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"
17 //usage: " -a Append output"
18 //usage: "\n -c PROG Run PROG, not shell"
19 //usage: "\n -f Flush output after each write"
20 //usage: "\n -q Quiet"
21 //usage: IF_SCRIPTREPLAY(
22 //usage: "\n -t Send timing to stderr"
27 int script_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
28 int script_main(int argc UNUSED_PARAM, char **argv)
33 int attr_ok; /* NB: 0: ok */
36 char pty_line[GETPTY_BUFSIZE];
37 struct termios tt, rtt;
39 const char *fname = "typescript";
41 char shell_opt[] = "-i";
42 char *shell_arg = NULL;
52 static const char getopt_longopts[] ALIGN1 =
53 "append\0" No_argument "a"
54 "command\0" Required_argument "c"
55 "flush\0" No_argument "f"
56 "quiet\0" No_argument "q"
57 IF_SCRIPTREPLAY("timing\0" No_argument "t")
60 applet_long_options = getopt_longopts;
63 opt_complementary = "?1"; /* max one arg */
64 opt = getopt32(argv, "ac:fq" IF_SCRIPTREPLAY("t") , &shell_arg);
70 mode = O_CREAT|O_TRUNC|O_WRONLY;
72 mode = O_CREAT|O_APPEND|O_WRONLY;
78 printf("Script started, file is %s\n", fname);
80 shell = get_shell_name();
82 pty = xgetpty(pty_line);
84 /* get current stdin's tty params */
85 attr_ok = tcgetattr(0, &tt);
86 winsz_ok = ioctl(0, TIOCGWINSZ, (char *)&win);
91 tcsetattr(0, TCSAFLUSH, &rtt);
93 /* "script" from util-linux exits when child exits,
94 * we wouldn't wait for EOF from slave pty
95 * (output may be produced by grandchildren of child) */
96 signal(SIGCHLD, record_signo);
98 /* TODO: SIGWINCH? pass window size changes down to slave? */
100 child_pid = xvfork();
104 #define buf bb_common_bufsiz1
105 struct pollfd pfd[2];
106 int outfd, count, loop;
107 double oldtime = ENABLE_SCRIPTREPLAY ? time(NULL) : 0;
108 smallint fd_count = 2;
110 outfd = xopen(fname, mode);
112 pfd[0].events = POLLIN;
113 pfd[1].fd = STDIN_FILENO;
114 pfd[1].events = POLLIN;
115 ndelay_on(pty); /* this descriptor is not shared, can do this */
116 /* ndelay_on(STDIN_FILENO); - NO, stdin can be shared! Pity :( */
118 /* copy stdin to pty master input,
119 * copy pty master output to stdout and file */
120 /* TODO: don't use full_write's, use proper write buffering */
121 while (fd_count && !bb_got_signal) {
122 /* not safe_poll! we want SIGCHLD to EINTR poll */
123 if (poll(pfd, fd_count, -1) < 0 && errno != EINTR) {
124 /* If child exits too quickly, we may get EIO:
125 * for example, try "script -c true" */
128 if (pfd[0].revents) {
130 count = safe_read(pty, buf, sizeof(buf));
131 if (count <= 0 && errno != EAGAIN) {
132 /* err/eof from pty: exit */
136 if (ENABLE_SCRIPTREPLAY && (opt & OPT_t)) {
140 gettimeofday(&tv, NULL);
141 newtime = tv.tv_sec + (double) tv.tv_usec / 1000000;
142 fprintf(stderr, "%f %u\n", newtime - oldtime, count);
145 full_write(STDOUT_FILENO, buf, count);
146 full_write(outfd, buf, count);
152 if (pfd[1].revents) {
153 count = safe_read(STDIN_FILENO, buf, sizeof(buf));
155 /* err/eof from stdin: don't read stdin anymore */
159 full_write(pty, buf, count);
163 /* If loop was exited because SIGCHLD handler set bb_got_signal,
164 * there still can be some buffered output. But dont loop forever:
165 * we won't pump orphaned grandchildren's output indefinitely.
166 * Testcase: running this in script:
167 * exec dd if=/dev/zero bs=1M count=1
168 * must have "1+0 records in, 1+0 records out" captured too.
169 * (util-linux's script doesn't do this. buggy :) */
171 /* pty is in O_NONBLOCK mode, we exit as soon as buffer is empty */
172 while (--loop && (count = safe_read(pty, buf, sizeof(buf))) > 0) {
173 full_write(STDOUT_FILENO, buf, count);
174 full_write(outfd, buf, count);
178 tcsetattr(0, TCSAFLUSH, &tt);
180 printf("Script done, file is %s\n", fname);
184 /* child: make pty slave to be input, output, error; run shell */
185 close(pty); /* close pty master */
186 /* open pty slave to fd 0,1,2 */
188 xopen(pty_line, O_RDWR); /* uses fd 0 */
191 /* copy our original stdin tty's parameters to pty */
193 tcsetattr(0, TCSAFLUSH, &tt);
195 ioctl(0, TIOCSWINSZ, (char *)&win);
196 /* set pty as a controlling tty */
198 ioctl(0, TIOCSCTTY, 0 /* 0: don't forcibly steal */);
200 /* Non-ignored signals revert to SIG_DFL on exec anyway */
201 /*signal(SIGCHLD, SIG_DFL);*/
202 execl(shell, shell, shell_opt, shell_arg, (char *) NULL);
203 bb_simple_perror_msg_and_die(shell);