/*
 * Copyright (c) 1997-1999 University of Utah and the Flux Group.
 * All rights reserved.
 * 
 * This file is part of the Flux OSKit.  The OSKit is free software, also known
 * as "open source;" you can redistribute it and/or modify it under the terms
 * of the GNU General Public License (GPL), version 2, as published by the Free
 * Software Foundation (FSF).  To explore alternate licensing terms, contact
 * the University of Utah at csl-dist@cs.utah.edu or +1-801-585-3271.
 * 
 * The OSKit is distributed in the hope that it will be useful, but WITHOUT ANY
 * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 * FOR A PARTICULAR PURPOSE.  See the GPL for more details.  You should have
 * received a copy of the GPL along with the OSKit; see the file COPYING.  If
 * not, write to the FSF, 59 Temple Place #330, Boston, MA 02111-1307, USA.
 */
/*
 * IStream wrapper for a trivial device like a console
 * that is driven with a few simple functions.
 */

#include <oskit/com/trivial_stream.h>
#include <oskit/dev/dev.h>
#include <oskit/c/string.h>

static OSKIT_COMDECL
query(oskit_stream_t *si, const struct oskit_guid *iid, void **out_ihandle)
{
	struct oskit_trivial_stream *s = (struct oskit_trivial_stream*)si;

	if (memcmp(iid, &oskit_iunknown_iid, sizeof(*iid)) == 0 ||
	    memcmp(iid, &oskit_stream_iid, sizeof(*iid)) == 0) {
		*out_ihandle = &s->streami;
		return 0;
	}

	*out_ihandle = 0;
	return OSKIT_E_NOINTERFACE;
}

static OSKIT_COMDECL_U
add_ref(oskit_stream_t *si)
{
	return 1;
}

static OSKIT_COMDECL_U
release(oskit_stream_t *si)
{
	return 1;
}

static OSKIT_COMDECL
read(oskit_stream_t *si, void *buf, oskit_u32_t len, oskit_u32_t *out_actual)
{
	struct oskit_trivial_stream *s = (struct oskit_trivial_stream*)si;

	int i, c;
	for(i=0; i < len; ++i) {
		c = (*s->getchar)();
		if (c == -1) {
			if (i == 0)
				return OSKIT_E_FAIL;
			break;
		}
		((unsigned char*)buf)[i] = (unsigned char) c;
	}
	*out_actual = i;
	return 0;
}

static OSKIT_COMDECL
write(oskit_stream_t *si, const void *buf, oskit_u32_t len,
      oskit_u32_t *out_actual)
{
	struct oskit_trivial_stream *s = (struct oskit_trivial_stream*)si;

	int i=0;
	for(i=0; i < len; ++i)
		if ((*s->putchar)(((unsigned char*)buf)[i]) == -1) {
			if (i == 0)
				return OSKIT_EIO;
			break;
		}
	*out_actual = i;
	return 0;
}

static OSKIT_COMDECL
seek(oskit_stream_t *si, oskit_s64_t ofs, oskit_seek_t whence,
		  oskit_u64_t *out_newpos)
{
	return OSKIT_ESPIPE;
}

static OSKIT_COMDECL
setsize(oskit_stream_t *si, oskit_u64_t new_size)
{
	return OSKIT_EINVAL;
}

static OSKIT_COMDECL
copyto(oskit_stream_t *si, oskit_stream_t *dst,
	oskit_u64_t size, oskit_u64_t *out_read, oskit_u64_t *out_written)
{
	return OSKIT_E_NOTIMPL;	/*XXX*/
}

static OSKIT_COMDECL
commit(oskit_stream_t *si, oskit_u32_t commit_flags)
{
	return OSKIT_E_NOTIMPL;
}

static OSKIT_COMDECL
revert(oskit_stream_t *si)
{
	return OSKIT_E_NOTIMPL;
}

static OSKIT_COMDECL
lock_region(oskit_stream_t *si, oskit_u64_t offset,
			 oskit_u64_t size, oskit_u32_t lock_type)
{
	return OSKIT_E_NOTIMPL;
}

static OSKIT_COMDECL
unlock_region(oskit_stream_t *si, oskit_u64_t offset,
			   oskit_u64_t size, oskit_u32_t lock_type)
{
	return OSKIT_E_NOTIMPL;
}

static OSKIT_COMDECL
stat(oskit_stream_t *si, oskit_stream_stat_t *out_stat,
		  oskit_u32_t stat_flags)
{
	return OSKIT_E_NOTIMPL;	/*XXX*/
}

static OSKIT_COMDECL
clone(oskit_stream_t *si, oskit_stream_t **out_stream)
{
	return OSKIT_E_NOTIMPL;	/*XXX*/
}

struct oskit_stream_ops oskit_trivial_stream_ops = {
	query, add_ref, release,
	read, write, seek, setsize,
	copyto,
	commit, revert, lock_region, unlock_region, stat, clone
};