One item to poll() more is a lot less work for system than separete input and output processes. Addresses: https://github.com/karelzak/util-linux/pull/62 CC: Wolfgang Richter <wolf@xxxxxxxxxx> CC: Ruediger Meier <ruediger.meier@xxxxxxxxxxx> Signed-off-by: Sami Kerola <kerolasa@xxxxxx> --- term-utils/script.c | 220 ++++++++++++---------------------------------------- 1 file changed, 51 insertions(+), 169 deletions(-) diff --git a/term-utils/script.c b/term-utils/script.c index 456355e..4a761c6 100644 --- a/term-utils/script.c +++ b/term-utils/script.c @@ -82,7 +82,7 @@ #define DEFAULT_OUTPUT "typescript" -enum { POLLFDS = 2 }; +enum { POLLFDS = 3 }; struct script_control { char *shell; /* shell to be executed */ @@ -93,7 +93,6 @@ struct script_control { int master; /* pseudoterminal master file descriptor */ int slave; /* pseudoterminal slave file descriptor */ pid_t child; /* child pid */ - pid_t subchild; /* subchild pid */ int childstatus; /* child process exit value */ struct termios tt; /* slave terminal runtime attributes */ struct winsize win; /* terminal window size */ @@ -157,39 +156,15 @@ static void my_strftime(char *buf, size_t len, const char *fmt, const struct tm static void __attribute__((__noreturn__)) done(struct script_control *ctl) { - time_t tvec; - - if (ctl->subchild) { - /* output process */ - if (ctl->typescriptfp) { - if (!ctl->qflg) { - char buf[BUFSIZ]; - tvec = time((time_t *)NULL); - my_strftime(buf, sizeof buf, "%c\n", localtime(&tvec)); - fprintf(ctl->typescriptfp, _("\nScript done on %s"), buf); - } - if (close_stream(ctl->typescriptfp) != 0) - errx(EXIT_FAILURE, _("write error")); - ctl->typescriptfp = NULL; - } - if (ctl->timingfp && close_stream(ctl->timingfp) != 0) - errx(EXIT_FAILURE, _("write error")); - ctl->timingfp = NULL; - - close(ctl->master); - ctl->master = -1; - } else { - /* input process */ - if (ctl->isterm) - tcsetattr(STDIN_FILENO, TCSADRAIN, &ctl->tt); - if (!ctl->qflg) - printf(_("Script done, file is %s\n"), ctl->fname); + if (ctl->isterm) + tcsetattr(STDIN_FILENO, TCSADRAIN, &ctl->tt); + if (!ctl->qflg) + printf(_("Script done, file is %s\n"), ctl->fname); #ifdef HAVE_LIBUTEMPTER - if (ctl->master >= 0) - utempter_remove_record(ctl->master); + if (ctl->master >= 0) + utempter_remove_record(ctl->master); #endif - kill(ctl->child, SIGTERM); /* make sure we don't create orphans */ - } + kill(ctl->child, SIGTERM); /* make sure we don't create orphans */ if (ctl->eflg) { if (WIFSIGNALED(ctl->childstatus)) @@ -206,15 +181,6 @@ static void fail(struct script_control *ctl) done(ctl); } -static void wait_for_empty_fd(struct script_control *ctl, int fd) -{ - struct pollfd fds[] = { - {.fd = fd, .events = POLLIN} - }; - - while (ctl->die == 0 && poll(fds, 1, 100) == 1) ; -} - static void finish(struct script_control *ctl, int wait) { int status; @@ -231,97 +197,6 @@ static void finish(struct script_control *ctl, int wait) errno = errsv; } -static void doinput(struct script_control *ctl) -{ - char ibuf[BUFSIZ]; - struct pollfd pfd[POLLFDS]; - int ret, i; - ssize_t bytes; - - /* close things irrelevant for this process */ - if (ctl->typescriptfp) - fclose(ctl->typescriptfp); - if (ctl->timingfp) - fclose(ctl->timingfp); - ctl->typescriptfp = ctl->timingfp = NULL; - - pfd[0].fd = STDIN_FILENO; - pfd[0].events = POLLIN; - pfd[1].fd = ctl->sigfd; - pfd[1].events = POLLIN | POLLERR | POLLHUP; - - while (!ctl->die) { - /* wait for input or signal */ - ret = poll(pfd, POLLFDS, -1); - if (ret < 0) { - if (errno == EAGAIN) - continue; - warn(_("poll failed")); - fail(ctl); - } - for (i = 0; i < POLLFDS; i++) { - if (pfd[i].revents == 0) - continue; - if (i == 0 && (bytes = read(pfd[i].fd, ibuf, BUFSIZ)) > 0) { - if (write_all(ctl->master, ibuf, bytes)) { - warn(_("write failed")); - fail(ctl); - } - } - if (i == 1) { - struct signalfd_siginfo info; - ssize_t bytes; - - bytes = read(pfd[i].fd, &info, sizeof(info)); - assert(bytes == sizeof(info)); - switch (info.ssi_signo) { - case SIGCHLD: - finish(ctl, 0); - break; - case SIGWINCH: - if (ctl->isterm) { - ioctl(STDIN_FILENO, TIOCGWINSZ, (char *)&ctl->win); - ioctl(ctl->slave, TIOCSWINSZ, (char *)&ctl->win); - } - break; - default: - abort(); - } - } - } - } - - /* To be sure that we don't miss any data */ - wait_for_empty_fd(ctl, ctl->slave); - wait_for_empty_fd(ctl, ctl->master); - - if (ctl->die == 0) { - /* - * Forward EOF from stdin (detected by read() above) to slave - * (shell) to correctly terminate the session. It seems we have - * to wait for empty terminal FDs otherwise EOF maybe ignored - * (why?) and typescript is incomplete. -- kzak Dec-2013 - * - * We usually use this when stdin is not a tty, for example: - * echo "ps" | script - */ - int c = DEF_EOF; - - if (write_all(ctl->master, &c, 1)) { - warn(_("write failed")); - fail(ctl); - } - - /* wait for "exit" message from shell before we print "Script - * done" in done() */ - wait_for_empty_fd(ctl, ctl->master); - } - - if (!ctl->die) - finish(ctl, 1); /* wait for children */ - done(ctl); -} - static void write_output(struct script_control *ctl, char *obuf, ssize_t bytes, double *oldtime) { @@ -349,34 +224,31 @@ static void write_output(struct script_control *ctl, char *obuf, } } - -static void dooutput(struct script_control *ctl) +static void do_io(struct script_control *ctl) { - char obuf[BUFSIZ]; + char buf[BUFSIZ]; struct pollfd pfd[POLLFDS]; int ret, i; ssize_t bytes; double oldtime = time(NULL); - close(STDIN_FILENO); -#ifdef HAVE_LIBUTIL - close(ctl->slave); -#endif if (ctl->tflg && !ctl->timingfp) ctl->timingfp = fdopen(STDERR_FILENO, "w"); + pfd[0].fd = STDIN_FILENO; + pfd[0].events = POLLIN; + pfd[1].fd = ctl->master; + pfd[1].events = POLLIN; + pfd[2].fd = ctl->sigfd; + pfd[2].events = POLLIN | POLLERR | POLLHUP; + if (!ctl->qflg) { time_t tvec = time((time_t *)NULL); - my_strftime(obuf, sizeof obuf, "%c\n", localtime(&tvec)); - fprintf(ctl->typescriptfp, _("Script started on %s"), obuf); + my_strftime(buf, sizeof buf, "%c\n", localtime(&tvec)); + fprintf(ctl->typescriptfp, _("Script started on %s"), buf); } - pfd[0].fd = ctl->master; - pfd[0].events = POLLIN; - pfd[1].fd = ctl->sigfd; - pfd[1].events = POLLIN | POLLERR | POLLHUP; - - while (1) { + while (!ctl->die) { /* wait for input or signal */ ret = poll(pfd, POLLFDS, -1); if (ret < 0) { @@ -388,17 +260,33 @@ static void dooutput(struct script_control *ctl) for (i = 0; i < POLLFDS; i++) { if (pfd[i].revents == 0) continue; - if (i == 0) { - bytes = read(pfd[i].fd, obuf, BUFSIZ); + if (i < 2) { + bytes = read(pfd[i].fd, buf, BUFSIZ); if (bytes < 0) { if (errno == EAGAIN) continue; fail(ctl); } - write_output(ctl, obuf, bytes, &oldtime); + if (i == 0) { + if (write_all(ctl->master, buf, bytes)) { + warn(_("write failed")); + fail(ctl); + } else + + /* without sync write_output() + * will write both input & + * shell output that looks like + * double echoing */ + fdatasync(ctl->master); + if (!ctl->isterm && !feof(stdin)) { + int c = DEF_EOF; + write_all(ctl->master, &c, 1); + } + } else + write_output(ctl, buf, bytes, &oldtime); continue; } - if (i == 1) { + if (i == 2) { struct signalfd_siginfo info; ssize_t bytes; @@ -406,10 +294,13 @@ static void dooutput(struct script_control *ctl) assert(bytes == sizeof(info)); switch (info.ssi_signo) { case SIGCHLD: - done(ctl); + finish(ctl, 0); break; case SIGWINCH: - /* nothing */ + if (ctl->isterm) { + ioctl(STDIN_FILENO, TIOCGWINSZ, (char *)&ctl->win); + ioctl(ctl->slave, TIOCSWINSZ, (char *)&ctl->win); + } break; default: abort(); @@ -417,7 +308,9 @@ static void dooutput(struct script_control *ctl) } } } - abort(); + if (!ctl->die) + finish(ctl, 1); /* wait for children */ + done(ctl); } static void getslave(struct script_control *ctl) @@ -680,20 +573,9 @@ int main(int argc, char **argv) warn(_("fork failed")); fail(&ctl); } - if (ctl.child == 0) { - - ctl.subchild = ctl.child = fork(); - - if (ctl.child < 0) { - warn(_("fork failed")); - fail(&ctl); - } - if (ctl.child) - dooutput(&ctl); - else - doshell(&ctl); - } - doinput(&ctl); + if (ctl.child == 0) + doshell(&ctl); + do_io(&ctl); return EXIT_SUCCESS; } -- 2.2.1 -- To unsubscribe from this list: send the line "unsubscribe util-linux" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
