code.delx.au - refind/blob - refind/line_edit.c

   1 // Line-editing functions borrowed from gummiboot (cursor_left(),
   2 // cursor_right(), & line_edit()).
   3
   4 /*
   5  * Simple UEFI boot loader which executes configured EFI images, where the
   6  * default entry is selected by a configured pattern (glob) or an on-screen
   7  * menu.
   8  *
   9  * All gummiboot code is LGPL not GPL, to stay out of politics and to give
  10  * the freedom of copying code from programs to possible future libraries.
  11  *
  12  * This program is free software; you can redistribute it and/or modify it
  13  * under the terms of the GNU Lesser General Public License as published by
  14  * the Free Software Foundation; either version 2.1 of the License, or
  15  * (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful, but
  18  * WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  20  * Lesser General Public License for more details.
  21  *
  22  * Copyright (C) 2012-2013 Kay Sievers <kay@vrfy.org>
  23  * Copyright (C) 2012 Harald Hoyer <harald@redhat.com>
  24  *
  25  * "Any intelligent fool can make things bigger, more complex, and more violent.
  26 "
  27  *   -- Albert Einstein
  28  */
  29
  30 #include "global.h"
  31 #include "screen.h"
  32 #include "lib.h"
  33 #include "../include/refit_call_wrapper.h"
  34
  35 static void cursor_left(UINTN *cursor, UINTN *first)
  36 {
  37    if ((*cursor) > 0)
  38       (*cursor)--;
  39    else if ((*first) > 0)
  40       (*first)--;
  41 }
  42
  43 static void cursor_right(UINTN *cursor, UINTN *first, UINTN x_max, UINTN len)
  44 {
  45    if ((*cursor)+2 < x_max)
  46       (*cursor)++;
  47    else if ((*first) + (*cursor) < len)
  48       (*first)++;
  49 }
  50
  51 BOOLEAN line_edit(CHAR16 *line_in, CHAR16 **line_out, UINTN x_max) {
  52    CHAR16 *line;
  53    UINTN size;
  54    UINTN len;
  55    UINTN first;
  56    UINTN y_pos = 3;
  57    CHAR16 *print;
  58    UINTN cursor;
  59    BOOLEAN exit;
  60    BOOLEAN enter;
  61
  62    DrawScreenHeader(L"Line Editor");
  63    refit_call3_wrapper(ST->ConOut->SetCursorPosition, ST->ConOut, (ConWidth - 71) / 2, ConHeight - 1);
  64    refit_call2_wrapper(ST->ConOut->OutputString, ST->ConOut,
  65                        L"Use cursor keys to edit, Esc to exit, Enter to boot with edited options");
  66
  67    if (!line_in)
  68       line_in = L"";
  69    size = StrLen(line_in) + 1024;
  70    line = AllocatePool(size * sizeof(CHAR16));
  71    StrCpy(line, line_in);
  72    len = StrLen(line);
  73    print = AllocatePool(x_max * sizeof(CHAR16));
  74
  75    refit_call2_wrapper(ST->ConOut->EnableCursor, ST->ConOut, TRUE);
  76
  77    first = 0;
  78    cursor = 0;
  79    enter = FALSE;
  80    exit = FALSE;
  81    while (!exit) {
  82       UINTN index;
  83       EFI_STATUS err;
  84       EFI_INPUT_KEY key;
  85       UINTN i;
  86
  87       i = len - first;
  88       if (i >= x_max-2)
  89          i = x_max-2;
  90       CopyMem(print, line + first, i * sizeof(CHAR16));
  91       print[i++] = ' ';
  92       print[i] = '\0';
  93
  94       refit_call3_wrapper(ST->ConOut->SetCursorPosition, ST->ConOut, 0, y_pos);
  95       refit_call2_wrapper(ST->ConOut->OutputString, ST->ConOut, print);
  96       refit_call3_wrapper(ST->ConOut->SetCursorPosition, ST->ConOut, cursor, y_pos);
  97
  98       refit_call3_wrapper(BS->WaitForEvent, 1, &ST->ConIn->WaitForKey, &index);
  99       err = refit_call2_wrapper(ST->ConIn->ReadKeyStroke, ST->ConIn, &key);
 100       if (EFI_ERROR(err))
 101          continue;
 102
 103       switch (key.ScanCode) {
 104       case SCAN_ESC:
 105          exit = TRUE;
 106          break;
 107       case SCAN_HOME:
 108          cursor = 0;
 109          first = 0;
 110          continue;
 111       case SCAN_END:
 112          cursor = len;
 113          if (cursor >= x_max) {
 114             cursor = x_max-2;
 115             first = len - (x_max-2);
 116          }
 117          continue;
 118       case SCAN_UP:
 119          while((first + cursor) && line[first + cursor] == ' ')
 120             cursor_left(&cursor, &first);
 121          while((first + cursor) && line[first + cursor] != ' ')
 122             cursor_left(&cursor, &first);
 123          while((first + cursor) && line[first + cursor] == ' ')
 124             cursor_left(&cursor, &first);
 125          if (first + cursor != len && first + cursor)
 126             cursor_right(&cursor, &first, x_max, len);
 127          refit_call3_wrapper(ST->ConOut->SetCursorPosition, ST->ConOut, cursor, y_pos);
 128          continue;
 129       case SCAN_DOWN:
 130          while(line[first + cursor] && line[first + cursor] == ' ')
 131             cursor_right(&cursor, &first, x_max, len);
 132          while(line[first + cursor] && line[first + cursor] != ' ')
 133             cursor_right(&cursor, &first, x_max, len);
 134          while(line[first + cursor] && line[first + cursor] == ' ')
 135               cursor_right(&cursor, &first, x_max, len);
 136          refit_call3_wrapper(ST->ConOut->SetCursorPosition, ST->ConOut, cursor, y_pos);
 137          continue;
 138       case SCAN_RIGHT:
 139          if (first + cursor == len)
 140             continue;
 141          cursor_right(&cursor, &first, x_max, len);
 142          refit_call3_wrapper(ST->ConOut->SetCursorPosition, ST->ConOut, cursor, y_pos);
 143          continue;
 144       case SCAN_LEFT:
 145          cursor_left(&cursor, &first);
 146          refit_call3_wrapper(ST->ConOut->SetCursorPosition, ST->ConOut, cursor, y_pos);
 147          continue;
 148       case SCAN_DELETE:
 149          if (len == 0)
 150             continue;
 151          if (first + cursor == len)
 152             continue;
 153          for (i = first + cursor; i < len; i++)
 154             line[i] = line[i+1];
 155          line[len-1] = ' ';
 156          len--;
 157          continue;
 158       }
 159
 160       switch (key.UnicodeChar) {
 161       case CHAR_LINEFEED:
 162       case CHAR_CARRIAGE_RETURN:
 163          *line_out = line;
 164          line = NULL;
 165          enter = TRUE;
 166          exit = TRUE;
 167          break;
 168       case CHAR_BACKSPACE:
 169          if (len == 0)
 170             continue;
 171          if (first == 0 && cursor == 0)
 172             continue;
 173          for (i = first + cursor-1; i < len; i++)
 174             line[i] = line[i+1];
 175          len--;
 176          if (cursor > 0)
 177             cursor--;
 178          if (cursor > 0 || first == 0)
 179             continue;
 180          /* show full line if it fits */
 181          if (len < x_max-2) {
 182             cursor = first;
 183             first = 0;
 184             continue;
 185          }
 186          /* jump left to see what we delete */
 187          if (first > 10) {
 188             first -= 10;
 189             cursor = 10;
 190          } else {
 191             cursor = first;
 192             first = 0;
 193          }
 194          continue;
 195       case '\t':
 196       case ' ' ... '~':
 197       case 0x80 ... 0xffff:
 198          if (len+1 == size)
 199             continue;
 200          for (i = len; i > first + cursor; i--)
 201             line[i] = line[i-1];
 202          line[first + cursor] = key.UnicodeChar;
 203          len++;
 204          line[len] = '\0';
 205          if (cursor+2 < x_max)
 206             cursor++;
 207          else if (first + cursor < len)
 208             first++;
 209          continue;
 210       }
 211    }
 212
 213    refit_call2_wrapper(ST->ConOut->EnableCursor, ST->ConOut, FALSE);
 214    FreePool(print);
 215    FreePool(line);
 216    return enter;
 217 } /* BOOLEAN line_edit() */