Sun, 03 Feb 2013 22:28:08 +0400
8002048: Protocol to discovery of manageable Java processes on a network
Summary: Introduce a protocol to discover manageble Java instances across a network subnet, JDP
Reviewed-by: sla, dfuchs
1 /*
2 * Copyright (c) 2005, 2013, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
25 #ifndef SHARE_VM_SERVICES_ATTACHLISTENER_HPP
26 #define SHARE_VM_SERVICES_ATTACHLISTENER_HPP
28 #include "memory/allocation.hpp"
29 #include "utilities/debug.hpp"
30 #include "utilities/ostream.hpp"
32 // The AttachListener thread services a queue of operations that are enqueued
33 // by client tools. Each operation is identified by a name and has up to 3
34 // arguments. The operation name is mapped to a function which performs the
35 // operation. The function is called with an outputStream which is can use to
36 // write any result data (for examples the properties command serializes
37 // properties names and values to the output stream). When the function
38 // complets the result value and any result data is returned to the client
39 // tool.
41 class AttachOperation;
43 typedef jint (*AttachOperationFunction)(AttachOperation* op, outputStream* out);
45 struct AttachOperationFunctionInfo {
46 const char* name;
47 AttachOperationFunction func;
48 };
50 class AttachListener: AllStatic {
51 public:
52 static void init() NOT_SERVICES_RETURN;
53 static void abort() NOT_SERVICES_RETURN;
55 // invoke to perform clean-up tasks when all clients detach
56 static void detachall() NOT_SERVICES_RETURN;
58 // indicates if the Attach Listener needs to be created at startup
59 static bool init_at_startup() NOT_SERVICES_RETURN_(false);
61 // indicates if we have a trigger to start the Attach Listener
62 static bool is_init_trigger() NOT_SERVICES_RETURN_(false);
64 #if !INCLUDE_SERVICES
65 static bool is_attach_supported() { return false; }
66 #else
67 private:
68 static volatile bool _initialized;
70 public:
71 static bool is_initialized() { return _initialized; }
72 static void set_initialized() { _initialized = true; }
74 // indicates if this VM supports attach-on-demand
75 static bool is_attach_supported() { return !DisableAttachMechanism; }
77 // platform specific initialization
78 static int pd_init();
80 // platform specific operation
81 static AttachOperationFunctionInfo* pd_find_operation(const char* name);
83 // platform specific flag change
84 static jint pd_set_flag(AttachOperation* op, outputStream* out);
86 // platform specific detachall
87 static void pd_detachall();
89 // platform specific data dump
90 static void pd_data_dump();
92 // dequeue the next operation
93 static AttachOperation* dequeue();
94 #endif // !INCLUDE_SERVICES
95 };
97 #if INCLUDE_SERVICES
98 class AttachOperation: public CHeapObj<mtInternal> {
99 public:
100 enum {
101 name_length_max = 16, // maximum length of name
102 arg_length_max = 1024, // maximum length of argument
103 arg_count_max = 3 // maximum number of arguments
104 };
106 // name of special operation that can be enqueued when all
107 // clients detach
108 static char* detachall_operation_name() { return (char*)"detachall"; }
110 private:
111 char _name[name_length_max+1];
112 char _arg[arg_count_max][arg_length_max+1];
114 public:
115 const char* name() const { return _name; }
117 // set the operation name
118 void set_name(char* name) {
119 assert(strlen(name) <= name_length_max, "exceeds maximum name length");
120 strcpy(_name, name);
121 }
123 // get an argument value
124 const char* arg(int i) const {
125 assert(i>=0 && i<arg_count_max, "invalid argument index");
126 return _arg[i];
127 }
129 // set an argument value
130 void set_arg(int i, char* arg) {
131 assert(i>=0 && i<arg_count_max, "invalid argument index");
132 if (arg == NULL) {
133 _arg[i][0] = '\0';
134 } else {
135 assert(strlen(arg) <= arg_length_max, "exceeds maximum argument length");
136 strcpy(_arg[i], arg);
137 }
138 }
140 // create an operation of a given name
141 AttachOperation(char* name) {
142 set_name(name);
143 for (int i=0; i<arg_count_max; i++) {
144 set_arg(i, NULL);
145 }
146 }
148 // complete operation by sending result code and any result data to the client
149 virtual void complete(jint result, bufferedStream* result_stream) = 0;
150 };
151 #endif // INCLUDE_SERVICES
153 #endif // SHARE_VM_SERVICES_ATTACHLISTENER_HPP