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.
13 //config:config SCRIPT
14 //config: bool "script"
17 //config: The script makes typescript of terminal session.
19 //applet:IF_SCRIPT(APPLET(script, BB_DIR_USR_BIN, BB_SUID_DROP))
21 //kbuild:lib-$(CONFIG_SCRIPT) += script.o
23 //usage:#define script_trivial_usage
24 //usage: "[-afq" IF_SCRIPTREPLAY("t") "] [-c PROG] [OUTFILE]"
25 //usage:#define script_full_usage "\n\n"
26 //usage: " -a Append output"
27 //usage: "\n -c PROG Run PROG, not shell"
28 //usage: "\n -f Flush output after each write"
29 //usage: "\n -q Quiet"
30 //usage: IF_SCRIPTREPLAY(
31 //usage: "\n -t Send timing to stderr"
35 #include "common_bufsiz.h"
37 int script_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
38 int script_main(int argc UNUSED_PARAM, char **argv)
43 int attr_ok; /* NB: 0: ok */
46 char pty_line[GETPTY_BUFSIZE];
47 struct termios tt, rtt;
49 const char *fname = "typescript";
51 char shell_opt[] = "-i";
52 char *shell_arg = NULL;
62 static const char getopt_longopts[] ALIGN1 =
63 "append\0" No_argument "a"
64 "command\0" Required_argument "c"
65 "flush\0" No_argument "f"
66 "quiet\0" No_argument "q"
67 IF_SCRIPTREPLAY("timing\0" No_argument "t")
70 applet_long_options = getopt_longopts;
73 opt_complementary = "?1"; /* max one arg */
74 opt = getopt32(argv, "ac:fq" IF_SCRIPTREPLAY("t") , &shell_arg);
80 mode = O_CREAT|O_TRUNC|O_WRONLY;
82 mode = O_CREAT|O_APPEND|O_WRONLY;
88 printf("Script started, file is %s\n", fname);
91 shell = get_shell_name();
93 /* Some people run "script ... 0>&-".
94 * Our code assumes that STDIN_FILENO != pty.
95 * Ensure STDIN_FILENO is not closed:
99 pty = xgetpty(pty_line);
101 /* get current stdin's tty params */
102 attr_ok = tcgetattr(0, &tt);
103 winsz_ok = ioctl(0, TIOCGWINSZ, (char *)&win);
107 rtt.c_lflag &= ~ECHO;
108 tcsetattr(0, TCSAFLUSH, &rtt);
110 /* "script" from util-linux exits when child exits,
111 * we wouldn't wait for EOF from slave pty
112 * (output may be produced by grandchildren of child) */
113 signal(SIGCHLD, record_signo);
115 /* TODO: SIGWINCH? pass window size changes down to slave? */
117 child_pid = xvfork();
121 struct pollfd pfd[2];
122 int outfd, count, loop;
123 double oldtime = ENABLE_SCRIPTREPLAY ? time(NULL) : 0;
124 smallint fd_count = 2;
125 #define buf bb_common_bufsiz1
126 setup_common_bufsiz();
128 outfd = xopen(fname, mode);
130 pfd[0].events = POLLIN;
131 pfd[1].fd = STDIN_FILENO;
132 pfd[1].events = POLLIN;
133 ndelay_on(pty); /* this descriptor is not shared, can do this */
134 /* ndelay_on(STDIN_FILENO); - NO, stdin can be shared! Pity :( */
136 /* copy stdin to pty master input,
137 * copy pty master output to stdout and file */
138 /* TODO: don't use full_write's, use proper write buffering */
139 while (fd_count && !bb_got_signal) {
140 /* not safe_poll! we want SIGCHLD to EINTR poll */
141 if (poll(pfd, fd_count, -1) < 0 && errno != EINTR) {
142 /* If child exits too quickly, we may get EIO:
143 * for example, try "script -c true" */
146 if (pfd[0].revents) {
148 count = safe_read(pty, buf, COMMON_BUFSIZE);
149 if (count <= 0 && errno != EAGAIN) {
150 /* err/eof from pty: exit */
154 if (ENABLE_SCRIPTREPLAY && (opt & OPT_t)) {
158 gettimeofday(&tv, NULL);
159 newtime = tv.tv_sec + (double) tv.tv_usec / 1000000;
160 fprintf(stderr, "%f %u\n", newtime - oldtime, count);
163 full_write(STDOUT_FILENO, buf, count);
164 full_write(outfd, buf, count);
170 if (pfd[1].revents) {
171 count = safe_read(STDIN_FILENO, buf, COMMON_BUFSIZE);
173 /* err/eof from stdin: don't read stdin anymore */
177 full_write(pty, buf, count);
181 /* If loop was exited because SIGCHLD handler set bb_got_signal,
182 * there still can be some buffered output. But dont loop forever:
183 * we won't pump orphaned grandchildren's output indefinitely.
184 * Testcase: running this in script:
185 * exec dd if=/dev/zero bs=1M count=1
186 * must have "1+0 records in, 1+0 records out" captured too.
187 * (util-linux's script doesn't do this. buggy :) */
189 /* pty is in O_NONBLOCK mode, we exit as soon as buffer is empty */
190 while (--loop && (count = safe_read(pty, buf, COMMON_BUFSIZE)) > 0) {
191 full_write(STDOUT_FILENO, buf, count);
192 full_write(outfd, buf, count);
196 tcsetattr(0, TCSAFLUSH, &tt);
198 printf("Script done, file is %s\n", fname);
202 /* child: make pty slave to be input, output, error; run shell */
203 close(pty); /* close pty master */
204 /* open pty slave to fd 0,1,2 */
206 xopen(pty_line, O_RDWR); /* uses fd 0 */
209 /* copy our original stdin tty's parameters to pty */
211 tcsetattr(0, TCSAFLUSH, &tt);
213 ioctl(0, TIOCSWINSZ, (char *)&win);
214 /* set pty as a controlling tty */
216 ioctl(0, TIOCSCTTY, 0 /* 0: don't forcibly steal */);
218 /* Non-ignored signals revert to SIG_DFL on exec anyway */
219 /*signal(SIGCHLD, SIG_DFL);*/
220 execl(shell, shell, shell_opt, shell_arg, (char *) NULL);
221 bb_simple_perror_msg_and_die(shell);