1 /* interestingtimes.c - cursor control 2 * 3 * Copyright 2015 Rob Landley <rob (at) landley.net> 4 */ 5 6 #include "toys.h" 7 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 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 (!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 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("\e[s\e[999C\e[999B\e[6n\e[u"); 60 61 return 0; 62 } 63 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) 67 { 68 int key; 69 70 if (512&(key = scan_key(scratch, miliwait))) { 71 if (key>0) { 72 if (xx) *xx = (key>>10)&1023; 73 if (yy) *yy = (key>>20)&1023; 74 75 return -3; 76 } 77 } 78 79 return key; 80 } 81 82 // Reset terminal to known state, saving copy of old state if old != NULL. 83 int set_terminal(int fd, int raw, struct termios *old) 84 { 85 struct termios termio; 86 87 // Fetch local copy of old terminfo, and copy struct contents to *old if set 88 if (!tcgetattr(fd, &termio) && old) *old = termio; 89 90 // the following are the bits set for an xterm. Linux text mode TTYs by 91 // default add two additional bits that only matter for serial processing 92 // (turn serial line break into an interrupt, and XON/XOFF flow control) 93 94 // Any key unblocks output, swap CR and NL on input 95 termio.c_iflag = IXANY|ICRNL|INLCR; 96 if (toys.which->flags & TOYFLAG_LOCALE) termio.c_iflag |= IUTF8; 97 98 // Output appends CR to NL, does magic undocumented postprocessing 99 termio.c_oflag = ONLCR|OPOST; 100 101 // Leave serial port speed alone 102 // termio.c_cflag = C_READ|CS8|EXTB; 103 104 // Generate signals, input entire line at once, echo output 105 // erase, line kill, escape control characters with ^ 106 // erase line char at a time 107 // "extended" behavior: ctrl-V quotes next char, ctrl-R reprints unread chars, 108 // ctrl-W erases word 109 termio.c_lflag = ISIG|ICANON|ECHO|ECHOE|ECHOK|ECHOCTL|ECHOKE|IEXTEN; 110 111 if (raw) cfmakeraw(&termio); 112 113 return tcsetattr(fd, TCSANOW, &termio); 114 } 115 116 void xset_terminal(int fd, int raw, struct termios *old) 117 { 118 if (-1 == set_terminal(fd, raw, old)) perror_exit("bad tty fd#%d", fd); 119 } 120 121 struct scan_key_list { 122 char *name, *seq; 123 } static const scan_key_list[] = TAGGED_ARRAY(KEY, 124 // up down right left pgup pgdn home end ins 125 {"UP", "\033[A"}, {"DOWN", "\033[B"}, {"RIGHT", "\033[C"}, {"LEFT", "\033[D"}, 126 {"PGUP", "\033[5~"}, {"PGDN", "\033[6~"}, {"HOME", "\033OH"}, 127 {"END", "\033OF"}, {"INSERT", "\033[2~"}, 128 129 {"F1", "\033OP"}, {"F2", "\033OQ"}, {"F3", "\033OR"}, {"F4", "\033OS"}, 130 {"F5", "\033[15~"}, {"F6", "\033[17~"}, {"F7", "\033[18~"}, 131 {"F8", "\033[19~"}, {"F9", "\033[20~"}, 132 133 {"SUP", "\033[1;2A"}, {"AUP", "\033[1;3A"}, {"CUP", "\033[1;5A"}, 134 {"SDOWN", "\033[1;2B"}, {"ADOWN", "\033[1;3B"}, {"CDOWN", "\033[1;5B"}, 135 {"SRIGHT", "\033[1;2C"}, {"ARIGHT", "\033[1;3C"}, {"CRIGHT", "\033[1;5C"}, 136 {"SLEFT", "\033[1;2D"}, {"ALEFT", "\033[1;3D"}, {"CLEFT", "\033[1;5D"}, 137 138 {"SF1", "\033O1;2P"}, {"AF1", "\033O1;3P"}, {"CF1", "\033[1;5P"} 139 ); 140 141 // Scan stdin for a keypress, parsing known escape sequences 142 // Blocks for miliwait miliseconds, none 0, forever if -1 143 // Returns: 0-255=literal, -1=EOF, -2=TIMEOUT, 256-...=index into scan_key_list 144 // >512 is x<<9+y<<21 145 // scratch space is necessary because last char of !seq could start new seq 146 // Zero out first byte of scratch before first call to scan_key 147 // block=0 allows fetching multiple characters before updating display 148 int scan_key(char *scratch, int miliwait) 149 { 150 struct pollfd pfd; 151 int maybe, i, j; 152 char *test; 153 154 for (;;) { 155 pfd.fd = 0; 156 pfd.events = POLLIN; 157 pfd.revents = 0; 158 159 maybe = 0; 160 if (*scratch) { 161 int pos[6]; 162 unsigned x, y; 163 164 // Check for return from terminal size probe 165 memset(pos, 0, 6*sizeof(int)); 166 scratch[(1+*scratch)&15] = 0; 167 sscanf(scratch+1, "\033%n[%n%3u%n;%n%3u%nR%n", pos, pos+1, &y, 168 pos+2, pos+3, &x, pos+4, pos+5); 169 if (pos[5]) { 170 // Recognized X/Y position, consume and return 171 *scratch = 0; 172 return 512+(x<<10)+(y<<20); 173 } else for (i=0; i<6; i++) if (pos[i]==*scratch) maybe = 1; 174 175 // Check sequences 176 for (i = 0; i<ARRAY_LEN(scan_key_list); i++) { 177 test = scan_key_list[i].seq; 178 for (j = 0; j<*scratch; j++) if (scratch[j+1] != test[j]) break; 179 if (j == *scratch) { 180 maybe = 1; 181 if (!test[j]) { 182 // We recognized current sequence: consume and return 183 *scratch = 0; 184 return 256+i; 185 } 186 } 187 } 188 189 // If current data can't be a known sequence, return next raw char 190 if (!maybe) break; 191 } 192 193 // Need more data to decide 194 195 // 30 miliseconds is about the gap between characters at 300 baud 196 if (maybe || miliwait != -1) 197 if (!xpoll(&pfd, 1, maybe ? 30 : miliwait)) break; 198 199 // Read 1 byte so we don't overshoot sequence match. (We can deviate 200 // and fail to match, but match consumes entire buffer.) 201 if (toys.signal || 1 != read(0, scratch+1+*scratch, 1)) 202 return toys.signal ? -3 : -1; 203 ++*scratch; 204 } 205 206 // Was not a sequence 207 if (!*scratch) return -2; 208 i = scratch[1]; 209 if (--*scratch) memmove(scratch+1, scratch+2, *scratch); 210 211 return i; 212 } 213 214 void tty_esc(char *s) 215 { 216 printf("\033[%s", s); 217 } 218 219 void tty_jump(int x, int y) 220 { 221 char s[32]; 222 223 sprintf(s, "%d;%dH", y+1, x+1); 224 tty_esc(s); 225 } 226 227 void tty_reset(void) 228 { 229 set_terminal(0, 0, 0); 230 tty_esc("?25h"); 231 tty_esc("0m"); 232 tty_jump(0, 999); 233 tty_esc("K"); 234 fflush(0); 235 } 236 237 // If you call set_terminal(), use sigatexit(tty_sigreset); 238 void tty_sigreset(int i) 239 { 240 tty_reset(); 241 _exit(i ? 128+i : 0); 242 } 243
