/*
* ngIRCd -- The Next Generation IRC Daemon
- * Copyright (c)2001-2006 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 ZLIB
/* enable more zlib related debug messages: */
/* #define DEBUG_ZLIB */
-static char UNUSED id[] = "$Id: conn-zip.c,v 1.12 2007/05/09 08:55:14 fw Exp $";
-
#include "imp.h"
#include <assert.h>
#include <string.h>
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 );
+ 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.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 );
+ 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, size_t Len )
+Zip_Buffer( CONN_ID Idx, const char *Data, size_t Len )
{
size_t buflen;
assert( Len > 0 );
buflen = array_bytes(&My_Connections[Idx].zip.wbuf);
- if (buflen >= WRITEBUFFER_LEN) {
+ if (buflen + Len >= WRITEBUFFER_SLINK_LEN) {
/* compression buffer is full, flush */
if( ! Zip_Flush( Idx )) return false;
}
/* 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 >= WRITEBUFFER_LEN)
+ 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;
- unsigned char zipbuf[WRITEBUFFER_LEN];
+ unsigned char zipbuf[WRITEBUFFER_SLINK_LEN];
int zipbuf_used = 0;
z_stream *out;
out = &My_Connections[Idx].zip.out;
- out->next_in = array_start(&My_Connections[Idx].zip.wbuf);
- if (!out->next_in)
- return false;
-
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;
return false;
}
- assert(out->avail_out <= WRITEBUFFER_LEN);
- assert(out->avail_out > 0); /* 0 might indicate not all data was compressed... */
- zipbuf_used = WRITEBUFFER_LEN - out->avail_out;
+ 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))
+ (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);
} /* 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;
unsigned char unzipbuf[READBUFFER_LEN];
int unzipbuf_used = 0;
return true;
in = &My_Connections[Idx].zip.in;
-
+
in->next_in = array_start(&My_Connections[Idx].zip.rbuf);
- if (!in->next_in)
- return false;
+ assert(in->next_in != NULL);
in->avail_in = z_rdatalen;
in->next_out = unzipbuf;
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;
}
#endif
assert(unzipbuf_used <= READBUFFER_LEN);
if (!array_catb(&My_Connections[Idx].rbuf, (char*) unzipbuf,
- (size_t)unzipbuf_used))
+ (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 {
} /* 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 */
projects / ngircd-alex.git / blobdiff