base/applications/regedit/hexedit.c

   1 /*
   2  * Hex editor control
   3  *
   4  * Copyright (C) 2004 Thomas Weidenmueller <w3seek@reactos.com>
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
  19  */
  20
  21 #include <regedit.h>
  22 typedef struct
  23 {
  24   HWND hWndSelf;
  25   HWND hWndParent;
  26   HLOCAL hBuffer;
  27   DWORD style;
  28   DWORD MaxBuffer;
  29   INT ColumnsPerLine;
  30   INT nLines;
  31   INT nVisibleLinesComplete;
  32   INT nVisibleLines;
  33   INT Position;
  34   INT LineHeight;
  35   INT CharWidth;
  36   HFONT hFont;
  37   BOOL SbVisible;
  38
  39   INT LeftMargin;
  40   INT AddressSpacing;
  41   INT SplitSpacing;
  42
  43   BOOL EditingField;
  44   INT CaretCol;
  45   INT CaretLine;
  46 } HEXEDIT_DATA, *PHEXEDIT_DATA;
  47
  48 /* hit test codes */
  49 #define HEHT_LEFTMARGIN (0x1)
  50 #define HEHT_ADDRESS    (0x2)
  51 #define HEHT_ADDRESSSPACING     (0x3)
  52 #define HEHT_HEXDUMP    (0x4)
  53 #define HEHT_HEXDUMPSPACING     (0x5)
  54 #define HEHT_ASCIIDUMP  (0x6)
  55 #define HEHT_RIGHTMARGIN        (0x7)
  56
  57 INT_PTR CALLBACK HexEditWndProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam);
  58
  59 ATOM
  60 WINAPI
  61 RegisterHexEditorClass(HINSTANCE hInstance)
  62 {
  63   WNDCLASSEX WndClass;
  64
  65   ZeroMemory(&WndClass, sizeof(WNDCLASSEX));
  66   WndClass.cbSize = sizeof(WNDCLASSEX);
  67   WndClass.style = CS_DBLCLKS;
  68   WndClass.lpfnWndProc = (WNDPROC)HexEditWndProc;
  69   WndClass.cbWndExtra = sizeof(PHEXEDIT_DATA);
  70   WndClass.hInstance = hInstance;
  71   WndClass.hCursor = LoadCursor(0, IDC_IBEAM);
  72   WndClass.hbrBackground = (HBRUSH)(COLOR_WINDOW + 1);
  73   WndClass.lpszClassName = HEX_EDIT_CLASS_NAME;
  74
  75   return RegisterClassEx(&WndClass);
  76 }
  77
  78 BOOL
  79 WINAPI
  80 UnregisterHexEditorClass(HINSTANCE hInstance)
  81 {
  82   return UnregisterClass(HEX_EDIT_CLASS_NAME, hInstance);
  83 }
  84
  85 /*** Helper functions *********************************************************/
  86
  87 static VOID
  88 HEXEDIT_MoveCaret(PHEXEDIT_DATA hed, BOOL Scroll)
  89 {
  90   SCROLLINFO si;
  91
  92   si.cbSize = sizeof(SCROLLINFO);
  93   si.fMask = SIF_POS;
  94   GetScrollInfo(hed->hWndSelf, SB_VERT, &si);
  95
  96   if(Scroll)
  97   {
  98     if(si.nPos > hed->CaretLine)
  99     {
 100       si.nPos = hed->CaretLine;
 101       SetScrollInfo(hed->hWndSelf, SB_VERT, &si, TRUE);
 102       GetScrollInfo(hed->hWndSelf, SB_VERT, &si);
 103       InvalidateRect(hed->hWndSelf, NULL, TRUE);
 104     }
 105     else if(hed->CaretLine >= (hed->nVisibleLinesComplete + si.nPos))
 106     {
 107       si.nPos = hed->CaretLine - hed->nVisibleLinesComplete + 1;
 108       SetScrollInfo(hed->hWndSelf, SB_VERT, &si, TRUE);
 109       GetScrollInfo(hed->hWndSelf, SB_VERT, &si);
 110       InvalidateRect(hed->hWndSelf, NULL, TRUE);
 111     }
 112   }
 113
 114   if(hed->EditingField)
 115     SetCaretPos(hed->LeftMargin + ((4 + hed->AddressSpacing + (3 * hed->CaretCol)) * hed->CharWidth) - 1, (hed->CaretLine - si.nPos) * hed->LineHeight);
 116   else
 117     SetCaretPos(hed->LeftMargin + ((4 + hed->AddressSpacing + hed->SplitSpacing + (3 * hed->ColumnsPerLine) + hed->CaretCol) * hed->CharWidth) - 2, (hed->CaretLine - si.nPos) * hed->LineHeight);
 118 }
 119
 120 static VOID
 121 HEXEDIT_Update(PHEXEDIT_DATA hed)
 122 {
 123   SCROLLINFO si;
 124   RECT rcClient;
 125   BOOL SbVisible;
 126   INT bufsize, cvislines;
 127
 128   GetClientRect(hed->hWndSelf, &rcClient);
 129   hed->style = GetWindowLongPtr(hed->hWndSelf, GWL_STYLE);
 130
 131   bufsize = (hed->hBuffer ? (INT) LocalSize(hed->hBuffer) : 0);
 132   hed->nLines = max(bufsize / hed->ColumnsPerLine, 1);
 133   if(bufsize > hed->ColumnsPerLine && (bufsize % hed->ColumnsPerLine) > 0)
 134   {
 135     hed->nLines++;
 136   }
 137
 138   if(hed->LineHeight > 0)
 139   {
 140     hed->nVisibleLinesComplete = cvislines = rcClient.bottom / hed->LineHeight;
 141     hed->nVisibleLines = hed->nVisibleLinesComplete;
 142     if(rcClient.bottom % hed->LineHeight)
 143     {
 144       hed->nVisibleLines++;
 145     }
 146   }
 147   else
 148   {
 149     hed->nVisibleLines = cvislines = 0;
 150   }
 151
 152   SbVisible = bufsize > 0 && cvislines < hed->nLines;
 153   ShowScrollBar(hed->hWndSelf, SB_VERT, SbVisible);
 154
 155   /* update scrollbar */
 156   si.cbSize = sizeof(SCROLLINFO);
 157   si.fMask = SIF_RANGE | SIF_PAGE;
 158   si.nMin = 0;
 159   si.nMax = ((bufsize > 0) ? hed->nLines - 1 : 0);
 160   si.nPage = ((hed->LineHeight > 0) ? rcClient.bottom / hed->LineHeight : 0);
 161   SetScrollInfo(hed->hWndSelf, SB_VERT, &si, TRUE);
 162
 163   if(IsWindowVisible(hed->hWndSelf) && SbVisible != hed->SbVisible)
 164   {
 165     InvalidateRect(hed->hWndSelf, NULL, TRUE);
 166   }
 167
 168   hed->SbVisible = SbVisible;
 169 }
 170
 171 static HFONT
 172 HEXEDIT_GetFixedFont(VOID)
 173 {
 174   LOGFONT lf;
 175   GetObject(GetStockObject(ANSI_FIXED_FONT), sizeof(LOGFONT), &lf);
 176   return CreateFontIndirect(&lf);
 177 }
 178
 179 static VOID
 180 HEXEDIT_PaintLines(PHEXEDIT_DATA hed, HDC hDC, DWORD ScrollPos, DWORD First, DWORD Last, RECT *rc)
 181 {
 182   DWORD dx, dy, linestart;
 183   INT x;
 184   PBYTE buf, current, end, line;
 185   size_t bufsize;
 186   TCHAR hex[3], addr[17];
 187   RECT rct;
 188
 189   FillRect(hDC, rc, (HBRUSH)(COLOR_WINDOW + 1));
 190
 191   if(hed->hBuffer)
 192   {
 193     bufsize = LocalSize(hed->hBuffer);
 194     buf = LocalLock(hed->hBuffer);
 195   }
 196   else
 197   {
 198     buf = NULL;
 199     bufsize = 0;
 200
 201     if(ScrollPos + First == 0)
 202     {
 203       /* draw address */
 204       _stprintf(addr, _T("%04X"), 0);
 205       TextOut(hDC, hed->LeftMargin, First * hed->LineHeight, addr, 4);
 206     }
 207   }
 208
 209   if(buf)
 210   {
 211     end = buf + bufsize;
 212     dy = First * hed->LineHeight;
 213     linestart = (ScrollPos + First) * hed->ColumnsPerLine;
 214     current = buf + linestart;
 215     Last = min(hed->nLines - ScrollPos, Last);
 216
 217     while(First <= Last && current < end)
 218     {
 219       DWORD dh;
 220
 221       dx = hed->LeftMargin;
 222
 223       /* draw address */
 224       _stprintf(addr, _T("%04lX"), linestart);
 225       TextOut(hDC, dx, dy, addr, 4);
 226
 227       dx += ((4 + hed->AddressSpacing) * hed->CharWidth);
 228       dh = (3 * hed->CharWidth);
 229
 230       rct.left = dx;
 231       rct.top = dy;
 232       rct.right = rct.left + dh;
 233       rct.bottom = dy + hed->LineHeight;
 234
 235       /* draw hex map */
 236       dx += (hed->CharWidth / 2);
 237       line = current;
 238       for(x = 0; x < hed->ColumnsPerLine && current < end; x++)
 239       {
 240         rct.left += dh;
 241         rct.right += dh;
 242
 243         _stprintf(hex, _T("%02X"), *(current++));
 244         ExtTextOut(hDC, dx, dy, ETO_OPAQUE, &rct, hex, 2, NULL);
 245         dx += dh;
 246       }
 247
 248       /* draw ascii map */
 249       dx = ((4 + hed->AddressSpacing + hed->SplitSpacing + (hed->ColumnsPerLine * 3)) * hed->CharWidth);
 250       current = line;
 251       for(x = 0; x < hed->ColumnsPerLine && current < end; x++)
 252       {
 253         _stprintf(hex, _T("%C"), *(current++));
 254         hex[0] = ((hex[0] & _T('\x007f')) >= _T(' ') ? hex[0] : _T('.'));
 255         TextOut(hDC, dx, dy, hex, 1);
 256         dx += hed->CharWidth;
 257       }
 258
 259       dy += hed->LineHeight;
 260       linestart += hed->ColumnsPerLine;
 261       First++;
 262     }
 263   }
 264
 265   LocalUnlock(hed->hBuffer);
 266 }
 267
 268 static DWORD
 269 HEXEDIT_HitRegionTest(PHEXEDIT_DATA hed, POINTS pt)
 270 {
 271   int d;
 272
 273   if(pt.x <= hed->LeftMargin)
 274   {
 275     return HEHT_LEFTMARGIN;
 276   }
 277
 278   pt.x -= hed->LeftMargin;
 279   d = (4 * hed->CharWidth);
 280   if(pt.x <= d)
 281   {
 282     return HEHT_ADDRESS;
 283   }
 284
 285   pt.x -= d;
 286   d = (hed->AddressSpacing * hed->CharWidth);
 287   if(pt.x <= d)
 288   {
 289     return HEHT_ADDRESSSPACING;
 290   }
 291
 292   pt.x -= d;
 293   d = (3 * hed->ColumnsPerLine * hed->CharWidth);
 294   if(pt.x <= d)
 295   {
 296     return HEHT_HEXDUMP;
 297   }
 298
 299   pt.x -= d;
 300   d = (hed->SplitSpacing * hed->CharWidth);
 301   if(pt.x <= d)
 302   {
 303     return HEHT_HEXDUMPSPACING;
 304   }
 305
 306   pt.x -= d;
 307   d = (hed->ColumnsPerLine * hed->CharWidth);
 308   if(pt.x <= d)
 309   {
 310     return HEHT_ASCIIDUMP;
 311   }
 312
 313   return HEHT_RIGHTMARGIN;
 314 }
 315
 316 static DWORD
 317 HEXEDIT_PositionFromPoint(PHEXEDIT_DATA hed, POINTS pt, DWORD Hit, POINT *EditPos, BOOL *EditField)
 318 {
 319   SCROLLINFO si;
 320   DWORD Pos, bufsize;
 321
 322   si.cbSize = sizeof(SCROLLINFO);
 323   si.fMask = SIF_POS;
 324   GetScrollInfo(hed->hWndSelf, SB_VERT, &si);
 325
 326   EditPos->x = 0;
 327
 328   if(hed->LineHeight > 0)
 329   {
 330     EditPos->y = min(si.nPos + (pt.y / hed->LineHeight), hed->nLines - 1);
 331   }
 332   else
 333   {
 334     EditPos->y = si.nPos;
 335   }
 336
 337   switch(Hit)
 338   {
 339     case HEHT_LEFTMARGIN:
 340     case HEHT_ADDRESS:
 341     case HEHT_ADDRESSSPACING:
 342     case HEHT_HEXDUMP:
 343       pt.x -= (SHORT) hed->LeftMargin + ((4 + hed->AddressSpacing) * hed->CharWidth);
 344       *EditField = TRUE;
 345       break;
 346
 347     default:
 348       pt.x -= hed->LeftMargin + ((4 + hed->AddressSpacing + hed->SplitSpacing + (3 * hed->ColumnsPerLine)) * hed->CharWidth);
 349       *EditField = FALSE;
 350       break;
 351   }
 352
 353   if(pt.x > 0)
 354   {
 355     INT BlockWidth = (*EditField ? hed->CharWidth * 3 : hed->CharWidth);
 356     EditPos->x = min(hed->ColumnsPerLine, pt.x / BlockWidth);
 357   }
 358
 359   bufsize = (hed->hBuffer ? (DWORD) LocalSize(hed->hBuffer) : 0);
 360   Pos = (EditPos->y * hed->ColumnsPerLine) + EditPos->x;
 361   if(Pos > bufsize)
 362   {
 363     INT tmp = bufsize % hed->ColumnsPerLine;
 364     Pos = bufsize;
 365     EditPos->x = (tmp == 0 ? hed->ColumnsPerLine : tmp);
 366   }
 367   return Pos;
 368 }
 369
 370 /*** Control specific messages ************************************************/
 371
 372 static LRESULT
 373 HEXEDIT_HEM_LOADBUFFER(PHEXEDIT_DATA hed, PVOID Buffer, DWORD Size)
 374 {
 375   if(Buffer != NULL && Size > 0)
 376   {
 377     LPVOID buf;
 378
 379     if(hed->MaxBuffer > 0 && Size > hed->MaxBuffer)
 380     {
 381       Size = hed->MaxBuffer;
 382     }
 383
 384     if(hed->hBuffer)
 385     {
 386       if(Size > 0)
 387       {
 388         if(LocalSize(hed->hBuffer) != Size)
 389         {
 390           hed->hBuffer = LocalReAlloc(hed->hBuffer, Size, LMEM_MOVEABLE | LMEM_ZEROINIT);
 391         }
 392       }
 393       else
 394       {
 395         hed->hBuffer = LocalFree(hed->hBuffer);
 396         hed->Position = 0;
 397         HEXEDIT_Update(hed);
 398
 399         return 0;
 400       }
 401     }
 402     else if(Size > 0)
 403     {
 404       hed->hBuffer = LocalAlloc(LHND, Size);
 405     }
 406
 407     if(Size > 0)
 408     {
 409       buf = LocalLock(hed->hBuffer);
 410       if(buf)
 411       {
 412         memcpy(buf, Buffer, Size);
 413       }
 414       else
 415         Size = 0;
 416       LocalUnlock(hed->hBuffer);
 417     }
 418
 419     hed->Position = 0;
 420     HEXEDIT_Update(hed);
 421     return Size;
 422   }
 423   else if(hed->hBuffer)
 424   {
 425     hed->Position = 0;
 426     hed->hBuffer = LocalFree(hed->hBuffer);
 427     HEXEDIT_Update(hed);
 428   }
 429
 430   return 0;
 431 }
 432
 433 static LRESULT
 434 HEXEDIT_HEM_COPYBUFFER(PHEXEDIT_DATA hed, PVOID Buffer, DWORD Size)
 435 {
 436   size_t nCpy;
 437
 438   if(!hed->hBuffer)
 439   {
 440     return 0;
 441   }
 442
 443   if(Buffer != NULL && Size > 0)
 444   {
 445     nCpy = min(Size, LocalSize(hed->hBuffer));
 446     if(nCpy > 0)
 447     {
 448       PVOID buf;
 449
 450       buf = LocalLock(hed->hBuffer);
 451       if(buf)
 452       {
 453         memcpy(Buffer, buf, nCpy);
 454       }
 455       else
 456         nCpy = 0;
 457       LocalUnlock(hed->hBuffer);
 458     }
 459     return nCpy;
 460   }
 461
 462   return (LRESULT)LocalSize(hed->hBuffer);
 463 }
 464
 465 static LRESULT
 466 HEXEDIT_HEM_SETMAXBUFFERSIZE(PHEXEDIT_DATA hed, DWORD nMaxSize)
 467 {
 468   hed->MaxBuffer = nMaxSize;
 469   if(hed->MaxBuffer > 0 && hed->hBuffer && LocalSize(hed->hBuffer) > hed->MaxBuffer)
 470   {
 471     /* truncate the buffer */
 472     hed->hBuffer = LocalReAlloc(hed->hBuffer, hed->MaxBuffer, LMEM_MOVEABLE);
 473     HEXEDIT_Update(hed);
 474   }
 475   return 0;
 476 }
 477
 478 /*** Message Proc *************************************************************/
 479
 480 static LRESULT
 481 HEXEDIT_WM_NCCREATE(HWND hWnd, CREATESTRUCT *cs)
 482 {
 483   PHEXEDIT_DATA hed;
 484
 485   if(!(hed = HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, sizeof(HEXEDIT_DATA))))
 486   {
 487     return FALSE;
 488   }
 489
 490   hed->hWndSelf = hWnd;
 491   hed->hWndParent = cs->hwndParent;
 492   hed->style = cs->style;
 493
 494   hed->ColumnsPerLine = 8;
 495   hed->LeftMargin = 2;
 496   hed->AddressSpacing = 2;
 497   hed->SplitSpacing = 2;
 498   hed->EditingField = TRUE; /* in hexdump field */
 499
 500   SetWindowLongPtr(hWnd, 0, (DWORD_PTR)hed);
 501   HEXEDIT_Update(hed);
 502
 503   return TRUE;
 504 }
 505
 506 static LRESULT
 507 HEXEDIT_WM_NCDESTROY(PHEXEDIT_DATA hed)
 508 {
 509   if(hed->hBuffer)
 510   {
 511     //while(LocalUnlock(hed->hBuffer));
 512     LocalFree(hed->hBuffer);
 513   }
 514
 515   if(hed->hFont)
 516   {
 517     DeleteObject(hed->hFont);
 518   }
 519
 520   SetWindowLongPtr(hed->hWndSelf, 0, (DWORD_PTR)0);
 521   HeapFree(GetProcessHeap(), 0, hed);
 522
 523   return 0;
 524 }
 525
 526 static LRESULT
 527 HEXEDIT_WM_CREATE(PHEXEDIT_DATA hed)
 528 {
 529   UNREFERENCED_PARAMETER(hed);
 530   return 1;
 531 }
 532
 533 static LRESULT
 534 HEXEDIT_WM_SETFOCUS(PHEXEDIT_DATA hed)
 535 {
 536   CreateCaret(hed->hWndSelf, 0, 1, hed->LineHeight);
 537   HEXEDIT_MoveCaret(hed, FALSE);
 538   ShowCaret(hed->hWndSelf);
 539   return 0;
 540 }
 541
 542 static LRESULT
 543 HEXEDIT_WM_KILLFOCUS(PHEXEDIT_DATA hed)
 544 {
 545   UNREFERENCED_PARAMETER(hed);
 546   DestroyCaret();
 547   return 0;
 548 }
 549
 550 static LRESULT
 551 HEXEDIT_WM_VSCROLL(PHEXEDIT_DATA hed, WORD ThumbPosition, WORD SbCmd)
 552 {
 553   int ScrollY;
 554   SCROLLINFO si;
 555
 556   UNREFERENCED_PARAMETER(ThumbPosition);
 557
 558   ZeroMemory(&si, sizeof(SCROLLINFO));
 559   si.cbSize = sizeof(SCROLLINFO);
 560   si.fMask = SIF_ALL;
 561   GetScrollInfo(hed->hWndSelf, SB_VERT, &si);
 562
 563   ScrollY = si.nPos;
 564   switch(SbCmd)
 565   {
 566     case SB_TOP:
 567       si.nPos = si.nMin;
 568       break;
 569
 570     case SB_BOTTOM:
 571       si.nPos = si.nMax;
 572       break;
 573
 574     case SB_LINEUP:
 575       si.nPos--;
 576       break;
 577
 578     case SB_LINEDOWN:
 579       si.nPos++;
 580       break;
 581
 582     case SB_PAGEUP:
 583       si.nPos -= si.nPage;
 584       break;
 585
 586     case SB_PAGEDOWN:
 587       si.nPos += si.nPage;
 588       break;
 589
 590     case SB_THUMBTRACK:
 591       si.nPos = si.nTrackPos;
 592       break;
 593   }
 594
 595   si.fMask = SIF_POS;
 596   SetScrollInfo(hed->hWndSelf, SB_VERT, &si, TRUE);
 597   GetScrollInfo(hed->hWndSelf, SB_VERT, &si);
 598
 599   if(si.nPos != ScrollY)
 600   {
 601     ScrollWindow(hed->hWndSelf, 0, (ScrollY - si.nPos) * hed->LineHeight, NULL, NULL);
 602     UpdateWindow(hed->hWndSelf);
 603   }
 604
 605   return 0;
 606 }
 607
 608 static LRESULT
 609 HEXEDIT_WM_SETFONT(PHEXEDIT_DATA hed, HFONT hFont, BOOL bRedraw)
 610 {
 611   HDC hDC;
 612   TEXTMETRIC tm;
 613   HFONT hOldFont = 0;
 614
 615   if(hFont == 0)
 616   {
 617     hFont = HEXEDIT_GetFixedFont();
 618   }
 619
 620   hed->hFont = hFont;
 621   hDC = GetDC(hed->hWndSelf);
 622   if(hFont)
 623   {
 624     hOldFont = SelectObject(hDC, hFont);
 625   }
 626   GetTextMetrics(hDC, &tm);
 627   hed->LineHeight = tm.tmHeight;
 628   hed->CharWidth = tm.tmAveCharWidth;
 629   if(hOldFont)
 630   {
 631     SelectObject(hDC, hOldFont);
 632   }
 633   ReleaseDC(hed->hWndSelf, hDC);
 634
 635   if(bRedraw)
 636   {
 637     InvalidateRect(hed->hWndSelf, NULL, TRUE);
 638   }
 639
 640   return 0;
 641 }
 642
 643 static LRESULT
 644 HEXEDIT_WM_GETFONT(PHEXEDIT_DATA hed)
 645 {
 646   return (LRESULT)hed->hFont;
 647 }
 648
 649 static LRESULT
 650 HEXEDIT_WM_PAINT(PHEXEDIT_DATA hed)
 651 {
 652   PAINTSTRUCT ps;
 653   SCROLLINFO si;
 654   RECT rc;
 655   HBITMAP hbmp, hbmpold;
 656   INT nLines, nFirst;
 657   HFONT hOldFont;
 658   HDC hTempDC;
 659   DWORD height;
 660
 661   if(GetUpdateRect(hed->hWndSelf, &rc, FALSE) && (hed->LineHeight > 0))
 662   {
 663     ZeroMemory(&si, sizeof(SCROLLINFO));
 664     si.cbSize = sizeof(SCROLLINFO);
 665     si.fMask = SIF_POS;
 666     GetScrollInfo(hed->hWndSelf, SB_VERT, &si);
 667
 668     height = (rc.bottom - rc.top);
 669     nLines = height / hed->LineHeight;
 670     if((height % hed->LineHeight) > 0)
 671     {
 672       nLines++;
 673     }
 674     if(nLines > hed->nLines - si.nPos)
 675     {
 676       nLines = hed->nLines - si.nPos;
 677     }
 678     nFirst = rc.top / hed->LineHeight;
 679
 680     BeginPaint(hed->hWndSelf, &ps);
 681     if(!(hTempDC = CreateCompatibleDC(ps.hdc)))
 682     {
 683       FillRect(ps.hdc, &rc, (HBRUSH)(COLOR_WINDOW + 1));
 684       goto epaint;
 685     }
 686     if(!(hbmp = CreateCompatibleBitmap(hTempDC, ps.rcPaint.right, ps.rcPaint.bottom)))
 687     {
 688       FillRect(ps.hdc, &rc, (HBRUSH)(COLOR_WINDOW + 1));
 689       DeleteDC(hTempDC);
 690       goto epaint;
 691     }
 692     hbmpold = SelectObject(hTempDC, hbmp);
 693     hOldFont = SelectObject(hTempDC, hed->hFont);
 694     HEXEDIT_PaintLines(hed, hTempDC, si.nPos, nFirst, nFirst + nLines, &ps.rcPaint);
 695     BitBlt(ps.hdc, rc.left, rc.top, rc.right - rc.left, rc.bottom - rc.top, hTempDC, rc.left, rc.top, SRCCOPY);
 696     SelectObject(hTempDC, hOldFont);
 697     SelectObject(hTempDC, hbmpold);
 698
 699     DeleteObject(hbmp);
 700     DeleteDC(hTempDC);
 701
 702     epaint:
 703     EndPaint(hed->hWndSelf, &ps);
 704   }
 705
 706   return 0;
 707 }
 708
 709 static LRESULT
 710 HEXEDIT_WM_MOUSEWHEEL(PHEXEDIT_DATA hed, int cyMoveLines, WORD ButtonsDown, LPPOINTS MousePos)
 711 {
 712   SCROLLINFO si;
 713   int ScrollY;
 714
 715   UNREFERENCED_PARAMETER(ButtonsDown);
 716   UNREFERENCED_PARAMETER(MousePos);
 717
 718   SetFocus(hed->hWndSelf);
 719
 720   si.cbSize = sizeof(SCROLLINFO);
 721   si.fMask = SIF_ALL;
 722   GetScrollInfo(hed->hWndSelf, SB_VERT, &si);
 723
 724   ScrollY = si.nPos;
 725
 726   si.fMask = SIF_POS;
 727   si.nPos += cyMoveLines;
 728   SetScrollInfo(hed->hWndSelf, SB_VERT, &si, TRUE);
 729
 730   GetScrollInfo(hed->hWndSelf, SB_VERT, &si);
 731   if(si.nPos != ScrollY)
 732   {
 733     ScrollWindow(hed->hWndSelf, 0, (ScrollY - si.nPos) * hed->LineHeight, NULL, NULL);
 734     UpdateWindow(hed->hWndSelf);
 735   }
 736
 737   return 0;
 738 }
 739
 740 static LRESULT
 741 HEXEDIT_WM_GETDLGCODE(LPMSG Msg)
 742 {
 743   UNREFERENCED_PARAMETER(Msg);
 744   return DLGC_WANTARROWS | DLGC_WANTCHARS;
 745 }
 746
 747 static LRESULT
 748 HEXEDIT_WM_LBUTTONDOWN(PHEXEDIT_DATA hed, INT Buttons, POINTS Pt)
 749 {
 750   BOOL NewField;
 751   POINT EditPos;
 752   DWORD Hit = HEXEDIT_HitRegionTest(hed, Pt);
 753
 754   UNREFERENCED_PARAMETER(Buttons);
 755   SetFocus(hed->hWndSelf);
 756
 757   hed->Position = HEXEDIT_PositionFromPoint(hed, Pt, Hit, &EditPos, &NewField);
 758   hed->EditingField = NewField;
 759   hed->CaretCol = EditPos.x;
 760   hed->CaretLine = EditPos.y;
 761
 762   HEXEDIT_MoveCaret(hed, TRUE);
 763
 764   return 0;
 765 }
 766
 767 static BOOL
 768 HEXEDIT_WM_KEYDOWN(PHEXEDIT_DATA hed, INT VkCode)
 769 {
 770   size_t bufsize;
 771   BOOL shift, control;
 772
 773   if(GetKeyState(VK_MENU) & 0x8000)
 774   {
 775     return FALSE;
 776   }
 777
 778   shift = GetKeyState(VK_SHIFT) & 0x8000;
 779   control = GetKeyState(VK_CONTROL) & 0x8000;
 780
 781   bufsize = (hed->hBuffer ? LocalSize(hed->hBuffer) : 0);
 782
 783   switch(VkCode)
 784   {
 785     case VK_LEFT:
 786       if(hed->Position > 0)
 787       {
 788         if(--hed->CaretCol < 0)
 789         {
 790           hed->CaretLine--;
 791           hed->CaretCol = hed->ColumnsPerLine;
 792         }
 793         else
 794           hed->Position--;
 795       }
 796       HEXEDIT_MoveCaret(hed, TRUE);
 797       break;
 798
 799     case VK_RIGHT:
 800       if(hed->Position < (INT)bufsize)
 801       {
 802         if(++hed->CaretCol > hed->ColumnsPerLine)
 803         {
 804           hed->CaretCol = 0;
 805           hed->CaretLine++;
 806         }
 807         else
 808           hed->Position++;
 809       }
 810       HEXEDIT_MoveCaret(hed, TRUE);
 811       break;
 812
 813     case VK_UP:
 814       if(hed->Position > 0)
 815       {
 816         if(hed->CaretLine <= 0)
 817         {
 818           hed->CaretCol = 0;
 819           hed->Position = 0;
 820         }
 821         else
 822         {
 823           hed->CaretLine--;
 824           hed->Position -= hed->ColumnsPerLine;
 825         }
 826       }
 827       HEXEDIT_MoveCaret(hed, TRUE);
 828       break;
 829
 830     case VK_DOWN:
 831       if(hed->Position <= (INT)bufsize)
 832       {
 833         if(hed->CaretLine < hed->nLines - 1)
 834         {
 835           hed->Position += hed->ColumnsPerLine;
 836           hed->CaretLine++;
 837           if(hed->Position > (INT)bufsize)
 838           {
 839             hed->Position = (INT) bufsize;
 840             hed->CaretLine = (hed->nLines > 0 ? hed->nLines - 1 : 0);
 841             hed->CaretCol = (INT) bufsize % hed->ColumnsPerLine;
 842           }
 843         }
 844         else
 845         {
 846           INT tmp = (INT) bufsize % hed->ColumnsPerLine;
 847           hed->Position = (INT) bufsize;
 848           hed->CaretCol = (tmp == 0 ? hed->ColumnsPerLine : tmp);
 849         }
 850       }
 851       HEXEDIT_MoveCaret(hed, TRUE);
 852       break;
 853   }
 854
 855   return FALSE;
 856 }
 857
 858 static LRESULT
 859 HEXEDIT_WM_SIZE(PHEXEDIT_DATA hed, DWORD sType, WORD NewWidth, WORD NewHeight)
 860 {
 861   UNREFERENCED_PARAMETER(sType);
 862   UNREFERENCED_PARAMETER(NewHeight);
 863   UNREFERENCED_PARAMETER(NewWidth);
 864   HEXEDIT_Update(hed);
 865   return 0;
 866 }
 867
 868 INT_PTR CALLBACK
 869 HexEditWndProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
 870 {
 871   PHEXEDIT_DATA hed;
 872   POINTS p;
 873
 874   hed = (PHEXEDIT_DATA)(LONG_PTR)GetWindowLongPtr(hWnd, (DWORD_PTR)0);
 875   switch(uMsg)
 876   {
 877     case WM_ERASEBKGND:
 878       return TRUE;
 879
 880     case WM_PAINT:
 881       return HEXEDIT_WM_PAINT(hed);
 882
 883     case WM_KEYDOWN:
 884       return HEXEDIT_WM_KEYDOWN(hed, (INT)wParam);
 885
 886     case WM_VSCROLL:
 887       return HEXEDIT_WM_VSCROLL(hed, HIWORD(wParam), LOWORD(wParam));
 888
 889     case WM_SIZE:
 890       return HEXEDIT_WM_SIZE(hed, (DWORD)wParam, LOWORD(lParam), HIWORD(lParam));
 891
 892     case WM_LBUTTONDOWN:
 893     {
 894       p.x = LOWORD(lParam);
 895       p.y = HIWORD(lParam);
 896       return HEXEDIT_WM_LBUTTONDOWN(hed, (INT)wParam, p);
 897     }
 898
 899     case WM_MOUSEWHEEL:
 900     {
 901       UINT nScrollLines = 3;
 902       int delta = 0;
 903
 904       SystemParametersInfoW(SPI_GETWHEELSCROLLLINES, 0, &nScrollLines, 0);
 905       delta -= (SHORT)HIWORD(wParam);
 906       if(abs(delta) >= WHEEL_DELTA && nScrollLines != 0)
 907       {
 908         p.x = LOWORD(lParam);
 909         p.y = HIWORD(lParam);
 910         return HEXEDIT_WM_MOUSEWHEEL(hed, nScrollLines * (delta / WHEEL_DELTA), LOWORD(wParam), &p);
 911       }
 912       break;
 913     }
 914
 915     case HEM_LOADBUFFER:
 916       return HEXEDIT_HEM_LOADBUFFER(hed, (PVOID)wParam, (DWORD)lParam);
 917
 918     case HEM_COPYBUFFER:
 919       return HEXEDIT_HEM_COPYBUFFER(hed, (PVOID)wParam, (DWORD)lParam);
 920
 921     case HEM_SETMAXBUFFERSIZE:
 922       return HEXEDIT_HEM_SETMAXBUFFERSIZE(hed, (DWORD)lParam);
 923
 924     case WM_SETFOCUS:
 925       return HEXEDIT_WM_SETFOCUS(hed);
 926
 927     case WM_KILLFOCUS:
 928       return HEXEDIT_WM_KILLFOCUS(hed);
 929
 930     case WM_GETDLGCODE:
 931       return HEXEDIT_WM_GETDLGCODE((LPMSG)lParam);
 932
 933     case WM_SETFONT:
 934       return HEXEDIT_WM_SETFONT(hed, (HFONT)wParam, (BOOL)LOWORD(lParam));
 935
 936     case WM_GETFONT:
 937       return HEXEDIT_WM_GETFONT(hed);
 938
 939     case WM_CREATE:
 940       return HEXEDIT_WM_CREATE(hed);
 941
 942     case WM_NCCREATE:
 943       if(!hed)
 944       {
 945         return HEXEDIT_WM_NCCREATE(hWnd, (CREATESTRUCT*)lParam);
 946       }
 947       break;
 948
 949     case WM_NCDESTROY:
 950       if(hed)
 951       {
 952         return HEXEDIT_WM_NCDESTROY(hed);
 953       }
 954       break;
 955   }
 956
 957   return CallWindowProc(DefWindowProc, hWnd, uMsg, wParam, lParam);
 958 }
 959