Beispiel #1
0
static int mplp_func(void *data, bam1_t *b)
{
    extern int bam_realn(bam1_t *b, const char *ref);
    extern int bam_prob_realn_core(bam1_t *b, const char *ref, int ref_len, int flag);
    extern int bam_cap_mapQ(bam1_t *b, char *ref, int ref_len, int thres);
    char *ref;
    mplp_aux_t *ma = (mplp_aux_t*)data;
    int ret, skip = 0, ref_len;
    do {
        int has_ref;
        ret = ma->iter? sam_itr_next(ma->fp, ma->iter, b) : sam_read1(ma->fp, ma->h, b);
        if (ret < 0) break;
        // The 'B' cigar operation is not part of the specification, considering as obsolete.
        //  bam_remove_B(b);
        if (b->core.tid < 0 || (b->core.flag&BAM_FUNMAP)) { // exclude unmapped reads
            skip = 1;
            continue;
        }
        if (ma->conf->rflag_require && !(ma->conf->rflag_require&b->core.flag)) { skip = 1; continue; }
        if (ma->conf->rflag_filter && ma->conf->rflag_filter&b->core.flag) { skip = 1; continue; }
        if (ma->conf->bed) { // test overlap
            skip = !bed_overlap(ma->conf->bed, ma->h->target_name[b->core.tid], b->core.pos, bam_endpos(b));
            if (skip) continue;
        }
        if (ma->conf->rghash) { // exclude read groups
            uint8_t *rg = bam_aux_get(b, "RG");
            skip = (rg && khash_str2int_get(ma->conf->rghash, (const char*)(rg+1), NULL)==0);
            if (skip) continue;
        }
        if (ma->conf->flag & MPLP_ILLUMINA13) {
            int i;
            uint8_t *qual = bam_get_qual(b);
            for (i = 0; i < b->core.l_qseq; ++i)
                qual[i] = qual[i] > 31? qual[i] - 31 : 0;
        }

        if (ma->conf->fai && b->core.tid >= 0) {
            has_ref = mplp_get_ref(ma, b->core.tid, &ref, &ref_len);
            if (has_ref && ref_len <= b->core.pos) { // exclude reads outside of the reference sequence
                fprintf(stderr,"[%s] Skipping because %d is outside of %d [ref:%d]\n",
                        __func__, b->core.pos, ref_len, b->core.tid);
                skip = 1;
                continue;
            }
        } else {
            has_ref = 0;
        }

        skip = 0;
        if (has_ref && (ma->conf->flag&MPLP_REALN)) bam_prob_realn_core(b, ref, ref_len, (ma->conf->flag & MPLP_REDO_BAQ)? 7 : 3);
        if (has_ref && ma->conf->capQ_thres > 10) {
            int q = bam_cap_mapQ(b, ref, ref_len, ma->conf->capQ_thres);
            if (q < 0) skip = 1;
            else if (b->core.qual > q) b->core.qual = q;
        }
        if (b->core.qual < ma->conf->min_mq) skip = 1;
        else if ((ma->conf->flag&MPLP_NO_ORPHAN) && (b->core.flag&BAM_FPAIRED) && !(b->core.flag&BAM_FPROPER_PAIR)) skip = 1;
    } while (skip);
    return ret;
}
Beispiel #2
0
static int mpileup_reg(mplp_conf_t *conf, uint32_t beg, uint32_t end)
{
    bam_hdr_t *hdr = conf->mplp_data[0]->h; // header of first file in input list

    int ret, i, tid, pos, ref_len;
    char *ref;

    while ( (ret=bam_mplp_auto(conf->iter, &tid, &pos, conf->n_plp, conf->plp)) > 0) 
    {
        if ( end && (pos<beg || pos>end) ) continue;
        if ( conf->bed && tid >= 0 )
        {
            int overlap = regidx_overlap(conf->bed, hdr->target_name[tid], pos, pos, NULL);
            if ( !conf->bed_logic ) overlap = overlap ? 0 : 1;
            if ( !overlap ) continue;
        }
        mplp_get_ref(conf->mplp_data[0], tid, &ref, &ref_len);

        int total_depth, _ref0, ref16;
        for (i = total_depth = 0; i < conf->nfiles; ++i) total_depth += conf->n_plp[i];
        group_smpl(conf->gplp, conf->bsmpl, conf->nfiles, conf->n_plp, conf->plp);
        _ref0 = (ref && pos < ref_len)? ref[pos] : 'N';
        ref16 = seq_nt16_table[_ref0];
        bcf_callaux_clean(conf->bca, &conf->bc);
        for (i = 0; i < conf->gplp->n; ++i)
            bcf_call_glfgen(conf->gplp->n_plp[i], conf->gplp->plp[i], ref16, conf->bca, conf->bcr + i);
        conf->bc.tid = tid; conf->bc.pos = pos;
        bcf_call_combine(conf->gplp->n, conf->bcr, conf->bca, ref16, &conf->bc);
        bcf_clear1(conf->bcf_rec);
        bcf_call2bcf(&conf->bc, conf->bcf_rec, conf->bcr, conf->fmt_flag, 0, 0);
        flush_bcf_records(conf, conf->bcf_fp, conf->bcf_hdr, conf->bcf_rec);

        // call indels; todo: subsampling with total_depth>max_indel_depth instead of ignoring?
        // check me: rghash in bcf_call_gap_prep() should have no effect, reads mplp_func already excludes them
        if (!(conf->flag&MPLP_NO_INDEL) && total_depth < conf->max_indel_depth 
            && bcf_call_gap_prep(conf->gplp->n, conf->gplp->n_plp, conf->gplp->plp, pos, conf->bca, ref) >= 0)
        {
            bcf_callaux_clean(conf->bca, &conf->bc);
            for (i = 0; i < conf->gplp->n; ++i)
                bcf_call_glfgen(conf->gplp->n_plp[i], conf->gplp->plp[i], -1, conf->bca, conf->bcr + i);
            if (bcf_call_combine(conf->gplp->n, conf->bcr, conf->bca, -1, &conf->bc) >= 0) 
            {
                bcf_clear1(conf->bcf_rec);
                bcf_call2bcf(&conf->bc, conf->bcf_rec, conf->bcr, conf->fmt_flag, conf->bca, ref);
                flush_bcf_records(conf, conf->bcf_fp, conf->bcf_hdr, conf->bcf_rec);
            }
        }
    }
    return 0;
}
Beispiel #3
0
static int mplp_func(void *data, bam1_t *b)
{
    char *ref;
    mplp_aux_t *ma = (mplp_aux_t*)data;
    int ret, ref_len;
    while (1)
    {
        int has_ref;
        ret = ma->iter? sam_itr_next(ma->fp, ma->iter, b) : sam_read1(ma->fp, ma->h, b);
        if (ret < 0) break;
        // The 'B' cigar operation is not part of the specification, considering as obsolete.
        //  bam_remove_B(b);
        if (b->core.tid < 0 || (b->core.flag&BAM_FUNMAP)) continue; // exclude unmapped reads
        if (ma->conf->rflag_require && !(ma->conf->rflag_require&b->core.flag)) continue;
        if (ma->conf->rflag_filter && ma->conf->rflag_filter&b->core.flag) continue;
        if (ma->conf->bed)
        {
            // test overlap
            regitr_t *itr = ma->conf->bed_itr;
            int beg = b->core.pos, end = bam_endpos(b)-1;
            int overlap = regidx_overlap(ma->conf->bed, ma->h->target_name[b->core.tid],beg,end, itr);
            if ( !ma->conf->bed_logic && !overlap )
            {
                // exclude only reads which are fully contained in the region
                while ( regitr_overlap(itr) )
                {
                    if ( beg < itr->beg ) { overlap = 1; break; }
                    if ( end > itr->end ) { overlap = 1; break; }
                }
            }
            if ( !overlap ) continue;
        }
        if ( bam_smpl_get_sample_id(ma->conf->bsmpl,ma->bam_id,b)<0 ) continue;
        if (ma->conf->flag & MPLP_ILLUMINA13) {
            int i;
            uint8_t *qual = bam_get_qual(b);
            for (i = 0; i < b->core.l_qseq; ++i)
                qual[i] = qual[i] > 31? qual[i] - 31 : 0;
        }

        if (ma->conf->fai && b->core.tid >= 0) {
            has_ref = mplp_get_ref(ma, b->core.tid, &ref, &ref_len);
            if (has_ref && ref_len <= b->core.pos) { // exclude reads outside of the reference sequence
                fprintf(stderr,"[%s] Skipping because %d is outside of %d [ref:%d]\n",
                        __func__, b->core.pos, ref_len, b->core.tid);
                continue;
            }
        } else {
            has_ref = 0;
        }

        if (has_ref && (ma->conf->flag&MPLP_REALN)) sam_prob_realn(b, ref, ref_len, (ma->conf->flag & MPLP_REDO_BAQ)? 7 : 3);
        if (has_ref && ma->conf->capQ_thres > 10) {
            int q = sam_cap_mapq(b, ref, ref_len, ma->conf->capQ_thres);
            if (q < 0) continue;    // skip
            else if (b->core.qual > q) b->core.qual = q;
        }
        if (b->core.qual < ma->conf->min_mq) continue;
        else if ((ma->conf->flag&MPLP_NO_ORPHAN) && (b->core.flag&BAM_FPAIRED) && !(b->core.flag&BAM_FPROPER_PAIR)) continue;

        return ret;
    };
    return ret;
}
Beispiel #4
0
/*
 * Performs pileup
 * @param conf configuration for this pileup
 * @param n number of files specified in fn
 * @param fn filenames
 */
static int mpileup(mplp_conf_t *conf, int n, char **fn)
{
    extern void *bcf_call_add_rg(void *rghash, const char *hdtext, const char *list);
    extern void bcf_call_del_rghash(void *rghash);
    mplp_aux_t **data;
    int i, tid, pos, *n_plp, beg0 = 0, end0 = INT_MAX, ref_len, max_depth, max_indel_depth;
    const bam_pileup1_t **plp;
    mplp_ref_t mp_ref = MPLP_REF_INIT;
    bam_mplp_t iter;
    bam_hdr_t *h = NULL; /* header of first file in input list */
    char *ref;
    void *rghash = NULL;
    FILE *pileup_fp = NULL;

    bcf_callaux_t *bca = NULL;
    bcf_callret1_t *bcr = NULL;
    bcf_call_t bc;
    htsFile *bcf_fp = NULL;
    bcf_hdr_t *bcf_hdr = NULL;

    bam_sample_t *sm = NULL;
    kstring_t buf;
    mplp_pileup_t gplp;

    memset(&gplp, 0, sizeof(mplp_pileup_t));
    memset(&buf, 0, sizeof(kstring_t));
    memset(&bc, 0, sizeof(bcf_call_t));
    data = calloc(n, sizeof(mplp_aux_t*));
    plp = calloc(n, sizeof(bam_pileup1_t*));
    n_plp = calloc(n, sizeof(int));
    sm = bam_smpl_init();

    if (n == 0) {
        fprintf(stderr,"[%s] no input file/data given\n", __func__);
        exit(EXIT_FAILURE);
    }

    // read the header of each file in the list and initialize data
    for (i = 0; i < n; ++i) {
        bam_hdr_t *h_tmp;
        data[i] = calloc(1, sizeof(mplp_aux_t));
        data[i]->fp = sam_open(fn[i], "rb");
        if ( !data[i]->fp )
        {
            fprintf(stderr, "[%s] failed to open %s: %s\n", __func__, fn[i], strerror(errno));
            exit(EXIT_FAILURE);
        }
        if (hts_set_opt(data[i]->fp, CRAM_OPT_DECODE_MD, 0)) {
            fprintf(stderr, "Failed to set CRAM_OPT_DECODE_MD value\n");
            exit(EXIT_FAILURE);
        }
        if (conf->fai_fname && hts_set_fai_filename(data[i]->fp, conf->fai_fname) != 0) {
            fprintf(stderr, "[%s] failed to process %s: %s\n",
                    __func__, conf->fai_fname, strerror(errno));
            exit(EXIT_FAILURE);
        }
        data[i]->conf = conf;
        data[i]->ref = &mp_ref;
        h_tmp = sam_hdr_read(data[i]->fp);
        if ( !h_tmp ) {
            fprintf(stderr,"[%s] fail to read the header of %s\n", __func__, fn[i]);
            exit(EXIT_FAILURE);
        }
        bam_smpl_add(sm, fn[i], (conf->flag&MPLP_IGNORE_RG)? 0 : h_tmp->text);
        // Collect read group IDs with PL (platform) listed in pl_list (note: fragile, strstr search)
        rghash = bcf_call_add_rg(rghash, h_tmp->text, conf->pl_list);
        if (conf->reg) {
            hts_idx_t *idx = sam_index_load(data[i]->fp, fn[i]);
            if (idx == NULL) {
                fprintf(stderr, "[%s] fail to load index for %s\n", __func__, fn[i]);
                exit(EXIT_FAILURE);
            }
            if ( (data[i]->iter=sam_itr_querys(idx, h_tmp, conf->reg)) == 0) {
                fprintf(stderr, "[E::%s] fail to parse region '%s' with %s\n", __func__, conf->reg, fn[i]);
                exit(EXIT_FAILURE);
            }
            if (i == 0) beg0 = data[i]->iter->beg, end0 = data[i]->iter->end;
            hts_idx_destroy(idx);
        }
        else
            data[i]->iter = NULL;

        if (i == 0) h = data[i]->h = h_tmp; // save the header of the first file
        else {
            // FIXME: check consistency between h and h_tmp
            bam_hdr_destroy(h_tmp);

            // we store only the first file's header; it's (alleged to be)
            // compatible with the i-th file's target_name lookup needs
            data[i]->h = h;
        }
    }
    // allocate data storage proportionate to number of samples being studied sm->n
    gplp.n = sm->n;
    gplp.n_plp = calloc(sm->n, sizeof(int));
    gplp.m_plp = calloc(sm->n, sizeof(int));
    gplp.plp = calloc(sm->n, sizeof(bam_pileup1_t*));

    fprintf(stderr, "[%s] %d samples in %d input files\n", __func__, sm->n, n);
    // write the VCF header
    if (conf->flag & MPLP_BCF)
    {
        const char *mode;
        if ( conf->flag & MPLP_VCF )
            mode = (conf->flag&MPLP_NO_COMP)? "wu" : "wz";   // uncompressed VCF or compressed VCF
        else
            mode = (conf->flag&MPLP_NO_COMP)? "wub" : "wb";  // uncompressed BCF or compressed BCF

        bcf_fp = bcf_open(conf->output_fname? conf->output_fname : "-", mode);
        if (bcf_fp == NULL) {
            fprintf(stderr, "[%s] failed to write to %s: %s\n", __func__, conf->output_fname? conf->output_fname : "standard output", strerror(errno));
            exit(EXIT_FAILURE);
        }

        // BCF header creation
        bcf_hdr = bcf_hdr_init("w");
        kstring_t str = {0,0,NULL};

        ksprintf(&str, "##samtoolsVersion=%s+htslib-%s\n",samtools_version(),hts_version());
        bcf_hdr_append(bcf_hdr, str.s);

        str.l = 0;
        ksprintf(&str, "##samtoolsCommand=samtools mpileup");
        for (i=1; i<conf->argc; i++) ksprintf(&str, " %s", conf->argv[i]);
        kputc('\n', &str);
        bcf_hdr_append(bcf_hdr, str.s);

        if (conf->fai_fname)
        {
            str.l = 0;
            ksprintf(&str, "##reference=file://%s\n", conf->fai_fname);
            bcf_hdr_append(bcf_hdr, str.s);
        }

        // Translate BAM @SQ tags to BCF ##contig tags
        // todo: use/write new BAM header manipulation routines, fill also UR, M5
        for (i=0; i<h->n_targets; i++)
        {
            str.l = 0;
            ksprintf(&str, "##contig=<ID=%s,length=%d>", h->target_name[i], h->target_len[i]);
            bcf_hdr_append(bcf_hdr, str.s);
        }
        free(str.s);
        bcf_hdr_append(bcf_hdr,"##ALT=<ID=X,Description=\"Represents allele(s) other than observed.\">");
        bcf_hdr_append(bcf_hdr,"##INFO=<ID=INDEL,Number=0,Type=Flag,Description=\"Indicates that the variant is an INDEL.\">");
        bcf_hdr_append(bcf_hdr,"##INFO=<ID=IDV,Number=1,Type=Integer,Description=\"Maximum number of reads supporting an indel\">");
        bcf_hdr_append(bcf_hdr,"##INFO=<ID=IMF,Number=1,Type=Float,Description=\"Maximum fraction of reads supporting an indel\">");
        bcf_hdr_append(bcf_hdr,"##INFO=<ID=DP,Number=1,Type=Integer,Description=\"Raw read depth\">");
        bcf_hdr_append(bcf_hdr,"##INFO=<ID=VDB,Number=1,Type=Float,Description=\"Variant Distance Bias for filtering splice-site artefacts in RNA-seq data (bigger is better)\",Version=\"3\">");
        bcf_hdr_append(bcf_hdr,"##INFO=<ID=RPB,Number=1,Type=Float,Description=\"Mann-Whitney U test of Read Position Bias (bigger is better)\">");
        bcf_hdr_append(bcf_hdr,"##INFO=<ID=MQB,Number=1,Type=Float,Description=\"Mann-Whitney U test of Mapping Quality Bias (bigger is better)\">");
        bcf_hdr_append(bcf_hdr,"##INFO=<ID=BQB,Number=1,Type=Float,Description=\"Mann-Whitney U test of Base Quality Bias (bigger is better)\">");
        bcf_hdr_append(bcf_hdr,"##INFO=<ID=MQSB,Number=1,Type=Float,Description=\"Mann-Whitney U test of Mapping Quality vs Strand Bias (bigger is better)\">");
#if CDF_MWU_TESTS
        bcf_hdr_append(bcf_hdr,"##INFO=<ID=RPB2,Number=1,Type=Float,Description=\"Mann-Whitney U test of Read Position Bias [CDF] (bigger is better)\">");
        bcf_hdr_append(bcf_hdr,"##INFO=<ID=MQB2,Number=1,Type=Float,Description=\"Mann-Whitney U test of Mapping Quality Bias [CDF] (bigger is better)\">");
        bcf_hdr_append(bcf_hdr,"##INFO=<ID=BQB2,Number=1,Type=Float,Description=\"Mann-Whitney U test of Base Quality Bias [CDF] (bigger is better)\">");
        bcf_hdr_append(bcf_hdr,"##INFO=<ID=MQSB2,Number=1,Type=Float,Description=\"Mann-Whitney U test of Mapping Quality vs Strand Bias [CDF] (bigger is better)\">");
#endif
        bcf_hdr_append(bcf_hdr,"##INFO=<ID=SGB,Number=1,Type=Float,Description=\"Segregation based metric.\">");
        bcf_hdr_append(bcf_hdr,"##INFO=<ID=MQ0F,Number=1,Type=Float,Description=\"Fraction of MQ0 reads (smaller is better)\">");
        bcf_hdr_append(bcf_hdr,"##INFO=<ID=I16,Number=16,Type=Float,Description=\"Auxiliary tag used for calling, see description of bcf_callret1_t in bam2bcf.h\">");
        bcf_hdr_append(bcf_hdr,"##INFO=<ID=QS,Number=R,Type=Float,Description=\"Auxiliary tag used for calling\">");
        bcf_hdr_append(bcf_hdr,"##FORMAT=<ID=PL,Number=G,Type=Integer,Description=\"List of Phred-scaled genotype likelihoods\">");
        if ( conf->fmt_flag&B2B_FMT_DP )
            bcf_hdr_append(bcf_hdr,"##FORMAT=<ID=DP,Number=1,Type=Integer,Description=\"Number of high-quality bases\">");
        if ( conf->fmt_flag&B2B_FMT_DV )
            bcf_hdr_append(bcf_hdr,"##FORMAT=<ID=DV,Number=1,Type=Integer,Description=\"Number of high-quality non-reference bases\">");
        if ( conf->fmt_flag&B2B_FMT_DPR )
            bcf_hdr_append(bcf_hdr,"##FORMAT=<ID=DPR,Number=R,Type=Integer,Description=\"Number of high-quality bases observed for each allele\">");
        if ( conf->fmt_flag&B2B_INFO_DPR )
            bcf_hdr_append(bcf_hdr,"##INFO=<ID=DPR,Number=R,Type=Integer,Description=\"Number of high-quality bases observed for each allele\">");
        if ( conf->fmt_flag&B2B_FMT_DP4 )
            bcf_hdr_append(bcf_hdr,"##FORMAT=<ID=DP4,Number=4,Type=Integer,Description=\"Number of high-quality ref-fwd, ref-reverse, alt-fwd and alt-reverse bases\">");
        if ( conf->fmt_flag&B2B_FMT_SP )
            bcf_hdr_append(bcf_hdr,"##FORMAT=<ID=SP,Number=1,Type=Integer,Description=\"Phred-scaled strand bias P-value\">");

        for (i=0; i<sm->n; i++)
            bcf_hdr_add_sample(bcf_hdr, sm->smpl[i]);
        bcf_hdr_add_sample(bcf_hdr, NULL);
        bcf_hdr_write(bcf_fp, bcf_hdr);
        // End of BCF header creation

        // Initialise the calling algorithm
        bca = bcf_call_init(-1., conf->min_baseQ);
        bcr = calloc(sm->n, sizeof(bcf_callret1_t));
        bca->rghash = rghash;
        bca->openQ = conf->openQ, bca->extQ = conf->extQ, bca->tandemQ = conf->tandemQ;
        bca->min_frac = conf->min_frac;
        bca->min_support = conf->min_support;
        bca->per_sample_flt = conf->flag & MPLP_PER_SAMPLE;

        bc.bcf_hdr = bcf_hdr;
        bc.n = sm->n;
        bc.PL = malloc(15 * sm->n * sizeof(*bc.PL));
        if (conf->fmt_flag)
        {
            assert( sizeof(float)==sizeof(int32_t) );
            bc.DP4 = malloc(sm->n * sizeof(int32_t) * 4);
            bc.fmt_arr = malloc(sm->n * sizeof(float)); // all fmt_flag fields
            if ( conf->fmt_flag&(B2B_INFO_DPR|B2B_FMT_DPR) )
            {
                // first B2B_MAX_ALLELES fields for total numbers, the rest per-sample
                bc.DPR = malloc((sm->n+1)*B2B_MAX_ALLELES*sizeof(int32_t));
                for (i=0; i<sm->n; i++)
                    bcr[i].DPR = bc.DPR + (i+1)*B2B_MAX_ALLELES;
            }
        }
    }
    else {
        pileup_fp = conf->output_fname? fopen(conf->output_fname, "w") : stdout;

        if (pileup_fp == NULL) {
            fprintf(stderr, "[%s] failed to write to %s: %s\n", __func__, conf->output_fname, strerror(errno));
            exit(EXIT_FAILURE);
        }
    }

    // init pileup
    iter = bam_mplp_init(n, mplp_func, (void**)data);
    if ( conf->flag & MPLP_SMART_OVERLAPS ) bam_mplp_init_overlaps(iter);
    max_depth = conf->max_depth;
    if (max_depth * sm->n > 1<<20)
        fprintf(stderr, "(%s) Max depth is above 1M. Potential memory hog!\n", __func__);
    if (max_depth * sm->n < 8000) {
        max_depth = 8000 / sm->n;
        fprintf(stderr, "<%s> Set max per-file depth to %d\n", __func__, max_depth);
    }
    max_indel_depth = conf->max_indel_depth * sm->n;
    bam_mplp_set_maxcnt(iter, max_depth);
    bcf1_t *bcf_rec = bcf_init1();
    int ret;
    // begin pileup
    while ( (ret=bam_mplp_auto(iter, &tid, &pos, n_plp, plp)) > 0) {
        if (conf->reg && (pos < beg0 || pos >= end0)) continue; // out of the region requested
        if (conf->bed && tid >= 0 && !bed_overlap(conf->bed, h->target_name[tid], pos, pos+1)) continue;
        mplp_get_ref(data[0], tid, &ref, &ref_len);
        //printf("tid=%d len=%d ref=%p/%s\n", tid, ref_len, ref, ref);
        if (conf->flag & MPLP_BCF) {
            int total_depth, _ref0, ref16;
            for (i = total_depth = 0; i < n; ++i) total_depth += n_plp[i];
            group_smpl(&gplp, sm, &buf, n, fn, n_plp, plp, conf->flag & MPLP_IGNORE_RG);
            _ref0 = (ref && pos < ref_len)? ref[pos] : 'N';
            ref16 = seq_nt16_table[_ref0];
            bcf_callaux_clean(bca, &bc);
            for (i = 0; i < gplp.n; ++i)
                bcf_call_glfgen(gplp.n_plp[i], gplp.plp[i], ref16, bca, bcr + i);
            bc.tid = tid; bc.pos = pos;
            bcf_call_combine(gplp.n, bcr, bca, ref16, &bc);
            bcf_clear1(bcf_rec);
            bcf_call2bcf(&bc, bcf_rec, bcr, conf->fmt_flag, 0, 0);
            bcf_write1(bcf_fp, bcf_hdr, bcf_rec);
            // call indels; todo: subsampling with total_depth>max_indel_depth instead of ignoring?
            if (!(conf->flag&MPLP_NO_INDEL) && total_depth < max_indel_depth && bcf_call_gap_prep(gplp.n, gplp.n_plp, gplp.plp, pos, bca, ref, rghash) >= 0)
            {
                bcf_callaux_clean(bca, &bc);
                for (i = 0; i < gplp.n; ++i)
                    bcf_call_glfgen(gplp.n_plp[i], gplp.plp[i], -1, bca, bcr + i);
                if (bcf_call_combine(gplp.n, bcr, bca, -1, &bc) >= 0) {
                    bcf_clear1(bcf_rec);
                    bcf_call2bcf(&bc, bcf_rec, bcr, conf->fmt_flag, bca, ref);
                    bcf_write1(bcf_fp, bcf_hdr, bcf_rec);
                }
            }
        } else {
            fprintf(pileup_fp, "%s\t%d\t%c", h->target_name[tid], pos + 1, (ref && pos < ref_len)? ref[pos] : 'N');
            for (i = 0; i < n; ++i) {
                int j, cnt;
                for (j = cnt = 0; j < n_plp[i]; ++j) {
                    const bam_pileup1_t *p = plp[i] + j;
                    int c = p->qpos < p->b->core.l_qseq
                             ? bam_get_qual(p->b)[p->qpos]
                             : 0;
                    if (c >= conf->min_baseQ) ++cnt;
                }
                fprintf(pileup_fp, "\t%d\t", cnt);
                if (n_plp[i] == 0) {
                    fputs("*\t*", pileup_fp);
                    if (conf->flag & MPLP_PRINT_MAPQ) fputs("\t*", pileup_fp);
                    if (conf->flag & MPLP_PRINT_POS) fputs("\t*", pileup_fp);
                } else {
                    for (j = 0; j < n_plp[i]; ++j) {
                        const bam_pileup1_t *p = plp[i] + j;
                        int c = p->qpos < p->b->core.l_qseq
                            ? bam_get_qual(p->b)[p->qpos]
                            : 0;
                        if (c >= conf->min_baseQ)
                            pileup_seq(pileup_fp, plp[i] + j, pos, ref_len, ref);
                    }
                    putc('\t', pileup_fp);
                    for (j = 0; j < n_plp[i]; ++j) {
                        const bam_pileup1_t *p = plp[i] + j;
                        int c = p->qpos < p->b->core.l_qseq
                            ? bam_get_qual(p->b)[p->qpos]
                            : 0;
                        if (c >= conf->min_baseQ) {
                            c = c + 33 < 126? c + 33 : 126;
                            putc(c, pileup_fp);
                        }
                    }
                    if (conf->flag & MPLP_PRINT_MAPQ) {
                        putc('\t', pileup_fp);
                        for (j = 0; j < n_plp[i]; ++j) {
                            const bam_pileup1_t *p = plp[i] + j;
                            int c = bam_get_qual(p->b)[p->qpos];
                            if ( c < conf->min_baseQ ) continue;
                            c = plp[i][j].b->core.qual + 33;
                            if (c > 126) c = 126;
                            putc(c, pileup_fp);
                        }
                    }
                    if (conf->flag & MPLP_PRINT_POS) {
                        putc('\t', pileup_fp);
                        for (j = 0; j < n_plp[i]; ++j) {
                            if (j > 0) putc(',', pileup_fp);
                            fprintf(pileup_fp, "%d", plp[i][j].qpos + 1); // FIXME: printf() is very slow...
                        }
                    }
                }
            }
            putc('\n', pileup_fp);
        }
    }

    // clean up
    free(bc.tmp.s);
    bcf_destroy1(bcf_rec);
    if (bcf_fp)
    {
        hts_close(bcf_fp);
        bcf_hdr_destroy(bcf_hdr);
        bcf_call_destroy(bca);
        free(bc.PL);
        free(bc.DP4);
        free(bc.DPR);
        free(bc.fmt_arr);
        free(bcr);
    }
    if (pileup_fp && conf->output_fname) fclose(pileup_fp);
    bam_smpl_destroy(sm); free(buf.s);
    for (i = 0; i < gplp.n; ++i) free(gplp.plp[i]);
    free(gplp.plp); free(gplp.n_plp); free(gplp.m_plp);
    bcf_call_del_rghash(rghash);
    bam_mplp_destroy(iter);
    bam_hdr_destroy(h);
    for (i = 0; i < n; ++i) {
        sam_close(data[i]->fp);
        if (data[i]->iter) hts_itr_destroy(data[i]->iter);
        free(data[i]);
    }
    free(data); free(plp); free(n_plp);
    if (mp_ref.ref[0]) free(mp_ref.ref[0]);
    if (mp_ref.ref[1]) free(mp_ref.ref[1]);
    return ret;
}