blob: c5063e8a17af03b81e00d7b4b1da99861566b459
1 | /* vi: set sw=4 ts=4: */ |
2 | /* |
3 | * script implementation for busybox |
4 | * |
5 | * pascal.bellard@ads-lu.com |
6 | * |
7 | * Based on code from util-linux v 2.12r |
8 | * Copyright (c) 1980 |
9 | * The Regents of the University of California. All rights reserved. |
10 | * |
11 | * Licensed under GPLv2 or later, see file LICENSE in this source tree. |
12 | */ |
13 | //config:config SCRIPT |
14 | //config: bool "script" |
15 | //config: default y |
16 | //config: help |
17 | //config: The script makes typescript of terminal session. |
18 | |
19 | //applet:IF_SCRIPT(APPLET(script, BB_DIR_USR_BIN, BB_SUID_DROP)) |
20 | |
21 | //kbuild:lib-$(CONFIG_SCRIPT) += script.o |
22 | |
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" |
32 | //usage: ) |
33 | |
34 | #include "libbb.h" |
35 | #include "common_bufsiz.h" |
36 | |
37 | int script_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; |
38 | int script_main(int argc UNUSED_PARAM, char **argv) |
39 | { |
40 | int opt; |
41 | int mode; |
42 | int child_pid; |
43 | int attr_ok; /* NB: 0: ok */ |
44 | int winsz_ok; |
45 | int pty; |
46 | char pty_line[GETPTY_BUFSIZE]; |
47 | struct termios tt, rtt; |
48 | struct winsize win; |
49 | const char *fname = "typescript"; |
50 | const char *shell; |
51 | char shell_opt[] = "-i"; |
52 | char *shell_arg = NULL; |
53 | enum { |
54 | OPT_a = (1 << 0), |
55 | OPT_c = (1 << 1), |
56 | OPT_f = (1 << 2), |
57 | OPT_q = (1 << 3), |
58 | OPT_t = (1 << 4), |
59 | }; |
60 | |
61 | #if ENABLE_LONG_OPTS |
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") |
68 | ; |
69 | |
70 | applet_long_options = getopt_longopts; |
71 | #endif |
72 | |
73 | opt_complementary = "?1"; /* max one arg */ |
74 | opt = getopt32(argv, "ac:fq" IF_SCRIPTREPLAY("t") , &shell_arg); |
75 | //argc -= optind; |
76 | argv += optind; |
77 | if (argv[0]) { |
78 | fname = argv[0]; |
79 | } |
80 | mode = O_CREAT|O_TRUNC|O_WRONLY; |
81 | if (opt & OPT_a) { |
82 | mode = O_CREAT|O_APPEND|O_WRONLY; |
83 | } |
84 | if (opt & OPT_c) { |
85 | shell_opt[1] = 'c'; |
86 | } |
87 | if (!(opt & OPT_q)) { |
88 | printf("Script started, file is %s\n", fname); |
89 | } |
90 | |
91 | shell = get_shell_name(); |
92 | |
93 | /* Some people run "script ... 0>&-". |
94 | * Our code assumes that STDIN_FILENO != pty. |
95 | * Ensure STDIN_FILENO is not closed: |
96 | */ |
97 | bb_sanitize_stdio(); |
98 | |
99 | pty = xgetpty(pty_line); |
100 | |
101 | /* get current stdin's tty params */ |
102 | attr_ok = tcgetattr(0, &tt); |
103 | winsz_ok = ioctl(0, TIOCGWINSZ, (char *)&win); |
104 | |
105 | rtt = tt; |
106 | cfmakeraw(&rtt); |
107 | rtt.c_lflag &= ~ECHO; |
108 | tcsetattr(0, TCSAFLUSH, &rtt); |
109 | |
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); |
114 | |
115 | /* TODO: SIGWINCH? pass window size changes down to slave? */ |
116 | |
117 | child_pid = xvfork(); |
118 | |
119 | if (child_pid) { |
120 | /* parent */ |
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(); |
127 | |
128 | outfd = xopen(fname, mode); |
129 | pfd[0].fd = pty; |
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 :( */ |
135 | |
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" */ |
144 | break; |
145 | } |
146 | if (pfd[0].revents) { |
147 | errno = 0; |
148 | count = safe_read(pty, buf, COMMON_BUFSIZE); |
149 | if (count <= 0 && errno != EAGAIN) { |
150 | /* err/eof from pty: exit */ |
151 | goto restore; |
152 | } |
153 | if (count > 0) { |
154 | if (ENABLE_SCRIPTREPLAY && (opt & OPT_t)) { |
155 | struct timeval tv; |
156 | double newtime; |
157 | |
158 | gettimeofday(&tv, NULL); |
159 | newtime = tv.tv_sec + (double) tv.tv_usec / 1000000; |
160 | fprintf(stderr, "%f %u\n", newtime - oldtime, count); |
161 | oldtime = newtime; |
162 | } |
163 | full_write(STDOUT_FILENO, buf, count); |
164 | full_write(outfd, buf, count); |
165 | if (opt & OPT_f) { |
166 | fsync(outfd); |
167 | } |
168 | } |
169 | } |
170 | if (pfd[1].revents) { |
171 | count = safe_read(STDIN_FILENO, buf, COMMON_BUFSIZE); |
172 | if (count <= 0) { |
173 | /* err/eof from stdin: don't read stdin anymore */ |
174 | pfd[1].revents = 0; |
175 | fd_count--; |
176 | } else { |
177 | full_write(pty, buf, count); |
178 | } |
179 | } |
180 | } |
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 :) */ |
188 | loop = 999; |
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); |
193 | } |
194 | restore: |
195 | if (attr_ok == 0) |
196 | tcsetattr(0, TCSAFLUSH, &tt); |
197 | if (!(opt & OPT_q)) |
198 | printf("Script done, file is %s\n", fname); |
199 | return EXIT_SUCCESS; |
200 | } |
201 | |
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 */ |
205 | close(0); |
206 | xopen(pty_line, O_RDWR); /* uses fd 0 */ |
207 | xdup2(0, 1); |
208 | xdup2(0, 2); |
209 | /* copy our original stdin tty's parameters to pty */ |
210 | if (attr_ok == 0) |
211 | tcsetattr(0, TCSAFLUSH, &tt); |
212 | if (winsz_ok == 0) |
213 | ioctl(0, TIOCSWINSZ, (char *)&win); |
214 | /* set pty as a controlling tty */ |
215 | setsid(); |
216 | ioctl(0, TIOCSCTTY, 0 /* 0: don't forcibly steal */); |
217 | |
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); |
222 | } |
223 |