1 /*
2  * ngIRCd -- The Next Generation IRC Daemon
3  * Copyright (c)2001,2002 by Alexander Barton (alex@barton.de)
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License as published by
7  * the Free Software Foundation; either version 2 of the License, or
8  * (at your option) any later version.
9  * Please read the file COPYING, README and AUTHORS for more information.
10  *
11  * Connection compression using ZLIB
12  */
13 
14 
15 #include "portab.h"
16 
17 #define CONN_MODULE
18 
19 
20 #ifdef ZLIB
21 
22 static char UNUSED id[] = "$Id: conn-zip.c,v 1.5 2004/04/25 13:55:36 alex Exp $";
23 
24 #include "imp.h"
25 #include <assert.h>
26 #include <string.h>
27 #include <zlib.h>
28 
29 #include "conn.h"
30 #include "conn-func.h"
31 #include "log.h"
32 
33 #include "exp.h"
34 #include "conn-zip.h"
35 
36 
37 GLOBAL BOOLEAN
38 Zip_InitConn( CONN_ID Idx )
39 {
40 	/* Kompression fuer Link initialisieren */
41 
42 	assert( Idx > NONE );
43 
44 	My_Connections[Idx].zip.in.avail_in = 0;
45 	My_Connections[Idx].zip.in.total_in = 0;
46 	My_Connections[Idx].zip.in.total_out = 0;
47 	My_Connections[Idx].zip.in.zalloc = NULL;
48 	My_Connections[Idx].zip.in.zfree = NULL;
49 	My_Connections[Idx].zip.in.data_type = Z_ASCII;
50 
51 	if( inflateInit( &My_Connections[Idx].zip.in ) != Z_OK )
52 	{
53 		/* Fehler! */
54 		Log( LOG_ALERT, "Can't initialize compression on connection %d (zlib inflate)!", Idx );
55 		return FALSE;
56 	}
57 
58 	My_Connections[Idx].zip.out.total_in = 0;
59 	My_Connections[Idx].zip.out.total_in = 0;
60 	My_Connections[Idx].zip.out.zalloc = NULL;
61 	My_Connections[Idx].zip.out.zfree = NULL;
62 	My_Connections[Idx].zip.out.data_type = Z_ASCII;
63 
64 	if( deflateInit( &My_Connections[Idx].zip.out, Z_DEFAULT_COMPRESSION ) != Z_OK )
65 	{
66 		/* Fehler! */
67 		Log( LOG_ALERT, "Can't initialize compression on connection %d (zlib deflate)!", Idx );
68 		return FALSE;
69 	}
70 
71 	My_Connections[Idx].zip.bytes_in = My_Connections[Idx].bytes_in;
72 	My_Connections[Idx].zip.bytes_out = My_Connections[Idx].bytes_out;
73 
74 	Log( LOG_INFO, "Enabled link compression (zlib) on connection %d.", Idx );
75 	Conn_SetOption( Idx, CONN_ZIP );
76 
77 	return TRUE;
78 } /* Zip_InitConn */
79 
80 
81 GLOBAL BOOLEAN
82 Zip_Buffer( CONN_ID Idx, CHAR *Data, INT Len )
83 {
84 	/* Daten zum Komprimieren im "Kompressions-Puffer" sammeln.
85 	* Es wird TRUE bei Erfolg, sonst FALSE geliefert. */
86 
87 	assert( Idx > NONE );
88 	assert( Data != NULL );
89 	assert( Len > 0 );
90 
91 	/* Ist noch Platz im Kompressions-Puffer? */
92 	if( ZWRITEBUFFER_LEN - My_Connections[Idx].zip.wdatalen < Len + 50 )
93 	{
94 		/* Nein! Puffer zunaechst leeren ...*/
95 		if( ! Zip_Flush( Idx )) return FALSE;
96 	}
97 
98 	/* Daten kopieren */
99 	memmove( My_Connections[Idx].zip.wbuf + My_Connections[Idx].zip.wdatalen, Data, Len );
100 	My_Connections[Idx].zip.wdatalen += Len;
101 
102 	return TRUE;
103 } /* Zip_Buffer */
104 
105 
106 GLOBAL BOOLEAN
107 Zip_Flush( CONN_ID Idx )
108 {
109 	/* Daten komprimieren und in Schreibpuffer kopieren.
110 	* Es wird TRUE bei Erfolg, sonst FALSE geliefert. */
111 
112 	INT result, out_len;
113 	z_stream *out;
114 
115 	out = &My_Connections[Idx].zip.out;
116 
117 	out->next_in = (VOID *)My_Connections[Idx].zip.wbuf;
118 	out->avail_in = My_Connections[Idx].zip.wdatalen;
119 	out->next_out = (VOID *)(My_Connections[Idx].wbuf + My_Connections[Idx].wdatalen);
120 	out->avail_out = WRITEBUFFER_LEN - My_Connections[Idx].wdatalen;
121 
122 	result = deflate( out, Z_SYNC_FLUSH );
123 	if(( result != Z_OK ) || ( out->avail_in > 0 ))
124 	{
125 		Log( LOG_ALERT, "Compression error: code %d!?", result );
126 		Conn_Close( Idx, "Compression error!", NULL, FALSE );
127 		return FALSE;
128 	}
129 
130 	out_len = WRITEBUFFER_LEN - My_Connections[Idx].wdatalen - out->avail_out;
131 	My_Connections[Idx].wdatalen += out_len;
132 	My_Connections[Idx].bytes_out += out_len;
133 	My_Connections[Idx].zip.bytes_out += My_Connections[Idx].zip.wdatalen;
134 	My_Connections[Idx].zip.wdatalen = 0;
135 
136 	return TRUE;
137 } /* Zip_Flush */
138 
139 
140 GLOBAL BOOLEAN
141 Unzip_Buffer( CONN_ID Idx )
142 {
143 	/* Daten entpacken und in Lesepuffer kopieren. Bei Fehlern
144 	* wird FALSE geliefert, ansonsten TRUE. Der Fall, dass keine
145 	* Daten mehr zu entpacken sind, ist _kein_ Fehler! */
146 
147 	INT result, in_len, out_len;
148 	z_stream *in;
149 
150 	assert( Idx > NONE );
151 
152 	if( My_Connections[Idx].zip.rdatalen <= 0 ) return TRUE;
153 
154 	in = &My_Connections[Idx].zip.in;
155 
156 	in->next_in = (VOID *)My_Connections[Idx].zip.rbuf;
157 	in->avail_in = My_Connections[Idx].zip.rdatalen;
158 	in->next_out = (VOID *)(My_Connections[Idx].rbuf + My_Connections[Idx].rdatalen);
159 	in->avail_out = READBUFFER_LEN - My_Connections[Idx].rdatalen - 1;
160 
161 	result = inflate( in, Z_SYNC_FLUSH );
162 	if( result != Z_OK )
163 	{
164 		Log( LOG_ALERT, "Decompression error: %s (code=%d, ni=%d, ai=%d, no=%d, ao=%d)!?", in->msg, result, in->next_in, in->avail_in, in->next_out, in->avail_out );
165 		Conn_Close( Idx, "Decompression error!", NULL, FALSE );
166 		return FALSE;
167 	}
168 
169 	in_len = My_Connections[Idx].zip.rdatalen - in->avail_in;
170 	out_len = READBUFFER_LEN - My_Connections[Idx].rdatalen - 1 - in->avail_out;
171 	My_Connections[Idx].rdatalen += out_len;
172 
173 	if( in->avail_in > 0 )
174 	{
175 		/* es konnten nicht alle Daten entpackt werden, vermutlich war
176 		* im Ziel-Puffer kein Platz mehr. Umkopieren ... */
177 		My_Connections[Idx].zip.rdatalen -= in_len;
178 		memmove( My_Connections[Idx].zip.rbuf, My_Connections[Idx].zip.rbuf + in_len, My_Connections[Idx].zip.rdatalen );
179 	}
180 	else My_Connections[Idx].zip.rdatalen = 0;
181 	My_Connections[Idx].zip.bytes_in += out_len;
182 
183 	return TRUE;
184 } /* Unzip_Buffer */
185 
186 
187 GLOBAL LONG
188 Zip_SendBytes( CONN_ID Idx )
189 {
190 	/* Anzahl gesendeter Bytes (komprimiert!) liefern */
191 
192 	assert( Idx > NONE );
193 	return My_Connections[Idx].zip.bytes_out;
194 } /* Zip_SendBytes */
195 
196 
197 GLOBAL LONG
198 Zip_RecvBytes( CONN_ID Idx )
199 {
200 	/* Anzahl gesendeter Bytes (komprimiert!) liefern */
201 
202 	assert( Idx > NONE );
203 	return My_Connections[Idx].zip.bytes_in;
204 } /* Zip_RecvBytes */
205 
206 
207 #endif
208 
209 
210 /* -eof- */