| -rw-r--r-- | src/process.cc | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/src/process.cc b/src/process.cc index 6d3b2a2..4807b98 100644 --- a/src/process.cc +++ b/src/process.cc @@ -1,297 +1,302 @@ #include <stdio.h> #include <sys/types.h> #include <unistd.h> #include <signal.h> #include <pwd.h> #include <grp.h> #include <dirent.h> #include <sys/wait.h> #include <syslog.h> #include <errno.h> #include <iostream> #include <fstream> #include <sstream> #include <stdexcept> #include <string> #include <vector> using namespace std; #include "process.h" #include "configuration.h" static multimap<string,pid_t> procpids; void process::check() const { if(!pidfile.empty()) { signal(0); }else if(!process_name.empty()) { if(procpids.empty()) gather_proc_info(); if(procpids.find(process_name)==procpids.end()) throw runtime_error("no such process"); } // XXX: or else? } void process::check(const string& id,configuration& config) { try { check(); patience = 0; }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(!group.empty()) { 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 + int status; + if(waitpid(pid,&status,WNOHANG)) { + close(files[0]); + close(files[1]); + throw runtime_error("vfork()ed sendmail child exited unexpectedly"); + } 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 { if(!pidfile.empty()) { 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"); }else if(!process_name.empty()) { if(procpids.empty()) gather_proc_info(); pair<multimap<string,pid_t>::const_iterator,multimap<string,pid_t>::const_iterator> range = procpids.equal_range(process_name); int count = 0; for(multimap<string,pid_t>::const_iterator i=range.first;i!=range.second;++i) { pid_t pid = i->second; if(kill(i->second,signum)) throw runtime_error("failed to signal process"); count++; } if(!count) throw runtime_error("no running instance detected"); }else throw runtime_error("nothing is known about the process"); } void process::prepare_herd() { procpids.clear(); } void process::unprepare_herd() { procpids.clear(); } void process::gather_proc_info() { vector<pid_t> allpids; DIR *pd = opendir("/proc"); if(!pd) throw runtime_error("failed to open /proc"); struct dirent *pde; pid_t selfpid = getpid(); while(pde=readdir(pd)) { errno=0; pid_t pid = atoi(pde->d_name); if((!pid) || pid==selfpid) continue; allpids.push_back(pid); } closedir(pd); char s[256]; procpids.clear(); for(vector<pid_t>::const_iterator i=allpids.begin();i!=allpids.end();++i) { int r = snprintf(s,sizeof(s),"/proc/%d/stat",*i); if(r>=sizeof(s) || r<1) continue; string cmd; ifstream ss(s,ios::in); if(ss) { getline(ss,cmd); string::size_type op = cmd.find('('); if(op==string::npos) continue; cmd.erase(0,op+1); string::size_type cp = cmd.find(')'); if(cp==string::npos) continue; cmd.erase(cp); }else{ r = snprintf(s,sizeof(s),"/proc/%d/status",*i); if(r>=sizeof(s) || r<1) continue; ifstream ss(s,ios::in); if(!ss) continue; ss >> cmd; if(cmd.empty()) continue; } r = snprintf(s,sizeof(s),"/proc/%d/cmdline",*i); if(r>=sizeof(s) || r<1) continue; ifstream cs(s,ios::binary); if(!cs) continue; string command; while(cs) { string cl; getline(cs,cl,(char)0); string::size_type lsl = cl.rfind('/'); if(lsl!=string::npos) cl.erase(0,lsl+1); if(cl.substr(0,cmd.length())==cmd) { command = cl; break; } } procpids.insert(pair<string,pid_t>(cmd,*i)); if((!command.empty()) && cmd!=command) procpids.insert(pair<string,pid_t>(command,*i)); } } |