HeapSnapshotLoader.js [plain text]
WebInspector.HeapSnapshotLoader = function()
{
this._reset();
}
WebInspector.HeapSnapshotLoader.prototype = {
dispose: function()
{
this._reset();
},
_reset: function()
{
this._json = "";
this._state = "find-snapshot-info";
this._snapshot = {};
},
close: function()
{
if (this._json)
this._parseStringsArray();
},
buildSnapshot: function(constructorName)
{
var constructor = WebInspector[constructorName];
var result = new constructor(this._snapshot);
this._reset();
return result;
},
_parseUintArray: function()
{
var index = 0;
var char0 = "0".charCodeAt(0), char9 = "9".charCodeAt(0), closingBracket = "]".charCodeAt(0);
var length = this._json.length;
while (true) {
while (index < length) {
var code = this._json.charCodeAt(index);
if (char0 <= code && code <= char9)
break;
else if (code === closingBracket) {
this._json = this._json.slice(index + 1);
return false;
}
++index;
}
if (index === length) {
this._json = "";
return true;
}
var nextNumber = 0;
var startIndex = index;
while (index < length) {
var code = this._json.charCodeAt(index);
if (char0 > code || code > char9)
break;
nextNumber *= 10;
nextNumber += (code - char0);
++index;
}
if (index === length) {
this._json = this._json.slice(startIndex);
return true;
}
this._array[this._arrayIndex++] = nextNumber;
}
},
_parseStringsArray: function()
{
var closingBracketIndex = this._json.lastIndexOf("]");
if (closingBracketIndex === -1)
throw new Error("Incomplete JSON");
this._json = this._json.slice(0, closingBracketIndex + 1);
this._snapshot.strings = JSON.parse(this._json);
},
write: function(chunk)
{
this._json += chunk;
switch (this._state) {
case "find-snapshot-info": {
var snapshotToken = "\"snapshot\"";
var snapshotTokenIndex = this._json.indexOf(snapshotToken);
if (snapshotTokenIndex === -1)
throw new Error("Snapshot token not found");
this._json = this._json.slice(snapshotTokenIndex + snapshotToken.length + 1);
this._state = "parse-snapshot-info";
}
case "parse-snapshot-info": {
var closingBracketIndex = WebInspector.findBalancedCurlyBrackets(this._json);
if (closingBracketIndex === -1)
return;
this._snapshot.snapshot = (JSON.parse(this._json.slice(0, closingBracketIndex)));
this._json = this._json.slice(closingBracketIndex);
this._state = "find-nodes";
}
case "find-nodes": {
var nodesToken = "\"nodes\"";
var nodesTokenIndex = this._json.indexOf(nodesToken);
if (nodesTokenIndex === -1)
return;
var bracketIndex = this._json.indexOf("[", nodesTokenIndex);
if (bracketIndex === -1)
return;
this._json = this._json.slice(bracketIndex + 1);
var node_fields_count = this._snapshot.snapshot.meta.node_fields.length;
var nodes_length = this._snapshot.snapshot.node_count * node_fields_count;
this._array = new Uint32Array(nodes_length);
this._arrayIndex = 0;
this._state = "parse-nodes";
}
case "parse-nodes": {
if (this._parseUintArray())
return;
this._snapshot.nodes = this._array;
this._state = "find-edges";
this._array = null;
}
case "find-edges": {
var edgesToken = "\"edges\"";
var edgesTokenIndex = this._json.indexOf(edgesToken);
if (edgesTokenIndex === -1)
return;
var bracketIndex = this._json.indexOf("[", edgesTokenIndex);
if (bracketIndex === -1)
return;
this._json = this._json.slice(bracketIndex + 1);
var edge_fields_count = this._snapshot.snapshot.meta.edge_fields.length;
var edges_length = this._snapshot.snapshot.edge_count * edge_fields_count;
this._array = new Uint32Array(edges_length);
this._arrayIndex = 0;
this._state = "parse-edges";
}
case "parse-edges": {
if (this._parseUintArray())
return;
this._snapshot.edges = this._array;
this._array = null;
this._state = "find-strings";
}
case "find-strings": {
var stringsToken = "\"strings\"";
var stringsTokenIndex = this._json.indexOf(stringsToken);
if (stringsTokenIndex === -1)
return;
var bracketIndex = this._json.indexOf("[", stringsTokenIndex);
if (bracketIndex === -1)
return;
this._json = this._json.slice(bracketIndex);
this._state = "accumulate-strings";
break;
}
case "accumulate-strings":
break;
}
}
};