source: libwandio/ior-bzip.c @ 17f954f

4.0.1-hotfixescachetimestampsdevelopdpdk-ndagetsilivegetfragoffhelplibtrace4ndag_formatpfringrc-4.0.1rc-4.0.2rc-4.0.3rc-4.0.4ringdecrementfixringperformanceringtimestampfixes
Last change on this file since 17f954f was 60f3c4c, checked in by Shane Alcock <salcock@…>, 10 years ago
  • Shifted wandio into a separate library, seeing as we're going to be exporting the API now
  • Property mode set to 100644
File size: 3.7 KB
Line 
1/*
2 * This file is part of libtrace
3 *
4 * Copyright (c) 2007,2008,2009,2010 The University of Waikato, Hamilton,
5 * New Zealand.
6 *
7 * Authors: Daniel Lawson
8 *          Perry Lorier
9 *          Shane Alcock
10 *         
11 * All rights reserved.
12 *
13 * This code has been developed by the University of Waikato WAND
14 * research group. For further information please see http://www.wand.net.nz/
15 *
16 * libtrace is free software; you can redistribute it and/or modify
17 * it under the terms of the GNU General Public License as published by
18 * the Free Software Foundation; either version 2 of the License, or
19 * (at your option) any later version.
20 *
21 * libtrace is distributed in the hope that it will be useful,
22 * but WITHOUT ANY WARRANTY; without even the implied warranty of
23 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
24 * GNU General Public License for more details.
25 *
26 * You should have received a copy of the GNU General Public License
27 * along with libtrace; if not, write to the Free Software
28 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
29 *
30 * $Id$
31 *
32 */
33
34
35#include "wandio.h"
36#include <bzlib.h>
37#include <sys/types.h>
38#include <sys/stat.h>
39#include <fcntl.h>
40#include <stdlib.h>
41#include <string.h>
42#include <errno.h>
43
44/* Libtrace IO module implementing a bzip reader */
45
46enum err_t {
47        ERR_OK  = 1,
48        ERR_EOF = 0,
49        ERR_ERROR = -1
50};
51
52struct bz_t {
53        bz_stream strm;
54        char inbuff[1024*1024];
55        int outoffset;
56        io_t *parent;
57        enum err_t err;
58};
59
60
61extern io_source_t bz_source; 
62
63#define DATA(io) ((struct bz_t *)((io)->data))
64#define min(a,b) ((a)<(b) ? (a) : (b))
65
66io_t *bz_open(io_t *parent)
67{
68        io_t *io;
69        if (!parent)
70                return NULL;
71        io = malloc(sizeof(io_t));
72        io->source = &bz_source;
73        io->data = malloc(sizeof(struct bz_t));
74
75        DATA(io)->parent = parent;
76
77        DATA(io)->strm.next_in = NULL;
78        DATA(io)->strm.avail_in = 0;
79        DATA(io)->strm.next_out = NULL;
80        DATA(io)->strm.avail_out = 0;
81        DATA(io)->strm.bzalloc = NULL;
82        DATA(io)->strm.bzfree = NULL;
83        DATA(io)->strm.opaque = NULL;
84        DATA(io)->err = ERR_OK;
85
86        BZ2_bzDecompressInit(&DATA(io)->strm, 
87                0,      /* Verbosity */
88                0);     /* small */
89
90        return io;
91}
92
93
94static off_t bz_read(io_t *io, void *buffer, off_t len)
95{
96        if (DATA(io)->err == ERR_EOF)
97                return 0; /* EOF */
98        if (DATA(io)->err == ERR_ERROR) {
99                errno=EIO;
100                return -1; /* ERROR! */
101        }
102
103        DATA(io)->strm.avail_out = len;
104        DATA(io)->strm.next_out = buffer;
105
106        while (DATA(io)->err == ERR_OK && DATA(io)->strm.avail_out > 0) {
107                while (DATA(io)->strm.avail_in <= 0) {
108                        int bytes_read = wandio_read(DATA(io)->parent, 
109                                DATA(io)->inbuff,
110                                sizeof(DATA(io)->inbuff));
111                        if (bytes_read == 0) /* EOF */
112                                return len-DATA(io)->strm.avail_out;
113                        if (bytes_read < 0) { /* Error */
114                                /* Errno should already be set */
115                                DATA(io)->err = ERR_ERROR;
116                                /* Return how much data we managed to read ok */
117                                if (DATA(io)->strm.avail_out != (uint32_t)len) {
118                                        return len-DATA(io)->strm.avail_out;
119                                }
120                                /* Now return error */
121                                return -1;
122                        }
123                        DATA(io)->strm.next_in = DATA(io)->inbuff;
124                        DATA(io)->strm.avail_in = bytes_read;
125                }
126                /* Decompress some data into the output buffer */
127                int err=BZ2_bzDecompress(&DATA(io)->strm);
128                switch(err) {
129                        case BZ_OK:
130                                DATA(io)->err = ERR_OK;
131                                break;
132                        case BZ_STREAM_END:
133                                DATA(io)->err = ERR_EOF;
134                                break;
135                        default:
136                                errno=EIO;
137                                DATA(io)->err = ERR_ERROR;
138                }
139        }
140        /* Return the number of bytes decompressed */
141        return len-DATA(io)->strm.avail_out;
142}
143
144static void bz_close(io_t *io)
145{
146        BZ2_bzDecompressEnd(&DATA(io)->strm);
147        wandio_destroy(DATA(io)->parent);
148        free(io->data);
149        free(io);
150}
151
152io_source_t bz_source = {
153        "bzip",
154        bz_read,
155        NULL,   /* peek */
156        NULL,   /* tell */
157        NULL,   /* seek */
158        bz_close
159};
160
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