reactos/apps/utils/cmd/history.c

   1 /*
   2  *  HISTORY.C - command line history.
   3  *
   4  *
   5  *  History:
   6  *
   7  *    14/01/95 (Tim Norman)
   8  *        started.
   9  *
  10  *    08/08/95 (Matt Rains)
  11  *        i have cleaned up the source code. changes now bring this source
  12  *        into guidelines for recommended programming practice.
  13  *
  14  *    27-Jul-1998 (John P Price <linux-guru@gcfl.net>)
  15  *        added config.h include
  16  *
  17  *    25-Jan-1999 (Eric Kohl <ekohl@abo.rhein-zeitung.de>)
  18  *        Cleanup!
  19  *        Unicode and redirection safe!
  20  */
  21
  22 #include "config.h"
  23
  24 #ifdef FEATURE_HISTORY
  25
  26 #include <windows.h>
  27 #include <tchar.h>
  28 #include <string.h>
  29 #include <stdlib.h>
  30
  31
  32 #define MAXLINES 128
  33
  34 static INT history_size = 2048;    /* make this configurable later */
  35
  36
  37 VOID History (INT dir, LPTSTR commandline)
  38 {
  39         static LPTSTR history = NULL;
  40         static LPTSTR lines[MAXLINES];
  41         static INT curline = 0;
  42         static INT numlines = 0;
  43         static INT maxpos = 0;
  44         INT count;
  45         INT length;
  46
  47         if (!history)
  48         {
  49                 history = malloc (history_size * sizeof (TCHAR));
  50                 lines[0] = history;
  51                 history[0] = 0;
  52         }
  53
  54         if (dir > 0)
  55         {
  56                 /* next command */
  57                 if (curline < numlines)
  58                 {
  59                         curline++;
  60                 }
  61
  62                 if (curline == numlines)
  63                 {
  64                         commandline[0] = 0;
  65                 }
  66                 else
  67                 {
  68                         _tcscpy (commandline, lines[curline]);
  69                 }
  70         }
  71         else if (dir < 0)
  72         {
  73                 /* prev command */
  74                 if (curline > 0)
  75                 {
  76                         curline--;
  77                 }
  78
  79                 _tcscpy (commandline, lines[curline]);
  80         }
  81         else
  82         {
  83                 /* add to history */
  84                 /* remove oldest string until there's enough room for next one */
  85                 /* strlen (commandline) must be less than history_size! */
  86                 while ((maxpos + (INT)_tcslen (commandline) + 1 > history_size) || (numlines >= MAXLINES))
  87                 {
  88                         length = _tcslen (lines[0]) + 1;
  89
  90                         for (count = 0; count < maxpos && count + (lines[1] - lines[0]) < history_size; count++)
  91                         {
  92                                 history[count] = history[count + length];
  93                         }
  94
  95                         maxpos -= length;
  96
  97                         for (count = 0; count <= numlines && count < MAXLINES; count++)
  98                         {
  99                                 lines[count] = lines[count + 1] - length;
 100                         }
 101
 102                         numlines--;
 103 #ifdef DEBUG
 104                         ConOutPrintf (_T("Reduced size:  %ld lines\n"), numlines);
 105
 106                         for (count = 0; count < numlines; count++)
 107                         {
 108                                 ConOutPrintf (_T("%d: %s\n"), count, lines[count]);
 109                         }
 110 #endif
 111                 }
 112
 113                 _tcscpy (lines[numlines], commandline);
 114                 numlines++;
 115                 lines[numlines] = lines[numlines - 1] + _tcslen (commandline) + 1;
 116                 maxpos += _tcslen (commandline) + 1;
 117                 /* last line, empty */
 118                 curline = numlines;
 119         }
 120
 121         return;
 122 }
 123
 124 #endif