diff --git a/git.c b/git.c index 9c49519831..bf4d41f0e6 100644 --- a/git.c +++ b/git.c @@ -592,6 +592,26 @@ static int run_argv(int *argcp, const char ***argv) return done_alias; } +/* + * Many parts of Git have subprograms communicate via pipe, expect the + * upstream of a pipe to die with SIGPIPE when the downstream of a + * pipe does not need to read all that is written. Some third-party + * programs that ignore or block SIGPIPE for their own reason forget + * to restore SIGPIPE handling to the default before spawning Git and + * break this carefully orchestrated machinery. + * + * Restore the way SIGPIPE is handled to default, which is what we + * expect. + */ +static void restore_sigpipe_to_default(void) +{ + sigset_t unblock; + + sigemptyset(&unblock); + sigaddset(&unblock, SIGPIPE); + sigprocmask(SIG_UNBLOCK, &unblock, NULL); + signal(SIGPIPE, SIG_DFL); +} int main(int argc, char **av) { @@ -611,6 +631,8 @@ int main(int argc, char **av) */ sanitize_stdfds(); + restore_sigpipe_to_default(); + git_setup_gettext(); trace_command_performance(argv); diff --git a/t/t0005-signals.sh b/t/t0005-signals.sh index 981437b3a8..638a355906 100755 --- a/t/t0005-signals.sh +++ b/t/t0005-signals.sh @@ -27,4 +27,26 @@ test_expect_success !MINGW 'signals are propagated using shell convention' ' test_expect_code 143 git sigterm ' +large_git () { + for i in $(test_seq 1 100) + do + git diff --cached --binary || return + done +} + +test_expect_success 'create blob' ' + test-genrandom foo 16384 >file && + git add file +' + +test_expect_success 'a constipated git dies with SIGPIPE' ' + OUT=$( ((large_git; echo $? 1>&3) | :) 3>&1 ) + test "$OUT" -eq 141 +' + +test_expect_success 'a constipated git dies with SIGPIPE even if parent ignores it' ' + OUT=$( ((trap "" PIPE; large_git; echo $? 1>&3) | :) 3>&1 ) + test "$OUT" -eq 141 +' + test_done