pith/hist.c

   1 /*
   2  * ========================================================================
   3  * Copyright 2013-2022 Eduardo Chappa
   4  * Copyright 2006-2007 University of Washington
   5  *
   6  * Licensed under the Apache License, Version 2.0 (the "License");
   7  * you may not use this file except in compliance with the License.
   8  * You may obtain a copy of the License at
   9  *
  10  *     http://www.apache.org/licenses/LICENSE-2.0
  11  *
  12  * ========================================================================
  13  */
  14
  15
  16 #include "../pith/headers.h"
  17 #include "../pith/conf.h"
  18 #include "../pith/hist.h"
  19
  20
  21 void
  22 init_hist(HISTORY_S **history, int histsize)
  23 {
  24     size_t l;
  25
  26     if(!history)
  27       return;
  28
  29     if(!*history){
  30         l = sizeof(**history) + histsize * sizeof(ONE_HIST_S);
  31         *history = (HISTORY_S *) fs_get(l);
  32         memset(*history, 0, l);
  33         (*history)->histsize = histsize;
  34         (*history)->origindex = histsize - 1;
  35         add_to_histlist(history);
  36     }
  37
  38     (*history)->curindex = (*history)->origindex;
  39 }
  40
  41
  42 void
  43 free_hist(HISTORY_S **history)
  44 {
  45     int i;
  46
  47     if(history && *history){
  48         for(i = 0; i < (*history)->histsize; i++)
  49           if((*history)->hist[i]){
  50             if((*history)->hist[i]->str)
  51                fs_give((void **) &(*history)->hist[i]->str);
  52             (*history)->hist[i]->cntxt = NULL;  /* taken care of elsewhere */
  53             fs_give((void **) &(*history)->hist[i]);
  54           }
  55
  56         fs_give((void **) history);
  57     }
  58 }
  59
  60 char *
  61 hist_in_pos(int pos, char **list, int llen, HISTORY_S *hist, int n)
  62 {
  63   if(pos < 0 || pos > llen + n)
  64     return NULL;
  65
  66   if(pos < llen)
  67      return list[pos];
  68
  69   hist->curindex = (hist->origindex + n - pos + llen) % hist->histsize;
  70   return((hist->hist[hist->curindex] && hist->hist[hist->curindex]->str)
  71            ? hist->hist[hist->curindex]->str : NULL);
  72 }
  73
  74 char *
  75 get_prev_hist(HISTORY_S *history, char *savethis, unsigned saveflags, void *cntxt)
  76 {
  77     int nextcurindex;
  78     size_t l;
  79
  80     if(!(history && history->histsize > 0))
  81       return NULL;
  82
  83     nextcurindex = (history->curindex + 1) % history->histsize;
  84
  85     /* already at start of history */
  86     if(nextcurindex == history->origindex
  87        || !(history->hist[nextcurindex] && history->hist[nextcurindex]->str
  88             && history->hist[nextcurindex]->str[0]))
  89       return NULL;
  90
  91     /* save what user typed */
  92     if(history->curindex == history->origindex){
  93         if(!savethis)
  94           savethis = "";
  95
  96         if(!history->hist[history->origindex]){
  97             history->hist[history->origindex] = (ONE_HIST_S *) fs_get(sizeof(ONE_HIST_S));
  98             memset(history->hist[history->origindex], 0, sizeof(ONE_HIST_S));
  99         }
 100
 101         if(history->hist[history->origindex]->str){
 102             if(strlen(history->hist[history->origindex]->str) < (l=strlen(savethis)))
 103               fs_resize((void **) &history->hist[history->origindex]->str, l+1);
 104
 105             strncpy(history->hist[history->origindex]->str, savethis, l+1);
 106             history->hist[history->origindex]->str[l] = '\0';
 107         }
 108         else
 109           history->hist[history->origindex]->str = cpystr(savethis);
 110
 111         history->hist[history->origindex]->flags = saveflags;
 112
 113         history->hist[history->origindex]->cntxt = cntxt;
 114     }
 115
 116     history->curindex = nextcurindex;
 117
 118     return((history->hist[history->curindex] && history->hist[history->curindex]->str)
 119            ? history->hist[history->curindex]->str : NULL);
 120 }
 121
 122
 123 char *
 124 get_next_hist(HISTORY_S *history, char *savethis, unsigned saveflags, void *cntxt)
 125 {
 126     if(!(history && history->histsize > 0))
 127       return NULL;
 128
 129     /* already at end (most recent) of history */
 130     if(history->curindex == history->origindex)
 131       return NULL;
 132
 133     history->curindex = (history->curindex + history->histsize - 1) % history->histsize;
 134
 135     return((history->hist[history->curindex] && history->hist[history->curindex]->str)
 136            ? history->hist[history->curindex]->str : NULL);
 137 }
 138
 139
 140 void
 141 save_hist(HISTORY_S *history, char *savethis, unsigned saveflags, void *cntxt)
 142 {
 143     size_t l;
 144     int plusone;
 145
 146     if(!(history && history->histsize > 0))
 147       return;
 148
 149     plusone = (history->origindex + 1) % history->histsize;
 150
 151     if(!history->hist[history->origindex]){
 152         history->hist[history->origindex] = (ONE_HIST_S *) fs_get(sizeof(ONE_HIST_S));
 153         memset(history->hist[history->origindex], 0, sizeof(ONE_HIST_S));
 154     }
 155
 156     if(savethis && savethis[0]
 157        && (!history->hist[history->origindex]->str
 158            || strcmp(history->hist[history->origindex]->str, savethis)
 159            || history->hist[history->origindex]->flags != saveflags
 160            || history->hist[history->origindex]->cntxt != cntxt)
 161        && !(history->hist[plusone] && history->hist[plusone]->str
 162             && !strcmp(history->hist[plusone]->str, savethis)
 163             && history->hist[history->origindex]->flags == saveflags
 164             && history->hist[history->origindex]->cntxt == cntxt)){
 165         if(history->hist[history->origindex]->str){
 166             if(strlen(history->hist[history->origindex]->str) < (l=strlen(savethis)))
 167               fs_resize((void **) &history->hist[history->origindex]->str, l+1);
 168
 169             strncpy(history->hist[history->origindex]->str, savethis, l+1);
 170             history->hist[history->origindex]->str[l] = '\0';
 171         }
 172         else{
 173             history->hist[history->origindex]->str = cpystr(savethis);
 174         }
 175
 176         history->hist[history->origindex]->flags = saveflags;
 177         history->hist[history->origindex]->cntxt = cntxt;
 178
 179         history->origindex = (history->origindex + history->histsize - 1) % history->histsize;
 180         if(history->hist[history->origindex] && history->hist[history->origindex]->str)
 181           history->hist[history->origindex]->str[0] = '\0';
 182     }
 183 }
 184
 185
 186 /*
 187  * Returns count of items entered into history.
 188  */
 189 int
 190 items_in_hist(HISTORY_S *history)
 191 {
 192     int i, cnt = 0;
 193
 194     if(history && history->histsize > 0)
 195       for(i = 0; i < history->histsize; i++)
 196         if(history->hist[i] && history->hist[i]->str)
 197           cnt++;
 198
 199     return(cnt);
 200 }
 201
 202
 203 static HISTORY_S **histlist[100];
 204
 205 void
 206 add_to_histlist(HISTORY_S **history)
 207 {
 208     int i;
 209
 210     if(history){
 211         /* find empty slot */
 212         for(i = 0; i < 100; i++)
 213           if(!histlist[i])
 214             break;
 215
 216         if(i < 100)
 217           histlist[i] = history;
 218     }
 219 }
 220
 221
 222 void
 223 free_histlist(void)
 224 {
 225     int i;
 226
 227     for(i = 0; i < 100; i++)
 228       if(histlist[i])
 229         free_hist(histlist[i]);
 230 }