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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
/**
* The IOpenWithLauncher api call protocol shared by the producer
* (ShellService.setAsDefault{PDF,Protocol}Handler) and the consumer
* (WindowsSetDefaultAppCmdHandler).
*
* ShellService arms a one-shot redirect before launching the OS "Open with"
* picker via IOpenWithLauncher; once the user picks Firefox, the OS relaunches
* Firefox with the same value and the command-line handler consumes it. This
* module owns that shared state (the pref shape and the matching rules).
*/
const lazy = {};
ChromeUtils.defineESModuleGetters(lazy, {
FileUtils: "resource://gre/modules/FileUtils.sys.mjs",
});
// This pref is an object { openWithArg, overrideUri, type } consumed by
// WindowsSetDefaultAppCmdHandler when the user picks a default (file type or
// protocol) using the IOpenWithLauncher API. It is reset anytime the dialog is
// used again, or when we intercept the OS reopening one of our openWithArgs.
export const SET_DEFAULT_REDIRECT_PREF =
"browser.shell.setDefaultApp.pendingRedirect";
export class WindowsSetDefaultRedirect {
// Supported default types to set using IOpenWithLauncher.
static TYPE = {
FILE: 1 << 0,
PROTOCOL: 1 << 1,
};
/**
* Stash a one-shot redirect for the IOpenWithLauncher call.
*
* @param {string} openWithArg
* The value handed to launchSetDefaultAppPicker, which the OS hands back as
* "-osint -url <openWithArg>" once the user picks a new default. Depending on
* type, this is either a file path on the system (file-type defaults) or a
* URL (protocol defaults).
* @param {?string} overrideUri
* URI spec to open when openWithArg comes back, or null to consume the relaunch
* and open nothing.
* @param {number} type
* One of WindowsSetDefaultRedirect.TYPE, identifying whether openWithArg is a
* file path or a URL.
*/
static arm(openWithArg, overrideUri, type) {
// Clear any stale object left by an older call.
Services.prefs.clearUserPref(SET_DEFAULT_REDIRECT_PREF);
Services.prefs.setStringPref(
SET_DEFAULT_REDIRECT_PREF,
JSON.stringify({ openWithArg, overrideUri: overrideUri ?? null, type })
);
}
/**
* Clear a pending redirect.
*/
static clear() {
Services.prefs.clearUserPref(SET_DEFAULT_REDIRECT_PREF);
}
/**
* If `arg` is the openWithArg stashed by the most recent
* launchSetDefaultAppPicker call, consume the one-shot redirect and return
* its `{ overrideUri }`, where overrideUri is a URI spec to open or null to
* just suppress the relaunch. Returns null when `arg` is unrelated to a
* pending attempt to set a default.
*
* @param {string} arg - The -url value the OS handed back.
* @returns {?{overrideUri: ?string}}
*/
static consume(arg) {
const state = this.#read();
if (!state || !this.#matches(state, arg)) {
return null;
}
Services.prefs.clearUserPref(SET_DEFAULT_REDIRECT_PREF);
return { overrideUri: state.overrideUri ?? null };
}
/**
* Read and validate the pending redirect stashed by arm().
*
* @returns {?{openWithArg: string, overrideUri: ?string, type: number}} The
* stored state, or null when the pref is unset, holds the wrong type, or is
* malformed JSON.
*/
static #read() {
let raw;
try {
raw = Services.prefs.getStringPref(SET_DEFAULT_REDIRECT_PREF, "");
} catch (e) {
return null;
}
if (!raw) {
return null;
}
try {
const state = JSON.parse(raw);
return state && typeof state.openWithArg === "string" ? state : null;
} catch (e) {
return null;
}
}
/**
* Checks if the -url value the OS handed back matches the stashed redirect.
*
* @param {{openWithArg: string, type: number}} state - The stashed redirect.
* @param {string} arg - The -url value from the OS relaunch.
* @returns {boolean}
*/
static #matches(state, arg) {
switch (state.type) {
case this.TYPE.PROTOCOL:
return state.openWithArg === arg;
case this.TYPE.FILE:
try {
return new lazy.FileUtils.File(state.openWithArg).equals(
new lazy.FileUtils.File(arg)
);
} catch (e) {
return false;
}
default:
return false;
}
}
}