 'kseq.h', 'ksort.h',
 				   'ksw2.h', 'kthread.h', 'kvec.h', 'mmpriv.h', 'sdust.h',
 				   'python/cmappy.h', 'python/cmappy.pxd'],