smartd.cpp

/*
 * Home page of code is: http://smartmontools.sourceforge.net
 *
 * Copyright (C) 2002-10 Bruce Allen <smartmontools-support@lists.sourceforge.net>
 * Copyright (C) 2000    Michael Cornwell <cornwell@acm.org>
 * Copyright (C) 2008    Oliver Bock <brevilo@users.sourceforge.net>
 * Copyright (C) 2008-10 Christian Franke <smartmontools-support@lists.sourceforge.net>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2, or (at your option)
 * any later version.
 *
 * You should have received a copy of the GNU General Public License
 * (for example COPYING); If not, see <http://www.gnu.org/licenses/>.
 *
 * This code was originally developed as a Senior Thesis by Michael Cornwell
 * at the Concurrent Systems Laboratory (now part of the Storage Systems
 * Research Center), Jack Baskin School of Engineering, University of
 * California, Santa Cruz. http://ssrc.soe.ucsc.edu/
 *
 */

#ifndef _GNU_SOURCE
// TODO: Why is this define necessary?
#define _GNU_SOURCE
#endif

// unconditionally included files
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>   // umask
#include <signal.h>
#include <fcntl.h>
#include <string.h>
#include <syslog.h>
#include <stdarg.h>
#include <stdlib.h>
#include <errno.h>
#include <time.h>
#include <limits.h>
#include <getopt.h>

#include <stdexcept>
#include <string>
#include <vector>
#include <algorithm> // std::replace()

// see which system files to conditionally include
#include "config.h"

// conditionally included files
#ifndef _WIN32
#include <sys/wait.h>
#endif
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#ifdef HAVE_NETDB_H
#include <netdb.h>
#endif

#ifdef _WIN32
#ifdef _MSC_VER
#pragma warning(disable:4761) // "conversion supplied"
typedef unsigned short mode_t;
typedef int pid_t;
#endif
#include <io.h> // umask()
#include <process.h> // getpid()
#endif // _WIN32

#ifdef __CYGWIN__
// From <windows.h>:
// BOOL WINAPI FreeConsole(void);
extern "C" int __stdcall FreeConsole(void);
#include <io.h> // setmode()
#endif // __CYGWIN__

#ifdef HAVE_LIBCAP_NG
#include <cap-ng.h>
#endif // LIBCAP_NG

// locally included files
#include "int64.h"
#include "atacmds.h"
#include "dev_interface.h"
#include "extern.h"
#include "knowndrives.h"
#include "scsicmds.h"
#include "utility.h"

// This is for solaris, where signal() resets the handler to SIG_DFL
// after the first signal is caught.
#ifdef HAVE_SIGSET
#define SIGNALFN sigset
#else
#define SIGNALFN signal
#endif

#ifdef _WIN32
#include "hostname_win32.h" // gethost/domainname()
#define HAVE_GETHOSTNAME   1
#define HAVE_GETDOMAINNAME 1
// fork()/signal()/initd simulation for native Windows
#include "daemon_win32.h" // daemon_main/detach/signal()
#undef SIGNALFN
#define SIGNALFN  daemon_signal
#define strsignal daemon_strsignal
#define sleep     daemon_sleep
// SIGQUIT does not exist, CONTROL-Break signals SIGBREAK.
#define SIGQUIT SIGBREAK
#define SIGQUIT_KEYNAME "CONTROL-Break"
#else  // _WIN32
#ifdef __CYGWIN__
// 2x CONTROL-C simulates missing SIGQUIT via keyboard
#define SIGQUIT_KEYNAME "2x CONTROL-C"
#else // __CYGWIN__
#define SIGQUIT_KEYNAME "CONTROL-\\"
#endif // __CYGWIN__
#endif // _WIN32

#if defined (__SVR4) && defined (__sun)
extern "C" int getdomainname(char *, int); // no declaration in header files!
#endif

#define ARGUSED(x) ((void)(x))

const char * smartd_cpp_cvsid = "$Id$"
                                CONFIG_H_CVSID EXTERN_H_CVSID;

extern const char *reportbug;

extern unsigned char debugmode;

// smartd exit codes
#define EXIT_BADCMD    1   // command line did not parse
#define EXIT_BADCONF   2   // syntax error in config file
#define EXIT_STARTUP   3   // problem forking daemon
#define EXIT_PID       4   // problem creating pid file
#define EXIT_NOCONF    5   // config file does not exist
#define EXIT_READCONF  6   // config file exists but cannot be read

#define EXIT_NOMEM     8   // out of memory
#define EXIT_BADCODE   10  // internal error - should NEVER happen

#define EXIT_BADDEV    16  // we can't monitor this device
#define EXIT_NODEV     17  // no devices to monitor

#define EXIT_SIGNAL    254 // abort on signal

// command-line: how long to sleep between checks
#define CHECKTIME 1800
static int checktime=CHECKTIME;

// command-line: name of PID file (empty for no pid file)
static std::string pid_file;

// command-line: path prefix of persistent state file, empty if no persistence.
static std::string state_path_prefix
#ifdef SMARTMONTOOLS_SAVESTATES
          = SMARTMONTOOLS_SAVESTATES
#endif
                                    ;

// command-line: path prefix of attribute log file, empty if no logs.
static std::string attrlog_path_prefix
#ifdef SMARTMONTOOLS_ATTRIBUTELOG
          = SMARTMONTOOLS_ATTRIBUTELOG
#endif
                                    ;

// configuration file name
#define CONFIGFILENAME "smartd.conf"

#ifndef _WIN32
static const char *configfile = SMARTMONTOOLS_SYSCONFDIR "/" CONFIGFILENAME ;
#else
static const char *configfile = "./" CONFIGFILENAME ;
#endif
// configuration file "name" if read from stdin
static const char * const configfile_stdin = "<stdin>";
// path of alternate configuration file
static std::string configfile_alt;

// command-line: when should we exit?
static int quit=0;

// command-line; this is the default syslog(3) log facility to use.
static int facility=LOG_DAEMON;

#ifndef _WIN32
// command-line: fork into background?
static bool do_fork=true;
#endif

#ifdef HAVE_LIBCAP_NG
// command-line: enable capabilities?
static bool enable_capabilities = false;
#endif

// used for control of printing, passing arguments to atacmds.c
smartmonctrl *con=NULL;

// set to one if we catch a USR1 (check devices now)
volatile int caughtsigUSR1=0;

#ifdef _WIN32
// set to one if we catch a USR2 (toggle debug mode)
volatile int caughtsigUSR2=0;
#endif

// set to one if we catch a HUP (reload config file). In debug mode,
// set to two, if we catch INT (also reload config file).
volatile int caughtsigHUP=0;

// set to signal value if we catch INT, QUIT, or TERM
volatile int caughtsigEXIT=0;

// Attribute monitoring flags.
// See monitor_attr_flags below.
enum {
  MONITOR_IGN_FAILUSE = 0x01,
  MONITOR_IGNORE      = 0x02,
  MONITOR_RAW_PRINT   = 0x04,
  MONITOR_RAW         = 0x08,
  MONITOR_AS_CRIT     = 0x10,
  MONITOR_RAW_AS_CRIT = 0x20,
};

// Array of flags for each attribute.
class attribute_flags
{
public:
  attribute_flags()
    { memset(m_flags, 0, sizeof(m_flags)); }

  bool is_set(int id, unsigned char flag) const
    { return (0 < id && id < (int)sizeof(m_flags) && (m_flags[id] & flag)); }

  void set(int id, unsigned char flags)
    {
      if (0 < id && id < (int)sizeof(m_flags))
        m_flags[id] |= flags;
    }

private:
  unsigned char m_flags[256];
};


/// Configuration data for a device. Read from smartd.conf.
/// Supports copy & assignment and is compatible with STL containers.
struct dev_config
{
  int lineno;                             // Line number of entry in file
  std::string name;                       // Device name
  std::string dev_type;                   // Device type argument from -d directive, empty if none
  std::string state_file;                 // Path of the persistent state file, empty if none
  std::string attrlog_file;               // Path of the persistent attrlog file, empty if none
  bool smartcheck;                        // Check SMART status
  bool usagefailed;                       // Check for failed Usage Attributes
  bool prefail;                           // Track changes in Prefail Attributes
  bool usage;                             // Track changes in Usage Attributes
  bool selftest;                          // Monitor number of selftest errors
  bool errorlog;                          // Monitor number of ATA errors
  bool permissive;                        // Ignore failed SMART commands
  char autosave;                          // 1=disable, 2=enable Autosave Attributes
  char autoofflinetest;                   // 1=disable, 2=enable Auto Offline Test
  unsigned char fix_firmwarebug;          // FIX_*, see atacmds.h
  bool ignorepresets;                     // Ignore database of -v options
  bool showpresets;                       // Show database entry for this device
  bool removable;                         // Device may disappear (not be present)
  char powermode;                         // skip check, if disk in idle or standby mode
  bool powerquiet;                        // skip powermode 'skipping checks' message
  int powerskipmax;                       // how many times can be check skipped
  unsigned char tempdiff;                 // Track Temperature changes >= this limit
  unsigned char tempinfo, tempcrit;       // Track Temperatures >= these limits as LOG_INFO, LOG_CRIT+mail
  regular_expression test_regex;          // Regex for scheduled testing

  // Configuration of email warning messages
  std::string emailcmdline;               // script to execute, empty if no messages
  std::string emailaddress;               // email address, or empty
  unsigned char emailfreq;                // Emails once (1) daily (2) diminishing (3)
  bool emailtest;                         // Send test email?

  // ATA ONLY
  unsigned char curr_pending_id;          // ID of current pending sector count, 0 if none
  unsigned char offl_pending_id;          // ID of offline uncorrectable sector count, 0 if none
  bool curr_pending_incr, offl_pending_incr; // True if current/offline pending values increase
  bool curr_pending_set,  offl_pending_set;  // True if '-C', '-U' set in smartd.conf

  attribute_flags monitor_attr_flags;     // MONITOR_* flags for each attribute

  ata_vendor_attr_defs attribute_defs;    // -v options

  dev_config();
};

dev_config::dev_config()
: lineno(0),
  smartcheck(false),
  usagefailed(false),
  prefail(false),
  usage(false),
  selftest(false),
  errorlog(false),
  permissive(false),
  autosave(0),
  autoofflinetest(0),
  fix_firmwarebug(FIX_NOTSPECIFIED),
  ignorepresets(false),
  showpresets(false),
  removable(false),
  powermode(0),
  powerquiet(false),
  powerskipmax(0),
  tempdiff(0),
  tempinfo(0), tempcrit(0),
  emailfreq(0),
  emailtest(false),
  curr_pending_id(0), offl_pending_id(0),
  curr_pending_incr(false), offl_pending_incr(false),
  curr_pending_set(false),  offl_pending_set(false)
{
}


// Number of allowed mail message types
const int SMARTD_NMAIL = 13;
// Type for '-M test' mails (state not persistent)
const int MAILTYPE_TEST = 0;
// TODO: Add const or enum for all mail types.

struct mailinfo {
  int logged;// number of times an email has been sent
  time_t firstsent;// time first email was sent, as defined by time(2)
  time_t lastsent; // time last email was sent, as defined by time(2)

  mailinfo()
    : logged(0), firstsent(0), lastsent(0) { }
};

/// Persistent state data for a device.
struct persistent_dev_state
{
  unsigned char tempmin, tempmax;         // Min/Max Temperatures

  unsigned char selflogcount;             // total number of self-test errors
  unsigned short selfloghour;             // lifetime hours of last self-test error

  time_t scheduled_test_next_check;       // Time of next check for scheduled self-tests

  mailinfo maillog[SMARTD_NMAIL];         // log info on when mail sent

  // ATA ONLY
  int ataerrorcount;                      // Total number of ATA errors

  // Persistent part of ata_smart_values:
  struct ata_attribute {
    unsigned char id;
    unsigned char val;
    unsigned char worst; // Byte needed for 'raw64' attribute only.
    uint64_t raw;

    ata_attribute() : id(0), val(0), worst(0), raw(0) { }
  };
  ata_attribute ata_attributes[NUMBER_ATA_SMART_ATTRIBUTES];

  persistent_dev_state();
};

persistent_dev_state::persistent_dev_state()
: tempmin(0), tempmax(0),
  selflogcount(0),
  selfloghour(0),
  scheduled_test_next_check(0),
  ataerrorcount(0)
{
}

/// Non-persistent state data for a device.
struct temp_dev_state
{
  bool must_write;                        // true if persistent part should be written

  bool not_cap_offline;                   // true == not capable of offline testing
  bool not_cap_conveyance;
  bool not_cap_short;
  bool not_cap_long;
  bool not_cap_selective;

  unsigned char temperature;              // last recorded Temperature (in Celsius)
  time_t tempmin_delay;                   // time where Min Temperature tracking will start

  bool powermodefail;                     // true if power mode check failed
  int powerskipcnt;                       // Number of checks skipped due to idle or standby mode

  // SCSI ONLY
  unsigned char SmartPageSupported;       // has log sense IE page (0x2f)
  unsigned char TempPageSupported;        // has log sense temperature page (0xd)
  unsigned char SuppressReport;           // minimize nuisance reports
  unsigned char modese_len;               // mode sense/select cmd len: 0 (don't
                                          // know yet) 6 or 10

  // ATA ONLY
  uint64_t num_sectors;                   // Number of sectors (for selective self-test only)
  ata_smart_values smartval;              // SMART data
  ata_smart_thresholds_pvt smartthres;    // SMART thresholds

  temp_dev_state();
};

temp_dev_state::temp_dev_state()
: must_write(false),
  not_cap_offline(false),
  not_cap_conveyance(false),
  not_cap_short(false),
  not_cap_long(false),
  not_cap_selective(false),
  temperature(0),
  tempmin_delay(0),
  powermodefail(false),
  powerskipcnt(0),
  SmartPageSupported(false),
  TempPageSupported(false),
  SuppressReport(false),
  modese_len(0),
  num_sectors(0)
{
  memset(&smartval, 0, sizeof(smartval));
  memset(&smartthres, 0, sizeof(smartthres));
}

/// Runtime state data for a device.
struct dev_state
: public persistent_dev_state,
  public temp_dev_state
{
  void update_persistent_state();
  void update_temp_state();
};

/// Container for configuration info for each device.
typedef std::vector<dev_config> dev_config_vector;

/// Container for state info for each device.
typedef std::vector<dev_state> dev_state_vector;

// Copy ATA attributes to persistent state.
void dev_state::update_persistent_state()
{
  for (int i = 0; i < NUMBER_ATA_SMART_ATTRIBUTES; i++) {
    const ata_smart_attribute & ta = smartval.vendor_attributes[i];
    ata_attribute & pa = ata_attributes[i];
    pa.id = ta.id;
    if (ta.id == 0) {
      pa.val = pa.worst = 0; pa.raw = 0;
      continue;
    }
    pa.val = ta.current;
    pa.worst = ta.worst;
    pa.raw =            ta.raw[0]
           | (          ta.raw[1] <<  8)
           | (          ta.raw[2] << 16)
           | ((uint64_t)ta.raw[3] << 24)
           | ((uint64_t)ta.raw[4] << 32)
           | ((uint64_t)ta.raw[5] << 40);
  }
}

// Copy ATA from persistent to temp state.
void dev_state::update_temp_state()
{
  for (int i = 0; i < NUMBER_ATA_SMART_ATTRIBUTES; i++) {
    const ata_attribute & pa = ata_attributes[i];
    ata_smart_attribute & ta = smartval.vendor_attributes[i];
    ta.id = pa.id;
    if (pa.id == 0) {
      ta.current = ta.worst = 0;
      memset(ta.raw, 0, sizeof(ta.raw));
      continue;
    }
    ta.current = pa.val;
    ta.worst = pa.worst;
    ta.raw[0] = (unsigned char) pa.raw;
    ta.raw[1] = (unsigned char)(pa.raw >>  8);
    ta.raw[2] = (unsigned char)(pa.raw >> 16);
    ta.raw[3] = (unsigned char)(pa.raw >> 24);
    ta.raw[4] = (unsigned char)(pa.raw >> 32);
    ta.raw[5] = (unsigned char)(pa.raw >> 40);
  }
}

// Parse a line from a state file.
static bool parse_dev_state_line(const char * line, persistent_dev_state & state)
{
  static regular_expression regex(
    "^ *"
     "((temperature-min)" // (1 (2)
     "|(temperature-max)" // (3)
     "|(self-test-errors)" // (4)
     "|(self-test-last-err-hour)" // (5)
     "|(scheduled-test-next-check)" // (6)
     "|(ata-error-count)"  // (7)
     "|(mail\\.([0-9]+)\\." // (8 (9)
       "((count)" // (10 (11)
       "|(first-sent-time)" // (12)
       "|(last-sent-time)" // (13)
       ")" // 10)
      ")" // 8)
     "|(ata-smart-attribute\\.([0-9]+)\\." // (14 (15)
       "((id)" // (16 (17)
       "|(val)" // (18)
       "|(worst)" // (19)
       "|(raw)" // (20)
       ")" // 16)
      ")" // 14)
     ")" // 1)
     " *= *([0-9]+)[ \n]*$", // (21)
    REG_EXTENDED
  );
  if (regex.empty())
    throw std::logic_error("parse_dev_state_line: invalid regex");

  const int nmatch = 1+21;
  regmatch_t match[nmatch];
  if (!regex.execute(line, nmatch, match))
    return false;
  if (match[nmatch-1].rm_so < 0)
    return false;

  uint64_t val = strtoull(line + match[nmatch-1].rm_so, (char **)0, 10);

  int m = 1;
  if (match[++m].rm_so >= 0)
    state.tempmin = (unsigned char)val;
  else if (match[++m].rm_so >= 0)
    state.tempmax = (unsigned char)val;
  else if (match[++m].rm_so >= 0)
    state.selflogcount = (unsigned char)val;
  else if (match[++m].rm_so >= 0)
    state.selfloghour = (unsigned short)val;
  else if (match[++m].rm_so >= 0)
    state.scheduled_test_next_check = (time_t)val;
  else if (match[++m].rm_so >= 0)
    state.ataerrorcount = (int)val;
  else if (match[m+=2].rm_so >= 0) {
    int i = atoi(line+match[m].rm_so);
    if (!(0 <= i && i < SMARTD_NMAIL))
      return false;
    if (i == MAILTYPE_TEST) // Don't suppress test mails
      return true;
    if (match[m+=2].rm_so >= 0)
      state.maillog[i].logged = (int)val;
    else if (match[++m].rm_so >= 0)
      state.maillog[i].firstsent = (time_t)val;
    else if (match[++m].rm_so >= 0)
      state.maillog[i].lastsent = (time_t)val;
    else
      return false;
  }
  else if (match[m+=5+1].rm_so >= 0) {
    int i = atoi(line+match[m].rm_so);
    if (!(0 <= i && i < NUMBER_ATA_SMART_ATTRIBUTES))
      return false;
    if (match[m+=2].rm_so >= 0)
      state.ata_attributes[i].id = (unsigned char)val;
    else if (match[++m].rm_so >= 0)
      state.ata_attributes[i].val = (unsigned char)val;
    else if (match[++m].rm_so >= 0)
      state.ata_attributes[i].worst = (unsigned char)val;
    else if (match[++m].rm_so >= 0)
      state.ata_attributes[i].raw = val;
    else
      return false;
  }
  else
    return false;
  return true;
}

// Read a state file.
static bool read_dev_state(const char * path, persistent_dev_state & state)
{
  stdio_file f(path, "r");
  if (!f) {
    if (errno != ENOENT)
      pout("Cannot read state file \"%s\"\n", path);
    return false;
  }
#ifdef __CYGWIN__
  setmode(fileno(f), O_TEXT); // Allow files with \r\n
#endif

  int good = 0, bad = 0;
  char line[256];
  while (fgets(line, sizeof(line), f)) {
    const char * s = line + strspn(line, " \t");
    if (!*s || *s == '#')
      continue;
    if (!parse_dev_state_line(line, state))
      bad++;
    else
      good++;
  }

  if (bad) {
    if (!good) {
      pout("%s: format error\n", path);
      return false;
    }
    pout("%s: %d invalid line(s) ignored\n", path, bad);
  }
  return true;
}

static void write_dev_state_line(FILE * f, const char * name, uint64_t val)
{
  if (val)
    fprintf(f, "%s = %"PRIu64"\n", name, val);
}

static void write_dev_state_line(FILE * f, const char * name1, int id, const char * name2, uint64_t val)
{
  if (val)
    fprintf(f, "%s.%d.%s = %"PRIu64"\n", name1, id, name2, val);
}

// Write a state file
static bool write_dev_state(const char * path, const persistent_dev_state & state)
{
  // Rename old "file" to "file~"
  std::string pathbak = path; pathbak += '~';
  unlink(pathbak.c_str());
  rename(path, pathbak.c_str());

  stdio_file f(path, "w");
  if (!f) {
    pout("Cannot create state file \"%s\"\n", path);
    return false;
  }

  fprintf(f, "# smartd state file\n");
  write_dev_state_line(f, "temperature-min", state.tempmin);
  write_dev_state_line(f, "temperature-max", state.tempmax);
  write_dev_state_line(f, "self-test-errors", state.selflogcount);
  write_dev_state_line(f, "self-test-last-err-hour", state.selfloghour);
  write_dev_state_line(f, "scheduled-test-next-check", state.scheduled_test_next_check);

  int i;
  for (i = 0; i < SMARTD_NMAIL; i++) {
    if (i == MAILTYPE_TEST) // Don't suppress test mails
      continue;
    const mailinfo & mi = state.maillog[i];
    if (!mi.logged)
      continue;
    write_dev_state_line(f, "mail", i, "count", mi.logged);
    write_dev_state_line(f, "mail", i, "first-sent-time", mi.firstsent);
    write_dev_state_line(f, "mail", i, "last-sent-time", mi.lastsent);
  }

  // ATA ONLY
  write_dev_state_line(f, "ata-error-count", state.ataerrorcount);

  for (i = 0; i < NUMBER_ATA_SMART_ATTRIBUTES; i++) {
    const persistent_dev_state::ata_attribute & pa = state.ata_attributes[i];
    if (!pa.id)
      continue;
    write_dev_state_line(f, "ata-smart-attribute", i, "id", pa.id);
    write_dev_state_line(f, "ata-smart-attribute", i, "val", pa.val);
    write_dev_state_line(f, "ata-smart-attribute", i, "worst", pa.worst);
    write_dev_state_line(f, "ata-smart-attribute", i, "raw", pa.raw);
  }

  return true;
}

// Write to the attrlog file
static bool write_dev_attrlog(const char * path, const persistent_dev_state & state)
{
  stdio_file f(path, "a");
  if (!f) {
    pout("Cannot create attribute log file \"%s\"\n", path);
    return false;
  }

  // ATA ONLY
  time_t now = time(0);
  struct tm * tms = gmtime(&now);
  fprintf(f, "%d-%02d-%02d %02d:%02d:%02d;",
             1900+tms->tm_year, 1+tms->tm_mon, tms->tm_mday,
             tms->tm_hour, tms->tm_min, tms->tm_sec);
  for (int i = 0; i < NUMBER_ATA_SMART_ATTRIBUTES; i++) {
    const persistent_dev_state::ata_attribute & pa = state.ata_attributes[i];
    if (!pa.id)
      continue;
    fprintf(f, "\t%d;%d;%"PRIu64";", pa.id, pa.val, pa.raw);
  }
  fprintf(f, "\n");

  return true;
}

// Write all state files. If write_always is false, don't write
// unless must_write is set.
static void write_all_dev_states(const dev_config_vector & configs,
                                 dev_state_vector & states,
                                 bool write_always = true)
{
  for (unsigned i = 0; i < states.size(); i++) {
    const dev_config & cfg = configs.at(i);
    if (cfg.state_file.empty())
      continue;
    dev_state & state = states[i];
    if (!write_always && !state.must_write)
      continue;
    if (!write_dev_state(cfg.state_file.c_str(), state))
      continue;
    state.must_write = false;
    if (write_always || debugmode)
      PrintOut(LOG_INFO, "Device: %s, state written to %s\n",
               cfg.name.c_str(), cfg.state_file.c_str());
  }
}

// Write to all attrlog files
static void write_all_dev_attrlogs(const dev_config_vector & configs,
                                   dev_state_vector & states)
{
  for (unsigned i = 0; i < states.size(); i++) {
    const dev_config & cfg = configs.at(i);
    if (cfg.attrlog_file.empty())
      continue;
    dev_state & state = states[i];
    write_dev_attrlog(cfg.attrlog_file.c_str(), state);
  }
}

// remove the PID file
void RemovePidFile(){
  if (!pid_file.empty()) {
    if (unlink(pid_file.c_str()))
      PrintOut(LOG_CRIT,"Can't unlink PID file %s (%s).\n", 
               pid_file.c_str(), strerror(errno));
    pid_file.clear();
  }
  return;
}

extern "C" { // signal handlers require C-linkage

//  Note if we catch a SIGUSR1
void USR1handler(int sig){
  if (SIGUSR1==sig)
    caughtsigUSR1=1;
  return;
}

#ifdef _WIN32
//  Note if we catch a SIGUSR2
void USR2handler(int sig){
  if (SIGUSR2==sig)
    caughtsigUSR2=1;
  return;
}
#endif

// Note if we catch a HUP (or INT in debug mode)
void HUPhandler(int sig){
  if (sig==SIGHUP)
    caughtsigHUP=1;
  else
    caughtsigHUP=2;
  return;
}

// signal handler for TERM, QUIT, and INT (if not in debug mode)
void sighandler(int sig){
  if (!caughtsigEXIT)
    caughtsigEXIT=sig;
  return;
}

} // extern "C"

// Cleanup, print Goodbye message and remove pidfile
static int Goodbye(int status)
{
  // delete PID file, if one was created
  RemovePidFile();

  // if we are exiting because of a code bug, tell user
  if (status==EXIT_BADCODE)
        PrintOut(LOG_CRIT, "Please inform " PACKAGE_BUGREPORT ", including output of smartd -V.\n");

  // and this should be the final output from smartd before it exits
  PrintOut(status?LOG_CRIT:LOG_INFO, "smartd is exiting (exit status %d)\n", status);

  return status;
}

#define ENVLENGTH 1024

// a replacement for setenv() which is not available on all platforms.
// Note that the string passed to putenv must not be freed or made
// invalid, since a pointer to it is kept by putenv(). This means that
// it must either be a static buffer or allocated off the heap. The
// string can be freed if the environment variable is redefined or
// deleted via another call to putenv(). So we keep these on the stack
// as long as the popen() call is underway.
int exportenv(char* stackspace, const char *name, const char *value){
  snprintf(stackspace,ENVLENGTH, "%s=%s", name, value);
  return putenv(stackspace);
}

char* dnsdomain(const char* hostname) {
  char *p = NULL;
#ifdef HAVE_GETADDRINFO
  static char canon_name[NI_MAXHOST];
  struct addrinfo *info = NULL;
  struct addrinfo hints;
  int err;

  memset(&hints, 0, sizeof(hints));
  hints.ai_flags = AI_CANONNAME;
  if ((err = getaddrinfo(hostname, NULL, &hints, &info)) || (!info)) {
    PrintOut(LOG_CRIT, "Error retrieving getaddrinfo(%s): %s\n", hostname, gai_strerror(err));
    return NULL;
  }
  if (info->ai_canonname) {
    strncpy(canon_name, info->ai_canonname, sizeof(canon_name));
    canon_name[NI_MAXHOST - 1] = '\0';
    p = canon_name;
    if ((p = strchr(canon_name, '.')))
      p++;
  }
  freeaddrinfo(info);
#elif HAVE_GETHOSTBYNAME
  struct hostent *hp;
  if ((hp = gethostbyname(hostname))) {
    // Does this work if gethostbyname() returns an IPv6 name in
    // colon/dot notation?  [BA]
    if ((p = strchr(hp->h_name, '.')))
      p++; // skip "."
  }
#else
  ARGUSED(hostname);
#endif
  return p;
}

#define EBUFLEN 1024

static void MailWarning(const dev_config & cfg, dev_state & state, int which, const char *fmt, ...)
                        __attribute__ ((format (printf, 4, 5)));

// If either address or executable path is non-null then send and log
// a warning email, or execute executable
static void MailWarning(const dev_config & cfg, dev_state & state, int which, const char *fmt, ...){
  char command[2048], message[256], hostname[256], domainname[256], additional[256],fullmessage[1024];
  char original[256], further[256], nisdomain[256], subject[256],dates[DATEANDEPOCHLEN];
  char environ_strings[11][ENVLENGTH];
  time_t epoch;
  va_list ap;
  const int day=24*3600;
  int days=0;
  const char * const whichfail[]={
    "EmailTest",                  // 0
    "Health",                     // 1
    "Usage",                      // 2
    "SelfTest",                   // 3
    "ErrorCount",                 // 4
    "FailedHealthCheck",          // 5
    "FailedReadSmartData",        // 6
    "FailedReadSmartErrorLog",    // 7
    "FailedReadSmartSelfTestLog", // 8
    "FailedOpenDevice",           // 9
    "CurrentPendingSector",       // 10
    "OfflineUncorrectableSector", // 11
    "Temperature"                 // 12
  };
  
  const char *unknown="[Unknown]";

  // See if user wants us to send mail
  if (cfg.emailaddress.empty() && cfg.emailcmdline.empty())
    return;

  std::string address = cfg.emailaddress;
  const char * executable = cfg.emailcmdline.c_str();

  // which type of mail are we sending?
  mailinfo * mail=(state.maillog)+which;

  // checks for sanity
  if (cfg.emailfreq<1 || cfg.emailfreq>3) {
    PrintOut(LOG_CRIT,"internal error in MailWarning(): cfg.mailwarn->emailfreq=%d\n",cfg.emailfreq);
    return;
  }
  if (which<0 || which>=SMARTD_NMAIL || sizeof(whichfail)!=SMARTD_NMAIL*sizeof(char *)) {
    PrintOut(LOG_CRIT,"Contact " PACKAGE_BUGREPORT "; internal error in MailWarning(): which=%d, size=%d\n",
             which, (int)sizeof(whichfail));
    return;
  }
  
  // Return if a single warning mail has been sent.
  if ((cfg.emailfreq==1) && mail->logged)
    return;

  // Return if this is an email test and one has already been sent.
  if (which == 0 && mail->logged)
    return;
  
  // To decide if to send mail, we need to know what time it is.
  epoch=time(NULL);

  // Return if less than one day has gone by
  if (cfg.emailfreq==2 && mail->logged && epoch<(mail->lastsent+day))
    return;

  // Return if less than 2^(logged-1) days have gone by
  if (cfg.emailfreq==3 && mail->logged) {
    days=0x01<<(mail->logged-1);
    days*=day;
    if  (epoch<(mail->lastsent+days))
      return;
  }

#ifdef HAVE_LIBCAP_NG
  if (enable_capabilities) {
    PrintOut(LOG_ERR, "Sending a mail was supressed. "
             "Mails can't be send when capabilites are enabled\n");
    return;
  }
#endif

  // record the time of this mail message, and the first mail message
  if (!mail->logged)
    mail->firstsent=epoch;
  mail->lastsent=epoch;
  
  // get system host & domain names (not null terminated if length=MAX) 
#ifdef HAVE_GETHOSTNAME
  if (gethostname(hostname, 256))
    strcpy(hostname, unknown);
  else {
    char *p=NULL;
    hostname[255]='\0';
    p = dnsdomain(hostname);
    if (p && *p) {
      strncpy(domainname, p, 255);
      domainname[255]='\0';
    } else
      strcpy(domainname, unknown);
  }
#else
  strcpy(hostname, unknown);
  strcpy(domainname, unknown);
#endif
  
#ifdef HAVE_GETDOMAINNAME
  if (getdomainname(nisdomain, 256))
    strcpy(nisdomain, unknown);
  else
    nisdomain[255]='\0';
#else
  strcpy(nisdomain, unknown);
#endif
  
  // print warning string into message
  va_start(ap, fmt);
  vsnprintf(message, 256, fmt, ap);
  va_end(ap);

  // appropriate message about further information
  additional[0]=original[0]=further[0]='\0';
  if (which) {
    sprintf(further,"You can also use the smartctl utility for further investigation.\n");

    switch (cfg.emailfreq) {
    case 1:
      sprintf(additional,"No additional email messages about this problem will be sent.\n");
      break;
    case 2:
      sprintf(additional,"Another email message will be sent in 24 hours if the problem persists.\n");
      break;
    case 3:
      sprintf(additional,"Another email message will be sent in %d days if the problem persists\n",
              (0x01)<<mail->logged);
      break;
    }
    if (cfg.emailfreq>1 && mail->logged) {
      dateandtimezoneepoch(dates, mail->firstsent);
      sprintf(original,"The original email about this issue was sent at %s\n", dates);
    }
  }
  
  snprintf(subject, 256,"SMART error (%s) detected on host: %s", whichfail[which], hostname);

  // If the user has set cfg.emailcmdline, use that as mailer, else "mail" or "mailx".
  if (!*executable)
#ifdef DEFAULT_MAILER
    executable = DEFAULT_MAILER ;
#else
#ifndef _WIN32
    executable = "mail";
#else
    executable = "blat"; // http://blat.sourceforge.net/
#endif
#endif

#ifndef _WIN32 // blat mailer needs comma
  // replace commas by spaces to separate recipients
  std::replace(address.begin(), address.end(), ',', ' ');
#endif
  // Export information in environment variables that will be useful
  // for user scripts
  exportenv(environ_strings[0], "SMARTD_MAILER", executable);
  exportenv(environ_strings[1], "SMARTD_MESSAGE", message);
  exportenv(environ_strings[2], "SMARTD_SUBJECT", subject);
  dateandtimezoneepoch(dates, mail->firstsent);
  exportenv(environ_strings[3], "SMARTD_TFIRST", dates);
  snprintf(dates, DATEANDEPOCHLEN,"%d", (int)mail->firstsent);
  exportenv(environ_strings[4], "SMARTD_TFIRSTEPOCH", dates);
  exportenv(environ_strings[5], "SMARTD_FAILTYPE", whichfail[which]);
  if (!address.empty())
    exportenv(environ_strings[6], "SMARTD_ADDRESS", address.c_str());
  exportenv(environ_strings[7], "SMARTD_DEVICESTRING", cfg.name.c_str());

  exportenv(environ_strings[8], "SMARTD_DEVICETYPE", cfg.dev_type.c_str());
  exportenv(environ_strings[9], "SMARTD_DEVICE", cfg.name.c_str());

  snprintf(fullmessage, 1024,
             "This email was generated by the smartd daemon running on:\n\n"
             "   host name: %s\n"
             "  DNS domain: %s\n"
             "  NIS domain: %s\n\n"
             "The following warning/error was logged by the smartd daemon:\n\n"
             "%s\n\n"
             "For details see host's SYSLOG (default: /var/log/messages).\n\n"
             "%s%s%s",
	     hostname, domainname, nisdomain, message, further, original, additional);
  exportenv(environ_strings[10], "SMARTD_FULLMESSAGE", fullmessage);

  // now construct a command to send this as EMAIL
#ifndef _WIN32
  if (!address.empty())
    snprintf(command, 2048, 
             "$SMARTD_MAILER -s '%s' %s 2>&1 << \"ENDMAIL\"\n"
	     "%sENDMAIL\n", subject, address.c_str(), fullmessage);
  else
    snprintf(command, 2048, "%s 2>&1", executable);
  
  // tell SYSLOG what we are about to do...
  const char * newadd = (!address.empty()? address.c_str() : "<nomailer>");
  const char * newwarn = (which? "Warning via" : "Test of");

  PrintOut(LOG_INFO,"%s %s to %s ...\n",