#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "memory/consspaceobject.h"
#include "memory/conspage.h"
#include "debug.h"
#include "memory/dump.h"
#include "memory/stack.h"
#include "memory/vectorspace.h"

Include dependency graph for conspage.c:

Functions
struct cons_pointer	allocate_cell (uint32_t tag)
	Allocates a cell with the specified `tag`.

void	dump_pages (URL_FILE *output)
	dump the allocated pages to this `output` stream.

void	free_cell (struct cons_pointer pointer)
	Frees the cell at the specified `pointer`; for all the types of cons-space object which point to other cons-space objects, cascade the decrement.

void	initialise_cons_pages ()
	initialise the cons page system; to be called exactly once during startup.

void	make_cons_page ()
	Make a cons page.

void	summarise_allocation ()

Variables
bool	conspageinitihasbeencalled = false
	Flag indicating whether conspage initialisation has been done.

struct cons_page *	conspages [NCONSPAGES]
	An array of pointers to cons pages.

struct cons_pointer	freelist = NIL
	The (global) pointer to the (global) freelist.

int	initialised_cons_pages = 0
	the number of cons pages which have thus far been initialised.

uint64_t	total_cells_allocated = 0
	keep track of total cells allocated and freed to check for leakage.

uint64_t	total_cells_freed = 0

Function Documentation

◆ allocate_cell()

struct cons_pointer allocate_cell ( uint32_t tag )

Allocates a cell with the specified tag.

Dangerous, primitive, low level.

Parameters

tag	the tag of the cell to allocate - must be a valid cons space tag.

Returns: the cons pointer which refers to the cell allocated.

Todo:: handle the case where another cons_page cannot be allocated; return an exception. Which, as we cannot create such an exception when cons space is exhausted, means we must construct it at init time.

Definition at line 222 of file conspage.c.

References allocate_cell(), cons_space_object::count, DEBUG_ALLOC, debug_printf(), freelist, FREETAG, make_cons_page(), NIL, cons_pointer::offset, cons_pointer::page, cons_space_object::payload, pointer2cell, cons_space_object::tag, TAGLENGTH, and total_cells_allocated.

Referenced by allocate_cell(), make_cons(), make_exception(), make_function(), make_integer(), make_lambda(), make_nlambda(), make_ratio(), make_read_stream(), make_real(), make_special(), make_string_like_thing(), make_time(), make_vec_pointer(), and make_write_stream().

◆ dump_pages()

void dump_pages ( URL_FILE * output )

dump the allocated pages to this output stream.

Definition at line 124 of file conspage.c.

References CONSPAGESIZE, dump_object(), initialised_cons_pages, and url_fwprintf.

Referenced by main().

◆ free_cell()

void free_cell ( struct cons_pointer pointer )

Frees the cell at the specified pointer; for all the types of cons-space object which point to other cons-space objects, cascade the decrement.

Dangerous, primitive, low level.

@pointer the cell to free

Definition at line 143 of file conspage.c.

References check_tag(), CONSTV, cons_space_object::count, DEBUG_ALLOC, debug_dump_object(), debug_printf(), dec_ref(), EXCEPTIONTV, free_vso(), freelist, FREETAG, FREETV, FUNCTIONTV, INTEGERTV, LAMBDATV, NIL, NLAMBDATV, cons_pointer::offset, cons_pointer::page, cons_space_object::payload, pointer2cell, RATIOTV, READTV, SPECIALTV, STRINGTV, SYMBOLTV, cons_space_object::tag, TAGLENGTH, total_cells_freed, url_fclose(), VECTORPOINTTV, and WRITETV.

Referenced by dec_ref().

◆ initialise_cons_pages()

void initialise_cons_pages ( )

initialise the cons page system; to be called exactly once during startup.

Definition at line 257 of file conspage.c.

References conspageinitihasbeencalled, conspages, DEBUG_ALLOC, debug_printf(), make_cons_page(), and NCONSPAGES.

Referenced by main().

◆ make_cons_page()

void make_cons_page ( )

Make a cons page.

Initialise all cells and prepend each to the freelist; if initialised_cons_pages is zero, do not prepend cells 0 and 1 to the freelist but initialise them as NIL and T respectively.

Todo:: we ought to handle cons space exhaustion more gracefully than just crashing; should probably return an exception instead, although obviously that exception would have to have been pre-built.

Definition at line 61 of file conspage.c.

References cons_page::cell, conspages, CONSPAGESIZE, cons_space_object::count, DEBUG_ALLOC, debug_printf(), freelist, FREETAG, initialised_cons_pages, MAXREFERENCE, NIL, NILTAG, cons_pointer::offset, cons_pointer::page, cons_space_object::payload, cons_space_object::tag, TAGLENGTH, and TRUETAG.