1 /* vi: set sw=4 ts=4: */
3 * script implementation for busybox
5 * pascal.bellard@ads-lu.com
7 * Based on code from util-linux v 2.12r
9 * The Regents of the University of California. All rights reserved.
11 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
14 //usage:#define script_trivial_usage
15 //usage: "[-afq" IF_SCRIPTREPLAY("t") "] [-c PROG] [OUTFILE]"
16 //usage:#define script_full_usage "\n\n"
18 //usage: "\n -a Append output"
19 //usage: "\n -c PROG Run PROG, not shell"
20 //usage: "\n -f Flush output after each write"
21 //usage: "\n -q Quiet"
22 //usage: IF_SCRIPTREPLAY(
23 //usage: "\n -t Send timing to stderr"
28 int script_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
29 int script_main(int argc UNUSED_PARAM, char **argv)
34 int attr_ok; /* NB: 0: ok */
37 char pty_line[GETPTY_BUFSIZE];
38 struct termios tt, rtt;
40 const char *fname = "typescript";
42 char shell_opt[] = "-i";
43 char *shell_arg = NULL;
53 static const char getopt_longopts[] ALIGN1 =
54 "append\0" No_argument "a"
55 "command\0" Required_argument "c"
56 "flush\0" No_argument "f"
57 "quiet\0" No_argument "q"
58 IF_SCRIPTREPLAY("timing\0" No_argument "t")
61 applet_long_options = getopt_longopts;
64 opt_complementary = "?1"; /* max one arg */
65 opt = getopt32(argv, "ac:fq" IF_SCRIPTREPLAY("t") , &shell_arg);
71 mode = O_CREAT|O_TRUNC|O_WRONLY;
73 mode = O_CREAT|O_APPEND|O_WRONLY;
79 printf("Script started, file is %s\n", fname);
81 shell = get_shell_name();
83 pty = xgetpty(pty_line);
85 /* get current stdin's tty params */
86 attr_ok = tcgetattr(0, &tt);
87 winsz_ok = ioctl(0, TIOCGWINSZ, (char *)&win);
92 tcsetattr(0, TCSAFLUSH, &rtt);
94 /* "script" from util-linux exits when child exits,
95 * we wouldn't wait for EOF from slave pty
96 * (output may be produced by grandchildren of child) */
97 signal(SIGCHLD, record_signo);
99 /* TODO: SIGWINCH? pass window size changes down to slave? */
101 child_pid = xvfork();
105 #define buf bb_common_bufsiz1
106 struct pollfd pfd[2];
107 int outfd, count, loop;
108 double oldtime = ENABLE_SCRIPTREPLAY ? time(NULL) : 0;
109 smallint fd_count = 2;
111 outfd = xopen(fname, mode);
113 pfd[0].events = POLLIN;
114 pfd[1].fd = STDIN_FILENO;
115 pfd[1].events = POLLIN;
116 ndelay_on(pty); /* this descriptor is not shared, can do this */
117 /* ndelay_on(STDIN_FILENO); - NO, stdin can be shared! Pity :( */
119 /* copy stdin to pty master input,
120 * copy pty master output to stdout and file */
121 /* TODO: don't use full_write's, use proper write buffering */
122 while (fd_count && !bb_got_signal) {
123 /* not safe_poll! we want SIGCHLD to EINTR poll */
124 if (poll(pfd, fd_count, -1) < 0 && errno != EINTR) {
125 /* If child exits too quickly, we may get EIO:
126 * for example, try "script -c true" */
129 if (pfd[0].revents) {
131 count = safe_read(pty, buf, sizeof(buf));
132 if (count <= 0 && errno != EAGAIN) {
133 /* err/eof from pty: exit */
137 if (ENABLE_SCRIPTREPLAY && (opt & OPT_t)) {
141 gettimeofday(&tv, NULL);
142 newtime = tv.tv_sec + (double) tv.tv_usec / 1000000;
143 fprintf(stderr, "%f %u\n", newtime - oldtime, count);
146 full_write(STDOUT_FILENO, buf, count);
147 full_write(outfd, buf, count);
153 if (pfd[1].revents) {
154 count = safe_read(STDIN_FILENO, buf, sizeof(buf));
156 /* err/eof from stdin: don't read stdin anymore */
160 full_write(pty, buf, count);
164 /* If loop was exited because SIGCHLD handler set bb_got_signal,
165 * there still can be some buffered output. But dont loop forever:
166 * we won't pump orphaned grandchildren's output indefinitely.
167 * Testcase: running this in script:
168 * exec dd if=/dev/zero bs=1M count=1
169 * must have "1+0 records in, 1+0 records out" captured too.
170 * (util-linux's script doesn't do this. buggy :) */
172 /* pty is in O_NONBLOCK mode, we exit as soon as buffer is empty */
173 while (--loop && (count = safe_read(pty, buf, sizeof(buf))) > 0) {
174 full_write(STDOUT_FILENO, buf, count);
175 full_write(outfd, buf, count);
179 tcsetattr(0, TCSAFLUSH, &tt);
181 printf("Script done, file is %s\n", fname);
185 /* child: make pty slave to be input, output, error; run shell */
186 close(pty); /* close pty master */
187 /* open pty slave to fd 0,1,2 */
189 xopen(pty_line, O_RDWR); /* uses fd 0 */
192 /* copy our original stdin tty's parameters to pty */
194 tcsetattr(0, TCSAFLUSH, &tt);
196 ioctl(0, TIOCSWINSZ, (char *)&win);
197 /* set pty as a controlling tty */
199 ioctl(0, TIOCSCTTY, 0 /* 0: don't forcibly steal */);
201 /* Non-ignored signals revert to SIG_DFL on exec anyway */
202 /*signal(SIGCHLD, SIG_DFL);*/
203 execl(shell, shell, shell_opt, shell_arg, (char *) NULL);
204 bb_simple_perror_msg_and_die(shell);