gecko-dev/dom/system/gonk/systemlibs.js

202 строки
5.3 KiB
JavaScript

/* Copyright 2012 Mozilla Foundation and Mozilla contributors
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
if (!this.ctypes) {
// We're likely being loaded as a JSM.
this.EXPORTED_SYMBOLS = [ "libcutils", "netHelpers" ];
Components.utils.import("resource://gre/modules/ctypes.jsm");
}
const SYSTEM_PROPERTY_KEY_MAX = 32;
const SYSTEM_PROPERTY_VALUE_MAX = 92;
// We leave this as 'undefined' instead of setting it to 'false'. That
// way a file that includes us can have it defined already without us
// overriding the value here.
var DEBUG;
/**
* Expose some system-level functions.
*/
this.libcutils = (function() {
let lib;
try {
lib = ctypes.open("libcutils.so");
} catch(ex) {
// Return a fallback option in case libcutils.so isn't present (e.g.
// when building Firefox with MOZ_B2G_RIL.
if (DEBUG) {
dump("Could not load libcutils.so. Using fake propdb.\n");
}
let fake_propdb = Object.create(null);
return {
property_get: function(key, defaultValue) {
if (key in fake_propdb) {
return fake_propdb[key];
}
return defaultValue === undefined ? null : defaultValue;
},
property_set: function(key, value) {
fake_propdb[key] = value;
}
};
}
let c_property_get = lib.declare("property_get", ctypes.default_abi,
ctypes.int, // return value: length
ctypes.char.ptr, // key
ctypes.char.ptr, // value
ctypes.char.ptr); // default
let c_property_set = lib.declare("property_set", ctypes.default_abi,
ctypes.int, // return value: success
ctypes.char.ptr, // key
ctypes.char.ptr); // value
let c_value_buf = ctypes.char.array(SYSTEM_PROPERTY_VALUE_MAX)();
return {
/**
* Get a system property.
*
* @param key
* Name of the property
* @param defaultValue [optional]
* Default value to return if the property isn't set (default: null)
*/
property_get: function(key, defaultValue) {
if (defaultValue === undefined) {
defaultValue = null;
}
c_property_get(key, c_value_buf, defaultValue);
return c_value_buf.readString();
},
/**
* Set a system property
*
* @param key
* Name of the property
* @param value
* Value to set the property to.
*/
property_set: function(key, value) {
let rv = c_property_set(key, value);
if (rv) {
throw Error('libcutils.property_set("' + key + '", "' + value +
'") failed with error ' + rv);
}
}
};
})();
/**
* Helpers for conversions.
*/
this.netHelpers = {
/**
* Swap byte orders for 32-bit value
*/
swap32: function(n) {
return (((n >> 24) & 0xFF) << 0) |
(((n >> 16) & 0xFF) << 8) |
(((n >> 8) & 0xFF) << 16) |
(((n >> 0) & 0xFF) << 24);
},
/**
* Convert network byte order to host byte order
* Note: Assume that the system is little endian
*/
ntohl: function(n) {
return this.swap32(n);
},
/**
* Convert host byte order to network byte order
* Note: Assume that the system is little endian
*/
htonl: function(n) {
return this.swap32(n);
},
/**
* Convert integer representation of an IP address to the string
* representation.
*
* @param ip
* IP address in number format.
*/
ipToString: function(ip) {
return ((ip >> 0) & 0xFF) + "." +
((ip >> 8) & 0xFF) + "." +
((ip >> 16) & 0xFF) + "." +
((ip >> 24) & 0xFF);
},
/**
* Convert string representation of an IP address to the integer
* representation (network byte order).
*
* @param string
* String containing the IP address.
*/
stringToIP: function(string) {
if (!string) {
return null;
}
let ip = 0;
let start, end = -1;
for (let i = 0; i < 4; i++) {
start = end + 1;
end = string.indexOf(".", start);
if (end == -1) {
end = string.length;
}
let num = parseInt(string.slice(start, end), 10);
if (isNaN(num)) {
return null;
}
ip |= num << (i * 8);
}
return ip;
},
/**
* Make a subnet mask.
*/
makeMask: function(len) {
let mask = 0;
for (let i = 0; i < len; ++i) {
mask |= (0x80000000 >> i);
}
return this.ntohl(mask);
},
/**
* Get Mask length from given mask address
*/
getMaskLength: function(mask) {
let len = 0;
let netmask = this.ntohl(mask);
while (netmask & 0x80000000) {
len++;
netmask = netmask << 1;
}
return len;
}
};