2.11BSD#431 - /usr/src/ucb/Mail/strings.c

   1: /*
   2:  * Copyright (c) 1980 Regents of the University of California.
   3:  * 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: #if !defined(lint) && defined(DOSCCS)
  35: static char sccsid[] = "@(#)strings.c	5.9 (Berkeley) 6/1/90";
  36: #endif
  37: 
  38: /*
  39:  * Mail -- a mail program
  40:  *
  41:  * String allocation routines.
  42:  * Strings handed out here are reclaimed at the top of the command
  43:  * loop each time, so they need not be freed.
  44:  */
  45: 
  46: #include "rcv.h"
  47: 
  48: /*
  49:  * Allocate size more bytes of space and return the address of the
  50:  * first byte to the caller.  An even number of bytes are always
  51:  * allocated so that the space will always be on a word boundary.
  52:  * The string spaces are of exponentially increasing size, to satisfy
  53:  * the occasional user with enormous string size requests.
  54:  */
  55: 
  56: char *
  57: salloc(size)
  58: {
  59:     register char *t;
  60:     register int s;
  61:     register struct strings *sp;
  62:     int index;
  63: 
  64:     s = size;
  65:     s += 3;
  66:     s &= ~03;
  67:     index = 0;
  68:     for (sp = &stringdope[0]; sp < &stringdope[NSPACE]; sp++) {
  69:         if (sp->s_topFree == NOSTR && (STRINGSIZE << index) >= s)
  70:             break;
  71:         if (sp->s_nleft >= s)
  72:             break;
  73:         index++;
  74:     }
  75:     if (sp >= &stringdope[NSPACE])
  76:         panic("String too large");
  77:     if (sp->s_topFree == NOSTR) {
  78:         index = sp - &stringdope[0];
  79:         sp->s_topFree = malloc(STRINGSIZE << index);
  80:         if (sp->s_topFree == NOSTR) {
  81:             fprintf(stderr, "No room for space %d\n", index);
  82:             panic("Internal error");
  83:         }
  84:         sp->s_nextFree = sp->s_topFree;
  85:         sp->s_nleft = STRINGSIZE << index;
  86:     }
  87:     sp->s_nleft -= s;
  88:     t = sp->s_nextFree;
  89:     sp->s_nextFree += s;
  90:     return(t);
  91: }
  92: 
  93: /*
  94:  * Reset the string area to be empty.
  95:  * Called to free all strings allocated
  96:  * since last reset.
  97:  */
  98: sreset()
  99: {
 100:     register struct strings *sp;
 101:     register int index;
 102: 
 103:     if (noreset)
 104:         return;
 105:     index = 0;
 106:     for (sp = &stringdope[0]; sp < &stringdope[NSPACE]; sp++) {
 107:         if (sp->s_topFree == NOSTR)
 108:             continue;
 109:         sp->s_nextFree = sp->s_topFree;
 110:         sp->s_nleft = STRINGSIZE << index;
 111:         index++;
 112:     }
 113: }
 114: 
 115: /*
 116:  * Make the string area permanent.
 117:  * Meant to be called in main, after initialization.
 118:  */
 119: spreserve()
 120: {
 121:     register struct strings *sp;
 122: 
 123:     for (sp = &stringdope[0]; sp < &stringdope[NSPACE]; sp++)
 124:         sp->s_topFree = NOSTR;
 125: }

Defined functions

Defined variables