I manage memory using a simple scheme inspired by Hanson's idea of
arenas [#!hanson:90!#].
Basically, I allocate all the storage required when processing a
source file (primarily for names and scraps) using calls to
arena_getmem(n), where n specifies the number of bytes to
be allocated. When the storage is no longer required, the entire arena
is freed with a single call to arena_free(). Both operations
are quite fast.
@d Function p...
@extern void *arena_getmem();
extern void arena_free();
@
@o arena.c @typedef struct chunk struct chunk *next; char *limit; char *avail; Chunk; @| Chunk @
We define an empty chunk called first. The variable arena points
at the current chunk of memory; it's initially pointed at first.
As soon as some storage is required, a ``real'' chunk of memory will
be allocated and attached to first->next; storage will be
allocated from the new chunk (and later chunks if necessary).
@o arena.c
@static Chunk first = NULL, NULL, NULL ;
static Chunk *arena = &first;
@| first arena @