--- /dev/null
+/* The MIT License
+
+ Copyright (c) 2008 Broad Institute / Massachusetts Institute of Technology
+ 2011 Attractive Chaos <attractor@live.co.uk>
+
+ Permission is hereby granted, free of charge, to any person obtaining a copy
+ of this software and associated documentation files (the "Software"), to deal
+ in the Software without restriction, including without limitation the rights
+ to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ copies of the Software, and to permit persons to whom the Software is
+ furnished to do so, subject to the following conditions:
+
+ The above copyright notice and this permission notice shall be included in
+ all copies or substantial portions of the Software.
+
+ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ THE SOFTWARE.
+*/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <assert.h>
+#include <sys/types.h>
+#include "bgzf.h"
+
+#ifdef _USE_KNETFILE
+#include "knetfile.h"
+typedef knetFile *_bgzf_file_t;
+#define _bgzf_open(fn, mode) knet_open(fn, mode)
+#define _bgzf_dopen(fp, mode) knet_dopen(fp, mode)
+#define _bgzf_close(fp) knet_close(fp)
+#define _bgzf_fileno(fp) ((fp)->fd)
+#define _bgzf_tell(fp) knet_tell(fp)
+#define _bgzf_seek(fp, offset, whence) knet_seek(fp, offset, whence)
+#define _bgzf_read(fp, buf, len) knet_read(fp, buf, len)
+#define _bgzf_write(fp, buf, len) knet_write(fp, buf, len)
+#else // ~defined(_USE_KNETFILE)
+#if defined(_WIN32) || defined(_MSC_VER)
+#define ftello(fp) ftell(fp)
+#define fseeko(fp, offset, whence) fseek(fp, offset, whence)
+#else // ~defined(_WIN32)
+extern off_t ftello(FILE *stream);
+extern int fseeko(FILE *stream, off_t offset, int whence);
+#endif // ~defined(_WIN32)
+typedef FILE *_bgzf_file_t;
+#define _bgzf_open(fn, mode) fopen(fn, mode)
+#define _bgzf_dopen(fp, mode) fdopen(fp, mode)
+#define _bgzf_close(fp) fclose(fp)
+#define _bgzf_fileno(fp) fileno(fp)
+#define _bgzf_tell(fp) ftello(fp)
+#define _bgzf_seek(fp, offset, whence) fseeko(fp, offset, whence)
+#define _bgzf_read(fp, buf, len) fread(buf, 1, len, fp)
+#define _bgzf_write(fp, buf, len) fwrite(buf, 1, len, fp)
+#endif // ~define(_USE_KNETFILE)
+
+#define BLOCK_HEADER_LENGTH 18
+#define BLOCK_FOOTER_LENGTH 8
+
+/* BGZF/GZIP header (speciallized from RFC 1952; little endian):
+ +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
+ | 31|139| 8| 4| 0| 0|255| 6| 66| 67| 2|BLK_LEN|
+ +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
+*/
+static const uint8_t g_magic[19] = "\037\213\010\4\0\0\0\0\0\377\6\0\102\103\2\0\0\0";
+
+#ifdef BGZF_CACHE
+typedef struct {
+ int size;
+ uint8_t *block;
+ int64_t end_offset;
+} cache_t;
+#include "khash.h"
+KHASH_MAP_INIT_INT64(cache, cache_t)
+#endif
+
+static inline void packInt16(uint8_t *buffer, uint16_t value)
+{
+ buffer[0] = value;
+ buffer[1] = value >> 8;
+}
+
+static inline int unpackInt16(const uint8_t *buffer)
+{
+ return buffer[0] | buffer[1] << 8;
+}
+
+static inline void packInt32(uint8_t *buffer, uint32_t value)
+{
+ buffer[0] = value;
+ buffer[1] = value >> 8;
+ buffer[2] = value >> 16;
+ buffer[3] = value >> 24;
+}
+
+static BGZF *bgzf_read_init()
+{
+ BGZF *fp;
+ fp = calloc(1, sizeof(BGZF));
+ fp->open_mode = 'r';
+ fp->uncompressed_block = malloc(BGZF_BLOCK_SIZE);
+ fp->compressed_block = malloc(BGZF_BLOCK_SIZE);
+#ifdef BGZF_CACHE
+ fp->cache = kh_init(cache);
+#endif
+ return fp;
+}
+
+static BGZF *bgzf_write_init(int compress_level) // compress_level==-1 for the default level
+{
+ BGZF *fp;
+ fp = calloc(1, sizeof(BGZF));
+ fp->open_mode = 'w';
+ fp->uncompressed_block = malloc(BGZF_BLOCK_SIZE);
+ fp->compressed_block = malloc(BGZF_BLOCK_SIZE);
+ fp->compress_level = compress_level < 0? Z_DEFAULT_COMPRESSION : compress_level; // Z_DEFAULT_COMPRESSION==-1
+ if (fp->compress_level > 9) fp->compress_level = Z_DEFAULT_COMPRESSION;
+ return fp;
+}
+// get the compress level from the mode string
+static int mode2level(const char *__restrict mode)
+{
+ int i, compress_level = -1;
+ for (i = 0; mode[i]; ++i)
+ if (mode[i] >= '0' && mode[i] <= '9') break;
+ if (mode[i]) compress_level = (int)mode[i] - '0';
+ if (strchr(mode, 'u')) compress_level = 0;
+ return compress_level;
+}
+
+BGZF *bgzf_open(const char *path, const char *mode)
+{
+ BGZF *fp = 0;
+ if (strchr(mode, 'r') || strchr(mode, 'R')) {
+ _bgzf_file_t fpr;
+ if ((fpr = _bgzf_open(path, "r")) == 0) return 0;
+ fp = bgzf_read_init();
+ fp->fp = fpr;
+ } else if (strchr(mode, 'w') || strchr(mode, 'W')) {
+ FILE *fpw;
+ if ((fpw = fopen(path, "w")) == 0) return 0;
+ fp = bgzf_write_init(mode2level(mode));
+ fp->fp = fpw;
+ }
+ return fp;
+}
+
+BGZF *bgzf_dopen(int fd, const char *mode)
+{
+ BGZF *fp = 0;
+ if (strchr(mode, 'r') || strchr(mode, 'R')) {
+ _bgzf_file_t fpr;
+ if ((fpr = _bgzf_dopen(fd, "r")) == 0) return 0;
+ fp = bgzf_read_init();
+ fp->fp = fpr;
+ } else if (strchr(mode, 'w') || strchr(mode, 'W')) {
+ FILE *fpw;
+ if ((fpw = fdopen(fd, "w")) == 0) return 0;
+ fp = bgzf_write_init(mode2level(mode));
+ fp->fp = fpw;
+ }
+ return fp;
+}
+
+// Deflate the block in fp->uncompressed_block into fp->compressed_block. Also adds an extra field that stores the compressed block length.
+static int deflate_block(BGZF *fp, int block_length)
+{
+ uint8_t *buffer = fp->compressed_block;
+ int buffer_size = BGZF_BLOCK_SIZE;
+ int input_length = block_length;
+ int compressed_length = 0;
+ int remaining;
+ uint32_t crc;
+
+ assert(block_length <= BGZF_BLOCK_SIZE); // guaranteed by the caller
+ memcpy(buffer, g_magic, BLOCK_HEADER_LENGTH); // the last two bytes are a place holder for the length of the block
+ while (1) { // loop to retry for blocks that do not compress enough
+ int status;
+ z_stream zs;
+ zs.zalloc = NULL;
+ zs.zfree = NULL;
+ zs.next_in = fp->uncompressed_block;
+ zs.avail_in = input_length;
+ zs.next_out = (void*)&buffer[BLOCK_HEADER_LENGTH];
+ zs.avail_out = buffer_size - BLOCK_HEADER_LENGTH - BLOCK_FOOTER_LENGTH;
+ status = deflateInit2(&zs, fp->compress_level, Z_DEFLATED, -15, 8, Z_DEFAULT_STRATEGY); // -15 to disable zlib header/footer
+ if (status != Z_OK) {
+ fp->errcode |= BGZF_ERR_ZLIB;
+ return -1;
+ }
+ status = deflate(&zs, Z_FINISH);
+ if (status != Z_STREAM_END) { // not compressed enough
+ deflateEnd(&zs); // reset the stream
+ if (status == Z_OK) { // reduce the size and recompress
+ input_length -= 1024;
+ assert(input_length > 0); // logically, this should not happen
+ continue;
+ }
+ fp->errcode |= BGZF_ERR_ZLIB;
+ return -1;
+ }
+ if (deflateEnd(&zs) != Z_OK) {
+ fp->errcode |= BGZF_ERR_ZLIB;
+ return -1;
+ }
+ compressed_length = zs.total_out;
+ compressed_length += BLOCK_HEADER_LENGTH + BLOCK_FOOTER_LENGTH;
+ assert(compressed_length <= BGZF_BLOCK_SIZE);
+ break;
+ }
+
+ assert(compressed_length > 0);
+ packInt16((uint8_t*)&buffer[16], compressed_length - 1); // write the compressed_length; -1 to fit 2 bytes
+ crc = crc32(0L, NULL, 0L);
+ crc = crc32(crc, fp->uncompressed_block, input_length);
+ packInt32((uint8_t*)&buffer[compressed_length-8], crc);
+ packInt32((uint8_t*)&buffer[compressed_length-4], input_length);
+
+ remaining = block_length - input_length;
+ if (remaining > 0) {
+ assert(remaining <= input_length);
+ memcpy(fp->uncompressed_block, fp->uncompressed_block + input_length, remaining);
+ }
+ fp->block_offset = remaining;
+ return compressed_length;
+}
+
+// Inflate the block in fp->compressed_block into fp->uncompressed_block
+static int inflate_block(BGZF* fp, int block_length)
+{
+ z_stream zs;
+ zs.zalloc = NULL;
+ zs.zfree = NULL;
+ zs.next_in = fp->compressed_block + 18;
+ zs.avail_in = block_length - 16;
+ zs.next_out = fp->uncompressed_block;
+ zs.avail_out = BGZF_BLOCK_SIZE;
+
+ if (inflateInit2(&zs, -15) != Z_OK) {
+ fp->errcode |= BGZF_ERR_ZLIB;
+ return -1;
+ }
+ if (inflate(&zs, Z_FINISH) != Z_STREAM_END) {
+ inflateEnd(&zs);
+ fp->errcode |= BGZF_ERR_ZLIB;
+ return -1;
+ }
+ if (inflateEnd(&zs) != Z_OK) {
+ fp->errcode |= BGZF_ERR_ZLIB;
+ return -1;
+ }
+ return zs.total_out;
+}
+
+static int check_header(const uint8_t *header)
+{
+ return (header[0] == 31 && header[1] == 139 && header[2] == 8 && (header[3] & 4) != 0
+ && unpackInt16((uint8_t*)&header[10]) == 6
+ && header[12] == 'B' && header[13] == 'C'
+ && unpackInt16((uint8_t*)&header[14]) == 2);
+}
+
+#ifdef BGZF_CACHE
+static void free_cache(BGZF *fp)
+{
+ khint_t k;
+ khash_t(cache) *h = (khash_t(cache)*)fp->cache;
+ if (fp->open_mode != 'r') return;
+ for (k = kh_begin(h); k < kh_end(h); ++k)
+ if (kh_exist(h, k)) free(kh_val(h, k).block);
+ kh_destroy(cache, h);
+}
+
+static int load_block_from_cache(BGZF *fp, int64_t block_address)
+{
+ khint_t k;
+ cache_t *p;
+ khash_t(cache) *h = (khash_t(cache)*)fp->cache;
+ k = kh_get(cache, h, block_address);
+ if (k == kh_end(h)) return 0;
+ p = &kh_val(h, k);
+ if (fp->block_length != 0) fp->block_offset = 0;
+ fp->block_address = block_address;
+ fp->block_length = p->size;
+ memcpy(fp->uncompressed_block, p->block, BGZF_BLOCK_SIZE);
+ _bgzf_seek((_bgzf_file_t)fp->fp, p->end_offset, SEEK_SET);
+ return p->size;
+}
+
+static void cache_block(BGZF *fp, int size)
+{
+ int ret;
+ khint_t k;
+ cache_t *p;
+ khash_t(cache) *h = (khash_t(cache)*)fp->cache;
+ if (BGZF_BLOCK_SIZE >= fp->cache_size) return;
+ if ((kh_size(h) + 1) * BGZF_BLOCK_SIZE > fp->cache_size) {
+ /* A better way would be to remove the oldest block in the
+ * cache, but here we remove a random one for simplicity. This
+ * should not have a big impact on performance. */
+ for (k = kh_begin(h); k < kh_end(h); ++k)
+ if (kh_exist(h, k)) break;
+ if (k < kh_end(h)) {
+ free(kh_val(h, k).block);
+ kh_del(cache, h, k);
+ }
+ }
+ k = kh_put(cache, h, fp->block_address, &ret);
+ if (ret == 0) return; // if this happens, a bug!
+ p = &kh_val(h, k);
+ p->size = fp->block_length;
+ p->end_offset = fp->block_address + size;
+ p->block = malloc(BGZF_BLOCK_SIZE);
+ memcpy(kh_val(h, k).block, fp->uncompressed_block, BGZF_BLOCK_SIZE);
+}
+#else
+static void free_cache(BGZF *fp) {}
+static int load_block_from_cache(BGZF *fp, int64_t block_address) {return 0;}
+static void cache_block(BGZF *fp, int size) {}
+#endif
+
+static int bgzf_read_block(BGZF *fp)
+{
+ uint8_t header[BLOCK_HEADER_LENGTH], *compressed_block;
+ int count, size = 0, block_length, remaining;
+ int64_t block_address;
+ block_address = _bgzf_tell((_bgzf_file_t)fp->fp);
+ if (load_block_from_cache(fp, block_address)) return 0;
+ count = _bgzf_read(fp->fp, header, sizeof(header));
+ if (count == 0) { // no data read
+ fp->block_length = 0;
+ return 0;
+ }
+ if (count != sizeof(header) || !check_header(header)) {
+ fp->errcode |= BGZF_ERR_HEADER;
+ return -1;
+ }
+ size = count;
+ block_length = unpackInt16((uint8_t*)&header[16]) + 1; // +1 because when writing this number, we used "-1"
+ compressed_block = (uint8_t*)fp->compressed_block;
+ memcpy(compressed_block, header, BLOCK_HEADER_LENGTH);
+ remaining = block_length - BLOCK_HEADER_LENGTH;
+ count = _bgzf_read(fp->fp, &compressed_block[BLOCK_HEADER_LENGTH], remaining);
+ if (count != remaining) {
+ fp->errcode |= BGZF_ERR_IO;
+ return -1;
+ }
+ size += count;
+ if (inflate_block(fp, block_length) < 0) return -1;
+ if (fp->block_length != 0) fp->block_offset = 0; // Do not reset offset if this read follows a seek.
+ fp->block_address = block_address;
+ fp->block_length = count;
+ cache_block(fp, size);
+ return 0;
+}
+
+ssize_t bgzf_read(BGZF *fp, void *data, ssize_t length)
+{
+ ssize_t bytes_read = 0;
+ uint8_t *output = data;
+ if (length <= 0) return 0;
+ assert(fp->open_mode == 'r');
+ while (bytes_read < length) {
+ int copy_length, available = fp->block_length - fp->block_offset;
+ uint8_t *buffer;
+ if (available <= 0) {
+ if (bgzf_read_block(fp) != 0) return -1;
+ available = fp->block_length - fp->block_offset;
+ if (available <= 0) break;
+ }
+ copy_length = length - bytes_read < available? length - bytes_read : available;
+ buffer = fp->uncompressed_block;
+ memcpy(output, buffer + fp->block_offset, copy_length);
+ fp->block_offset += copy_length;
+ output += copy_length;
+ bytes_read += copy_length;
+ }
+ if (fp->block_offset == fp->block_length) {
+ fp->block_address = _bgzf_tell((_bgzf_file_t)fp->fp);
+ fp->block_offset = fp->block_length = 0;
+ }
+ return bytes_read;
+}
+
+int bgzf_flush(BGZF *fp)
+{
+ assert(fp->open_mode == 'w');
+ while (fp->block_offset > 0) {
+ int block_length;
+ block_length = deflate_block(fp, fp->block_offset);
+ if (block_length < 0) return -1;
+ if (fwrite(fp->compressed_block, 1, block_length, fp->fp) != block_length) {
+ fp->errcode |= BGZF_ERR_IO; // possibly truncated file
+ return -1;
+ }
+ fp->block_address += block_length;
+ }
+ return 0;
+}
+
+int bgzf_flush_try(BGZF *fp, ssize_t size)
+{
+ if (fp->block_offset + size > BGZF_BLOCK_SIZE)
+ return bgzf_flush(fp);
+ return -1;
+}
+
+ssize_t bgzf_write(BGZF *fp, const void *data, ssize_t length)
+{
+ const uint8_t *input = data;
+ int block_length = BGZF_BLOCK_SIZE, bytes_written;
+ assert(fp->open_mode == 'w');
+ input = data;
+ bytes_written = 0;
+ while (bytes_written < length) {
+ uint8_t* buffer = fp->uncompressed_block;
+ int copy_length = block_length - fp->block_offset < length - bytes_written? block_length - fp->block_offset : length - bytes_written;
+ memcpy(buffer + fp->block_offset, input, copy_length);
+ fp->block_offset += copy_length;
+ input += copy_length;
+ bytes_written += copy_length;
+ if (fp->block_offset == block_length && bgzf_flush(fp)) break;
+ }
+ return bytes_written;
+}
+
+int bgzf_close(BGZF* fp)
+{
+ int ret, count, block_length;
+ if (fp == 0) return -1;
+ if (fp->open_mode == 'w') {
+ if (bgzf_flush(fp) != 0) return -1;
+ block_length = deflate_block(fp, 0); // write an empty block
+ count = fwrite(fp->compressed_block, 1, block_length, fp->fp);
+ if (fflush(fp->fp) != 0) {
+ fp->errcode |= BGZF_ERR_IO;
+ return -1;
+ }
+ }
+ ret = fp->open_mode == 'w'? fclose(fp->fp) : _bgzf_close(fp->fp);
+ if (ret != 0) return -1;
+ free(fp->uncompressed_block);
+ free(fp->compressed_block);
+ free_cache(fp);
+ free(fp);
+ return 0;
+}
+
+void bgzf_set_cache_size(BGZF *fp, int cache_size)
+{
+ if (fp) fp->cache_size = cache_size;
+}
+
+int bgzf_check_EOF(BGZF *fp)
+{
+ static uint8_t magic[28] = "\037\213\010\4\0\0\0\0\0\377\6\0\102\103\2\0\033\0\3\0\0\0\0\0\0\0\0\0";
+ uint8_t buf[28];
+ off_t offset;
+ offset = _bgzf_tell((_bgzf_file_t)fp->fp);
+ if (_bgzf_seek(fp->fp, -28, SEEK_END) < 0) return 0;
+ _bgzf_read(fp->fp, buf, 28);
+ _bgzf_seek(fp->fp, offset, SEEK_SET);
+ return (memcmp(magic, buf, 28) == 0)? 1 : 0;
+}
+
+int64_t bgzf_seek(BGZF* fp, int64_t pos, int where)
+{
+ int block_offset;
+ int64_t block_address;
+
+ if (fp->open_mode != 'r' || where != SEEK_SET) {
+ fp->errcode |= BGZF_ERR_MISUSE;
+ return -1;
+ }
+ block_offset = pos & 0xFFFF;
+ block_address = pos >> 16;
+ if (_bgzf_seek(fp->fp, block_address, SEEK_SET) < 0) {
+ fp->errcode |= BGZF_ERR_IO;
+ return -1;
+ }
+ fp->block_length = 0; // indicates current block has not been loaded
+ fp->block_address = block_address;
+ fp->block_offset = block_offset;
+ return 0;
+}
+
+int bgzf_is_bgzf(const char *fn)
+{
+ uint8_t buf[16];
+ int n;
+ _bgzf_file_t fp;
+ if ((fp = _bgzf_open(fn, "r")) == 0) return 0;
+ n = _bgzf_read(fp, buf, 16);
+ _bgzf_close(fp);
+ if (n != 16) return 0;
+ return memcmp(g_magic, buf, 16) == 0? 1 : 0;
+}
+
+int bgzf_getc(BGZF *fp)
+{
+ int c;
+ if (fp->block_offset >= fp->block_length) {
+ if (bgzf_read_block(fp) != 0) return -2; /* error */
+ if (fp->block_length == 0) return -1; /* end-of-file */
+ }
+ c = ((unsigned char*)fp->uncompressed_block)[fp->block_offset++];
+ if (fp->block_offset == fp->block_length) {
+ fp->block_address = _bgzf_tell((_bgzf_file_t)fp->fp);
+ fp->block_offset = 0;
+ fp->block_length = 0;
+ }
+ return c;
+}
+
+#ifndef kroundup32
+#define kroundup32(x) (--(x), (x)|=(x)>>1, (x)|=(x)>>2, (x)|=(x)>>4, (x)|=(x)>>8, (x)|=(x)>>16, ++(x))
+#endif
+
+int bgzf_getline(BGZF *fp, int delim, kstring_t *str)
+{
+ int l, state = 0;
+ unsigned char *buf = (unsigned char*)fp->uncompressed_block;
+ str->l = 0;
+ do {
+ if (fp->block_offset >= fp->block_length) {
+ if (bgzf_read_block(fp) != 0) { state = -2; break; }
+ if (fp->block_length == 0) { state = -1; break; }
+ }
+ for (l = fp->block_offset; l < fp->block_length && buf[l] != delim; ++l);
+ if (l < fp->block_length) state = 1;
+ l -= fp->block_offset;
+ if (str->l + l + 1 >= str->m) {
+ str->m = str->l + l + 2;
+ kroundup32(str->m);
+ str->s = (char*)realloc(str->s, str->m);
+ }
+ memcpy(str->s + str->l, buf + fp->block_offset, l);
+ str->l += l;
+ fp->block_offset += l + 1;
+ if (fp->block_offset >= fp->block_length) {
+ fp->block_address = _bgzf_tell((_bgzf_file_t)fp->fp);
+ fp->block_offset = 0;
+ fp->block_length = 0;
+ }
+ } while (state == 0);
+ if (str->l == 0 && state < 0) return state;
+ str->s[str->l] = 0;
+ return str->l;
+}
--- /dev/null
+/* The MIT License
+
+ Copyright (c) 2008 Broad Institute / Massachusetts Institute of Technology
+ 2011 Attractive Chaos <attractor@live.co.uk>
+
+ Permission is hereby granted, free of charge, to any person obtaining a copy
+ of this software and associated documentation files (the "Software"), to deal
+ in the Software without restriction, including without limitation the rights
+ to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ copies of the Software, and to permit persons to whom the Software is
+ furnished to do so, subject to the following conditions:
+
+ The above copyright notice and this permission notice shall be included in
+ all copies or substantial portions of the Software.
+
+ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ THE SOFTWARE.
+*/
+
+/* The BGZF library was originally written by Bob Handsaker from the Broad
+ * Institute. It was later improved by the SAMtools developers. */
+
+#ifndef __BGZF_H
+#define __BGZF_H
+
+#include <stdint.h>
+#include <stdio.h>
+#include <zlib.h>
+
+#define BGZF_BLOCK_SIZE 0x10000 // 64k
+
+#define BGZF_ERR_ZLIB 1
+#define BGZF_ERR_HEADER 2
+#define BGZF_ERR_IO 4
+#define BGZF_ERR_MISUSE 8
+
+typedef struct {
+ int open_mode:8, compress_level:8, errcode:16;
+ int cache_size;
+ int block_length, block_offset;
+ int64_t block_address;
+ void *uncompressed_block, *compressed_block;
+ void *cache; // a pointer to a hash table
+ void *fp; // actual file handler; FILE* on writing; FILE* or knetFile* on reading
+} BGZF;
+
+#ifndef KSTRING_T
+#define KSTRING_T kstring_t
+typedef struct __kstring_t {
+ size_t l, m;
+ char *s;
+} kstring_t;
+#endif
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+ /******************
+ * Basic routines *
+ ******************/
+
+ /**
+ * Open an existing file descriptor for reading or writing.
+ *
+ * @param fd file descriptor
+ * @param mode mode matching /[rwu0-9]+/: 'r' for reading, 'w' for writing and a digit specifies
+ * the zlib compression level; if both 'r' and 'w' are present, 'w' is ignored.
+ * @return BGZF file handler; 0 on error
+ */
+ BGZF* bgzf_dopen(int fd, const char *mode);
+
+ /**
+ * Open the specified file for reading or writing.
+ */
+ BGZF* bgzf_open(const char* path, const char *mode);
+
+ /**
+ * Close the BGZF and free all associated resources.
+ *
+ * @param fp BGZF file handler
+ * @return 0 on success and -1 on error
+ */
+ int bgzf_close(BGZF *fp);
+
+ /**
+ * Read up to _length_ bytes from the file storing into _data_.
+ *
+ * @param fp BGZF file handler
+ * @param data data array to read into
+ * @param length size of data to read
+ * @return number of bytes actually read; 0 on end-of-file and -1 on error
+ */
+ ssize_t bgzf_read(BGZF *fp, void *data, ssize_t length);
+
+ /**
+ * Write _length_ bytes from _data_ to the file.
+ *
+ * @param fp BGZF file handler
+ * @param data data array to write
+ * @param length size of data to write
+ * @return number of bytes actually written; -1 on error
+ */
+ ssize_t bgzf_write(BGZF *fp, const void *data, ssize_t length);
+
+ /**
+ * Write the data in the buffer to the file.
+ */
+ int bgzf_flush(BGZF *fp);
+
+ /**
+ * Return a virtual file pointer to the current location in the file.
+ * No interpetation of the value should be made, other than a subsequent
+ * call to bgzf_seek can be used to position the file at the same point.
+ * Return value is non-negative on success.
+ */
+ #define bgzf_tell(fp) ((fp->block_address << 16) | (fp->block_offset & 0xFFFF))
+
+ /**
+ * Set the file to read from the location specified by _pos_.
+ *
+ * @param fp BGZF file handler
+ * @param pos virtual file offset returned by bgzf_tell()
+ * @param whence must be SEEK_SET
+ * @return 0 on success and -1 on error
+ */
+ int64_t bgzf_seek(BGZF *fp, int64_t pos, int whence);
+
+ /**
+ * Check if the BGZF end-of-file (EOF) marker is present
+ *
+ * @param fp BGZF file handler opened for reading
+ * @return 1 if EOF is present; 0 if not or on I/O error
+ */
+ int bgzf_check_EOF(BGZF *fp);
+
+ /**
+ * Check if a file is in the BGZF format
+ *
+ * @param fn file name
+ * @return 1 if _fn_ is BGZF; 0 if not or on I/O error
+ */
+ int bgzf_is_bgzf(const char *fn);
+
+ /*********************
+ * Advanced routines *
+ *********************/
+
+ /**
+ * Set the cache size. Only effective when compiled with -DBGZF_CACHE.
+ *
+ * @param fp BGZF file handler
+ * @param size size of cache in bytes; 0 to disable caching (default)
+ */
+ void bgzf_set_cache_size(BGZF *fp, int size);
+
+ /**
+ * Flush the file if the remaining buffer size is smaller than _size_
+ */
+ int bgzf_flush_try(BGZF *fp, ssize_t size);
+
+ /**
+ * Read one byte from a BGZF file. It is faster than bgzf_read()
+ * @param fp BGZF file handler
+ * @return byte read; -1 on end-of-file or error
+ */
+ int bgzf_getc(BGZF *fp);
+
+ /**
+ * Read one line from a BGZF file. It is faster than bgzf_getc()
+ *
+ * @param fp BGZF file handler
+ * @param delim delimitor
+ * @param str string to write to; must be initialized
+ * @return length of the string; 0 on end-of-file; negative on error
+ */
+ int bgzf_getline(BGZF *fp, int delim, kstring_t *str);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
projects / klib.git / commitdiff