gecko-dev/toolkit/devtools/server/actors/call-watcher.js

697 lines
21 KiB
JavaScript

/* 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
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
"use strict";
const {Cc, Ci, Cu, Cr} = require("chrome");
const events = require("sdk/event/core");
const {Promise: promise} = Cu.import("resource://gre/modules/Promise.jsm", {});
const protocol = require("devtools/server/protocol");
const {ContentObserver} = require("devtools/content-observer");
const {on, once, off, emit} = events;
const {method, Arg, Option, RetVal} = protocol;
exports.register = function(handle) {
handle.addTabActor(CallWatcherActor, "callWatcherActor");
};
exports.unregister = function(handle) {
handle.removeTabActor(CallWatcherActor);
};
/**
* Type describing a single function call in a stack trace.
*/
protocol.types.addDictType("call-stack-item", {
name: "string",
file: "string",
line: "number"
});
/**
* Type describing an overview of a function call.
*/
protocol.types.addDictType("call-details", {
type: "number",
name: "string",
stack: "array:call-stack-item"
});
/**
* This actor contains information about a function call, like the function
* type, name, stack, arguments, returned value etc.
*/
let FunctionCallActor = protocol.ActorClass({
typeName: "function-call",
/**
* Creates the function call actor.
*
* @param DebuggerServerConnection conn
* The server connection.
* @param DOMWindow window
* The content window.
* @param string global
* The name of the global object owning this function, like
* "CanvasRenderingContext2D" or "WebGLRenderingContext".
* @param object caller
* The object owning the function when it was called.
* For example, in `foo.bar()`, the caller is `foo`.
* @param number type
* Either METHOD_FUNCTION, METHOD_GETTER or METHOD_SETTER.
* @param string name
* The called function's name.
* @param array stack
* The called function's stack, as a list of { name, file, line } objects.
* @param array args
* The called function's arguments.
* @param any result
* The value returned by the function call.
* @param boolean holdWeak
* Determines whether or not FunctionCallActor stores a weak reference
* to the underlying objects.
*/
initialize: function(conn, [window, global, caller, type, name, stack, args, result], holdWeak) {
protocol.Actor.prototype.initialize.call(this, conn);
this.details = {
type: type,
name: name,
stack: stack,
};
// Store a weak reference to all objects so we don't
// prevent natural GC if `holdWeak` was passed into
// setup as truthy. Used in the Web Audio Editor.
if (holdWeak) {
let weakRefs = {
window: Cu.getWeakReference(window),
caller: Cu.getWeakReference(caller),
result: Cu.getWeakReference(result),
args: Cu.getWeakReference(args)
};
Object.defineProperties(this.details, {
window: { get: () => weakRefs.window.get() },
caller: { get: () => weakRefs.caller.get() },
result: { get: () => weakRefs.result.get() },
args: { get: () => weakRefs.args.get() }
});
}
// Otherwise, hold strong references to the objects.
else {
this.details.window = window;
this.details.caller = caller;
this.details.result = result;
this.details.args = args;
}
this.meta = {
global: -1,
previews: { caller: "", args: "" }
};
if (global == "WebGLRenderingContext") {
this.meta.global = CallWatcherFront.CANVAS_WEBGL_CONTEXT;
} else if (global == "CanvasRenderingContext2D") {
this.meta.global = CallWatcherFront.CANVAS_2D_CONTEXT;
} else if (global == "window") {
this.meta.global = CallWatcherFront.UNKNOWN_SCOPE;
} else {
this.meta.global = CallWatcherFront.GLOBAL_SCOPE;
}
this.meta.previews.caller = this._generateCallerPreview();
this.meta.previews.args = this._generateArgsPreview();
},
/**
* Customize the marshalling of this actor to provide some generic information
* directly on the Front instance.
*/
form: function() {
return {
actor: this.actorID,
type: this.details.type,
name: this.details.name,
file: this.details.stack[0].file,
line: this.details.stack[0].line,
callerPreview: this.meta.previews.caller,
argsPreview: this.meta.previews.args
};
},
/**
* Gets more information about this function call, which is not necessarily
* available on the Front instance.
*/
getDetails: method(function() {
let { type, name, stack } = this.details;
// Since not all calls on the stack have corresponding owner files (e.g.
// callbacks of a requestAnimationFrame etc.), there's no benefit in
// returning them, as the user can't jump to the Debugger from them.
for (let i = stack.length - 1;;) {
if (stack[i].file) {
break;
}
stack.pop();
i--;
}
// XXX: Use grips for objects and serialize them properly, in order
// to add the function's caller, arguments and return value. Bug 978957.
return {
type: type,
name: name,
stack: stack
};
}, {
response: { info: RetVal("call-details") }
}),
/**
* Serializes the caller's name so that it can be easily be transferred
* as a string, but still be useful when displayed in a potential UI.
*
* @return string
* The caller's name as a string.
*/
_generateCallerPreview: function() {
let global = this.meta.global;
if (global == CallWatcherFront.CANVAS_WEBGL_CONTEXT) {
return "gl";
}
if (global == CallWatcherFront.CANVAS_2D_CONTEXT) {
return "ctx";
}
return "";
},
/**
* Serializes the arguments so that they can be easily be transferred
* as a string, but still be useful when displayed in a potential UI.
*
* @return string
* The arguments as a string.
*/
_generateArgsPreview: function() {
let { caller, args, name } = this.details;
let { global } = this.meta;
// Get method signature to determine if there are any enums
// used in this method.
let enumArgs = (CallWatcherFront.ENUM_METHODS[global] || {})[name];
if (typeof enumArgs === "function") {
enumArgs = enumArgs(args);
}
// XXX: All of this sucks. Make this smarter, so that the frontend
// can inspect each argument, be it object or primitive. Bug 978960.
let serializeArgs = () => args.map((arg, i) => {
if (arg === undefined) {
return "undefined";
}
if (arg === null) {
return "null";
}
if (typeof arg == "function") {
return "Function";
}
if (typeof arg == "object") {
return "Object";
}
// If this argument matches the method's signature
// and is an enum, change it to its constant name.
if (enumArgs && enumArgs.indexOf(i) !== -1) {
return getBitToEnumValue(global, caller, arg);
}
return arg;
});
return serializeArgs().join(", ");
}
});
/**
* The corresponding Front object for the FunctionCallActor.
*/
let FunctionCallFront = protocol.FrontClass(FunctionCallActor, {
initialize: function(client, form) {
protocol.Front.prototype.initialize.call(this, client, form);
},
/**
* Adds some generic information directly to this instance,
* to avoid extra roundtrips.
*/
form: function(form) {
this.actorID = form.actor;
this.type = form.type;
this.name = form.name;
this.file = form.file;
this.line = form.line;
this.callerPreview = form.callerPreview;
this.argsPreview = form.argsPreview;
}
});
/**
* This actor observes function calls on certain objects or globals.
*/
let CallWatcherActor = exports.CallWatcherActor = protocol.ActorClass({
typeName: "call-watcher",
initialize: function(conn, tabActor) {
protocol.Actor.prototype.initialize.call(this, conn);
this.tabActor = tabActor;
this._onGlobalCreated = this._onGlobalCreated.bind(this);
this._onGlobalDestroyed = this._onGlobalDestroyed.bind(this);
this._onContentFunctionCall = this._onContentFunctionCall.bind(this);
},
destroy: function(conn) {
protocol.Actor.prototype.destroy.call(this, conn);
this.finalize();
},
/**
* Starts waiting for the current tab actor's document global to be
* created, in order to instrument the specified objects and become
* aware of everything the content does with them.
*/
setup: method(function({ tracedGlobals, tracedFunctions, startRecording, performReload, holdWeak, storeCalls }) {
if (this._initialized) {
return;
}
this._initialized = true;
this._functionCalls = [];
this._tracedGlobals = tracedGlobals || [];
this._tracedFunctions = tracedFunctions || [];
this._holdWeak = !!holdWeak;
this._storeCalls = !!storeCalls;
this._contentObserver = new ContentObserver(this.tabActor);
on(this._contentObserver, "global-created", this._onGlobalCreated);
on(this._contentObserver, "global-destroyed", this._onGlobalDestroyed);
if (startRecording) {
this.resumeRecording();
}
if (performReload) {
this.tabActor.window.location.reload();
}
}, {
request: {
tracedGlobals: Option(0, "nullable:array:string"),
tracedFunctions: Option(0, "nullable:array:string"),
startRecording: Option(0, "boolean"),
performReload: Option(0, "boolean"),
holdWeak: Option(0, "boolean"),
storeCalls: Option(0, "boolean")
},
oneway: true
}),
/**
* Stops listening for document global changes and puts this actor
* to hibernation. This method is called automatically just before the
* actor is destroyed.
*/
finalize: method(function() {
if (!this._initialized) {
return;
}
this._initialized = false;
this._finalized = true;
this._contentObserver.stopListening();
off(this._contentObserver, "global-created", this._onGlobalCreated);
off(this._contentObserver, "global-destroyed", this._onGlobalDestroyed);
this._tracedGlobals = null;
this._tracedFunctions = null;
this._contentObserver = null;
}, {
oneway: true
}),
/**
* Returns whether the instrumented function calls are currently recorded.
*/
isRecording: method(function() {
return this._recording;
}, {
response: RetVal("boolean")
}),
/**
* Starts recording function calls.
*/
resumeRecording: method(function() {
this._recording = true;
}),
/**
* Stops recording function calls.
*/
pauseRecording: method(function() {
this._recording = false;
return this._functionCalls;
}, {
response: { calls: RetVal("array:function-call") }
}),
/**
* Erases all the recorded function calls.
* Calling `resumeRecording` or `pauseRecording` does not erase history.
*/
eraseRecording: method(function() {
this._functionCalls = [];
}),
/**
* Lightweight listener invoked whenever an instrumented function is called
* while recording. We're doing this to avoid the event emitter overhead,
* since this is expected to be a very hot function.
*/
onCall: function() {},
/**
* Invoked whenever the current tab actor's document global is created.
*/
_onGlobalCreated: function(window) {
let self = this;
this._tracedWindowId = ContentObserver.GetInnerWindowID(window);
let unwrappedWindow = XPCNativeWrapper.unwrap(window);
let callback = this._onContentFunctionCall;
for (let global of this._tracedGlobals) {
let prototype = unwrappedWindow[global].prototype;
let properties = Object.keys(prototype);
properties.forEach(name => overrideSymbol(global, prototype, name, callback));
}
for (let name of this._tracedFunctions) {
overrideSymbol("window", unwrappedWindow, name, callback);
}
/**
* Instruments a method, getter or setter on the specified target object to
* invoke a callback whenever it is called.
*/
function overrideSymbol(global, target, name, callback) {
let propertyDescriptor = Object.getOwnPropertyDescriptor(target, name);
if (propertyDescriptor.get || propertyDescriptor.set) {
overrideAccessor(global, target, name, propertyDescriptor, callback);
return;
}
if (propertyDescriptor.writable && typeof propertyDescriptor.value == "function") {
overrideFunction(global, target, name, propertyDescriptor, callback);
return;
}
}
/**
* Instruments a function on the specified target object.
*/
function overrideFunction(global, target, name, descriptor, callback) {
let originalFunc = target[name];
Object.defineProperty(target, name, {
value: function(...args) {
let result = originalFunc.apply(this, args);
if (self._recording) {
let stack = getStack(name);
let type = CallWatcherFront.METHOD_FUNCTION;
callback(unwrappedWindow, global, this, type, name, stack, args, result);
}
return result;
},
configurable: descriptor.configurable,
enumerable: descriptor.enumerable,
writable: true
});
}
/**
* Instruments a getter or setter on the specified target object.
*/
function overrideAccessor(global, target, name, descriptor, callback) {
let originalGetter = target.__lookupGetter__(name);
let originalSetter = target.__lookupSetter__(name);
Object.defineProperty(target, name, {
get: function(...args) {
if (!originalGetter) return undefined;
let result = originalGetter.apply(this, args);
if (self._recording) {
let stack = getStack(name);
let type = CallWatcherFront.GETTER_FUNCTION;
callback(unwrappedWindow, global, this, type, name, stack, args, result);
}
return result;
},
set: function(...args) {
if (!originalSetter) return;
originalSetter.apply(this, args);
if (self._recording) {
let stack = getStack(name);
let type = CallWatcherFront.SETTER_FUNCTION;
callback(unwrappedWindow, global, this, type, name, stack, args, undefined);
}
},
configurable: descriptor.configurable,
enumerable: descriptor.enumerable
});
}
/**
* Stores the relevant information about calls on the stack when
* a function is called.
*/
function getStack(caller) {
try {
// Using Components.stack wouldn't be a better idea, since it's
// much slower because it attempts to retrieve the C++ stack as well.
throw new Error();
} catch (e) {
var stack = e.stack;
}
// Of course, using a simple regex like /(.*?)@(.*):(\d*):\d*/ would be
// much prettier, but this is a very hot function, so let's sqeeze
// every drop of performance out of it.
let calls = [];
let callIndex = 0;
let currNewLinePivot = stack.indexOf("\n") + 1;
let nextNewLinePivot = stack.indexOf("\n", currNewLinePivot);
while (nextNewLinePivot > 0) {
let nameDelimiterIndex = stack.indexOf("@", currNewLinePivot);
let columnDelimiterIndex = stack.lastIndexOf(":", nextNewLinePivot - 1);
let lineDelimiterIndex = stack.lastIndexOf(":", columnDelimiterIndex - 1);
if (!calls[callIndex]) {
calls[callIndex] = { name: "", file: "", line: 0 };
}
if (!calls[callIndex + 1]) {
calls[callIndex + 1] = { name: "", file: "", line: 0 };
}
if (callIndex > 0) {
let file = stack.substring(nameDelimiterIndex + 1, lineDelimiterIndex);
let line = stack.substring(lineDelimiterIndex + 1, columnDelimiterIndex);
let name = stack.substring(currNewLinePivot, nameDelimiterIndex);
calls[callIndex].name = name;
calls[callIndex - 1].file = file;
calls[callIndex - 1].line = line;
} else {
// Since the topmost stack frame is actually our overwritten function,
// it will not have the expected name.
calls[0].name = caller;
}
currNewLinePivot = nextNewLinePivot + 1;
nextNewLinePivot = stack.indexOf("\n", currNewLinePivot);
callIndex++;
}
return calls;
}
},
/**
* Invoked whenever the current tab actor's inner window is destroyed.
*/
_onGlobalDestroyed: function(id) {
if (this._tracedWindowId == id) {
this.pauseRecording();
this.eraseRecording();
}
},
/**
* Invoked whenever an instrumented function is called.
*/
_onContentFunctionCall: function(...details) {
// If the consuming tool has finalized call-watcher, ignore the
// still-instrumented calls.
if (this._finalized) {
return;
}
let functionCall = new FunctionCallActor(this.conn, details, this._holdWeak);
if (this._storeCalls) {
this._functionCalls.push(functionCall);
}
this.onCall(functionCall);
}
});
/**
* The corresponding Front object for the CallWatcherActor.
*/
let CallWatcherFront = exports.CallWatcherFront = protocol.FrontClass(CallWatcherActor, {
initialize: function(client, { callWatcherActor }) {
protocol.Front.prototype.initialize.call(this, client, { actor: callWatcherActor });
this.manage(this);
}
});
/**
* Constants.
*/
CallWatcherFront.METHOD_FUNCTION = 0;
CallWatcherFront.GETTER_FUNCTION = 1;
CallWatcherFront.SETTER_FUNCTION = 2;
CallWatcherFront.GLOBAL_SCOPE = 0;
CallWatcherFront.UNKNOWN_SCOPE = 1;
CallWatcherFront.CANVAS_WEBGL_CONTEXT = 2;
CallWatcherFront.CANVAS_2D_CONTEXT = 3;
CallWatcherFront.ENUM_METHODS = {};
CallWatcherFront.ENUM_METHODS[CallWatcherFront.CANVAS_2D_CONTEXT] = {
asyncDrawXULElement: [6],
drawWindow: [6]
};
CallWatcherFront.ENUM_METHODS[CallWatcherFront.CANVAS_WEBGL_CONTEXT] = {
activeTexture: [0],
bindBuffer: [0],
bindFramebuffer: [0],
bindRenderbuffer: [0],
bindTexture: [0],
blendEquation: [0],
blendEquationSeparate: [0, 1],
blendFunc: [0, 1],
blendFuncSeparate: [0, 1, 2, 3],
bufferData: [0, 1, 2],
bufferSubData: [0, 1],
checkFramebufferStatus: [0],
clear: [0],
compressedTexImage2D: [0, 2],
compressedTexSubImage2D: [0, 6],
copyTexImage2D: [0, 2],
copyTexSubImage2D: [0],
createShader: [0],
cullFace: [0],
depthFunc: [0],
disable: [0],
drawArrays: [0],
drawElements: [0, 2],
enable: [0],
framebufferRenderbuffer: [0, 1, 2],
framebufferTexture2D: [0, 1, 2],
frontFace: [0],
generateMipmap: [0],
getBufferParameter: [0, 1],
getParameter: [0],
getFramebufferAttachmentParameter: [0, 1, 2],
getProgramParameter: [1],
getRenderbufferParameter: [0, 1],
getShaderParameter: [1],
getShaderPrecisionFormat: [0, 1],
getTexParameter: [0, 1],
getVertexAttrib: [1],
getVertexAttribOffset: [1],
hint: [0, 1],
isEnabled: [0],
pixelStorei: [0],
readPixels: [4, 5],
renderbufferStorage: [0, 1],
stencilFunc: [0],
stencilFuncSeparate: [0, 1],
stencilMaskSeparate: [0],
stencilOp: [0, 1, 2],
stencilOpSeparate: [0, 1, 2, 3],
texImage2D: (args) => args.length > 6 ? [0, 2, 6, 7] : [0, 2, 3, 4],
texParameterf: [0, 1],
texParameteri: [0, 1, 2],
texSubImage2D: (args) => args.length === 9 ? [0, 6, 7] : [0, 4, 5],
vertexAttribPointer: [2]
};
/**
* A lookup table for cross-referencing flags or properties with their name
* assuming they look LIKE_THIS most of the time.
*
* For example, when gl.clear(gl.COLOR_BUFFER_BIT) is called, the actual passed
* argument's value is 16384, which we want identified as "COLOR_BUFFER_BIT".
*/
var gEnumRegex = /^[A-Z][A-Z0-9_]+$/;
var gEnumsLookupTable = {};
// These values are returned from errors, or empty values,
// and need to be ignored when checking arguments due to the bitwise math.
var INVALID_ENUMS = [
"INVALID_ENUM", "NO_ERROR", "INVALID_VALUE", "OUT_OF_MEMORY", "NONE"
];
function getBitToEnumValue(type, object, arg) {
let table = gEnumsLookupTable[type];
// If mapping not yet created, do it on the first run.
if (!table) {
table = gEnumsLookupTable[type] = {};
for (let key in object) {
if (key.match(gEnumRegex)) {
// Maps `16384` to `"COLOR_BUFFER_BIT"`, etc.
table[object[key]] = key;
}
}
}
// If a single bit value, just return it.
if (table[arg]) {
return table[arg];
}
// Otherwise, attempt to reduce it to the original bit flags:
// `16640` -> "COLOR_BUFFER_BIT | DEPTH_BUFFER_BIT"
let flags = [];
for (let flag in table) {
if (INVALID_ENUMS.indexOf(table[flag]) !== -1) {
continue;
}
// Cast to integer as all values are stored as strings
// in `table`
flag = flag | 0;
if (flag && (arg & flag) === flag) {
flags.push(table[flag]);
}
}
// Cache the combined bitmask value
return table[arg] = flags.join(" | ") || arg;
}