HTML
<!DOCTYPE html>
<html>
<head>
<title>Banker's Algorithm</title>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.2.0/jquery.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js"></script>
<link rel="stylesheet" type="text/css" href="https://stackpath.bootstrapcdn.com/bootstrap/4.5.0/css/bootstrap.min.css" />
<script type="text/javascript" src="banker.js"></script>
</head>
<body>
<nav class="navbar navbar-expand-lg navbar-dark bg-primary">
<a class="navbar-brand" href="../Index/index.html#bankers">Home</a>
<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarColor01" aria-controls="navbarColor01" aria-expanded="false" aria-label="Toggle navigation" style="">
<span class="navbar-toggler-icon"></span>
</button>
</nav>
<br>
<div class="container">
<div class="jumbotron">
<h1 class="display-3">Banker's Safety Algorithm</h1>
<p class="lead">Detection algorithm to avoid deadlock</p>
<hr class="my-4">
<p>Banker's Algorithm is a resource allocation and deadlock avoidance algorithm that tests for safety by simulating the allocation of predetermined maximum possible amounts of all resources, and then makes an "safe-state" check to test for possible deadlock conditions for all other pending activities, before deciding whether allocation should be allowed to continue.</p>
</div>
<div class="jumbotron">
<form name = "resource">
<div class = "form-group" style="margin-left:50px; float:left;">
<label>Number of Resource types:</label><input class="form-control" type="Number" onkeyup="BuildFormFields(parseInt(this.value, 10));" />
<div id="FormFields" style=""></div>
</div>
</form>
<form name = "Need">
<div class = "form-group" style="margin-left:50px;float:left;">
<label>Number of Processes:</label> <input class="form-control" type="Number" onkeyup="BuildFormFields2(y = parseInt(this.value, 10));" />
<div id="FormFields1"></div>
</div>
</form>
<form name = "Alloc">
<div class = "form-group" style="margin-left:50px;float:left;margin-top:60px;">
<div id="FormFields2"></div>
</div>
</form>
<table id="tab_need" class="table table-striped table-hover">
</table>
<table id="tab_alloc" class="table table-striped table-hover">
</table>
<ul id = "printing">
</ul>
</div>
<div class="panel-footer">
<button class="btn btn-primary btn-success" onclick="banker()">Run</button>
</div>
</div>
</body>
</html>
CSS
h1, h2{
text-align: center;
}
table, td {
border: 1px solid black;
}
th, td {
padding: 25px;
text-align: center;
}
ul {
font-family: Arial, Helvetica, sans-serif;
font-size: 30px;
}
.form-control {
width: 100%;
}
thead{
text-align: center;
}
.table{
width:80%;
margin-left: 150px;
}
JAVASCRIPT
var res,pro;
var resource;
function BuildFormFields($amount) // For Resorce allocation
{
res = $amount;
if(res<0)
alert("Invalid Inputs");
var
$container = document.getElementById('FormFields'),
$item, $field, $i;
$container.innerHTML = '';
for ($i = 0; $i < $amount; $i++) {
$item = document.createElement('div');
$item.style.margin = '10px';
$field = document.createElement('label');
$field.innerHTML = 'Resource '+$i;
$item.appendChild($field);
$field = document.createElement('input');
$field.name = 'Design[' + $i + ']';
$field.type = 'text';
$field.setAttribute("class","form-control");
$item.appendChild($field);
$container.appendChild($item);
}
}
function BuildFormFields2($amount) //For Allocation
{
pro = $amount;
if($amount<0)
alert("Invalid Inputs");
console.log(res);
var
$container = document.getElementById('FormFields1'),
$item, $field, $i;
$container.innerHTML = '';
for ($i = 0; $i < $amount; $i++) {
for($j = 0; $j < res; $j++)
{
$item = document.createElement('div');
$item.style.margin = '10px';
$field = document.createElement('label');
$field.innerHTML = 'Need for process '+$i+' Res: ' +$j;
$item.appendChild($field);
$field = document.createElement('input');
$field.name = 'Design[' + $i + ']';
$field.type = 'text';
$field.setAttribute("class","form-control");
$item.appendChild($field);
$container.appendChild($item);
}
}
BuildFormFields3($amount);
}
function BuildFormFields3($amount) //For Allocation
{
if($amount<0)
alert("Invalid Inputs");
console.log(res);
var
$container = document.getElementById('FormFields2'),
$item, $field, $i;
$container.innerHTML = '';
for ($i = 0; $i < $amount; $i++) {
for($j = 0; $j < res; $j++)
{
$item = document.createElement('div');
$item.style.margin = '10px';
$field = document.createElement('label');
$field.innerHTML = 'Allocation for process '+$i+' Res: ' +$j;
$item.appendChild($field);
$field = document.createElement('input');
$field.name = 'Design[' + $i + ']';
$field.type = 'text';
$field.setAttribute("class","form-control");
$item.appendChild($field);
$container.appendChild($item);
}
}
}
var y;
function banker()
{
var res_form = document.resource;
var resource = [];
for(var i = 1;i <= res; i++)
{
resource[i-1] = Number(res_form[i].value);
}
console.log(resource);
var form = document.Need;
var ned = [];
var i,j;
console.log("PRO: "+pro+"RES: "+res);
for(i = 1; i <= pro*res; i++)
{
ned[i-1] = Number(form[i].value);
}
var needy = [];
for(var i = 0; i<pro;i++)
{
needy[i] = [];
for(var j=0;j<res;j++)
{
needy[i][j] = ned[i*res+j];
}
}
console.log(ned);
console.log(needy);
var alloc_form = document.Alloc;
var alloc = [];
for(var i = 0; i < pro; i++)
{
alloc[i] = [];
for(var j = 0;j < res;j++)
{
alloc[i][j] = Number(alloc_form[i*res+j].value);
console.log(alloc[i][j]);
}
}
console.log(alloc);
var avail = [];
for(var i = 0; i < res; i++)
avail[i] = resource[i];
for(var i = 0; i < pro; i++)
{
for(var j = 0; j < res; j++)
{
avail[j] = avail[j] - alloc[i][j];
needy[i][j] = needy[i][j] - alloc[i][j];
}
}
console.log('avail: ' + avail);
//TABLE for NEED
var tab_need = document.getElementById("tab_need");
var row = tab_need.insertRow(0);
var cell = row.insertCell(0);
cell.innerHTML = "<b>Need</b>";
var pro_head = tab_need.insertRow(1);
var cell = pro_head.insertCell(0);
cell.innerHTML = "<b>Process</b>";
for(i=1;i<=res;i++)
{
cell = pro_head.insertCell(i);
cell.innerHTML = "<b>Res "+(i-1)+"</b>";
}
for(i=0;i<pro;i++)
{
var row = tab_need.insertRow(i+2);
var cell = row.insertCell(0);
cell.innerHTML = "<b>P"+i+"</b>";
for(j=0;j<res;j++)
{
var cell = row.insertCell(j+1);
cell.innerHTML = ned[res*i+j];
}
}
//TABLE for ALLOC
var tab_alloc = document.getElementById("tab_alloc");
var row = tab_alloc.insertRow(0);
var cell = row.insertCell(0);
cell.innerHTML = "<b>Allocation</b>";
var alloc_head = tab_alloc.insertRow(1);
var cell = alloc_head.insertCell(0);
cell.innerHTML = "<b>Process</b>";
for(i=1;i<=res;i++)
{
cell = alloc_head.insertCell(i);
cell.innerHTML = "<b>Res "+(i-1)+"</b>";
}
for(i=0;i<pro;i++)
{
var row = tab_alloc.insertRow(i+2);
var cell = row.insertCell(0);
cell.innerHTML = "<b>P"+i+"</b>";
for(j=0;j<res;j++)
{
var cell = row.insertCell(j+1);
cell.innerHTML = alloc[i][j];
}
}
var prints = document.getElementById("printing");
var i,j;
var exec = 0; //Number of executed processes
var ex = [0,0];
for(var i = 0; i < pro; i++)
{
ex[i] = 0;
}
var iter = 1;
while(1)
{
var exec1 = exec // exec1 is compared with exec at the end of the while loop to check for deadlock
var li = document.createElement("li");
li.appendChild(document.createTextNode("Iteration "+ iter));
prints.appendChild(li);
var ul1 = document.createElement("ul");
for (i = 0; i < pro; i++)
{
var flag = 0
if(ex[i] == 0)
{
var li = document.createElement("li");
li.appendChild(document.createTextNode("Process "+ i+": "));
ul1.append(li);
prints.appendChild(ul1);
var ul2 = document.createElement("ul");
for (var j = 0; j < res; j++)
{
if((avail[j]) < needy[i][j])
{
flag = 1;
break;
}
}
if(flag)
{
console.log("Process " + i + " doesn't have enough resources");
console.log("Need: " + needy[i]);
console.log("Current resources available: " + avail);
var li = document.createElement("li");
li.appendChild(document.createTextNode("Process " + i + " doesn't have enough resources"));
ul2.append(li);
ul1.append(ul2);
prints.appendChild(ul1);
var li = document.createElement("li");
li.appendChild(document.createTextNode("Need: " + needy[i]));
ul2.append(li);
ul1.append(ul2);
prints.appendChild(ul1);
var li = document.createElement("li");
li.appendChild(document.createTextNode("Avail: " + avail));
ul2.append(li);
ul1.append(ul2);
prints.appendChild(ul1);
}
else
{
exec = exec + 1
console.log("Process " + i + " has enough resources");
var li = document.createElement("li");
li.appendChild(document.createTextNode("Process " + i + " has enough resources"));
ul2.append(li);
ul1.append(ul2);
prints.appendChild(ul1);
ex[i] = 1;
for(var j = 0;j < res; j++)
{
avail[j] = avail[j] + alloc[i][j];
}
console.log("Current resources available: " + avail);
var li = document.createElement("li");
li.appendChild(document.createTextNode("Avail: " + avail));
ul2.append(li);
ul1.append(ul2);
prints.appendChild(ul1);
}
}
}
iter++;
if(exec1 == exec && exec != pro) // Checks for deadlock
{
console.log("Deadlock");
var li = document.createElement("li");
li.appendChild(document.createTextNode("Deadlock"));
prints.appendChild(li);
break;
}
if(exec == pro)
{
console.log("Safe State");
var li = document.createElement("li");
li.appendChild(document.createTextNode("Safe State"));
prints.appendChild(li);
break;
}
}
}
