1 /*

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

     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     4  *

     5  * This code is free software; you can redistribute it and/or modify it

     6  * under the terms of the GNU General Public License version 2 only, as

     7  * published by the Free Software Foundation.

     8  *

     9  * This code is distributed in the hope that it will be useful, but WITHOUT

    10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    12  * version 2 for more details (a copy is included in the LICENSE file that

    13  * accompanied this code).

    14  *

    15  * You should have received a copy of the GNU General Public License version

    16  * 2 along with this work; if not, write to the Free Software Foundation,

    17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    18  *

    19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

    20  * or visit www.oracle.com if you need additional information or have any

    21  * questions.

    22  *

    23  */

    24 

    25 #ifndef SHARE_INCLUDE_CDS_H

    26 #define SHARE_INCLUDE_CDS_H

    27 

    28 // This file declares the CDS data structures that are used by the HotSpot Serviceability Agent

    29 // (see C sources inside src/jdk.hotspot.agent).

    30 //

    31 // We should use only standard C types. Do not use custom types such as bool, intx,

    32 // etc, to avoid introducing unnecessary dependencies to other HotSpot type declarations.

    33 //

    34 // Also, this is a C header file. Do not use C++ here.

    35 

    36 #define NUM_CDS_REGIONS 9

    37 #define CDS_ARCHIVE_MAGIC 0xf00baba2

    38 #define CURRENT_CDS_ARCHIVE_VERSION 4

    39 #define INVALID_CDS_ARCHIVE_VERSION -1

    40 

    41 struct CDSFileMapRegion {

    42   int        _crc;           // crc checksum of the current space

    43   size_t     _file_offset;   // sizeof(this) rounded to vm page size

    44   union {

    45     char*    _base;          // copy-on-write base address

    46     size_t   _offset;        // offset from the compressed oop encoding base, only used

    47                              // by archive heap space

    48   } _addr;

    49   size_t     _used;          // for setting space top on read

    50   int        _read_only;     // read only space?

    51   int        _allow_exec;    // executable code in space?

    52 };

    53 

    54 struct CDSFileMapHeaderBase {

    55   unsigned int _magic;           // identify file type

    56   int          _crc;             // header crc checksum

    57   int          _version;         // must be CURRENT_CDS_ARCHIVE_VERSION

    58   struct CDSFileMapRegion _space[NUM_CDS_REGIONS];

    59 };

    60 

    61 typedef struct CDSFileMapHeaderBase CDSFileMapHeaderBase;

    62 

    63 #endif // SHARE_INCLUDE_CDS_H