mail_cmds/mail/strings.c

   1 /*
   2  * Copyright (c) 1980, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by the University of
  16  *      California, Berkeley and its contributors.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 #ifndef lint
  35 #if 0
  36 static char sccsid[] = "@(#)strings.c   8.1 (Berkeley) 6/6/93";
  37 #endif
  38 static const char rcsid[] =
  39   "$FreeBSD: src/usr.bin/mail/strings.c,v 1.5 2002/06/30 05:25:06 obrien Exp $";
  40 #endif /* not lint */
  41
  42 #include <sys/cdefs.h>
  43
  44 /*
  45  * Mail -- a mail program
  46  *
  47  * String allocation routines.
  48  * Strings handed out here are reclaimed at the top of the command
  49  * loop each time, so they need not be freed.
  50  */
  51
  52 #include "rcv.h"
  53 #include "extern.h"
  54
  55 /*
  56  * Allocate size more bytes of space and return the address of the
  57  * first byte to the caller.  An even number of bytes are always
  58  * allocated so that the space will always be on a word boundary.
  59  * The string spaces are of exponentially increasing size, to satisfy
  60  * the occasional user with enormous string size requests.
  61  */
  62
  63 char *
  64 salloc(size)
  65         int size;
  66 {
  67         char *t;
  68         int s, index;
  69         struct strings *sp;
  70
  71         s = size;
  72         s += (sizeof(char *) - 1);
  73         s &= ~(sizeof(char *) - 1);
  74         index = 0;
  75         for (sp = &stringdope[0]; sp < &stringdope[NSPACE]; sp++) {
  76                 if (sp->s_topFree == NULL && (STRINGSIZE << index) >= s)
  77                         break;
  78                 if (sp->s_nleft >= s)
  79                         break;
  80                 index++;
  81         }
  82         if (sp >= &stringdope[NSPACE])
  83                 errx(1, "String too large");
  84         if (sp->s_topFree == NULL) {
  85                 index = sp - &stringdope[0];
  86                 if ((sp->s_topFree = malloc(STRINGSIZE << index)) == NULL)
  87                         err(1, "No room for space %d", index);
  88                 sp->s_nextFree = sp->s_topFree;
  89                 sp->s_nleft = STRINGSIZE << index;
  90         }
  91         sp->s_nleft -= s;
  92         t = sp->s_nextFree;
  93         sp->s_nextFree += s;
  94         return (t);
  95 }
  96
  97 /*
  98  * Reset the string area to be empty.
  99  * Called to free all strings allocated
 100  * since last reset.
 101  */
 102 void
 103 sreset()
 104 {
 105         struct strings *sp;
 106         int index;
 107
 108         if (noreset)
 109                 return;
 110         index = 0;
 111         for (sp = &stringdope[0]; sp < &stringdope[NSPACE]; sp++) {
 112                 if (sp->s_topFree == NULL)
 113                         continue;
 114                 sp->s_nextFree = sp->s_topFree;
 115                 sp->s_nleft = STRINGSIZE << index;
 116                 index++;
 117         }
 118 }
 119
 120 /*
 121  * Make the string area permanent.
 122  * Meant to be called in main, after initialization.
 123  */
 124 void
 125 spreserve()
 126 {
 127         struct strings *sp;
 128
 129         for (sp = &stringdope[0]; sp < &stringdope[NSPACE]; sp++)
 130                 sp->s_topFree = NULL;
 131 }