freebsd-dev/usr.bin/mail/strings.c
2010-12-19 16:25:23 +00:00

125 lines
3.5 KiB
C

/*
* Copyright (c) 1980, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#ifndef lint
#if 0
static char sccsid[] = "@(#)strings.c 8.1 (Berkeley) 6/6/93";
#endif
#endif /* not lint */
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/*
* Mail -- a mail program
*
* String allocation routines.
* Strings handed out here are reclaimed at the top of the command
* loop each time, so they need not be freed.
*/
#include "rcv.h"
#include "extern.h"
/*
* Allocate size more bytes of space and return the address of the
* first byte to the caller. An even number of bytes are always
* allocated so that the space will always be on a word boundary.
* The string spaces are of exponentially increasing size, to satisfy
* the occasional user with enormous string size requests.
*/
char *
salloc(int size)
{
char *t;
int s, index;
struct strings *sp;
s = size;
s += (sizeof(char *) - 1);
s &= ~(sizeof(char *) - 1);
index = 0;
for (sp = &stringdope[0]; sp < &stringdope[NSPACE]; sp++) {
if (sp->s_topFree == NULL && (STRINGSIZE << index) >= s)
break;
if (sp->s_nleft >= s)
break;
index++;
}
if (sp >= &stringdope[NSPACE])
errx(1, "String too large");
if (sp->s_topFree == NULL) {
index = sp - &stringdope[0];
if ((sp->s_topFree = malloc(STRINGSIZE << index)) == NULL)
err(1, "No room for space %d", index);
sp->s_nextFree = sp->s_topFree;
sp->s_nleft = STRINGSIZE << index;
}
sp->s_nleft -= s;
t = sp->s_nextFree;
sp->s_nextFree += s;
return (t);
}
/*
* Reset the string area to be empty.
* Called to free all strings allocated
* since last reset.
*/
void
sreset(void)
{
struct strings *sp;
int index;
if (noreset)
return;
index = 0;
for (sp = &stringdope[0]; sp < &stringdope[NSPACE]; sp++) {
if (sp->s_topFree == NULL)
continue;
sp->s_nextFree = sp->s_topFree;
sp->s_nleft = STRINGSIZE << index;
index++;
}
}
/*
* Make the string area permanent.
* Meant to be called in main, after initialization.
*/
void
spreserve(void)
{
struct strings *sp;
for (sp = &stringdope[0]; sp < &stringdope[NSPACE]; sp++)
sp->s_topFree = NULL;
}