src/jdk.management/share/native/libmanagement_ext/DiagnosticCommandImpl.c

/*
 * Copyright (c) 2013, 2024, 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.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * 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.
 */

#include <stdlib.h>
#include <jni.h>
#include "management_ext.h"
#include "com_sun_management_internal_DiagnosticCommandImpl.h"

JNIEXPORT void JNICALL Java_com_sun_management_internal_DiagnosticCommandImpl_setNotificationEnabled
(JNIEnv *env, jobject dummy, jboolean enabled) {
    if (jmm_version_management_ext <= JMM_VERSION_1_2_2) {
        JNU_ThrowByName(env, "java/lang/UnsupportedOperationException",
                        "JMX interface to diagnostic framework notifications is not supported by this VM");
        return;
    }
    jmm_interface_management_ext->SetDiagnosticFrameworkNotificationEnabled(env, enabled);
}

JNIEXPORT jobjectArray JNICALL
Java_com_sun_management_internal_DiagnosticCommandImpl_getDiagnosticCommands
  (JNIEnv *env, jobject dummy)
{
  return jmm_interface_management_ext->GetDiagnosticCommands(env);
}

//
// Checks for an exception and if one occurred,
// pops 'pops' local frames and frees 'x' before
// returning NULL
//
#define POP_EXCEPTION_CHECK_AND_FREE(pops, x) do { \
                                                  if ((*env)->ExceptionCheck(env)) { \
                                                      int i; \
                                                      for (i = 0; i < pops; i++) { \
                                                          (*env)->PopLocalFrame(env, NULL); \
                                                      } \
                                                      free(x); \
                                                      return NULL; \
                                                  } \
                                              } while(0)

jobject getDiagnosticCommandArgumentInfoArray(JNIEnv *env, jstring command,
                                              int num_arg) {
  int i;
  jobject obj;
  jobjectArray result;
  dcmdArgInfo* dcmd_arg_info_array;
  jclass dcmdArgInfoCls;
  jclass arraysCls;
  jmethodID mid;
  jobject resultList;

  dcmd_arg_info_array = (dcmdArgInfo*) malloc(num_arg * sizeof(dcmdArgInfo));
  /* According to ISO C it is perfectly legal for malloc to return zero if called with a zero argument */
  if (dcmd_arg_info_array == NULL && num_arg != 0) {
    JNU_ThrowOutOfMemoryError(env, 0);
    return NULL;
  }
  jmm_interface_management_ext->GetDiagnosticCommandArgumentsInfo(env, command,
                                                   dcmd_arg_info_array, num_arg);
  dcmdArgInfoCls = (*env)->FindClass(env,
                                     "com/sun/management/internal/DiagnosticCommandArgumentInfo");
  POP_EXCEPTION_CHECK_AND_FREE(0, dcmd_arg_info_array);

  result = (*env)->NewObjectArray(env, num_arg, dcmdArgInfoCls, NULL);
  if (result == NULL) {
    free(dcmd_arg_info_array);
    return NULL;
  }
  for (i=0; i<num_arg; i++) {
    // Capacity for 5 local refs: jname, jdesc, jtype, jdefStr and obj
    (*env)->PushLocalFrame(env, 5);
    jstring jname, jdesc, jtype, jdefStr;

    jname = (*env)->NewStringUTF(env,dcmd_arg_info_array[i].name);
    POP_EXCEPTION_CHECK_AND_FREE(1, dcmd_arg_info_array);

    jdesc = (*env)->NewStringUTF(env,dcmd_arg_info_array[i].description);
    POP_EXCEPTION_CHECK_AND_FREE(1, dcmd_arg_info_array);

    jtype = (*env)->NewStringUTF(env,dcmd_arg_info_array[i].type);
    POP_EXCEPTION_CHECK_AND_FREE(1, dcmd_arg_info_array);

    jdefStr = (*env)->NewStringUTF(env, dcmd_arg_info_array[i].default_string);
    POP_EXCEPTION_CHECK_AND_FREE(1, dcmd_arg_info_array);
    obj = JNU_NewObjectByName(env,
                              "com/sun/management/internal/DiagnosticCommandArgumentInfo",
                              "(Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;ZZZI)V",
                              jname, jdesc, jtype,
                              dcmd_arg_info_array[i].default_string == NULL ? NULL: jdefStr,
                              dcmd_arg_info_array[i].mandatory,
                              dcmd_arg_info_array[i].option,
                              dcmd_arg_info_array[i].multiple,
                              dcmd_arg_info_array[i].position);
    if (obj == NULL) {
      (*env)->PopLocalFrame(env, NULL);
      free(dcmd_arg_info_array);
      return NULL;
    }
    obj = (*env)->PopLocalFrame(env, obj);
    (*env)->SetObjectArrayElement(env, result, i, obj);
    POP_EXCEPTION_CHECK_AND_FREE(0, dcmd_arg_info_array);
  }
  free(dcmd_arg_info_array);
  arraysCls = (*env)->FindClass(env, "java/util/Arrays");
  if ((*env)->ExceptionCheck(env)) {
    return NULL;
  }
  mid = (*env)->GetStaticMethodID(env, arraysCls,
                                  "asList", "([Ljava/lang/Object;)Ljava/util/List;");
  resultList = (*env)->CallStaticObjectMethod(env, arraysCls, mid, result);
  if ((*env)->ExceptionCheck(env)) {
    // Make sure we return NULL in case of OOM inside Java
    return NULL;
  }
  return resultList;
}

/* Throws IllegalArgumentException if at least one of the diagnostic command
 * passed in argument is not supported by the JVM
 */
JNIEXPORT jobjectArray JNICALL
Java_com_sun_management_internal_DiagnosticCommandImpl_getDiagnosticCommandInfo
(JNIEnv *env, jobject dummy, jobjectArray commands)
{
  int i;
  jclass dcmdInfoCls;
  jobject result;
  jobjectArray args;
  jobject obj;
  jmmOptionalSupport mos;
  jint ret = jmm_interface_management_ext->GetOptionalSupport(env, &mos);
  jsize num_commands;
  dcmdInfo* dcmd_info_array;
  jstring jname, jdesc, jimpact, cmd;

  if (commands == NULL) {
      JNU_ThrowNullPointerException(env, "Invalid String Array");
      return NULL;
  }
  num_commands = (*env)->GetArrayLength(env, commands);
  // Ensure capacity for 2 + num_commands local refs:
  //  2 => dcmdInfoCls, result
  //  num_commmands => one obj per command
  (*env)->PushLocalFrame(env, 2 + num_commands);
  dcmdInfoCls = (*env)->FindClass(env,
                                  "com/sun/management/internal/DiagnosticCommandInfo");
  if ((*env)->ExceptionCheck(env)) {
    (*env)->PopLocalFrame(env, NULL);
    return NULL;
  }

  result = (*env)->NewObjectArray(env, num_commands, dcmdInfoCls, NULL);
  if (result == NULL) {
      (*env)->PopLocalFrame(env, NULL);
      return NULL;
  }
  if (num_commands == 0) {
      result = (*env)->PopLocalFrame(env, result);
      /* Handle the 'zero commands' case specially to avoid calling 'malloc()' */
      /* with a zero argument because that may legally return a NULL pointer.  */
      return result;
  }
  dcmd_info_array = (dcmdInfo*) malloc(num_commands * sizeof(dcmdInfo));
  if (dcmd_info_array == NULL) {
      (*env)->PopLocalFrame(env, NULL);
      JNU_ThrowOutOfMemoryError(env, NULL);
      return NULL;
  }
  jmm_interface_management_ext->GetDiagnosticCommandInfo(env, commands, dcmd_info_array);
  for (i=0; i<num_commands; i++) {
      // Ensure capacity for 6 local refs:
      //  6 => jname, jdesc, jimpact, cmd, args, obj
      (*env)->PushLocalFrame(env, 6);

      cmd = (*env)->GetObjectArrayElement(env, commands, i);
      args = getDiagnosticCommandArgumentInfoArray(env,
                                                   cmd,
                                                   dcmd_info_array[i].num_arguments);
      if (args == NULL) {
          (*env)->PopLocalFrame(env, NULL);
          (*env)->PopLocalFrame(env, NULL);
          free(dcmd_info_array);
          return NULL;
      }

      jname = (*env)->NewStringUTF(env,dcmd_info_array[i].name);
      POP_EXCEPTION_CHECK_AND_FREE(2, dcmd_info_array);

      jdesc = (*env)->NewStringUTF(env,dcmd_info_array[i].description);
      POP_EXCEPTION_CHECK_AND_FREE(2, dcmd_info_array);

      jimpact = (*env)->NewStringUTF(env,dcmd_info_array[i].impact);
      POP_EXCEPTION_CHECK_AND_FREE(2, dcmd_info_array);

      obj = JNU_NewObjectByName(env,
                                "com/sun/management/internal/DiagnosticCommandInfo",
                                "(Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;ZLjava/util/List;)V",
                                jname, jdesc, jimpact,
                                dcmd_info_array[i].enabled,
                                args);
      if (obj == NULL) {
          (*env)->PopLocalFrame(env, NULL);
          (*env)->PopLocalFrame(env, NULL);
          free(dcmd_info_array);
          return NULL;
      }
      obj = (*env)->PopLocalFrame(env, obj);

      (*env)->SetObjectArrayElement(env, result, i, obj);
      POP_EXCEPTION_CHECK_AND_FREE(1, dcmd_info_array);
  }
  result = (*env)->PopLocalFrame(env, result);
  free(dcmd_info_array);
  return result;
}

/* Throws IllegalArgumentException if the diagnostic command
 * passed in argument is not supported by the JVM
 */
JNIEXPORT jstring JNICALL
Java_com_sun_management_internal_DiagnosticCommandImpl_executeDiagnosticCommand
(JNIEnv *env, jobject dummy, jstring command) {
  return jmm_interface_management_ext->ExecuteDiagnosticCommand(env, command);
}