/*

 * Copyright (c) 2003, 2019, 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_MEMORY_FILEMAP_HPP

#define SHARE_MEMORY_FILEMAP_HPP

#include "classfile/classLoader.hpp"

#include "include/cds.h"

#include "memory/metaspaceShared.hpp"

#include "memory/metaspace.hpp"

#include "oops/compressedOops.hpp"

#include "utilities/align.hpp"

// Layout of the file:

//  header: dump of archive instance plus versioning info, datestamp, etc.

//   [magic # = 0xF00BABA2]

//  ... padding to align on page-boundary

//  read-write space

//  read-only space

//  misc data (block offset table, string table, symbols, dictionary, etc.)

//  tag(666)

static const int JVM_IDENT_MAX = 256;

class SharedClassPathEntry {

  enum {

    modules_image_entry,

    jar_entry,

    signed_jar_entry,

    dir_entry,

    unknown_entry

  };

protected:

  u1     _type;

  time_t _timestamp;          // jar timestamp,  0 if is directory, modules image or other

  long   _filesize;           // jar/jimage file size, -1 if is directory, -2 if other

  Array<char>* _name;

  Array<u1>*   _manifest;

public:

  void init(const char* name, bool is_modules_image, TRAPS);

  void metaspace_pointers_do(MetaspaceClosure* it);

  bool validate(bool is_class_path = true);

  // The _timestamp only gets set for jar files.

  bool has_timestamp() {

    return _timestamp != 0;

  }

  bool is_dir()            { return _type == dir_entry; }

  bool is_modules_image()  { return _type == modules_image_entry; }

  bool is_jar()            { return _type == jar_entry; }

  bool is_signed()         { return _type == signed_jar_entry; }

  void set_is_signed()     {

    _type = signed_jar_entry;

  }

  time_t timestamp() const { return _timestamp; }

  long   filesize()  const { return _filesize; }

  const char* name() const { return _name->data(); }

  const char* manifest() const {

    return (_manifest == NULL) ? NULL : (const char*)_manifest->data();

  }

  int manifest_size() const {

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

  }

  void set_manifest(Array<u1>* manifest) {

    _manifest = manifest;

  }

};

struct ArchiveHeapOopmapInfo {

  address _oopmap;               // bitmap for relocating embedded oops

  size_t  _oopmap_size_in_bits;

};

struct FileMapHeader : public CDSFileMapHeaderBase {

  size_t _alignment;                // how shared archive should be aligned

  int    _obj_alignment;            // value of ObjectAlignmentInBytes

  address _narrow_oop_base;         // compressed oop encoding base

  int    _narrow_oop_shift;         // compressed oop encoding shift

  bool    _compact_strings;         // value of CompactStrings

  uintx  _max_heap_size;            // java max heap size during dumping

  CompressedOops::Mode _narrow_oop_mode; // compressed oop encoding mode

  int     _narrow_klass_shift;      // save narrow klass base and shift

  address _narrow_klass_base;

  char*   _misc_data_patching_start;

  char*   _read_only_tables_start;

  address _cds_i2i_entry_code_buffers;

  size_t  _cds_i2i_entry_code_buffers_size;

  size_t  _core_spaces_size;        // number of bytes allocated by the core spaces

                                    // (mc, md, ro, rw and od).

  MemRegion _heap_reserved;         // reserved region for the entire heap at dump time.

  // The following fields are all sanity checks for whether this archive

  // will function correctly with this JVM and the bootclasspath it's

  // invoked with.

  char  _jvm_ident[JVM_IDENT_MAX];      // identifier for jvm

  // The _paths_misc_info is a variable-size structure that records "miscellaneous"

  // information during dumping. It is generated and validated by the

  // SharedPathsMiscInfo class. See SharedPathsMiscInfo.hpp for

  // detailed description.

  //

  // The _paths_misc_info data is stored as a byte array in the archive file header,

  // immediately after the _header field. This information is used only when

  // checking the validity of the archive and is deallocated after the archive is loaded.

  //

  // Note that the _paths_misc_info does NOT include information for JAR files

  // that existed during dump time. Their information is stored in _shared_path_table.

  int _paths_misc_info_size;

  // The following is a table of all the class path entries that were used

  // during dumping. At run time, we require these files to exist and have the same

  // size/modification time, or else the archive will refuse to load.

  //

  // All of these entries must be JAR files. The dumping process would fail if a non-empty

  // directory was specified in the classpaths. If an empty directory was specified

  // it is checked by the _paths_misc_info as described above.

  //

  // FIXME -- if JAR files in the tail of the list were specified but not used during dumping,

  // they should be removed from this table, to save space and to avoid spurious

  // loading failures during runtime.

  jshort _app_class_paths_start_index;  // Index of first app classpath entry

  jshort _app_module_paths_start_index; // Index of first module path entry

  jshort _max_used_path_index;          // max path index referenced during CDS dump

  bool   _verify_local;                 // BytecodeVerificationLocal setting

  bool   _verify_remote;                // BytecodeVerificationRemote setting

  bool   _has_platform_or_app_classes;  // Archive contains app classes

  size_t _shared_base_address;          // SharedBaseAddress used at dump time

  bool   _allow_archiving_with_java_agent; // setting of the AllowArchivingWithJavaAgent option

  void set_has_platform_or_app_classes(bool v) {

    _has_platform_or_app_classes = v;

  }

  bool has_platform_or_app_classes() { return _has_platform_or_app_classes; }

  jshort max_used_path_index()       { return _max_used_path_index; }

  jshort app_module_paths_start_index() { return _app_module_paths_start_index; }

  bool validate();

  int compute_crc();

  CDSFileMapRegion* space_at(int i) {

    assert(i >= 0 && i < NUM_CDS_REGIONS, "invalid region");

    return &_space[i];

  }

};

class FileMapInfo : public CHeapObj<mtInternal> {

private:

  friend class ManifestStream;

  friend class VMStructs;

  friend struct FileMapHeader;

  bool    _file_open;

  int     _fd;

  size_t  _file_offset;

private:

  static bool                  _validating_shared_path_table;

  // FileMapHeader describes the shared space data in the file to be

  // mapped.  This structure gets written to a file.  It is not a class, so

  // that the compilers don't add any compiler-private data to it.

public:

  struct FileMapHeaderBase : public CHeapObj<mtClass> {

    // Need to put something here. Otherwise, in product build, because CHeapObj has no virtual

    // methods, we would get sizeof(FileMapHeaderBase) == 1 with gcc.

    intx _dummy;

  };

  FileMapHeader * _header;

  const char* _full_path;

  char* _paths_misc_info;

  static FileMapInfo* _current_info;

  static bool _heap_pointers_need_patching;

  static void metaspace_pointers_do(MetaspaceClosure* it);

public:

  ~FileMapInfo();

  int    compute_header_crc()         { return _header->compute_crc(); }

  void   set_header_crc(int crc)      { _header->_crc = crc; }

  void   populate_header(size_t alignment);

  void   invalidate();

  int    version()                    { return _header->_version; }

  size_t alignment()                  { return _header->_alignment; }

  CompressedOops::Mode narrow_oop_mode() { return _header->_narrow_oop_mode; }

  address narrow_oop_base()    const  { return _header->_narrow_oop_base; }

  int     narrow_oop_shift()   const  { return _header->_narrow_oop_shift; }

  uintx   max_heap_size()      const  { return _header->_max_heap_size; }

  address narrow_klass_base()  const  { return _header->_narrow_klass_base; }

  int     narrow_klass_shift() const  { return _header->_narrow_klass_shift; }

  struct  FileMapHeader* header()     { return _header; }

  char*   misc_data_patching_start()          { return _header->_misc_data_patching_start; }

  void set_misc_data_patching_start(char* p)  { _header->_misc_data_patching_start = p; }

  char* read_only_tables_start()              { return _header->_read_only_tables_start; }

  void set_read_only_tables_start(char* p)    { _header->_read_only_tables_start = p; }

  address cds_i2i_entry_code_buffers() {

    return _header->_cds_i2i_entry_code_buffers;

  }

  void set_cds_i2i_entry_code_buffers(address addr) {

    _header->_cds_i2i_entry_code_buffers = addr;

  }

  size_t cds_i2i_entry_code_buffers_size() {

    return _header->_cds_i2i_entry_code_buffers_size;

  }

  void set_cds_i2i_entry_code_buffers_size(size_t s) {

    _header->_cds_i2i_entry_code_buffers_size = s;

  }

  void set_core_spaces_size(size_t s)    {  _header->_core_spaces_size = s; }

  size_t core_spaces_size()              { return _header->_core_spaces_size; }

  static FileMapInfo* current_info() {

    CDS_ONLY(return _current_info;)

    NOT_CDS(return NULL;)

  }

  static void assert_mark(bool check);

  // File manipulation.

  void  write_header();

  void  write_region(int region, char* base, size_t size,

                     bool read_only, bool allow_exec);

  size_t write_archive_heap_regions(GrowableArray<MemRegion> *heap_mem,

                                    GrowableArray<ArchiveHeapOopmapInfo> *oopmaps,

                                    int first_region_id, int max_num_regions,

                                    bool print_log);

  void  write_bytes(const void* buffer, size_t count);

  void  write_bytes_aligned(const void* buffer, size_t count);

  char* map_region(int i, char** top_ret);

  void  map_heap_regions_impl() NOT_CDS_JAVA_HEAP_RETURN;

  void  map_heap_regions() NOT_CDS_JAVA_HEAP_RETURN;

  void  fixup_mapped_heap_regions() NOT_CDS_JAVA_HEAP_RETURN;

  void  patch_archived_heap_embedded_pointers() NOT_CDS_JAVA_HEAP_RETURN;

  void  patch_archived_heap_embedded_pointers(MemRegion* ranges, int num_ranges,

                                              int first_region_idx) NOT_CDS_JAVA_HEAP_RETURN;

  bool  has_heap_regions()  NOT_CDS_JAVA_HEAP_RETURN_(false);

  MemRegion get_heap_regions_range_with_current_oop_encoding_mode() NOT_CDS_JAVA_HEAP_RETURN_(MemRegion());

  void  unmap_region(int i);

  bool  verify_region_checksum(int i);

  void  close();

  bool  is_open() { return _file_open; }

  ReservedSpace reserve_shared_memory();

  // JVM/TI RedefineClasses() support:

  // Remap the shared readonly space to shared readwrite, private.

  bool  remap_shared_readonly_as_readwrite();

  // Errors.

  static void fail_stop(const char *msg, ...) ATTRIBUTE_PRINTF(1, 2);

  static void fail_continue(const char *msg, ...) ATTRIBUTE_PRINTF(1, 2);

  bool is_in_shared_region(const void* p, int idx) NOT_CDS_RETURN_(false);

  // Stop CDS sharing and unmap CDS regions.

  static void stop_sharing_and_unmap(const char* msg);

  static void allocate_shared_path_table();

  static void check_nonempty_dir_in_shared_path_table();

  bool validate_shared_path_table();

  static void update_shared_classpath(ClassPathEntry *cpe, SharedClassPathEntry* ent, TRAPS);

#if INCLUDE_JVMTI

  static ClassFileStream* open_stream_for_jvmti(InstanceKlass* ik, Handle class_loader, TRAPS);

#endif

  static SharedClassPathEntry* shared_path(int index) {

  }

  static const char* shared_path_name(int index) {

    assert(index >= 0, "Sanity");

    return shared_path(index)->name();

  }

  static int get_number_of_shared_paths() {

  }

  char* region_addr(int idx);

 private:

  bool  map_heap_data(MemRegion **heap_mem, int first, int max, int* num,

                      bool is_open = false) NOT_CDS_JAVA_HEAP_RETURN_(false);

  void  dealloc_archive_heap_regions(MemRegion* regions, int num, bool is_open) NOT_CDS_JAVA_HEAP_RETURN;

  CDSFileMapRegion* space_at(int i) {

    return _header->space_at(i);

  }

  narrowOop offset_of_space(CDSFileMapRegion* spc) {

    return (narrowOop)(spc->_addr._offset);

  }

  // The starting address of spc, as calculated with CompressedOop::decode_non_null()

  address start_address_as_decoded_with_current_oop_encoding_mode(CDSFileMapRegion* spc) {

    return decode_start_address(spc, true);

  }

  // The starting address of spc, as calculated with HeapShared::decode_from_archive()

  address start_address_as_decoded_from_archive(CDSFileMapRegion* spc) {

    return decode_start_address(spc, false);

  }

  address decode_start_address(CDSFileMapRegion* spc, bool with_current_oop_encoding_mode);

#if INCLUDE_JVMTI

  static ClassPathEntry** _classpath_entries_for_jvmti;

  static ClassPathEntry* get_classpath_entry_for_jvmti(int i, TRAPS);

#endif

};

#endif // SHARE_MEMORY_FILEMAP_HPP