script: exit if reading from pseudo-tty errors out (do not loop)

function                                             old     new   delta
script_main                                          991     966     -25
This commit is contained in:
Denis Vlasenko 2008-05-06 19:11:41 +00:00
parent dddfaff363
commit 06ebc16461

View File

@ -99,13 +99,12 @@ int script_main(int argc ATTRIBUTE_UNUSED, char **argv)
/* parent */
#define buf bb_common_bufsiz1
struct pollfd pfd[2];
struct pollfd *ppfd = pfd;
int outfd, count, loop;
outfd = xopen(fname, mode);
pfd[0].fd = 0;
pfd[0].fd = pty;
pfd[0].events = POLLIN;
pfd[1].fd = pty;
pfd[1].fd = 0;
pfd[1].events = POLLIN;
ndelay_on(pty); /* this descriptor is not shared, can do this */
/* ndelay_on(0); - NO, stdin can be shared! Pity :( */
@ -115,29 +114,17 @@ int script_main(int argc ATTRIBUTE_UNUSED, char **argv)
/* TODO: don't use full_write's, use proper write buffering */
while (fd_count) {
/* not safe_poll! we want SIGCHLD to EINTR poll */
if (poll(ppfd, fd_count, -1) < 0 && errno != EINTR) {
if (poll(pfd, fd_count, -1) < 0 && errno != EINTR) {
/* If child exits too quickly, we may get EIO:
* for example, try "script -c true" */
break;
}
if (pfd[0].revents) {
count = safe_read(0, buf, sizeof(buf));
if (count <= 0) {
/* err/eof: don't read anymore */
pfd[0].revents = 0;
ppfd++;
fd_count--;
} else {
full_write(pty, buf, count);
}
}
if (pfd[1].revents) {
errno = 0;
count = safe_read(pty, buf, sizeof(buf));
if (count <= 0 && errno != EAGAIN) {
/* err/eof: don't read anymore */
pfd[1].revents = 0;
fd_count--;
/* err/eof from pty: exit */
goto restore;
}
if (count > 0) {
full_write(1, buf, count);
@ -147,6 +134,16 @@ int script_main(int argc ATTRIBUTE_UNUSED, char **argv)
}
}
}
if (pfd[1].revents) {
count = safe_read(0, buf, sizeof(buf));
if (count <= 0) {
/* err/eof from stdin: don't read stdin anymore */
pfd[1].revents = 0;
fd_count--;
} else {
full_write(pty, buf, count);
}
}
}
/* If loop was exited because SIGCHLD handler set fd_count to 0,
* there still can be some buffered output. But not loop forever:
@ -161,7 +158,7 @@ int script_main(int argc ATTRIBUTE_UNUSED, char **argv)
full_write(1, buf, count);
full_write(outfd, buf, count);
}
restore:
if (attr_ok == 0)
tcsetattr(0, TCSAFLUSH, &tt);
if (!(opt & 8)) /* not -q */