Prevent zombie processes (#8774)

Using Systemcall::startscript() with Starttype::DontWait used to create
zombie processes, as nobody would collect them. This patch starts those
processes as detached, hence preventing them from becoming zombies.

In addition to #8774, this bug was also reported here:
https://bugs.launchpad.net/ubuntu/+source/lyx/+bug/1096666

Patch from Guy Rutenberg. For reference, see this email thread:
http://www.mail-archive.com/lyx-devel@lists.lyx.org/msg180034.html
This commit is contained in:
Scott Kostyshak 2013-07-16 00:39:28 -04:00
parent 5b7152a455
commit 5225821242
3 changed files with 25 additions and 11 deletions

View File

@ -1475,6 +1475,14 @@ contributers = [
"25 September 2007",
u"Major rework of the AMS classes"),
contributer(u"Guy Rutenberg",
"guyrutenberg () gmail ! com",
"GPL",
"Re: [PATCH] Strange Behaivor: xdg-open left as zombie",
"m=137365070116624",
"12 July 2013",
u"System call fixes"),
contributer(u"Ran Rutenberg",
"ran.rutenberg () gmail ! com",
"GPL",

View File

@ -251,19 +251,17 @@ int Systemcall::startscript(Starttype how, string const & what,
SystemcallPrivate d(infile, outfile, errfile);
d.startProcess(cmd, path);
if (!d.waitWhile(SystemcallPrivate::Starting, process_events, -1)) {
d.startProcess(cmd, path, how == DontWait);
if (how == DontWait && d.state == SystemcallPrivate::Running) {
return 0;
}
if (d.state == SystemcallPrivate::Error
|| !d.waitWhile(SystemcallPrivate::Starting, process_events, -1)) {
LYXERR0("Systemcall: '" << cmd << "' did not start!");
LYXERR0("error " << d.errorMessage());
return 10;
}
if (how == DontWait) {
QProcess* released = d.releaseProcess();
(void) released; // TODO who deletes it?
return 0;
}
if (!d.waitWhile(SystemcallPrivate::Running, process_events,
os::timeout_min() * 60 * 1000)) {
LYXERR0("Systemcall: '" << cmd << "' did not finish!");
@ -349,10 +347,18 @@ SystemcallPrivate::SystemcallPrivate(std::string const & sf,
}
void SystemcallPrivate::startProcess(QString const & cmd, string const & path)
void SystemcallPrivate::startProcess(QString const & cmd, string const & path, bool detached)
{
cmd_ = cmd;
if (process_) {
if (detached) {
state = SystemcallPrivate::Running;
if (!QProcess::startDetached(toqstr(latexEnvCmdPrefix(path)) + cmd_)) {
state = SystemcallPrivate::Error;
return;
}
QProcess* released = releaseProcess();
delete released;
} else if (process_) {
state = SystemcallPrivate::Starting;
process_->start(toqstr(latexEnvCmdPrefix(path)) + cmd_);
}

View File

@ -45,7 +45,7 @@ public:
State state;
bool waitWhile(State, bool processEvents, int timeout = -1);
void startProcess(QString const & cmd, std::string const & path);
void startProcess(QString const & cmd, std::string const & path, bool detach);
int exitCode();