/*-------------------------------------------------------------------------

 *

 * memutils_internal.h

 *    This file contains declarations for memory allocation utility

 *    functions for internal use.

 *

 *

 * Portions Copyright (c) 2022-2025, PostgreSQL Global Development Group

 * Portions Copyright (c) 1994, Regents of the University of California

 *

 * src/include/utils/memutils_internal.h

 *

 *-------------------------------------------------------------------------

 */

#ifndef MEMUTILS_INTERNAL_H

#define MEMUTILS_INTERNAL_H

#include "utils/memutils.h"

/* These functions implement the MemoryContext API for AllocSet context. */

extern void *AllocSetAlloc(MemoryContext context, Size size, int flags);

extern void AllocSetFree(void *pointer);

extern void *AllocSetRealloc(void *pointer, Size size, int flags);

extern void AllocSetReset(MemoryContext context);

extern void AllocSetDelete(MemoryContext context);

extern MemoryContext AllocSetGetChunkContext(void *pointer);

extern Size AllocSetGetChunkSpace(void *pointer);

extern bool AllocSetIsEmpty(MemoryContext context);

extern void AllocSetStats(MemoryContext context,

              MemoryStatsPrintFunc printfunc, void *passthru,

              MemoryContextCounters *totals,

              bool print_to_stderr);

#ifdef MEMORY_CONTEXT_CHECKING

extern void AllocSetCheck(MemoryContext context);

#endif

/* These functions implement the MemoryContext API for Generation context. */

extern void *GenerationAlloc(MemoryContext context, Size size, int flags);

extern void GenerationFree(void *pointer);

extern void *GenerationRealloc(void *pointer, Size size, int flags);

extern void GenerationReset(MemoryContext context);

extern void GenerationDelete(MemoryContext context);

extern MemoryContext GenerationGetChunkContext(void *pointer);

extern Size GenerationGetChunkSpace(void *pointer);

extern bool GenerationIsEmpty(MemoryContext context);

extern void GenerationStats(MemoryContext context,

              MemoryStatsPrintFunc printfunc, void *passthru,

              MemoryContextCounters *totals,

              bool print_to_stderr);

#ifdef MEMORY_CONTEXT_CHECKING

extern void GenerationCheck(MemoryContext context);

#endif

/* These functions implement the MemoryContext API for Slab context. */

extern void *SlabAlloc(MemoryContext context, Size size, int flags);

extern void SlabFree(void *pointer);

extern void *SlabRealloc(void *pointer, Size size, int flags);

extern void SlabReset(MemoryContext context);

extern void SlabDelete(MemoryContext context);

extern MemoryContext SlabGetChunkContext(void *pointer);

extern Size SlabGetChunkSpace(void *pointer);

extern bool SlabIsEmpty(MemoryContext context);

extern void SlabStats(MemoryContext context,

            MemoryStatsPrintFunc printfunc, void *passthru,

            MemoryContextCounters *totals,

            bool print_to_stderr);

#ifdef MEMORY_CONTEXT_CHECKING

extern void SlabCheck(MemoryContext context);

#endif

/*

 * These functions support the implementation of palloc_aligned() and are not

 * part of a fully-fledged MemoryContext type.

 */

extern void AlignedAllocFree(void *pointer);

extern void *AlignedAllocRealloc(void *pointer, Size size, int flags);

extern MemoryContext AlignedAllocGetChunkContext(void *pointer);

extern Size AlignedAllocGetChunkSpace(void *pointer);

 /* These functions implement the MemoryContext API for the Bump context. */

extern void *BumpAlloc(MemoryContext context, Size size, int flags);

extern void BumpFree(void *pointer);

extern void *BumpRealloc(void *pointer, Size size, int flags);

extern void BumpReset(MemoryContext context);

extern void BumpDelete(MemoryContext context);

extern MemoryContext BumpGetChunkContext(void *pointer);

extern Size BumpGetChunkSpace(void *pointer);

extern bool BumpIsEmpty(MemoryContext context);

extern void BumpStats(MemoryContext context, MemoryStatsPrintFunc printfunc,

            void *passthru, MemoryContextCounters *totals,

            bool print_to_stderr);

#ifdef MEMORY_CONTEXT_CHECKING

extern void BumpCheck(MemoryContext context);

#endif

/*

 * How many extra bytes do we need to request in order to ensure that we can

 * align a pointer to 'alignto'.  Since palloc'd pointers are already aligned

 * to MAXIMUM_ALIGNOF we can subtract that amount.  We also need to make sure

 * there is enough space for the redirection MemoryChunk.

 */

#define PallocAlignedExtraBytes(alignto) \

  ((alignto) + (sizeof(MemoryChunk) - MAXIMUM_ALIGNOF))

/*

 * MemoryContextMethodID

 *    A unique identifier for each MemoryContext implementation which

 *    indicates the index into the mcxt_methods[] array. See mcxt.c.

 *

 * For robust error detection, ensure that MemoryContextMethodID has a value

 * for each possible bit-pattern of MEMORY_CONTEXT_METHODID_MASK, and make

 * dummy entries for unused IDs in the mcxt_methods[] array.  We also try

 * to avoid using bit-patterns as valid IDs if they are likely to occur in

 * garbage data, or if they could falsely match on chunks that are really from

 * malloc not palloc.  (We can't tell that for most malloc implementations,

 * but it happens that glibc stores flag bits in the same place where we put

 * the MemoryContextMethodID, so the possible values are predictable for it.)

 */

typedef enum MemoryContextMethodID

{

  MCTX_0_RESERVED_UNUSEDMEM_ID, /* 0000 occurs in never-used memory */

  MCTX_1_RESERVED_GLIBC_ID, /* glibc malloc'd chunks usually match 0001 */

  MCTX_2_RESERVED_GLIBC_ID, /* glibc malloc'd chunks > 128kB match 0010 */

  MCTX_ASET_ID,

  MCTX_GENERATION_ID,

  MCTX_SLAB_ID,

  MCTX_ALIGNED_REDIRECT_ID,

  MCTX_BUMP_ID,

  MCTX_8_UNUSED_ID,

  MCTX_9_UNUSED_ID,

  MCTX_10_UNUSED_ID,

  MCTX_11_UNUSED_ID,

  MCTX_12_UNUSED_ID,

  MCTX_13_UNUSED_ID,

  MCTX_14_UNUSED_ID,

  MCTX_15_RESERVED_WIPEDMEM_ID  /* 1111 occurs in wipe_mem'd memory */

} MemoryContextMethodID;

/*

 * The number of bits that 8-byte memory chunk headers can use to encode the

 * MemoryContextMethodID.

 */

#define MEMORY_CONTEXT_METHODID_BITS 4

#define MEMORY_CONTEXT_METHODID_MASK \

  ((((uint64) 1) << MEMORY_CONTEXT_METHODID_BITS) - 1)

/*

 * This routine handles the context-type-independent part of memory

 * context creation.  It's intended to be called from context-type-

 * specific creation routines, and noplace else.

 */

extern void MemoryContextCreate(MemoryContext node,

                NodeTag tag,

                MemoryContextMethodID method_id,

                MemoryContext parent,

                const char *name);

extern void *MemoryContextAllocationFailure(MemoryContext context, Size size,

                      int flags);

pg_noreturn extern void MemoryContextSizeFailure(MemoryContext context, Size size,

                         int flags);

static inline void

MemoryContextCheckSize(MemoryContext context, Size size, int flags)

{

  if (unlikely(!AllocSizeIsValid(size)))

  {

    if (!(flags & MCXT_ALLOC_HUGE) || !AllocHugeSizeIsValid(size))

      MemoryContextSizeFailure(context, size, flags);

  }

}

Unexecuted instantiation: nodeAgg.c:MemoryContextCheckSize

Unexecuted instantiation: alignedalloc.c:MemoryContextCheckSize

aset.c:MemoryContextCheckSize

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{

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  if (unlikely(!AllocSizeIsValid(size)))

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  {

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    if (!(flags & MCXT_ALLOC_HUGE) || !AllocHugeSizeIsValid(size))

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      MemoryContextSizeFailure(context, size, flags);

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  }

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}

Unexecuted instantiation: bump.c:MemoryContextCheckSize

Unexecuted instantiation: generation.c:MemoryContextCheckSize

Unexecuted instantiation: mcxt.c:MemoryContextCheckSize

Unexecuted instantiation: slab.c:MemoryContextCheckSize

#endif              /* MEMUTILS_INTERNAL_H */