1 files changed, 93 insertions, 0 deletions

diff --git a/arch/um/drivers/slip_proto.h b/arch/um/drivers/slip_proto.h
new file mode 100644
index 000000000000..7206361ace45
--- /dev/null
+++ b/arch/um/drivers/slip_proto.h
@@ -0,0 +1,93 @@
+/* 
+ * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#ifndef __UM_SLIP_PROTO_H__
+#define __UM_SLIP_PROTO_H__
+
+/* SLIP protocol characters. */
+#define SLIP_END             0300       /* indicates end of frame       */
+#define SLIP_ESC             0333       /* indicates byte stuffing      */
+#define SLIP_ESC_END         0334       /* ESC ESC_END means END 'data' */
+#define SLIP_ESC_ESC         0335       /* ESC ESC_ESC means ESC 'data' */
+
+static inline int slip_unesc(unsigned char c,char *buf,int *pos, int *esc)
+{
+        int ret;
+
+        switch(c){
+        case SLIP_END:
+                *esc = 0;
+                ret=*pos;
+                *pos=0;
+                return(ret);
+        case SLIP_ESC:
+                *esc = 1;
+                return(0);
+        case SLIP_ESC_ESC:
+                if(*esc){
+                        *esc = 0;
+                        c = SLIP_ESC;
+                }
+                break;
+        case SLIP_ESC_END:
+                if(*esc){
+                        *esc = 0;
+                        c = SLIP_END;
+                }
+                break;
+        }
+        buf[(*pos)++] = c;
+        return(0);
+}
+
+static inline int slip_esc(unsigned char *s, unsigned char *d, int len)
+{
+        unsigned char *ptr = d;
+        unsigned char c;
+
+        /*
+         * Send an initial END character to flush out any
+         * data that may have accumulated in the receiver
+         * due to line noise.
+         */
+
+        *ptr++ = SLIP_END;
+
+        /*
+         * For each byte in the packet, send the appropriate
+         * character sequence, according to the SLIP protocol.
+         */
+
+        while (len-- > 0) {
+                switch(c = *s++) {
+                case SLIP_END:
+                        *ptr++ = SLIP_ESC;
+                        *ptr++ = SLIP_ESC_END;
+                        break;
+                case SLIP_ESC:
+                        *ptr++ = SLIP_ESC;
+                        *ptr++ = SLIP_ESC_ESC;
+                        break;
+                default:
+                        *ptr++ = c;
+                        break;
+                }
+        }
+        *ptr++ = SLIP_END;
+        return (ptr - d);
+}
+
+#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:
+ */