1 /* interestingtimes.c - cursor control
2 *
3 * Copyright 2015 Rob Landley <rob@landley.net>
4 */
5
6 #include "toys.h"
7
tty_fd(void)8 int tty_fd(void)
9 {
10 int i, j;
11
12 for (i = 0; i<3; i++) if (isatty(j = (i+1)%3)) return j;
13
14 return notstdio(open("/dev/tty", O_RDWR));
15 }
16
17 // Quick and dirty query size of terminal, doesn't do ANSI probe fallback.
18 // set x=80 y=25 before calling to provide defaults. Returns 0 if couldn't
19 // determine size.
20
terminal_size(unsigned * xx,unsigned * yy)21 int terminal_size(unsigned *xx, unsigned *yy)
22 {
23 struct winsize ws;
24 unsigned i, x = 0, y = 0;
25 char *s;
26
27 // stdin, stdout, stderr
28 for (i=0; i<3; i++) {
29 memset(&ws, 0, sizeof(ws));
30 if (isatty(i) && !ioctl(i, TIOCGWINSZ, &ws)) {
31 if (ws.ws_col) x = ws.ws_col;
32 if (ws.ws_row) y = ws.ws_row;
33
34 break;
35 }
36 }
37 s = getenv("COLUMNS");
38 if (s) sscanf(s, "%u", &x);
39 s = getenv("LINES");
40 if (s) sscanf(s, "%u", &y);
41
42 // Never return 0 for either value, leave it at default instead.
43 if (xx && x) *xx = x;
44 if (yy && y) *yy = y;
45
46 return x || y;
47 }
48
49 // Query terminal size, sending ANSI probe if necesary. (Probe queries xterm
50 // size through serial connection, when local TTY doesn't know but remote does.)
51 // Returns 0 if ANSI probe sent, 1 if size determined from tty or environment
52
terminal_probesize(unsigned * xx,unsigned * yy)53 int terminal_probesize(unsigned *xx, unsigned *yy)
54 {
55 if (terminal_size(xx, yy) && (!xx || *xx) && (!yy || *yy)) return 1;
56
57 // Send probe: bookmark cursor position, jump to bottom right,
58 // query position, return cursor to bookmarked position.
59 xprintf("\033[s\033[999C\033[999B\033[6n\033[u");
60
61 return 0;
62 }
63
64 // Reset terminal to known state, saving copy of old state if old != NULL.
set_terminal(int fd,int raw,int speed,struct termios * old)65 int set_terminal(int fd, int raw, int speed, struct termios *old)
66 {
67 struct termios termio;
68 int i = tcgetattr(fd, &termio);
69
70 // Fetch local copy of old terminfo, and copy struct contents to *old if set
71 if (i) return i;
72 if (old) *old = termio;
73
74 // the following are the bits set for an xterm. Linux text mode TTYs by
75 // default add two additional bits that only matter for serial processing
76 // (turn serial line break into an interrupt, and XON/XOFF flow control)
77
78 // Any key unblocks output, swap CR and NL on input
79 termio.c_iflag = IXANY|ICRNL|INLCR;
80 if (toys.which->flags & TOYFLAG_LOCALE) termio.c_iflag |= IUTF8;
81
82 // Output appends CR to NL, does magic undocumented postprocessing
83 termio.c_oflag = ONLCR|OPOST;
84
85 // Leave serial port speed alone
86 // termio.c_cflag = C_READ|CS8|EXTB;
87
88 // Generate signals, input entire line at once, echo output
89 // erase, line kill, escape control characters with ^
90 // erase line char at a time
91 // "extended" behavior: ctrl-V quotes next char, ctrl-R reprints unread chars,
92 // ctrl-W erases word
93 termio.c_lflag = ISIG|ICANON|ECHO|ECHOE|ECHOK|ECHOCTL|ECHOKE|IEXTEN;
94
95 if (raw) cfmakeraw(&termio);
96
97 if (speed) {
98 int i, speeds[] = {50, 75, 110, 134, 150, 200, 300, 600, 1200, 1800, 2400,
99 4800, 9600, 19200, 38400, 57600, 115200, 230400, 460800,
100 500000, 576000, 921600, 1000000, 1152000, 1500000, 2000000,
101 2500000, 3000000, 3500000, 4000000};
102
103 // Find speed in table, adjust to constant
104 for (i = 0; i < ARRAY_LEN(speeds); i++) if (speeds[i] == speed) break;
105 if (i == ARRAY_LEN(speeds)) error_exit("unknown speed: %d", speed);
106 cfsetspeed(&termio, i+1+4081*(i>15));
107 }
108
109 return tcsetattr(fd, TCSAFLUSH, &termio);
110 }
111
xset_terminal(int fd,int raw,int speed,struct termios * old)112 void xset_terminal(int fd, int raw, int speed, struct termios *old)
113 {
114 if (-1 != set_terminal(fd, raw, speed, old)) return;
115
116 sprintf(libbuf, "/proc/self/fd/%d", fd);
117 libbuf[readlink0(libbuf, libbuf, sizeof(libbuf))] = 0;
118 perror_exit("tcsetattr %s", libbuf);
119 }
120
121 struct scan_key_list {
122 int key;
123 char *seq;
124 } static const scan_key_list[] = {
125 {KEY_UP, "\033[A"}, {KEY_DOWN, "\033[B"},
126 {KEY_RIGHT, "\033[C"}, {KEY_LEFT, "\033[D"},
127
128 {KEY_UP|KEY_SHIFT, "\033[1;2A"}, {KEY_DOWN|KEY_SHIFT, "\033[1;2B"},
129 {KEY_RIGHT|KEY_SHIFT, "\033[1;2C"}, {KEY_LEFT|KEY_SHIFT, "\033[1;2D"},
130
131 {KEY_UP|KEY_ALT, "\033[1;3A"}, {KEY_DOWN|KEY_ALT, "\033[1;3B"},
132 {KEY_RIGHT|KEY_ALT, "\033[1;3C"}, {KEY_LEFT|KEY_ALT, "\033[1;3D"},
133
134 {KEY_UP|KEY_CTRL, "\033[1;5A"}, {KEY_DOWN|KEY_CTRL, "\033[1;5B"},
135 {KEY_RIGHT|KEY_CTRL, "\033[1;5C"}, {KEY_LEFT|KEY_CTRL, "\033[1;5D"},
136
137 // VT102/VT220 escapes.
138 {KEY_HOME, "\033[1~"},
139 {KEY_INSERT, "\033[2~"},
140 {KEY_DELETE, "\033[3~"},
141 {KEY_END, "\033[4~"},
142 {KEY_PGUP, "\033[5~"},
143 {KEY_PGDN, "\033[6~"},
144 // "Normal" "PC" escapes (xterm).
145 {KEY_HOME, "\033OH"},
146 {KEY_END, "\033OF"},
147 // "Application" "PC" escapes (gnome-terminal).
148 {KEY_HOME, "\033[H"},
149 {KEY_END, "\033[F"},
150
151 {KEY_FN+1, "\033OP"}, {KEY_FN+2, "\033OQ"}, {KEY_FN+3, "\033OR"},
152 {KEY_FN+4, "\033OS"}, {KEY_FN+5, "\033[15~"}, {KEY_FN+6, "\033[17~"},
153 {KEY_FN+7, "\033[18~"}, {KEY_FN+8, "\033[19~"}, {KEY_FN+9, "\033[20~"},
154 };
155
156 // Scan stdin for a keypress, parsing known escape sequences, including
157 // responses to screen size queries.
158 // Blocks for timeout_ms milliseconds, 0=return immediately, -1=wait forever.
159 // Returns 0-255=literal, -1=EOF, -2=TIMEOUT, -3=RESIZE, 256+= a KEY_ constant.
160 // Scratch space is necessary because last char of !seq could start new seq.
161 // Zero out first byte of scratch before first call to scan_key.
scan_key_getsize(char * scratch,int timeout_ms,unsigned * xx,unsigned * yy)162 int scan_key_getsize(char *scratch, int timeout_ms, unsigned *xx, unsigned *yy)
163 {
164 struct pollfd pfd;
165 int maybe, i, j;
166 char *test;
167
168 for (;;) {
169 pfd.fd = 0;
170 pfd.events = POLLIN;
171 pfd.revents = 0;
172
173 maybe = 0;
174 if (*scratch) {
175 int pos[6];
176 unsigned x, y;
177
178 // Check for return from terminal size probe
179 memset(pos, 0, 6*sizeof(int));
180 scratch[(1+*scratch)&15] = 0;
181 sscanf(scratch+1, "\033%n[%n%3u%n;%n%3u%nR%n", pos, pos+1, &y,
182 pos+2, pos+3, &x, pos+4, pos+5);
183 if (pos[5]) {
184 // Recognized X/Y position, consume and return
185 *scratch = 0;
186 if (xx) *xx = x;
187 if (yy) *yy = y;
188 return -3;
189 } else for (i=0; i<6; i++) if (pos[i]==*scratch) maybe = 1;
190
191 // Check sequences
192 for (i = 0; i<ARRAY_LEN(scan_key_list); i++) {
193 test = scan_key_list[i].seq;
194 for (j = 0; j<*scratch; j++) if (scratch[j+1] != test[j]) break;
195 if (j == *scratch) {
196 maybe = 1;
197 if (!test[j]) {
198 // We recognized current sequence: consume and return
199 *scratch = 0;
200 return 256+scan_key_list[i].key;
201 }
202 }
203 }
204
205 // If current data can't be a known sequence, return next raw char
206 if (!maybe) break;
207 }
208
209 // Need more data to decide
210
211 // 30ms is about the gap between characters at 300 baud
212 if (maybe || timeout_ms != -1)
213 if (!xpoll(&pfd, 1, maybe ? 30 : timeout_ms)) break;
214
215 // Read 1 byte so we don't overshoot sequence match. (We can deviate
216 // and fail to match, but match consumes entire buffer.)
217 if (toys.signal>0 || 1 != read(0, scratch+1+*scratch, 1))
218 return (toys.signal>0) ? -3 : -1;
219 ++*scratch;
220 }
221
222 // Was not a sequence
223 if (!*scratch) return -2;
224 i = scratch[1];
225 if (--*scratch) memmove(scratch+1, scratch+2, *scratch);
226
227 return i;
228 }
229
230 // Wrapper that ignores results from ANSI probe to update screensize.
231 // Otherwise acts like scan_key_getsize().
scan_key(char * scratch,int timeout_ms)232 int scan_key(char *scratch, int timeout_ms)
233 {
234 return scan_key_getsize(scratch, timeout_ms, NULL, NULL);
235 }
236
tty_esc(char * s)237 void tty_esc(char *s)
238 {
239 printf("\033[%s", s);
240 }
241
tty_jump(int x,int y)242 void tty_jump(int x, int y)
243 {
244 char s[32];
245
246 sprintf(s, "%d;%dH", y+1, x+1);
247 tty_esc(s);
248 }
249
tty_reset(void)250 void tty_reset(void)
251 {
252 set_terminal(0, 0, 0, 0);
253 tty_esc("?25h");
254 tty_esc("0m");
255 tty_jump(0, 999);
256 tty_esc("K");
257 fflush(0);
258 }
259
260 // If you call set_terminal(), use sigatexit(tty_sigreset);
tty_sigreset(int i)261 void tty_sigreset(int i)
262 {
263 tty_reset();
264 _exit(i ? 128+i : 0);
265 }
266
start_redraw(unsigned * width,unsigned * height)267 void start_redraw(unsigned *width, unsigned *height)
268 {
269 // If never signaled, do raw mode setup.
270 if (!toys.signal) {
271 *width = 80;
272 *height = 25;
273 set_terminal(0, 1, 0, 0);
274 sigatexit(tty_sigreset);
275 xsignal(SIGWINCH, generic_signal);
276 }
277 if (toys.signal != -1) {
278 toys.signal = -1;
279 terminal_probesize(width, height);
280 }
281 xprintf("\033[H\033[J");
282 }
283