1 /* 2 This file is part of Konsole, KDE's terminal. 3 4 Copyright 2007-2008 by Robert Knight <robertknight@gmail.com> 5 Copyright 1997,1998 by Lars Doelle <lars.doelle@on-line.de> 6 7 This program is free software; you can redistribute it and/or modify 8 it under the terms of the GNU General Public License as published by 9 the Free Software Foundation; either version 2 of the License, or 10 (at your option) any later version. 11 12 This program is distributed in the hope that it will be useful, 13 but WITHOUT ANY WARRANTY; without even the implied warranty of 14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 GNU General Public License for more details. 16 17 You should have received a copy of the GNU General Public License 18 along with this program; if not, write to the Free Software 19 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 20 02110-1301 USA. 21 */ 22 23 #ifndef SCREEN_H 24 #define SCREEN_H 25 26 // Qt 27 #include <QRect> 28 #include <QTextStream> 29 #include <QVarLengthArray> 30 31 // Konsole 32 #include "Character.h" 33 #include "History.h" 34 35 #define MODE_Origin 0 36 #define MODE_Wrap 1 37 #define MODE_Insert 2 38 #define MODE_Screen 3 39 #define MODE_Cursor 4 40 #define MODE_NewLine 5 41 #define MODES_SCREEN 6 42 43 namespace Konsole 44 { 45 46 class TerminalCharacterDecoder; 47 48 /** 49 \brief An image of characters with associated attributes. 50 51 The terminal emulation ( Emulation ) receives a serial stream of 52 characters from the program currently running in the terminal. 53 From this stream it creates an image of characters which is ultimately 54 rendered by the display widget ( TerminalDisplay ). Some types of emulation 55 may have more than one screen image. 56 57 getImage() is used to retrieve the currently visible image 58 which is then used by the display widget to draw the output from the 59 terminal. 60 61 The number of lines of output history which are kept in addition to the current 62 screen image depends on the history scroll being used to store the output. 63 The scroll is specified using setScroll() 64 The output history can be retrieved using writeToStream() 65 66 The screen image has a selection associated with it, specified using 67 setSelectionStart() and setSelectionEnd(). The selected text can be retrieved 68 using selectedText(). When getImage() is used to retrieve the visible image, 69 characters which are part of the selection have their colours inverted. 70 */ 71 class Screen 72 { 73 public: 74 /** Construct a new screen image of size @p lines by @p columns. */ 75 Screen(int lines, int columns); 76 ~Screen(); 77 78 // VT100/2 Operations 79 // Cursor Movement 80 81 /** 82 * Move the cursor up by @p n lines. The cursor will stop at the 83 * top margin. 84 */ 85 void cursorUp(int n); 86 /** 87 * Move the cursor down by @p n lines. The cursor will stop at the 88 * bottom margin. 89 */ 90 void cursorDown(int n); 91 /** 92 * Move the cursor to the left by @p n columns. 93 * The cursor will stop at the first column. 94 */ 95 void cursorLeft(int n); 96 /** 97 * Move the cursor to the right by @p n columns. 98 * The cursor will stop at the right-most column. 99 */ 100 void cursorRight(int n); 101 /** Position the cursor on line @p y. */ 102 void setCursorY(int y); 103 /** Position the cursor at column @p x. */ 104 void setCursorX(int x); 105 /** Position the cursor at line @p y, column @p x. */ 106 void setCursorYX(int y, int x); 107 /** 108 * Sets the margins for scrolling the screen. 109 * 110 * \param topLine The top line of the new scrolling margin. 111 * \param bottomLine The bottom line of the new scrolling margin. 112 */ 113 void setMargins(int topLine , int bottomLine); 114 /** Returns the top line of the scrolling region. */ 115 int topMargin() const; 116 /** Returns the bottom line of the scrolling region. */ 117 int bottomMargin() const; 118 119 /** 120 * Resets the scrolling margins back to the top and bottom lines 121 * of the screen. 122 */ 123 void setDefaultMargins(); 124 125 /** 126 * Moves the cursor down one line, if the MODE_NewLine mode 127 * flag is enabled then the cursor is returned to the leftmost 128 * column first. 129 * 130 * Equivalent to NextLine() if the MODE_NewLine flag is set 131 * or index() otherwise. 132 */ 133 void newLine(); 134 /** 135 * Moves the cursor down one line and positions it at the beginning 136 * of the line. Equivalent to calling Return() followed by index() 137 */ 138 void nextLine(); 139 140 /** 141 * Move the cursor down one line. If the cursor is on the bottom 142 * line of the scrolling region (as returned by bottomMargin()) the 143 * scrolling region is scrolled up by one line instead. 144 */ 145 void index(); 146 /** 147 * Move the cursor up one line. If the cursor is on the top line 148 * of the scrolling region (as returned by topMargin()) the scrolling 149 * region is scrolled down by one line instead. 150 */ 151 void reverseIndex(); 152 153 /** 154 * Scroll the scrolling region of the screen up by @p n lines. 155 * The scrolling region is initially the whole screen, but can be changed 156 * using setMargins() 157 */ 158 void scrollUp(int n); 159 /** 160 * Scroll the scrolling region of the screen down by @p n lines. 161 * The scrolling region is initially the whole screen, but can be changed 162 * using setMargins() 163 */ 164 void scrollDown(int n); 165 /** 166 * Moves the cursor to the beginning of the current line. 167 * Equivalent to setCursorX(0) 168 */ 169 void toStartOfLine(); 170 /** 171 * Moves the cursor one column to the left and erases the character 172 * at the new cursor position. 173 */ 174 void backspace(); 175 /** Moves the cursor @p n tab-stops to the right. */ 176 void tab(int n = 1); 177 /** Moves the cursor @p n tab-stops to the left. */ 178 void backtab(int n); 179 180 // Editing 181 182 /** 183 * Erase @p n characters beginning from the current cursor position. 184 * This is equivalent to over-writing @p n characters starting with the current 185 * cursor position with spaces. 186 * If @p n is 0 then one character is erased. 187 */ 188 void eraseChars(int n); 189 /** 190 * Delete @p n characters beginning from the current cursor position. 191 * If @p n is 0 then one character is deleted. 192 */ 193 void deleteChars(int n); 194 /** 195 * Insert @p n blank characters beginning from the current cursor position. 196 * The position of the cursor is not altered. 197 * If @p n is 0 then one character is inserted. 198 */ 199 void insertChars(int n); 200 /** 201 * Removes @p n lines beginning from the current cursor position. 202 * The position of the cursor is not altered. 203 * If @p n is 0 then one line is removed. 204 */ 205 void deleteLines(int n); 206 /** 207 * Inserts @p lines beginning from the current cursor position. 208 * The position of the cursor is not altered. 209 * If @p n is 0 then one line is inserted. 210 */ 211 void insertLines(int n); 212 /** Clears all the tab stops. */ 213 void clearTabStops(); 214 /** Sets or removes a tab stop at the cursor's current column. */ 215 void changeTabStop(bool set); 216 217 /** Resets (clears) the specified screen @p mode. */ 218 void resetMode(int mode); 219 /** Sets (enables) the specified screen @p mode. */ 220 void setMode(int mode); 221 /** 222 * Saves the state of the specified screen @p mode. It can be restored 223 * using restoreMode() 224 */ 225 void saveMode(int mode); 226 /** Restores the state of a screen @p mode saved by calling saveMode() */ 227 void restoreMode(int mode); 228 /** Returns whether the specified screen @p mode is enabled or not .*/ 229 bool getMode(int mode) const; 230 231 /** 232 * Saves the current position and appearance (text color and style) of the cursor. 233 * It can be restored by calling restoreCursor() 234 */ 235 void saveCursor(); 236 /** Restores the position and appearance of the cursor. See saveCursor() */ 237 void restoreCursor(); 238 239 /** Clear the whole screen, moving the current screen contents into the history first. */ 240 void clearEntireScreen(); 241 /** 242 * Clear the area of the screen from the current cursor position to the end of 243 * the screen. 244 */ 245 void clearToEndOfScreen(); 246 /** 247 * Clear the area of the screen from the current cursor position to the start 248 * of the screen. 249 */ 250 void clearToBeginOfScreen(); 251 /** Clears the whole of the line on which the cursor is currently positioned. */ 252 void clearEntireLine(); 253 /** Clears from the current cursor position to the end of the line. */ 254 void clearToEndOfLine(); 255 /** Clears from the current cursor position to the beginning of the line. */ 256 void clearToBeginOfLine(); 257 258 /** Fills the entire screen with the letter 'E' */ 259 void helpAlign(); 260 261 /** 262 * Enables the given @p rendition flag. Rendition flags control the appearance 263 * of characters on the screen. 264 * 265 * \see Character::rendition 266 */ 267 void setRendition(int rendition); 268 /** 269 * Disables the given @p rendition flag. Rendition flags control the appearance 270 * of characters on the screen. 271 * 272 * \see Character::rendition 273 */ 274 void resetRendition(int rendition); 275 276 /** 277 * Sets the cursor's foreground color. 278 * \param space The color space used by the @p color argument 279 * \param color The new foreground color. The meaning of this depends on 280 * the color @p space used. 281 * 282 * \see CharacterColor 283 */ 284 void setForeColor(int space, int color); 285 /** 286 * Sets the cursor's background color. 287 * \param space The color space used by the @p color argumnet. 288 * \param color The new background color. The meaning of this depends on 289 * the color @p space used. 290 * 291 * \see CharacterColor 292 */ 293 void setBackColor(int space, int color); 294 /** 295 * Resets the cursor's color back to the default and sets the 296 * character's rendition flags back to the default settings. 297 */ 298 void setDefaultRendition(); 299 300 /** Returns the column which the cursor is positioned at. */ 301 int getCursorX() const; 302 /** Returns the line which the cursor is positioned on. */ 303 int getCursorY() const; 304 305 /** Clear the entire screen and move the cursor to the home position. 306 * Equivalent to calling clearEntireScreen() followed by home(). 307 */ 308 void clear(); 309 /** 310 * Sets the position of the cursor to the 'home' position at the top-left 311 * corner of the screen (0,0) 312 */ 313 void home(); 314 /** 315 * Resets the state of the screen. This resets the various screen modes 316 * back to their default states. The cursor style and colors are reset 317 * (as if setDefaultRendition() had been called) 318 * 319 * <ul> 320 * <li>Line wrapping is enabled.</li> 321 * <li>Origin mode is disabled.</li> 322 * <li>Insert mode is disabled.</li> 323 * <li>Cursor mode is enabled. TODO Document me</li> 324 * <li>Screen mode is disabled. TODO Document me</li> 325 * <li>New line mode is disabled. TODO Document me</li> 326 * </ul> 327 * 328 * If @p clearScreen is true then the screen contents are erased entirely, 329 * otherwise they are unaltered. 330 */ 331 void reset(bool clearScreen = true); 332 333 /** 334 * Displays a new character at the current cursor position. 335 * 336 * If the cursor is currently positioned at the right-edge of the screen and 337 * line wrapping is enabled then the character is added at the start of a new 338 * line below the current one. 339 * 340 * If the MODE_Insert screen mode is currently enabled then the character 341 * is inserted at the current cursor position, otherwise it will replace the 342 * character already at the current cursor position. 343 */ 344 void displayCharacter(unsigned short c); 345 346 // Do composition with last shown character FIXME: Not implemented yet for KDE 4 347 void compose(const QString& compose); 348 349 /** 350 * Resizes the image to a new fixed size of @p new_lines by @p new_columns. 351 * In the case that @p new_columns is smaller than the current number of columns, 352 * existing lines are not truncated. This prevents characters from being lost 353 * if the terminal display is resized smaller and then larger again. 354 * 355 * The top and bottom margins are reset to the top and bottom of the new 356 * screen size. Tab stops are also reset and the current selection is 357 * cleared. 358 */ 359 void resizeImage(int new_lines, int new_columns); 360 361 /** 362 * Returns the current screen image. 363 * The result is an array of Characters of size [getLines()][getColumns()] which 364 * must be freed by the caller after use. 365 * 366 * \param dest Buffer to copy the characters into 367 * \param size Size of @p dest in Characters 368 * \param startLine Index of first line to copy 369 * \param endLine Index of last line to copy 370 */ 371 void getImage( Character* dest , int size , int startLine , int endLine ) const; 372 373 /** 374 * Returns the additional attributes associated with lines in the image. 375 * The most important attribute is LINE_WRAPPED which specifies that the 376 * line is wrapped, 377 * other attributes control the size of characters in the line. 378 */ 379 QVector<LineProperty> getLineProperties( int startLine , int endLine ) const; 380 381 382 /** Returns the number of lines. */ getLines()383 int getLines() const 384 { return lines; } 385 /** Returns the number of columns. */ getColumns()386 int getColumns() const 387 { return columns; } 388 /** Returns the number of lines in the history buffer. */ 389 int getHistLines() const; 390 /** 391 * Sets the type of storage used to keep lines in the history. 392 * If @p copyPreviousScroll is true then the contents of the previous 393 * history buffer are copied into the new scroll. 394 */ 395 void setScroll(const HistoryType& , bool copyPreviousScroll = true); 396 /** Returns the type of storage used to keep lines in the history. */ 397 const HistoryType& getScroll() const; 398 /** 399 * Returns true if this screen keeps lines that are scrolled off the screen 400 * in a history buffer. 401 */ 402 bool hasScroll() const; 403 404 /** 405 * Sets the start of the selection. 406 * 407 * \param column The column index of the first character in the selection. 408 * \param line The line index of the first character in the selection. 409 * \param blockSelectionMode True if the selection is in column mode. 410 */ 411 void setSelectionStart(const int column, const int line, const bool blockSelectionMode); 412 413 /** 414 * Sets the end of the current selection. 415 * 416 * \param column The column index of the last character in the selection. 417 * \param line The line index of the last character in the selection. 418 */ 419 void setSelectionEnd(const int column, const int line); 420 421 /** 422 * Retrieves the start of the selection or the cursor position if there 423 * is no selection. 424 */ 425 void getSelectionStart(int& column , int& line) const; 426 427 /** 428 * Retrieves the end of the selection or the cursor position if there 429 * is no selection. 430 */ 431 void getSelectionEnd(int& column , int& line) const; 432 433 /** Clears the current selection */ 434 void clearSelection(); 435 436 /** 437 * Returns true if the character at (@p column, @p line) is part of the 438 * current selection. 439 */ 440 bool isSelected(const int column,const int line) const; 441 442 /** 443 * Convenience method. Returns the currently selected text. 444 * \param preserveLineBreaks Specifies whether new line characters should 445 * be inserted into the returned text at the end of each terminal line. 446 */ 447 QString selectedText(bool preserveLineBreaks) const; 448 449 /** 450 * Copies part of the output to a stream. 451 * 452 * \param decoder A decoder which converts terminal characters into text 453 * \param fromLine The first line in the history to retrieve 454 * \param toLine The last line in the history to retrieve 455 */ 456 void writeLinesToStream(TerminalCharacterDecoder* decoder, int fromLine, int toLine) const; 457 458 /** 459 * Copies the selected characters, set using \see setSelBeginXY and \see setSelExtentXY 460 * into a stream. 461 * 462 * \param decoder A decoder which converts terminal characters into text. 463 * PlainTextDecoder is the most commonly used decoder which converts characters 464 * into plain text with no formatting. 465 * \param preserveLineBreaks Specifies whether new line characters should 466 * be inserted into the returned text at the end of each terminal line. 467 */ 468 void writeSelectionToStream(TerminalCharacterDecoder* decoder , bool 469 preserveLineBreaks = true) const; 470 471 /** 472 * Checks if the text between from and to is inside the current 473 * selection. If this is the case, the selection is cleared. The 474 * from and to are coordinates in the current viewable window. 475 * The loc(x,y) macro can be used to generate these values from a 476 * column,line pair. 477 * 478 * \param from The start of the area to check. 479 * \param to The end of the area to check 480 */ 481 void checkSelection(int from, int to); 482 483 /** 484 * Sets or clears an attribute of the current line. 485 * 486 * \param property The attribute to set or clear 487 * Possible properties are: 488 * LINE_WRAPPED: Specifies that the line is wrapped. 489 * LINE_DOUBLEWIDTH: Specifies that the characters in the current line 490 * should be double the normal width. 491 * LINE_DOUBLEHEIGHT:Specifies that the characters in the current line 492 * should be double the normal height. 493 * Double-height lines are formed of two lines containing the same characters, 494 * with both having the LINE_DOUBLEHEIGHT attribute. 495 * This allows other parts of the code to work on the 496 * assumption that all lines are the same height. 497 * 498 * \param enable true to apply the attribute to the current line or false to remove it 499 */ 500 void setLineProperty(LineProperty property , bool enable); 501 502 /** 503 * Returns the number of lines that the image has been scrolled up or down by, 504 * since the last call to resetScrolledLines(). 505 * 506 * a positive return value indicates that the image has been scrolled up, 507 * a negative return value indicates that the image has been scrolled down. 508 */ 509 int scrolledLines() const; 510 511 /** 512 * Returns the region of the image which was last scrolled. 513 * 514 * This is the area of the image from the top margin to the 515 * bottom margin when the last scroll occurred. 516 */ 517 QRect lastScrolledRegion() const; 518 519 /** 520 * Resets the count of the number of lines that the image has been scrolled up or down by, 521 * see scrolledLines() 522 */ 523 void resetScrolledLines(); 524 525 /** 526 * Returns the number of lines of output which have been 527 * dropped from the history since the last call 528 * to resetDroppedLines() 529 * 530 * If the history is not unlimited then it will drop 531 * the oldest lines of output if new lines are added when 532 * it is full. 533 */ 534 int droppedLines() const; 535 536 /** 537 * Resets the count of the number of lines dropped from 538 * the history. 539 */ 540 void resetDroppedLines(); 541 542 /** 543 * Fills the buffer @p dest with @p count instances of the default (ie. blank) 544 * Character style. 545 */ 546 static void fillWithDefaultChar(Character* dest, int count); 547 548 private: 549 550 //copies a line of text from the screen or history into a stream using a 551 //specified character decoder. Returns the number of lines actually copied, 552 //which may be less than 'count' if (start+count) is more than the number of characters on 553 //the line 554 // 555 //line - the line number to copy, from 0 (the earliest line in the history) up to 556 // history->getLines() + lines - 1 557 //start - the first column on the line to copy 558 //count - the number of characters on the line to copy 559 //decoder - a decoder which converts terminal characters (an Character array) into text 560 //appendNewLine - if true a new line character (\n) is appended to the end of the line 561 int copyLineToStream(int line, 562 int start, 563 int count, 564 TerminalCharacterDecoder* decoder, 565 bool appendNewLine, 566 bool preserveLineBreaks) const; 567 568 //fills a section of the screen image with the character 'c' 569 //the parameters are specified as offsets from the start of the screen image. 570 //the loc(x,y) macro can be used to generate these values from a column,line pair. 571 void clearImage(int loca, int loce, char c); 572 573 //move screen image between 'sourceBegin' and 'sourceEnd' to 'dest'. 574 //the parameters are specified as offsets from the start of the screen image. 575 //the loc(x,y) macro can be used to generate these values from a column,line pair. 576 // 577 //NOTE: moveImage() can only move whole lines 578 void moveImage(int dest, int sourceBegin, int sourceEnd); 579 // scroll up 'i' lines in current region, clearing the bottom 'i' lines 580 void scrollUp(int from, int i); 581 // scroll down 'i' lines in current region, clearing the top 'i' lines 582 void scrollDown(int from, int i); 583 584 void addHistLine(); 585 586 void initTabStops(); 587 588 void updateEffectiveRendition(); 589 void reverseRendition(Character& p) const; 590 591 bool isSelectionValid() const; 592 // copies text from 'startIndex' to 'endIndex' to a stream 593 // startIndex and endIndex are positions generated using the loc(x,y) macro 594 void writeToStream(TerminalCharacterDecoder* decoder, int startIndex, 595 int endIndex, bool preserveLineBreaks = true) const; 596 // copies 'count' lines from the screen buffer into 'dest', 597 // starting from 'startLine', where 0 is the first line in the screen buffer 598 void copyFromScreen(Character* dest, int startLine, int count) const; 599 // copies 'count' lines from the history buffer into 'dest', 600 // starting from 'startLine', where 0 is the first line in the history 601 void copyFromHistory(Character* dest, int startLine, int count) const; 602 603 604 // screen image ---------------- 605 int lines; 606 int columns; 607 608 typedef QVector<Character> ImageLine; // [0..columns] 609 ImageLine* screenLines; // [lines] 610 611 int _scrolledLines; 612 QRect _lastScrolledRegion; 613 614 int _droppedLines; 615 616 QVarLengthArray<LineProperty,64> lineProperties; 617 618 // history buffer --------------- 619 HistoryScroll* history; 620 621 // cursor location 622 int cuX; 623 int cuY; 624 625 // cursor color and rendition info 626 CharacterColor currentForeground; 627 CharacterColor currentBackground; 628 quint8 currentRendition; 629 630 // margins ---------------- 631 int _topMargin; 632 int _bottomMargin; 633 634 // states ---------------- 635 int currentModes[MODES_SCREEN]; 636 int savedModes[MODES_SCREEN]; 637 638 // ---------------------------- 639 640 QBitArray tabStops; 641 642 // selection ------------------- 643 int selBegin; // The first location selected. 644 int selTopLeft; // TopLeft Location. 645 int selBottomRight; // Bottom Right Location. 646 bool blockSelectionMode; // Column selection mode 647 648 // effective colors and rendition ------------ 649 CharacterColor effectiveForeground; // These are derived from 650 CharacterColor effectiveBackground; // the cu_* variables above 651 quint8 effectiveRendition; // to speed up operation 652 653 class SavedState 654 { 655 public: SavedState()656 SavedState() 657 : cursorColumn(0),cursorLine(0),rendition(0) {} 658 659 int cursorColumn; 660 int cursorLine; 661 quint8 rendition; 662 CharacterColor foreground; 663 CharacterColor background; 664 }; 665 SavedState savedState; 666 667 // last position where we added a character 668 int lastPos; 669 670 static Character defaultChar; 671 672 Screen (const Screen&) = delete; 673 Screen& operator= (const Screen&) = delete; 674 }; 675 676 } 677 678 #endif // SCREEN_H 679