github.com/luchsh/agentlib.go@v0.0.0-20221115155834-ffd0caec4d72/jgo/load.go (about)

     1  //
     2  // Copyright 2020 chuanshenglu@gmail.com
     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 jgo
    18  
    19  //#include "wrapper.h"
    20  import "C"
    21  
    22  // AgentLib defines the information of a agent library
    23  type AgentLib struct {
    24  	// The unique instance of JavaVM
    25  	javaVM JVM
    26  	// command line options to this agent
    27  	Options string
    28  	// current jvmti env
    29  	jvmti jvmtiEnv
    30  	// Callbacks
    31  	callbacks JvmtiCallbacks
    32  }
    33  
    34  // GetCallbacks returns the callbacks of this lib
    35  func (agent *AgentLib) GetCallbacks() *JvmtiCallbacks {
    36  	return &agent.callbacks
    37  }
    38  
    39  // The global instance of this agent lib
    40  var (
    41  	_lib *AgentLib
    42  	Onload AgentOnLoadCallback
    43  	Onunload AgentOnUnloadCallback
    44  )
    45  
    46  type AgentOnLoadCallback func(*AgentLib)
    47  type AgentOnUnloadCallback func()
    48  
    49  //export OnAgentLoad
    50  func OnAgentLoad(javaVM, jvmti uintptr, options *C.char) {
    51  	_lib = new(AgentLib)
    52  	_lib.javaVM = JVM(javaVM)
    53  	_lib.Options = C.GoString(options)
    54  	_lib.jvmti = jvmtiEnv(jvmti)
    55  	_lib.callbacks.init()
    56  
    57  	if Onload != nil {
    58  		Onload(_lib)
    59  	}
    60  }
    61  
    62  //export OnAgentUnload
    63  func OnAgentUnload() int32 {
    64  	if Onunload != nil {
    65  		Onunload()
    66  	}
    67  	return 0
    68  }
    69  
    70  //export MainForwardLoop
    71  func MainForwardLoop() {
    72         // TODO: cross-runtime forwarding mechanism
    73  }