jdk-24/src/hotspot/share/include/cds.h

/*
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
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 *
 * 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.
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#ifndef SHARE_INCLUDE_CDS_H
#define SHARE_INCLUDE_CDS_H

// This file declares the CDS data structures that are used by the HotSpot Serviceability Agent
// (see C sources inside src/jdk.hotspot.agent).
//
// We should use only standard C types. Do not use custom types such as bool, intx,
// etc, to avoid introducing unnecessary dependencies to other HotSpot type declarations.
//
// Also, this is a C header file. Do not use C++ here.

#define NUM_CDS_REGIONS 8 // this must be the same as MetaspaceShared::n_regions
#define CDS_ARCHIVE_MAGIC 0xf00baba2
#define CDS_DYNAMIC_ARCHIVE_MAGIC 0xf00baba8
#define CURRENT_CDS_ARCHIVE_VERSION 10
#define INVALID_CDS_ARCHIVE_VERSION -1

struct CDSFileMapRegion {
  int     _crc;               // CRC checksum of this region.
  int     _read_only;         // read only region?
  int     _allow_exec;        // executable code in this region?
  int     _is_heap_region;    // Used by SA and debug build.
  int     _is_bitmap_region;  // Relocation bitmap for RO/RW/MC/MD regions (used by SA and debug build).
  int     _mapped_from_file;  // Is this region mapped from a file?
                              // If false, this region was initialized using os::read().
  size_t  _file_offset;       // Data for this region starts at this offset in the archive file.
  size_t  _mapping_offset;    // This region should be mapped at this offset from the base address
                              // - for non-heap regions, the base address is SharedBaseAddress
                              // - for heap regions, the base address is the compressed oop encoding base
  size_t  _used;              // Number of bytes actually used by this region (excluding padding bytes added
                              // for alignment purposed.
  size_t  _oopmap_offset;     // Bitmap for relocating embedded oops (offset from SharedBaseAddress).
  size_t  _oopmap_size_in_bits;
  char*   _mapped_base;       // Actually mapped address (NULL if this region is not mapped).
};

struct CDSFileMapHeaderBase {
  unsigned int _magic;           // identify file type
  int          _crc;             // header crc checksum
  int          _version;         // must be CURRENT_CDS_ARCHIVE_VERSION
  struct CDSFileMapRegion _space[NUM_CDS_REGIONS];
};

typedef struct CDSFileMapHeaderBase CDSFileMapHeaderBase;

#endif // SHARE_INCLUDE_CDS_H