X-Git-Url: http://woldlab.caltech.edu/gitweb/?p=pysam.git;a=blobdiff_plain;f=samtools%2Fbam_index.c;fp=samtools%2Fbam_index.c;h=0000000000000000000000000000000000000000;hp=4152f2022f3178ef4fd0ee6b6001effae8f2ce3c;hb=d02fe5283ed7a93a2f76a5d6dc6e37b40c11b9b1;hpb=d828f9c9aa78e3d1687265b52de841f3f3852089 diff --git a/samtools/bam_index.c b/samtools/bam_index.c deleted file mode 100644 index 4152f20..0000000 --- a/samtools/bam_index.c +++ /dev/null @@ -1,696 +0,0 @@ -#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(stderr, "[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(stderr, "[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, off_end); - 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 (ret < -1) fprintf(stderr, "[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(stderr, "[bam_index_load_core] fail to load index.\n"); - return 0; - } - fread(magic, 1, 4, fp); - if (strncmp(magic, "BAI\1", 4)) { - fprintf(stderr, "[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(stderr, "[download_from_remote] fail to open remote file.\n"); - return; - } - if ((fp = fopen(fn, "wb")) == 0) { - fprintf(stderr, "[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(stderr, "[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(stderr, "[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(stderr, "[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(stderr, "[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(stderr, "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(stderr, "Usage: samtools idxstats \n"); - return 1; - } - fp = bam_open(argv[1], "r"); - if (fp == 0) { fprintf(stderr, "[%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(stderr, "[%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); - { - 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) -{ - if (iter->finished) return -1; - if (iter->from_first) { - int ret = bam_read1(fp, b); - if (ret < 0) iter->finished = 1; - return ret; - } - if (iter->off == 0) return -1; - for (;;) { - int ret; - 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) 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) break; // no need to proceed - else if (is_overlap(iter->beg, iter->end, b)) return ret; - } else break; // end of file - } - iter->finished = 1; - return -1; -} - -int bam_fetch(bamFile fp, const bam_index_t *idx, int tid, int beg, int end, void *data, bam_fetch_f func) -{ - bam_iter_t iter; - bam1_t *b; - b = bam_init1(); - iter = bam_iter_query(idx, tid, beg, end); - while (bam_iter_read(fp, iter, b) >= 0) func(b, data); - bam_destroy1(b); - return 0; -}