void LoggerImpl::runLoggerProcess(const std::string& user, const std::string& group)
{
struct passwd * pw = 0;
if (!user.empty())
{
pw = getpwnam(user.c_str());
if (pw == 0)
throw std::runtime_error("unknown user \"" + user + "\" in logging configuration");
}
struct group * gr = 0;
if (!group.empty())
{
gr = getgrnam(group.c_str());
if (gr == 0)
throw std::runtime_error("unknown group \"" + group + "\" in logging configuration");
}
pipe = new posix::Pipestream();
pid_t pid = ::fork();
if(pid < 0)
throw SystemError("fork");
if (pid == 0)
{
// 1st child
pipe->closeWriteFd();
pid = ::fork();
if (pid < 0)
exit(-1);
if (pid)
exit(0); // exit middle process
// 2nd child
std::streambuf* in = pipe->rdbuf();
// set global pipe pointer to 0, so that getAppender do not return
// that pipe, but skips to the next appender
pipe = 0;
setUserAndGroup(pw, gr);
log_debug("logger process initialized");
char ich;
std::ostream& out = getAppender();
while ((ich = in->snextc()) != std::ios::traits_type::eof())
{
char ch = std::ios::traits_type::to_char_type(ich);
out.rdbuf()->sputc(ch);
if (ch == '\n')
getAppender().flush();
}
exit(0);
}
else
{
// parent
pipe->closeReadFd();
int status;
::waitpid(pid, &status, 0);
if (WEXITSTATUS(status) != 0)
throw std::runtime_error("error creating logging process");
}
}
Appender* Appender::getAppender( const char * pName )
{
return getAppender( pName, "appender.ps" );
}
