1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*************************************************************************
 *
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * Copyright 2000, 2010 Oracle and/or its affiliates.
 *
 * OpenOffice.org - a multi-platform office productivity suite
 *
 * This file is part of OpenOffice.org.
 *
 * OpenOffice.org is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License version 3
 * only, as published by the Free Software Foundation.
 *
 * OpenOffice.org is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License version 3 for more details
 * (a copy is included in the LICENSE file that accompanied this code).
 *
 * You should have received a copy of the GNU Lesser General Public License
 * version 3 along with OpenOffice.org.  If not, see
 * <http://www.openoffice.org/license.html>
 * for a copy of the LGPLv3 License.
 *
 ************************************************************************/

#include "precompile.h"

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <errno.h>
#include "hgzip.h"
#include "hstream.h"

#ifndef local
#  define local static
#endif

#define Z_BUFSIZE   (1024 * 4)

#define ALLOC(size) malloc(size)
#define TRYFREE(p) {if (p) free(p);}

#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 */

local int get_byte(gz_stream * s);
local int destroy(gz_stream * s);
local uLong getLong(gz_stream * s);

/* ===========================================================================
   Opens a gzip (.gz) file for reading or writing. The mode parameter
   is as in fopen ("rb" or "wb"). The file is given either by file descriptor
   or path name (if fd == -1).
     gz_open return NULL if the file could not be opened or if there was
   insufficient memory to allocate the (de)compression state; errno
   can be checked to distinguish the two cases (if errno is zero, the
   zlib error is Z_MEM_ERROR).
*/
gz_stream *gz_open(HStream & _stream)
{
    int err;
    //int level = Z_DEFAULT_COMPRESSION;            /* compression level */

//  char        *p = (char*)mode;
    //char fmode[80];                               /* copy of mode, without the compression level */
    //char *m = fmode;
    gz_stream *s;

    s = (gz_stream *) ALLOC(sizeof(gz_stream));
    if (!s)
        return Z_NULL;
    s->stream.zalloc = (alloc_func) 0;
    s->stream.zfree = (free_func) 0;
    s->stream.opaque = (voidpf) 0;
    s->stream.next_in = s->inbuf = Z_NULL;
    s->stream.next_out = s->outbuf = Z_NULL;
    s->stream.avail_in = s->stream.avail_out = 0;
//s->_inputstream = NULL;
    s->z_err = Z_OK;
    s->z_eof = 0;
    s->crc = crc32(0L, Z_NULL, 0);
    s->msg = NULL;
    s->transparent = 0;

    s->mode = 'r';

//realking
    err = inflateInit2(&(s->stream), -MAX_WBITS);
    s->stream.next_in = s->inbuf = (Byte *) ALLOC(Z_BUFSIZE);

    if (err != Z_OK || s->inbuf == Z_NULL)
    {
        return destroy(s), (gz_stream *) Z_NULL;<--- Consecutive return, break, continue, goto or throw statements are unnecessary.
    }

    s->stream.avail_out = Z_BUFSIZE;

    errno = 0;
    s->_inputstream = &_stream;

    return (gz_stream *) s;
}


/* ===========================================================================
     Read a byte from a gz_stream; update next_in and avail_in. Return EOF
   for end of file.
   IN assertion: the stream s has been sucessfully opened for reading.
*/
local int get_byte(gz_stream * s)
{
    if (s->z_eof)
        return EOF;
    if (s->stream.avail_in == 0)
    {
        errno = 0;

        s->stream.avail_in = s->_inputstream->readBytes(s->inbuf, Z_BUFSIZE);
        if (s->stream.avail_in == 0)
        {
            s->z_eof = 1;
            return EOF;
        }
        s->stream.next_in = s->inbuf;
    }
    s->stream.avail_in--;
    return *(s->stream.next_in)++;
}


/* ===========================================================================
 * Cleanup then free the given gz_stream. Return a zlib error code.
 * Try freeing in the reverse order of allocations.
 */
local int destroy(gz_stream * s)
{
    int err = Z_OK;

    if (!s)
        return Z_STREAM_ERROR;

    TRYFREE(s->msg);

    if (s->stream.state != NULL)
    {
        err = inflateEnd(&(s->stream));
    }
    if (s->z_err < 0)
        err = s->z_err;

    TRYFREE(s->inbuf);
    TRYFREE(s->outbuf);
    TRYFREE(s);
    return err;
}


// typedef unsigned char  Byte
// typedef Byte  FAR Bytef;
/* ===========================================================================
   Reads the given number of uncompressed bytes from the compressed file.
   gz_read returns the number of bytes actually read (0 for end of file).
*/
int gz_read(gz_stream * file, voidp buf, unsigned len)
{
//printf("@@ gz_read : len : %d\t",len);
    gz_stream *s = (gz_stream *) file;
    Bytef *start = (Bytef *) buf;                 /* starting point for crc computation */
    Byte *next_out;                               /* == stream.next_out but not forced far (for MSDOS) */
    if (s == NULL)
        return Z_STREAM_ERROR;

    if (s->z_err == Z_DATA_ERROR || s->z_err == Z_ERRNO)
        return -1;
    if (s->z_err == Z_STREAM_END)
        return 0;                                 /* EOF */

    s->stream.next_out = next_out = (Bytef *) buf;
    s->stream.avail_out = len;

    while (s->stream.avail_out != 0)
    {
        if (s->transparent)
        {
/* Copy first the lookahead bytes: */
            uInt n = s->stream.avail_in;

            if (n > s->stream.avail_out)
                n = s->stream.avail_out;
            if (n > 0)
            {
                memcpy(s->stream.next_out, s->stream.next_in, n);
                next_out += n;
                s->stream.next_out = next_out;
                s->stream.next_in += n;
                s->stream.avail_out -= n;
                s->stream.avail_in -= n;
            }
            if (s->stream.avail_out > 0)
            {
                s->stream.avail_out -=
                    s->_inputstream->readBytes(next_out, s->stream.avail_out);
            }
            return (int) (len - s->stream.avail_out);
        }
        if (s->stream.avail_in == 0 && !s->z_eof)
        {

            errno = 0;
            s->stream.avail_in = s->_inputstream->readBytes(s->inbuf, Z_BUFSIZE);
            if (s->stream.avail_in == 0)
            {
                s->z_eof = 1;
                break;
            }
            s->stream.next_in = s->inbuf;
        }
        s->z_err = inflate(&(s->stream), Z_NO_FLUSH);

        if (s->z_err == Z_STREAM_END)
        {
/* Check CRC and original size */
            s->crc = crc32(s->crc, start, (uInt) (s->stream.next_out - start));
            start = s->stream.next_out;

            if (getLong(s) != s->crc || getLong(s) != s->stream.total_out)
            {
                s->z_err = Z_DATA_ERROR;
            }
            else if (s->z_err == Z_OK)
            {
                inflateReset(&(s->stream));
                s->crc = crc32(0L, Z_NULL, 0);
            }
        }
        if (s->z_err != Z_OK || s->z_eof)
            break;
    }
    s->crc = crc32(s->crc, start, (uInt) (s->stream.next_out - start));
    return (int) (len - s->stream.avail_out);
}

/* ===========================================================================
     Flushes all pending output into the compressed file. The parameter
   flush is as in the deflate() function.
     gz_flush should be called only when strictly necessary because it can
   degrade compression.
*/
int gz_flush(gz_stream * file, int flush)
{
    uInt len;
    int done = 0;
    gz_stream *s = (gz_stream *) file;

    if (s == NULL || s->mode != 'w')
        return Z_STREAM_ERROR;

    s->stream.avail_in = 0;                       /* should be zero already anyway */

    for (;;)
    {
        len = Z_BUFSIZE - s->stream.avail_out;
        if (len != 0)
        {
/*
      if ((uInt)fwrite(s->outbuf, 1, len, s->file) != len) {
    s->z_err = Z_ERRNO;
    return Z_ERRNO;
      }
      */
            s->stream.next_out = s->outbuf;
            s->stream.avail_out = Z_BUFSIZE;
        }
        if (done)
            break;
        s->z_err = deflate(&(s->stream), flush);

/* deflate has finished flushing only when it hasn't used up
 * all the available space in the output buffer:
 */
        done = (s->stream.avail_out != 0 || s->z_err == Z_STREAM_END);

        if (s->z_err != Z_OK && s->z_err != Z_STREAM_END)
            break;
    }
    return s->z_err == Z_STREAM_END ? Z_OK : s->z_err;
}


/* ===========================================================================
   Reads a long in LSB order from the given gz_stream. Sets
*/
local uLong getLong(gz_stream * s)
{
    uLong x = (uLong) get_byte(s);
    int c;

    x += ((uLong) get_byte(s)) << 8;
    x += ((uLong) get_byte(s)) << 16;
    c = get_byte(s);
    if (c == EOF)
        s->z_err = Z_DATA_ERROR;
    x += ((uLong) c) << 24;
    return x;
}


/* ===========================================================================
   Flushes all pending output if necessary, closes the compressed file
   and deallocates all the (de)compression state.
*/
int gz_close(gz_stream * file)
{
//  int err;
    gz_stream *s = (gz_stream *) file;

    if (s == NULL)
        return Z_STREAM_ERROR;
#if 0
    if (s->mode == 'w')
    {
        err = gz_flush(file, Z_FINISH);
        if (err != Z_OK)
            return destroy(s);
        putLong(s->file, s->crc);
        putLong(s->file, s->stream.total_in);
    }
#endif
    return destroy(s);
}

/* vim:set shiftwidth=4 softtabstop=4 expandtab: */