/*

 * Copyright (c) 2018, 2019, Oracle and/or its affiliates. All rights reserved.

 * Copyright (c) 2018, 2019, Google 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.

 */

#include <stdlib.h>

#include <string.h>

#include "ExceptionCheckingJniEnv.hpp"

#include "nsk_tools.h"

namespace {

static const char* get_dirname(const char* fullname) {

  const char* p;

  const char* base = fullname;;

  if (fullname == NULL) {

    return NULL;

  }

  for (p = fullname; *p != '\0'; p++) {

    if (*p == '/' || *p == '\\') {

      base = p + 1;

    }

  }

  return base;

}

template<class T = void*>

class JNIVerifier {

 public:

  JNIVerifier(ExceptionCheckingJniEnv *env, const char* base_message,

              int line, const char* file)

      : _env(env), _base_message(base_message), _error_message(NULL),

        _line(line), _file(get_dirname(file)) {

  }

  // Until C++11 is supported, we have to write multiple template constructors.

  template <typename U>

  JNIVerifier(ExceptionCheckingJniEnv *env, const char* base_message,

              U parameter,

              int line, const char* file)

      : _env(env), _base_message(base_message), _error_message(NULL),

        _line(line), _file(get_dirname(file)) {

          PrintPreCall(parameter);

  }

  template <typename U, typename V>

  JNIVerifier(ExceptionCheckingJniEnv *env, const char* base_message,

              U parameter1,

              V parameter2,

              int line, const char* file)

      : _env(env), _base_message(base_message), _error_message(NULL),

        _line(line), _file(get_dirname(file)) {

          PrintPreCall(parameter1, parameter2);

  }

  template <typename U, typename V, typename W>

  JNIVerifier(ExceptionCheckingJniEnv *env, const char* base_message,

              U parameter1, V parameter2, W parameter3,

              int line, const char* file)

      : _env(env), _base_message(base_message), _error_message(NULL),

        _line(line), _file(get_dirname(file)) {

          PrintPreCall(parameter1, parameter2, parameter3);

  }

  ~JNIVerifier() {

    PrintPostCall();

    JNIEnv* jni_env = _env->GetJNIEnv();

    if (jni_env->ExceptionCheck() && !_error_message) {

      _error_message = "internal error";

    }

    if (_error_message != NULL) {

      GenerateErrorMessage();

    }

  }

  int DecimalToAsciiRec(char *str, long line) {

    if (line == 0) {

      return 0;

    }

    int remainder = line % 10;

    long quotient = line / 10;

    int pos = DecimalToAsciiRec(str, quotient);

    str[pos] = '0' + remainder;

    return pos + 1;

  }

  // Implementing a simple version of sprintf for "%d"...

  void DecimalToAscii(char *str, int line) {

    // Go to long so that the INT_MIN case can be handled seemlessly.

    long internal_line = line;

    if (internal_line == 0) {

      str[0] = '0';

      str[1] = '\0';

      return;

    }

    if (internal_line < 0) {

      *str = '-';

      internal_line *= -1;

      str++;

    }

    str[DecimalToAsciiRec(str, internal_line)] = '\0';

  }

  void GenerateErrorMessage() {

    // This is error prone, but:

    //   - Seems like we cannot use std::string (due to windows/solaris not

    //   building when used, seemingly due to exception libraries not linking).

    //   - Seems like we cannot use sprintf due to VS2013 (JDK-8213622).

    //

    //   We are aiming to do:

    //     snprintf(full_message, len, "JNI method %s : %s from %s : %d", _base_message, _error_message,

    //              _file, _line);

    //   but will use strlen + memcpy instead.

    const char* pre_message = "JNI method ";

    const char* between_msg = " : ";

    const char* from_msg = " from ";

    const char* file_name = _file ? _file : "Unknown File";

    const char* strs[] = {

      pre_message,

      _base_message,

      between_msg,

      _error_message,

      from_msg,

      file_name,

      between_msg,

    };

    size_t msg_number = sizeof(strs) / sizeof(strs[0]);

    size_t len = 0;

    for (size_t i = 0; i < msg_number; i++) {

      len += strlen(strs[i]);

    }

    // 32-bit signed means 11 characters due to the '-'.

    const int MAX_INTEGER_DIGITS = 11;

    // Add for the line number and 1 for the '\0'.

    len += MAX_INTEGER_DIGITS + 1;

    char* full_message = (char*) malloc(len);

    if (full_message == NULL) {

      _env->HandleError(_error_message);

      return;

    }

    // Now we construct the string using strcat to not use sprintf/std::string

    // instead of:

    //     snprintf(full_message, len, "JNI method %s : %s from %s:%d", _base_message,

    //         _error_message, _file, _line);

    full_message[0] = '\0';

    for (size_t i = 0; i < msg_number; i++) {

      strcat(full_message, strs[i]);

    }

    if (strlen(full_message) >= len) {

      _env->GetJNIEnv()->FatalError("Final length of message is not what was expected");

    }

    _env->HandleError(full_message);

    free(full_message);

  }

  T ResultNotNull(T ptr) {

    if (ptr == NULL) {

      _error_message = "Return is NULL";

    }

    return ptr;

  }

  T ResultIsZero(T value) {

    if (value != 0) {

      _error_message = "Return is not zero";

    }

    return value;

  }

  void PrintPreCallHeader() {

    if (!nsk_getVerboseMode()) {

      return;

    }

    fprintf(stdout, ">> Calling JNI method %s from %s:%d\n",

            _base_message, _file, _line);

    fprintf(stdout, ">> Calling with these parameter(s):\n");

  }

  // Until we can actually link with C++ more uniformely across architectures,

  // we have to do this...

  template<class U>

  void PrintParameter(U* ptr) {

    fprintf(stdout, "\t%p\n", ptr);

  }

  void PrintParameter(int value) {

    fprintf(stdout, "\t%d\n", value);

  }

  // Until C++11 is supported, we have to write multiple PrintPreCall.

  template<class U>

  void PrintPreCall(U first_parameter) {

    if (!nsk_getVerboseMode()) {

      return;

    }

    PrintPreCallHeader();

    PrintParameter(first_parameter);

  }

  template<class U, class V>

  void PrintPreCall(U parameter1, V parameter2) {

    if (!nsk_getVerboseMode()) {

      return;

    }

    PrintPreCallHeader();

    PrintParameter(parameter1);

    PrintParameter(parameter2);

  }

  template<class U, class V, class W>

  void PrintPreCall(U parameter1, V parameter2, W parameter3) {

    if (!nsk_getVerboseMode()) {

      return;

    }

    PrintPreCallHeader();

    PrintParameter(parameter1);

    PrintParameter(parameter2);

    PrintParameter(parameter3);

  }

  void PrintPostCall() {

    if (!nsk_getVerboseMode()) {

      return;

    }

    fprintf(stderr, "<< Called JNI method %s from %s:%d\n",

            _base_message, _file, _line);

  }

 private:

  ExceptionCheckingJniEnv* _env;

  const char* const _base_message;

  const char* _error_message;

  int _line;

  const char* const _file;

};

}

jclass ExceptionCheckingJniEnv::FindClass(const char *class_name,

                                          int line, const char* file_name) {

  JNIVerifier<jclass> marker(this, "FindClass", class_name, line, file_name);

  return marker.ResultNotNull(_jni_env->FindClass(class_name));

}

jint ExceptionCheckingJniEnv::RegisterNatives(jclass clazz,

                                              const JNINativeMethod *methods,

                                              jint nMethods,

                                              int line,

                                              const char* file_name) {

  JNIVerifier<jint> marker(this, "RegisterNatives", methods, nMethods, line, file_name);

  return marker.ResultIsZero(_jni_env->RegisterNatives(clazz, methods, nMethods));

}

jclass ExceptionCheckingJniEnv::GetObjectClass(jobject obj, int line,

                                               const char* file_name) {

  JNIVerifier<jclass> marker(this, "GetObjectClass", obj, line, file_name);

  return marker.ResultNotNull(_jni_env->GetObjectClass(obj));

}

jfieldID ExceptionCheckingJniEnv::GetStaticFieldID(jclass klass, const char *name,

                                                   const char* type,

                                                   int line, const char* file_name) {

  JNIVerifier<jfieldID> marker(this, "GetStaticFieldID", klass, name, type,

                               line, file_name);

  return marker.ResultNotNull(_jni_env->GetStaticFieldID(klass, name, type));

}

jfieldID ExceptionCheckingJniEnv::GetFieldID(jclass klass, const char *name,

                                             const char* type,

                                             int line, const char* file_name) {

  JNIVerifier<jfieldID> marker(this, "GetFieldID", klass, name, type, line, file_name);

  return marker.ResultNotNull(_jni_env->GetFieldID(klass, name, type));

}

jobject ExceptionCheckingJniEnv::GetStaticObjectField(jclass klass, jfieldID field,

                                                      int line, const char* file_name) {

  JNIVerifier<jobject> marker(this, "GetStaticObjectField", klass, field,

                              line, file_name);

  return marker.ResultNotNull(_jni_env->GetStaticObjectField(klass, field));

}

jobject ExceptionCheckingJniEnv::GetObjectField(jobject obj, jfieldID field,

                                                int line, const char* file_name) {

  JNIVerifier<jobject> marker(this, "GetObjectField", obj, field, line, file_name);

  return marker.ResultNotNull(_jni_env->GetObjectField(obj, field));

}

void ExceptionCheckingJniEnv::SetObjectField(jobject obj, jfieldID field, jobject value,

                                             int line, const char* file_name) {

  JNIVerifier<> marker(this, "SetObjectField", obj, field, value, line, file_name);

  _jni_env->SetObjectField(obj, field, value);

}

jobject ExceptionCheckingJniEnv::NewGlobalRef(jobject obj, int line, const char* file_name) {

  JNIVerifier<jobject> marker(this, "NewGlobalRef", obj, line, file_name);

  return marker.ResultNotNull(_jni_env->NewGlobalRef(obj));

}

void ExceptionCheckingJniEnv::DeleteGlobalRef(jobject obj, int line, const char* file_name) {

  JNIVerifier<> marker(this, "DeleteGlobalRef", obj, line, file_name);

  _jni_env->DeleteGlobalRef(obj);

}

jobject ExceptionCheckingJniEnv::NewLocalRef(jobject obj, int line, const char* file_name) {

  JNIVerifier<jobject> marker(this, "NewLocalRef", obj, line, file_name);

  return marker.ResultNotNull(_jni_env->NewLocalRef(obj));

}

void ExceptionCheckingJniEnv::DeleteLocalRef(jobject obj, int line, const char* file_name) {

  JNIVerifier<> marker(this, "DeleteLocalRef", obj, line, file_name);

  _jni_env->DeleteLocalRef(obj);

}

jweak ExceptionCheckingJniEnv::NewWeakGlobalRef(jobject obj, int line, const char* file_name) {

  JNIVerifier<jweak> marker(this, "NewWeakGlobalRef", obj, line, file_name);

  return marker.ResultNotNull(_jni_env->NewWeakGlobalRef(obj));

}

void ExceptionCheckingJniEnv::DeleteWeakGlobalRef(jweak weak_ref, int line, const char* file_name) {

  JNIVerifier<> marker(this, "DeleteWeakGlobalRef", weak_ref, line, file_name);

  _jni_env->DeleteWeakGlobalRef(weak_ref);

}

jsize ExceptionCheckingJniEnv::GetArrayLength(jarray array, int line, const char* file_name) {

  JNIVerifier<> marker(this, "GetArrayLength", array, line, file_name);

  return _jni_env->GetArrayLength(array);

}

jsize ExceptionCheckingJniEnv::GetStringLength(jstring str, int line, const char* file_name) {

  JNIVerifier<> marker(this, "GetStringLength", str, line, file_name);

  return _jni_env->GetStringLength(str);

}

void* ExceptionCheckingJniEnv::GetPrimitiveArrayCritical(jarray array, jboolean* is_copy,

                                                         int line, const char* file_name) {

  JNIVerifier<> marker(this, "GetPrimitiveArrayCritical", array, is_copy, line, file_name);

  return marker.ResultNotNull(_jni_env->GetPrimitiveArrayCritical(array, is_copy));

}

void ExceptionCheckingJniEnv::ReleasePrimitiveArrayCritical(jarray array, void* carray, jint mode,

                                                            int line, const char* file_name) {

  JNIVerifier<> marker(this, "ReleasePrimitiveArrayCritical", array, carray, mode,

                       line, file_name);

  _jni_env->ReleasePrimitiveArrayCritical(array, carray, mode);

}

const jchar* ExceptionCheckingJniEnv::GetStringCritical(jstring str, jboolean* is_copy,

                                                        int line, const char* file_name) {

  JNIVerifier<const jchar*> marker(this, "GetPrimitiveArrayCritical", str, is_copy,

                                   line, file_name);

  return marker.ResultNotNull(_jni_env->GetStringCritical(str, is_copy));

}

void ExceptionCheckingJniEnv::ReleaseStringCritical(jstring str, const jchar* carray,

                                                    int line, const char* file_name) {

  JNIVerifier<> marker(this, "ReleaseStringCritical", str, carray, line, file_name);

  _jni_env->ReleaseStringCritical(str, carray);

}

jbyte* ExceptionCheckingJniEnv::GetByteArrayElements(jbyteArray array, jboolean* is_copy,

                                                   int line, const char* file_name) {

  JNIVerifier<jbyte*> marker(this, "GetByteArrayElements", array, is_copy, line, file_name);

  return marker.ResultNotNull(_jni_env->GetByteArrayElements(array, is_copy));

}

void ExceptionCheckingJniEnv::ReleaseByteArrayElements(jbyteArray array, jbyte* byte_array, jint mode,

                                                       int line, const char* file_name) {

  JNIVerifier<> marker(this, "ReleaseByteArrayElements", array, byte_array, mode,

                       line, file_name);

  _jni_env->ReleaseByteArrayElements(array, byte_array, mode);

}

jmethodID ExceptionCheckingJniEnv::GetMethodID(jclass klass, const char* name, const char* sig,

                                               int line, const char* file_name) {

  JNIVerifier<jmethodID> marker(this, "GetMethodID", klass, name, sig, line, file_name);

  return marker.ResultNotNull(_jni_env->GetMethodID(klass, name, sig));

}

jobject ExceptionCheckingJniEnv::NewObject(jclass klass, jmethodID methodID,

                                           int line, const char* file_name, ...) {

  // In the case of NewObject, we miss the extra arguments passed to NewObject sadly.

  JNIVerifier<jobject> marker(this, "NewObject", klass, methodID, line, file_name);

  va_list args;

  va_start(args, file_name);

  jobject result = marker.ResultNotNull(_jni_env->NewObjectV(klass, methodID, args));

  va_end(args);

  return result;

}