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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
export var ComposeUtils = {
loadBlockedImage,
};
/**
* Convert the blocked content to a data URL.
*
* @param {string} url - (necko) URL to unblock.
* @returns {string} the image as data: URL.
* @throws {Error} if reading the data failed.
*/
function loadBlockedImage(url) {
let filename;
if (/^(file|chrome|moz-extension):/i.test(url)) {
filename = url.split("/").at(-1);
} else {
const fnMatch = /[?&;]filename=([^?&]+)/.exec(url);
filename = fnMatch?.[1] || "";
}
filename = decodeURIComponent(filename);
const uri = Services.io.newURI(url);
let contentType;
if (filename) {
try {
contentType = Cc["@mozilla.org/mime;1"]
.getService(Ci.nsIMIMEService)
.getTypeFromURI(uri);
} catch (ex) {
contentType = "image/png";
}
if (!contentType.startsWith("image/")) {
// Unsafe to unblock this. It would just be garbage either way.
throw new Error(`Won't unblock; URL=${url}, contentType=${contentType}`);
}
} else {
// Assuming image/png is the best we can do.
contentType = "image/png";
}
const channel = Services.io.newChannelFromURI(
uri,
null,
Services.scriptSecurityManager.getSystemPrincipal(),
null,
Ci.nsILoadInfo.SEC_ALLOW_CROSS_ORIGIN_SEC_CONTEXT_IS_NULL,
Ci.nsIContentPolicy.TYPE_OTHER
);
const inputStream = channel.open();
const stream = Cc["@mozilla.org/binaryinputstream;1"].createInstance(
Ci.nsIBinaryInputStream
);
stream.setInputStream(inputStream);
let streamData = "";
try {
while (stream.available() > 0) {
streamData += stream.readBytes(stream.available());
}
} catch (e) {
stream.close();
throw new Error(`Couldn't read all data from URL=${url}`, { cause: e });
}
stream.close();
const encoded = btoa(streamData);
const dataURL =
"data:" +
contentType +
(filename ? ";filename=" + encodeURIComponent(filename) : "") +
";base64," +
encoded;
return dataURL;
}