Sogou input method double-click input box crash problem | JD Cloud technical team

Foreword:

Whenever there are big promotions like 618 and Double 11, search, as the core function of the entire app, not only serves as the traffic entrance, but also carries the service and experience that users perceive this product in the shopping guide scene, so guarantee search to better help 618 sell well.

Phenomenon:

Double-click the Sogou input box to invoke the keyboard crash

monitoring platform:

The monitoring platform detects a large number of crashes, and the phenomenon is that the keyboard responds in a very short time interval.

Mental journey:

By observing the phenomenon, it is guessed that the user copied the keyword through WeChat or other software , and then came to JD Wanshang to paste the search function. It may be due to some reasons (the copy permission prompt pop-up window did not pop up) that the paste function did not appear in the search box, and the user frantically double-clicked the input box at this time. So I started to test the apps on the market. Taking JD App as an example, the steps to reproduce are as follows:

The test results are as follows:

App	Does it crash	frequency
Jingdong	yes	high
JD.com	yes	high
seven fresh	yes	high
Taobao	no
Alipay	yes	middle
baidu	yes	middle
Baidu map	no
meituan	no
Hema	no
1688	no
Bilibili	no
Tik Tok	yes	Low

The crash logs obtained through mobile phone privacy are Jingme, Jingdong, Baidu , and the performance is the same as that of the SGM platform.

Source code debugging:

Debugging results through Xcode breakpoints are as follows:

UICompatibilityInputViewController excessive release

crash in_wantsForwardingFromResponder:toNextResponder:withEvent

solution:

Give the crash method a default implementation through the runtime pair

static BOOL (*originalImpl)(id, SEL, UIResponder*, UIResponder*, UIEvent* ) = nil;


- (BOOL)_wantsForwardingFromResponder:(UIResponder *)arg1 toNextResponder:(UIResponder *)arg2 withEvent:(UIEvent *)arg3 {
    NSString* responderClassName = NSStringFromClass([arg2 class]);
    if ([responderClassName isEqualToString:@"_UIRemoteInputViewController"]) {
        bool isDeallocating = false;
        // isDeallocating = _objc_rootIsDeallocating(arg2);

        // Use 'performSelector' when u are develop a App-Store App.
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Warc-performSelector-leaks"
        SEL sel = NSSelectorFromString(@"_isDeallocating");
        isDeallocating = [arg2 respondsToSelector:sel] && [arg2 performSelector:sel];
#pragma clang diagnostic pop

        if (isDeallocating) {
            NSLog(@"BingGo a deallocating object ...");
            return true;
        }
    }

    BOOL retVal = FALSE;
    if (originalImpl == nil) {
        IMP impl = [ObjcSeeker seekInstanceNextOirignalImpl:self selector:_cmd];
        originalImpl = (BOOL (*)(id, SEL, UIResponder*, UIResponder*, UIEvent* ))impl;
    }

    if (originalImpl != nil) {
        retVal = originalImpl(self, _cmd, arg1, arg2, arg3);
    }
    return retVal;
}

Reference link:

https://github.com/SnowGirls/Objc-Deallocating

Author: JD Retail Tu Shizhan

Source: JD Cloud Developer Community