| -rw-r--r-- | src/process.cc | 30 |
1 files changed, 16 insertions, 14 deletions
diff --git a/src/process.cc b/src/process.cc index bfab311..1ffac9f 100644 --- a/src/process.cc +++ b/src/process.cc @@ -1,187 +1,189 @@ #include <stdio.h> #include <sys/types.h> #include <unistd.h> #include <signal.h> #include <pwd.h> #include <grp.h> #include <sys/wait.h> #include <syslog.h> #include <errno.h> #include <iostream> #include <fstream> #include <stdexcept> using namespace std; #include "process.h" #include "configuration.h" void process::check(const string& id,configuration& config) { - bool running = false; - ifstream pids(pidfile.c_str(),ios::in); - if(pids) { - pid_t pid = 0; - pids >> pid; - pids.close(); - if(pid) { - if(!kill(pid,0)) { - running = true; - } - } - } - if(running){ + try { + signal(0); patience = 0; - }else{ + }catch(exception& e) { if(patience>60) { // TODO: configurable patience = 0; }else{ if(patience<10) { // TODO: configurable syslog(LOG_NOTICE,"The process '%s' is down, trying to launch.",id.c_str()); do_notify(id,"Starting up", "The named process seems to be down. Dudki will try\n" "to revive it by running the specified command.\n", config); try { launch(id,config); }catch(exception& e) { syslog(LOG_ERR,"Error trying to launch process '%s': %s",id.c_str(),e.what()); } }else if(patience==10){ // TODO: configurable like the above syslog(LOG_NOTICE,"Giving up on process '%s' for a while",id.c_str()); do_notify(id,"Giving up", "After a number of attempts to relaunch the named process\n" "It still seems to be down. Dudki is giving up attempts\n" "to revive the process for a while.\n", config); } patience++; } } } void process::launch(const string& id,configuration& config) { uid_t uid = (uid_t)-1; gid_t gid = (gid_t)-1; if(!user.empty()) { struct passwd *ptmp = getpwnam(user.c_str()); if(ptmp) { uid = ptmp->pw_uid; gid = ptmp->pw_gid; }else{ errno=0; uid = strtol(user.c_str(),NULL,0); if(errno) throw runtime_error("Failed to resolve User value to uid"); } } if(!group.empty()) { struct group *gtmp = getgrnam(group.c_str()); if(gtmp) { gid = gtmp->gr_gid; }else{ errno = 0; gid = strtol(group.c_str(),NULL,0); if(errno) throw runtime_error("Failed to reslove Group value to gid"); } } pid_t p = fork(); if(p<0) throw runtime_error(string(__PRETTY_FUNCTION__)+": failed to fork()"); if(!p) { // child try { setsid(); if(user.empty()) { if((getgid()!=gid) && setgid(gid)) throw runtime_error(string(__PRETTY_FUNCTION__)+": failed to setgid()"); }else{ if(initgroups(user.c_str(),gid)) throw runtime_error(string(__PRETTY_FUNCTION__)+": failed to initgroups()"); } if(!chroot.empty()) { if(::chroot(chroot.c_str())) throw runtime_error(string(__PRETTY_FUNCTION__)+": failed to chroot()"); } if(!user.empty()) { if((getuid()!=uid) && setuid(uid)) throw runtime_error(string(__PRETTY_FUNCTION__)+": failed to setuid()"); } char *argv[] = { "/bin/sh", "-c", (char*)restart_cmd.c_str(), NULL }; close(0); close(1); close(2); execv("/bin/sh",argv); }catch(exception& e) { syslog(LOG_ERR,"Error trying to launch process '%s': %s",id.c_str(),e.what()); } _exit(-1); } // parent int rv; if(waitpid(p,&rv,0)<0) throw runtime_error(string(__PRETTY_FUNCTION__)+": failed to waitpid()"); } void process::do_notify(const string& id,const string& event,const string& description,configuration& config) { string the_notify; if(!notify.empty()) the_notify=notify; else if(!config.notify.empty()) the_notify=config.notify; else return; try { string::size_type colon = the_notify.find(':'); if(colon==string::npos) throw runtime_error("invalid notify action specification"); string nschema = the_notify.substr(0,colon); string ntarget = the_notify.substr(colon+1); if(nschema=="mailto") { notify_mailto(ntarget,id,event,description,config); }else throw runtime_error("unrecognized notification schema"); }catch(exception& e) { syslog(LOG_ERR,"Notification error: %s",e.what()); } } void process::notify_mailto(const string& email,const string& id,const string& event,const string& description,configuration& config) { int files[2]; if(pipe(files)) throw runtime_error("Failed to pipe()"); pid_t pid = vfork(); if(pid==-1) { close(files[0]); close(files[1]); throw runtime_error("Failed to vfork()"); } if(!pid) { // child if(dup2(files[0],0)!=0) _exit(-1); close(1); close(files[0]); close(files[1]); execl("/usr/sbin/sendmail","usr/sbin/sendmail","-i",email.c_str(),NULL); _exit(-1); } // parent close(files[0]); FILE *mta = fdopen(files[1],"w"); for(headers_t::const_iterator i=mailto_headers.begin();i!=mailto_headers.end();++i) { fprintf(mta,"%s: %s\n",i->first.c_str(),i->second.c_str()); } for(headers_t::const_iterator i=config.mailto_headers.begin();i!=config.mailto_headers.end();++i) { if(mailto_headers.find(i->first)!=mailto_headers.end()) continue; fprintf(mta,"%s: %s\n",i->first.c_str(),i->second.c_str()); } fprintf(mta, "Subject: [%s] %s\n\n" "%s\n" "---\n" "This message was sent automatically by the 'dudki' daemon\n", id.c_str(), event.c_str(), description.c_str() ); fclose(mta); int status; waitpid(pid,&status,0); // TODO: check the return code } + +void process::signal(int signum) const { + ifstream pids(pidfile.c_str(),ios::in); + if(!pids) + throw runtime_error("no pidfile found"); + pid_t pid = 0; + pids >> pid; + pids.close(); + if(!pid) + throw runtime_error("no pid in pidfile"); + if(kill(pid,signum)) + throw runtime_error("failed to signal process"); +} |