razf.c

/*
 * RAZF : Random Access compressed(Z) File
 * Version: 1.0
 * Release Date: 2008-10-27
 *
 * Copyright 2008, Jue Ruan <ruanjue@gmail.com>, Heng Li <lh3@sanger.ac.uk>
 *
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#ifndef _NO_RAZF

#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "razf.h"

#ifdef _MSC_VER
#define inline __inline
#endif

#if ZLIB_VERNUM < 0x1221
struct _gz_header_s
{
    int     text;
    uLong   time;
    int     xflags;
    int     os;
    Bytef   *extra;
    uInt    extra_len;
    uInt    extra_max;
    Bytef   *name;
    uInt    name_max;
    Bytef   *comment;
    uInt    comm_max;
    int     hcrc;
    int     done;
};
#warning "zlib < 1.2.2.1; RAZF writing is disabled."
#endif

#define DEF_MEM_LEVEL 8

/* gzip flag byte */
#define ASCII_FLAG   0x01 /* bit 0 set: file probably ascii text */
#define HEAD_CRC     0x02 /* bit 1 set: header CRC present */
#define EXTRA_FIELD  0x04 /* bit 2 set: extra field present */
#define ORIG_NAME    0x08 /* bit 3 set: original file name present */
#define COMMENT      0x10 /* bit 4 set: file comment present */
#define RESERVED     0xE0 /* bits 5..7: reserved */

static inline uint32_t byte_swap_4(uint32_t v)
{
    v = ((v & 0x0000FFFFU) << 16) | (v >> 16);
    return ((v & 0x00FF00FFU) << 8) | ((v & 0xFF00FF00U) >> 8);
}

static inline uint64_t byte_swap_8(uint64_t v)
{
    v = ((v & 0x00000000FFFFFFFFULL) << 32) | (v >> 32);
    v = ((v & 0x0000FFFF0000FFFFULL) << 16) | ((v & 0xFFFF0000FFFF0000ULL) >> 16);
    return ((v & 0x00FF00FF00FF00FFULL) << 8) | ((v & 0xFF00FF00FF00FF00ULL) >> 8);
}

static inline int is_big_endian(void)
{
    int x = 0x01;
    char *c = (char*)&x;
    return (c[0] != 0x01);
}

#ifndef _RZ_READONLY
static void add_zindex(RAZF *rz, int64_t in, int64_t out)
{
    if (rz->index->size == rz->index->cap)
    {
        rz->index->cap = rz->index->cap * 1.5 + 2;
        rz->index->cell_offsets = (uint32_t*)realloc(rz->index->cell_offsets, sizeof(uint32_t) * rz->index->cap);
        rz->index->bin_offsets  = (int64_t*)realloc(rz->index->bin_offsets, sizeof(int64_t) * (rz->index->cap/RZ_BIN_SIZE + 1));
    }

    if (rz->index->size % RZ_BIN_SIZE == 0)
        rz->index->bin_offsets[rz->index->size / RZ_BIN_SIZE] = out;
    rz->index->cell_offsets[rz->index->size] = out - rz->index->bin_offsets[rz->index->size / RZ_BIN_SIZE];
    rz->index->size ++;
}

static void save_zindex(RAZF *rz, int fd)
{
    int32_t i;
    int32_t v32;
    int is_be;

    is_be = is_big_endian();
    if (is_be)
        write(fd, &rz->index->size, sizeof(int));
    else
    {
        v32 = byte_swap_4((uint32_t)rz->index->size);
        write(fd, &v32, sizeof(uint32_t));
    }
    v32 = rz->index->size / RZ_BIN_SIZE + 1;
    if (!is_be)
    {
        for (i=0; i < v32; i++)
            rz->index->bin_offsets[i]  = byte_swap_8((uint64_t)rz->index->bin_offsets[i]);
        for (i=0; i < rz->index->size; i++)
            rz->index->cell_offsets[i] = byte_swap_4((uint32_t)rz->index->cell_offsets[i]);
    }
    write(fd, rz->index->bin_offsets, sizeof(int64_t) * v32);
    write(fd, rz->index->cell_offsets, sizeof(int32_t) * rz->index->size);
}
#endif

static void load_zindex(RAZF *rz, int fd)
{
    int32_t i, v32;
    int is_be;

    if (!rz->load_index)
        return;
    if (rz->index == NULL)
        rz->index = (ZBlockIndex*)malloc(sizeof(ZBlockIndex));
    is_be = is_big_endian();
    read(fd, &rz->index->size, sizeof(int));
    if (!is_be)
        rz->index->size = byte_swap_4((uint32_t)rz->index->size);
    rz->index->cap = rz->index->size;
    v32 = rz->index->size / RZ_BIN_SIZE + 1;
    rz->index->bin_offsets  = (int64_t*)malloc(sizeof(int64_t) * v32);
    read(fd, rz->index->bin_offsets, sizeof(int64_t) * v32);
    rz->index->cell_offsets = (uint32_t*)malloc(sizeof(uint32_t) * rz->index->size);
    read(fd, rz->index->cell_offsets, sizeof(int) * rz->index->size);

    if (!is_be)
    {
        for (i=0; i < v32; i++)
            rz->index->bin_offsets[i] = byte_swap_8((uint64_t)rz->index->bin_offsets[i]);
        for (i=0; i < rz->index->size; i++)
            rz->index->cell_offsets[i] = byte_swap_4((uint32_t)rz->index->cell_offsets[i]);
    }
}

#ifdef _RZ_READONLY
static RAZF* razf_open_w(int fd)
{
    fprintf(stderr, "[razf_open_w] Writing is not available with zlib ver < 1.2.2.1\n");
    return 0;
}
#else
static RAZF* razf_open_w(int fd)
{
    RAZF *rz;
#ifdef _WIN32
    setmode(fd, O_BINARY);
#endif
    rz = (RAZF*)calloc(1, sizeof(RAZF));
    rz->mode = 'w';
    rz->filedes = fd;
    rz->stream = (z_stream*)calloc(sizeof(z_stream), 1);
    rz->inbuf  = malloc(RZ_BUFFER_SIZE);
    rz->outbuf = malloc(RZ_BUFFER_SIZE);
    rz->index = (ZBlockIndex*)calloc(sizeof(ZBlockIndex), 1);
    deflateInit2(rz->stream, RZ_COMPRESS_LEVEL, Z_DEFLATED, WINDOW_BITS + 16, DEF_MEM_LEVEL, Z_DEFAULT_STRATEGY);
    rz->stream->avail_out = RZ_BUFFER_SIZE;
    rz->stream->next_out  = (Bytef*)rz->outbuf;
    rz->header = (gz_header*)calloc(sizeof(gz_header), 1);
    rz->header->os    = 0x03; //Unix
    rz->header->text  = 0;
    rz->header->time  = 0;
    rz->header->extra = (Bytef*)malloc(7);
    strncpy((char*)rz->header->extra, "RAZF", 4);
    rz->header->extra[4] = 1; // obsolete field
    // block size = RZ_BLOCK_SIZE, Big-Endian
    rz->header->extra[5] = RZ_BLOCK_SIZE >> 8;
    rz->header->extra[6] = RZ_BLOCK_SIZE & 0xFF;
    rz->header->extra_len = 7;
    rz->header->name = rz->header->comment  = 0;
    rz->header->hcrc = 0;
    deflateSetHeader(rz->stream, rz->header);
    rz->block_pos = rz->block_off = 0;

    return rz;
}

static void _razf_write(RAZF* rz, const void *data, int size)
{
    int tout;

    rz->stream->avail_in = size;
    rz->stream->next_in  = (Bytef*)data;

    while (1)
    {
        tout = rz->stream->avail_out;
        deflate(rz->stream, Z_NO_FLUSH);
        rz->out += tout - rz->stream->avail_out;
        if (rz->stream->avail_out)
            break;
        write(rz->filedes, rz->outbuf, RZ_BUFFER_SIZE - rz->stream->avail_out);
        rz->stream->avail_out = RZ_BUFFER_SIZE;
        rz->stream->next_out  = (Bytef*)rz->outbuf;
        if (rz->stream->avail_in == 0)
            break;
    };
    rz->in += size - rz->stream->avail_in;
    rz->block_off += size - rz->stream->avail_in;
}

static void razf_flush(RAZF *rz)
{
    uint32_t tout;

    if (rz->buf_len)
    {
        _razf_write(rz, rz->inbuf, rz->buf_len);
        rz->buf_off = rz->buf_len = 0;
    }

    if (rz->stream->avail_out)
    {
        write(rz->filedes, rz->outbuf, RZ_BUFFER_SIZE - rz->stream->avail_out);
        rz->stream->avail_out = RZ_BUFFER_SIZE;
        rz->stream->next_out  = (Bytef*)rz->outbuf;
    }

    while (1)
    {
        tout = rz->stream->avail_out;
        deflate(rz->stream, Z_FULL_FLUSH);
        rz->out += tout - rz->stream->avail_out;
        if (rz->stream->avail_out == 0)
        {
            write(rz->filedes, rz->outbuf, RZ_BUFFER_SIZE - rz->stream->avail_out);
            rz->stream->avail_out = RZ_BUFFER_SIZE;
            rz->stream->next_out  = (Bytef*)rz->outbuf;
        }
        else
            break;
    }

    rz->block_pos = rz->out;
    rz->block_off = 0;
}

static void razf_end_flush(RAZF *rz)
{
    uint32_t tout;

    if (rz->buf_len)
    {
        _razf_write(rz, rz->inbuf, rz->buf_len);
        rz->buf_off = rz->buf_len = 0;
    }

    while (1)
    {
        tout = rz->stream->avail_out;
        deflate(rz->stream, Z_FINISH);
        rz->out += tout - rz->stream->avail_out;
        if(rz->stream->avail_out < RZ_BUFFER_SIZE)
        {
            write(rz->filedes, rz->outbuf, RZ_BUFFER_SIZE - rz->stream->avail_out);
            rz->stream->avail_out = RZ_BUFFER_SIZE;
            rz->stream->next_out  = (Bytef*)rz->outbuf;
        }
        else
            break;
    }
}

static void _razf_buffered_write(RAZF *rz, const void *data, int size)
{
    int i, n;
    char *dd = (char*)data;

    while (1)
    {
        if (rz->buf_len == RZ_BUFFER_SIZE)
        {
            _razf_write(rz, rz->inbuf, rz->buf_len);
            rz->buf_len = 0;
        }

        if (size + rz->buf_len < RZ_BUFFER_SIZE)
        {
            for (i=0; i < size; i++)
                ((char*)rz->inbuf + rz->buf_len)[i] = dd[i];
            rz->buf_len += size;
            return;
        }
        else
        {
            n = RZ_BUFFER_SIZE - rz->buf_len;
            for (i=0; i < n; i++)
                ((char*)rz->inbuf + rz->buf_len)[i] = dd[i];
            size -= n;
            dd += n;
            rz->buf_len += n;
        }
    }
}

int razf_write(RAZF* rz, const void *data, int size)
{
    int ori_size;
    int n;
    int64_t next_block;
    char *dd = (char*)data;

    ori_size = size;
    next_block = ((rz->in/RZ_BLOCK_SIZE)+1)*RZ_BLOCK_SIZE;

    while (rz->in+rz->buf_len+size >= next_block)
    {
        n = next_block - rz->in - rz->buf_len;
        _razf_buffered_write(rz, (void*)dd, n);
        dd += n;
        size -= n;
        razf_flush(rz);
        add_zindex(rz, rz->in, rz->out);
        next_block = ((rz->in/RZ_BLOCK_SIZE)+1)*RZ_BLOCK_SIZE;
    }
    _razf_buffered_write(rz, (void*)dd, size);

    return ori_size;
}
#endif

static int _read_gz_header(unsigned char *data, int size, int *extra_off, int *extra_len)
{
    int method;
    int flags;
    int n;
    int len;

    if (size < 2)
        return 0;
    if ((data[0] != 0x1f) || (data[1] != 0x8b))
        return 0;
    if (size < 4)
        return 0;

    method = data[2];
    flags  = data[3];

    if ((method != Z_DEFLATED) || (flags & RESERVED))
        return 0;

    //skip 6 bytes
    n = 4 + 6;
    *extra_off = n + 2;
    *extra_len = 0;

    if (flags & EXTRA_FIELD)
    {
        if (size < n+2)
            return 0;
        len = ((int)data[n + 1] << 8) | data[n];
        n += 2;
        *extra_off = n;
        while (len)
        {
            if (n >= size)
                return 0;
            n++;
            len--;
        }
        *extra_len = n - (*extra_off);
    }
    if (flags & ORIG_NAME)
        while((n < size) && data[n++]);
    if (flags & COMMENT)
        while((n < size) && data[n++]);
    if (flags & HEAD_CRC)
    {
        if (n+2 > size)
            return 0;
        n += 2;
    }

    return n;
}

static RAZF* razf_open_r(int fd, int _load_index)
{
    RAZF *rz;
    int ext_off;
    int ext_len;
    int n;
    int is_be;
    int ret;
    int64_t end;
    unsigned char c[] = "RAZF";

    rz = (RAZF*)calloc(1, sizeof(RAZF));
    rz->mode = 'r';
#ifdef _WIN32
    setmode(fd, O_BINARY);
#endif
    rz->filedes = fd;
    rz->stream = (z_stream*)calloc(sizeof(z_stream), 1);
    rz->inbuf  = malloc(RZ_BUFFER_SIZE);
    rz->outbuf = malloc(RZ_BUFFER_SIZE);
    rz->end = rz->src_end = 0x7FFFFFFFFFFFFFFFLL;
    n = read(rz->filedes, rz->inbuf, RZ_BUFFER_SIZE);
    ret = _read_gz_header((unsigned char*)rz->inbuf, n, &ext_off, &ext_len);
    if (ret == 0)
    {
PLAIN_FILE:
        rz->in = n;
        rz->file_type = FILE_TYPE_PLAIN;
        memcpy(rz->outbuf, rz->inbuf, n);
        rz->buf_len = n;
        free(rz->stream);
        rz->stream = NULL;
        return rz;
    }
    rz->header_size = ret;
    ret = inflateInit2(rz->stream, -WINDOW_BITS);
    if (ret != Z_OK)
    {
        inflateEnd(rz->stream);
        goto PLAIN_FILE;
    }
    rz->stream->avail_in = n - rz->header_size;
    rz->stream->next_in  = (Bytef*)rz->inbuf + rz->header_size;
    rz->stream->avail_out = RZ_BUFFER_SIZE;
    rz->stream->next_out  = (Bytef*)rz->outbuf;
    rz->file_type = FILE_TYPE_GZ;
    rz->in = rz->header_size;
    rz->block_pos = rz->header_size;
    rz->next_block_pos = rz->header_size;
    rz->block_off = 0;

    if ((ext_len < 7) || (memcmp((Bytef*)rz->inbuf + ext_off, c, 4) != 0))
        return rz;
    if (((((unsigned char*)rz->inbuf)[ext_off + 5] << 8) | ((unsigned char*)rz->inbuf)[ext_off + 6]) != RZ_BLOCK_SIZE)
    {
        fprintf(stderr, " -- WARNING: RZ_BLOCK_SIZE is not %d, treat source as gz file.  in %s -- %s:%d --\n", RZ_BLOCK_SIZE, __FUNCTION__, __FILE__, __LINE__);
        return rz;
    }
    rz->load_index = _load_index;
    rz->file_type = FILE_TYPE_RZ;
    if(lseek(fd, -16, SEEK_END) == -1)
    {
UNSEEKABLE:
        rz->seekable = 0;
        rz->index = NULL;
        rz->src_end = rz->end = 0x7FFFFFFFFFFFFFFFLL;
    }
    else
    {
        is_be = is_big_endian();
        rz->seekable = 1;
        read(fd, &end, sizeof(int64_t));
        if (!is_be)
            rz->src_end = (int64_t)byte_swap_8((uint64_t)end);
        else
            rz->src_end = end;

        read(fd, &end, sizeof(int64_t));

        if (!is_be)
            rz->end = (int64_t)byte_swap_8((uint64_t)end);
        else
            rz->end = end;

        if (n > rz->end)
        {
            rz->stream->avail_in -= n - rz->end;
            n = rz->end;
        }

        if (rz->end > rz->src_end)
        {
            lseek(fd, rz->in, SEEK_SET);
            goto UNSEEKABLE;
        }

        if (lseek(fd, rz->end, SEEK_SET) != rz->end)
        {
            lseek(fd, rz->in, SEEK_SET);
            goto UNSEEKABLE;
        }

        load_zindex(rz, fd);
        lseek(fd, n, SEEK_SET);
    }

    return rz;
}

RAZF* razf_dopen(int fd, const char *mode)
{
    if (strstr(mode, "r"))
        return razf_open_r(fd, 1);
    else if (strstr(mode, "w"))
        return razf_open_w(fd);
    else
        return NULL;
}

RAZF* razf_dopen2(int fd, const char *mode)
{
    if (strstr(mode, "r"))
        return razf_open_r(fd, 0);
    else if (strstr(mode, "w"))
        return razf_open_w(fd);
    else
        return NULL;
}

static inline RAZF* _razf_open(const char *filename, const char *mode, int _load_index)
{
    int fd;
    RAZF *rz;

    if (strstr(mode, "r"))
    {
#ifdef _WIN32
        fd = open(filename, O_RDONLY | O_BINARY);
#else
        fd = open(filename, O_RDONLY);
#endif
        if (fd < 0)
            return NULL;
        rz = razf_open_r(fd, _load_index);
    }
    else if (strstr(mode, "w"))
    {
#ifdef _WIN32
        fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY, 0666);
#else
        fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
#endif
        if (fd < 0)
            return NULL;
        rz = razf_open_w(fd);
    }
    else
        return NULL;

    return rz;
}

RAZF* razf_open(const char *filename, const char *mode)
{
    return _razf_open(filename, mode, 1);
}

RAZF* razf_open2(const char *filename, const char *mode)
{
    return _razf_open(filename, mode, 0);
}

int razf_get_data_size(RAZF *rz, int64_t *u_size, int64_t *c_size)
{
    int64_t n;

    if ((rz->mode != 'r') && (rz->mode != 'R'))
        return 0;

    switch (rz->file_type)
    {
    case FILE_TYPE_PLAIN:
        if (rz->end == 0x7fffffffffffffffLL)
        {
            if ((n = lseek(rz->filedes, 0, SEEK_CUR)) == -1)
                return 0;
            rz->end = lseek(rz->filedes, 0, SEEK_END);
            lseek(rz->filedes, n, SEEK_SET);
        }
        *u_size = *c_size = rz->end;
        return 1;
    case FILE_TYPE_GZ :
        return 0;
    case FILE_TYPE_RZ :
        if (rz->src_end == rz->end)
            return 0;
        *u_size = rz->src_end;
        *c_size = rz->end;
        return 1;
    default:
        return 0;
    }
}

static int _razf_read(RAZF* rz, void *data, int size)
{
    int ret;
    int tin;

    if (rz->z_eof || rz->z_err)
        return 0;
    if (rz->file_type == FILE_TYPE_PLAIN)
    {
        ret = read(rz->filedes, data, size);
        if (ret == 0)
            rz->z_eof = 1;
        return ret;
    }
    rz->stream->avail_out = size;
    rz->stream->next_out  = (Bytef*)data;
    while (rz->stream->avail_out)
    {
        if (rz->stream->avail_in == 0)
        {
            if (rz->in >= rz->end)
            {
                rz->z_eof = 1;
                break;
            }

            if (rz->end - rz->in < RZ_BUFFER_SIZE)
                rz->stream->avail_in = read(rz->filedes, rz->inbuf, rz->end -rz->in);
            else
                rz->stream->avail_in = read(rz->filedes, rz->inbuf, RZ_BUFFER_SIZE);

            if (rz->stream->avail_in == 0)
            {
                rz->z_eof = 1;
                break;
            }
            rz->stream->next_in = (Bytef*)rz->inbuf;
        }

        tin = rz->stream->avail_in;
        ret = inflate(rz->stream, Z_BLOCK);
        rz->in += tin - rz->stream->avail_in;

        if ((ret == Z_NEED_DICT) || (ret == Z_MEM_ERROR) || (ret == Z_DATA_ERROR))
        {
            fprintf(stderr, "[_razf_read] inflate error: %d %s (at %s:%d)\n", ret, rz->stream->msg ? rz->stream->msg : "", __FILE__, __LINE__);
            rz->z_err = 1;
            break;
        }

        if (ret == Z_STREAM_END)
        {
            rz->z_eof = 1;
            break;
        }

        if ((rz->stream->data_type&128) && !(rz->stream->data_type&64))
        {
            rz->buf_flush = 1;
            rz->next_block_pos = rz->in;
            break;
        }
    }

    return size - rz->stream->avail_out;
}

int razf_read(RAZF *rz, void *data, int size)
{
    int ori_size;
    int i;
    char *dd = (char*)data;

    ori_size = size;
    while (size > 0)
    {
        if (rz->buf_len)
        {
            if (size < rz->buf_len)
            {
                for (i=0; i < size; i++)
                    dd[i] = ((char*)rz->outbuf + rz->buf_off)[i];
                rz->buf_off += size;
                rz->buf_len -= size;
                dd += size;
                rz->block_off += size;
                size = 0;
                break;
            }
            else
            {
                for (i=0; i < rz->buf_len; i++)
                    dd[i] = ((char*)rz->outbuf + rz->buf_off)[i];
                dd += rz->buf_len;
                size -= rz->buf_len;
                rz->block_off += rz->buf_len;
                rz->buf_off = 0;
                rz->buf_len = 0;
                if (rz->buf_flush)
                {
                    rz->block_pos = rz->next_block_pos;
                    rz->block_off = 0;
                    rz->buf_flush = 0;
                }
            }
        }
        else if (rz->buf_flush)
        {
            rz->block_pos = rz->next_block_pos;
            rz->block_off = 0;
            rz->buf_flush = 0;
        }
        if (rz->buf_flush)
            continue;
        rz->buf_len = _razf_read(rz, rz->outbuf, RZ_BUFFER_SIZE);
        if (rz->z_eof && (rz->buf_len == 0))
            break;
    }

    rz->out += ori_size - size;

    return ori_size - size;
}

int razf_skip(RAZF* rz, int size)
{
    int ori_size;

    ori_size = size;

    while (size > 0)
    {
        if (rz->buf_len)
        {
            if (size < rz->buf_len)
            {
                rz->buf_off += size;
                rz->buf_len -= size;
                rz->block_off += size;
                size = 0;
                break;
            }
            else
            {
                size -= rz->buf_len;
                rz->buf_off = 0;
                rz->buf_len = 0;
                rz->block_off += rz->buf_len;
                if (rz->buf_flush)
                {
                    rz->block_pos = rz->next_block_pos;
                    rz->block_off = 0;
                    rz->buf_flush = 0;
                }
            }
        }
        else if (rz->buf_flush)
        {
            rz->block_pos = rz->next_block_pos;
            rz->block_off = 0;
            rz->buf_flush = 0;
        }

        if (rz->buf_flush)
            continue;
        rz->buf_len = _razf_read(rz, rz->outbuf, RZ_BUFFER_SIZE);
        if (rz->z_eof || rz->z_err)
            break;
    }

    rz->out += ori_size - size;

    return ori_size - size;
}

static void _razf_reset_read(RAZF *rz, int64_t in, int64_t out)
{
    lseek(rz->filedes, in, SEEK_SET);
    rz->in  = in;
    rz->out = out;
    rz->block_pos = in;
    rz->next_block_pos = in;
    rz->block_off = 0;
    rz->buf_flush = 0;
    rz->z_eof = rz->z_err = 0;
    inflateReset(rz->stream);
    rz->stream->avail_in = 0;
    rz->buf_off = rz->buf_len = 0;
}

int64_t razf_jump(RAZF *rz, int64_t block_start, int block_offset)
{
    int64_t pos;

    rz->z_eof = 0;

    if (rz->file_type == FILE_TYPE_PLAIN)
    {
        rz->buf_off = rz->buf_len = 0;
        pos = block_start + block_offset;
        pos = lseek(rz->filedes, pos, SEEK_SET);
        rz->out = rz->in = pos;
        return pos;
    }

    if ((block_start == rz->block_pos) && (block_offset >= rz->block_off))
    {
        block_offset -= rz->block_off;
        //needn't reset inflate
        goto SKIP;
    }

    //automaticly revist wrong block_start
    if (block_start  == 0)
        block_start = rz->header_size;

    _razf_reset_read(rz, block_start, 0);
SKIP:
    if (block_offset)
        razf_skip(rz, block_offset);

    return rz->block_off;
}

int64_t razf_seek(RAZF* rz, int64_t pos, int wher)
{
    int64_t idx;
    int64_t seek_pos;
    int64_t new_out;

    rz->z_eof = 0;

    if (wher == SEEK_CUR)
        pos += rz->out;
    else if (wher == SEEK_END)
        pos += rz->src_end;
    if (rz->file_type == FILE_TYPE_PLAIN)
    {
        seek_pos = lseek(rz->filedes, pos, SEEK_SET);
        rz->buf_off = rz->buf_len = 0;
        rz->out = rz->in = seek_pos;
        return seek_pos;
    }
    else if (rz->file_type == FILE_TYPE_GZ)
    {
        if (pos >= rz->out)
            goto SKIP;
        return rz->out;
    }
    if (pos == rz->out)
        return pos;
    if (pos > rz->src_end)
        return rz->out;
    if (!rz->seekable || !rz->load_index)
        if(pos >= rz->out)
            goto SKIP;
    idx = pos / RZ_BLOCK_SIZE - 1;
    seek_pos = (idx < 0) ? rz->header_size:(rz->index->cell_offsets[idx] + rz->index->bin_offsets[idx/RZ_BIN_SIZE]);
    new_out  = (idx+1) * RZ_BLOCK_SIZE;
    if ((pos > rz->out) && (new_out <= rz->out))
        goto SKIP;
    _razf_reset_read(rz, seek_pos, new_out);
SKIP:
    razf_skip(rz, (int)(pos - rz->out));

    return rz->out;
}

uint64_t razf_tell2(RAZF *rz)
{
    return (uint64_t)rz->block_pos<<16 | (rz->block_off & 0xffff);
}

int64_t razf_seek2(RAZF *rz, uint64_t voffset, int wher)
{
    if (wher != SEEK_SET)
        return -1;
    return razf_jump(rz, voffset>>16, voffset & 0xffff);
}

void razf_close(RAZF *rz)
{
    if (rz->mode == 'w')
    {
#ifndef _RZ_READONLY
        razf_end_flush(rz);
        deflateEnd(rz->stream);
        save_zindex(rz, rz->filedes);
        if (is_big_endian())
        {
            write(rz->filedes, &rz->in, sizeof(int64_t));
            write(rz->filedes, &rz->out, sizeof(int64_t));
        }
        else
        {
            uint64_t v64 = byte_swap_8((uint64_t)rz->in);
            write(rz->filedes, &v64, sizeof(int64_t));
            v64 = byte_swap_8((uint64_t)rz->out);
            write(rz->filedes, &v64, sizeof(int64_t));
        }
#endif
    }
    else if (rz->mode == 'r')
    {
        if(rz->stream)
            inflateEnd(rz->stream);
    }
    if (rz->inbuf)
        free(rz->inbuf);
    if (rz->outbuf)
        free(rz->outbuf);
    if (rz->header)
    {
        free(rz->header->extra);
        free(rz->header->name);
        free(rz->header->comment);
        free(rz->header);
    }
    if (rz->index)
    {
        free(rz->index->bin_offsets);
        free(rz->index->cell_offsets);
        free(rz->index);
    }
    free(rz->stream);
    close(rz->filedes);
    free(rz);
}

#endif