git.m6w6.name Git - m6w6/libmemcached/blob - util/pidfile.cc

   1 /*  vim:expandtab:shiftwidth=2:tabstop=2:smarttab:
   2  *
   3  *  DataDifferential Utility Library
   4  *
   5  *  Copyright (C) 2011 Data Differential, http://datadifferential.com/
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  37
  38 #include "config.h"
  39
  40 #include "util/pidfile.hpp"
  41
  42 #include <cstdio>
  43 #include <cstdlib>
  44 #include <cstring>
  45 #include <errno.h>
  46 #include <fcntl.h>
  47 #include <iostream>
  48 #include <sys/stat.h>
  49 #include <sys/types.h>
  50
  51 namespace datadifferential {
  52 namespace util {
  53
  54 Pidfile::Pidfile(const std::string &arg) :
  55   _last_errno(0),
  56   _filename(arg)
  57 {
  58 }
  59
  60
  61 Pidfile::~Pidfile()
  62 {
  63   if (not _filename.empty() and (unlink(_filename.c_str()) == -1))
  64   {
  65     _error_message+= "Could not remove the pid file: ";
  66     _error_message+= _filename;
  67   }
  68 }
  69
  70 bool Pidfile::create()
  71 {
  72   if (_filename.empty())
  73     return true;
  74
  75   int file;
  76   if ((file = open(_filename.c_str(), O_CREAT|O_WRONLY|O_TRUNC, S_IRWXU|S_IRGRP|S_IROTH)) < 0)
  77   {
  78     _error_message+= "Could not open pid file for writing: ";
  79     _error_message+= _filename;
  80     return false;
  81   }
  82
  83   char buffer[BUFSIZ];
  84
  85   unsigned long temp= static_cast<unsigned long>(getpid());
  86   int length= snprintf(buffer, sizeof(buffer), "%lu\n", temp);
  87
  88   if (write(file, buffer, length) != length)
  89   {
  90     _error_message+= "Could not write pid to file: ";
  91     _error_message+= _filename;
  92     close(file);
  93
  94     return false;
  95   }
  96
  97   if (close(file) < 0)
  98   {
  99     _error_message+= "Could not close() file after writing pid to it: ";
 100     _error_message+= _filename;
 101     return false;
 102   }
 103
 104   return true;
 105 }
 106
 107 } /* namespace util */
 108 } /* namespace datadifferential */