/*

 * Copyright (c) 2005, 2010, 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.

 *

 */

#include "precompiled.hpp"

#include "classfile/symbolTable.hpp"

#include "interpreter/bytecodeStream.hpp"

#include "prims/jvmtiClassFileReconstituter.hpp"

#include "runtime/signature.hpp"

#ifdef TARGET_ARCH_x86

# include "bytes_x86.hpp"

#endif

#ifdef TARGET_ARCH_sparc

# include "bytes_sparc.hpp"

#endif

#ifdef TARGET_ARCH_zero

# include "bytes_zero.hpp"

#endif

// FIXME: add Deprecated, LVT, LVTT attributes

// FIXME: fix Synthetic attribute

// FIXME: per Serguei, add error return handling for constantPoolOopDesc::copy_cpool_bytes()

// Write the field information portion of ClassFile structure

// JVMSpec|     u2 fields_count;

// JVMSpec|     field_info fields[fields_count];

void JvmtiClassFileReconstituter::write_field_infos() {

  HandleMark hm(thread());

  typeArrayHandle fields(thread(), ikh()->fields());

  int fields_length = fields->length();

  int num_fields = fields_length / instanceKlass::next_offset;

  objArrayHandle fields_anno(thread(), ikh()->fields_annotations());

  write_u2(num_fields);

  for (int index = 0; index < fields_length; index += instanceKlass::next_offset) {

    AccessFlags access_flags;

    int flags = fields->ushort_at(index + instanceKlass::access_flags_offset);

    access_flags.set_flags(flags);

    int name_index = fields->ushort_at(index + instanceKlass::name_index_offset);

    int signature_index = fields->ushort_at(index + instanceKlass::signature_index_offset);

    int initial_value_index = fields->ushort_at(index + instanceKlass::initval_index_offset);

    guarantee(name_index != 0 && signature_index != 0, "bad constant pool index for field");

    int offset = ikh()->offset_from_fields( index );

    int generic_signature_index =

                        fields->ushort_at(index + instanceKlass::generic_signature_offset);

    typeArrayHandle anno(thread(), fields_anno.not_null() ?

                                 (typeArrayOop)(fields_anno->obj_at(index / instanceKlass::next_offset)) :

                                 (typeArrayOop)NULL);

    // JVMSpec|   field_info {

    // JVMSpec|         u2 access_flags;

    // JVMSpec|         u2 name_index;

    // JVMSpec|         u2 descriptor_index;

    // JVMSpec|         u2 attributes_count;

    // JVMSpec|         attribute_info attributes[attributes_count];

    // JVMSpec|   }

    write_u2(flags & JVM_RECOGNIZED_FIELD_MODIFIERS);

    write_u2(name_index);

    write_u2(signature_index);

    int attr_count = 0;

    if (initial_value_index != 0) {

      ++attr_count;

    }

    if (access_flags.is_synthetic()) {

      // ++attr_count;

    }

    if (generic_signature_index != 0) {

      ++attr_count;

    }

    if (anno.not_null()) {

      ++attr_count;     // has RuntimeVisibleAnnotations attribute

    }

    write_u2(attr_count);

    if (initial_value_index != 0) {

      write_attribute_name_index("ConstantValue");

      write_u4(2); //length always 2

      write_u2(initial_value_index);

    }

    if (access_flags.is_synthetic()) {

      // write_synthetic_attribute();

    }

    if (generic_signature_index != 0) {

      write_signature_attribute(generic_signature_index);

    }

    if (anno.not_null()) {

      write_annotations_attribute("RuntimeVisibleAnnotations", anno);

    }

  }

}

// Write Code attribute

// JVMSpec|   Code_attribute {

// JVMSpec|     u2 attribute_name_index;

// JVMSpec|     u4 attribute_length;

// JVMSpec|     u2 max_stack;

// JVMSpec|     u2 max_locals;

// JVMSpec|     u4 code_length;

// JVMSpec|     u1 code[code_length];

// JVMSpec|     u2 exception_table_length;

// JVMSpec|     {       u2 start_pc;

// JVMSpec|             u2 end_pc;

// JVMSpec|             u2  handler_pc;

// JVMSpec|             u2  catch_type;

// JVMSpec|     }       exception_table[exception_table_length];

// JVMSpec|     u2 attributes_count;

// JVMSpec|     attribute_info attributes[attributes_count];

// JVMSpec|   }

void JvmtiClassFileReconstituter::write_code_attribute(methodHandle method) {

  constMethodHandle const_method(thread(), method->constMethod());

  u2 line_num_cnt = 0;

  int stackmap_len = 0;

  // compute number and length of attributes -- FIXME: for now no LVT

  int attr_count = 0;

  int attr_size = 0;

  if (const_method->has_linenumber_table()) {

    line_num_cnt = line_number_table_entries(method);

    if (line_num_cnt != 0) {

      ++attr_count;

      // Compute the complete size of the line number table attribute:

      //      LineNumberTable_attribute {

      //        u2 attribute_name_index;

      //        u4 attribute_length;

      //        u2 line_number_table_length;

      //        {  u2 start_pc;

      //           u2 line_number;

      //        } line_number_table[line_number_table_length];

      //      }

      attr_size += 2 + 4 + 2 + line_num_cnt * (2 + 2);

    }

  }

  if (method->has_stackmap_table()) {

    stackmap_len = method->stackmap_data()->length();

    if (stackmap_len != 0) {

      ++attr_count;

      // Compute the  size of the stack map table attribute (VM stores raw):

      //      StackMapTable_attribute {

      //        u2 attribute_name_index;

      //        u4 attribute_length;

      //        u2 number_of_entries;

      //        stack_map_frame_entries[number_of_entries];

      //      }

      attr_size += 2 + 4 + stackmap_len;

    }

  }

  typeArrayHandle exception_table(thread(), const_method->exception_table());

  int exception_table_length = exception_table->length();

  int exception_table_entries = exception_table_length / 4;

  int code_size = const_method->code_size();

  int size =

    2+2+4 +                                // max_stack, max_locals, code_length

    code_size +                            // code

    2 +                                    // exception_table_length

    (2+2+2+2) * exception_table_entries +  // exception_table

    2 +                                    // attributes_count

    attr_size;                             // attributes

  write_attribute_name_index("Code");

  write_u4(size);

  write_u2(method->max_stack());

  write_u2(method->max_locals());

  write_u4(code_size);

  copy_bytecodes(method, (unsigned char*)writeable_address(code_size));

  write_u2(exception_table_entries);

  for (int index = 0; index < exception_table_length; ) {

    write_u2(exception_table->int_at(index++));

    write_u2(exception_table->int_at(index++));

    write_u2(exception_table->int_at(index++));

    write_u2(exception_table->int_at(index++));

  }

  write_u2(attr_count);

  if (line_num_cnt != 0) {

    write_line_number_table_attribute(method, line_num_cnt);

  }

  if (stackmap_len != 0) {

    write_stackmap_table_attribute(method, stackmap_len);

  }

  // FIXME: write LVT attribute

}

// Write Exceptions attribute

// JVMSpec|   Exceptions_attribute {

// JVMSpec|     u2 attribute_name_index;

// JVMSpec|     u4 attribute_length;

// JVMSpec|     u2 number_of_exceptions;

// JVMSpec|     u2 exception_index_table[number_of_exceptions];

// JVMSpec|   }

void JvmtiClassFileReconstituter::write_exceptions_attribute(constMethodHandle const_method) {

  CheckedExceptionElement* checked_exceptions = const_method->checked_exceptions_start();

  int checked_exceptions_length = const_method->checked_exceptions_length();

  int size =

    2 +                                    // number_of_exceptions

    2 * checked_exceptions_length;         // exception_index_table

  write_attribute_name_index("Exceptions");

  write_u4(size);

  write_u2(checked_exceptions_length);

  for (int index = 0; index < checked_exceptions_length; index++) {

    write_u2(checked_exceptions[index].class_cp_index);

  }

}

// Write SourceFile attribute

// JVMSpec|   SourceFile_attribute {

// JVMSpec|     u2 attribute_name_index;

// JVMSpec|     u4 attribute_length;

// JVMSpec|     u2 sourcefile_index;

// JVMSpec|   }

void JvmtiClassFileReconstituter::write_source_file_attribute() {

  assert(ikh()->source_file_name() != NULL, "caller must check");

  write_attribute_name_index("SourceFile");

  write_u4(2);  // always length 2

  write_u2(symbol_to_cpool_index(ikh()->source_file_name()));

}

// Write SourceDebugExtension attribute

// JSR45|   SourceDebugExtension_attribute {

// JSR45|       u2 attribute_name_index;

// JSR45|       u4 attribute_length;

// JSR45|       u2 sourcefile_index;

// JSR45|   }

void JvmtiClassFileReconstituter::write_source_debug_extension_attribute() {

  assert(ikh()->source_debug_extension() != NULL, "caller must check");

  write_attribute_name_index("SourceDebugExtension");

  write_u4(2);  // always length 2

  write_u2(symbol_to_cpool_index(ikh()->source_debug_extension()));

}

// Write (generic) Signature attribute

// JVMSpec|   Signature_attribute {

// JVMSpec|     u2 attribute_name_index;

// JVMSpec|     u4 attribute_length;

// JVMSpec|     u2 signature_index;

// JVMSpec|   }

void JvmtiClassFileReconstituter::write_signature_attribute(u2 generic_signature_index) {

  write_attribute_name_index("Signature");

  write_u4(2);  // always length 2

  write_u2(generic_signature_index);

}

// Compute the number of entries in the InnerClasses attribute

u2 JvmtiClassFileReconstituter::inner_classes_attribute_length() {

  typeArrayOop inner_class_list = ikh()->inner_classes();

  return (inner_class_list == NULL) ? 0 : inner_class_list->length();

}

// Write an annotation attribute.  The VM stores them in raw form, so all we need

// to do is add the attrubute name and fill in the length.

// JSR202|   *Annotations_attribute {

// JSR202|     u2 attribute_name_index;

// JSR202|     u4 attribute_length;

// JSR202|     ...

// JSR202|   }

void JvmtiClassFileReconstituter::write_annotations_attribute(const char* attr_name,

                                                              typeArrayHandle annos) {

  u4 length = annos->length();

  write_attribute_name_index(attr_name);

  write_u4(length);

  memcpy(writeable_address(length), annos->byte_at_addr(0), length);

}

// Write InnerClasses attribute

// JVMSpec|   InnerClasses_attribute {

// JVMSpec|     u2 attribute_name_index;

// JVMSpec|     u4 attribute_length;

// JVMSpec|     u2 number_of_classes;

// JVMSpec|     {  u2 inner_class_info_index;

// JVMSpec|        u2 outer_class_info_index;

// JVMSpec|        u2 inner_name_index;

// JVMSpec|        u2 inner_class_access_flags;

// JVMSpec|     } classes[number_of_classes];

// JVMSpec|   }

void JvmtiClassFileReconstituter::write_inner_classes_attribute(int length) {

  typeArrayOop inner_class_list = ikh()->inner_classes();

  guarantee(inner_class_list != NULL && inner_class_list->length() == length,

            "caller must check");

  typeArrayHandle inner_class_list_h(thread(), inner_class_list);

  assert (length % instanceKlass::inner_class_next_offset == 0, "just checking");

  u2 entry_count = length / instanceKlass::inner_class_next_offset;

  u4 size = 2 + entry_count * (2+2+2+2);

  write_attribute_name_index("InnerClasses");

  write_u4(size);

  write_u2(entry_count);

  for (int i = 0; i < length; i += instanceKlass::inner_class_next_offset) {

    write_u2(inner_class_list_h->ushort_at(

                      i + instanceKlass::inner_class_inner_class_info_offset));

    write_u2(inner_class_list_h->ushort_at(

                      i + instanceKlass::inner_class_outer_class_info_offset));

    write_u2(inner_class_list_h->ushort_at(

                      i + instanceKlass::inner_class_inner_name_offset));

    write_u2(inner_class_list_h->ushort_at(

                      i + instanceKlass::inner_class_access_flags_offset));

  }

}

// Write Synthetic attribute

// JVMSpec|   Synthetic_attribute {

// JVMSpec|     u2 attribute_name_index;

// JVMSpec|     u4 attribute_length;

// JVMSpec|   }

void JvmtiClassFileReconstituter::write_synthetic_attribute() {

  write_attribute_name_index("Synthetic");

  write_u4(0); //length always zero

}

// Compute size of LineNumberTable

u2 JvmtiClassFileReconstituter::line_number_table_entries(methodHandle method) {

  // The line number table is compressed so we don't know how big it is until decompressed.

  // Decompression is really fast so we just do it twice.

  u2 num_entries = 0;

  CompressedLineNumberReadStream stream(method->compressed_linenumber_table());

  while (stream.read_pair()) {

    num_entries++;

  }

  return num_entries;

}

// Write LineNumberTable attribute

// JVMSpec|   LineNumberTable_attribute {

// JVMSpec|     u2 attribute_name_index;

// JVMSpec|     u4 attribute_length;

// JVMSpec|     u2 line_number_table_length;

// JVMSpec|     {  u2 start_pc;

// JVMSpec|        u2 line_number;

// JVMSpec|     } line_number_table[line_number_table_length];

// JVMSpec|   }

void JvmtiClassFileReconstituter::write_line_number_table_attribute(methodHandle method,

                                                                    u2 num_entries) {

  write_attribute_name_index("LineNumberTable");

  write_u4(2 + num_entries * (2 + 2));

  write_u2(num_entries);

  CompressedLineNumberReadStream stream(method->compressed_linenumber_table());

  while (stream.read_pair()) {

    write_u2(stream.bci());

    write_u2(stream.line());

  }

}

// Write stack map table attribute

// JSR-202|   StackMapTable_attribute {

// JSR-202|     u2 attribute_name_index;

// JSR-202|     u4 attribute_length;

// JSR-202|     u2 number_of_entries;

// JSR-202|     stack_map_frame_entries[number_of_entries];

// JSR-202|   }

void JvmtiClassFileReconstituter::write_stackmap_table_attribute(methodHandle method,

                                                                 int stackmap_len) {

  write_attribute_name_index("StackMapTable");

  write_u4(stackmap_len);

  memcpy(

    writeable_address(stackmap_len),

    (void*)(method->stackmap_data()->byte_at_addr(0)),

    stackmap_len);

}

// Write one method_info structure

// JVMSpec|   method_info {

// JVMSpec|     u2 access_flags;

// JVMSpec|     u2 name_index;

// JVMSpec|     u2 descriptor_index;

// JVMSpec|     u2 attributes_count;

// JVMSpec|     attribute_info attributes[attributes_count];

// JVMSpec|   }

void JvmtiClassFileReconstituter::write_method_info(methodHandle method) {

  AccessFlags access_flags = method->access_flags();

  constMethodHandle const_method(thread(), method->constMethod());

  u2 generic_signature_index = const_method->generic_signature_index();

  typeArrayHandle anno(thread(), method->annotations());

  typeArrayHandle param_anno(thread(), method->parameter_annotations());

  typeArrayHandle default_anno(thread(), method->annotation_default());

  write_u2(access_flags.get_flags() & JVM_RECOGNIZED_METHOD_MODIFIERS);

  write_u2(const_method->name_index());

  write_u2(const_method->signature_index());

  // write attributes in the same order javac does, so we can test with byte for

  // byte comparison

  int attr_count = 0;

  if (const_method->code_size() != 0) {

    ++attr_count;     // has Code attribute

  }

  if (const_method->has_checked_exceptions()) {

    ++attr_count;     // has Exceptions attribute

  }

  if (default_anno.not_null()) {

    ++attr_count;     // has AnnotationDefault attribute

  }

  // Deprecated attribute would go here

  if (access_flags.is_synthetic()) { // FIXME

    // ++attr_count;

  }

  if (generic_signature_index != 0) {

    ++attr_count;

  }

  if (anno.not_null()) {

    ++attr_count;     // has RuntimeVisibleAnnotations attribute

  }

  if (param_anno.not_null()) {

    ++attr_count;     // has RuntimeVisibleParameterAnnotations attribute

  }

  write_u2(attr_count);

  if (const_method->code_size() > 0) {

    write_code_attribute(method);

  }

  if (const_method->has_checked_exceptions()) {

    write_exceptions_attribute(const_method);

  }

  if (default_anno.not_null()) {

    write_annotations_attribute("AnnotationDefault", default_anno);

  }

  // Deprecated attribute would go here

  if (access_flags.is_synthetic()) {

    // write_synthetic_attribute();

  }

  if (generic_signature_index != 0) {

    write_signature_attribute(generic_signature_index);

  }

  if (anno.not_null()) {

    write_annotations_attribute("RuntimeVisibleAnnotations", anno);

  }

  if (param_anno.not_null()) {

    write_annotations_attribute("RuntimeVisibleParameterAnnotations", param_anno);

  }

}

// Write the class attributes portion of ClassFile structure

// JVMSpec|     u2 attributes_count;

// JVMSpec|     attribute_info attributes[attributes_count];

void JvmtiClassFileReconstituter::write_class_attributes() {

  u2 inner_classes_length = inner_classes_attribute_length();

  symbolHandle generic_signature(thread(), ikh()->generic_signature());

  typeArrayHandle anno(thread(), ikh()->class_annotations());

  int attr_count = 0;

  if (generic_signature() != NULL) {

    ++attr_count;

  }

  if (ikh()->source_file_name() != NULL) {

    ++attr_count;

  }

  if (ikh()->source_debug_extension() != NULL) {

    ++attr_count;

  }

  if (inner_classes_length > 0) {

    ++attr_count;

  }

  if (anno.not_null()) {

    ++attr_count;     // has RuntimeVisibleAnnotations attribute

  }

  write_u2(attr_count);

  if (generic_signature() != NULL) {

    write_signature_attribute(symbol_to_cpool_index(generic_signature()));

  }

  if (ikh()->source_file_name() != NULL) {

    write_source_file_attribute();

  }

  if (ikh()->source_debug_extension() != NULL) {

    write_source_debug_extension_attribute();

  }

  if (inner_classes_length > 0) {

    write_inner_classes_attribute(inner_classes_length);

  }

  if (anno.not_null()) {

    write_annotations_attribute("RuntimeVisibleAnnotations", anno);

  }

}

// Write the method information portion of ClassFile structure

// JVMSpec|     u2 methods_count;

// JVMSpec|     method_info methods[methods_count];

void JvmtiClassFileReconstituter::write_method_infos() {

  HandleMark hm(thread());

  objArrayHandle methods(thread(), ikh()->methods());

  int num_methods = methods->length();

  write_u2(num_methods);

  if (JvmtiExport::can_maintain_original_method_order()) {

    int index;

    int original_index;

    int* method_order = NEW_RESOURCE_ARRAY(int, num_methods);

    // invert the method order mapping

    for (index = 0; index < num_methods; index++) {

      original_index = ikh()->method_ordering()->int_at(index);

      assert(original_index >= 0 && original_index < num_methods,

             "invalid original method index");

      method_order[original_index] = index;

    }

    // write in original order

    for (original_index = 0; original_index < num_methods; original_index++) {

      index = method_order[original_index];