| /* |
| * 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 |