2 * ngIRCd -- The Next Generation IRC Daemon
3 * Copyright (c)2001-2007 Alexander Barton (alex@barton.de)
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.
16 * Connection compression using ZLIB
23 /* enable more zlib related debug messages: */
24 /* #define DEBUG_ZLIB */
32 #include "conn-func.h"
41 Zip_InitConn( CONN_ID Idx )
43 /* initialize zlib compression on this link */
47 My_Connections[Idx].zip.in.avail_in = 0;
48 My_Connections[Idx].zip.in.total_in = 0;
49 My_Connections[Idx].zip.in.total_out = 0;
50 My_Connections[Idx].zip.in.zalloc = NULL;
51 My_Connections[Idx].zip.in.zfree = NULL;
52 My_Connections[Idx].zip.in.data_type = Z_ASCII;
54 if (inflateInit( &My_Connections[Idx].zip.in ) != Z_OK) {
55 Log(LOG_ALERT, "Can't initialize compression on connection %d (zlib inflate)!", Idx);
59 My_Connections[Idx].zip.out.total_in = 0;
60 My_Connections[Idx].zip.out.total_in = 0;
61 My_Connections[Idx].zip.out.zalloc = NULL;
62 My_Connections[Idx].zip.out.zfree = NULL;
63 My_Connections[Idx].zip.out.data_type = Z_ASCII;
65 if (deflateInit( &My_Connections[Idx].zip.out, Z_DEFAULT_COMPRESSION ) != Z_OK) {
66 Log(LOG_ALERT, "Can't initialize compression on connection %d (zlib deflate)!", Idx);
70 My_Connections[Idx].zip.bytes_in = My_Connections[Idx].bytes_in;
71 My_Connections[Idx].zip.bytes_out = My_Connections[Idx].bytes_out;
73 Log(LOG_INFO, "Enabled link compression (zlib) on connection %d.", Idx);
74 Conn_OPTION_ADD( &My_Connections[Idx], CONN_ZIP );
81 * Copy data to the compression buffer of a connection. We do collect
82 * some data there until it's full so that we can achieve better
84 * If the (pre-)compression buffer is full, we try to flush it ("actually
85 * compress some data") and to add the new (uncompressed) data afterwards.
86 * This function closes the connection on error.
87 * @param Idx Connection handle.
88 * @param Data Pointer to the data.
89 * @param Len Length of the data to add.
90 * @return true on success, false otherwise.
93 Zip_Buffer( CONN_ID Idx, const char *Data, size_t Len )
98 assert( Data != NULL );
101 buflen = array_bytes(&My_Connections[Idx].zip.wbuf);
102 if (buflen + Len >= WRITEBUFFER_SLINK_LEN) {
103 /* compression buffer is full, flush */
104 if( ! Zip_Flush( Idx )) return false;
107 /* check again; if zip buf is still too large do not append data:
108 * otherwise the zip wbuf would grow too large */
109 buflen = array_bytes(&My_Connections[Idx].zip.wbuf);
110 if (buflen + Len >= WRITEBUFFER_SLINK_LEN) {
111 Log(LOG_ALERT, "Zip Write Buffer overflow: %lu bytes\n", buflen + Len);
112 Conn_Close(Idx, "Zip Write buffer overflow", NULL, false);
115 return array_catb(&My_Connections[Idx].zip.wbuf, Data, Len);
120 * Compress data in ZIP buffer and move result to the write buffer of
122 * This function closes the connection on error.
123 * @param Idx Connection handle.
124 * @return true on success, false otherwise.
127 Zip_Flush( CONN_ID Idx )
130 unsigned char zipbuf[WRITEBUFFER_SLINK_LEN];
134 out = &My_Connections[Idx].zip.out;
136 out->avail_in = (uInt)array_bytes(&My_Connections[Idx].zip.wbuf);
138 return true; /* nothing to do. */
140 out->next_in = array_start(&My_Connections[Idx].zip.wbuf);
141 assert(out->next_in != NULL);
143 out->next_out = zipbuf;
144 out->avail_out = (uInt)sizeof zipbuf;
147 Log(LOG_DEBUG, "out->avail_in %d, out->avail_out %d",
148 out->avail_in, out->avail_out);
150 result = deflate( out, Z_SYNC_FLUSH );
151 if(( result != Z_OK ) || ( out->avail_in > 0 ))
153 Log( LOG_ALERT, "Compression error: code %d!?", result );
154 Conn_Close( Idx, "Compression error!", NULL, false );
158 if (out->avail_out <= 0) {
159 /* Not all data was compressed, because data became
160 * bigger while compressing it. */
161 Log (LOG_ALERT, "Compression error: buffer overvlow!?");
162 Conn_Close(Idx, "Compression error!", NULL, false);
166 assert(out->avail_out <= WRITEBUFFER_SLINK_LEN);
168 zipbuf_used = WRITEBUFFER_SLINK_LEN - out->avail_out;
170 Log(LOG_DEBUG, "zipbuf_used: %d", zipbuf_used);
172 if (!array_catb(&My_Connections[Idx].wbuf,
173 (char *)zipbuf, (size_t) zipbuf_used)) {
174 Log (LOG_ALERT, "Compression error: can't copy data!?");
175 Conn_Close(Idx, "Compression error!", NULL, false);
179 My_Connections[Idx].bytes_out += zipbuf_used;
180 My_Connections[Idx].zip.bytes_out += array_bytes(&My_Connections[Idx].zip.wbuf);
181 array_trunc(&My_Connections[Idx].zip.wbuf);
188 * uncompress data and copy it to read buffer.
189 * Returns true if data has been unpacked or no
190 * compressed data is currently pending in the zread buffer.
191 * This function closes the connection on error.
192 * @param Idx Connection handle.
193 * @return true on success, false otherwise.
196 Unzip_Buffer( CONN_ID Idx )
199 unsigned char unzipbuf[READBUFFER_LEN];
200 int unzipbuf_used = 0;
201 unsigned int z_rdatalen;
206 assert( Idx > NONE );
208 z_rdatalen = (unsigned int)array_bytes(&My_Connections[Idx].zip.rbuf);
212 in = &My_Connections[Idx].zip.in;
214 in->next_in = array_start(&My_Connections[Idx].zip.rbuf);
215 assert(in->next_in != NULL);
217 in->avail_in = z_rdatalen;
218 in->next_out = unzipbuf;
219 in->avail_out = (uInt)sizeof unzipbuf;
222 Log(LOG_DEBUG, "in->avail_in %d, in->avail_out %d",
223 in->avail_in, in->avail_out);
225 result = inflate( in, Z_SYNC_FLUSH );
228 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);
229 Conn_Close(Idx, "Decompression error!", NULL, false);
233 assert(z_rdatalen >= in->avail_in);
234 in_len = z_rdatalen - in->avail_in;
235 unzipbuf_used = READBUFFER_LEN - in->avail_out;
237 Log(LOG_DEBUG, "unzipbuf_used: %d - %d = %d", READBUFFER_LEN,
238 in->avail_out, unzipbuf_used);
240 assert(unzipbuf_used <= READBUFFER_LEN);
241 if (!array_catb(&My_Connections[Idx].rbuf, (char*) unzipbuf,
242 (size_t)unzipbuf_used)) {
243 Log (LOG_ALERT, "Decompression error: can't copy data!?");
244 Conn_Close(Idx, "Decompression error!", NULL, false);
247 if( in->avail_in > 0 ) {
248 array_moveleft(&My_Connections[Idx].zip.rbuf, 1, in_len );
250 array_trunc( &My_Connections[Idx].zip.rbuf );
251 My_Connections[Idx].zip.bytes_in += unzipbuf_used;
259 * @param Idx Connection handle.
260 * @return amount of sent (compressed) bytes
263 Zip_SendBytes( CONN_ID Idx )
265 assert( Idx > NONE );
266 return My_Connections[Idx].zip.bytes_out;
267 } /* Zip_SendBytes */
271 * @param Idx Connection handle.
272 * @return amount of received (compressed) bytes
275 Zip_RecvBytes( CONN_ID Idx )
277 assert( Idx > NONE );
278 return My_Connections[Idx].zip.bytes_in;
279 } /* Zip_RecvBytes */