+#define BAM_CDIFF 8
+#define BAM_CBACK 9
+
+#define BAM_CIGAR_STR "MIDNSHP=XB"
+#define BAM_CIGAR_TYPE 0x3C1A7
+
+#define bam_cigar_op(c) ((c)&BAM_CIGAR_MASK)
+#define bam_cigar_oplen(c) ((c)>>BAM_CIGAR_SHIFT)
+#define bam_cigar_opchr(c) (BAM_CIGAR_STR[bam_cigar_op(c)])
+#define bam_cigar_gen(l, o) ((l)<<BAM_CIGAR_SHIFT|(o))
+#define bam_cigar_type(o) (BAM_CIGAR_TYPE>>((o)<<1)&3) // bit 1: consume query; bit 2: consume reference