processes specified by process names (pidof-like).

6 files changed, 131 insertions, 14 deletions

diff --git a/NEWS.xml b/NEWS.xml
index cd12d05..cc6085d 100644
--- a/NEWS.xml
+++ b/NEWS.xml
@@ -1,14 +1,15 @@
 <?xml version="1.0" encoding="us-ascii"?>
 <news>
- <version version="0.2" date="July 23rd, 2004">
+ <version version="0.2" date="July 24th, 2004">
   <ni>now dudki sends arbitrary signals to the processes being monitored from the command line</ni>
+  <ni>detection of running processes which do not keep pidfiles, using process name</ni>
  </version>
  <version version="0.1" date="July 21st, 2004">
   <ni><kbd>initgroups()</kbd> called before executing <kbd>RestartCommand</kbd></ni>
   <ni>more civilized way of restarting on <kbd>SIGHUP</kbd></ni>
   <ni>minor changes to build process</ni>
  </version>
  <version version="0.0" date="July 11th, 2004">
   <ni>Initial release</ni>
  </version>
 </news>
diff --git a/man/dudki.conf.5.in b/man/dudki.conf.5.in
index 23f636d..7d365d3 100644
--- a/man/dudki.conf.5.in
+++ b/man/dudki.conf.5.in
@@ -1,154 +1,158 @@
-.TH dudki.conf 5 "July 9th, 2004" "dudki.conf(5)" "Klever Group (http://www.klever.net/)"
+.TH dudki.conf 5 "July 24th, 2004" "dudki.conf(5)" "Klever Group (http://www.klever.net/)"
 .hla en
 
 .SH NAME
 
 dudki.conf \- The configuration file for the dudki process
 monitoring daemon
 
 .SH SYNOPSIS
 
 The dudki.conf file is a runtime configuration file for the dudki
 process monitoring daemon. It contains the information about the process
 being monitored and the instruction on how to cope with the processes.
 
 .SH FILE FORMAT
 
 The file consist of the global configuration and per-process
 configuration sections. The global configuration controls general
 dudki behaviour and sets defaults for per-process configuration
 directives.
 
 .SH GLOBAL CONFIGURATION
 
 .TP
 \fBCheckInterval\fR \fIseconds\fR
 Specifies interval in seconds at wich dudki performs checks.
 .TP
 \fBDaemonize\fR \fIon/off\fR
 Specifies whether dudki daemon should fork itself into background.
 Normally, you don't want it to run in foreground. Unless you want to run
 it from \fIinit(8)\fR process (I've nevetr tried it) via
 \fIinittab(5)\fR.
 .TP
 \fBPidFile\fR \fIfilename\fR
 Specifies where to store dudki's process id (default is
 /var/run/dudki.pid)
 .TP
 \fBMailtoHeader\fR \fIheader\fR \fIcontent\fR
 Sets global defaults for process section's MailtoHeader directive. See
 below.
 .TP
 \fBNotify\fR \fIschema\fR:\fItarget\fR
 Sets global default for per process notification. See below.
 
 .TP
 \fB<Process\fR \fIidentifier\fR\fB>\fR
 Starts per process configuration section. The process will be referenced
 using the short descriptive name specified (for example in email
 notifications).
 
 .SH PER-PROCESS CONFIGURATION
 
 Per-process configuration sections specifies the processes to monitor.
 And parameters pertaining to the process.
 
 .TP
 \fBPidFile\fR \fIfilename\fR
 Specifies the file where to fetch process id of the process being
 monitored from. The absence of file, as well as the absence of process
 specified by the pid stored in the file signifies the process death and
 triggers restart.
 .TP
+\fBProcessName\fR \fIprocess name\fR
+Specifies the name of the process. The alternative way to find process if it
+doesn't keep pid in the file. Similar to \fBpidof\fR(1).
+.TP
 \fBRestartCommand\fR \fIcommand\fR
 Specifies the command to run in order to restart the process.
 .TP
 \fBUser\fR \fIuser\fR
 Specifies the unix user to change to before executing the command
 specified by \fBRestartCommand\fR.
 .TP
 \fBGroup\fR \fIgroup\fR
 Specifies the unix group to change to before executing the command
 specified by \fBRestartCommand\fR.
 .TP
 \fBChroot\fR \fIpath\fR
 Specifies the directory to set filesystem root to before executing the
 command specified by by \fBRestartCommand\fR.
 .TP
 \fBMailtoHeader\fR \fIheader\fR \fIcontent\fR
 Specifies extra headers to add to mailto: notifications sent by the
 dudki daemon. Headers specified in per-process section override the
 ones specified globally.A
 .TP
 \fBNotify\fR \fIschema\fR:\fItarget\fR
 Specifies the contact to be notified whenever something notable happens
 to the process. The only schema currently supported is 'mailto:'.
 .TP
 \fB</Process>\fR
 Signifies the end of process section.
 
 .SH EXAMPLE
 
 .br
 CheckInterval 60
 .br
 PidFile /var/run/dudki.pid
 .br
 Daemonize on
 .br
 MailtoHeader From "Dudki <root@klever.net>"
 .br
 MailtoHeader Reply-To devnull@klever.net
 .br
 Notify mailto:hacker@klever.net
 .br 
 
 .br
 <Process apache>
 .br
  PidFile /var/run/httpd.pid
 .br
  RestartCommand "exec /usr/sbin/apachectl start"
 .br
 </Process>
 .br
 <Process named>
 .br
  PidFile /var/run/named.pid
 .br
  RestartCommand "exec /usr/sbin/named"
 .br
 </Process>
 
 .SH AUTHOR
 
 Written by Michael 'hacker' Krelin <hacker@klever.net>
 
 .SH COPYRIGHT
 
 Copyright (c) 2004 Klever Group (http://www.klever.net/)
 
 Permission is hereby granted, free of charge, to any person obtaining a copy of
 this software and associated documentation files (the "Software"), to deal in
 the Software without restriction, including without limitation the rights to
 use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
 of the Software, and to permit persons to whom the Software is furnished to do
 so, subject to the following conditions:
 
 The above copyright notice and this permission notice shall be included in all
 copies or substantial portions of the Software.
 
 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 SOFTWARE.
 
 .SH BUGS
 
 You tell me. Send reports to <dudki-bugs@klever.net>
 
 .SH SEE ALSO
 \fBdudki\fR(8), \fBinit\fR(8), \fBinittab\fR(5)
diff --git a/src/configuration.cc b/src/configuration.cc
index eb010c1..edc8c04 100644
--- a/src/configuration.cc
+++ b/src/configuration.cc
@@ -1,149 +1,154 @@
 #include <stdexcept>
 using namespace std;
 #include <dotconf.h>
 #include "configuration.h"
 
 #ifndef DEFAULT_PID_FILE
 # define DEFAULT_PID_FILE "/var/run/dudki.pid"
 #endif
 
 configuration::configuration()
     : check_interval(60), pidfile(DEFAULT_PID_FILE),
     daemonize(true) {
     }
 
 enum dc_ctx {
     DCC_ROOT = 1,
     DCC_PROCESS = 2
 };
 struct dc_context {
     dc_ctx ctx;
     configuration* cf;
     process* ps;
 
     dc_context()
         : ctx(DCC_ROOT), cf(NULL), ps(NULL) { }
 };
 
 static DOTCONF_CB(dco_check_interval) { dc_context *dcc = (dc_context*)ctx;
     dcc->cf->check_interval = cmd->data.value;
     return NULL;
 }
 static DOTCONF_CB(dco_daemonize) { dc_context *dcc = (dc_context*)ctx;
     dcc->cf->daemonize = cmd->data.value;
     return NULL;
 }
 
 static DOTCONF_CB(dco_pid_file) { dc_context *dcc = (dc_context*)ctx;
     switch(dcc->ctx) {
         case DCC_ROOT:
             dcc->cf->pidfile = cmd->data.str;
             break;
         case DCC_PROCESS:
             dcc->ps->pidfile = cmd->data.str;
             break;
         default:
             return "Unexpected PidFile";
     }
     return NULL;
 }
 static DOTCONF_CB(dco_mailto_header) { dc_context *dcc = (dc_context*)ctx;
     if(cmd->arg_count!=2)
         return "Invalid number of arguments";
     string h = cmd->data.list[0];
     string v = cmd->data.list[1];
     switch(dcc->ctx) {
         case DCC_ROOT:
             dcc->cf->mailto_headers[h] = v;
             break;
         case DCC_PROCESS:
             dcc->ps->mailto_headers[h] = v;
             break;
         default:
             return "Unexpected MailtoHeader";
     }
     return NULL;
 }
 static DOTCONF_CB(dco_notify) { dc_context *dcc = (dc_context*)ctx;
     switch(dcc->ctx) {
         case DCC_ROOT:
             dcc->cf->notify = cmd->data.str;
             break;
         case DCC_PROCESS:
             dcc->ps->notify = cmd->data.str;
             break;
         default:
             return "Unexpected Notify";
     }
     return NULL;
 }
 
 static DOTCONF_CB(dco_process) { dc_context *dcc = (dc_context*)ctx;
     string id = cmd->data.str;
     if(id[id.length()-1]=='>')
         id.erase(id.length()-1);
     dcc->ps = &(dcc->cf->processes[id]);
     dcc->ctx = DCC_PROCESS;
     return NULL;
 }
 static DOTCONF_CB(dco__process) { dc_context *dcc = (dc_context*)ctx;
     dcc->ps = NULL;
     dcc->ctx = DCC_ROOT;
     return NULL;
 }
 
+static DOTCONF_CB(dco_process_name) { dc_context *dcc = (dc_context*)ctx;
+    dcc->ps->process_name = cmd->data.str;
+    return NULL;
+}
 static DOTCONF_CB(dco_restart_command) { dc_context *dcc = (dc_context*)ctx;
     dcc->ps->restart_cmd = cmd->data.str;
     return NULL;
 }
 static DOTCONF_CB(dco_user) { dc_context *dcc = (dc_context*)ctx;
     dcc->ps->user = cmd->data.str;
     return NULL;
 }
 static DOTCONF_CB(dco_group) { dc_context *dcc = (dc_context*)ctx;
     dcc->ps->group = cmd->data.str;
     return NULL;
 }
 static DOTCONF_CB(dco_chroot) { dc_context *dcc = (dc_context*)ctx;
     dcc->ps->chroot = cmd->data.str;
     return NULL;
 }
 
 static const configoption_t dc_options[] = {
     { "CheckInterval", ARG_INT, dco_check_interval, NULL, DCC_ROOT },
     { "Daemonize", ARG_TOGGLE, dco_daemonize, NULL, DCC_ROOT },
     { "PidFile", ARG_STR, dco_pid_file, NULL, DCC_ROOT|DCC_PROCESS },
     { "MailtoHeader", ARG_STR, dco_mailto_header, NULL, DCC_ROOT|DCC_PROCESS },
     { "Notify", ARG_STR, dco_notify, NULL, DCC_ROOT|DCC_PROCESS },
     { "<Process", ARG_STR, dco_process, NULL, DCC_ROOT },
+    {  "ProcessName", ARG_STR, dco_process_name, NULL, DCC_PROCESS },
     {  "RestartCommand", ARG_STR, dco_restart_command, NULL, DCC_PROCESS },
     {  "User", ARG_STR, dco_user, NULL, DCC_PROCESS },
     {  "Group", ARG_STR, dco_group, NULL, DCC_PROCESS },
     {  "Chroot", ARG_STR, dco_chroot, NULL, DCC_PROCESS },
     { "</Process>", ARG_NONE, dco__process, NULL, DCC_PROCESS },
     LAST_OPTION
 };
 
 static const char *dc_context_checker(command_t *cmd,unsigned long mask) {
     dc_context *dcc = (dc_context*)cmd->context;
     if( (mask==CTX_ALL) || ((mask&dcc->ctx)==dcc->ctx) )
         return NULL;
     return "misplaced option";
 }
 static FUNC_ERRORHANDLER(dc_error_handler) {
     throw runtime_error(string("error parsing config file: ")+msg);
 }
     
 void configuration::parse(const string& cfile) {
     struct dc_context dcc;
     dcc.cf = this;
     dcc.ctx = DCC_ROOT;
     configfile_t *cf = dotconf_create((char*)cfile.c_str(),dc_options,(context_t*)&dcc,CASE_INSENSITIVE);
     if(!cf)
         throw runtime_error(string(__PRETTY_FUNCTION__)+": failed to dotconf_create()");
     cf->errorhandler = (dotconf_errorhandler_t) dc_error_handler;
     cf->contextchecker = (dotconf_contextchecker_t) dc_context_checker;
     if(!dotconf_command_loop(cf))
         throw runtime_error(string(__PRETTY_FUNCTION__)+": failed to dotconf_command_loop()");
     dotconf_cleanup(cf);
 }
diff --git a/src/dudki.cc b/src/dudki.cc
index 9562079..c966695 100644
--- a/src/dudki.cc
+++ b/src/dudki.cc
@@ -1,287 +1,292 @@
 #include <unistd.h>
 #include <signal.h>
 #include <syslog.h>
 #include <errno.h>
 #include <iostream>
 #include <fstream>
 #include <stdexcept>
 using namespace std;
 #include "configuration.h"
 #include "util.h"
 
 #include "config.h"
 #ifdef HAVE_GETOPT_H
 # include <getopt.h>
 #endif
 
 #ifndef DEFAULT_CONF_FILE
 # define DEFAULT_CONF_FILE "/etc/dudki.conf"
 #endif
 
 #define PHEADER PACKAGE " Version " VERSION
 #define PCOPY   "Copyright (c) 2004 Klever Group"
 
 bool finishing = false;
 bool restarting = false;
 static char **_argv = NULL;
 
 static void lethal_signal_handler(int signum) {
     syslog(LOG_NOTICE,"Lethal signal received. Terminating.");
     finishing = true;
 }
 static void sighup_handler(int signum) {
     syslog(LOG_NOTICE,"SUGHUP received, reloading.");
     restarting = finishing = true;
 }
 
 void check_herd(configuration& config) {
+    process::prepare_herd();
     for(processes_t::iterator i=config.processes.begin();i!=config.processes.end();++i)
         i->second.check(i->first,config);
+    process::unprepare_herd();
 }
 
 void signal_self(const configuration& config,int signum) {
     ifstream pids(config.pidfile.c_str(),ios::in);
     if(!pids)
         throw runtime_error("Can't detect running instance");
     pid_t pid = 0;
     pids >> pid;
     if(!pid)
         throw runtime_error("Can't detect running instance");
     if(pid==getpid())
         throw 0;
     if(kill(pid,signum))
         throw runtime_error("Failed to signal running instance");
 }
 
 int main(int argc,char **argv) {
     try {
         _argv = new char*[argc+1];
         if(!_argv)
             throw runtime_error("memory allocation problem at the very start");
         memmove(_argv,argv,sizeof(*_argv)*(argc+1));
         string config_file = DEFAULT_CONF_FILE;
         enum {
             op_default,
             op_work,
             op_signal,
             op_ensure,
             op_test
         } op = op_default;
         int op_signum = 0;
         while(true) {
         #defineSHORTOPTSTRING "f:hVLrkcets:"
 #ifdef HAVE_GETOPT_LONG
             static struct option opts[] = {
                 { "help", no_argument, 0, 'h' },
                 { "usage", no_argument, 0, 'h' },
                 { "version", no_argument, 0, 'V' },
                 { "license", no_argument, 0, 'L' },
                 { "config", required_argument, 0, 'f' },
                 { "kill", no_argument, 0, 'k' },
                 { "reload", no_argument, 0, 'r' },
                 { "signal", required_argument, 0, 's' },
                 { "check", no_argument, 0, 'c' },
                 { "ensure", no_argument, 0, 'e' },
                 { "test", no_argument, 0, 't' },
                 { NULL, 0, 0, 0 }
             };
             int c = getopt_long(argc,argv,SHORTOPTSTRING,opts,NULL);
 #else /* !HAVE_GETOPT_LONG */
             int c = getopt(argc,argv,SHORTOPTSTRING);
 #endif /* /HAVE_GETOPT_LONG */
             if(c==-1)
                 break;
             switch(c) {
                 case 'h':
                     cerr << PHEADER << endl
                         << PCOPY << endl << endl
                         << " " << argv[0] << " [options] [processes]" << endl << endl <<
 #ifdef HAVE_GETOPT_LONG
                         " -h, --help\n"
                         " --usage         display this text\n"
                         " -V, --version   display version number\n"
                         " -L, --license   show license\n"
                         " -f filename, --config=filename\n"
                         "                 specify the configuration file to use\n"
                         "\n"
                         " -k, --kill      stop running instance (send SIGTERM)\n"
                         " -r, --reload    reload running instance (send SIGHUP)\n"
                         " -s signum, --signal=signum\n"
                         "                 send the specified signal to the running process\n"
                         " -c, --check     check if the process is running\n"
                         "     (the above commands operate on dudki itself if no\n"
                         "      process name has been specified)\n"
                         " -e, --ensure    ensure that dudki is running\n"
                         " -t, --test      test configuration file and exit"
 #else /* !HAVE_GETOPT_LONG */
                         " -h              display this text\n"
                         " -V              display version number\n"
                         " -L              show license\n"
                         " -f filename     specify the configuration file to use\n"
                         "\n"
                         " -k              stop running instance (send SIGTERM)\n"
                         " -r              reload running instance (send SIGHUP)\n"
                         " -s signum       send the specified signal to the running process\n"
                         " -c              check if the process is running\n"
                         "     (the above commands operate on dudki itself if no\n"
                         "      process name has been specified)\n"
                         " -e              ensure that dudki is running\n"
                         " -t              test configuration file and exit"
 #endif /* /HAVE_GETOPT_LONG */
                         << endl;
                     exit(0);
                     break;
                 case 'V':
                     cerr << VERSION << endl;
                     exit(0);
                     break;
                 case 'L':
                     extern const char *COPYING;
                     cerr << COPYING << endl;
                     exit(0);
                     break;
                 case 'f':
                     config_file = optarg;
                     break;
                 case 'k':
                     if(op!=op_default) {
                         cerr << "Can't obey two or more orders at once" << endl;
                         exit(1);
                     }
                     op = op_signal; op_signum = SIGTERM;
                     break;
                 case 'r':
                     if(op!=op_default) {
                         cerr << "Can't obey two or more orders at once" << endl;
                         exit(1);
                     }
                     op = op_signal; op_signum = SIGHUP;
                     break;
                 case 'c':
                     if(op!=op_default) {
                         cerr << "Can't obey two or more orders at once" << endl;
                         exit(1);
                     }
                     op = op_signal; op_signum = 0;
                     break;
                 case 'e':
                     if(op!=op_default) {
                         cerr << "Can't obey two or more orders at once" << endl;
                         exit(1);
                     }
                     op = op_ensure;
                     break;
                 case 't':
                     if(op!=op_default) {
                         cerr << "Can't obey two or more orders at once" << endl;
                         exit(1);
                     }
                     op = op_test;
                     break;
                 case 's':
                     if(op!=op_default) {
                         cerr << "Can't obey two or more orders at once" << endl;
                         exit(1);
                     }
                     op = op_signal;
                     errno = 0;
                     op_signum = strtol(optarg,NULL,0);
                     if(errno) {
                         cerr << "Can't obtain the signal value" << endl;
                         exit(1);
                     }
                     break;
                 default:
                     cerr << "Huh??" << endl;
                     exit(1);
                     break;
             }
         }
         const char *sid = *argv;
         const char *t;
         while(t = index(sid,'/')) {
             sid = t; sid++;
         }
         openlog(sid,LOG_CONS|LOG_PERROR|LOG_PID,LOG_DAEMON);
         configuration config;
         config.parse(config_file);
         switch(op) {
             case op_test:
                 cerr << "Configuration OK" << endl;
                 break;
             case op_signal:
                 try {
                     if(optind>=argc) {
                         signal_self(config,op_signum);
                     }else{
                         int failures = 0;
                         for(int narg=optind;narg<argc;narg++) {
                             try {
                                 processes_t::const_iterator i = config.processes.find(argv[narg]);
                                 if(i==config.processes.end())
                                     throw runtime_error("no such process configured");
-                                i->second.signal(op_signum);
+                                if(op_signum)
+                                    i->second.signal(op_signum);
+                                else
+                                    i->second.check();
                             }catch(exception& e) {
                                 cerr << "dudki(" << argv[narg] << "): " << e.what() << endl;
                                 failures++;
                             }
                         }
                         if(failures)
                             throw runtime_error("not all processes have been successfully signaled");
                     }
                     if(!op_signum)
                         exit(0);
                 }catch(exception& e) {
                     if(!op_signum)
                         exit(1);
                 }
             case op_ensure:
                 try {
                     signal_self(config,0);
                     break;
                 }catch(exception& e) {
                     syslog(LOG_NOTICE,"The dudki process is down, taking its place");
                     config.daemonize = true;
                 }catch(int zero) {
                     // we throw zero in case we're ensuring that this very process is running.
                     // we don't have to daemonize if we're daemonic.
                     config.daemonize = false;
                 }
             case op_default:
             case op_work:
                 {
                     if(config.daemonize) {
                         pid_t pf = fork();
                         if(pf<0)
                             throw runtime_error(string(__PRETTY_FUNCTION__)+": failed to fork()");
                         if(pf) {
                             _exit(0);
                         }
                     }
                     pid_file pidfile;
                     pidfile.set(config.pidfile);
                     signal(SIGINT,lethal_signal_handler);
                     signal(SIGABRT,lethal_signal_handler);
                     signal(SIGTERM,lethal_signal_handler);
                     signal(SIGHUP,sighup_handler);
                     sigset_t sset;
                     sigemptyset(&sset);
                     sigaddset(&sset,SIGINT); sigaddset(&sset,SIGABRT);
                     sigaddset(&sset,SIGTERM); sigaddset(&sset,SIGHUP);
                     sigprocmask(SIG_UNBLOCK,&sset,NULL);
                     while(!finishing) {
                         check_herd(config);
                         sleep(config.check_interval);
                     }
                     if(restarting)
                         execvp(_argv[0],_argv);
                 }
                 break;
             default:
                 throw runtime_error(string(__PRETTY_FUNCTION__)+": internal error");
         }
     }catch(exception& e) {
         cerr << "Oops: " << e.what() << endl;
         return 1;
     }
 }
diff --git a/src/process.cc b/src/process.cc
index 1ffac9f..8a5b5d2 100644
--- a/src/process.cc
+++ b/src/process.cc
@@ -1,189 +1,285 @@
 #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 {
-        signal(0);
+        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(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");
+    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)
+            continue;
+        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);
+        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));
+    }
 }
diff --git a/src/process.h b/src/process.h
index 27ee049..90b12d9 100644
--- a/src/process.h
+++ b/src/process.h
@@ -1,38 +1,44 @@
 #ifndef __PROCESS_H
 #define __PROCESS_H
 
 #include <string>
 #include <map>
 using namespace std;
 
 class configuration;
 
 typedef map<string,string> headers_t;
 
 class process {
     public:
         string pidfile;
+        string process_name;
         string restart_cmd;
         string notify;
         string user;
         string group;
         string chroot;
         headers_t mailto_headers;
 
         int patience;
 
         process()
             : patience(0) { }
 
         void check(const string& id,configuration& config);
         void launch(const string& id,configuration& config);
         void do_notify(const string& id,const string& event,const string& description,configuration& config);
         void notify_mailto(const string& email,const string& id,const string& event,
                 const string& description,configuration& config);
 
         void signal(int signum) const;
+        void check() const;
+
+        static void prepare_herd();
+        static void gather_proc_info();
+        static void unprepare_herd();
 };
 
 typedef map<string,process> processes_t;
 
 #endif /* __PROCESS_H */