3 * Copyright (C) 1998, 1999, 2000, 2001 ReactOS Team
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21 * PROJECT: ReactOS user32.dll
22 * FILE: lib/user32/windows/input.c
24 * PROGRAMMER: Casper S. Hornstrup (chorns@users.sourceforge.net)
26 * 09-05-2001 CSH Created
29 /* INCLUDES ******************************************************************/
36 /* FUNCTIONS *****************************************************************/
48 CONST LPINT lpnTabStopPositions)
65 CONST LPINT lpnTabStopPositions)
71 /*********************************************************************
76 * Copyright 1993, 1994 Alexandre Julliard
77 * Copyright 2002 Bill Medland
80 * How many buffers to use
81 * While processing in DrawText there are potentially three different forms
82 * of the text that need to be held. How are they best held?
83 * 1. The original text is needed, of course, to see what to display.
84 * 2. The text that will be returned to the user if the DT_MODIFYSTRING is
86 * 3. The buffered text that is about to be displayed e.g. the current line.
87 * Typically this will exclude the ampersands used for prefixing etc.
90 * a. If the buffered text to be displayed includes the ampersands then
91 * we will need special measurement and draw functions that will ignore
92 * the ampersands (e.g. by copying to a buffer without the prefix and
93 * then using the normal forms). This may involve less space but may
94 * require more processing. e.g. since a line containing tabs may
95 * contain several underlined characters either we need to carry around
96 * a list of prefix locations or we may need to locate them several
98 * b. If we actually directly modify the "original text" as we go then we
99 * will need some special "caching" to handle the fact that when we
100 * ellipsify the text the ellipsis may modify the next line of text,
101 * which we have not yet processed. (e.g. ellipsification of a W at the
102 * end of a line will overwrite the W, the \n and the first character of
103 * the next line, and a \0 will overwrite the second. Try it!!)
105 * Option 1. Three separate storages. (To be implemented)
106 * If DT_MODIFYSTRING is in effect then allocate an extra buffer to hold
107 * the edited string in some form, either as the string itself or as some
108 * sort of "edit list" to be applied just before returning.
109 * Use a buffer that holds the ellipsified current line sans ampersands
110 * and accept the need occasionally to recalculate the prefixes (if
111 * DT_EXPANDTABS and not DT_NOPREFIX and not DT_HIDEPREFIX)
120 #define FORWARD_SLASH '/'
121 #define BACK_SLASH '\\'
123 static const WCHAR ELLIPSISW[] = {'.','.','.', 0};
125 typedef struct tag_ellipsis_data
133 /*********************************************************************
134 * TEXT_Ellipsify (static)
136 * Add an ellipsis to the end of the given string whilst ensuring it fits.
138 * If the ellipsis alone doesn't fit then it will be returned anyway.
140 * See Also TEXT_PathEllipsify
143 * hdc [in] The handle to the DC that defines the font.
144 * str [in/out] The string that needs to be modified.
145 * max_str [in] The dimension of str (number of WCHAR).
146 * len_str [in/out] The number of characters in str
147 * width [in] The maximum width permitted (in logical coordinates)
148 * size [out] The dimensions of the text
149 * modstr [out] The modified form of the string, to be returned to the
150 * calling program. It is assumed that the caller has
151 * made sufficient space available so we don't need to
152 * know the size of the space. This pointer may be NULL if
153 * the modified string is not required.
154 * len_before [out] The number of characters before the ellipsis.
155 * len_ellip [out] The number of characters in the ellipsis.
157 * See for example Microsoft article Q249678.
159 * For now we will simply use three dots rather than worrying about whether
160 * the font contains an explicit ellipsis character.
162 static void TEXT_Ellipsify (HDC hdc, WCHAR *str, unsigned int max_len,
163 unsigned int *len_str, int width, SIZE *size,
165 int *len_before, int *len_ellip)
167 unsigned int len_ellipsis;
168 unsigned int lo, mid, hi;
170 len_ellipsis = wcslen (ELLIPSISW);
171 if (len_ellipsis > max_len) len_ellipsis = max_len;
172 if (*len_str > max_len - len_ellipsis)
173 *len_str = max_len - len_ellipsis;
175 /* First do a quick binary search to get an upper bound for *len_str. */
177 GetTextExtentExPointW(hdc, str, *len_str, width, NULL, NULL, size) &&
180 for (lo = 0, hi = *len_str; lo < hi; )
183 if (!GetTextExtentExPointW(hdc, str, mid, width, NULL, NULL, size))
185 if (size->cx > width)
192 /* Now this should take only a couple iterations at most. */
195 wcsncpy (str + *len_str, ELLIPSISW, len_ellipsis);
197 if (!GetTextExtentExPointW (hdc, str, *len_str + len_ellipsis, width,
198 NULL, NULL, size)) break;
200 if (!*len_str || size->cx <= width) break;
204 *len_ellip = len_ellipsis;
205 *len_before = *len_str;
206 *len_str += len_ellipsis;
210 wcsncpy (modstr, str, *len_str);
211 *(str+*len_str) = '\0';
215 /*********************************************************************
216 * TEXT_PathEllipsify (static)
218 * Add an ellipsis to the provided string in order to make it fit within
219 * the width. The ellipsis is added as specified for the DT_PATH_ELLIPSIS
222 * See Also TEXT_Ellipsify
225 * hdc [in] The handle to the DC that defines the font.
226 * str [in/out] The string that needs to be modified
227 * max_str [in] The dimension of str (number of WCHAR).
228 * len_str [in/out] The number of characters in str
229 * width [in] The maximum width permitted (in logical coordinates)
230 * size [out] The dimensions of the text
231 * modstr [out] The modified form of the string, to be returned to the
232 * calling program. It is assumed that the caller has
233 * made sufficient space available so we don't need to
234 * know the size of the space. This pointer may be NULL if
235 * the modified string is not required.
236 * pellip [out] The ellipsification results
238 * For now we will simply use three dots rather than worrying about whether
239 * the font contains an explicit ellipsis character.
241 * The following applies, I think to Win95. We will need to extend it for
242 * Win98 which can have both path and end ellipsis at the same time (e.g.
243 * C:\MyLongFileName.Txt becomes ...\MyLongFileN...)
245 * The resulting string consists of as much as possible of the following:
246 * 1. The ellipsis itself
247 * 2. The last \ or / of the string (if any)
248 * 3. Everything after the last \ or / of the string (if any) or the whole
249 * string if there is no / or \. I believe that under Win95 this would
250 * include everything even though some might be clipped off the end whereas
251 * under Win98 that might be ellipsified too.
252 * Yet to be investigated is whether this would include wordbreaking if the
253 * filename is more than 1 word and splitting if DT_EDITCONTROL was in
254 * effect. (If DT_EDITCONTROL is in effect then on occasions text will be
255 * broken within words).
256 * 4. All the stuff before the / or \, which is placed before the ellipsis.
258 static void TEXT_PathEllipsify (HDC hdc, WCHAR *str, unsigned int max_len,
259 unsigned int *len_str, int width, SIZE *size,
260 WCHAR *modstr, ellipsis_data *pellip)
262 unsigned int len_ellipsis;
265 WCHAR *lastBkSlash, *lastFwdSlash, *lastSlash;
267 len_ellipsis = wcslen (ELLIPSISW);
268 if (!max_len) return;
269 if (len_ellipsis >= max_len) len_ellipsis = max_len - 1;
270 if (*len_str + len_ellipsis >= max_len)
271 *len_str = max_len - len_ellipsis-1;
272 /* Hopefully this will never happen, otherwise it would probably lose
273 * the wrong character
275 str[*len_str] = '\0'; /* to simplify things */
277 lastBkSlash = wcsrchr (str, BACK_SLASH);
278 lastFwdSlash = wcsrchr (str, FORWARD_SLASH);
279 lastSlash = lastBkSlash > lastFwdSlash ? lastBkSlash : lastFwdSlash;
280 if (!lastSlash) lastSlash = str;
281 len_trailing = *len_str - (lastSlash - str);
283 /* overlap-safe movement to the right */
284 memmove (lastSlash+len_ellipsis, lastSlash, len_trailing * sizeof(WCHAR));
285 wcsncpy (lastSlash, ELLIPSISW, len_ellipsis);
286 len_trailing += len_ellipsis;
287 /* From this point on lastSlash actually points to the ellipsis in front
288 * of the last slash and len_trailing includes the ellipsis
294 if (!GetTextExtentExPointW (hdc, str, *len_str + len_ellipsis, width,
295 NULL, NULL, size)) break;
297 if (lastSlash == str || size->cx <= width) break;
299 /* overlap-safe movement to the left */
300 memmove (lastSlash-1, lastSlash, len_trailing * sizeof(WCHAR));
307 pellip->before = lastSlash-str;
308 pellip->len = len_ellipsis;
309 pellip->under = len_under;
310 pellip->after = len_trailing - len_ellipsis;
311 *len_str += len_ellipsis;
315 wcsncpy (modstr, str, *len_str);
316 *(str+*len_str) = '\0';
320 /*********************************************************************
321 * TEXT_WordBreak (static)
323 * Perform wordbreak processing on the given string
325 * Assumes that DT_WORDBREAK has been specified and not all the characters
326 * fit. Note that this function should even be called when the first character
327 * that doesn't fit is known to be a space or tab, so that it can swallow them.
329 * Note that the Windows processing has some strange properties.
330 * 1. If the text is left-justified and there is room for some of the spaces
331 * that follow the last word on the line then those that fit are included on
333 * 2. If the text is centred or right-justified and there is room for some of
334 * the spaces that follow the last word on the line then all but one of those
335 * that fit are included on the line.
336 * 3. (Reasonable behaviour) If the word breaking causes a space to be the first
337 * character of a new line it will be skipped.
340 * hdc [in] The handle to the DC that defines the font.
341 * str [in/out] The string that needs to be broken.
342 * max_str [in] The dimension of str (number of WCHAR).
343 * len_str [in/out] The number of characters in str
344 * width [in] The maximum width permitted
345 * format [in] The format flags in effect
346 * chars_fit [in] The maximum number of characters of str that are already
347 * known to fit; chars_fit+1 is known not to fit.
348 * chars_used [out] The number of characters of str that have been "used" and
349 * do not need to be included in later text. For example this will
350 * include any spaces that have been discarded from the start of
352 * size [out] The size of the returned text in logical coordinates
354 * Pedantic assumption - Assumes that the text length is monotonically
355 * increasing with number of characters (i.e. no weird kernings)
359 * Work back from the last character that did fit to either a space or the last
360 * character of a word, whichever is met first.
361 * If there was one or the first character didn't fit then
362 * If the text is centred or right justified and that one character was a
363 * space then break the line before that character
364 * Otherwise break the line after that character
365 * and if the next character is a space then discard it.
366 * Suppose there was none (and the first character did fit).
367 * If Break Within Word is permitted
368 * break the word after the last character that fits (there must be
369 * at least one; none is caught earlier).
371 * discard any trailing space.
372 * include the whole word; it may be ellipsified later
374 * Break Within Word is permitted under a set of circumstances that are not
375 * totally clear yet. Currently our best guess is:
376 * If DT_EDITCONTROL is in effect and neither DT_WORD_ELLIPSIS nor
377 * DT_PATH_ELLIPSIS is
380 static void TEXT_WordBreak (HDC hdc, WCHAR *str, unsigned int max_str,
381 unsigned int *len_str,
382 int width, int format, unsigned int chars_fit,
383 unsigned int *chars_used, SIZE *size)
387 assert (format & DT_WORDBREAK);
388 assert (chars_fit < *len_str);
390 /* Work back from the last character that did fit to either a space or the
391 * last character of a word, whichever is met first.
393 p = str + chars_fit; /* The character that doesn't fit */
396 ; /* we pretend that it fits anyway */
397 else if (*p == SPACE) /* chars_fit < *len_str so this is valid */
398 p--; /* the word just fitted */
401 while (p > str && *(--p) != SPACE)
403 word_fits = (p != str || *p == SPACE);
405 /* If there was one or the first character didn't fit then */
409 /* break the line before/after that character */
410 if (!(format & (DT_RIGHT | DT_CENTER)) || *p != SPACE)
412 next_is_space = (unsigned int) (p - str) < *len_str && *p == SPACE;
414 /* and if the next character is a space then discard it. */
415 *chars_used = *len_str;
419 /* Suppose there was none. */
422 if ((format & (DT_EDITCONTROL | DT_WORD_ELLIPSIS | DT_PATH_ELLIPSIS)) ==
425 /* break the word after the last character that fits (there must be
426 * at least one; none is caught earlier).
428 *len_str = chars_fit;
429 *chars_used = chars_fit;
431 /* FIXME - possible error. Since the next character is now removed
432 * this could make the text longer so that it no longer fits, and
433 * so we need a loop to test and shrink.
439 /* discard any trailing space. */
440 const WCHAR *e = str + *len_str;
442 while (p < e && *p != SPACE)
444 *chars_used = p - str;
445 if (p < e) /* i.e. loop failed because *p == SPACE */
448 /* include the whole word; it may be ellipsified later */
450 /* Possible optimisation; if DT_WORD_ELLIPSIS only use chars_fit+1
451 * so that it will be too long
455 /* Remeasure the string */
456 GetTextExtentExPointW (hdc, str, *len_str, 0, NULL, NULL, size);
459 /*********************************************************************
462 * Skip over the given number of characters, bearing in mind prefix
463 * substitution and the fact that a character may take more than one
464 * WCHAR (Unicode surrogates are two words long) (and there may have been
468 * new_count [out] The updated count
469 * new_str [out] The updated pointer
470 * start_count [in] The count of remaining characters corresponding to the
471 * start of the string
472 * start_str [in] The starting point of the string
473 * max [in] The number of characters actually in this segment of the
474 * string (the & counts)
475 * n [in] The number of characters to skip (if prefix then
477 * prefix [in] Apply prefix substitution
483 * There must be at least n characters in the string
484 * We need max because the "line" may have ended with a & followed by a tab
485 * or newline etc. which we don't want to swallow
488 static void TEXT_SkipChars (int *new_count, const WCHAR **new_str,
489 int start_count, const WCHAR *start_str,
490 int max, int n, int prefix)
492 /* This is specific to wide characters, MSDN doesn't say anything much
493 * about Unicode surrogates yet and it isn't clear if _wcsinc will
494 * correctly handle them so we'll just do this the easy way for now
499 const WCHAR *str_on_entry = start_str;
503 if (*start_str++ == PREFIX && max--)
506 start_count -= (start_str - str_on_entry);
513 *new_str = start_str;
514 *new_count = start_count;
517 /*********************************************************************
520 * Reanalyse the text to find the prefixed character. This is called when
521 * wordbreaking or ellipsification has shortened the string such that the
522 * previously noted prefixed character is no longer visible.
525 * str [in] The original string segment (including all characters)
526 * ns [in] The number of characters in str (including prefixes)
527 * pe [in] The ellipsification data
530 * The prefix offset within the new string segment (the one that contains the
531 * ellipses and does not contain the prefix characters) (-1 if none)
534 static int TEXT_Reprefix (const WCHAR *str, unsigned int ns,
535 const ellipsis_data *pe)
539 unsigned int n = pe->before + pe->under + pe->after;
543 if (i == (unsigned int) pe->before)
545 /* Reached the path ellipsis; jump over it */
546 if (ns < (unsigned int) pe->under) break;
550 if (!pe->after) break; /* Nothing after the path ellipsis */
554 if (*str++ == PREFIX)
558 result = (i < (unsigned int) pe->before || pe->under == 0) ? i : i - pe->under + pe->len;
559 /* pe->len may be non-zero while pe_under is zero */
569 /*********************************************************************
570 * Returns true if and only if the remainder of the line is a single
571 * newline representation or nothing
574 static int remainder_is_none_or_newline (int num_chars, const WCHAR *str)
576 if (!num_chars) return TRUE;
577 if (*str != LF && *str != CR) return FALSE;
578 if (!--num_chars) return TRUE;
579 if (*str == *(str+1)) return FALSE;
581 if (*str != CR && *str != LF) return FALSE;
582 if (--num_chars) return FALSE;
586 /*********************************************************************
587 * Return next line of text from a string.
589 * hdc - handle to DC.
590 * str - string to parse into lines.
591 * count - length of str.
592 * dest - destination in which to return line.
593 * len - dest buffer size in chars on input, copied length into dest on output.
594 * width - maximum width of line in pixels.
595 * format - format type passed to DrawText.
596 * retsize - returned size of the line in pixels.
597 * last_line - TRUE if is the last line that will be processed
598 * p_retstr - If DT_MODIFYSTRING this points to a cursor in the buffer in which
599 * the return string is built.
600 * tabwidth - The width of a tab in logical coordinates
601 * pprefix_offset - Here is where we return the offset within dest of the first
602 * prefixed (underlined) character. -1 is returned if there
603 * are none. Note that there may be more; the calling code
604 * will need to use TEXT_Reprefix to find any later ones.
605 * pellip - Here is where we return the information about any ellipsification
606 * that was carried out. Note that if tabs are being expanded then
607 * this data will correspond to the last text segment actually
608 * returned in dest; by definition there would not have been any
609 * ellipsification in earlier text segments of the line.
611 * Returns pointer to next char in str after end of the line
612 * or NULL if end of str reached.
614 static const WCHAR *TEXT_NextLineW( HDC hdc, const WCHAR *str, int *count,
615 WCHAR *dest, int *len, int width, DWORD format,
616 SIZE *retsize, int last_line, WCHAR **p_retstr,
617 int tabwidth, int *pprefix_offset,
618 ellipsis_data *pellip)
624 int seg_i, seg_count, seg_j;
631 *pprefix_offset = -1;
633 /* For each text segment in the line */
639 /* Skip any leading tabs */
641 if (str[i] == TAB && (format & DT_EXPANDTABS))
643 plen = ((plen/tabwidth)+1)*tabwidth;
644 (*count)--; if (j < maxl) dest[j++] = str[i++]; else i++;
645 while (*count && str[i] == TAB)
648 (*count)--; if (j < maxl) dest[j++] = str[i++]; else i++;
653 /* Now copy as far as the next tab or cr/lf or eos */
660 (str[i] != TAB || !(format & DT_EXPANDTABS)) &&
661 ((str[i] != CR && str[i] != LF) || (format & DT_SINGLELINE)))
663 if (str[i] == PREFIX && !(format & DT_NOPREFIX) && *count > 1)
665 (*count)--, i++; /* Throw away the prefix itself */
666 if (str[i] == PREFIX)
668 /* Swallow it before we see it again */
669 (*count)--; if (j < maxl) dest[j++] = str[i++]; else i++;
671 else if (*pprefix_offset == -1 || *pprefix_offset >= seg_j)
675 /* else the previous prefix was in an earlier segment of the
676 * line; we will leave it to the drawing code to catch this
682 (*count)--; if (j < maxl) dest[j++] = str[i++]; else i++;
687 /* Measure the whole text segment and possibly WordBreak and
691 j_in_seg = j - seg_j;
692 max_seg_width = width - plen;
693 GetTextExtentExPointW (hdc, dest + seg_j, j_in_seg, max_seg_width, &num_fit, NULL, &size);
695 /* The Microsoft handling of various combinations of formats is weird.
696 * The following may very easily be incorrect if several formats are
697 * combined, and may differ between versions (to say nothing of the
698 * several bugs in the Microsoft versions).
701 line_fits = (num_fit >= j_in_seg);
702 if (!line_fits && (format & DT_WORDBREAK))
706 TEXT_WordBreak (hdc, dest+seg_j, maxl-seg_j, &j_in_seg,
707 max_seg_width, format, num_fit, &chars_used, &size);
708 line_fits = (size.cx <= max_seg_width);
709 /* and correct the counts */
710 TEXT_SkipChars (count, &s, seg_count, str+seg_i, i-seg_i,
711 chars_used, !(format & DT_NOPREFIX));
715 pellip->before = j_in_seg;
720 if (!line_fits && (format & DT_PATH_ELLIPSIS))
722 TEXT_PathEllipsify (hdc, dest + seg_j, maxl-seg_j, &j_in_seg,
723 max_seg_width, &size, *p_retstr, pellip);
724 line_fits = (size.cx <= max_seg_width);
727 /* NB we may end up ellipsifying a word-broken or path_ellipsified
729 if ((!line_fits && (format & DT_WORD_ELLIPSIS)) ||
730 ((format & DT_END_ELLIPSIS) &&
731 ((last_line && *count) ||
732 (remainder_is_none_or_newline (*count, &str[i]) && !line_fits))))
734 int before, len_ellipsis;
735 TEXT_Ellipsify (hdc, dest + seg_j, maxl-seg_j, &j_in_seg,
736 max_seg_width, &size, *p_retstr, &before, &len_ellipsis);
737 if (before > pellip->before)
739 /* We must have done a path ellipsis too */
740 pellip->after = before - pellip->before - pellip->len;
741 /* Leave the len as the length of the first ellipsis */
745 /* If we are here after a path ellipsification it must be
746 * because even the ellipsis itself didn't fit.
748 assert (pellip->under == 0 && pellip->after == 0);
749 pellip->before = before;
750 pellip->len = len_ellipsis;
751 /* pellip->after remains as zero as does
755 line_fits = (size.cx <= max_seg_width);
758 /* As an optimisation if we have ellipsified and we are expanding
759 * tabs and we haven't reached the end of the line we can skip to it
760 * now rather than going around the loop again.
762 if ((format & DT_EXPANDTABS) && ellipsified)
764 if (format & DT_SINGLELINE)
768 while ((*count) && str[i] != CR && str[i] != LF)
775 j = seg_j + j_in_seg;
776 if (*pprefix_offset >= seg_j + pellip->before)
778 *pprefix_offset = TEXT_Reprefix (str + seg_i, i - seg_i, pellip);
779 if (*pprefix_offset != -1)
780 *pprefix_offset += seg_j;
784 if (size.cy > retsize->cy)
785 retsize->cy = size.cy;
791 else if (str[i] == CR || str[i] == LF)
794 if (*count && (str[i] == CR || str[i] == LF) && str[i] != str[i-1])
800 /* else it was a Tab and we go around again */
812 /***********************************************************************
813 * TEXT_DrawUnderscore
815 * Draw the underline under the prefixed character
818 * hdc [in] The handle of the DC for drawing
819 * x [in] The x location of the line segment (logical coordinates)
820 * y [in] The y location of where the underscore should appear
821 * (logical coordinates)
822 * str [in] The text of the line segment
823 * offset [in] The offset of the underscored character within str
826 static void TEXT_DrawUnderscore (HDC hdc, int x, int y, const WCHAR *str, int offset)
834 GetTextExtentPointW (hdc, str, offset, &size);
835 prefix_x = x + size.cx;
836 GetTextExtentPointW (hdc, str, offset+1, &size);
837 prefix_end = x + size.cx - 1;
838 /* The above method may eventually be slightly wrong due to kerning etc. */
840 hpen = CreatePen (PS_SOLID, 1, GetTextColor (hdc));
841 oldPen = SelectObject (hdc, hpen);
842 MoveToEx (hdc, prefix_x, y, NULL);
843 LineTo (hdc, prefix_end, y);
844 SelectObject (hdc, oldPen);
848 /***********************************************************************
849 * DrawTextExW (USER32.@)
851 * The documentation on the extra space required for DT_MODIFYSTRING at MSDN
852 * is not quite complete, especially with regard to \0. We will assume that
853 * the returned string could have a length of up to i_count+3 and also have
854 * a trailing \0 (which would be 4 more than a not-null-terminated string but
855 * 3 more than a null-terminated string). If this is not so then increase
856 * the allowance in DrawTextExA.
858 #define MAX_STATIC_BUFFER 1024
863 DrawTextExW( HDC hdc, LPWSTR str, INT i_count,
864 LPRECT rect, UINT flags, LPDRAWTEXTPARAMS dtp )
868 WCHAR *retstr, *p_retstr;
870 static WCHAR line[MAX_STATIC_BUFFER];
871 int len, lh, count=i_count;
873 int lmargin = 0, rmargin = 0;
874 int x = rect->left, y = rect->top;
875 int width = rect->right - rect->left;
878 int tabwidth /* to keep gcc happy */ = 0;
883 TRACE("%s, %d , [(%d,%d),(%d,%d)]\n", debugstr_wn (str, count), count,
884 rect->left, rect->top, rect->right, rect->bottom);
886 if (dtp) TRACE("Params: iTabLength=%d, iLeftMargin=%d, iRightMargin=%d\n",
887 dtp->iTabLength, dtp->iLeftMargin, dtp->iRightMargin);
891 if (count == -1) count = wcslen(str);
892 if (count == 0) return 0;
895 if (flags & DT_SINGLELINE)
896 flags &= ~DT_WORDBREAK;
898 GetTextMetricsW(hdc, &tm);
899 if (flags & DT_EXTERNALLEADING)
900 lh = tm.tmHeight + tm.tmExternalLeading;
906 lmargin = dtp->iLeftMargin * tm.tmAveCharWidth;
907 rmargin = dtp->iRightMargin * tm.tmAveCharWidth;
908 if (!(flags & (DT_CENTER | DT_RIGHT)))
910 dtp->uiLengthDrawn = 0; /* This param RECEIVES number of chars processed */
913 if (flags & DT_EXPANDTABS)
915 int tabstop = ((flags & DT_TABSTOP) && dtp) ? dtp->iTabLength : 8;
916 tabwidth = tm.tmAveCharWidth * tabstop;
919 if (flags & DT_CALCRECT) flags |= DT_NOCLIP;
921 if (flags & DT_MODIFYSTRING)
923 size_retstr = (count + 4) * sizeof (WCHAR);
924 retstr = HeapAlloc(GetProcessHeap(), 0, size_retstr);
925 if (!retstr) return 0;
926 memcpy (retstr, str, size_retstr);
937 len = MAX_STATIC_BUFFER;
938 last_line = !(flags & DT_NOCLIP) && y + ((flags & DT_EDITCONTROL) ? 2*lh-1 : lh) > rect->bottom;
939 strPtr = TEXT_NextLineW(hdc, strPtr, &count, line, &len, width, flags, &size, last_line, &p_retstr, tabwidth, &prefix_offset, &ellip);
941 if (flags & DT_CENTER) x = (rect->left + rect->right -
943 else if (flags & DT_RIGHT) x = rect->right - size.cx;
945 if (flags & DT_SINGLELINE)
947 if (flags & DT_VCENTER) y = rect->top +
948 (rect->bottom - rect->top) / 2 - size.cy / 2;
949 else if (flags & DT_BOTTOM) y = rect->bottom - size.cy;
952 if (!(flags & DT_CALCRECT))
954 const WCHAR *str = line;
960 if ((flags & DT_EXPANDTABS))
963 p = str; while (p < str+len && *p != TAB) p++;
965 if (len_seg != len && !GetTextExtentPointW(hdc, str, len_seg, &size))
971 if (!ExtTextOutW( hdc, xseg, y,
972 ((flags & DT_NOCLIP) ? 0 : ETO_CLIPPED) |
973 ((flags & DT_RTLREADING) ? ETO_RTLREADING : 0),
974 rect, str, len_seg, NULL )) return 0;
975 if (prefix_offset != -1 && prefix_offset < len_seg)
977 TEXT_DrawUnderscore (hdc, xseg, y + tm.tmAscent + 1, str, prefix_offset);
983 assert ((flags & DT_EXPANDTABS) && *str == TAB);
985 xseg += ((size.cx/tabwidth)+1)*tabwidth;
986 if (prefix_offset != -1)
988 if (prefix_offset < len_seg)
990 /* We have just drawn an underscore; we ought to
991 * figure out where the next one is. I am going
992 * to leave it for now until I have a better model
993 * for the line, which will make reprefixing easier.
994 * This is where ellip would be used.
999 prefix_offset -= len_seg;
1004 else if (size.cx > max_width)
1005 max_width = size.cx;
1009 dtp->uiLengthDrawn += len;
1011 while (strPtr && !last_line);
1013 if (flags & DT_CALCRECT)
1015 rect->right = rect->left + max_width;
1018 rect->right += lmargin + rmargin;
1022 memcpy (str, retstr, size_retstr);
1023 HeapFree (GetProcessHeap(), 0, retstr);
1025 return y - rect->top;
1028 /***********************************************************************
1029 * DrawTextExA (USER32.@)
1031 * If DT_MODIFYSTRING is specified then there must be room for up to
1032 * 4 extra characters. We take great care about just how much modified
1038 DrawTextExA( HDC hdc, LPSTR str, INT count,
1039 LPRECT rect, UINT flags, LPDRAWTEXTPARAMS dtp )
1050 if (count == -1) count = strlen(str);
1051 if (!count) return 0;
1052 wcount = MultiByteToWideChar( CP_ACP, 0, str, count, NULL, 0 );
1055 if (flags & DT_MODIFYSTRING)
1060 wstr = HeapAlloc(GetProcessHeap(), 0, wmax * sizeof(WCHAR));
1063 MultiByteToWideChar( CP_ACP, 0, str, count, wstr, wcount );
1064 if (flags & DT_MODIFYSTRING)
1065 for (i=4, p=wstr+wcount; i--; p++) *p=0xFFFE;
1066 /* Initialise the extra characters so that we can see which ones
1067 * change. U+FFFE is guaranteed to be not a unicode character and
1068 * so will not be generated by DrawTextEx itself.
1070 ret = DrawTextExW( hdc, wstr, wcount, rect, flags, NULL );
1071 if (flags & DT_MODIFYSTRING)
1073 /* Unfortunately the returned string may contain multiple \0s
1074 * and so we need to measure it ourselves.
1076 for (i=4, p=wstr+wcount; i-- && *p != 0xFFFE; p++) wcount++;
1077 WideCharToMultiByte( CP_ACP, 0, wstr, wcount, str, amax, NULL, NULL );
1079 HeapFree(GetProcessHeap(), 0, wstr);
1084 /***********************************************************************
1085 * DrawTextW (USER32.@)
1090 DrawTextW( HDC hdc, LPCWSTR str, INT count, LPRECT rect, UINT flags )
1094 memset (&dtp, 0, sizeof(dtp));
1095 if (flags & DT_TABSTOP)
1097 dtp.iTabLength = (flags >> 8) && 0xff;
1098 flags &= 0xffff00ff;
1100 return DrawTextExW(hdc, (LPWSTR)str, count, rect, flags, &dtp);
1103 /***********************************************************************
1104 * DrawTextA (USER32.@)
1109 DrawTextA( HDC hdc, LPCSTR str, INT count, LPRECT rect, UINT flags )
1113 memset (&dtp, 0, sizeof(dtp));
1114 if (flags & DT_TABSTOP)
1116 dtp.iTabLength = (flags >> 8) && 0xff;
1117 flags &= 0xffff00ff;
1119 return DrawTextExA( hdc, (LPSTR)str, count, rect, flags, &dtp );