| 1 | /* -*-c-*- |
| 2 | * |
| 3 | * Pause for a while |
| 4 | * |
| 5 | * (c) 1999 Mark Wooding |
| 6 | */ |
| 7 | |
| 8 | /*----- Licensing notice --------------------------------------------------* |
| 9 | * |
| 10 | * This file is part of Pause. |
| 11 | * |
| 12 | * Pause is free software; you can redistribute it and/or modify |
| 13 | * it under the terms of the GNU General Public License as published by |
| 14 | * the Free Software Foundation; either version 2 of the License, or |
| 15 | * (at your option) any later ersion. |
| 16 | * |
| 17 | * Pause is distributed in the hope that it will be useful, |
| 18 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 19 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 20 | * GNU General Public License for more details. |
| 21 | * |
| 22 | * You should have received a copy of the GNU General Public License |
| 23 | * along with Pause; if not, write to the Free Software Foundation, |
| 24 | * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
| 25 | */ |
| 26 | |
| 27 | /*----- Header files ------------------------------------------------------*/ |
| 28 | |
| 29 | #include <errno.h> |
| 30 | #include <math.h> |
| 31 | #include <signal.h> |
| 32 | #include <stdio.h> |
| 33 | #include <stdlib.h> |
| 34 | #include <string.h> |
| 35 | |
| 36 | #include <sys/types.h> |
| 37 | #include <sys/time.h> |
| 38 | #include <unistd.h> |
| 39 | #include <termios.h> |
| 40 | |
| 41 | #include <mLib/mdwopt.h> |
| 42 | #include <mLib/quis.h> |
| 43 | #include <mLib/report.h> |
| 44 | #include <mLib/tv.h> |
| 45 | |
| 46 | /*----- Static variables --------------------------------------------------*/ |
| 47 | |
| 48 | static struct termios ts_old, ts; |
| 49 | |
| 50 | /*----- Main code ---------------------------------------------------------*/ |
| 51 | |
| 52 | /* --- @sig@ --- * |
| 53 | * |
| 54 | * Arguments: @int s@ = signal number |
| 55 | * |
| 56 | * Returns: Doesn't. |
| 57 | * |
| 58 | * Use: Handles various fatal signals by resetting the terminal state |
| 59 | * and re-emitting the signal. |
| 60 | */ |
| 61 | |
| 62 | static void sig(int s) |
| 63 | { |
| 64 | tcsetattr(STDIN_FILENO, TCSAFLUSH, &ts_old); |
| 65 | signal(s, SIG_DFL); |
| 66 | raise(s); |
| 67 | } |
| 68 | |
| 69 | /* --- @suspend@ --- * |
| 70 | * |
| 71 | * Arguments: @int s@ = signal number |
| 72 | * |
| 73 | * Returns: --- |
| 74 | * |
| 75 | * Use: Handles a job control signal, as recommended in APUE. It |
| 76 | * resets the terminal state, resets the signal disposition, |
| 77 | * unblocks the signal and re-emits it (so that the shell |
| 78 | * shows the right message). When that call returns, the |
| 79 | * signal handler is reattached, and the terminal state is set |
| 80 | * again. |
| 81 | */ |
| 82 | |
| 83 | static void suspend(int s) |
| 84 | { |
| 85 | sigset_t ss; |
| 86 | |
| 87 | tcsetattr(STDIN_FILENO, TCSAFLUSH, &ts_old); |
| 88 | signal(s, SIG_DFL); |
| 89 | sigemptyset(&ss); |
| 90 | sigaddset(&ss, s); |
| 91 | sigprocmask(SIG_UNBLOCK, &ss, 0); |
| 92 | raise(s); |
| 93 | signal(s, suspend); |
| 94 | tcsetattr(STDIN_FILENO, TCSAFLUSH, &ts); |
| 95 | } |
| 96 | |
| 97 | /* --- Traditional GNUey help options --- */ |
| 98 | |
| 99 | static void usage(FILE *fp) |
| 100 | { |
| 101 | pquis(fp, "Usage: $ [time]\n"); |
| 102 | } |
| 103 | |
| 104 | static void version(FILE *fp) |
| 105 | { |
| 106 | pquis(fp, "$ version " VERSION "\n"); |
| 107 | } |
| 108 | |
| 109 | static void help(FILE *fp) |
| 110 | { |
| 111 | version(fp); |
| 112 | fputc('\n', fp); |
| 113 | usage(fp); |
| 114 | pquis(fp, "\n\ |
| 115 | Pauses until a key is pressed or an optional time-limit expires. The\n\ |
| 116 | time is given as a floating point number with an option suffix of `s',\n\ |
| 117 | `m', `h' or `d' (for `seconds', `minutes', `hours' or `days'\n\ |
| 118 | respectively).\n\ |
| 119 | \n\ |
| 120 | Options available:\n\ |
| 121 | \n\ |
| 122 | -h, --help Show this help message.\n\ |
| 123 | -v, --version Show program's version number.\n\ |
| 124 | -u, --usage Show terse usage summary.\n\ |
| 125 | "); |
| 126 | } |
| 127 | |
| 128 | /* --- @main@ --- * |
| 129 | * |
| 130 | * Arguments: @int argc@ = number of command line arguments |
| 131 | * @char *argv[]@ = vector of command line arguments |
| 132 | * |
| 133 | * Returns: Nonzero if it failed, zero if everything went well. |
| 134 | * |
| 135 | * Use: Souped-up version of `sleep'. |
| 136 | */ |
| 137 | |
| 138 | int main(int argc, char *argv[]) |
| 139 | { |
| 140 | struct termios ts; |
| 141 | unsigned f = 0; |
| 142 | struct timeval when; |
| 143 | |
| 144 | enum { |
| 145 | f_bogus = 1u, |
| 146 | f_timer = 2u, |
| 147 | f_key = 4u |
| 148 | }; |
| 149 | |
| 150 | /* --- Library initialization --- */ |
| 151 | |
| 152 | ego(argv[0]); |
| 153 | |
| 154 | /* --- Parse command line options --- */ |
| 155 | |
| 156 | for (;;) { |
| 157 | static struct option opt[] = { |
| 158 | { "help", 0, 0, 'h' }, |
| 159 | { "version", 0, 0, 'v' }, |
| 160 | { "usage", 0, 0, 'u' }, |
| 161 | { 0, 0, 0, 0 } |
| 162 | }; |
| 163 | int i = mdwopt(argc, argv, "hvu", opt, 0, 0, 0); |
| 164 | if (i < 0) |
| 165 | break; |
| 166 | switch (i) { |
| 167 | case 'h': |
| 168 | help(stderr); |
| 169 | exit(0); |
| 170 | case 'v': |
| 171 | version(stderr); |
| 172 | exit(0); |
| 173 | case 'u': |
| 174 | usage(stderr); |
| 175 | exit(0); |
| 176 | default: |
| 177 | f |= f_bogus; |
| 178 | break; |
| 179 | } |
| 180 | } |
| 181 | |
| 182 | /* --- Parse a timer spec --- */ |
| 183 | |
| 184 | if (!(f & f_bogus) && optind < argc) { |
| 185 | const char *p =argv[optind++]; |
| 186 | char *q; |
| 187 | double t = strtod(p, &q); |
| 188 | switch (*q) { |
| 189 | case 'd': t *= 24; |
| 190 | case 'h': t *= 60; |
| 191 | case 'm': t *= 60; |
| 192 | case 's': if (q[1] != 0) |
| 193 | default: t = 0; |
| 194 | case 0: break; |
| 195 | } |
| 196 | if (t <= 0) |
| 197 | die(1, "bad time specification `%s'", p); |
| 198 | gettimeofday(&when, 0); |
| 199 | TV_ADDL(&when, &when, t, (t - floor(t)) * MILLION); |
| 200 | f |= f_timer; |
| 201 | } |
| 202 | |
| 203 | /* --- Report a syntax error --- */ |
| 204 | |
| 205 | if (optind < argc) |
| 206 | f |= f_bogus; |
| 207 | if (f & f_bogus) { |
| 208 | usage(stderr); |
| 209 | exit(1); |
| 210 | } |
| 211 | |
| 212 | /* --- Set up terminal for single keypresses --- */ |
| 213 | |
| 214 | if (tcgetattr(STDIN_FILENO, &ts_old) == 0) { |
| 215 | static struct { int sig; void (*func)(int); } sigs[] = { |
| 216 | { SIGINT, sig }, |
| 217 | { SIGQUIT, sig }, |
| 218 | { SIGTERM, sig }, |
| 219 | { SIGTSTP, suspend }, |
| 220 | { 0, 0 } |
| 221 | }; |
| 222 | int i; |
| 223 | |
| 224 | /* --- Set up the new terminal attributes --- */ |
| 225 | |
| 226 | ts = ts_old; |
| 227 | ts.c_lflag &= ~(ECHO | ICANON | TOSTOP); |
| 228 | |
| 229 | /* --- Set up signal handlers to reset attributes --- */ |
| 230 | |
| 231 | for (i = 0; sigs[i].sig; i++) { |
| 232 | struct sigaction sa; |
| 233 | sigaction(sigs[i].sig, 0, &sa); |
| 234 | if (sa.sa_handler != SIG_IGN) |
| 235 | signal(sigs[i].sig, sigs[i].func); |
| 236 | } |
| 237 | signal(SIGTTIN, suspend); |
| 238 | |
| 239 | /* --- Commit the terminal attribute changes --- */ |
| 240 | |
| 241 | tcsetattr(STDIN_FILENO, TCSAFLUSH, &ts); |
| 242 | f |= f_key; |
| 243 | } |
| 244 | |
| 245 | /* --- Main loop --- */ |
| 246 | |
| 247 | for (;;) { |
| 248 | fd_set fd, *pfd; |
| 249 | int maxfd; |
| 250 | struct timeval tv, *ptv; |
| 251 | |
| 252 | /* --- Wait for a keypress --- */ |
| 253 | |
| 254 | if (f & f_key) { |
| 255 | FD_ZERO(&fd); |
| 256 | FD_SET(STDIN_FILENO, &fd); |
| 257 | maxfd = STDIN_FILENO + 1; |
| 258 | pfd = &fd; |
| 259 | } else { |
| 260 | maxfd = 0; |
| 261 | pfd = 0; |
| 262 | } |
| 263 | |
| 264 | /* --- Wait for the timer to expire --- */ |
| 265 | |
| 266 | if (f & f_timer) { |
| 267 | gettimeofday(&tv, 0); |
| 268 | TV_SUB(&tv, &when, &tv); |
| 269 | ptv = &tv; |
| 270 | } else |
| 271 | ptv = 0; |
| 272 | |
| 273 | /* --- See what interesting things have happened --- */ |
| 274 | |
| 275 | if (select(maxfd, pfd, 0, 0, ptv) < 0) { |
| 276 | if (errno == EINTR || errno == EAGAIN) |
| 277 | continue; |
| 278 | die(1, "error in select: %s", strerror(errno)); |
| 279 | } |
| 280 | |
| 281 | /* --- Check the timer --- */ |
| 282 | |
| 283 | if (f & f_timer) { |
| 284 | gettimeofday(&tv, 0); |
| 285 | if (TV_CMP(&tv, >=, &when)) |
| 286 | break; |
| 287 | } |
| 288 | |
| 289 | /* --- Check the key state --- */ |
| 290 | |
| 291 | if (f & f_key && FD_ISSET(STDIN_FILENO, &fd)) |
| 292 | break; |
| 293 | } |
| 294 | |
| 295 | /* --- See what gives --- */ |
| 296 | |
| 297 | if (f & f_key) |
| 298 | tcsetattr(STDIN_FILENO, TCSAFLUSH, &ts_old); |
| 299 | return (0); |
| 300 | } |
| 301 | |
| 302 | /*----- That's all, folks -------------------------------------------------*/ |