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/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*-
* 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
/**
* Native Android logging for JavaScript. Lets you specify a priority and tag
* in addition to the message being logged. Resembles the android.util.Log API
*
* // Import it as a ESM:
* let Log =
* .AndroidLog;
*
* // Use Log.i, Log.v, Log.d, Log.w, and Log.e to log verbose, debug, info,
* // warning, and error messages, respectively.
* Log.v("MyModule", "This is a verbose message.");
* Log.d("MyModule", "This is a debug message.");
* Log.i("MyModule", "This is an info message.");
* Log.w("MyModule", "This is a warning message.");
* Log.e("MyModule", "This is an error message.");
*
* // Bind a function with a tag to replace a bespoke dump/log/debug function:
* let debug = Log.d.bind(null, "MyModule");
* debug("This is a debug message.");
* // Outputs "D/GeckoMyModule(#####): This is a debug message."
*
* // Or "bind" the module object to a tag to automatically tag messages:
* Log = Log.bind("MyModule");
* Log.d("This is a debug message.");
* // Outputs "D/GeckoMyModule(#####): This is a debug message."
*
* Note: the module automatically prepends "Gecko" to the tag you specify,
* since all tags used by Fennec code should start with that string; and it
* truncates tags longer than MAX_TAG_LENGTH characters (not including "Gecko").
*/
const ANDROID_LOG_VERBOSE = 2;
const ANDROID_LOG_DEBUG = 3;
const ANDROID_LOG_INFO = 4;
const ANDROID_LOG_WARN = 5;
const ANDROID_LOG_ERROR = 6;
// android.util.Log.isLoggable throws IllegalArgumentException if a tag length
// exceeds 23 characters, and we prepend five characters ("Gecko") to every tag.
// However, __android_log_write itself and other android.util.Log methods don't
// seem to mind longer tags.
const MAX_TAG_LENGTH = 18;
var liblog = ctypes.open("liblog.so"); // /system/lib/liblog.so
var __android_log_write = liblog.declare(
"__android_log_write",
ctypes.default_abi,
ctypes.int, // return value: num bytes logged
ctypes.int, // priority (ANDROID_LOG_* constant)
ctypes.char.ptr, // tag
ctypes.char.ptr
); // message
export var AndroidLog = {
MAX_TAG_LENGTH,
v: (tag, msg) => __android_log_write(ANDROID_LOG_VERBOSE, "Gecko" + tag, msg),
d: (tag, msg) => __android_log_write(ANDROID_LOG_DEBUG, "Gecko" + tag, msg),
i: (tag, msg) => __android_log_write(ANDROID_LOG_INFO, "Gecko" + tag, msg),
w: (tag, msg) => __android_log_write(ANDROID_LOG_WARN, "Gecko" + tag, msg),
e: (tag, msg) => __android_log_write(ANDROID_LOG_ERROR, "Gecko" + tag, msg),
bind(tag) {
return {
MAX_TAG_LENGTH,
v: AndroidLog.v.bind(null, tag),
d: AndroidLog.d.bind(null, tag),
i: AndroidLog.i.bind(null, tag),
w: AndroidLog.w.bind(null, tag),
e: AndroidLog.e.bind(null, tag),
};
},
};