X-Git-Url: https://arthur.barton.de/cgi-bin/gitweb.cgi?p=ngircd-alex.git;a=blobdiff_plain;f=src%2Fngircd%2Fconn-zip.c;h=e21dd345777a35c599f308aee587c6dee377c4dd;hp=6ed53d60c895368be8fbbb2c4b0f599f559075fa;hb=f547981188a28844068e864dc1ed955ff173d216;hpb=8adff5922376676c2eeb49de1cbab86cc345b887

diff --git a/src/ngircd/conn-zip.c b/src/ngircd/conn-zip.c
index 6ed53d60..e21dd345 100644
--- a/src/ngircd/conn-zip.c
+++ b/src/ngircd/conn-zip.c
@@ -1,27 +1,28 @@
 /*
  * ngIRCd -- The Next Generation IRC Daemon
- * Copyright (c)2001,2002 by Alexander Barton (alex@barton.de)
+ * Copyright (c)2001-2014 Alexander Barton (alex@barton.de) and Contributors.
  *
  * 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
  */
 
+#define CONN_MODULE
 
 #include "portab.h"
 
-#define CONN_MODULE
+/**
+ * @file
+ * Connection compression using ZLIB
+ */
 
+/* Additionan debug messages related to ZIP compression: 0=off / 1=on */
+#define DEBUG_ZIP 0
 
 #ifdef ZLIB
 
-static char UNUSED id[] = "$Id: conn-zip.c,v 1.6 2005/03/19 18:43:48 fw Exp $";
-
-#include "imp.h"
 #include <assert.h>
 #include <string.h>
 #include <zlib.h>
@@ -29,15 +30,15 @@ static char UNUSED id[] = "$Id: conn-zip.c,v 1.6 2005/03/19 18:43:48 fw Exp $";
 #include "conn.h"
 #include "conn-func.h"
 #include "log.h"
+#include "array.h"
 
-#include "exp.h"
 #include "conn-zip.h"
 
 
 GLOBAL bool
 Zip_InitConn( CONN_ID Idx )
 {
-	/* Kompression fuer Link initialisieren */
+	/* initialize zlib compression on this link */
 
 	assert( Idx > NONE );
 
@@ -48,10 +49,8 @@ Zip_InitConn( CONN_ID Idx )
 	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 );
+	if (inflateInit( &My_Connections[Idx].zip.in ) != Z_OK) {
+		Log(LOG_ALERT, "Can't initialize compression on connection %d (zlib inflate)!", Idx);
 		return false;
 	}
 
@@ -61,64 +60,91 @@ Zip_InitConn( CONN_ID Idx )
 	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 );
+	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;
 } /* Zip_InitConn */
 
 
+/**
+ * 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, char *Data, int Len )
+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 ...*/
+	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 */
 
 
+/**
+ * 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 = (void *)My_Connections[Idx].zip.wbuf;
-	out->avail_in = My_Connections[Idx].zip.wdatalen;
-	out->next_out = (void *)(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;
 
+#if 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 ))
 	{
@@ -127,78 +153,125 @@ Zip_Flush( CONN_ID Idx )
 		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;
+#if 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;
+	}
+
+	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 */
 
 
+/**
+ * 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 = (void *)My_Connections[Idx].zip.rbuf;
-	in->avail_in = My_Connections[Idx].zip.rdatalen;
-	in->next_out = (void *)(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;
 
+#if 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: %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 );
+		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;
+#if 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;
 } /* Unzip_Buffer */
 
 
+/**
+ * @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 */
 
 
+/**
+ * @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 */