direct_console.c

基于组件方式开发操作系统的OSKIT源代码

/*
 * 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 [e-mail] or [phone].
 * 
 * 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 direct console
 */

#include <oskit/com/stream.h>
#include <oskit/arm32/shark/direct_cons.h>
#include <oskit/arm32/shark/direct_console.h>

struct strm {
	oskit_stream_t strmi;
	int refs;
};

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

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

	*out_ihandle = 0;
	return OSKIT_E_NOINTERFACE;
}

static OSKIT_COMDECL_U
add_ref(oskit_stream_t *si)
{
	struct strm *s = (struct strm*)si;

	return ++s->refs;
}

static OSKIT_COMDECL_U
release(oskit_stream_t *si)
{
	struct strm *s = (struct strm*)si;
	int newcount = --s->refs;

#if 0 /* And just how do we expect this to work? */
	if (newcount < 0)
		panic("direct_console: mangled reference count");
#endif
#if 0
	/* Statically allocated so don't free it */
	if (newcount == 0) {
		osenv_mem_free(s, 0, sizeof(*s));
	}
#endif
	return newcount;
}

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

	int i;
	for(i=0; i < len; ++i) {
		((char*)buf)[i] = direct_cons_getchar();
	}
	*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 strm *s = (struct strm*)si;

	int i=0;
	for(i=0; i < len; ++i) {
		direct_cons_putchar(((char*)buf)[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*/
}

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

/* 
 * This is exported in case anyone wants to use it before
 * calling direct_console_init.  This might be necessary at
 * boot time.
 *
 * Everyone outside this file should declare it as oskit_stream_t.  
 * Efforts to give it that type in this file failed miserably.
 */
struct strm boot_direct_console = {
	.strmi = { .ops = &ops },
	.refs  = 1
};  

oskit_error_t
direct_console_init(oskit_stream_t **out_stream)
{
	*out_stream = &boot_direct_console.strmi;
	return 0;
}