86 lines
2.2 KiB
JavaScript
86 lines
2.2 KiB
JavaScript
var hpack = require('../hpack');
|
|
var utils = hpack.utils;
|
|
var assert = utils.assert;
|
|
|
|
function Table(options) {
|
|
this['static'] = hpack['static-table'];
|
|
this.dynamic = [];
|
|
this.size = 0;
|
|
this.maxSize = 0;
|
|
this.length = this['static'].table.length;
|
|
this.protocolMaxSize = options.maxSize;
|
|
this.maxSize = this.protocolMaxSize;
|
|
this.lookupDepth = options.lookupDepth || 32;
|
|
}
|
|
module.exports = Table;
|
|
|
|
Table.create = function create(options) {
|
|
return new Table(options);
|
|
};
|
|
|
|
Table.prototype.lookup = function lookup(index) {
|
|
assert(index !== 0, 'Zero indexed field');
|
|
assert(index <= this.length, 'Indexed field OOB')
|
|
|
|
if (index <= this['static'].table.length)
|
|
return this['static'].table[index - 1];
|
|
else
|
|
return this.dynamic[this.length - index];
|
|
};
|
|
|
|
Table.prototype.reverseLookup = function reverseLookup(name, value) {
|
|
var staticEntry = this['static'].map[name];
|
|
if (staticEntry && staticEntry.values[value])
|
|
return staticEntry.values[value];
|
|
|
|
// Reverse search dynamic table (new items are at the end of it)
|
|
var limit = Math.max(0, this.dynamic.length - this.lookupDepth);
|
|
for (var i = this.dynamic.length - 1; i >= limit; i--) {
|
|
var entry = this.dynamic[i];
|
|
if (entry.name === name && entry.value === value)
|
|
return this.length - i;
|
|
|
|
if (entry.name === name) {
|
|
// Prefer smaller index
|
|
if (staticEntry)
|
|
break;
|
|
return -(this.length - i);
|
|
}
|
|
}
|
|
|
|
if (staticEntry)
|
|
return -staticEntry.index;
|
|
|
|
return 0;
|
|
};
|
|
|
|
Table.prototype.add = function add(name, value, nameSize, valueSize) {
|
|
var totalSize = nameSize + valueSize + 32;
|
|
|
|
this.dynamic.push({
|
|
name: name,
|
|
value: value,
|
|
nameSize: nameSize,
|
|
totalSize: totalSize
|
|
});
|
|
this.size += totalSize;
|
|
this.length++;
|
|
|
|
this.evict();
|
|
};
|
|
|
|
Table.prototype.evict = function evict() {
|
|
while (this.size > this.maxSize) {
|
|
var entry = this.dynamic.shift();
|
|
this.size -= entry.totalSize;
|
|
this.length--;
|
|
}
|
|
assert(this.size >= 0, 'Table size sanity check failed');
|
|
};
|
|
|
|
Table.prototype.updateSize = function updateSize(size) {
|
|
assert(size <= this.protocolMaxSize, 'Table size bigger than maximum');
|
|
this.maxSize = size;
|
|
this.evict();
|
|
};
|