/* $NetBSD: mvect.c,v 1.3 2020/03/18 19:05:21 christos Exp $ */
/*++
/* NAME
/* mvect 3
/* SUMMARY
/* memory vector management
/* SYNOPSIS
/* #include <mvect.h>
/*
/* char *mvect_alloc(vector, elsize, nelm, init_fn, wipe_fn)
/* MVECT *vector;
/* ssize_t elsize;
/* ssize_t nelm;
/* void (*init_fn)(char *ptr, ssize_t count);
/* void (*wipe_fn)(char *ptr, ssize_t count);
/*
/* char *mvect_realloc(vector, nelm)
/* MVECT *vector;
/* ssize_t nelm;
/*
/* char *mvect_free(vector)
/* MVECT *vector;
/* DESCRIPTION
/* This module supports memory management for arrays of arbitrary
/* objects. It is up to the application to provide specific code
/* that initializes and uses object memory.
/*
/* mvect_alloc() initializes memory for a vector with elements
/* of \fIelsize\fR bytes, and with at least \fInelm\fR elements.
/* \fIinit_fn\fR is a null pointer, or a pointer to a function
/* that initializes \fIcount\fR vector elements.
/* \fIwipe_fn\fR is a null pointer, or a pointer to a function
/* that is complementary to \fIinit_fn\fR. This routine is called
/* by mvect_free(). The result of mvect_alloc() is a pointer to
/* the allocated vector.
/*
/* mvect_realloc() guarantees that the specified vector has space
/* for at least \fInelm\fR elements. The result is a pointer to the
/* allocated vector, which may change across calls.
/*
/* mvect_free() releases storage for the named vector. The result
/* is a convenient null pointer.
/* SEE ALSO
/* mymalloc(3) memory management
/* DIAGNOSTICS
/* Problems are reported via the msg(3) diagnostics routines:
/* the requested amount of memory is not available; improper use
/* is detected; other fatal errors.
/* LICENSE
/* .ad
/* .fi
/* The Secure Mailer license must be distributed with this software.
/* AUTHOR(S)
/* Wietse Venema
/* IBM T.J. Watson Research
/* P.O. Box 704
/* Yorktown Heights, NY 10598, USA
/*
/* Wietse Venema
/* Google, Inc.
/* 111 8th Avenue
/* New York, NY 10011, USA
/*--*/
/* System library. */
#include <sys_defs.h>
/* Utility library. */
#include "mymalloc.h"
#include "mvect.h"
/* mvect_alloc - allocate memory vector */
char *mvect_alloc(MVECT *vect, ssize_t elsize, ssize_t nelm,
void (*init_fn) (char *, ssize_t), void (*wipe_fn) (char *, ssize_t))
{
vect->init_fn = init_fn;
vect->wipe_fn = wipe_fn;
vect->nelm = 0;
vect->ptr = mymalloc(elsize * nelm);
vect->nelm = nelm;
vect->elsize = elsize;
if (vect->init_fn)
vect->init_fn(vect->ptr, vect->nelm);
return (vect->ptr);
}
/* mvect_realloc - adjust memory vector allocation */
char *mvect_realloc(MVECT *vect, ssize_t nelm)
{
ssize_t old_len = vect->nelm;
ssize_t incr = nelm - old_len;
ssize_t new_nelm;
if (incr > 0) {
if (incr < old_len)
incr = old_len;
new_nelm = vect->nelm + incr;
vect->ptr = myrealloc(vect->ptr, vect->elsize * new_nelm);
vect->nelm = new_nelm;
if (vect->init_fn)
vect->init_fn(vect->ptr + old_len * vect->elsize, incr);
}
return (vect->ptr);
}
/* mvect_free - release memory vector storage */
char *mvect_free(MVECT *vect)
{
if (vect->wipe_fn)
vect->wipe_fn(vect->ptr, vect->nelm);
myfree(vect->ptr);
return (0);
}