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 (8 kb)"
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: "[-afqt] [-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: "\n -t Send timing to stderr"
34 //-e: return exit code of the child
36 //FYI (reported as bbox bug #2749):
37 // > script -q -c 'echo -e -n "1\n2\n3\n"' /dev/null </dev/null >123.txt
38 // > The output file on full-blown ubuntu system contains 6 bytes.
39 // > Output on Busybox system (arm-linux) contains extra '\r' byte in each line.
40 //however, in my test, "script" from util-linux-2.28 seems to also add '\r' bytes.
43 #include "common_bufsiz.h"
45 int script_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
46 int script_main(int argc UNUSED_PARAM, char **argv)
51 int attr_ok; /* NB: 0: ok */
54 char pty_line[GETPTY_BUFSIZE];
55 struct termios tt, rtt;
57 const char *fname = "typescript";
59 char shell_opt[] = "-i";
60 char *shell_arg = NULL;
70 static const char getopt_longopts[] ALIGN1 =
71 "append\0" No_argument "a"
72 "command\0" Required_argument "c"
73 "flush\0" No_argument "f"
74 "quiet\0" No_argument "q"
75 "timing\0" No_argument "t"
78 applet_long_options = getopt_longopts;
81 opt_complementary = "?1"; /* max one arg */
82 opt = getopt32(argv, "ac:fqt", &shell_arg);
88 mode = O_CREAT|O_TRUNC|O_WRONLY;
90 mode = O_CREAT|O_APPEND|O_WRONLY;
96 printf("Script started, file is %s\n", fname);
99 shell = get_shell_name();
101 /* Some people run "script ... 0>&-".
102 * Our code assumes that STDIN_FILENO != pty.
103 * Ensure STDIN_FILENO is not closed:
107 pty = xgetpty(pty_line);
109 /* get current stdin's tty params */
110 attr_ok = tcgetattr(0, &tt);
111 winsz_ok = ioctl(0, TIOCGWINSZ, (char *)&win);
115 rtt.c_lflag &= ~ECHO;
116 tcsetattr(0, TCSAFLUSH, &rtt);
118 /* "script" from util-linux exits when child exits,
119 * we wouldn't wait for EOF from slave pty
120 * (output may be produced by grandchildren of child) */
121 signal(SIGCHLD, record_signo);
123 /* TODO: SIGWINCH? pass window size changes down to slave? */
125 child_pid = xvfork();
129 struct pollfd pfd[2];
130 int outfd, count, loop;
131 double oldtime = time(NULL);
132 smallint fd_count = 2;
133 #define buf bb_common_bufsiz1
134 setup_common_bufsiz();
136 outfd = xopen(fname, mode);
138 pfd[0].events = POLLIN;
139 pfd[1].fd = STDIN_FILENO;
140 pfd[1].events = POLLIN;
141 ndelay_on(pty); /* this descriptor is not shared, can do this */
142 /* ndelay_on(STDIN_FILENO); - NO, stdin can be shared! Pity :( */
144 /* copy stdin to pty master input,
145 * copy pty master output to stdout and file */
146 /* TODO: don't use full_write's, use proper write buffering */
147 while (fd_count && !bb_got_signal) {
148 /* not safe_poll! we want SIGCHLD to EINTR poll */
149 if (poll(pfd, fd_count, -1) < 0 && errno != EINTR) {
150 /* If child exits too quickly, we may get EIO:
151 * for example, try "script -c true" */
154 if (pfd[0].revents) {
156 count = safe_read(pty, buf, COMMON_BUFSIZE);
157 if (count <= 0 && errno != EAGAIN) {
158 /* err/eof from pty: exit */
166 gettimeofday(&tv, NULL);
167 newtime = tv.tv_sec + (double) tv.tv_usec / 1000000;
168 fprintf(stderr, "%f %u\n", newtime - oldtime, count);
171 full_write(STDOUT_FILENO, buf, count);
172 full_write(outfd, buf, count);
178 if (pfd[1].revents) {
179 count = safe_read(STDIN_FILENO, buf, COMMON_BUFSIZE);
181 /* err/eof from stdin: don't read stdin anymore */
185 full_write(pty, buf, count);
189 /* If loop was exited because SIGCHLD handler set bb_got_signal,
190 * there still can be some buffered output. But dont loop forever:
191 * we won't pump orphaned grandchildren's output indefinitely.
192 * Testcase: running this in script:
193 * exec dd if=/dev/zero bs=1M count=1
194 * must have "1+0 records in, 1+0 records out" captured too.
195 * (util-linux's script doesn't do this. buggy :) */
197 /* pty is in O_NONBLOCK mode, we exit as soon as buffer is empty */
198 while (--loop && (count = safe_read(pty, buf, COMMON_BUFSIZE)) > 0) {
199 full_write(STDOUT_FILENO, buf, count);
200 full_write(outfd, buf, count);
204 tcsetattr(0, TCSAFLUSH, &tt);
206 printf("Script done, file is %s\n", fname);
210 /* child: make pty slave to be input, output, error; run shell */
211 close(pty); /* close pty master */
212 /* open pty slave to fd 0,1,2 */
214 xopen(pty_line, O_RDWR); /* uses fd 0 */
217 /* copy our original stdin tty's parameters to pty */
219 tcsetattr(0, TCSAFLUSH, &tt);
221 ioctl(0, TIOCSWINSZ, (char *)&win);
222 /* set pty as a controlling tty */
224 ioctl(0, TIOCSCTTY, 0 /* 0: don't forcibly steal */);
226 /* Non-ignored signals revert to SIG_DFL on exec anyway */
227 /*signal(SIGCHLD, SIG_DFL);*/
228 execl(shell, shell, shell_opt, shell_arg, (char *) NULL);
229 bb_simple_perror_msg_and_die(shell);