source: lib/iow-zlib.c @ 53f179f

4.0.1-hotfixescachetimestampsdevelopdpdk-ndagetsilivegetfragoffhelplibtrace4ndag_formatpfringrc-4.0.1rc-4.0.2rc-4.0.3rc-4.0.4ringdecrementfixringperformanceringtimestampfixes
Last change on this file since 53f179f was 22a9ccc, checked in by Shane Alcock <salcock@…>, 12 years ago
  • Updated licensing and documentation for all the IO writer modules
  • Got rid of annoying "Write thread leaving" message!
  • Added Id keyword support to all IO modules
  • Property mode set to 100644
File size: 4.2 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 <zlib.h>
36#include "wandio.h"
37#include <sys/types.h>
38#include <sys/stat.h>
39#include <fcntl.h>
40#include <stdlib.h>
41#include <string.h>
42
43/* Libtrace IO module implementing a zlib writer */
44
45enum err_t {
46        ERR_OK  = 1,
47        ERR_EOF = 0,
48        ERR_ERROR = -1
49};
50
51struct zlibw_t {
52        z_stream strm;
53        Bytef outbuff[1024*1024];
54        iow_t *child;
55        enum err_t err;
56        int inoffset;
57};
58
59
60extern iow_source_t zlib_wsource; 
61
62#define DATA(iow) ((struct zlibw_t *)((iow)->data))
63#define min(a,b) ((a)<(b) ? (a) : (b))
64
65iow_t *zlib_wopen(iow_t *child, int compress_level)
66{
67        iow_t *iow;
68        if (!child)
69                return NULL;
70        iow = malloc(sizeof(iow_t));
71        iow->source = &zlib_wsource;
72        iow->data = malloc(sizeof(struct zlibw_t));
73
74        DATA(iow)->child = child;
75
76        DATA(iow)->strm.next_in = NULL;
77        DATA(iow)->strm.avail_in = 0;
78        DATA(iow)->strm.next_out = DATA(iow)->outbuff;
79        DATA(iow)->strm.avail_out = sizeof(DATA(iow)->outbuff);
80        DATA(iow)->strm.zalloc = Z_NULL;
81        DATA(iow)->strm.zfree = Z_NULL;
82        DATA(iow)->strm.opaque = NULL;
83        DATA(iow)->err = ERR_OK;
84
85        deflateInit2(&DATA(iow)->strm, 
86                        compress_level, /* Level */
87                        Z_DEFLATED,     /* Method */
88                        15 | 16,        /* 15 bits of windowsize, 16 == use gzip header */
89                        9,              /* Use maximum (fastest) amount of memory usage */
90                        Z_DEFAULT_STRATEGY
91                );
92
93        return iow;
94}
95
96
97static off_t zlib_wwrite(iow_t *iow, const char *buffer, off_t len)
98{
99        if (DATA(iow)->err == ERR_EOF) {
100                return 0; /* EOF */
101        }
102        if (DATA(iow)->err == ERR_ERROR) {
103                return -1; /* ERROR! */
104        }
105
106        DATA(iow)->strm.next_in = (Bytef*)buffer; /* This casts away const, but it's really const
107                                                   * anyway
108                                                   */
109        DATA(iow)->strm.avail_in = len;
110
111        while (DATA(iow)->err == ERR_OK && DATA(iow)->strm.avail_in > 0) {
112                while (DATA(iow)->strm.avail_out <= 0) {
113                        int bytes_written = wandio_wwrite(DATA(iow)->child, 
114                                (char *)DATA(iow)->outbuff,
115                                sizeof(DATA(iow)->outbuff));
116                        if (bytes_written <= 0) { /* Error */
117                                DATA(iow)->err = ERR_ERROR;
118                                /* Return how much data we managed to write ok */
119                                if (DATA(iow)->strm.avail_in != len) {
120                                        return len-DATA(iow)->strm.avail_in;
121                                }
122                                /* Now return error */
123                                return -1;
124                        }
125                        DATA(iow)->strm.next_out = DATA(iow)->outbuff;
126                        DATA(iow)->strm.avail_out = sizeof(DATA(iow)->outbuff);
127                }
128                /* Decompress some data into the output buffer */
129                int err=deflate(&DATA(iow)->strm, 0);
130                switch(err) {
131                        case Z_OK:
132                                DATA(iow)->err = ERR_OK;
133                                break;
134                        default:
135                                DATA(iow)->err = ERR_ERROR;
136                }
137        }
138        /* Return the number of bytes decompressed */
139        return len-DATA(iow)->strm.avail_in;
140}
141
142static void zlib_wclose(iow_t *iow)
143{
144        while (deflate(&DATA(iow)->strm, Z_FINISH) == Z_OK) {
145                /* Need to flush the output buffer */
146                wandio_wwrite(DATA(iow)->child, 
147                                (char*)DATA(iow)->outbuff,
148                                sizeof(DATA(iow)->outbuff)-DATA(iow)->strm.avail_out);
149                DATA(iow)->strm.next_out = DATA(iow)->outbuff;
150                DATA(iow)->strm.avail_out = sizeof(DATA(iow)->outbuff);
151        }
152        deflateEnd(&DATA(iow)->strm);
153        wandio_wwrite(DATA(iow)->child, 
154                        (char *)DATA(iow)->outbuff,
155                        sizeof(DATA(iow)->outbuff)-DATA(iow)->strm.avail_out);
156        wandio_wdestroy(DATA(iow)->child);
157        free(iow->data);
158        free(iow);
159}
160
161iow_source_t zlib_wsource = {
162        "zlibw",
163        zlib_wwrite,
164        zlib_wclose
165};
166
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