4.3BSD - /usr/src/ucb/Mail/strings.c

   1: /*
   2:  * Copyright (c) 1980 Regents of the University of California.
   3:  * All rights reserved.  The Berkeley software License Agreement
   4:  * specifies the terms and conditions for redistribution.
   5:  */
   6: 
   7: #ifndef lint
   8: static char *sccsid = "@(#)strings.c	5.2 (Berkeley) 6/21/85";
   9: #endif not lint
  10: 
  11: /*
  12:  * Mail -- a mail program
  13:  *
  14:  * String allocation routines.
  15:  * Strings handed out here are reclaimed at the top of the command
  16:  * loop each time, so they need not be freed.
  17:  */
  18: 
  19: #include "rcv.h"
  20: 
  21: /*
  22:  * Allocate size more bytes of space and return the address of the
  23:  * first byte to the caller.  An even number of bytes are always
  24:  * allocated so that the space will always be on a word boundary.
  25:  * The string spaces are of exponentially increasing size, to satisfy
  26:  * the occasional user with enormous string size requests.
  27:  */
  28: 
  29: char *
  30: salloc(size)
  31: {
  32:     register char *t;
  33:     register int s;
  34:     register struct strings *sp;
  35:     int index;
  36: 
  37:     s = size;
  38:     s++;
  39:     s &= ~01;
  40:     index = 0;
  41:     for (sp = &stringdope[0]; sp < &stringdope[NSPACE]; sp++) {
  42:         if (sp->s_topFree == NOSTR && (STRINGSIZE << index) >= s)
  43:             break;
  44:         if (sp->s_nleft >= s)
  45:             break;
  46:         index++;
  47:     }
  48:     if (sp >= &stringdope[NSPACE])
  49:         panic("String too large");
  50:     if (sp->s_topFree == NOSTR) {
  51:         index = sp - &stringdope[0];
  52:         sp->s_topFree = (char *) calloc(STRINGSIZE << index,
  53:             (unsigned) 1);
  54:         if (sp->s_topFree == NOSTR) {
  55:             fprintf(stderr, "No room for space %d\n", index);
  56:             panic("Internal error");
  57:         }
  58:         sp->s_nextFree = sp->s_topFree;
  59:         sp->s_nleft = STRINGSIZE << index;
  60:     }
  61:     sp->s_nleft -= s;
  62:     t = sp->s_nextFree;
  63:     sp->s_nextFree += s;
  64:     return(t);
  65: }
  66: 
  67: /*
  68:  * Reset the string area to be empty.
  69:  * Called to free all strings allocated
  70:  * since last reset.
  71:  */
  72: 
  73: sreset()
  74: {
  75:     register struct strings *sp;
  76:     register int index;
  77: 
  78:     if (noreset)
  79:         return;
  80:     minit();
  81:     index = 0;
  82:     for (sp = &stringdope[0]; sp < &stringdope[NSPACE]; sp++) {
  83:         if (sp->s_topFree == NOSTR)
  84:             continue;
  85:         sp->s_nextFree = sp->s_topFree;
  86:         sp->s_nleft = STRINGSIZE << index;
  87:         index++;
  88:     }
  89: }

Defined functions

Defined variables