1 /* ROTE - Our Own Terminal Emulation library
2 * Copyright (c) 2004 Bruno T. C. de Oliveira
10 This program is free software; you can redistribute it and/or
11 modify it under the terms of the GNU Lesser General Public
12 License (LGPL) as published by the Free Software Foundation.
14 Please refer to the COPYING file for more information.
16 This program is distributed in the hope that it will be useful,
17 but WITHOUT ANY WARRANTY; without even the implied warranty of
18 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
19 General Public License for more details.
21 You should have received a copy of the GNU Lesser General Public
22 License along with this program; if not, write to the Free Software
23 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
25 Copyright (c) 2004 Bruno T. C. de Oliveira
29 #ifndef btco_ROTE_rote_h
30 #define btco_ROTE_rote_h
33 #include <sys/types.h>
37 /* Color codes: 0 = black, 1 = red, 2 = green, 3 = yellow, 4 = blue,
38 * 5 = magenta, 6 = cyan, 7 = white.
40 * An 'attribute' as used in this library means an 8-bit value that conveys
41 * a foreground color code, a background color code, and the bold
42 * and blink bits. Each cell in the virtual terminal screen is associated
43 * with an attribute that specifies its appearance. The bits of an attribute,
44 * from most significant to least significant, are
46 * bit: 7 6 5 4 3 2 1 0
47 * content: S F F F H B B B
50 * | | | `----- 3-bit background color code (0 - 7)
51 * | | `--------- blink bit (if on, text is blinking)
52 * | `------------- 3-bit foreground color code (0 - 7)
53 * `----------------- bold bit
55 * It is however recommended that you use the provided macros rather
56 * than dealing with this format directly.
58 * Sometimes we will call the 'SFFF' nibble above the 'extended
59 * foreground color code', and the 'HBBB' nibble the 'extended background
60 * color code'. So the extended color codes are just the regular
61 * color codes except that they have an additional bit (the most significant
62 * bit) indicating bold/blink.
65 /* retrieve attribute fields */
66 #define ROTE_ATTR_BG(attr) ((attr) & 0x07)
67 #define ROTE_ATTR_FG(attr) (((attr) & 0x70) >> 4)
69 /* retrieve 'extended' color codes (see above for info) */
70 #define ROTE_ATTR_XBG(attr) ((attr) & 0x0F)
71 #define ROTE_ATTR_XFG(attr) (((attr) & 0xF0) >> 4)
73 /* set attribute fields. This requires attr to be an lvalue, and it will
74 * be evaluated more than once. Use with care. */
75 #define ROTE_ATTR_MOD_BG(attr, newbg) attr &= 0xF8, attr |= (newbg)
76 #define ROTE_ATTR_MOD_FG(attr, newfg) attr &= 0x8F, attr |= ((newfg) << 4)
77 #define ROTE_ATTR_MOD_XBG(attr, newxbg) attr &= 0xF0, attr |= (newxbg)
78 #define ROTE_ATTR_MOD_XFG(attr, newxfg) attr &= 0x0F, attr |= ((newxfg) << 4)
79 #define ROTE_ATTR_MOD_BOLD(attr, boldbit) \
80 attr &= 0x7F, attr |= (boldbit)?0x80:0x00
81 #define ROTE_ATTR_MOD_BLINK(attr, blinkbit) \
82 attr &= 0xF7, attr |= (blinkbit)?0x08:0x00
84 /* these return non-zero for 'yes', zero for 'no'. Don't rely on them being
85 * any more specific than that (e.g. being exactly 1 for 'yes' or whatever). */
86 #define ROTE_ATTR_BOLD(attr) ((attr) & 0x80)
87 #define ROTE_ATTR_BLINK(attr) ((attr) & 0x08)
89 /* Represents each of the text cells in the terminal screen */
90 typedef struct RoteCell_ {
91 unsigned char ch; /* >= 32, that is, control characters are not
92 * allowed to be on the virtual screen */
94 unsigned char attr; /* a color attribute, as described previously */
97 /* Declaration of opaque rote_Term_Private structure */
98 typedef struct RoteTermPrivate_ RoteTermPrivate;
100 /* Represents a virtual terminal. You may directly access the fields
101 * of this structure, but please pay close attention to the fields
102 * marked read-only or with special usage notes. */
103 typedef struct RoteTerm_ {
104 int rows, cols; /* terminal dimensions, READ-ONLY. You
105 * can't resize the terminal by changing
106 * this (a segfault is about all you will
109 RoteCell **cells; /* matrix of cells. This
110 * matrix is indexed as cell[row][column]
111 * where 0 <= row < rows and
114 * You may freely modify the contents of
118 int crow, ccol; /* cursor coordinates. READ-ONLY. */
120 unsigned char curattr; /* current attribute, that is the attribute
121 * that will be used for newly inserted
124 pid_t childpid; /* pid of the child process running in the
125 * terminal; 0 for none. This is READ-ONLY. */
127 RoteTermPrivate *pd; /* private state data */
129 /* --- dirtiness flags: the following flags will be raised when the
130 * corresponding items are modified. They can only be unset by YOU
131 * (when, for example, you redraw the term or something) --- */
132 bool curpos_dirty; /* whether cursor location has changed */
133 bool *line_dirty; /* whether each row is dirty */
134 /* --- end dirtiness flags */
137 /* Creates a new virtual terminal with the given dimensions. You
138 * must destroy it with rote_vt_destroy after you are done with it.
139 * The terminal will be initially blank and the cursor will
140 * be at the top-left corner.
142 * Returns NULL on error.
144 RoteTerm *rote_vt_create(int rows, int cols);
146 /* Destroys a virtual terminal previously created with
147 * rote_vt_create. If rt == NULL, does nothing. */
148 void rote_vt_destroy(RoteTerm *rt);
150 /* Starts a forked process in the terminal. The <command> parameter
151 * is a shell command to execute (it will be interpreted by '/bin/sh -c')
152 * Returns the pid of the forked process.
154 * Some useful reminders: If you want to be notified when child processes exit,
155 * you should handle the SIGCHLD signal. If, on the other hand, you want to
156 * ignore exitting child processes, you should set the SIGCHLD handler to
157 * SIG_IGN to prevent child processes from hanging around the system as 'zombie
160 * Continuing to write to a RoteTerm whose child process has died does not
161 * accomplish a lot, but is not an error and should not cause your program
162 * to crash or block indefinitely or anything of that sort :-)
163 * If, however, you want to be tidy and inform the RoteTerm that its
164 * child has died, call rote_vt_forsake_child when appropriate.
166 * If there is an error, returns -1. Notice that passing an invalid
167 * command will not cause an error at this level: the shell will try
168 * to execute the command and will exit with status 127. You can catch
169 * that by installing a SIGCHLD handler if you want.
171 pid_t rote_vt_forkpty(RoteTerm *rt, const char *command);
173 /* Disconnects the RoteTerm from its forked child process. This function
174 * should be called when the child process dies or something of the sort.
175 * It is not strictly necessary to call this function, but it is
177 void rote_vt_forsake_child(RoteTerm *rt);
179 /* Does some data plumbing, that is, sees if the sub process has
180 * something to write to the terminal, and if so, write it. If you
181 * called rote_vt_fork to start a forked process, you must call
182 * this function regularly to update the terminal.
184 * This function will not block, that is, if there is no data to be
185 * read from the child process it will return immediately. */
186 void rote_vt_update(RoteTerm *rt);
188 /* Puts data into the terminal: if there is a forked process running,
189 * the data will be sent to it. If there is no forked process,
190 * the data will simply be injected into the terminal (as in
192 void rote_vt_write(RoteTerm *rt, const char *data, int length);
194 /* Inject data into the terminal. <data> needs NOT be 0-terminated:
195 * its length is solely determined by the <length> parameter. Please
196 * notice that this writes directly to the terminal, that is,
197 * this function does NOT send the data to the forked process
198 * running in the terminal (if any). For that, you might want
199 * to use rote_vt_write.
201 void rote_vt_inject(RoteTerm *rt, const char *data, int length);
203 /* Paints the virtual terminal screen on the given window, putting
204 * the top-left corner at the given position. The cur_set_attr
205 * function must set the curses attributes given a Rote attribute
206 * byte. It should, for example, do wattrset(win, COLOR_PAIR(n)) where
207 * n is the colorpair appropriate for the attribute and such.
209 * If you pass NULL for cur_set_attr, the default implementation will
210 * set the color pair given by (bg * 8 + 7 - fg), which seems to be
211 * a common mapping, and the bold and blink attributes will be mapped
212 * to A_BOLD and A_BLINK.
214 * At the end of the function, the cursor will be left where the virtual
215 * cursor of the terminal is supposed to be.
217 * This function does not call wrefresh(win); you have to do that yourself.
218 * This function automatically calls rote_vt_update prior to drawing
219 * so that the drawn contents are accurate.
221 void rote_vt_draw(RoteTerm *rt, WINDOW *win, int startrow, int startcol,
222 void (*cur_set_attr)(WINDOW *win, unsigned char attr));
224 /* Indicates to the terminal that the given key has been pressed.
225 * This will cause the terminal to rote_vt_write() the appropriate
226 * escape sequence for that key (that is, the escape sequence
227 * that the linux text-mode console would produce for it). The argument,
228 * keycode, must be a CURSES EXTENDED KEYCODE, the ones you get
229 * when you use keypad(somewin, TRUE) (see man page). */
230 void rote_vt_keypress(RoteTerm *rt, int keycode);
232 /* Takes a snapshot of the current contents of the terminal and
233 * saves them to a dynamically allocated buffer. Returns a pointer
234 * to the newly created buffer, which you can pass to
235 * rote_vt_restore_snapshot. Caller is responsible for free()'ing when
236 * the snapshot is no longer needed. */
237 void *rote_vt_take_snapshot(RoteTerm *rt);
239 /* Restores a snapshot previously taken with rote_vt_take_snapshot.
240 * This function does NOT free() the passed buffer */
241 void rote_vt_restore_snapshot(RoteTerm *rt, void *snapbuf);
243 /* Returns the pseudo tty descriptor associated with the given terminal.
244 * Please don't do weird things with it (like close it for instance),
245 * or things will break
247 * This function returns -1 if the given terminal does not yet have
248 * an associated pty. A pty is only associated to a terminal when
249 * needed, e.g. on a call to rote_vt_forkpty. */
250 int rote_vt_get_pty_fd(RoteTerm *rt);
252 /* Declaration of custom escape sequence callback type. See the
253 * rote_vt_add_es_handler function for more info */
254 typedef int (*rote_es_handler_t)(RoteTerm *rt, const char *es);
256 /* Installs a custom escape sequence handler for the given RoteTerm.
257 * The handler will be called by the library every time it tries to
258 * recognize an escape sequence; depending on the return value of the
259 * handler, it will proceed in a different manner. See the description
260 * of the possible return values (ROTE_HANDLERESULT_* constants) below
263 * This handler will be called EACH TIME THE ESCAPE SEQUENCE BUFFER
264 * RECEIVES A CHARACTER. Therefore, it must execute speedily in order
265 * not to create too heavy a performance penalty. In particular, the
266 * writer of the handler should take care to quickly test for invalid
267 * or incomplete escape sequences before trying to do more elaborate
270 * The handler will NOT be called with an empty escape sequence (i.e.
271 * one in which only the initial ESC was received).
273 * The custom handler receives the terminal it pertains to and the
274 * escape sequence as a string (without the initial escape character).
276 * The handler may of course modify the terminal as it sees fit, taking
277 * care not to corrupt it of course (in particular, it should appropriately
278 * raise the line_dirty[] and curpos_dirty flags to indicate what it has
281 void rote_vt_install_handler(RoteTerm *rt, rote_es_handler_t handler);
283 /* Possible return values for the custom handler function and their
285 #define ROTE_HANDLERESULT_OK 0 /* means escape sequence was handled */
287 #define ROTE_HANDLERESULT_NOTYET 1 /* means the escape sequence was not
288 * recognized yet, but there is hope that
289 * it still will once more characters
290 * arrive (i.e. it is not yet complete).
292 * The library will thus continue collecting
293 * characters and calling the handler as
294 * each character arrives until
295 * either OK or NOWAY is returned.
298 #define ROTE_HANDLERESULT_NOWAY 2 /* means the escape sequence was not
299 * recognized, and there is no chance
300 * that it will even if more characters
301 * are added to it. */