/*
* 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
#ifdef ZLIB
-static char UNUSED id[] = "$Id: conn-zip.c,v 1.10 2006/05/10 21:24:01 alex Exp $";
+/* enable more zlib related debug messages: */
+/* #define DEBUG_ZLIB */
+
+static char UNUSED id[] = "$Id: conn-zip.c,v 1.16 2007/05/17 23:34:24 alex Exp $";
#include "imp.h"
#include <assert.h>
} /* 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.
+ * @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 )
{
- /* 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 );
- assert( Len <= ZWRITEBUFFER_LEN );
-
- if (Len > ZWRITEBUFFER_LEN)
- return false;
- if ( array_bytes( &My_Connections[Idx].zip.wbuf ) >= ZWRITEBUFFER_LEN ) {
+ 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;
}
+ /* 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)
+ 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.
+ * @param Idx Connection handle.
+ * @retrun 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;
- Log(LOG_DEBUG, "out->avail_in %d, out->avail_out %d", out->avail_in, out->avail_out);
+#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 ))
{
return false;
}
- assert(out->avail_out <= WRITEBUFFER_LEN);
- 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 overvlow!?");
+ 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);
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;
in->avail_out = (uInt)sizeof unzipbuf;
- Log(LOG_DEBUG, "in->avail_in %d, in->avail_out %d", in->avail_in, in->avail_out);
+#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 )
{
assert(z_rdatalen >= in->avail_in);
in_len = z_rdatalen - in->avail_in;
unzipbuf_used = READBUFFER_LEN - in->avail_out;
- Log(LOG_DEBUG, "unzipbuf_used: %d - %d = %d", READBUFFER_LEN, in->avail_out, unzipbuf_used);
+#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))