win32caml/history.c

   1 /***********************************************************************/
   2 /*                                                                     */
   3 /*                           Objective Caml                            */
   4 /*                                                                     */
   5 /*            Jacob Navia, after Xavier Leroy                          */
   6 /*                                                                     */
   7 /*  Copyright 2001 Institut National de Recherche en Informatique et   */
   8 /*  en Automatique.  All rights reserved.  This file is distributed    */
   9 /*  under the terms of the GNU Library General Public License, with    */
  10 /*  the special exception on linking described in file ../LICENSE.     */
  11 /*                                                                     */
  12 /***********************************************************************/
  13
  14 /***********************************************************************/
  15 /* Changes made by Chris Watford to enhance the source editor          */
  16 /* Began 14 Sept 2003 - watford@uiuc.edu                               */
  17 /***********************************************************************/
  18
  19 #include "inria.h"
  20 #include "history.h"
  21
  22 /*------------------------------------------------------------------------
  23 Procedure:     AddToHistory ID:2
  24 Author:            Chris Watford watford@uiuc.edu
  25 Purpose:       Adds an edit buffer to the history control
  26 Input:             Pointer to the edit buffer to add
  27 Output:
  28 Errors:
  29 --------------------------------------------------------------------------
  30 Edit History:
  31         15 Sept 2003 - Chris Watford watford@uiuc.edu
  32                 - Complete rewrite
  33                 - Got it to add the edit buffer to the history
  34         17 Sept 2003 - Chris Watford watford@uiuc.edu
  35                 - Added doubly link list support
  36 ------------------------------------------------------------------------*/
  37 void AddToHistory(EditBuffer *edBuf)
  38 {
  39         StatementHistory *newLine;
  40
  41         // sanity checks
  42         if(edBuf == NULL)
  43         {
  44                 return;
  45         } else if (edBuf->LineCount == 0 || edBuf->Lines == NULL) {
  46                 // fix any possible errors that may come from this
  47                 edBuf->LineCount = 0;
  48                 edBuf->Lines = NULL;
  49                 return;
  50         }
  51
  52         // setup newline and add as the front of the linked list
  53         newLine = SafeMalloc(sizeof(StatementHistory));
  54         newLine->Next = History;
  55         newLine->Prev = NULL;
  56         newLine->Statement = edBuf;
  57
  58         // setup back linking
  59         if(History != NULL)
  60                 History->Prev = newLine;
  61
  62         // set the history up
  63         History = newLine;
  64
  65         // search for the new history tail
  66         for(HistoryTail = (HistoryTail != NULL ? HistoryTail : History); HistoryTail->Next != NULL; HistoryTail = HistoryTail->Next);
  67 }
  68
  69 /*------------------------------------------------------------------------
  70 Procedure:     GetHistoryLine ID:2
  71 Author:            Chris Watford watford@uiuc.edu
  72 Purpose:       Returns an entry from the history table
  73 Input:             Index of the history entry to return
  74 Output:            The history entry as a single line
  75 Errors:
  76 --------------------------------------------------------------------------
  77 Edit History:
  78         15 Sept 2003 - Chris Watford watford@uiuc.edu
  79                 - Complete rewrite
  80         17 Sept 2003 - Chris Watford watford@uiuc.edu
  81                 - Added doubly link list support
  82 ------------------------------------------------------------------------*/
  83 char *GetHistoryLine(int n)
  84 {
  85         StatementHistory *histentry = History;
  86         int i;
  87
  88         // traverse linked list looking for member n
  89         for (i = 0; ((i < n) && (histentry != NULL)); i++, histentry = histentry->Next);
  90
  91         // figure out what to return
  92         if (histentry != NULL)
  93         {
  94                 return editbuffer_getasline(histentry->Statement);
  95         } else {
  96                 return "";
  97         }
  98 }