/*
* ngIRCd -- The Next Generation IRC Daemon
- * Copyright (c)2001,2002 by Alexander Barton (alex@barton.de)
+ * Copyright (c)2001-2007 Alexander Barton (alex@barton.de)
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
* Please read the file COPYING, README and AUTHORS for more information.
- *
- * Connection compression using ZLIB
*/
-
#include "portab.h"
-#define CONN_MODULE
+/**
+ * @file
+ * Connection compression using ZLIB
+ */
+#define CONN_MODULE
-#ifdef USE_ZLIB
+#ifdef ZLIB
-static char UNUSED id[] = "$Id: conn-zip.c,v 1.2 2002/12/30 17:15:06 alex Exp $";
+/* enable more zlib related debug messages: */
+/* #define DEBUG_ZLIB */
#include "imp.h"
#include <assert.h>
#include "conn-func.h"
#include "log.h"
+#include "array.h"
#include "exp.h"
#include "conn-zip.h"
-GLOBAL BOOLEAN
+GLOBAL bool
Zip_InitConn( CONN_ID Idx )
{
- /* Kompression fuer Link initialisieren */
+ /* initialize zlib compression on this link */
assert( Idx > NONE );
My_Connections[Idx].zip.in.zfree = NULL;
My_Connections[Idx].zip.in.data_type = Z_ASCII;
- if( inflateInit( &My_Connections[Idx].zip.in ) != Z_OK )
- {
- /* Fehler! */
- Log( LOG_ALERT, "Can't initialize compression on connection %d (zlib inflate)!", Idx );
- return FALSE;
+ if (inflateInit( &My_Connections[Idx].zip.in ) != Z_OK) {
+ Log(LOG_ALERT, "Can't initialize compression on connection %d (zlib inflate)!", Idx);
+ return false;
}
My_Connections[Idx].zip.out.total_in = 0;
My_Connections[Idx].zip.out.zfree = NULL;
My_Connections[Idx].zip.out.data_type = Z_ASCII;
- if( deflateInit( &My_Connections[Idx].zip.out, Z_DEFAULT_COMPRESSION ) != Z_OK )
- {
- /* Fehler! */
- Log( LOG_ALERT, "Can't initialize compression on connection %d (zlib deflate)!", Idx );
- return FALSE;
+ if (deflateInit( &My_Connections[Idx].zip.out, Z_DEFAULT_COMPRESSION ) != Z_OK) {
+ Log(LOG_ALERT, "Can't initialize compression on connection %d (zlib deflate)!", Idx);
+ return false;
}
My_Connections[Idx].zip.bytes_in = My_Connections[Idx].bytes_in;
My_Connections[Idx].zip.bytes_out = My_Connections[Idx].bytes_out;
- Log( LOG_INFO, "Enabled link compression (zlib) on connection %d.", Idx );
- Conn_SetOption( Idx, CONN_ZIP );
+ Log(LOG_INFO, "Enabled link compression (zlib) on connection %d.", Idx);
+ Conn_OPTION_ADD( &My_Connections[Idx], CONN_ZIP );
- return TRUE;
+ return true;
} /* Zip_InitConn */
-GLOBAL BOOLEAN
-Zip_Buffer( CONN_ID Idx, CHAR *Data, INT Len )
+/**
+ * Copy data to the compression buffer of a connection. We do collect
+ * some data there until it's full so that we can achieve better
+ * compression ratios.
+ * If the (pre-)compression buffer is full, we try to flush it ("actually
+ * compress some data") and to add the new (uncompressed) data afterwards.
+ * This function closes the connection on error.
+ * @param Idx Connection handle.
+ * @param Data Pointer to the data.
+ * @param Len Length of the data to add.
+ * @return true on success, false otherwise.
+ */
+GLOBAL bool
+Zip_Buffer( CONN_ID Idx, const char *Data, size_t Len )
{
- /* Daten zum Komprimieren im "Kompressions-Puffer" sammeln.
- * Es wird TRUE bei Erfolg, sonst FALSE geliefert. */
+ size_t buflen;
assert( Idx > NONE );
assert( Data != NULL );
assert( Len > 0 );
- /* Ist noch Platz im Kompressions-Puffer? */
- if( ZWRITEBUFFER_LEN - My_Connections[Idx].zip.wdatalen < Len + 50 )
- {
- /* Nein! Puffer zunaechst leeren ...*/
- if( ! Zip_Flush( Idx )) return FALSE;
+ buflen = array_bytes(&My_Connections[Idx].zip.wbuf);
+ if (buflen + Len >= WRITEBUFFER_SLINK_LEN) {
+ /* compression buffer is full, flush */
+ if( ! Zip_Flush( Idx )) return false;
}
- /* Daten kopieren */
- memmove( My_Connections[Idx].zip.wbuf + My_Connections[Idx].zip.wdatalen, Data, Len );
- My_Connections[Idx].zip.wdatalen += Len;
-
- return TRUE;
+ /* check again; if zip buf is still too large do not append data:
+ * otherwise the zip wbuf would grow too large */
+ buflen = array_bytes(&My_Connections[Idx].zip.wbuf);
+ if (buflen + Len >= WRITEBUFFER_SLINK_LEN) {
+ Log(LOG_ALERT, "Zip Write buffer space exhausted: %lu bytes", buflen + Len);
+ Conn_Close(Idx, "Zip Write buffer space exhausted", NULL, false);
+ return false;
+ }
+ return array_catb(&My_Connections[Idx].zip.wbuf, Data, Len);
} /* Zip_Buffer */
-GLOBAL BOOLEAN
+/**
+ * Compress data in ZIP buffer and move result to the write buffer of
+ * the connection.
+ * This function closes the connection on error.
+ * @param Idx Connection handle.
+ * @return true on success, false otherwise.
+ */
+GLOBAL bool
Zip_Flush( CONN_ID Idx )
{
- /* Daten komprimieren und in Schreibpuffer kopieren.
- * Es wird TRUE bei Erfolg, sonst FALSE geliefert. */
-
- INT result, out_len;
+ int result;
+ unsigned char zipbuf[WRITEBUFFER_SLINK_LEN];
+ int zipbuf_used = 0;
z_stream *out;
out = &My_Connections[Idx].zip.out;
- out->next_in = My_Connections[Idx].zip.wbuf;
- out->avail_in = My_Connections[Idx].zip.wdatalen;
- out->next_out = My_Connections[Idx].wbuf + My_Connections[Idx].wdatalen;
- out->avail_out = WRITEBUFFER_LEN - My_Connections[Idx].wdatalen;
+ out->avail_in = (uInt)array_bytes(&My_Connections[Idx].zip.wbuf);
+ if (!out->avail_in)
+ return true; /* nothing to do. */
+
+ out->next_in = array_start(&My_Connections[Idx].zip.wbuf);
+ assert(out->next_in != NULL);
+ out->next_out = zipbuf;
+ out->avail_out = (uInt)sizeof zipbuf;
+
+#ifdef DEBUG_ZIP
+ Log(LOG_DEBUG, "out->avail_in %d, out->avail_out %d",
+ out->avail_in, out->avail_out);
+#endif
result = deflate( out, Z_SYNC_FLUSH );
if(( result != Z_OK ) || ( out->avail_in > 0 ))
{
Log( LOG_ALERT, "Compression error: code %d!?", result );
- Conn_Close( Idx, "Compression error!", NULL, FALSE );
- return FALSE;
+ Conn_Close( Idx, "Compression error!", NULL, false );
+ return false;
}
- out_len = WRITEBUFFER_LEN - My_Connections[Idx].wdatalen - out->avail_out;
- My_Connections[Idx].wdatalen += out_len;
- My_Connections[Idx].bytes_out += out_len;
- My_Connections[Idx].zip.bytes_out += My_Connections[Idx].zip.wdatalen;
- My_Connections[Idx].zip.wdatalen = 0;
+ if (out->avail_out <= 0) {
+ /* Not all data was compressed, because data became
+ * bigger while compressing it. */
+ Log(LOG_ALERT, "Compression error: buffer overflow!?");
+ Conn_Close(Idx, "Compression error!", NULL, false);
+ return false;
+ }
+
+ assert(out->avail_out <= WRITEBUFFER_SLINK_LEN);
+
+ zipbuf_used = WRITEBUFFER_SLINK_LEN - out->avail_out;
+#ifdef DEBUG_ZIP
+ Log(LOG_DEBUG, "zipbuf_used: %d", zipbuf_used);
+#endif
+ if (!array_catb(&My_Connections[Idx].wbuf,
+ (char *)zipbuf, (size_t) zipbuf_used)) {
+ Log (LOG_ALERT, "Compression error: can't copy data!?");
+ Conn_Close(Idx, "Compression error!", NULL, false);
+ return false;
+ }
- return TRUE;
+ My_Connections[Idx].bytes_out += zipbuf_used;
+ My_Connections[Idx].zip.bytes_out += array_bytes(&My_Connections[Idx].zip.wbuf);
+ array_trunc(&My_Connections[Idx].zip.wbuf);
+
+ return true;
} /* Zip_Flush */
-GLOBAL BOOLEAN
+/**
+ * uncompress data and copy it to read buffer.
+ * Returns true if data has been unpacked or no
+ * compressed data is currently pending in the zread buffer.
+ * This function closes the connection on error.
+ * @param Idx Connection handle.
+ * @return true on success, false otherwise.
+ */
+GLOBAL bool
Unzip_Buffer( CONN_ID Idx )
{
- /* Daten entpacken und in Lesepuffer kopieren. Bei Fehlern
- * wird FALSE geliefert, ansonsten TRUE. Der Fall, dass keine
- * Daten mehr zu entpacken sind, ist _kein_ Fehler! */
-
- INT result, in_len, out_len;
+ int result;
+ unsigned char unzipbuf[READBUFFER_LEN];
+ int unzipbuf_used = 0;
+ unsigned int z_rdatalen;
+ unsigned int in_len;
+
z_stream *in;
assert( Idx > NONE );
- if( My_Connections[Idx].zip.rdatalen <= 0 ) return TRUE;
+ z_rdatalen = (unsigned int)array_bytes(&My_Connections[Idx].zip.rbuf);
+ if (z_rdatalen == 0)
+ return true;
in = &My_Connections[Idx].zip.in;
- in->next_in = My_Connections[Idx].zip.rbuf;
- in->avail_in = My_Connections[Idx].zip.rdatalen;
- in->next_out = My_Connections[Idx].rbuf + My_Connections[Idx].rdatalen;
- in->avail_out = READBUFFER_LEN - My_Connections[Idx].rdatalen - 1;
+ in->next_in = array_start(&My_Connections[Idx].zip.rbuf);
+ assert(in->next_in != NULL);
+
+ in->avail_in = z_rdatalen;
+ in->next_out = unzipbuf;
+ in->avail_out = (uInt)sizeof unzipbuf;
+#ifdef DEBUG_ZIP
+ Log(LOG_DEBUG, "in->avail_in %d, in->avail_out %d",
+ in->avail_in, in->avail_out);
+#endif
result = inflate( in, Z_SYNC_FLUSH );
if( result != Z_OK )
{
- Log( LOG_ALERT, "Decompression error: code %d (ni=%d, ai=%d, no=%d, ao=%d)!?", result, in->next_in, in->avail_in, in->next_out, in->avail_out );
- Conn_Close( Idx, "Decompression error!", NULL, FALSE );
- return FALSE;
+ 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);
+ Conn_Close(Idx, "Decompression error!", NULL, false);
+ return false;
}
- in_len = My_Connections[Idx].zip.rdatalen - in->avail_in;
- out_len = READBUFFER_LEN - My_Connections[Idx].rdatalen - 1 - in->avail_out;
- My_Connections[Idx].rdatalen += out_len;
-
- if( in->avail_in > 0 )
- {
- /* es konnten nicht alle Daten entpackt werden, vermutlich war
- * im Ziel-Puffer kein Platz mehr. Umkopieren ... */
- My_Connections[Idx].zip.rdatalen -= in_len;
- memmove( My_Connections[Idx].zip.rbuf, My_Connections[Idx].zip.rbuf + in_len, My_Connections[Idx].zip.rdatalen );
+ assert(z_rdatalen >= in->avail_in);
+ in_len = z_rdatalen - in->avail_in;
+ unzipbuf_used = READBUFFER_LEN - in->avail_out;
+#ifdef DEBUG_ZIP
+ Log(LOG_DEBUG, "unzipbuf_used: %d - %d = %d", READBUFFER_LEN,
+ in->avail_out, unzipbuf_used);
+#endif
+ assert(unzipbuf_used <= READBUFFER_LEN);
+ if (!array_catb(&My_Connections[Idx].rbuf, (char*) unzipbuf,
+ (size_t)unzipbuf_used)) {
+ Log (LOG_ALERT, "Decompression error: can't copy data!?");
+ Conn_Close(Idx, "Decompression error!", NULL, false);
+ return false;
+ }
+ if( in->avail_in > 0 ) {
+ array_moveleft(&My_Connections[Idx].zip.rbuf, 1, in_len );
+ } else {
+ array_trunc( &My_Connections[Idx].zip.rbuf );
+ My_Connections[Idx].zip.bytes_in += unzipbuf_used;
}
- else My_Connections[Idx].zip.rdatalen = 0;
- My_Connections[Idx].zip.bytes_in += out_len;
- return TRUE;
+ return true;
} /* Unzip_Buffer */
-GLOBAL LONG
+/**
+ * @param Idx Connection handle.
+ * @return amount of sent (compressed) bytes
+ */
+GLOBAL long
Zip_SendBytes( CONN_ID Idx )
{
- /* Anzahl gesendeter Bytes (komprimiert!) liefern */
-
assert( Idx > NONE );
return My_Connections[Idx].zip.bytes_out;
} /* Zip_SendBytes */
-GLOBAL LONG
+/**
+ * @param Idx Connection handle.
+ * @return amount of received (compressed) bytes
+ */
+GLOBAL long
Zip_RecvBytes( CONN_ID Idx )
{
- /* Anzahl gesendeter Bytes (komprimiert!) liefern */
-
assert( Idx > NONE );
return My_Connections[Idx].zip.bytes_in;
} /* Zip_RecvBytes */