1 files changed, 100 insertions, 0 deletions
diff --git a/HttpRequestHeaders.jsm b/HttpRequestHeaders.jsm
new file mode 100644
index 0000000..c2b0bcd
--- /dev/null
+++ b/HttpRequestHeaders.jsm
@@ -0,0 +1,100 @@
+/*******************************************************************************
+
+    ηMatrix - a browser extension to black/white list requests.
+    Copyright (C) 2014-2019 The uMatrix/uBlock Origin authors
+    Copyright (C) 2019 Alessio Vanni
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see {http://www.gnu.org/licenses/}.
+
+    Home: https://gitlab.com/vannilla/ematrix
+    uMatrix Home: https://github.com/gorhill/uMatrix
+*/
+
+var EXPORTED_SYMBOLS = ['HTTPRequestHeaders'];
+
+var junkyard = [];
+
+let HTTPRequestHeaders = function (channel) {
+    this.init(channel);
+};
+
+HTTPRequestHeaders.factory = function (channel) {
+    let entry = junkyard.pop();
+    if (entry) {
+	return entry.init(channel);
+    }
+
+    return new HTTPRequestHeaders(channel);
+}
+
+HTTPRequestHeaders.prototype.init = function (channel) {
+    this.channel = channel;
+    this.headers = new Array();
+    this.originalHeaderNames = new Array();
+    
+    channel.visitRequestHeaders({
+	visitHeader: function (name, value) {
+	    this.headers.push({name: name, value: value});
+	    this.originalHeaderNames.push(name);
+	}.bind(this)
+    });
+    
+    return this;
+};
+
+HTTPRequestHeaders.prototype.dispose = function () {
+    this.channel = null;
+    this.headers = null;
+    this.originalHeaderNames = null;
+    junkyard.push(this);
+};
+
+HTTPRequestHeaders.prototype.update = function () {
+    let newHeaderNames = new Set();
+    for (let header of this.headers) {
+        this.setHeader(header.name, header.value, true);
+        newHeaderNames.add(header.name);
+    }
+    
+    //Clear any headers that were removed
+    for (let name of this.originalHeaderNames) {
+        if (!newHeaderNames.has(name)) {
+	    this.channel.setRequestHeader(name, '', false);
+        }
+    }
+};
+
+HTTPRequestHeaders.prototype.getHeader = function (name) {
+    try {
+        return this.channel.getRequestHeader(name);
+    } catch (e) {
+	// Ignore
+    }
+    
+    return '';
+};
+
+HTTPRequestHeaders.prototype.setHeader = function (name, newValue, create) {
+    let oldValue = this.getHeader(name);
+    if (newValue === oldValue) {
+        return false;
+    }
+    
+    if (oldValue === '' && create !== true) {
+        return false;
+    }
+    
+    this.channel.setRequestHeader(name, newValue, false);
+    return true;
+};