| /* interestingtimes.c - cursor control |
| * |
| * Copyright 2015 Rob Landley <rob@landley.net> |
| */ |
| |
| #include "toys.h" |
| |
| int xgettty(void) |
| { |
| int i, j; |
| |
| for (i = 0; i<3; i++) if (isatty(j = (i+1)%3)) return j; |
| |
| return xopen("/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 (!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; |
| } |
| |
| // Reset terminal to known state, saving copy of old state if old != NULL. |
| int set_terminal(int fd, int raw, struct termios *old) |
| { |
| struct termios termio; |
| |
| // Fetch local copy of old terminfo, and copy struct contents to *old if set |
| if (!tcgetattr(fd, &termio) && 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); |
| |
| return tcsetattr(fd, TCSANOW, &termio); |
| } |
| |
| // Scan stdin for a keypress, parsing known escape sequences |
| // Returns: 0-255=literal, -1=EOF, -2=NONE, 256-...=index into seq |
| // 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 block) |
| { |
| // up down right left pgup pgdn home end ins |
| char *seqs[] = {"\033[A", "\033[B", "\033[C", "\033[D", "\033[5~", "\033[6~", |
| "\033OH", "\033OF", "\033[2~", 0}; |
| struct pollfd pfd; |
| int maybe, i, j; |
| char *test; |
| |
| for (;;) { |
| pfd.fd = 0; |
| pfd.events = POLLIN; |
| pfd.revents = 0; |
| |
| // check sequences |
| maybe = 0; |
| if (*scratch) { |
| for (i = maybe = 0; (test = seqs[i]); i++) { |
| 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 || !block) if (!xpoll(&pfd, 1, 30*maybe)) break; |
| |
| if (1 != read(0, scratch+1+*scratch, 1)) return -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(1, 0, 0); |
| tty_esc("?25h"); |
| tty_esc("0m"); |
| tty_jump(0, 999); |
| tty_esc("K"); |
| } |
| |
| void tty_sigreset(int i) |
| { |
| tty_reset(); |
| _exit(128+i); |
| } |