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| author | Sami Kerola | 2014-12-26 18:43:49 +0100 |
|---|---|---|
| committer | Sami Kerola | 2015-06-08 22:52:51 +0200 |
| commit | 89a859d433fbba81cd70ba5e42fc86e971233dce (patch) | |
| tree | 400c4477517f9e55442054f372773d68ee7fb20c /term-utils/script.c | |
| parent | script: merge doinput() and output() functions to do_io() (diff) | |
| download | kernel-qcow2-util-linux-89a859d433fbba81cd70ba5e42fc86e971233dce.tar.gz kernel-qcow2-util-linux-89a859d433fbba81cd70ba5e42fc86e971233dce.tar.xz kernel-qcow2-util-linux-89a859d433fbba81cd70ba5e42fc86e971233dce.zip | |
script: remove io vs signal race
Make do_io() to run poll() until all streams are empty. This should
remove the signal from child versus io handling race for good.
Addresses: https://github.com/karelzak/util-linux/pull/62
Addresses: https://bugs.launchpad.net/bugs/264967
Addresses: https://bugs.debian.org/305808
CC: Wolfgang Richter <wolf@cs.cmu.edu>
CC: Ruediger Meier <ruediger.meier@ga-group.nl>
Signed-off-by: Sami Kerola <kerolasa@iki.fi>
Diffstat (limited to 'term-utils/script.c')
| -rw-r--r-- | term-utils/script.c | 20 |
1 files changed, 13 insertions, 7 deletions
diff --git a/term-utils/script.c b/term-utils/script.c index ea776cf72..391aa9e5e 100644 --- a/term-utils/script.c +++ b/term-utils/script.c @@ -92,6 +92,7 @@ struct script_control { FILE *timingfp; /* timing file pointer */ int master; /* pseudoterminal master file descriptor */ int slave; /* pseudoterminal slave file descriptor */ + int poll_timeout; /* poll() timeout, used in end of execution */ pid_t child; /* child pid */ int childstatus; /* child process exit value */ struct termios tt; /* slave terminal runtime attributes */ @@ -205,16 +206,11 @@ static void finish(struct script_control *ctl, int wait) { int status; pid_t pid; - int errsv = errno; int options = wait ? 0 : WNOHANG; while ((pid = wait3(&status, options, 0)) > 0) - if (pid == ctl->child) { + if (pid == ctl->child) ctl->childstatus = status; - ctl->die = 1; - } - - errno = errsv; } static void write_output(struct script_control *ctl, char *obuf, @@ -270,13 +266,15 @@ static void do_io(struct script_control *ctl) while (!ctl->die) { /* wait for input or signal */ - ret = poll(pfd, POLLFDS, -1); + ret = poll(pfd, POLLFDS, ctl->poll_timeout); if (ret < 0) { if (errno == EAGAIN) continue; warn(_("poll failed")); fail(ctl); } + if (ret == 0) + ctl->die = 1; for (i = 0; i < POLLFDS; i++) { if (pfd[i].revents == 0) continue; @@ -315,6 +313,13 @@ static void do_io(struct script_control *ctl) switch (info.ssi_signo) { case SIGCHLD: finish(ctl, 0); + ctl->poll_timeout = 10; + if (!ctl->isterm) + /* In situation such as 'date' in + * $ echo date | ./script + * ignore input when shell has + * exited. */ + pfd[0].fd = -1; break; case SIGWINCH: if (ctl->isterm) { @@ -496,6 +501,7 @@ int main(int argc, char **argv) .line = "/dev/ptyXX", #endif .master = -1, + .poll_timeout = -1, 0 }; int ch; |