mfc_inst_pool.c

来自「6410BSP3」· C语言 代码 · 共 102 行

//
// Copyright (c) Samsung Electronics. Co. LTD.  All rights reserved.
//
/*++
THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF
ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO
THE IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A
PARTICULAR PURPOSE.

*/


#include "MfcConfig.h"
#include "MFC_Inst_Pool.h"

#if !defined(MFC_NUM_INSTANCES_MAX)
#error "MFC_NUM_INSTANCES_MAX should be defined."
#endif
#if ((MFC_NUM_INSTANCES_MAX <= 0) || (MFC_NUM_INSTANCES_MAX > 8))
    #error "MFC_NUM_INSTANCES_MAX should be in the range of 1 ~ 8."
#endif



static int _inst_no = 0;
static int _inst_status[MFC_NUM_INSTANCES_MAX] = {0, };
static int _num_inst_avail = MFC_NUM_INSTANCES_MAX;


int MfcInstPool_NumAvail(void)
{
    return _num_inst_avail;
}


int MfcInstPool_Occupy(void)
{
    int  i;

    if (_num_inst_avail == 0)
        return -1;

    for (i=0; i<MFC_NUM_INSTANCES_MAX; i++) {
        if (_inst_status[_inst_no] == 0) {
            _num_inst_avail--;
            _inst_status[_inst_no] = 1;
            return _inst_no;
        }

        _inst_no = (_inst_no + 1) % MFC_NUM_INSTANCES_MAX;
    }

    return -1;
}


int MfcInstPool_Release(int instance_no)
{
    if (instance_no >= MFC_NUM_INSTANCES_MAX || instance_no < 0) {
        return -1;
    }

    if (_inst_status[instance_no] == 0)
        return -1;

    _num_inst_avail++;
    _inst_status[instance_no] = 0;

    return instance_no;
}


void MfcInstPool_OccupyAll(void)
{
    int  i;

    if (_num_inst_avail == 0)
        return;

    for (i=0; i<MFC_NUM_INSTANCES_MAX; i++) {
        if (_inst_status[i] == 0) {
            _num_inst_avail--;
            _inst_status[i] = 1;
        }
    }
}

void MfcInstPool_ReleaseAll(void)
{
    int  i;

    if (_num_inst_avail == MFC_NUM_INSTANCES_MAX)
        return;

    for (i=0; i<MFC_NUM_INSTANCES_MAX; i++) {
        if (_inst_status[i] == 1) {
            _num_inst_avail++;
            _inst_status[i] = 0;
        }
    }
}