postgresql/src/include/nodes/memnodes.h
Neil Conway 849ec99753 Adjust the output of MemoryContextStats() so that the stats for a
child memory contexts is indented two spaces to the right of its
parent context.  This should make it easier to deduce the memory
context hierarchy from the output of MemoryContextStats().
2007-08-07 06:25:14 +00:00

78 lines
2.5 KiB
C

/*-------------------------------------------------------------------------
*
* memnodes.h
* POSTGRES memory context node definitions.
*
*
* Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/include/nodes/memnodes.h,v 1.33 2007/08/07 06:25:14 neilc Exp $
*
*-------------------------------------------------------------------------
*/
#ifndef MEMNODES_H
#define MEMNODES_H
#include "nodes/nodes.h"
/*
* MemoryContext
* A logical context in which memory allocations occur.
*
* MemoryContext itself is an abstract type that can have multiple
* implementations, though for now we have only AllocSetContext.
* The function pointers in MemoryContextMethods define one specific
* implementation of MemoryContext --- they are a virtual function table
* in C++ terms.
*
* Node types that are actual implementations of memory contexts must
* begin with the same fields as MemoryContext.
*
* Note: for largely historical reasons, typedef MemoryContext is a pointer
* to the context struct rather than the struct type itself.
*/
typedef struct MemoryContextMethods
{
void *(*alloc) (MemoryContext context, Size size);
/* call this free_p in case someone #define's free() */
void (*free_p) (MemoryContext context, void *pointer);
void *(*realloc) (MemoryContext context, void *pointer, Size size);
void (*init) (MemoryContext context);
void (*reset) (MemoryContext context);
void (*delete) (MemoryContext context);
Size (*get_chunk_space) (MemoryContext context, void *pointer);
bool (*is_empty) (MemoryContext context);
void (*stats) (MemoryContext context, int level);
#ifdef MEMORY_CONTEXT_CHECKING
void (*check) (MemoryContext context);
#endif
} MemoryContextMethods;
typedef struct MemoryContextData
{
NodeTag type; /* identifies exact kind of context */
MemoryContextMethods *methods; /* virtual function table */
MemoryContext parent; /* NULL if no parent (toplevel context) */
MemoryContext firstchild; /* head of linked list of children */
MemoryContext nextchild; /* next child of same parent */
char *name; /* context name (just for debugging) */
} MemoryContextData;
/* utils/palloc.h contains typedef struct MemoryContextData *MemoryContext */
/*
* MemoryContextIsValid
* True iff memory context is valid.
*
* Add new context types to the set accepted by this macro.
*/
#define MemoryContextIsValid(context) \
((context) != NULL && \
(IsA((context), AllocSetContext)))
#endif /* MEMNODES_H */