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35 changes: 17 additions & 18 deletions kyototycoon/kttimeddb.cc
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Original file line number Diff line number Diff line change
Expand Up @@ -112,33 +112,28 @@ bool TimedDB::dump_snapshot_atomic(const std::string& dest, kc::Compressor* zcom
db_.occupy(true, &forker);
cpid = forker.cpid();
};
if (cpid > 0) {
if (cpid == 0) {
// if there's a hang while writing the snapshot
// (defined as 2.8 hours going by without the file size changing)
// then abort with the "hanging" error
int64_t osiz = 0;
int32_t cnt = 0;
while (true) {
cnt++;
int32_t status;
int32_t rv = wait_impl(cpid, &status, 1);
if (rv == 0) return status == 0;
if (rv < 0) {
kill_impl(cpid, true);
wait_impl(cpid, &status, 1);
break;
}
pid_t parent_id = ::getppid();
for (int32_t cnt = 0; cnt < 100000; ++cnt) {
kc::Thread::sleep(0.1);

int64_t nsiz = 0;
kc::File::Status sbuf;
if (kc::File::status(dest, &sbuf)) nsiz = sbuf.size;
if (nsiz > osiz) {
osiz = nsiz;
cnt = 0;
}
if (cnt >= 10) {
db_.set_error(_KCCODELINE_, kc::BasicDB::Error::LOGIC, "hanging");
kill_impl(cpid, true);
wait_impl(cpid, &status, 0);
break;
}
}
db_.set_error(_KCCODELINE_, kc::BasicDB::Error::LOGIC, "hanging");
kill_impl(parent_id, true);
int32_t status;
wait_impl(parent_id, &status, 0);
return false;
} else if (cpid == 0) {
nice_impl(1);
Expand Down Expand Up @@ -232,7 +227,11 @@ bool TimedDB::dump_snapshot_atomic(const std::string& dest, kc::Compressor* zcom
if (cpid != 0) db_.set_error(_KCCODELINE_, kc::BasicDB::Error::SYSTEM, file.error());
return false;
}
if (cpid == 0) exit_impl(0);
if (cpid > 0) {
kill_impl(cpid, true);
int32_t status;
wait_impl(cpid, &status, 0);
}
return !err;
}

Expand Down