1 /* interestingtimes.c - cursor control
3 * Copyright 2015 Rob Landley <rob@landley.net>
12 for (i = 0; i<3; i++) if (isatty(j = (i+1)%3)) return j;
14 return xopen("/dev/tty", O_RDWR);
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
21 int terminal_size(unsigned *xx, unsigned *yy)
24 unsigned i, x = 0, y = 0;
27 // stdin, stdout, stderr
29 memset(&ws, 0, sizeof(ws));
30 if (!ioctl(i, TIOCGWINSZ, &ws)) {
31 if (ws.ws_col) x = ws.ws_col;
32 if (ws.ws_row) y = ws.ws_row;
37 s = getenv("COLUMNS");
38 if (s) sscanf(s, "%u", &x);
40 if (s) sscanf(s, "%u", &y);
42 // Never return 0 for either value, leave it at default instead.
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
53 int terminal_probesize(unsigned *xx, unsigned *yy)
55 if (terminal_size(xx, yy) && (!xx || *xx) && (!yy || *yy)) return 1;
57 // Send probe: bookmark cursor position, jump to bottom right,
58 // query position, return cursor to bookmarked position.
59 xprintf("\e[s\e[999C\e[999B\e[6n\e[u");
64 // Wrapper that parses results from ANSI probe to update screensize.
65 // Otherwise acts like scan_key()
66 int scan_key_getsize(char *scratch, int miliwait, unsigned *xx, unsigned *yy)
70 if (512&(key = scan_key(scratch, miliwait))) {
72 if (xx) *xx = (key>>10)&1023;
73 if (yy) *yy = (key>>20)&1023;
74 toys.signal = SIGWINCH;
83 // Reset terminal to known state, saving copy of old state if old != NULL.
84 int set_terminal(int fd, int raw, struct termios *old)
86 struct termios termio;
88 // Fetch local copy of old terminfo, and copy struct contents to *old if set
89 if (!tcgetattr(fd, &termio) && old) *old = termio;
91 // the following are the bits set for an xterm. Linux text mode TTYs by
92 // default add two additional bits that only matter for serial processing
93 // (turn serial line break into an interrupt, and XON/XOFF flow control)
95 // Any key unblocks output, swap CR and NL on input
96 termio.c_iflag = IXANY|ICRNL|INLCR;
97 if (toys.which->flags & TOYFLAG_LOCALE) termio.c_iflag |= IUTF8;
99 // Output appends CR to NL, does magic undocumented postprocessing
100 termio.c_oflag = ONLCR|OPOST;
102 // Leave serial port speed alone
103 // termio.c_cflag = C_READ|CS8|EXTB;
105 // Generate signals, input entire line at once, echo output
106 // erase, line kill, escape control characters with ^
107 // erase line char at a time
108 // "extended" behavior: ctrl-V quotes next char, ctrl-R reprints unread chars,
109 // ctrl-W erases word
110 termio.c_lflag = ISIG|ICANON|ECHO|ECHOE|ECHOK|ECHOCTL|ECHOKE|IEXTEN;
112 if (raw) cfmakeraw(&termio);
114 return tcsetattr(fd, TCSANOW, &termio);
117 void xset_terminal(int fd, int raw, struct termios *old)
119 if (-1 == set_terminal(fd, raw, old)) perror_exit("bad tty fd#%d", fd);
122 struct scan_key_list {
124 } static const scan_key_list[] = TAGGED_ARRAY(KEY,
125 // up down right left pgup pgdn home end ins
126 {"UP", "\033[A"}, {"DOWN", "\033[B"}, {"RIGHT", "\033[C"}, {"LEFT", "\033[D"},
127 {"PGUP", "\033[5~"}, {"PGDN", "\033[6~"}, {"HOME", "\033OH"},
128 {"END", "\033OF"}, {"INSERT", "\033[2~"},
130 {"F1", "\033OP"}, {"F2", "\033OQ"}, {"F3", "\033OR"}, {"F4", "\033OS"},
131 {"F5", "\033[15~"}, {"F6", "\033[17~"}, {"F7", "\033[18~"},
132 {"F8", "\033[19~"}, {"F9", "\033[20~"},
134 {"SUP", "\033[1;2A"}, {"AUP", "\033[1;3A"}, {"CUP", "\033[1;5A"},
135 {"SDOWN", "\033[1;2B"}, {"ADOWN", "\033[1;3B"}, {"CDOWN", "\033[1;5B"},
136 {"SRIGHT", "\033[1;2C"}, {"ARIGHT", "\033[1;3C"}, {"CRIGHT", "\033[1;5C"},
137 {"SLEFT", "\033[1;2D"}, {"ALEFT", "\033[1;3D"}, {"CLEFT", "\033[1;5D"},
139 {"SF1", "\033O1;2P"}, {"AF1", "\033O1;3P"}, {"CF1", "\033[1;5P"}
142 // Scan stdin for a keypress, parsing known escape sequences
143 // Blocks for miliwait miliseconds, none 0, forever if -1
144 // Returns: 0-255=literal, -1=EOF, -2=NONE, 256-...=index into scan_key_list
145 // >512 is x<<9+y<<21
146 // scratch space is necessary because last char of !seq could start new seq
147 // Zero out first byte of scratch before first call to scan_key
148 // block=0 allows fetching multiple characters before updating display
149 int scan_key(char *scratch, int miliwait)
165 // Check for return from terminal size probe
166 memset(pos, 0, 6*sizeof(int));
167 scratch[(1+*scratch)&15] = 0;
168 sscanf(scratch+1, "\033%n[%n%3u%n;%n%3u%nR%n", pos, pos+1, &y,
169 pos+2, pos+3, &x, pos+4, pos+5);
171 // Recognized X/Y position, consume and return
173 return 512+(x<<10)+(y<<20);
174 } else for (i=0; i<6; i++) if (pos[i]==*scratch) maybe = 1;
177 for (i = 0; i<ARRAY_LEN(scan_key_list); i++) {
178 test = scan_key_list[i].seq;
179 for (j = 0; j<*scratch; j++) if (scratch[j+1] != test[j]) break;
183 // We recognized current sequence: consume and return
190 // If current data can't be a known sequence, return next raw char
194 // Need more data to decide
196 // 30 miliseconds is about the gap between characters at 300 baud
197 if (maybe || miliwait != -1)
198 if (!xpoll(&pfd, 1, maybe ? 30 : miliwait)) break;
200 // Read 1 byte so we don't overshoot sequence match. (We can deviate
201 // and fail to match, but match consumes entire buffer.)
202 if (toys.signal || 1 != read(0, scratch+1+*scratch, 1))
203 return toys.signal ? -3 : -1;
207 // Was not a sequence
208 if (!*scratch) return -2;
210 if (--*scratch) memmove(scratch+1, scratch+2, *scratch);
215 void tty_esc(char *s)
217 printf("\033[%s", s);
220 void tty_jump(int x, int y)
224 sprintf(s, "%d;%dH", y+1, x+1);
230 set_terminal(0, 0, 0);
238 // If you call set_terminal(), use sigatexit(tty_sigreset);
239 void tty_sigreset(int i)
242 _exit(i ? 128+i : 0);