patch-2.1.132 linux/net/irda/irlap_comp.c

• Lines: 352
• Date: Fri Dec 18 08:06:39 1998
• Orig file: v2.1.131/linux/net/irda/irlap_comp.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.1.131/linux/net/irda/irlap_comp.c linux/net/irda/irlap_comp.c
@@ -0,0 +1,351 @@
+/*********************************************************************
+ *                
+ * Filename:      irlap_comp.c
+ * Version:       
+ * Description:   
+ * Status:        Experimental.
+ * Author:        Dag Brattli <dagb@cs.uit.no>
+ * Created at:    Fri Oct  9 09:18:07 1998
+ * Modified at:   Mon Dec 14 11:55:27 1998
+ * Modified by:   Dag Brattli <dagb@cs.uit.no>
+ * Sources:       ppp.c, isdn_ppp.c
+ * 
+ *     Copyright (c) 1998 Dag Brattli, All Rights Reserved.
+ *      
+ *     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.
+ *  
+ *     Neither Dag Brattli nor University of Tromsų admit liability nor
+ *     provide warranty for any of this software. This material is 
+ *     provided "AS-IS" and at no charge.
+ *     
+ ********************************************************************/
+
+#include <net/irda/irda.h>
+#include <net/irda/irqueue.h>
+#include <net/irda/irlap.h>
+#include <net/irda/irlap_comp.h>
+#include "../../drivers/net/zlib.h"
+
+hashbin_t *irlap_compressors = NULL;
+
+/*
+ * Function irda_register_compressor (cp)
+ *
+ *    Register new compressor with the IrLAP
+ *
+ */
+int irda_register_compressor( struct compressor *cp)
+{
+	struct irda_compressor *new;
+
+	DEBUG( 4, __FUNCTION__ "()\n");
+
+	/* Check if this compressor has been registred before */
+	if ( hashbin_find ( irlap_compressors, cp->compress_proto, NULL)) {
+		DEBUG( 0, __FUNCTION__ "(), Compressor already registered\n");
+                return 0;
+        }
+	
+	/* Make new IrDA compressor */
+        new = (struct irda_compressor *) 
+		kmalloc( sizeof( struct irda_compressor), GFP_KERNEL);
+        if (new == NULL)
+                return 1;
+		
+	memset( new, 0, sizeof( struct irda_compressor));
+        new->cp = cp;
+
+	/* Insert IrDA compressor into hashbin */
+	hashbin_insert( irlap_compressors, (QUEUE *) new, cp->compress_proto,
+			NULL);
+	
+        return 0;
+}
+
+/*
+ * Function irda_unregister_compressor (cp)
+ *
+ *    Unregister compressor
+ *
+ */
+void irda_unregister_compressor ( struct compressor *cp)
+{
+	struct irda_compressor *node;
+
+	DEBUG( 4, __FUNCTION__ "()\n");
+
+	node = hashbin_remove( irlap_compressors, cp->compress_proto, NULL);
+	if ( !node) {
+		DEBUG( 0, __FUNCTION__ "(), compressor not found!\n");
+		return;
+	}
+	
+	kfree( node);
+}
+
+/*
+ * Function irda_set_compression (self, proto)
+ *
+ *    The the compression protocol to be used by this session
+ *
+ */
+int irda_set_compression( struct irlap_cb *self, int proto)
+{
+	struct compressor *cp;
+	struct irda_compressor *comp;
+
+	__u8 options[CILEN_DEFLATE];
+
+	DEBUG( 0, __FUNCTION__ "()\n");
+
+	ASSERT( self != NULL, return -ENODEV;);
+	ASSERT( self->magic == LAP_MAGIC, return -EBADR;);
+
+	/* Initialize options */
+	options[0] = CI_DEFLATE;
+	options[1] = CILEN_DEFLATE;
+	options[2] = DEFLATE_METHOD( DEFLATE_METHOD_VAL);
+	options[3] = DEFLATE_CHK_SEQUENCE;
+
+	comp = hashbin_find( irlap_compressors, proto, NULL);
+	if ( !comp) {
+		DEBUG( 0, __FUNCTION__ "(), Unable to find compressor\n");
+		return -1;
+	}
+
+	cp = comp->cp;
+	/* 
+	 *  Compressor part
+	 */
+	if ( self->compressor.state != NULL)
+		(*self->compressor.cp->comp_free)( self->compressor.state);
+	self->compressor.state = NULL;
+	
+	self->compressor.cp = cp;
+	self->compressor.state = cp->comp_alloc( options, sizeof( options));
+	if ( self->compressor.state == NULL) {
+		DEBUG( 0, __FUNCTION__ "(), Failed!\n");
+		return -ENOBUFS;
+	}
+
+	/* 
+	 *  Decompress part
+	 */
+	
+	if ( self->decompressor.state != NULL)
+		irda_decomp_free( self->decompressor.state);
+	self->decompressor.state = NULL;
+	
+	self->decompressor.cp = cp;
+	self->decompressor.state = cp->decomp_alloc( options, sizeof( options));
+	if ( self->decompressor.state == NULL) {
+		DEBUG( 0, __FUNCTION__ "(), Failed!\n");
+		return -ENOBUFS;
+	}
+	return 0;
+}
+
+/*
+ * Function irda_free_compression (self)
+ *
+ *    
+ *
+ */
+void irda_free_compression( struct irlap_cb *self)
+{
+	DEBUG( 4, __FUNCTION__ "()\n");
+
+	if ( self->compressor.state) {
+		irda_comp_free( self->compressor.state);
+		self->compressor.state = NULL;
+	}
+	
+	if ( self->decompressor.state) {
+		irda_decomp_free( self->decompressor.state);
+		self->decompressor.state = NULL;
+	}
+}
+
+/*
+ * Function irlap_compress_init (self)
+ *
+ *    
+ *
+ */
+void irlap_compressor_init( struct irlap_cb *self, int compress)
+{
+	int debug = TRUE;
+	__u8 options[CILEN_DEFLATE];
+
+	DEBUG( 0, __FUNCTION__ "()\n");
+
+	ASSERT( self != NULL, return;);
+	ASSERT( self->magic == LAP_MAGIC, return;);
+	
+	/* Initialize options */
+	options[0] = CI_DEFLATE;
+	options[1] = CILEN_DEFLATE;
+	options[2] = DEFLATE_METHOD_VAL;
+	options[3] = DEFLATE_CHK_SEQUENCE;
+	
+	/*
+	 *  We're agreeing to send compressed packets.
+	 */
+	if ( self->compressor.state == NULL) {
+		DEBUG( 0, __FUNCTION__ "(), state == NULL\n");
+		return;
+	}
+	
+	if ((*self->compressor.cp->comp_init)( self->compressor.state, 
+					       options, sizeof( options),
+					       0, 0, debug)) 
+	{
+		DEBUG( 0, __FUNCTION__ "(), Compressor running!\n");
+		/* ppp->flags |= SC_COMP_RUN; */
+	}
+	
+	/*
+	 *  Initialize decompressor
+	 */
+	if ( self->decompressor.state == NULL) {
+		DEBUG( 0, __FUNCTION__ "(), state == NULL\n");
+		return;
+	}
+	
+	if (( self->decompressor.cp->decomp_init)( self->decompressor.state,
+						   options, sizeof( options),
+						   0, 0, 0, debug)) 
+	{
+		DEBUG( 0, __FUNCTION__ "(), Decompressor running!\n");	
+		
+		/* ppp->flags |= SC_DECOMP_RUN; */
+		/* ppp->flags &= ~(SC_DC_ERROR | SC_DC_FERROR); */
+	}
+}
+
+/*
+ * Function irlap_compress_frame (self, skb)
+ *
+ *
+ *
+ */
+struct sk_buff *irlap_compress_frame( struct irlap_cb *self, 
+				      struct sk_buff *skb)
+{
+	struct sk_buff *new_skb;
+	int count;
+	
+	ASSERT( skb != NULL, return NULL;);
+	
+	DEBUG( 0, __FUNCTION__ "() skb->len=%d, jiffies=%ld\n", (int) skb->len,
+	       jiffies);
+
+	ASSERT( self != NULL, return NULL;);
+	ASSERT( self->magic == LAP_MAGIC, return NULL;);
+
+	/* Check if compressor got initialized */
+	if ( self->compressor.state == NULL) {
+		/* Tell peer that this frame is not compressed */
+		skb_push( skb, LAP_COMP_HEADER);
+		skb->data[0] = IRDA_NORMAL;
+
+		return skb;
+	}
+
+	/* FIXME: Find out what is the max overhead (not 10) */
+	new_skb = dev_alloc_skb( skb->len+LAP_HEADER+10);
+	if(!new_skb)
+		return skb;
+
+	skb_reserve( new_skb, LAP_HEADER);
+	skb_put( new_skb, skb->len+10);
+	
+	count = (self->compressor.cp->compress)( self->compressor.state, 
+						 skb->data, new_skb->data, 
+						 skb->len, new_skb->len);
+	if( count <= 0) {
+		DEBUG( 0, __FUNCTION__ "(), Unable to compress frame!\n");
+		dev_kfree_skb( new_skb);
+
+		/* Tell peer that this frame is not compressed */
+		skb_push( skb, 1);
+		skb->data[0] = IRDA_NORMAL;
+
+		return skb;
+	}
+	skb_trim( new_skb, count);
+
+	/* Tell peer that this frame is compressed */
+	skb_push( new_skb, 1);
+	new_skb->data[0] = IRDA_COMPRESSED;
+
+	dev_kfree_skb( skb);
+	
+	DEBUG( 0, __FUNCTION__ "() new_skb->len=%d\n, jiffies=%ld", 
+	       (int) new_skb->len, jiffies);
+	
+	return new_skb;
+}
+
+/*
+ * Function irlap_decompress_frame (self, skb)
+ *
+ *    
+ *
+ */
+struct sk_buff *irlap_decompress_frame( struct irlap_cb *self, 
+					struct sk_buff *skb)
+{
+	struct sk_buff *new_skb;
+	int count;
+
+	DEBUG( 4, __FUNCTION__ "() skb->len=%d\n", (int) skb->len);
+
+	ASSERT( self != NULL, return NULL;);
+	ASSERT( self->magic == LAP_MAGIC, return NULL;);
+
+	ASSERT( self->compressor.state != NULL, return NULL;);
+
+	/* Check if frame is compressed */
+	if ( skb->data[0] == IRDA_NORMAL) {
+
+		/* Remove compression header */
+		skb_pull( skb, LAP_COMP_HEADER);
+
+		/*
+		 * The frame is not compressed. Pass it to the
+		 * decompression code so it can update its
+		 * dictionary if necessary.
+		 */
+		irda_incomp( self->decompressor.state, skb->data, skb->len);
+
+		return skb;
+	}
+
+	/* Remove compression header */
+	skb_pull( skb, LAP_COMP_HEADER);
+
+	new_skb = dev_alloc_skb( 2048); /* FIXME: find the right size */
+	if(!new_skb)
+		return skb;
+	skb_put( new_skb, 2048);
+
+	count = irda_decompress( self->decompressor.state, skb->data, 
+				 skb->len, new_skb->data, new_skb->len);
+	if ( count <= 0) {
+		DEBUG( 0, __FUNCTION__ "(), Unable to decompress frame!\n");
+		
+		dev_kfree_skb( new_skb);
+		return skb;
+	}
+
+	skb_trim( new_skb, count);
+	
+	DEBUG( 0, __FUNCTION__ "() new_skb->len=%d\n", (int) new_skb->len);
+
+	return new_skb;
+}
+