- added circular buffering for channels

- added stderr support for the client
- cleaned up a bunch of "unused" warnings, duplicated header definitions
- added exit-status support for the client

--HG--
extra : convert_revision : 5bdf806d8b440c87f7235414662f4189195618f4

circbuffer.h

@@ -0,0 +1,50 @@
+/*
+ * Dropbear SSH
+ * 
+ * Copyright (c) 2002-2004 Matt Johnston
+ * All rights reserved.
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE. */
+
+#ifndef _CIRCBUFFER_H_
+#define _CIRCBUFFER_H_
+struct circbuf {
+
+	unsigned int size;
+	unsigned int readpos;
+	unsigned int writepos;
+	unsigned int used;
+	unsigned char* data;
+};
+
+typedef struct circbuf circbuffer;
+
+circbuffer * cbuf_new(unsigned int size);
+void cbuf_free(circbuffer * cbuf);
+
+unsigned int cbuf_getused(circbuffer * cbuf); /* how much data stored */
+unsigned int cbuf_getavail(circbuffer * cbuf); /* how much we can write */
+unsigned int cbuf_readlen(circbuffer *cbuf); /* max linear read len */
+unsigned int cbuf_writelen(circbuffer *cbuf); /* max linear write len */
+
+unsigned char* cbuf_readptr(circbuffer *cbuf, unsigned int len);
+unsigned char* cbuf_writeptr(circbuffer *cbuf, unsigned int len);
+void cbuf_incrwrite(circbuffer *cbuf, unsigned int len);
+void cbuf_incrread(circbuffer *cbuf, unsigned int len);
+#endif