commands/FBVisualizationCommands.py

#!/usr/bin/python

# Copyright (c) Facebook, Inc. and its affiliates. All Rights Reserved
#
# This source code is licensed under the MIT license found in the
# LICENSE file in the root directory of this source tree.

import errno
import os
import time

import fbchisellldbbase as fb
import fbchisellldbobjecthelpers as objectHelpers
import lldb


def lldbcommands():
    return [FBVisualizeCommand()]


def _showImage(commandForImage):
    imageDirectory = "/tmp/xcode_debug_images/"

    imageName = time.strftime("%Y-%m-%d-%H-%M-%S", time.gmtime()) + ".png"
    imagePath = imageDirectory + imageName

    try:
        os.makedirs(imageDirectory)
    except OSError as e:
        if e.errno == errno.EEXIST and os.path.isdir(imageDirectory):
            pass
        else:
            raise

    toPNG = "(id)UIImagePNGRepresentation((id){})".format(commandForImage)
    imageDataAddress = fb.evaluateExpressionValue(toPNG, tryAllThreads=True).GetValue()
    imageBytesStartAddress = fb.evaluateExpression(
        "(void *)[(id)" + imageDataAddress + " bytes]"
    )
    imageBytesLength = fb.evaluateExpression(
        "(NSUInteger)[(id)" + imageDataAddress + " length]"
    )

    address = int(imageBytesStartAddress, 16)
    length = int(imageBytesLength)

    if not (address or length):
        print("Could not get image data.")
        return

    process = lldb.debugger.GetSelectedTarget().GetProcess()
    error = lldb.SBError()
    mem = process.ReadMemory(address, length, error)

    if error is not None and str(error) != "success":
        print(error)
    else:
        with open(imagePath, "wb") as imgFile:
            imgFile.write(mem)
        os.system("open " + imagePath)


def _colorIsCGColorRef(color):
    color = "(CGColorRef)(" + color + ")"

    result = fb.evaluateExpressionValue(
        "(unsigned long)CFGetTypeID({color}) == (unsigned long)CGColorGetTypeID()".format(
            color=color
        )
    )

    if result.GetError() is not None and str(result.GetError()) != "success":
        print("got error: {}".format(result))
        return False
    else:
        isCFColor = result.GetValueAsUnsigned() != 0
        return isCFColor


def _showColor(color):
    color = "(" + color + ")"

    colorToUse = color
    isCF = _colorIsCGColorRef(color)
    if isCF:
        colorToUse = "[[UIColor alloc] initWithCGColor:(CGColorRef){}]".format(color)
    else:
        isCI = objectHelpers.isKindOfClass(color, "CIColor")
        if isCI:
            colorToUse = "[UIColor colorWithCIColor:(CIColor *){}]".format(color)

    imageSize = 58
    fb.evaluateEffect(
        "UIGraphicsBeginImageContextWithOptions((CGSize)CGSizeMake({imageSize}, {imageSize}), NO, 0.0)".format(
            imageSize=imageSize
        )
    )
    fb.evaluateEffect("[(id){} setFill]".format(colorToUse))
    fb.evaluateEffect(
        "UIRectFill((CGRect)CGRectMake(0.0, 0.0, {imageSize}, {imageSize}))".format(
            imageSize=imageSize
        )
    )

    result = fb.evaluateExpressionValue(
        "(UIImage *)UIGraphicsGetImageFromCurrentImageContext()"
    )
    if result.GetError() is not None and str(result.GetError()) != "success":
        print("got error {}".format(result))
        print(result.GetError())
    else:
        image = result.GetValue()
        _showImage(image)

    fb.evaluateEffect("UIGraphicsEndImageContext()")


def _showLayer(layer):
    layer = "(" + layer + ")"
    size = "((CGRect)[(id)" + layer + " bounds]).size"

    width = float(fb.evaluateExpression("(CGFloat)(" + size + ".width)"))
    height = float(fb.evaluateExpression("(CGFloat)(" + size + ".height)"))
    if width == 0.0 or height == 0.0:
        print(
            "Nothing to see here - the size of this element is {} x {}.".format(
                width, height
            )
        )
        return

    fb.evaluateEffect("UIGraphicsBeginImageContextWithOptions(" + size + ", NO, 0.0)")
    fb.evaluateEffect(
        "[(id)" + layer + " renderInContext:(void *)UIGraphicsGetCurrentContext()]"
    )

    result = fb.evaluateExpressionValue(
        "(UIImage *)UIGraphicsGetImageFromCurrentImageContext()"
    )
    if result.GetError() is not None and str(result.GetError()) != "success":
        print(result.GetError())
    else:
        image = result.GetValue()
        _showImage(image)

    fb.evaluateEffect("UIGraphicsEndImageContext()")


def _showPixelBuffer(target):
    fb.evaluateExpression("CGImageRef $imageOut = NULL")
    fb.evaluateExpression(
        "(OSStatus)VTCreateCGImageFromCVPixelBuffer(" + target + ", NULL, &$imageOut)"
    )
    image = fb.evaluateExpression("[UIImage imageWithCGImage:$imageOut]")
    _showImage(image)
    fb.evaluateExpression("CGImageRelease($imageOut)")


def _dataIsImage(data):
    data = "(" + data + ")"

    result = fb.evaluateExpressionValue("(id)[UIImage imageWithData:" + data + "]")

    if result.GetError() is not None and str(result.GetError()) != "success":
        return False
    else:
        isImage = result.GetValueAsUnsigned() != 0
        return isImage


def _dataIsString(data):
    data = "(" + data + ")"

    result = fb.evaluateExpressionValue(
        "(NSString*)[[NSString alloc] initWithData:" + data + " encoding:4]"
    )

    if result.GetError() is not None and str(result.GetError()) != "success":
        return False
    else:
        isString = result.GetValueAsUnsigned() != 0
        return isString


def _visualize(target):
    target = fb.evaluateInputExpression(target)

    if fb.evaluateBooleanExpression(
        "(unsigned long)CFGetTypeID((CFTypeRef)"
        + target
        + ") == (unsigned long)CGImageGetTypeID()"
    ):
        _showImage("(id)[UIImage imageWithCGImage:" + target + "]")
    elif fb.evaluateBooleanExpression(
        "(unsigned long)CFGetTypeID((CFTypeRef)"
        + target
        + ") == (unsigned long)CVPixelBufferGetTypeID()"
    ):
        _showPixelBuffer(target)
    else:
        if objectHelpers.isKindOfClass(target, "UIImage"):
            _showImage(target)
        elif objectHelpers.isKindOfClass(target, "UIView"):
            _showLayer("[(id)" + target + " layer]")
        elif objectHelpers.isKindOfClass(target, "CALayer"):
            _showLayer(target)
        elif (
            objectHelpers.isKindOfClass(target, "UIColor")
            or objectHelpers.isKindOfClass(target, "CIColor")
            or _colorIsCGColorRef(target)
        ):
            _showColor(target)
        elif objectHelpers.isKindOfClass(target, "NSData"):
            if _dataIsImage(target):
                _showImage("(id)[UIImage imageWithData:" + target + "]")
            elif _dataIsString(target):
                print(
                    fb.describeObject(
                        "[[NSString alloc] initWithData:" + target + " encoding:4]"
                    )
                )
            else:
                print("Data isn't an image and isn't a string.")
        else:
            print(
                "{} isn't supported. You can visualize UIImage, CGImageRef, UIView, CALayer, NSData, UIColor, CIColor, or CGColorRef.".format(
                    objectHelpers.className(target)
                )
            )


class FBVisualizeCommand(fb.FBCommand):
    def name(self):
        return "visualize"

    def description(self):
        return "Open a UIImage, CGImageRef, UIView, CALayer, or CVPixelBuffer in Preview.app on your Mac."

    def args(self):
        return [
            fb.FBCommandArgument(
                arg="target", type="(id)", help="The object to visualize."
            )
        ]

    def run(self, arguments, options):
        _visualize(arguments[0])