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Diffstat (limited to 'src/vt52_curses.hh')
| -rw-r--r-- | src/vt52_curses.hh | 154 |
1 files changed, 154 insertions, 0 deletions
diff --git a/src/vt52_curses.hh b/src/vt52_curses.hh new file mode 100644 index 0000000..88c3cb3 --- /dev/null +++ b/src/vt52_curses.hh @@ -0,0 +1,154 @@ +/** + * Copyright (c) 2007-2012, Timothy Stack + * + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * + * * Redistributions of source code must retain the above copyright notice, this + * list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above copyright notice, + * this list of conditions and the following disclaimer in the documentation + * and/or other materials provided with the distribution. + * * Neither the name of Timothy Stack nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ''AS IS'' AND ANY + * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED + * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE + * DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY + * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES + * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; + * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND + * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS + * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * @file vt52_curses.hh + */ + +#ifndef vt52_curses_hh +#define vt52_curses_hh + +#include <list> +#include <string> + +#include "view_curses.hh" + +/** + * VT52 emulator for curses, useful for mediating between curses and readline, + * which don't play well together. It is expected that a subclass of this + * class will fork off a child process that sends and receives VT52 keycodes(?) + * which is translated by this class into curses calls. + * + * VT52 seems to be the simplest terminal to emulate since we do not need to + * maintain the state of the screen, beyond past lines. For example, when + * inserting a character, VT52 moves the cursor to the insertion point, clears + * the rest of the line and then rewrites the rest of the line with the new + * character. This is in contrast to VT100 which moves the cursor to the + * insertion point and then sends a code to insert the character and relying + * on the terminal to shift the rest of the line to the right a character. + */ +class vt52_curses : public view_curses { +public: + /** @param win The curses window this view is attached to. */ + void set_window(WINDOW* win) { this->vc_window = win; } + + /** @return The curses window this view is attached to. */ + WINDOW* get_window() { return this->vc_window; } + + void set_left(int left) { this->vc_left = left; } + + int get_left() const { return this->vc_left; } + + /** + * Set the Y position of this view on the display. A value greater than + * zero is considered to be an absolute size. A value less than zero makes + * the position relative to the bottom of the enclosing window. + * + * @param y The Y position of the cursor on the curses display. + */ + void set_y(int y) { this->vc_y = y; } + + /** @return The abs/rel Y position of the cursor on the curses display. */ + int get_y() const { return this->vc_y; } + + /** @param x The X position of the cursor on the curses display. */ + void set_x(int x) { this->vc_x = x; } + + /** @return The X position of the cursor on the curses display. */ + int get_x() const { return this->vc_x; } + + /** + * @return The height of this view, which consists of a single line for + * input, plus any past lines of output, which will appear ABOVE the Y + * position for this view. + * @todo Kinda hardwired to the way readline works. + */ + int get_height() { return 1; } + + void set_max_height(int mh) { this->vc_max_height = mh; } + int get_max_height() const { return this->vc_max_height; } + + /** + * Map an ncurses input keycode to a vt52 sequence. + * + * @param ch The input character. + * @param len_out The length of the returned sequence. + * @return The vt52 sequence to send to the child. + */ + const char* map_input(int ch, int& len_out); + + /** + * Map VT52 output to ncurses calls. + * + * @param output VT52 encoded output from the child process. + * @param len The length of the output array. + */ + void map_output(const char* output, int len); + + /** + * Paints any past lines and moves the cursor to the current X position. + */ + void do_update(); + + const static char ESCAPE = 27; /*< VT52 Escape key value. */ + const static char BACKSPACE = 8; /*< VT52 Backspace key value. */ + const static char BELL = 7; /*< VT52 Bell value. */ + const static char STX = 2; /*< VT52 Start-of-text value. */ + +protected: + /** @return The absolute Y position of this view. */ + int get_actual_y() + { + unsigned long width, height; + int retval; + + getmaxyx(this->vc_window, height, width); + if (this->vc_y < 0) { + retval = height + this->vc_y; + } else { + retval = this->vc_y; + } + + return retval; + } + + WINDOW* vc_window{nullptr}; /*< The window that contains this view. */ + int vc_left{0}; + int vc_x{0}; /*< The X position of the cursor. */ + int vc_y{0}; /*< The Y position of the cursor. */ + int vc_max_height{0}; + char vc_escape[16]; /*< Storage for escape sequences. */ + int vc_escape_len{0}; /*< The number of chars in vc_escape. */ + int vc_expected_escape_len{-1}; + char vc_map_buffer{0}; /*< + * Buffer returned by map_input for trivial + * translations (one-to-one). + */ + attr_line_t vc_line; +}; + +#endif |