github.com/google/syzkaller@v0.0.0-20240517125934-c0f1611a36d6/pkg/fuzzer/queue/retry.go (about)

     1  // Copyright 2024 syzkaller project authors. All rights reserved.
     2  // Use of this source code is governed by Apache 2 LICENSE that can be found in the LICENSE file.
     3  
     4  package queue
     5  
     6  type retryer struct {
     7  	pq   *PlainQueue
     8  	base Source
     9  }
    10  
    11  // Retry adds a layer that resends results with Status=Restarted.
    12  func Retry(base Source) Source {
    13  	return &retryer{
    14  		base: base,
    15  		pq:   Plain(),
    16  	}
    17  }
    18  
    19  func (r *retryer) Next() *Request {
    20  	req := r.pq.tryNext()
    21  	if req == nil {
    22  		req = r.base.Next()
    23  	}
    24  	if req != nil {
    25  		req.OnDone(r.done)
    26  	}
    27  	return req
    28  }
    29  
    30  func (r *retryer) done(req *Request, res *Result) bool {
    31  	// The input was on a restarted VM.
    32  	if res.Status == Restarted {
    33  		r.pq.Submit(req)
    34  		return false
    35  	}
    36  	// Retry important requests from crashed VMs once.
    37  	if res.Status == Crashed && req.Important && !req.onceCrashed {
    38  		req.onceCrashed = true
    39  		r.pq.Submit(req)
    40  		return false
    41  	}
    42  	return true
    43  }