--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/services/diagnosticFramework.hpp Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,490 @@
+/*
+ * Copyright (c) 2011, 2014, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+#ifndef SHARE_VM_SERVICES_DIAGNOSTICFRAMEWORK_HPP
+#define SHARE_VM_SERVICES_DIAGNOSTICFRAMEWORK_HPP
+
+#include "classfile/vmSymbols.hpp"
+#include "memory/allocation.hpp"
+#include "runtime/arguments.hpp"
+#include "runtime/os.hpp"
+#include "runtime/vmThread.hpp"
+#include "utilities/ostream.hpp"
+
+
+enum DCmdSource {
+ DCmd_Source_Internal = 0x01U, // invocation from the JVM
+ DCmd_Source_AttachAPI = 0x02U, // invocation via the attachAPI
+ DCmd_Source_MBean = 0x04U // invocation via a MBean
+};
+
+// Warning: strings referenced by the JavaPermission struct are passed to
+// the native part of the JDK. Avoid use of dynamically allocated strings
+// that could be de-allocated before the JDK native code had time to
+// convert them into Java Strings.
+struct JavaPermission {
+ const char* _class;
+ const char* _name;
+ const char* _action;
+};
+
+// CmdLine is the class used to handle a command line containing a single
+// diagnostic command and its arguments. It provides methods to access the
+// command name and the beginning of the arguments. The class is also
+// able to identify commented command lines and the "stop" keyword
+class CmdLine : public StackObj {
+private:
+ const char* _cmd;
+ size_t _cmd_len;
+ const char* _args;
+ size_t _args_len;
+public:
+ CmdLine(const char* line, size_t len, bool no_command_name);
+ const char* args_addr() const { return _args; }
+ size_t args_len() const { return _args_len; }
+ const char* cmd_addr() const { return _cmd; }
+ size_t cmd_len() const { return _cmd_len; }
+ bool is_empty() { return _cmd_len == 0; }
+ bool is_executable() { return is_empty() || _cmd[0] != '#'; }
+ bool is_stop() { return !is_empty() && strncmp("stop", _cmd, _cmd_len) == 0; }
+};
+
+// Iterator class taking a character string in input and returning a CmdLine
+// instance for each command line. The argument delimiter has to be specified.
+class DCmdIter : public StackObj {
+ friend class DCmd;
+private:
+ const char* _str;
+ char _delim;
+ size_t _len;
+ size_t _cursor;
+public:
+
+ DCmdIter(const char* str, char delim) {
+ _str = str;
+ _delim = delim;
+ _len = strlen(str);
+ _cursor = 0;
+ }
+ bool has_next() { return _cursor < _len; }
+ CmdLine next() {
+ assert(_cursor <= _len, "Cannot iterate more");
+ size_t n = _cursor;
+ while (n < _len && _str[n] != _delim) n++;
+ CmdLine line(&(_str[_cursor]), n - _cursor, false);
+ _cursor = n + 1;
+ // The default copy constructor of CmdLine is used to return a CmdLine
+ // instance to the caller.
+ return line;
+ }
+};
+
+// Iterator class to iterate over diagnostic command arguments
+class DCmdArgIter : public ResourceObj {
+ const char* _buffer;
+ size_t _len;
+ size_t _cursor;
+ const char* _key_addr;
+ size_t _key_len;
+ const char* _value_addr;
+ size_t _value_len;
+ char _delim;
+public:
+ DCmdArgIter(const char* buf, size_t len, char delim) {
+ _buffer = buf;
+ _len = len;
+ _delim = delim;
+ _cursor = 0;
+ }
+ bool next(TRAPS);
+ const char* key_addr() { return _key_addr; }
+ size_t key_length() { return _key_len; }
+ const char* value_addr() { return _value_addr; }
+ size_t value_length() { return _value_len; }
+};
+
+// A DCmdInfo instance provides a description of a diagnostic command. It is
+// used to export the description to the JMX interface of the framework.
+class DCmdInfo : public ResourceObj {
+protected:
+ const char* _name; /* Name of the diagnostic command */
+ const char* _description; /* Short description */
+ const char* _impact; /* Impact on the JVM */
+ JavaPermission _permission; /* Java Permission required to execute this command if any */
+ int _num_arguments; /* Number of supported options or arguments */
+ bool _is_enabled; /* True if the diagnostic command can be invoked, false otherwise */
+public:
+ DCmdInfo(const char* name,
+ const char* description,
+ const char* impact,
+ JavaPermission permission,
+ int num_arguments,
+ bool enabled) {
+ this->_name = name;
+ this->_description = description;
+ this->_impact = impact;
+ this->_permission = permission;
+ this->_num_arguments = num_arguments;
+ this->_is_enabled = enabled;
+ }
+ const char* name() const { return _name; }
+ const char* description() const { return _description; }
+ const char* impact() const { return _impact; }
+ JavaPermission permission() const { return _permission; }
+ int num_arguments() const { return _num_arguments; }
+ bool is_enabled() const { return _is_enabled; }
+
+ static bool by_name(void* name, DCmdInfo* info);
+};
+
+// A DCmdArgumentInfo instance provides a description of a diagnostic command
+// argument. It is used to export the description to the JMX interface of the
+// framework.
+class DCmdArgumentInfo : public ResourceObj {
+protected:
+ const char* _name; /* Option/Argument name*/
+ const char* _description; /* Short description */
+ const char* _type; /* Type: STRING, BOOLEAN, etc. */
+ const char* _default_string; /* Default value in a parsable string */
+ bool _mandatory; /* True if the option/argument is mandatory */
+ bool _option; /* True if it is an option, false if it is an argument */
+ /* (see diagnosticFramework.hpp for option/argument definitions) */
+ bool _multiple; /* True is the option can be specified several time */
+ int _position; /* Expected position for this argument (this field is */
+ /* meaningless for options) */
+public:
+ DCmdArgumentInfo(const char* name, const char* description, const char* type,
+ const char* default_string, bool mandatory, bool option,
+ bool multiple) {
+ this->_name = name;
+ this->_description = description;
+ this->_type = type;
+ this->_default_string = default_string;
+ this->_option = option;
+ this->_mandatory = mandatory;
+ this->_option = option;
+ this->_multiple = multiple;
+ this->_position = -1;
+ }
+ DCmdArgumentInfo(const char* name, const char* description, const char* type,
+ const char* default_string, bool mandatory, bool option,
+ bool multiple, int position) {
+ this->_name = name;
+ this->_description = description;
+ this->_type = type;
+ this->_default_string = default_string;
+ this->_option = option;
+ this->_mandatory = mandatory;
+ this->_option = option;
+ this->_multiple = multiple;
+ this->_position = position;
+ }
+ const char* name() const { return _name; }
+ const char* description() const { return _description; }
+ const char* type() const { return _type; }
+ const char* default_string() const { return _default_string; }
+ bool is_mandatory() const { return _mandatory; }
+ bool is_option() const { return _option; }
+ bool is_multiple() const { return _multiple; }
+ int position() const { return _position; }
+};
+
+// The DCmdParser class can be used to create an argument parser for a
+// diagnostic command. It is not mandatory to use it to parse arguments.
+// The DCmdParser parses a CmdLine instance according to the parameters that
+// have been declared by its associated diagnostic command. A parameter can
+// either be an option or an argument. Options are identified by the option name
+// while arguments are identified by their position in the command line. The
+// position of an argument is defined relative to all arguments passed on the
+// command line, options are not considered when defining an argument position.
+// The generic syntax of a diagnostic command is:
+//
+// <command name> [<option>=<value>] [<argument_value>]
+//
+// Example:
+//
+// command_name option1=value1 option2=value argumentA argumentB argumentC
+//
+// In this command line, the diagnostic command receives five parameters, two
+// options named option1 and option2, and three arguments. argumentA's position
+// is 0, argumentB's position is 1 and argumentC's position is 2.
+class DCmdParser {
+private:
+ GenDCmdArgument* _options;
+ GenDCmdArgument* _arguments_list;
+ char _delim;
+public:
+ DCmdParser() {
+ _options = NULL;
+ _arguments_list = NULL;
+ _delim = ' ';
+ }
+ void add_dcmd_option(GenDCmdArgument* arg);
+ void add_dcmd_argument(GenDCmdArgument* arg);
+ GenDCmdArgument* lookup_dcmd_option(const char* name, size_t len);
+ GenDCmdArgument* arguments_list() { return _arguments_list; };
+ void check(TRAPS);
+ void parse(CmdLine* line, char delim, TRAPS);
+ void print_help(outputStream* out, const char* cmd_name);
+ void reset(TRAPS);
+ void cleanup();
+ int num_arguments();
+ GrowableArray<const char*>* argument_name_array();
+ GrowableArray<DCmdArgumentInfo*>* argument_info_array();
+};
+
+// The DCmd class is the parent class of all diagnostic commands
+// Diagnostic command instances should not be instantiated directly but
+// created using the associated factory. The factory can be retrieved with
+// the DCmdFactory::getFactory() method.
+// A diagnostic command instance can either be allocated in the resource Area
+// or in the C-heap. Allocation in the resource area is recommended when the
+// current thread is the only one which will access the diagnostic command
+// instance. Allocation in the C-heap is required when the diagnostic command
+// is accessed by several threads (for instance to perform asynchronous
+// execution).
+// To ensure a proper cleanup, it's highly recommended to use a DCmdMark for
+// each diagnostic command instance. In case of a C-heap allocated diagnostic
+// command instance, the DCmdMark must be created in the context of the last
+// thread that will access the instance.
+class DCmd : public ResourceObj {
+protected:
+ outputStream* _output;
+ bool _is_heap_allocated;
+public:
+ DCmd(outputStream* output, bool heap_allocated) {
+ _output = output;
+ _is_heap_allocated = heap_allocated;
+ }
+
+ static const char* name() { return "No Name";}
+ static const char* description() { return "No Help";}
+ static const char* disabled_message() { return "Diagnostic command currently disabled"; }
+ // The impact() method returns a description of the intrusiveness of the diagnostic
+ // command on the Java Virtual Machine behavior. The rational for this method is that some
+ // diagnostic commands can seriously disrupt the behavior of the Java Virtual Machine
+ // (for instance a Thread Dump for an application with several tens of thousands of threads,
+ // or a Head Dump with a 40GB+ heap size) and other diagnostic commands have no serious
+ // impact on the JVM (for instance, getting the command line arguments or the JVM version).
+ // The recommended format for the description is <impact level>: [longer description],
+ // where the impact level is selected among this list: {Low, Medium, High}. The optional
+ // longer description can provide more specific details like the fact that Thread Dump
+ // impact depends on the heap size.
+ static const char* impact() { return "Low: No impact"; }
+ // The permission() method returns the description of Java Permission. This
+ // permission is required when the diagnostic command is invoked via the
+ // DiagnosticCommandMBean. The rationale for this permission check is that
+ // the DiagnosticCommandMBean can be used to perform remote invocations of
+ // diagnostic commands through the PlatformMBeanServer. The (optional) Java
+ // Permission associated with each diagnostic command should ease the work
+ // of system administrators to write policy files granting permissions to
+ // execute diagnostic commands to remote users. Any diagnostic command with
+ // a potential impact on security should overwrite this method.
+ static const JavaPermission permission() {
+ JavaPermission p = {NULL, NULL, NULL};
+ return p;
+ }
+ static int num_arguments() { return 0; }
+ outputStream* output() { return _output; }
+ bool is_heap_allocated() { return _is_heap_allocated; }
+ virtual void print_help(const char* name) {
+ output()->print_cr("Syntax: %s", name);
+ }
+ virtual void parse(CmdLine* line, char delim, TRAPS) {
+ DCmdArgIter iter(line->args_addr(), line->args_len(), delim);
+ bool has_arg = iter.next(CHECK);
+ if (has_arg) {
+ THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(),
+ "The argument list of this diagnostic command should be empty.");
+ }
+ }
+ virtual void execute(DCmdSource source, TRAPS) { }
+ virtual void reset(TRAPS) { }
+ virtual void cleanup() { }
+
+ // support for the JMX interface
+ virtual GrowableArray<const char*>* argument_name_array() {
+ GrowableArray<const char*>* array = new GrowableArray<const char*>(0);
+ return array;
+ }
+ virtual GrowableArray<DCmdArgumentInfo*>* argument_info_array() {
+ GrowableArray<DCmdArgumentInfo*>* array = new GrowableArray<DCmdArgumentInfo*>(0);
+ return array;
+ }
+
+ // main method to invoke the framework
+ static void parse_and_execute(DCmdSource source, outputStream* out, const char* cmdline,
+ char delim, TRAPS);
+};
+
+class DCmdWithParser : public DCmd {
+protected:
+ DCmdParser _dcmdparser;
+public:
+ DCmdWithParser (outputStream *output, bool heap=false) : DCmd(output, heap) { }
+ static const char* name() { return "No Name";}
+ static const char* description() { return "No Help";}
+ static const char* disabled_message() { return "Diagnostic command currently disabled"; }
+ static const char* impact() { return "Low: No impact"; }
+ static const JavaPermission permission() {JavaPermission p = {NULL, NULL, NULL}; return p; }
+ static int num_arguments() { return 0; }
+ virtual void parse(CmdLine *line, char delim, TRAPS);
+ virtual void execute(DCmdSource source, TRAPS) { }
+ virtual void reset(TRAPS);
+ virtual void cleanup();
+ virtual void print_help(const char* name);
+ virtual GrowableArray<const char*>* argument_name_array();
+ virtual GrowableArray<DCmdArgumentInfo*>* argument_info_array();
+};
+
+class DCmdMark : public StackObj {
+ DCmd* _ref;
+public:
+ DCmdMark(DCmd* cmd) { _ref = cmd; }
+ ~DCmdMark() {
+ if (_ref != NULL) {
+ _ref->cleanup();
+ if (_ref->is_heap_allocated()) {
+ delete _ref;
+ }
+ }
+ }
+};
+
+// Diagnostic commands are not directly instantiated but created with a factory.
+// Each diagnostic command class has its own factory. The DCmdFactory class also
+// manages the status of the diagnostic command (hidden, enabled). A DCmdFactory
+// has to be registered to make the diagnostic command available (see
+// management.cpp)
+class DCmdFactory: public CHeapObj<mtInternal> {
+private:
+ static Mutex* _dcmdFactory_lock;
+ static bool _send_jmx_notification;
+ static bool _has_pending_jmx_notification;
+ // Pointer to the next factory in the singly-linked list of registered
+ // diagnostic commands
+ DCmdFactory* _next;
+ // When disabled, a diagnostic command cannot be executed. Any attempt to
+ // execute it will result in the printing of the disabled message without
+ // instantiating the command.
+ bool _enabled;
+ // When hidden, a diagnostic command doesn't appear in the list of commands
+ // provided by the 'help' command.
+ bool _hidden;
+ uint32_t _export_flags;
+ int _num_arguments;
+ static DCmdFactory* _DCmdFactoryList;
+public:
+ DCmdFactory(int num_arguments, uint32_t flags, bool enabled, bool hidden) {
+ _next = NULL;
+ _enabled = enabled;
+ _hidden = hidden;
+ _export_flags = flags;
+ _num_arguments = num_arguments;
+ }
+ bool is_enabled() const { return _enabled; }
+ void set_enabled(bool b) { _enabled = b; }
+ bool is_hidden() const { return _hidden; }
+ void set_hidden(bool b) { _hidden = b; }
+ uint32_t export_flags() { return _export_flags; }
+ void set_export_flags(uint32_t f) { _export_flags = f; }
+ int num_arguments() { return _num_arguments; }
+ DCmdFactory* next() { return _next; }
+ virtual DCmd* create_Cheap_instance(outputStream* output) = 0;
+ virtual DCmd* create_resource_instance(outputStream* output) = 0;
+ virtual const char* name() const = 0;
+ virtual const char* description() const = 0;
+ virtual const char* impact() const = 0;
+ virtual const JavaPermission permission() const = 0;
+ virtual const char* disabled_message() const = 0;
+ // Register a DCmdFactory to make a diagnostic command available.
+ // Once registered, a diagnostic command must not be unregistered.
+ // To prevent a diagnostic command from being executed, just set the
+ // enabled flag to false.
+ static int register_DCmdFactory(DCmdFactory* factory);
+ static DCmdFactory* factory(DCmdSource source, const char* cmd, size_t len);
+ // Returns a C-heap allocated diagnostic command for the given command line
+ static DCmd* create_global_DCmd(DCmdSource source, CmdLine &line, outputStream* out, TRAPS);
+ // Returns a resourceArea allocated diagnostic command for the given command line
+ static DCmd* create_local_DCmd(DCmdSource source, CmdLine &line, outputStream* out, TRAPS);
+ static GrowableArray<const char*>* DCmd_list(DCmdSource source);
+ static GrowableArray<DCmdInfo*>* DCmdInfo_list(DCmdSource source);
+
+ static void set_jmx_notification_enabled(bool enabled) {
+ _send_jmx_notification = enabled;
+ }
+ static void push_jmx_notification_request();
+ static bool has_pending_jmx_notification() { return _has_pending_jmx_notification; }
+ static void send_notification(TRAPS);
+private:
+ static void send_notification_internal(TRAPS);
+
+ friend class HelpDCmd;
+};
+
+// Template to easily create DCmdFactory instances. See management.cpp
+// where this template is used to create and register factories.
+template <class DCmdClass> class DCmdFactoryImpl : public DCmdFactory {
+public:
+ DCmdFactoryImpl(uint32_t flags, bool enabled, bool hidden) :
+ DCmdFactory(DCmdClass::num_arguments(), flags, enabled, hidden) { }
+ // Returns a C-heap allocated instance
+ virtual DCmd* create_Cheap_instance(outputStream* output) {
+ return new (ResourceObj::C_HEAP, mtInternal) DCmdClass(output, true);
+ }
+ // Returns a resourceArea allocated instance
+ virtual DCmd* create_resource_instance(outputStream* output) {
+ return new DCmdClass(output, false);
+ }
+ virtual const char* name() const {
+ return DCmdClass::name();
+ }
+ virtual const char* description() const {
+ return DCmdClass::description();
+ }
+ virtual const char* impact() const {
+ return DCmdClass::impact();
+ }
+ virtual const JavaPermission permission() const {
+ return DCmdClass::permission();
+ }
+ virtual const char* disabled_message() const {
+ return DCmdClass::disabled_message();
+ }
+};
+
+// This class provides a convenient way to register Dcmds, without a need to change
+// management.cpp every time. Body of these two methods resides in
+// diagnosticCommand.cpp
+
+class DCmdRegistrant : public AllStatic {
+
+private:
+ static void register_dcmds();
+ static void register_dcmds_ext();
+
+ friend class Management;
+};
+
+#endif // SHARE_VM_SERVICES_DIAGNOSTICFRAMEWORK_HPP