X-Git-Url: http://woldlab.caltech.edu/gitweb/?p=pysam.git;a=blobdiff_plain;f=samtools%2Fbam_index.c.pysam.c;fp=samtools%2Fbam_index.c.pysam.c;h=e6c90bdc2d23cb47466e3ed103f820fa92a11356;hp=0000000000000000000000000000000000000000;hb=bd0c3067c187d1f718004fb38acc093af8810a02;hpb=1b740fc70684c92a5e2293013217d5a2fd661d8a diff --git a/samtools/bam_index.c.pysam.c b/samtools/bam_index.c.pysam.c new file mode 100644 index 0000000..e6c90bd --- /dev/null +++ b/samtools/bam_index.c.pysam.c @@ -0,0 +1,713 @@ +#include "pysam.h" + +#include +#include +#include "bam.h" +#include "khash.h" +#include "ksort.h" +#include "bam_endian.h" +#ifdef _USE_KNETFILE +#include "knetfile.h" +#endif + +/*! + @header + + Alignment indexing. Before indexing, BAM must be sorted based on the + leftmost coordinate of alignments. In indexing, BAM uses two indices: + a UCSC binning index and a simple linear index. The binning index is + efficient for alignments spanning long distance, while the auxiliary + linear index helps to reduce unnecessary seek calls especially for + short alignments. + + The UCSC binning scheme was suggested by Richard Durbin and Lincoln + Stein and is explained by Kent et al. (2002). In this scheme, each bin + represents a contiguous genomic region which can be fully contained in + another bin; each alignment is associated with a bin which represents + the smallest region containing the entire alignment. The binning + scheme is essentially another representation of R-tree. A distinct bin + uniquely corresponds to a distinct internal node in a R-tree. Bin A is + a child of Bin B if region A is contained in B. + + In BAM, each bin may span 2^29, 2^26, 2^23, 2^20, 2^17 or 2^14 bp. Bin + 0 spans a 512Mbp region, bins 1-8 span 64Mbp, 9-72 8Mbp, 73-584 1Mbp, + 585-4680 128Kbp and bins 4681-37449 span 16Kbp regions. If we want to + find the alignments overlapped with a region [rbeg,rend), we need to + calculate the list of bins that may be overlapped the region and test + the alignments in the bins to confirm the overlaps. If the specified + region is short, typically only a few alignments in six bins need to + be retrieved. The overlapping alignments can be quickly fetched. + + */ + +#define BAM_MIN_CHUNK_GAP 32768 +// 1<<14 is the size of minimum bin. +#define BAM_LIDX_SHIFT 14 + +#define BAM_MAX_BIN 37450 // =(8^6-1)/7+1 + +typedef struct { + uint64_t u, v; +} pair64_t; + +#define pair64_lt(a,b) ((a).u < (b).u) +KSORT_INIT(off, pair64_t, pair64_lt) + +typedef struct { + uint32_t m, n; + pair64_t *list; +} bam_binlist_t; + +typedef struct { + int32_t n, m; + uint64_t *offset; +} bam_lidx_t; + +KHASH_MAP_INIT_INT(i, bam_binlist_t) + +struct __bam_index_t { + int32_t n; + uint64_t n_no_coor; // unmapped reads without coordinate + khash_t(i) **index; + bam_lidx_t *index2; +}; + +// requirement: len <= LEN_MASK +static inline void insert_offset(khash_t(i) *h, int bin, uint64_t beg, uint64_t end) +{ + khint_t k; + bam_binlist_t *l; + int ret; + k = kh_put(i, h, bin, &ret); + l = &kh_value(h, k); + if (ret) { // not present + l->m = 1; l->n = 0; + l->list = (pair64_t*)calloc(l->m, 16); + } + if (l->n == l->m) { + l->m <<= 1; + l->list = (pair64_t*)realloc(l->list, l->m * 16); + } + l->list[l->n].u = beg; l->list[l->n++].v = end; +} + +static inline void insert_offset2(bam_lidx_t *index2, bam1_t *b, uint64_t offset) +{ + int i, beg, end; + beg = b->core.pos >> BAM_LIDX_SHIFT; + end = (bam_calend(&b->core, bam1_cigar(b)) - 1) >> BAM_LIDX_SHIFT; + if (index2->m < end + 1) { + int old_m = index2->m; + index2->m = end + 1; + kroundup32(index2->m); + index2->offset = (uint64_t*)realloc(index2->offset, index2->m * 8); + memset(index2->offset + old_m, 0, 8 * (index2->m - old_m)); + } + if (beg == end) { + if (index2->offset[beg] == 0) index2->offset[beg] = offset; + } else { + for (i = beg; i <= end; ++i) + if (index2->offset[i] == 0) index2->offset[i] = offset; + } + index2->n = end + 1; +} + +static void merge_chunks(bam_index_t *idx) +{ +#if defined(BAM_TRUE_OFFSET) || defined(BAM_VIRTUAL_OFFSET16) + khash_t(i) *index; + int i, l, m; + khint_t k; + for (i = 0; i < idx->n; ++i) { + index = idx->index[i]; + for (k = kh_begin(index); k != kh_end(index); ++k) { + bam_binlist_t *p; + if (!kh_exist(index, k) || kh_key(index, k) == BAM_MAX_BIN) continue; + p = &kh_value(index, k); + m = 0; + for (l = 1; l < p->n; ++l) { +#ifdef BAM_TRUE_OFFSET + if (p->list[m].v + BAM_MIN_CHUNK_GAP > p->list[l].u) p->list[m].v = p->list[l].v; +#else + if (p->list[m].v>>16 == p->list[l].u>>16) p->list[m].v = p->list[l].v; +#endif + else p->list[++m] = p->list[l]; + } // ~for(l) + p->n = m + 1; + } // ~for(k) + } // ~for(i) +#endif // defined(BAM_TRUE_OFFSET) || defined(BAM_BGZF) +} + +static void fill_missing(bam_index_t *idx) +{ + int i, j; + for (i = 0; i < idx->n; ++i) { + bam_lidx_t *idx2 = &idx->index2[i]; + for (j = 1; j < idx2->n; ++j) + if (idx2->offset[j] == 0) + idx2->offset[j] = idx2->offset[j-1]; + } +} + +bam_index_t *bam_index_core(bamFile fp) +{ + bam1_t *b; + bam_header_t *h; + int i, ret; + bam_index_t *idx; + uint32_t last_bin, save_bin; + int32_t last_coor, last_tid, save_tid; + bam1_core_t *c; + uint64_t save_off, last_off, n_mapped, n_unmapped, off_beg, off_end, n_no_coor; + + idx = (bam_index_t*)calloc(1, sizeof(bam_index_t)); + b = (bam1_t*)calloc(1, sizeof(bam1_t)); + h = bam_header_read(fp); + c = &b->core; + + idx->n = h->n_targets; + bam_header_destroy(h); + idx->index = (khash_t(i)**)calloc(idx->n, sizeof(void*)); + for (i = 0; i < idx->n; ++i) idx->index[i] = kh_init(i); + idx->index2 = (bam_lidx_t*)calloc(idx->n, sizeof(bam_lidx_t)); + + save_bin = save_tid = last_tid = last_bin = 0xffffffffu; + save_off = last_off = bam_tell(fp); last_coor = 0xffffffffu; + n_mapped = n_unmapped = n_no_coor = off_end = 0; + off_beg = off_end = bam_tell(fp); + while ((ret = bam_read1(fp, b)) >= 0) { + if (c->tid < 0) ++n_no_coor; + if (last_tid != c->tid) { // change of chromosomes + last_tid = c->tid; + last_bin = 0xffffffffu; + } else if (last_coor > c->pos) { + fprintf(pysamerr, "[bam_index_core] the alignment is not sorted (%s): %u > %u in %d-th chr\n", + bam1_qname(b), last_coor, c->pos, c->tid+1); + exit(1); + } + if (c->tid >= 0) insert_offset2(&idx->index2[b->core.tid], b, last_off); + if (c->bin != last_bin) { // then possibly write the binning index + if (save_bin != 0xffffffffu) // save_bin==0xffffffffu only happens to the first record + insert_offset(idx->index[save_tid], save_bin, save_off, last_off); + if (last_bin == 0xffffffffu && save_tid != 0xffffffffu) { // write the meta element + off_end = last_off; + insert_offset(idx->index[save_tid], BAM_MAX_BIN, off_beg, off_end); + insert_offset(idx->index[save_tid], BAM_MAX_BIN, n_mapped, n_unmapped); + n_mapped = n_unmapped = 0; + off_beg = off_end; + } + save_off = last_off; + save_bin = last_bin = c->bin; + save_tid = c->tid; + if (save_tid < 0) break; + } + if (bam_tell(fp) <= last_off) { + fprintf(pysamerr, "[bam_index_core] bug in BGZF/RAZF: %llx < %llx\n", + (unsigned long long)bam_tell(fp), (unsigned long long)last_off); + exit(1); + } + if (c->flag & BAM_FUNMAP) ++n_unmapped; + else ++n_mapped; + last_off = bam_tell(fp); + last_coor = b->core.pos; + } + if (save_tid >= 0) { + insert_offset(idx->index[save_tid], save_bin, save_off, bam_tell(fp)); + insert_offset(idx->index[save_tid], BAM_MAX_BIN, off_beg, bam_tell(fp)); + insert_offset(idx->index[save_tid], BAM_MAX_BIN, n_mapped, n_unmapped); + } + merge_chunks(idx); + fill_missing(idx); + if (ret >= 0) { + while ((ret = bam_read1(fp, b)) >= 0) { + ++n_no_coor; + if (c->tid >= 0 && n_no_coor) { + fprintf(pysamerr, "[bam_index_core] the alignment is not sorted: reads without coordinates prior to reads with coordinates.\n"); + exit(1); + } + } + } + if (ret < -1) fprintf(pysamerr, "[bam_index_core] truncated file? Continue anyway. (%d)\n", ret); + free(b->data); free(b); + idx->n_no_coor = n_no_coor; + return idx; +} + +void bam_index_destroy(bam_index_t *idx) +{ + khint_t k; + int i; + if (idx == 0) return; + for (i = 0; i < idx->n; ++i) { + khash_t(i) *index = idx->index[i]; + bam_lidx_t *index2 = idx->index2 + i; + for (k = kh_begin(index); k != kh_end(index); ++k) { + if (kh_exist(index, k)) + free(kh_value(index, k).list); + } + kh_destroy(i, index); + free(index2->offset); + } + free(idx->index); free(idx->index2); + free(idx); +} + +void bam_index_save(const bam_index_t *idx, FILE *fp) +{ + int32_t i, size; + khint_t k; + fwrite("BAI\1", 1, 4, fp); + if (bam_is_be) { + uint32_t x = idx->n; + fwrite(bam_swap_endian_4p(&x), 4, 1, fp); + } else fwrite(&idx->n, 4, 1, fp); + for (i = 0; i < idx->n; ++i) { + khash_t(i) *index = idx->index[i]; + bam_lidx_t *index2 = idx->index2 + i; + // write binning index + size = kh_size(index); + if (bam_is_be) { // big endian + uint32_t x = size; + fwrite(bam_swap_endian_4p(&x), 4, 1, fp); + } else fwrite(&size, 4, 1, fp); + for (k = kh_begin(index); k != kh_end(index); ++k) { + if (kh_exist(index, k)) { + bam_binlist_t *p = &kh_value(index, k); + if (bam_is_be) { // big endian + uint32_t x; + x = kh_key(index, k); fwrite(bam_swap_endian_4p(&x), 4, 1, fp); + x = p->n; fwrite(bam_swap_endian_4p(&x), 4, 1, fp); + for (x = 0; (int)x < p->n; ++x) { + bam_swap_endian_8p(&p->list[x].u); + bam_swap_endian_8p(&p->list[x].v); + } + fwrite(p->list, 16, p->n, fp); + for (x = 0; (int)x < p->n; ++x) { + bam_swap_endian_8p(&p->list[x].u); + bam_swap_endian_8p(&p->list[x].v); + } + } else { + fwrite(&kh_key(index, k), 4, 1, fp); + fwrite(&p->n, 4, 1, fp); + fwrite(p->list, 16, p->n, fp); + } + } + } + // write linear index (index2) + if (bam_is_be) { + int x = index2->n; + fwrite(bam_swap_endian_4p(&x), 4, 1, fp); + } else fwrite(&index2->n, 4, 1, fp); + if (bam_is_be) { // big endian + int x; + for (x = 0; (int)x < index2->n; ++x) + bam_swap_endian_8p(&index2->offset[x]); + fwrite(index2->offset, 8, index2->n, fp); + for (x = 0; (int)x < index2->n; ++x) + bam_swap_endian_8p(&index2->offset[x]); + } else fwrite(index2->offset, 8, index2->n, fp); + } + { // write the number of reads coor-less records. + uint64_t x = idx->n_no_coor; + if (bam_is_be) bam_swap_endian_8p(&x); + fwrite(&x, 8, 1, fp); + } + fflush(fp); +} + +static bam_index_t *bam_index_load_core(FILE *fp) +{ + int i; + char magic[4]; + bam_index_t *idx; + if (fp == 0) { + fprintf(pysamerr, "[bam_index_load_core] fail to load index.\n"); + return 0; + } + fread(magic, 1, 4, fp); + if (strncmp(magic, "BAI\1", 4)) { + fprintf(pysamerr, "[bam_index_load] wrong magic number.\n"); + fclose(fp); + return 0; + } + idx = (bam_index_t*)calloc(1, sizeof(bam_index_t)); + fread(&idx->n, 4, 1, fp); + if (bam_is_be) bam_swap_endian_4p(&idx->n); + idx->index = (khash_t(i)**)calloc(idx->n, sizeof(void*)); + idx->index2 = (bam_lidx_t*)calloc(idx->n, sizeof(bam_lidx_t)); + for (i = 0; i < idx->n; ++i) { + khash_t(i) *index; + bam_lidx_t *index2 = idx->index2 + i; + uint32_t key, size; + khint_t k; + int j, ret; + bam_binlist_t *p; + index = idx->index[i] = kh_init(i); + // load binning index + fread(&size, 4, 1, fp); + if (bam_is_be) bam_swap_endian_4p(&size); + for (j = 0; j < (int)size; ++j) { + fread(&key, 4, 1, fp); + if (bam_is_be) bam_swap_endian_4p(&key); + k = kh_put(i, index, key, &ret); + p = &kh_value(index, k); + fread(&p->n, 4, 1, fp); + if (bam_is_be) bam_swap_endian_4p(&p->n); + p->m = p->n; + p->list = (pair64_t*)malloc(p->m * 16); + fread(p->list, 16, p->n, fp); + if (bam_is_be) { + int x; + for (x = 0; x < p->n; ++x) { + bam_swap_endian_8p(&p->list[x].u); + bam_swap_endian_8p(&p->list[x].v); + } + } + } + // load linear index + fread(&index2->n, 4, 1, fp); + if (bam_is_be) bam_swap_endian_4p(&index2->n); + index2->m = index2->n; + index2->offset = (uint64_t*)calloc(index2->m, 8); + fread(index2->offset, index2->n, 8, fp); + if (bam_is_be) + for (j = 0; j < index2->n; ++j) bam_swap_endian_8p(&index2->offset[j]); + } + if (fread(&idx->n_no_coor, 8, 1, fp) == 0) idx->n_no_coor = 0; + if (bam_is_be) bam_swap_endian_8p(&idx->n_no_coor); + return idx; +} + +bam_index_t *bam_index_load_local(const char *_fn) +{ + FILE *fp; + char *fnidx, *fn; + + if (strstr(_fn, "ftp://") == _fn || strstr(_fn, "http://") == _fn) { + const char *p; + int l = strlen(_fn); + for (p = _fn + l - 1; p >= _fn; --p) + if (*p == '/') break; + fn = strdup(p + 1); + } else fn = strdup(_fn); + fnidx = (char*)calloc(strlen(fn) + 5, 1); + strcpy(fnidx, fn); strcat(fnidx, ".bai"); + fp = fopen(fnidx, "rb"); + if (fp == 0) { // try "{base}.bai" + char *s = strstr(fn, "bam"); + if (s == fn + strlen(fn) - 3) { + strcpy(fnidx, fn); + fnidx[strlen(fn)-1] = 'i'; + fp = fopen(fnidx, "rb"); + } + } + free(fnidx); free(fn); + if (fp) { + bam_index_t *idx = bam_index_load_core(fp); + fclose(fp); + return idx; + } else return 0; +} + +#ifdef _USE_KNETFILE +static void download_from_remote(const char *url) +{ + const int buf_size = 1 * 1024 * 1024; + char *fn; + FILE *fp; + uint8_t *buf; + knetFile *fp_remote; + int l; + if (strstr(url, "ftp://") != url && strstr(url, "http://") != url) return; + l = strlen(url); + for (fn = (char*)url + l - 1; fn >= url; --fn) + if (*fn == '/') break; + ++fn; // fn now points to the file name + fp_remote = knet_open(url, "r"); + if (fp_remote == 0) { + fprintf(pysamerr, "[download_from_remote] fail to open remote file.\n"); + return; + } + if ((fp = fopen(fn, "wb")) == 0) { + fprintf(pysamerr, "[download_from_remote] fail to create file in the working directory.\n"); + knet_close(fp_remote); + return; + } + buf = (uint8_t*)calloc(buf_size, 1); + while ((l = knet_read(fp_remote, buf, buf_size)) != 0) + fwrite(buf, 1, l, fp); + free(buf); + fclose(fp); + knet_close(fp_remote); +} +#else +static void download_from_remote(const char *url) +{ + return; +} +#endif + +bam_index_t *bam_index_load(const char *fn) +{ + bam_index_t *idx; + idx = bam_index_load_local(fn); + if (idx == 0 && (strstr(fn, "ftp://") == fn || strstr(fn, "http://") == fn)) { + char *fnidx = calloc(strlen(fn) + 5, 1); + strcat(strcpy(fnidx, fn), ".bai"); + fprintf(pysamerr, "[bam_index_load] attempting to download the remote index file.\n"); + download_from_remote(fnidx); + idx = bam_index_load_local(fn); + } + if (idx == 0) fprintf(pysamerr, "[bam_index_load] fail to load BAM index.\n"); + return idx; +} + +int bam_index_build2(const char *fn, const char *_fnidx) +{ + char *fnidx; + FILE *fpidx; + bamFile fp; + bam_index_t *idx; + if ((fp = bam_open(fn, "r")) == 0) { + fprintf(pysamerr, "[bam_index_build2] fail to open the BAM file.\n"); + return -1; + } + idx = bam_index_core(fp); + bam_close(fp); + if (_fnidx == 0) { + fnidx = (char*)calloc(strlen(fn) + 5, 1); + strcpy(fnidx, fn); strcat(fnidx, ".bai"); + } else fnidx = strdup(_fnidx); + fpidx = fopen(fnidx, "wb"); + if (fpidx == 0) { + fprintf(pysamerr, "[bam_index_build2] fail to create the index file.\n"); + free(fnidx); + return -1; + } + bam_index_save(idx, fpidx); + bam_index_destroy(idx); + fclose(fpidx); + free(fnidx); + return 0; +} + +int bam_index_build(const char *fn) +{ + return bam_index_build2(fn, 0); +} + +int bam_index(int argc, char *argv[]) +{ + if (argc < 2) { + fprintf(pysamerr, "Usage: samtools index [out.index]\n"); + return 1; + } + if (argc >= 3) bam_index_build2(argv[1], argv[2]); + else bam_index_build(argv[1]); + return 0; +} + +int bam_idxstats(int argc, char *argv[]) +{ + bam_index_t *idx; + bam_header_t *header; + bamFile fp; + int i; + if (argc < 2) { + fprintf(pysamerr, "Usage: samtools idxstats \n"); + return 1; + } + fp = bam_open(argv[1], "r"); + if (fp == 0) { fprintf(pysamerr, "[%s] fail to open BAM.\n", __func__); return 1; } + header = bam_header_read(fp); + bam_close(fp); + idx = bam_index_load(argv[1]); + if (idx == 0) { fprintf(pysamerr, "[%s] fail to load the index.\n", __func__); return 1; } + for (i = 0; i < idx->n; ++i) { + khint_t k; + khash_t(i) *h = idx->index[i]; + printf("%s\t%d", header->target_name[i], header->target_len[i]); + k = kh_get(i, h, BAM_MAX_BIN); + if (k != kh_end(h)) + printf("\t%llu\t%llu", (long long)kh_val(h, k).list[1].u, (long long)kh_val(h, k).list[1].v); + else printf("\t0\t0"); + putchar('\n'); + } + printf("*\t0\t0\t%llu\n", (long long)idx->n_no_coor); + bam_header_destroy(header); + bam_index_destroy(idx); + return 0; +} + +static inline int reg2bins(uint32_t beg, uint32_t end, uint16_t list[BAM_MAX_BIN]) +{ + int i = 0, k; + if (beg >= end) return 0; + if (end >= 1u<<29) end = 1u<<29; + --end; + list[i++] = 0; + for (k = 1 + (beg>>26); k <= 1 + (end>>26); ++k) list[i++] = k; + for (k = 9 + (beg>>23); k <= 9 + (end>>23); ++k) list[i++] = k; + for (k = 73 + (beg>>20); k <= 73 + (end>>20); ++k) list[i++] = k; + for (k = 585 + (beg>>17); k <= 585 + (end>>17); ++k) list[i++] = k; + for (k = 4681 + (beg>>14); k <= 4681 + (end>>14); ++k) list[i++] = k; + return i; +} + +static inline int is_overlap(uint32_t beg, uint32_t end, const bam1_t *b) +{ + uint32_t rbeg = b->core.pos; + uint32_t rend = b->core.n_cigar? bam_calend(&b->core, bam1_cigar(b)) : b->core.pos + 1; + return (rend > beg && rbeg < end); +} + +struct __bam_iter_t { + int from_first; // read from the first record; no random access + int tid, beg, end, n_off, i, finished; + uint64_t curr_off; + pair64_t *off; +}; + +// bam_fetch helper function retrieves +bam_iter_t bam_iter_query(const bam_index_t *idx, int tid, int beg, int end) +{ + uint16_t *bins; + int i, n_bins, n_off; + pair64_t *off; + khint_t k; + khash_t(i) *index; + uint64_t min_off; + bam_iter_t iter = 0; + + if (beg < 0) beg = 0; + if (end < beg) return 0; + // initialize iter + iter = calloc(1, sizeof(struct __bam_iter_t)); + iter->tid = tid, iter->beg = beg, iter->end = end; iter->i = -1; + // + bins = (uint16_t*)calloc(BAM_MAX_BIN, 2); + n_bins = reg2bins(beg, end, bins); + index = idx->index[tid]; + if (idx->index2[tid].n > 0) { + min_off = (beg>>BAM_LIDX_SHIFT >= idx->index2[tid].n)? idx->index2[tid].offset[idx->index2[tid].n-1] + : idx->index2[tid].offset[beg>>BAM_LIDX_SHIFT]; + if (min_off == 0) { // improvement for index files built by tabix prior to 0.1.4 + int n = beg>>BAM_LIDX_SHIFT; + if (n > idx->index2[tid].n) n = idx->index2[tid].n; + for (i = n - 1; i >= 0; --i) + if (idx->index2[tid].offset[i] != 0) break; + if (i >= 0) min_off = idx->index2[tid].offset[i]; + } + } else min_off = 0; // tabix 0.1.2 may produce such index files + for (i = n_off = 0; i < n_bins; ++i) { + if ((k = kh_get(i, index, bins[i])) != kh_end(index)) + n_off += kh_value(index, k).n; + } + if (n_off == 0) { + free(bins); return iter; + } + off = (pair64_t*)calloc(n_off, 16); + for (i = n_off = 0; i < n_bins; ++i) { + if ((k = kh_get(i, index, bins[i])) != kh_end(index)) { + int j; + bam_binlist_t *p = &kh_value(index, k); + for (j = 0; j < p->n; ++j) + if (p->list[j].v > min_off) off[n_off++] = p->list[j]; + } + } + free(bins); + if (n_off == 0) { + free(off); return iter; + } + { + bam1_t *b = (bam1_t*)calloc(1, sizeof(bam1_t)); + int l; + ks_introsort(off, n_off, off); + // resolve completely contained adjacent blocks + for (i = 1, l = 0; i < n_off; ++i) + if (off[l].v < off[i].v) + off[++l] = off[i]; + n_off = l + 1; + // resolve overlaps between adjacent blocks; this may happen due to the merge in indexing + for (i = 1; i < n_off; ++i) + if (off[i-1].v >= off[i].u) off[i-1].v = off[i].u; + { // merge adjacent blocks +#if defined(BAM_TRUE_OFFSET) || defined(BAM_VIRTUAL_OFFSET16) + for (i = 1, l = 0; i < n_off; ++i) { +#ifdef BAM_TRUE_OFFSET + if (off[l].v + BAM_MIN_CHUNK_GAP > off[i].u) off[l].v = off[i].v; +#else + if (off[l].v>>16 == off[i].u>>16) off[l].v = off[i].v; +#endif + else off[++l] = off[i]; + } + n_off = l + 1; +#endif + } + bam_destroy1(b); + } + iter->n_off = n_off; iter->off = off; + return iter; +} + +pair64_t *get_chunk_coordinates(const bam_index_t *idx, int tid, int beg, int end, int *cnt_off) +{ // for pysam compatibility + bam_iter_t iter; + pair64_t *off; + iter = bam_iter_query(idx, tid, beg, end); + off = iter->off; *cnt_off = iter->n_off; + free(iter); + return off; +} + +void bam_iter_destroy(bam_iter_t iter) +{ + if (iter) { free(iter->off); free(iter); } +} + +int bam_iter_read(bamFile fp, bam_iter_t iter, bam1_t *b) +{ + int ret; + if (iter && iter->finished) return -1; + if (iter == 0 || iter->from_first) { + ret = bam_read1(fp, b); + if (ret < 0 && iter) iter->finished = 1; + return ret; + } + if (iter->off == 0) return -1; + for (;;) { + if (iter->curr_off == 0 || iter->curr_off >= iter->off[iter->i].v) { // then jump to the next chunk + if (iter->i == iter->n_off - 1) { ret = -1; break; } // no more chunks + if (iter->i >= 0) assert(iter->curr_off == iter->off[iter->i].v); // otherwise bug + if (iter->i < 0 || iter->off[iter->i].v != iter->off[iter->i+1].u) { // not adjacent chunks; then seek + bam_seek(fp, iter->off[iter->i+1].u, SEEK_SET); + iter->curr_off = bam_tell(fp); + } + ++iter->i; + } + if ((ret = bam_read1(fp, b)) >= 0) { + iter->curr_off = bam_tell(fp); + if (b->core.tid != iter->tid || b->core.pos >= iter->end) { // no need to proceed + ret = bam_validate1(NULL, b)? -1 : -5; // determine whether end of region or error + break; + } + else if (is_overlap(iter->beg, iter->end, b)) return ret; + } else break; // end of file or error + } + iter->finished = 1; + return ret; +} + +int bam_fetch(bamFile fp, const bam_index_t *idx, int tid, int beg, int end, void *data, bam_fetch_f func) +{ + int ret; + bam_iter_t iter; + bam1_t *b; + b = bam_init1(); + iter = bam_iter_query(idx, tid, beg, end); + while ((ret = bam_iter_read(fp, iter, b)) >= 0) func(b, data); + bam_iter_destroy(iter); + bam_destroy1(b); + return (ret == -1)? 0 : ret; +}