[PATCH] uml: slirp and slip driver cleanups and fixes

This patch merges a lot of duplicated code in the slip and slirp drivers,
abstracts out the slip protocol, and makes the slip driver work in 2.6.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

arch/um/drivers/Makefile

@@ -22,8 +22,8 @@ obj-y := stdio_console.o fd.o chan_kern.o chan_user.o line.o
 obj-$(CONFIG_SSL) += ssl.o
 obj-$(CONFIG_STDERR_CONSOLE) += stderr_console.o
 
-obj-$(CONFIG_UML_NET_SLIP) += slip.o
-obj-$(CONFIG_UML_NET_SLIRP) += slirp.o
+obj-$(CONFIG_UML_NET_SLIP) += slip.o slip_common.o
+obj-$(CONFIG_UML_NET_SLIRP) += slirp.o slip_common.o
 obj-$(CONFIG_UML_NET_DAEMON) += daemon.o 
 obj-$(CONFIG_UML_NET_MCAST) += mcast.o 
 #obj-$(CONFIG_UML_NET_PCAP) += pcap.o $(PCAP)
@@ -41,6 +41,6 @@ obj-$(CONFIG_UML_WATCHDOG) += harddog.o
 obj-$(CONFIG_BLK_DEV_COW_COMMON) += cow_user.o
 obj-$(CONFIG_UML_RANDOM) += random.o
 
-USER_OBJS := fd.o null.o pty.o tty.o xterm.o
+USER_OBJS := fd.o null.o pty.o tty.o xterm.o slip_common.o
 
 include arch/um/scripts/Makefile.rules

arch/um/drivers/slip.h

@@ -1,39 +1,20 @@
 #ifndef __UM_SLIP_H
 #define __UM_SLIP_H
 
-#define BUF_SIZE 1500
- /* two bytes each for a (pathological) max packet of escaped chars +  * 
-  * terminating END char + initial END char                            */
-#define ENC_BUF_SIZE (2 * BUF_SIZE + 2)
+#include "slip_common.h"
 
 struct slip_data {
 	void *dev;
 	char name[sizeof("slnnnnn\0")];
 	char *addr;
 	char *gate_addr;
 	int slave;
-	unsigned char ibuf[ENC_BUF_SIZE];
-	unsigned char obuf[ENC_BUF_SIZE];
-	int more; /* more data: do not read fd until ibuf has been drained */
-	int pos;
-	int esc;
+	struct slip_proto slip;
 };
 
 extern struct net_user_info slip_user_info;
 
-extern int set_umn_addr(int fd, char *addr, char *ptp_addr);
 extern int slip_user_read(int fd, void *buf, int len, struct slip_data *pri);
 extern int slip_user_write(int fd, void *buf, int len, struct slip_data *pri);
 
 #endif
-
-/*
- * Overrides for Emacs so that we follow Linus's tabbing style.
- * Emacs will notice this stuff at the end of the file and automatically
- * adjust the settings for this buffer only.  This must remain at the end
- * of the file.
- * ---------------------------------------------------------------------------
- * Local variables:
- * c-file-style: "linux"
- * End:
- */

arch/um/drivers/slip_common.c

@@ -0,0 +1,54 @@
+#include <string.h>
+#include "slip_common.h"
+#include "net_user.h"
+
+int slip_proto_read(int fd, void *buf, int len, struct slip_proto *slip)
+{
+	int i, n, size, start;
+
+	if(slip->more > 0){
+		i = 0;
+		while(i < slip->more){
+			size = slip_unesc(slip->ibuf[i++], slip->ibuf,
+					  &slip->pos, &slip->esc);
+			if(size){
+				memcpy(buf, slip->ibuf, size);
+				memmove(slip->ibuf, &slip->ibuf[i],
+					slip->more - i);
+				slip->more = slip->more - i;
+				return size;
+			}
+		}
+		slip->more = 0;
+	}
+
+	n = net_read(fd, &slip->ibuf[slip->pos],
+		     sizeof(slip->ibuf) - slip->pos);
+	if(n <= 0)
+		return n;
+
+	start = slip->pos;
+	for(i = 0; i < n; i++){
+		size = slip_unesc(slip->ibuf[start + i], slip->ibuf,&slip->pos,
+				  &slip->esc);
+		if(size){
+			memcpy(buf, slip->ibuf, size);
+			memmove(slip->ibuf, &slip->ibuf[start+i+1],
+				n - (i + 1));
+			slip->more = n - (i + 1);
+			return size;
+		}
+	}
+	return 0;
+}
+
+int slip_proto_write(int fd, void *buf, int len, struct slip_proto *slip)
+{
+	int actual, n;
+
+	actual = slip_esc(buf, slip->obuf, len);
+	n = net_write(fd, slip->obuf, actual);
+	if(n < 0)
+		return n;
+	else return len;
+}

arch/um/drivers/slip_proto.h → arch/um/drivers/slip_common.h

@@ -1,10 +1,10 @@
-/* 
- * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
- * Licensed under the GPL
- */
+#ifndef __UM_SLIP_COMMON_H
+#define __UM_SLIP_COMMON_H
 
-#ifndef __UM_SLIP_PROTO_H__
-#define __UM_SLIP_PROTO_H__
+#define BUF_SIZE 1500
+ /* two bytes each for a (pathological) max packet of escaped chars +  *
+  * terminating END char + initial END char                            */
+#define ENC_BUF_SIZE (2 * BUF_SIZE + 2)
 
 /* SLIP protocol characters. */
 #define SLIP_END             0300	/* indicates end of frame	*/
@@ -80,15 +80,25 @@ static inline int slip_esc(unsigned char *s, unsigned char *d, int len)
 	return (ptr - d);
 }
 
-#endif
+struct slip_proto {
+	unsigned char ibuf[ENC_BUF_SIZE];
+	unsigned char obuf[ENC_BUF_SIZE];
+	int more; /* more data: do not read fd until ibuf has been drained */
+	int pos;
+	int esc;
+};
+
+#define SLIP_PROTO_INIT { \
+	.ibuf  	= { '\0' }, \
+	.obuf  	= { '\0' }, \
+        .more	= 0, \
+	.pos	= 0, \
+	.esc	= 0 \
+}
 
-/*
- * Overrides for Emacs so that we follow Linus's tabbing style.
- * Emacs will notice this stuff at the end of the file and automatically
- * adjust the settings for this buffer only.  This must remain at the end
- * of the file.
- * ---------------------------------------------------------------------------
- * Local variables:
- * c-file-style: "linux"
- * End:
- */
+extern int slip_proto_read(int fd, void *buf, int len,
+			   struct slip_proto *slip);
+extern int slip_proto_write(int fd, void *buf, int len,
+			    struct slip_proto *slip);
+
+#endif

arch/um/drivers/slip_kern.c

@@ -26,16 +26,16 @@ void slip_init(struct net_device *dev, void *data)
 		  .addr		= NULL,
 		  .gate_addr 	= init->gate_addr,
 		  .slave  	= -1,
-		  .ibuf  	= { '\0' },
-		  .obuf  	= { '\0' },
-		  .pos 		= 0,
-		  .esc 		= 0,
+		  .slip		= SLIP_PROTO_INIT,
 		  .dev 		= dev });
 
 	dev->init = NULL;
+	dev->header_cache_update = NULL;
+	dev->hard_header_cache = NULL;
+	dev->hard_header = NULL;
 	dev->hard_header_len = 0;
-	dev->addr_len = 4;
-	dev->type = ARPHRD_ETHER;
+	dev->addr_len = 0;
+	dev->type = ARPHRD_SLIP;
 	dev->tx_queue_len = 256;
 	dev->flags = IFF_NOARP;
 	printk("SLIP backend - SLIP IP = %s\n", spri->gate_addr);