xref: /petsc/include/petscsystypes.h (revision 90dd7910ac8a3b96da340052822a6326b2f7f7cc)

/* Portions of this code are under:
   Copyright (c) 2022 Advanced Micro Devices, Inc. All rights reserved.
*/

#ifndef PETSCSYSTYPES_H
#define PETSCSYSTYPES_H

#include <petscconf.h>
#include <petscconf_poison.h>
#include <petscfix.h>
#include <stddef.h>

/* SUBMANSEC = Sys */

/*MC
    PetscErrorCode - datatype used for return error code from almost all PETSc functions

    Level: beginner

.seealso: `PetscCall()`, `SETERRQ()`
M*/
typedef int PetscErrorCode;

/*MC

    PetscClassId - A unique id used to identify each PETSc class.

    Notes:
    Use `PetscClassIdRegister()` to obtain a new value for a new class being created. Usually
         XXXInitializePackage() calls it for each class it defines.

    Developer Notes:
    Internal integer stored in the `_p_PetscObject` data structure.
         These are all computed by an offset from the lowest one, `PETSC_SMALLEST_CLASSID`.

    Level: developer

.seealso: `PetscClassIdRegister()`, `PetscLogEventRegister()`, `PetscHeaderCreate()`
M*/
typedef int PetscClassId;

/*MC
    PetscMPIInt - datatype used to represent 'int' parameters to MPI functions.

    Level: intermediate

    Notes:
    This is always a 32 bit integer, sometimes it is the same as `PetscInt`, but if PETSc was built with --with-64-bit-indices but
           standard C/Fortran integers are 32 bit then this is NOT the same as `PetscInt`; it remains 32 bit.

    `PetscMPIIntCast`(a,&b) checks if the given `PetscInt` a will fit in a `PetscMPIInt`, if not it
      generates a `PETSC_ERR_ARG_OUTOFRANGE` error.

.seealso: `PetscBLASInt`, `PetscInt`, `PetscMPIIntCast()`

M*/
typedef int PetscMPIInt;

/*MC
    PetscSizeT - datatype used to represent sizes in memory (like size_t)

    Level: intermediate

    Notes:
    This is equivalent to size_t, but defined for consistency with Fortran, which lacks a native equivalent of size_t.

.seealso: `PetscInt`, `PetscInt64`, `PetscCount`

M*/
typedef size_t PetscSizeT;

/*MC
    PetscCount - signed datatype used to represent counts

    Level: intermediate

    Notes:
    This is equivalent to ptrdiff_t, but defined for consistency with Fortran, which lacks a native equivalent of ptrdiff_t.

    Use `PetscCount_FMT` to format with `PetscPrintf()`, `printf()`, and related functions.

.seealso: `PetscInt`, `PetscInt64`, `PetscSizeT`

M*/
typedef ptrdiff_t PetscCount;
#define PetscCount_FMT "td"

/*MC
    PetscEnum - datatype used to pass enum types within PETSc functions.

    Level: intermediate

.seealso: `PetscOptionsGetEnum()`, `PetscOptionsEnum()`, `PetscBagRegisterEnum()`
M*/
typedef enum {
  ENUM_DUMMY
} PetscEnum;

typedef short PetscShort;
typedef char  PetscChar;
typedef float PetscFloat;

/*MC
  PetscInt - PETSc type that represents an integer, used primarily to
      represent size of arrays and indexing into arrays. Its size can be configured with the option --with-64-bit-indices to be either 32-bit (default) or 64-bit.

  Notes:
  For MPI calls that require datatypes, use `MPIU_INT` as the datatype for `PetscInt`. It will automatically work correctly regardless of the size of PetscInt.

  Level: beginner

.seealso: `PetscBLASInt`, `PetscMPIInt`, `PetscReal`, `PetscScalar`, `PetscComplex`, `PetscInt`, `MPIU_REAL`, `MPIU_SCALAR`, `MPIU_COMPLEX`, `MPIU_INT`
M*/

#if defined(PETSC_HAVE_STDINT_H)
  #include <stdint.h>
#endif
#if defined(PETSC_HAVE_INTTYPES_H)
  #if !defined(__STDC_FORMAT_MACROS)
    #define __STDC_FORMAT_MACROS /* required for using PRId64 from c++ */
  #endif
  #include <inttypes.h>
  #if !defined(PRId64)
    #define PRId64 "ld"
  #endif
#endif

#if defined(PETSC_HAVE_STDINT_H) && defined(PETSC_HAVE_INTTYPES_H) && defined(PETSC_HAVE_MPI_INT64_T) /* MPI_INT64_T is not guaranteed to be a macro */
typedef int64_t PetscInt64;
#elif (PETSC_SIZEOF_LONG_LONG == 8)
typedef long long PetscInt64;
#elif defined(PETSC_HAVE___INT64)
typedef __int64 PetscInt64;
#else
  #error "cannot determine PetscInt64 type"
#endif

#if defined(PETSC_USE_64BIT_INDICES)
typedef PetscInt64 PetscInt;
#else
typedef int       PetscInt;
#endif

#if defined(PETSC_HAVE_STDINT_H) && defined(PETSC_HAVE_INTTYPES_H) && defined(PETSC_HAVE_MPI_INT64_T) /* MPI_INT64_T is not guaranteed to be a macro */
  #define MPIU_INT64     MPI_INT64_T
  #define PetscInt64_FMT PRId64
#elif (PETSC_SIZEOF_LONG_LONG == 8)
  #define MPIU_INT64     MPI_LONG_LONG_INT
  #define PetscInt64_FMT "lld"
#elif defined(PETSC_HAVE___INT64)
  #define MPIU_INT64     MPI_INT64_T
  #define PetscInt64_FMT "ld"
#else
  #error "cannot determine PetscInt64 type"
#endif

/*MC
   PetscBLASInt - datatype used to represent 'int' parameters to BLAS/LAPACK functions.

   Notes:
    Usually this is the same as `PetscIn`t, but if PETSc was built with --with-64-bit-indices but
           standard C/Fortran integers are 32 bit then this may not be the same as `PetscInt`,
           except on some BLAS/LAPACK implementations that support 64 bit integers see the notes below.

    `PetscErrorCode` `PetscBLASIntCast`(a,&b) checks if the given `PetscInt` a will fit in a `PetscBLASInt`, if not it
      generates a `PETSC_ERR_ARG_OUTOFRANGE` error

   Installation Notes:
    ./configure automatically determines the size of the integers used by BLAS/LAPACK except when --with-batch is used
    in that situation one must know (by some other means) if the integers used by BLAS/LAPACK are 64 bit and if so pass the flag --known-64-bit-blas-indice

    MATLAB ships with BLAS and LAPACK that use 64 bit integers, for example if you run ./configure with, the option
     --with-blaslapack-lib=[/Applications/MATLAB_R2010b.app/bin/maci64/libmwblas.dylib,/Applications/MATLAB_R2010b.app/bin/maci64/libmwlapack.dylib]

    MKL ships with both 32 and 64 bit integer versions of the BLAS and LAPACK. If you pass the flag -with-64-bit-blas-indices PETSc will link
    against the 64 bit version, otherwise it use the 32 bit version

    OpenBLAS can be built to use 64 bit integers. The ./configure options --download-openblas -with-64-bit-blas-indices will build a 64 bit integer version

    External packages such as hypre, ML, SuperLU etc do not provide any support for passing 64 bit integers to BLAS/LAPACK so cannot
    be used with PETSc when PETSc links against 64 bit integer BLAS/LAPACK. ./configure will generate an error if you attempt to link PETSc against any of
    these external libraries while using 64 bit integer BLAS/LAPACK.

   Level: intermediate

.seealso: `PetscMPIInt`, `PetscInt`, `PetscBLASIntCast()`

M*/
#if defined(PETSC_HAVE_64BIT_BLAS_INDICES)
  #define PetscBLASInt_FMT PetscInt64_FMT
typedef PetscInt64 PetscBLASInt;
#else
  #define PetscBLASInt_FMT "d"
typedef int       PetscBLASInt;
#endif

/*MC
   PetscCuBLASInt - datatype used to represent 'int' parameters to cuBLAS/cuSOLVER functions.

   Notes:
    As of this writing PetscCuBLASInt is always the system `int`.

    `PetscErrorCode` `PetscCuBLASIntCast`(a,&b) checks if the given `PetscInt` a will fit in a `PetscCuBLASInt`, if not it
      generates a `PETSC_ERR_ARG_OUTOFRANGE` error

   Level: intermediate

.seealso: `PetscBLASInt`, `PetscMPIInt`, `PetscInt`, `PetscCuBLASIntCast()`

M*/
typedef int PetscCuBLASInt;

/*MC
   PetscHipBLASInt - datatype used to represent 'int' parameters to hipBLAS/hipSOLVER functions.

   Notes:
    As of this writing PetscHipBLASInt is always the system `int`.

    PetscErrorCode PetscHipBLASIntCast(a,&b) checks if the given PetscInt a will fit in a PetscHipBLASInt, if not it
      generates a PETSC_ERR_ARG_OUTOFRANGE error

   Level: intermediate

.seealso: PetscBLASInt, PetscMPIInt, PetscInt, PetscHipBLASIntCast()

M*/
typedef int PetscHipBLASInt;

/*E
    PetscBool  - Logical variable. Actually an enum in C and a logical in Fortran.

   Level: beginner

   Developer Note:
   Why have `PetscBool`, why not use bool in C? The problem is that K and R C, C99 and C++ all have different mechanisms for
      boolean values. It is not easy to have a simple macro that that will work properly in all circumstances with all three mechanisms.

.seealso: `PETSC_TRUE`, `PETSC_FALSE`, `PetscNot()`, `PetscBool3`
E*/
typedef enum {
  PETSC_FALSE,
  PETSC_TRUE
} PetscBool;

/*E
    PetscBool3  - Ternary logical variable. Actually an enum in C and a 4 byte integer in Fortran.

   Level: beginner

   Note:
   Should not be used with the if (flg) or if (!flg) syntax.

.seealso: `PETSC_TRUE`, `PETSC_FALSE`, `PetscNot()`, `PETSC_BOOL3_TRUE`, `PETSC_BOOL3_FALSE`, `PETSC_BOOL3_UNKNOWN`
E*/
typedef enum {
  PETSC_BOOL3_FALSE,
  PETSC_BOOL3_TRUE,
  PETSC_BOOL3_UNKNOWN = -1
} PetscBool3;

#define PetscBool3ToBool(a) ((a) == PETSC_BOOL3_TRUE ? PETSC_TRUE : PETSC_FALSE)
#define PetscBoolToBool3(a) ((a) == PETSC_TRUE ? PETSC_BOOL3_TRUE : PETSC_BOOL3_FALSE)

/*MC
   PetscReal - PETSc type that represents a real number version of `PetscScalar`

   Notes:
   For MPI calls that require datatypes, use `MPIU_REAL` as the datatype for `PetscReal` and `MPIU_SUM`, `MPIU_MAX`, etc. for operations.
          They will automatically work correctly regardless of the size of `PetscReal`.

          See `PetscScalar` for details on how to ./configure the size of `PetscReal`.

   Level: beginner

.seealso: `PetscScalar`, `PetscComplex`, `PetscInt`, `MPIU_REAL`, `MPIU_SCALAR`, `MPIU_COMPLEX`, `MPIU_INT`
M*/

#if defined(PETSC_USE_REAL_SINGLE)
typedef float PetscReal;
#elif defined(PETSC_USE_REAL_DOUBLE)
typedef double    PetscReal;
#elif defined(PETSC_USE_REAL___FLOAT128)
  #if defined(__cplusplus)
extern "C" {
  #endif
  #include <quadmath.h>
  #if defined(__cplusplus)
}
  #endif
typedef __float128 PetscReal;
#elif defined(PETSC_USE_REAL___FP16)
typedef __fp16 PetscReal;
#endif /* PETSC_USE_REAL_* */

/*MC
   PetscComplex - PETSc type that represents a complex number with precision matching that of `PetscReal`.

   Synopsis:
   #include <petscsys.h>
   PetscComplex number = 1. + 2.*PETSC_i;

   Notes:
   For MPI calls that require datatypes, use `MPIU_COMPLEX` as the datatype for `PetscComplex` and `MPIU_SUM` etc for operations.
          They will automatically work correctly regardless of the size of `PetscComplex`.

          See PetscScalar for details on how to ./configure the size of `PetscReal`

          Complex numbers are automatically available if PETSc was able to find a working complex implementation

    Petsc has a 'fix' for complex numbers to support expressions such as std::complex<PetscReal> + `PetscInt`, which are not supported by the standard
    C++ library, but are convenient for petsc users. If the C++ compiler is able to compile code in petsccxxcomplexfix.h (This is checked by
    configure), we include petsccxxcomplexfix.h to provide this convenience.

    If the fix causes conflicts, or one really does not want this fix for a particular C++ file, one can define `PETSC_SKIP_CXX_COMPLEX_FIX`
    at the beginning of the C++ file to skip the fix.

   Level: beginner

.seealso: `PetscReal`, `PetscScalar`, `PetscComplex`, `PetscInt`, `MPIU_REAL`, `MPIU_SCALAR`, `MPIU_COMPLEX`, `MPIU_INT`, `PETSC_i`
M*/
#if !defined(PETSC_SKIP_COMPLEX)
  #if defined(PETSC_CLANGUAGE_CXX)
    #if !defined(PETSC_USE_REAL___FP16) && !defined(PETSC_USE_REAL___FLOAT128)
      #if defined(__cplusplus) && defined(PETSC_HAVE_CXX_COMPLEX) /* enable complex for library code */
        #define PETSC_HAVE_COMPLEX 1
      #elif !defined(__cplusplus) && defined(PETSC_HAVE_C99_COMPLEX) && defined(PETSC_HAVE_CXX_COMPLEX) /* User code only - conditional on library code complex support */
        #define PETSC_HAVE_COMPLEX 1
      #endif
    #elif defined(PETSC_USE_REAL___FLOAT128) && defined(PETSC_HAVE_C99_COMPLEX)
      #define PETSC_HAVE_COMPLEX 1
    #endif
  #else /* !PETSC_CLANGUAGE_CXX */
    #if !defined(PETSC_USE_REAL___FP16)
      #if !defined(__cplusplus) && defined(PETSC_HAVE_C99_COMPLEX) /* enable complex for library code */
        #define PETSC_HAVE_COMPLEX 1
      #elif defined(__cplusplus) && defined(PETSC_HAVE_C99_COMPLEX) && defined(PETSC_HAVE_CXX_COMPLEX) /* User code only - conditional on library code complex support */
        #define PETSC_HAVE_COMPLEX 1
      #endif
    #endif
  #endif /* PETSC_CLANGUAGE_CXX */
#endif   /* !PETSC_SKIP_COMPLEX */

#if defined(PETSC_HAVE_COMPLEX)
  #if defined(__cplusplus) /* C++ complex support */
    /* Locate a C++ complex template library */
    #if defined(PETSC_DESIRE_KOKKOS_COMPLEX) /* Defined in petscvec_kokkos.hpp for *.kokkos.cxx files */
      #define petsccomplexlib Kokkos
      #include <Kokkos_Complex.hpp>
    #elif defined(__CUDACC__) || defined(__HIPCC__)
      #define petsccomplexlib thrust
      #include <thrust/complex.h>
    #elif defined(PETSC_USE_REAL___FLOAT128)
      #include <complex.h>
    #else
      #define petsccomplexlib std
      #include <complex>
    #endif

    /* Define PetscComplex based on the precision */
    #if defined(PETSC_USE_REAL_SINGLE)
typedef petsccomplexlib::complex<float> PetscComplex;
    #elif defined(PETSC_USE_REAL_DOUBLE)
typedef petsccomplexlib::complex<double> PetscComplex;
    #elif defined(PETSC_USE_REAL___FLOAT128)
typedef __complex128 PetscComplex;
    #endif

    /* Include a PETSc C++ complex 'fix'. Check PetscComplex manual page for details */
    #if defined(PETSC_HAVE_CXX_COMPLEX_FIX) && !defined(PETSC_SKIP_CXX_COMPLEX_FIX)
      #include <petsccxxcomplexfix.h>
    #endif
  #else /* c99 complex support */
    #include <complex.h>
    #if defined(PETSC_USE_REAL_SINGLE) || defined(PETSC_USE_REAL___FP16)
typedef float _Complex PetscComplex;
    #elif defined(PETSC_USE_REAL_DOUBLE)
typedef double _Complex PetscComplex;
    #elif defined(PETSC_USE_REAL___FLOAT128)
typedef __complex128 PetscComplex;
    #endif /* PETSC_USE_REAL_* */
  #endif   /* !__cplusplus */
#endif     /* PETSC_HAVE_COMPLEX */

/*MC
   PetscScalar - PETSc type that represents either a double precision real number, a double precision
       complex number, a single precision real number, a __float128 real or complex or a __fp16 real - if the code is configured
       with --with-scalar-type=real,complex --with-precision=single,double,__float128,__fp16

   Notes:
   For MPI calls that require datatypes, use `MPIU_SCALAR` as the datatype for `PetscScalar` and `MPIU_SUM`, etc for operations. They will automatically work correctly regardless of the size of `PetscScalar`.

   Level: beginner

.seealso: `PetscReal`, `PetscComplex`, `PetscInt`, `MPIU_REAL`, `MPIU_SCALAR`, `MPIU_COMPLEX`, `MPIU_INT`, `PetscRealPart()`, `PetscImaginaryPart()`
M*/

#if defined(PETSC_USE_COMPLEX) && defined(PETSC_HAVE_COMPLEX)
typedef PetscComplex PetscScalar;
#else  /* PETSC_USE_COMPLEX */
typedef PetscReal PetscScalar;
#endif /* PETSC_USE_COMPLEX */

/*E
    PetscCopyMode  - Determines how an array or `PetscObject` passed to certain functions is copied or retained by the aggregate `PetscObject`

   Level: beginner

   For the array input:
$   `PETSC_COPY_VALUES` - the array values are copied into new space, the user is free to reuse or delete the passed in array
$   `PETSC_OWN_POINTER` - the array values are NOT copied, the object takes ownership of the array and will free it later, the user cannot change or
$                       delete the array. The array MUST have been obtained with PetscMalloc(). Hence this mode cannot be used in Fortran.
$   `PETSC_USE_POINTER` - the array values are NOT copied, the object uses the array but does NOT take ownership of the array. The user cannot use
$                       the array but the user must delete the array after the object is destroyed.

   For the PetscObject input:
$   `PETSC_COPY_VALUES` - the input `PetscObject` is cloned into the aggregate `PetscObject`; the user is free to reuse/modify the input `PetscObject` without side effects.
$   `PETSC_OWN_POINTER` - the input `PetscObject` is referenced by pointer (with reference count), thus should not be modified by the user. (Modification may cause errors or unintended side-effects in this or a future version of PETSc.)
   For either case above, the input `PetscObject` should be destroyed by the user when no longer needed (the aggregate object increases its reference count).
$   `PETSC_USE_POINTER` - invalid for `PetscObject` inputs.

E*/
typedef enum {
  PETSC_COPY_VALUES,
  PETSC_OWN_POINTER,
  PETSC_USE_POINTER
} PetscCopyMode;

/*MC
    PETSC_FALSE - False value of `PetscBool`

    Level: beginner

    Note:
    Zero integer

.seealso: `PetscBool`, `PetscBool3`, `PETSC_TRUE`
M*/

/*MC
    PETSC_TRUE - True value of `PetscBool`

    Level: beginner

    Note:
    Nonzero integer

.seealso: `PetscBool`, `PetscBool3`, `PETSC_FALSE`
M*/

/*MC
    PetscLogDouble - Used for logging times

  Notes:
  Contains double precision numbers that are not used in the numerical computations, but rather in logging, timing etc.

  Level: developer

M*/
typedef double PetscLogDouble;

/*E
    PetscDataType - Used for handling different basic data types.

   Level: beginner

   Notes:
   Use of this should be avoided if one can directly use `MPI_Datatype` instead.

   `PETSC_INT` is the datatype for a `PetscInt`, regardless of whether it is 4 or 8 bytes.
   `PETSC_REAL`, `PETSC_COMPLEX` and `PETSC_SCALAR` are the datatypes for `PetscReal`, `PetscComplex` and `PetscScalar`, regardless of their sizes.

   Developer Notes:
   It would be nice if we could always just use MPI Datatypes, why can we not?

   If you change any values in `PetscDatatype` make sure you update their usage in
   share/petsc/matlab/PetscBagRead.m and share/petsc/matlab/@PetscOpenSocket/read/write.m

   TODO: Add PETSC_INT32 and remove use of improper PETSC_ENUM

.seealso: `PetscBinaryRead()`, `PetscBinaryWrite()`, `PetscDataTypeToMPIDataType()`,
          `PetscDataTypeGetSize()`

E*/
typedef enum {
  PETSC_DATATYPE_UNKNOWN = 0,
  PETSC_DOUBLE           = 1,
  PETSC_COMPLEX          = 2,
  PETSC_LONG             = 3,
  PETSC_SHORT            = 4,
  PETSC_FLOAT            = 5,
  PETSC_CHAR             = 6,
  PETSC_BIT_LOGICAL      = 7,
  PETSC_ENUM             = 8,
  PETSC_BOOL             = 9,
  PETSC___FLOAT128       = 10,
  PETSC_OBJECT           = 11,
  PETSC_FUNCTION         = 12,
  PETSC_STRING           = 13,
  PETSC___FP16           = 14,
  PETSC_STRUCT           = 15,
  PETSC_INT              = 16,
  PETSC_INT64            = 17,
  PETSC_COUNT            = 18
} PetscDataType;

#if defined(PETSC_USE_REAL_SINGLE)
  #define PETSC_REAL PETSC_FLOAT
#elif defined(PETSC_USE_REAL_DOUBLE)
  #define PETSC_REAL PETSC_DOUBLE
#elif defined(PETSC_USE_REAL___FLOAT128)
  #define PETSC_REAL PETSC___FLOAT128
#elif defined(PETSC_USE_REAL___FP16)
  #define PETSC_REAL PETSC___FP16
#else
  #define PETSC_REAL PETSC_DOUBLE
#endif

#if defined(PETSC_USE_COMPLEX)
  #define PETSC_SCALAR PETSC_COMPLEX
#else
  #define PETSC_SCALAR PETSC_REAL
#endif

#define PETSC_FORTRANADDR PETSC_LONG

/*S
    PetscToken - 'Token' used for managing tokenizing strings

  Level: intermediate

.seealso: `PetscTokenCreate()`, `PetscTokenFind()`, `PetscTokenDestroy()`
S*/
typedef struct _p_PetscToken *PetscToken;

/*S
     PetscObject - any PETSc object, `PetscViewer`, `Mat`, `Vec`, `KSP` etc

   Level: beginner

   Notes:
   This is the base class from which all PETSc objects are derived from.

   In certain situations one can cast an object, for example a `Vec`, to a `PetscObject` with (`PetscObject`)vec

.seealso: `PetscObjectDestroy()`, `PetscObjectView()`, `PetscObjectGetName()`, `PetscObjectSetName()`, `PetscObjectReference()`, `PetscObjectDereference()`
S*/
typedef struct _p_PetscObject *PetscObject;

/*MC
    PetscObjectId - unique integer Id for a `PetscObject`

    Level: developer

    Note:
    Unlike pointer values, object ids are never reused so one may save a `PetscObjectId` and compare it to one obtained later from a `PetscObject` to determine
    if the objects are the same. Never compare two object pointer values.

.seealso: `PetscObjectState`, `PetscObjectGetId()`
M*/
typedef PetscInt64 PetscObjectId;

/*MC
    PetscObjectState - integer state for a `PetscObject`

    Level: developer

    Notes:
    Object state is always-increasing and (for objects that track state) can be used to determine if an object has
    changed since the last time you interacted with it.  It is 64-bit so that it will not overflow for a very long time.

.seealso: `PetscObjectId`, `PetscObjectStateGet()`, `PetscObjectStateIncrease()`, `PetscObjectStateSet()`
M*/
typedef PetscInt64 PetscObjectState;

/*S
     PetscFunctionList - Linked list of functions, possibly stored in dynamic libraries, accessed
      by string name

   Level: advanced

.seealso: `PetscFunctionListAdd()`, `PetscFunctionListDestroy()`
S*/
typedef struct _n_PetscFunctionList *PetscFunctionList;

/*E
  PetscFileMode - Access mode for a file.

  Level: beginner

$  `FILE_MODE_UNDEFINED` - initial invalid value
$  `FILE_MODE_READ` - open a file at its beginning for reading
$  `FILE_MODE_WRITE` - open a file at its beginning for writing (will create if the file does not exist)
$  `FILE_MODE_APPEND` - open a file at end for writing
$  `FILE_MODE_UPDATE` - open a file for updating, meaning for reading and writing
$  `FILE_MODE_APPEND_UPDATE` - open a file for updating, meaning for reading and writing, at the end

.seealso: `PetscViewerFileSetMode()`
E*/
typedef enum {
  FILE_MODE_UNDEFINED = -1,
  FILE_MODE_READ      = 0,
  FILE_MODE_WRITE,
  FILE_MODE_APPEND,
  FILE_MODE_UPDATE,
  FILE_MODE_APPEND_UPDATE
} PetscFileMode;

typedef void *PetscDLHandle;
typedef enum {
  PETSC_DL_DECIDE = 0,
  PETSC_DL_NOW    = 1,
  PETSC_DL_LOCAL  = 2
} PetscDLMode;

/*S
     PetscObjectList - Linked list of PETSc objects, each accessible by string name

   Level: developer

   Note:
   Used by `PetscObjectCompose()` and `PetscObjectQuery()`

.seealso: `PetscObjectListAdd()`, `PetscObjectListDestroy()`, `PetscObjectListFind()`, `PetscObjectCompose()`, `PetscObjectQuery()`, `PetscFunctionList`
S*/
typedef struct _n_PetscObjectList *PetscObjectList;

/*S
     PetscDLLibrary - Linked list of dynamics libraries to search for functions

   Level: advanced

.seealso: `PetscDLLibraryOpen()`
S*/
typedef struct _n_PetscDLLibrary *PetscDLLibrary;

/*S
     PetscContainer - Simple PETSc object that contains a pointer to any required data

   Level: advanced

   Note:
   This is useful to attach arbitrary data to a `PetscObject` with `PetscObjectCompose()` and `PetscObjectQuery()`

.seealso: `PetscObject`, `PetscContainerCreate()`, `PetscObjectCompose()`, `PetscObjectQuery()`
S*/
typedef struct _p_PetscContainer *PetscContainer;

/*S
     PetscRandom - Abstract PETSc object that manages generating random numbers

   Level: intermediate

.seealso: `PetscRandomCreate()`, `PetscRandomGetValue()`, `PetscRandomType`
S*/
typedef struct _p_PetscRandom *PetscRandom;

/*
   In binary files variables are stored using the following lengths,
  regardless of how they are stored in memory on any one particular
  machine. Use these rather then sizeof() in computing sizes for
  PetscBinarySeek().
*/
#define PETSC_BINARY_INT_SIZE    (32 / 8)
#define PETSC_BINARY_FLOAT_SIZE  (32 / 8)
#define PETSC_BINARY_CHAR_SIZE   (8 / 8)
#define PETSC_BINARY_SHORT_SIZE  (16 / 8)
#define PETSC_BINARY_DOUBLE_SIZE (64 / 8)
#define PETSC_BINARY_SCALAR_SIZE sizeof(PetscScalar)

/*E
  PetscBinarySeekType - argument to `PetscBinarySeek()`

  Level: advanced

.seealso: `PetscBinarySeek()`, `PetscBinarySynchronizedSeek()`
E*/
typedef enum {
  PETSC_BINARY_SEEK_SET = 0,
  PETSC_BINARY_SEEK_CUR = 1,
  PETSC_BINARY_SEEK_END = 2
} PetscBinarySeekType;

/*E
    PetscBuildTwoSidedType - algorithm for setting up two-sided communication

$  `PETSC_BUILDTWOSIDED_ALLREDUCE` - classical algorithm using an MPI_Allreduce with
$      a buffer of length equal to the communicator size. Not memory-scalable due to
$      the large reduction size. Requires only MPI-1.
$  `PETSC_BUILDTWOSIDED_IBARRIER` - nonblocking algorithm based on MPI_Issend and MPI_Ibarrier.
$      Proved communication-optimal in Hoefler, Siebert, and Lumsdaine (2010). Requires MPI-3.
$  `PETSC_BUILDTWOSIDED_REDSCATTER` - similar to above, but use more optimized function
$      that only communicates the part of the reduction that is necessary.  Requires MPI-2.

   Level: developer

.seealso: `PetscCommBuildTwoSided()`, `PetscCommBuildTwoSidedSetType()`, `PetscCommBuildTwoSidedGetType()`
E*/
typedef enum {
  PETSC_BUILDTWOSIDED_NOTSET     = -1,
  PETSC_BUILDTWOSIDED_ALLREDUCE  = 0,
  PETSC_BUILDTWOSIDED_IBARRIER   = 1,
  PETSC_BUILDTWOSIDED_REDSCATTER = 2
  /* Updates here must be accompanied by updates in finclude/petscsys.h and the string array in mpits.c */
} PetscBuildTwoSidedType;

/* NOTE: If you change this, you must also change the values in src/vec/f90-mod/petscvec.h */
/*E
  InsertMode - Whether entries are inserted or added into vectors or matrices

  Level: beginner

.seealso: `VecSetValues()`, `MatSetValues()`, `VecSetValue()`, `VecSetValuesBlocked()`,
          `VecSetValuesLocal()`, `VecSetValuesBlockedLocal()`, `MatSetValuesBlocked()`,
          `MatSetValuesBlockedLocal()`, `MatSetValuesLocal()`, `VecScatterBegin()`, `VecScatterEnd()`
E*/
typedef enum {
  NOT_SET_VALUES,
  INSERT_VALUES,
  ADD_VALUES,
  MAX_VALUES,
  MIN_VALUES,
  INSERT_ALL_VALUES,
  ADD_ALL_VALUES,
  INSERT_BC_VALUES,
  ADD_BC_VALUES
} InsertMode;

/*MC
    INSERT_VALUES - Put a value into a vector or matrix, overwrites any previous value

    Level: beginner

.seealso: `InsertMode`, `VecSetValues()`, `MatSetValues()`, `VecSetValue()`, `VecSetValuesBlocked()`,
          `VecSetValuesLocal()`, `VecSetValuesBlockedLocal()`, `MatSetValuesBlocked()`, `ADD_VALUES`,
          `MatSetValuesBlockedLocal()`, `MatSetValuesLocal()`, `VecScatterBegin()`, `VecScatterEnd()`, `MAX_VALUES`

M*/

/*MC
    ADD_VALUES - Adds a value into a vector or matrix, if there previously was no value, just puts the
                value into that location

    Level: beginner

.seealso: `InsertMode`, `VecSetValues()`, `MatSetValues()`, `VecSetValue()`, `VecSetValuesBlocked()`,
          `VecSetValuesLocal()`, `VecSetValuesBlockedLocal()`, `MatSetValuesBlocked()`, `INSERT_VALUES`,
          `MatSetValuesBlockedLocal()`, `MatSetValuesLocal()`, `VecScatterBegin()`, `VecScatterEnd()`, `MAX_VALUES`

M*/

/*MC
    MAX_VALUES - Puts the maximum of the scattered/gathered value and the current value into each location

    Level: beginner

.seealso: `InsertMode`, `VecScatterBegin()`, `VecScatterEnd()`, `ADD_VALUES`, `INSERT_VALUES`

M*/

/*MC
    MIN_VALUES - Puts the minimal of the scattered/gathered value and the current value into each location

    Level: beginner

.seealso: `InsertMode`, `VecScatterBegin()`, `VecScatterEnd()`, `ADD_VALUES`, `INSERT_VALUES`

M*/

/*S
   PetscSubcomm - A decomposition of an MPI communicator into subcommunicators

   Notes:
   After a call to `PetscSubcommSetType()`, `PetscSubcommSetTypeGeneral()`, or `PetscSubcommSetFromOptions()` one may call
$     `PetscSubcommChild()` returns the associated subcommunicator on this process
$     `PetscSubcommContiguousParent()` returns a parent communitor but with all child of the same subcommunicator having contiguous rank

   Sample Usage:
.vb
       `PetscSubcommCreate()`
       `PetscSubcommSetNumber()`
       `PetscSubcommSetType`(`PETSC_SUBCOMM_INTERLACED`);
       ccomm = `PetscSubcommChild()`
       `PetscSubcommDestroy()`
.ve

   Level: advanced

   Notes:
$   `PETSC_SUBCOMM_GENERAL` - similar to `MPI_Comm_split()` each process sets the new communicator (color) they will belong to and the order within that communicator
$   `PETSC_SUBCOMM_CONTIGUOUS` - each new communicator contains a set of process with contiguous ranks in the original MPI communicator
$   `PETSC_SUBCOMM_INTERLACED` - each new communictor contains a set of processes equally far apart in rank from the others in that new communicator

   Example: Consider a communicator with six processes split into 3 subcommunicators.
$     `PETSC_SUBCOMM_CONTIGUOUS` - the first communicator contains rank 0,1  the second rank 2,3 and the third rank 4,5 in the original ordering of the original communicator
$     `PETSC_SUBCOMM_INTERLACED` - the first communicator contains rank 0,3, the second 1,4 and the third 2,5

   Developer Note:
   This is used in objects such as `PCREDUNDANT` to manage the subcommunicators on which the redundant computations
   are performed.

.seealso: `PetscSubcommCreate()`, `PetscSubcommSetNumber()`, `PetscSubcommSetType()`, `PetscSubcommView()`, `PetscSubcommSetFromOptions()`

S*/
typedef struct _n_PetscSubcomm *PetscSubcomm;
typedef enum {
  PETSC_SUBCOMM_GENERAL    = 0,
  PETSC_SUBCOMM_CONTIGUOUS = 1,
  PETSC_SUBCOMM_INTERLACED = 2
} PetscSubcommType;

/*S
     PetscHeap - A simple class for managing heaps

   Level: intermediate

.seealso: `PetscHeapCreate()`, `PetscHeapAdd()`, `PetscHeapPop()`, `PetscHeapPeek()`, `PetscHeapStash()`, `PetscHeapUnstash()`, `PetscHeapView()`, `PetscHeapDestroy()`
S*/
typedef struct _PetscHeap *PetscHeap;

typedef struct _n_PetscShmComm *PetscShmComm;
typedef struct _n_PetscOmpCtrl *PetscOmpCtrl;

/*S
   PetscSegBuffer - a segmented extendable buffer

   Level: developer

.seealso: `PetscSegBufferCreate()`, `PetscSegBufferGet()`, `PetscSegBufferExtract()`, `PetscSegBufferDestroy()`
S*/
typedef struct _n_PetscSegBuffer *PetscSegBuffer;

typedef struct _n_PetscOptionsHelpPrinted *PetscOptionsHelpPrinted;
#endif