px4-firmware/misc/pascal/insn16/libinsn/pgetopcode.c

141 lines
4.4 KiB
C

/**********************************************************************
* pgetopcode.c
* P-Code access utilities
*
* Copyright (C) 2008-2009 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
**********************************************************************/
/**********************************************************************
* Included Files
**********************************************************************/
#include <stdint.h>
#include "keywords.h"
#include "podefs.h"
#include "pinsn16.h"
#include "paslib.h"
#include "pofflib.h"
#include "pinsn.h"
/**********************************************************************
* Private Function Prototypes
**********************************************************************/
/**********************************************************************
* Global Variables
**********************************************************************/
static int16_t g_bEndIn = 0; /* 1 = oEND pcode or EOF received */
/**********************************************************************
* Private Variables
**********************************************************************/
/**********************************************************************
* Private Functions
**********************************************************************/
/**********************************************************************
* Global Functions
**********************************************************************/
/**********************************************************************/
uint32_t insn_GetOpCode(poffHandle_t handle, OPTYPE *ptr)
{
uint32_t opsize = 1;
int c;
TRACE(stderr, "[insn_GetOpCode]");
/* If we are not already at the EOF, read the next character from
* the input stream.
*/
if (!g_bEndIn)
c = poffGetProgByte(handle);
else
c = EOF;
/* Check for end of file. We may have previously parsed oEND which
* is a 'logical' end of file for a pascal program (but not a unit)
* or we may be at the physical end of the file wihout encountering
* oEND (typical for a UNIT file).
*/
if ((g_bEndIn) || (c == EOF))
{
ptr->op = oEND;
ptr->arg1 = 0;
ptr->arg2 = 0;
} /* end if */
else
{
ptr->op = c;
g_bEndIn = (ptr->op == oEND);
if (ptr->op & o8)
{
ptr->arg1 = poffGetProgByte(handle);
opsize++;
}
else
{
ptr->arg1 = 0;
}
if (ptr->op & o16)
{
ptr->arg2 = (poffGetProgByte(handle) << 8);
ptr->arg2 |= (poffGetProgByte(handle) & 0xff);
opsize += 2;
}
else
{
ptr->arg2 = 0;
}
}
return opsize;
}
/**********************************************************************/
void insn_ResetOpCodeRead(poffHandle_t handle)
{
poffResetAccess(handle);
g_bEndIn = 0;
}
/***********************************************************************/