lib/array.c

   1 /*
   2 Operservice 2 - array.c
   3 Arrays are used all over in O2. This .c supplies some functions for handling
   4 them.
   5 (C) Michael Meier 2000-2001 - released under GPL
   6 -----------------------------------------------------------------------------
   7 This program is free software; you can redistribute it and/or
   8 modify it under the terms of the GNU General Public License
   9 as published by the Free Software Foundation; either version 2
  10 of the License, or (at your option) any later version.
  11
  12 This program is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with this program; if not, write to the Free Software
  19 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  20 ------------------------------------------------------------------------------
  21 */
  22
  23 #include <stdio.h>
  24 #include <stdlib.h>
  25 #include "array.h"
  26 #include "../core/error.h"
  27
  28 #ifndef ARLIM1
  29 #define ARLIM1 100     /* If new memory is needed for an array, this many */
  30                        /* records will be allocated. */
  31 #endif
  32 #ifndef ARLIM2
  33 #define ARLIM2 150     /* If more than this number of records are free in an */
  34                        /* array, memory is freed. */
  35 #endif
  36
  37 void array_init(array *a, unsigned int memberlen) {
  38   a->cursi=0;
  39   a->maxsi=0;
  40   a->memberlen=memberlen;
  41   a->content=NULL;
  42   a->arlim1=ARLIM1;
  43   a->arlim2=ARLIM2;
  44 }
  45
  46 void array_setlim1(array *a, unsigned int lim) {
  47   a->arlim1=lim;
  48 }
  49
  50 void array_setlim2(array *a, unsigned int lim) {
  51   a->arlim2=lim;
  52 }
  53
  54 int array_getfreeslot(array *a) {
  55   if ((a->cursi+1)>=a->maxsi) {
  56     /* Reallocation needed */
  57     a->maxsi+=a->arlim1;
  58     a->content=realloc(a->content,a->maxsi*a->memberlen);
  59     if (a->content==NULL) {
  60       Error("array",ERR_FATAL,"Couldn't allocate memory for growing array");
  61       exit(1);
  62     }
  63   }
  64   a->cursi++;
  65   return (a->cursi-1);
  66 }
  67
  68 void array_delslot(array *a, int slotn) {
  69   if (slotn >= a->cursi) { return; }
  70   a->cursi--;
  71   if (a->cursi!=slotn) {
  72     memcpy(a->content + (slotn * a->memberlen), a->content + (a->cursi * a->memberlen),a->memberlen);
  73   }
  74   if ((a->cursi + a->arlim2) < a->maxsi) {
  75     /* Let's free some memory */
  76     a->maxsi = a->cursi + a->arlim1;
  77     a->content=realloc(a->content,a->maxsi*a->memberlen);
  78     if (a->content==NULL) {
  79       Error("array",ERR_FATAL,"Couldn't allocate memory for shrinking array?!?");
  80       exit(1);
  81     }
  82   }
  83 }
  84
  85 void array_free(array *a) {
  86   free(a->content);
  87   a->cursi=0;
  88   a->maxsi=0;
  89   a->memberlen=0;
  90   a->content=NULL;
  91   a->arlim1=ARLIM1;
  92   a->arlim2=ARLIM2;
  93 }