github.com/bytedance/mockey@v1.2.10/internal/monkey/mem/write.go (about)

     1  /*
     2   * Copyright 2022 ByteDance Inc.
     3   *
     4   * Licensed under the Apache License, Version 2.0 (the "License");
     5   * you may not use this file except in compliance with the License.
     6   * You may obtain a copy of the License at
     7   *
     8   *     http://www.apache.org/licenses/LICENSE-2.0
     9   *
    10   * Unless required by applicable law or agreed to in writing, software
    11   * distributed under the License is distributed on an "AS IS" BASIS,
    12   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13   * See the License for the specific language governing permissions and
    14   * limitations under the License.
    15   */
    16  
    17  package mem
    18  
    19  import (
    20  	"github.com/bytedance/mockey/internal/monkey/common"
    21  	"github.com/bytedance/mockey/internal/tool"
    22  )
    23  
    24  // WriteWithSTW copies data bytes to the target address and replaces the original bytes, during which it will stop the
    25  // world (only the current goroutine's P is running).
    26  func WriteWithSTW(target uintptr, data []byte) {
    27  	common.StopTheWorld()
    28  
    29  	begin := target
    30  	end := target + uintptr(len(data))
    31  	for begin < end {
    32  		if common.PageOf(begin) < common.PageOf(end) {
    33  			nextPage := common.PageOf(begin) + uintptr(common.PageSize())
    34  			buf := data[:nextPage-begin]
    35  			data = data[nextPage-begin:]
    36  			err := Write(begin, buf)
    37  			tool.Assert(err == nil, err)
    38  			begin += uintptr(len(buf))
    39  			continue
    40  		}
    41  		err := Write(begin, data)
    42  		tool.Assert(err == nil, err)
    43  		break
    44  	}
    45  
    46  	common.StartTheWorld()
    47  }