diff options
Diffstat (limited to 'lib/tty.c')
-rw-r--r-- | lib/tty.c | 277 |
1 files changed, 277 insertions, 0 deletions
diff --git a/lib/tty.c b/lib/tty.c new file mode 100644 index 00000000..a1aa2b67 --- /dev/null +++ b/lib/tty.c @@ -0,0 +1,277 @@ +/* interestingtimes.c - cursor control + * + * Copyright 2015 Rob Landley <rob@landley.net> + */ + +#include "toys.h" + +int tty_fd(void) +{ + int i, j; + + for (i = 0; i<3; i++) if (isatty(j = (i+1)%3)) return j; + + return notstdio(open("/dev/tty", O_RDWR)); +} + +// Quick and dirty query size of terminal, doesn't do ANSI probe fallback. +// set x=80 y=25 before calling to provide defaults. Returns 0 if couldn't +// determine size. + +int terminal_size(unsigned *xx, unsigned *yy) +{ + struct winsize ws; + unsigned i, x = 0, y = 0; + char *s; + + // stdin, stdout, stderr + for (i=0; i<3; i++) { + memset(&ws, 0, sizeof(ws)); + if (isatty(i) && !ioctl(i, TIOCGWINSZ, &ws)) { + if (ws.ws_col) x = ws.ws_col; + if (ws.ws_row) y = ws.ws_row; + + break; + } + } + s = getenv("COLUMNS"); + if (s) sscanf(s, "%u", &x); + s = getenv("LINES"); + if (s) sscanf(s, "%u", &y); + + // Never return 0 for either value, leave it at default instead. + if (xx && x) *xx = x; + if (yy && y) *yy = y; + + return x || y; +} + +// Query terminal size, sending ANSI probe if necesary. (Probe queries xterm +// size through serial connection, when local TTY doesn't know but remote does.) +// Returns 0 if ANSI probe sent, 1 if size determined from tty or environment + +int terminal_probesize(unsigned *xx, unsigned *yy) +{ + if (terminal_size(xx, yy) && (!xx || *xx) && (!yy || *yy)) return 1; + + // Send probe: bookmark cursor position, jump to bottom right, + // query position, return cursor to bookmarked position. + xprintf("\033[s\033[999C\033[999B\033[6n\033[u"); + + return 0; +} + +// Wrapper that parses results from ANSI probe to update screensize. +// Otherwise acts like scan_key() +int scan_key_getsize(char *scratch, int miliwait, unsigned *xx, unsigned *yy) +{ + int key; + + if (512&(key = scan_key(scratch, miliwait))) { + if (key>0) { + if (xx) *xx = (key>>10)&1023; + if (yy) *yy = (key>>20)&1023; + + return -3; + } + } + + return key; +} + +// Reset terminal to known state, saving copy of old state if old != NULL. +int set_terminal(int fd, int raw, int speed, struct termios *old) +{ + struct termios termio; + int i = tcgetattr(fd, &termio); + + // Fetch local copy of old terminfo, and copy struct contents to *old if set + if (i) return i; + if (old) *old = termio; + + // the following are the bits set for an xterm. Linux text mode TTYs by + // default add two additional bits that only matter for serial processing + // (turn serial line break into an interrupt, and XON/XOFF flow control) + + // Any key unblocks output, swap CR and NL on input + termio.c_iflag = IXANY|ICRNL|INLCR; + if (toys.which->flags & TOYFLAG_LOCALE) termio.c_iflag |= IUTF8; + + // Output appends CR to NL, does magic undocumented postprocessing + termio.c_oflag = ONLCR|OPOST; + + // Leave serial port speed alone + // termio.c_cflag = C_READ|CS8|EXTB; + + // Generate signals, input entire line at once, echo output + // erase, line kill, escape control characters with ^ + // erase line char at a time + // "extended" behavior: ctrl-V quotes next char, ctrl-R reprints unread chars, + // ctrl-W erases word + termio.c_lflag = ISIG|ICANON|ECHO|ECHOE|ECHOK|ECHOCTL|ECHOKE|IEXTEN; + + if (raw) cfmakeraw(&termio); + + if (speed) { + int i, speeds[] = {50, 75, 110, 134, 150, 200, 300, 600, 1200, 1800, 2400, + 4800, 9600, 19200, 38400, 57600, 115200, 230400, 460800, + 500000, 576000, 921600, 1000000, 1152000, 1500000, 2000000, + 2500000, 3000000, 3500000, 4000000}; + + // Find speed in table, adjust to constant + for (i = 0; i < ARRAY_LEN(speeds); i++) if (speeds[i] == speed) break; + if (i == ARRAY_LEN(speeds)) error_exit("unknown speed: %d", speed); + cfsetspeed(&termio, i+1+4081*(i>15)); + } + + return tcsetattr(fd, TCSAFLUSH, &termio); +} + +void xset_terminal(int fd, int raw, int speed, struct termios *old) +{ + if (-1 != set_terminal(fd, raw, speed, old)) return; + + sprintf(libbuf, "/proc/self/fd/%d", fd); + libbuf[readlink0(libbuf, libbuf, sizeof(libbuf))] = 0; + perror_exit("tcsetattr %s", libbuf); +} + +struct scan_key_list { + char *name, *seq; +} static const scan_key_list[] = TAGGED_ARRAY(KEY, + // up down right left pgup pgdn home end ins + {"UP", "\033[A"}, {"DOWN", "\033[B"}, {"RIGHT", "\033[C"}, {"LEFT", "\033[D"}, + {"PGUP", "\033[5~"}, {"PGDN", "\033[6~"}, {"HOME", "\033OH"}, + {"END", "\033OF"}, {"INSERT", "\033[2~"}, + + {"F1", "\033OP"}, {"F2", "\033OQ"}, {"F3", "\033OR"}, {"F4", "\033OS"}, + {"F5", "\033[15~"}, {"F6", "\033[17~"}, {"F7", "\033[18~"}, + {"F8", "\033[19~"}, {"F9", "\033[20~"}, + + {"SUP", "\033[1;2A"}, {"AUP", "\033[1;3A"}, {"CUP", "\033[1;5A"}, + {"SDOWN", "\033[1;2B"}, {"ADOWN", "\033[1;3B"}, {"CDOWN", "\033[1;5B"}, + {"SRIGHT", "\033[1;2C"}, {"ARIGHT", "\033[1;3C"}, {"CRIGHT", "\033[1;5C"}, + {"SLEFT", "\033[1;2D"}, {"ALEFT", "\033[1;3D"}, {"CLEFT", "\033[1;5D"}, + + {"SF1", "\033O1;2P"}, {"AF1", "\033O1;3P"}, {"CF1", "\033[1;5P"} +); + +// Scan stdin for a keypress, parsing known escape sequences +// Blocks for miliwait miliseconds, none 0, forever if -1 +// Returns: 0-255=literal, -1=EOF, -2=TIMEOUT, 256-...=index into scan_key_list +// >512 is x<<9+y<<21 +// scratch space is necessary because last char of !seq could start new seq +// Zero out first byte of scratch before first call to scan_key +// block=0 allows fetching multiple characters before updating display +int scan_key(char *scratch, int miliwait) +{ + struct pollfd pfd; + int maybe, i, j; + char *test; + + for (;;) { + pfd.fd = 0; + pfd.events = POLLIN; + pfd.revents = 0; + + maybe = 0; + if (*scratch) { + int pos[6]; + unsigned x, y; + + // Check for return from terminal size probe + memset(pos, 0, 6*sizeof(int)); + scratch[(1+*scratch)&15] = 0; + sscanf(scratch+1, "\033%n[%n%3u%n;%n%3u%nR%n", pos, pos+1, &y, + pos+2, pos+3, &x, pos+4, pos+5); + if (pos[5]) { + // Recognized X/Y position, consume and return + *scratch = 0; + return 512+(x<<10)+(y<<20); + } else for (i=0; i<6; i++) if (pos[i]==*scratch) maybe = 1; + + // Check sequences + for (i = 0; i<ARRAY_LEN(scan_key_list); i++) { + test = scan_key_list[i].seq; + for (j = 0; j<*scratch; j++) if (scratch[j+1] != test[j]) break; + if (j == *scratch) { + maybe = 1; + if (!test[j]) { + // We recognized current sequence: consume and return + *scratch = 0; + return 256+i; + } + } + } + + // If current data can't be a known sequence, return next raw char + if (!maybe) break; + } + + // Need more data to decide + + // 30 miliseconds is about the gap between characters at 300 baud + if (maybe || miliwait != -1) + if (!xpoll(&pfd, 1, maybe ? 30 : miliwait)) break; + + // Read 1 byte so we don't overshoot sequence match. (We can deviate + // and fail to match, but match consumes entire buffer.) + if (toys.signal>0 || 1 != read(0, scratch+1+*scratch, 1)) + return (toys.signal>0) ? -3 : -1; + ++*scratch; + } + + // Was not a sequence + if (!*scratch) return -2; + i = scratch[1]; + if (--*scratch) memmove(scratch+1, scratch+2, *scratch); + + return i; +} + +void tty_esc(char *s) +{ + printf("\033[%s", s); +} + +void tty_jump(int x, int y) +{ + char s[32]; + + sprintf(s, "%d;%dH", y+1, x+1); + tty_esc(s); +} + +void tty_reset(void) +{ + set_terminal(0, 0, 0, 0); + tty_esc("?25h"); + tty_esc("0m"); + tty_jump(0, 999); + tty_esc("K"); + fflush(0); +} + +// If you call set_terminal(), use sigatexit(tty_sigreset); +void tty_sigreset(int i) +{ + tty_reset(); + _exit(i ? 128+i : 0); +} + +void start_redraw(unsigned *width, unsigned *height) +{ + // If never signaled, do raw mode setup. + if (!toys.signal) { + *width = 80; + *height = 25; + set_terminal(0, 1, 0, 0); + sigatexit(tty_sigreset); + xsignal(SIGWINCH, generic_signal); + } + if (toys.signal != -1) { + toys.signal = -1; + terminal_probesize(width, height); + } + xprintf("\033[H\033[J"); +} |