Merge branch 'upstream'

[mirror_smartmontools-debian.git] / atacmds.cpp

/*
 * atacmds.cpp
 * 
 * Home page of code is: http://smartmontools.sourceforge.net
 *
 * Copyright (C) 2002-6 Bruce Allen <smartmontools-support@lists.sourceforge.net>
 * Copyright (C) 1999-2000 Michael Cornwell <cornwell@acm.org>
 * Copyright (C) 2000 Andre Hedrick <andre@linux-ide.org>
 *
 * 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, write to the Free
 * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 * 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/
 * 
 */

#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <stdlib.h>
#include <ctype.h>

#include "config.h"
#include "int64.h"
#include "atacmds.h"
#include "scsiata.h"
#include "extern.h"
#include "utility.h"

const char *atacmds_c_cvsid="$Id: atacmds.cpp,v 1.176 2006/08/25 06:06:24 sxzzsf Exp $"
ATACMDS_H_CVSID CONFIG_H_CVSID EXTERN_H_CVSID INT64_H_CVSID SCSIATA_H_CVSID UTILITY_H_CVSID;

// to hold onto exit code for atexit routine
extern int exitstatus;

// for passing global control variables
extern smartmonctrl *con;

// These Drive Identity tables are taken from hdparm 5.2, and are also
// given in the ATA/ATAPI specs for the IDENTIFY DEVICE command.  Note
// that SMART was first added into the ATA/ATAPI-3 Standard with
// Revision 3 of the document, July 25, 1995.  Look at the "Document
// Status" revision commands at the beginning of
// http://www.t13.org/project/d2008r6.pdf to see this.
#define NOVAL_0                 0x0000
#define NOVAL_1                 0xffff
/* word 81: minor version number */
#define MINOR_MAX 0x22
const char *minor_str[] = {                     /* word 81 value: */
  "Device does not report version",             /* 0x0000       */
  "ATA-1 X3T9.2 781D prior to revision 4",      /* 0x0001       */
  "ATA-1 published, ANSI X3.221-1994",          /* 0x0002       */
  "ATA-1 X3T9.2 781D revision 4",               /* 0x0003       */
  "ATA-2 published, ANSI X3.279-1996",          /* 0x0004       */
  "ATA-2 X3T10 948D prior to revision 2k",      /* 0x0005       */
  "ATA-3 X3T10 2008D revision 1",               /* 0x0006       */ /* SMART NOT INCLUDED */
  "ATA-2 X3T10 948D revision 2k",               /* 0x0007       */
  "ATA-3 X3T10 2008D revision 0",               /* 0x0008       */ 
  "ATA-2 X3T10 948D revision 3",                /* 0x0009       */
  "ATA-3 published, ANSI X3.298-199x",          /* 0x000a       */
  "ATA-3 X3T10 2008D revision 6",               /* 0x000b       */ /* 1st VERSION WITH SMART */
  "ATA-3 X3T13 2008D revision 7 and 7a",        /* 0x000c       */
  "ATA/ATAPI-4 X3T13 1153D revision 6",         /* 0x000d       */
  "ATA/ATAPI-4 T13 1153D revision 13",          /* 0x000e       */
  "ATA/ATAPI-4 X3T13 1153D revision 7",         /* 0x000f       */
  "ATA/ATAPI-4 T13 1153D revision 18",          /* 0x0010       */
  "ATA/ATAPI-4 T13 1153D revision 15",          /* 0x0011       */
  "ATA/ATAPI-4 published, ANSI NCITS 317-1998", /* 0x0012       */
  "ATA/ATAPI-5 T13 1321D revision 3",           /* 0x0013       */
  "ATA/ATAPI-4 T13 1153D revision 14",          /* 0x0014       */
  "ATA/ATAPI-5 T13 1321D revision 1",           /* 0x0015       */
  "ATA/ATAPI-5 published, ANSI NCITS 340-2000", /* 0x0016       */
  "ATA/ATAPI-4 T13 1153D revision 17",          /* 0x0017       */
  "ATA/ATAPI-6 T13 1410D revision 0",           /* 0x0018       */
  "ATA/ATAPI-6 T13 1410D revision 3a",          /* 0x0019       */
  "ATA/ATAPI-7 T13 1532D revision 1",           /* 0x001a       */
  "ATA/ATAPI-6 T13 1410D revision 2",           /* 0x001b       */
  "ATA/ATAPI-6 T13 1410D revision 1",           /* 0x001c       */
  "ATA/ATAPI-7 published, ANSI INCITS 397-2005",/* 0x001d       */
  "ATA/ATAPI-7 T13 1532D revision 0",           /* 0x001e       */
  "reserved",                                   /* 0x001f       */
  "reserved",                                   /* 0x0020       */
  "ATA/ATAPI-7 T13 1532D revision 4a",          /* 0x0021       */
  "ATA/ATAPI-6 published, ANSI INCITS 361-2002" /* 0x0022       */
};

// NOTE ATA/ATAPI-4 REV 4 was the LAST revision where the device
// attribute structures were NOT completely vendor specific.  So any
// disk that is ATA/ATAPI-4 or above can not be trusted to show the
// vendor values in sensible format.

// Negative values below are because it doesn't support SMART
const int actual_ver[] = { 
  /* word 81 value: */
  0,            /* 0x0000       WARNING:        */
  1,            /* 0x0001       WARNING:        */
  1,            /* 0x0002       WARNING:        */
  1,            /* 0x0003       WARNING:        */
  2,            /* 0x0004       WARNING:   This array           */
  2,            /* 0x0005       WARNING:   corresponds          */
  -3, /*<== */  /* 0x0006       WARNING:   *exactly*            */
  2,            /* 0x0007       WARNING:   to the ATA/          */
  -3, /*<== */  /* 0x0008       WARNING:   ATAPI version        */
  2,            /* 0x0009       WARNING:   listed in            */
  3,            /* 0x000a       WARNING:   the                  */
  3,            /* 0x000b       WARNING:   minor_str            */
  3,            /* 0x000c       WARNING:   array                */
  4,            /* 0x000d       WARNING:   above.               */
  4,            /* 0x000e       WARNING:                        */
  4,            /* 0x000f       WARNING:   If you change        */
  4,            /* 0x0010       WARNING:   that one,            */
  4,            /* 0x0011       WARNING:   change this one      */
  4,            /* 0x0012       WARNING:   too!!!               */
  5,            /* 0x0013       WARNING:        */
  4,            /* 0x0014       WARNING:        */
  5,            /* 0x0015       WARNING:        */
  5,            /* 0x0016       WARNING:        */
  4,            /* 0x0017       WARNING:        */
  6,            /* 0x0018       WARNING:        */
  6,            /* 0x0019       WARNING:        */
  7,            /* 0x001a       WARNING:        */
  6,            /* 0x001b       WARNING:        */
  6,            /* 0x001c       WARNING:        */
  7,            /* 0x001d       WARNING:        */
  7,            /* 0x001e       WARNING:        */
  0,            /* 0x001f       WARNING:        */
  0,            /* 0x0020       WARNING:        */
  7,            /* 0x0021       WARNING:        */
  6             /* 0x0022       WARNING:        */
};

// When you add additional items to this list, you should then:
// 0 -- update this list
// 1 -- modify the following function parse_attribute_def()
// 2 -- if needed, modify ataPrintSmartAttribRawValue()
// 3 -  if needed, modify ataPrintSmartAttribName()
// 4 -- add #define PRESET_N_DESCRIPTION at top of knowndrives.c
// 5 -- add drive in question into knowndrives[] table in knowndrives.c
// 6 -- update smartctl.8
// 7 -- update smartd.8
// 8 -- do "make smartd.conf.5" to update smartd.conf.5
// 9 -- update CHANGELOG file
const char *vendorattributeargs[] = {
  // 0  defs[9]=1
  "9,minutes",
  // 1  defs[9]=3
  "9,seconds",
  // 2  defs[9]=2
  "9,temp",
  // 3  defs[220]=1
  "220,temp",
  // 4  defs[*]=253
  "N,raw8",
  // 5  defs[*]=254
  "N,raw16",
  // 6  defs[*]=255
  "N,raw48",
  // 7  defs[200]=1
  "200,writeerrorcount",
  // 8  defs[9]=4
  "9,halfminutes",
  // 9  defs[194]=1
  "194,10xCelsius",
  // 10 defs[194]=2
  "194,unknown",
  // 11 defs[193]=1
  "193,loadunload",
  // 12 defs[201]=1
  "201,detectedtacount",
  // 13 defs[192]=1
  "192,emergencyretractcyclect",
  // 14 defs[198]=1
  "198,offlinescanuncsectorct",
  // NULL should always terminate the array
  NULL
};

// This are the meanings of the Self-test failure checkpoint byte.
// This is in the self-test log at offset 4 bytes into the self-test
// descriptor and in the SMART READ DATA structure at byte offset
// 371. These codes are not well documented.  The meanings returned by
// this routine are used (at least) by Maxtor and IBM. Returns NULL if
// not recognized.  Currently the maximum length is 15 bytes.
const char *SelfTestFailureCodeName(unsigned char which){
  
  switch (which) {
  case 0:
    return "Write_Test";
  case 1:
    return "Servo_Basic";
  case 2:
    return "Servo_Random";
  case 3:
    return "G-list_Scan";
  case 4:
    return "Handling_Damage";
  case 5:
    return "Read_Scan";
  default:
    return NULL;
  }
}

// This is a utility function for parsing pairs like "9,minutes" or
// "220,temp", and putting the correct flag into the attributedefs
// array.  Returns 1 if problem, 0 if pair has been recongized.
int parse_attribute_def(char *pair, unsigned char **defsptr){
  int i,j;
  char temp[32];
  unsigned char *defs;

  // If array does not exist, allocate it
  if (!*defsptr && !(*defsptr=(unsigned char *)calloc(MAX_ATTRIBUTE_NUM, 1))){
    pout("Out of memory in parse_attribute_def\n");
    EXIT(1);
  }

  defs=*defsptr;

  // look along list and see if we find the pair
  for (i=0; vendorattributeargs[i] && strcmp(pair, vendorattributeargs[i]); i++);

  switch (i) {
  case 0:
    // attribute 9 is power on time in minutes
    defs[9]=1;
    return 0;
  case 1:
    // attribute 9 is power-on-time in seconds
    defs[9]=3;
    return 0;
  case 2:
    // attribute 9 is temperature in celsius
    defs[9]=2;
    return 0;
  case 3:
    // attribute 220 is temperature in celsius
    defs[220]=1;
    return 0;
  case 4:
    // print all attributes in raw 8-bit form
    for (j=0; j<MAX_ATTRIBUTE_NUM; j++)
      defs[j]=253;
    return 0;
  case 5:
    // print all attributes in raw 16-bit form
    for (j=0; j<MAX_ATTRIBUTE_NUM; j++)
      defs[j]=254;
    return 0;
  case 6:
    // print all attributes in raw 48-bit form
    for (j=0; j<MAX_ATTRIBUTE_NUM; j++)
      defs[j]=255;
    return 0;
  case 7:
    // attribute 200 is write error count
    defs[200]=1;
    return 0;
  case 8:
    // attribute 9 increments once every 30 seconds (power on time
    // measure)
    defs[9]=4;
    return 0;
  case 9:
    // attribute 194 is ten times disk temp in Celsius
    defs[194]=1;
    return 0;
  case 10:
    // attribute 194 is unknown
    defs[194]=2;
    return 0;
  case 11:
    // Hitachi : Attributes 193 has 2 values : 1 load, 1 normal unload
    defs[193]=1;
    return 0;
  case 12:
    // Fujitsu
    defs[201]=1;
    return 0;
  case 13:
    // Fujitsu
    defs[192]=1;
    return 0;
  case 14:
    // Fujitsu
    defs[198]=1;
    return 0;
  default:
    // pair not found
    break;
  }
  // At this point, either the pair was not found, or it is of the
  // form N,uninterpreted, in which case we need to parse N
  j=sscanf(pair,"%d,%14s", &i, temp);
 
  // if no match to pattern, unrecognized
  if (j!=2 || i<0 || i >255)
    return 1;

  // check for recognized strings
  if (!strcmp(temp, "raw8")) {
    defs[i]=253;
    return 0;
  }
  
  // check for recognized strings
  if (!strcmp(temp, "raw16")) {
    defs[i]=254;
    return 0;
  }
  
  // check for recognized strings
  if (!strcmp(temp, "raw48")) {
    defs[i]=255;
    return 0;
  }
 
  // didn't recognize the string
  return 1;
}

// Structure used in sorting the array vendorattributeargs[].
typedef struct vaa_pair_s {
  const char *vaa;
  const char *padded_vaa;
} vaa_pair;

// Returns a copy of s with all numbers of less than three digits padded with
// leading zeros.  Returns NULL if there isn't enough memory available.  The
// memory for the string is dynamically allocated and should be freed by the
// caller.
char *pad_numbers(const char *s)
{
  char c, *t, *u;
  const char *r;
  int i, len, ndigits = 0;

  // Allocate the maximum possible amount of memory needed.
  if (!(t = (char *)malloc(strlen(s)*2+2)))
    return NULL;

  // Copy the string s to t, padding any numbers of less than three digits
  // with leading zeros.  The string is copied backwards to simplify the code.
  r = s + strlen(s);
  u = t;
  while (( r-- >= s)) {
    if (isdigit((int)*r))
      ndigits++;
    else if (ndigits > 0) {
      while (ndigits++ < 3)
        *u++ = '0';
      ndigits = 0;
    }
    *u++ = *r;
  }
  *u = '\0';

  // Reverse the string in t.
  len = strlen(t);
  for (i = 0; i < len/2; i++) {
    c          = t[i];
    t[i]       = t[len-1-i];
    t[len-1-i] = c;
  }

  return t;
}

// Comparison function for qsort().  Used by sort_vendorattributeargs().
int compare_vaa_pairs(const void *a, const void *b)
{
  vaa_pair *p = (vaa_pair *)a;
  vaa_pair *q = (vaa_pair *)b;

  return strcmp(p->padded_vaa, q->padded_vaa);
}

// Returns a sorted list of vendorattributeargs or NULL if there is not enough
// memory available.  The memory for the list is allocated dynamically and
// should be freed by the caller.
// To perform the sort, any numbers in the strings are padded out to three
// digits by adding leading zeros.  For example,
//
//    "9,minutes"  becomes  "009,minutes"
//    "N,raw16"    becomes  "N,raw016"
//
// and the original strings are paired with the padded strings.  The list of
// pairs is then sorted by comparing the padded strings (using strcmp) and the
// result is then the list of unpadded strings.
//
const char **sort_vendorattributeargs(void) {
  const char **ps, **sorted_list = NULL;
  vaa_pair *pairs, *pp;
  int count, i;

  // Figure out how many strings are in vendorattributeargs[] (not including
  // the terminating NULL).
  count = (sizeof vendorattributeargs) / sizeof(char *) - 1;

  // Construct a list of pairs of strings from vendorattributeargs[] and their
  // padded equivalents.
  if (!(pairs = (vaa_pair *)malloc(sizeof(vaa_pair) * count)))
    goto END;
  for (ps = vendorattributeargs, pp = pairs; *ps; ps++, pp++) {
    pp->vaa = *ps;
    if (!(pp->padded_vaa = pad_numbers(*ps)))
      goto END;
  }

  // Sort the array of vaa_pair structures by comparing the padded strings
  // using strcmp().
  qsort(pairs, count, sizeof(vaa_pair), compare_vaa_pairs);

  // Construct the sorted list of strings.
  if (!(sorted_list = (const char **)malloc(sizeof vendorattributeargs)))
    goto END;
  for (ps = sorted_list, pp = pairs, i = 0; i < count; ps++, pp++, i++)
    *ps = pp->vaa;
  *ps = NULL;

END:
  if (pairs) {
    for (i = 0; i < count; i++)
      if (pairs[i].padded_vaa)
        free((void *)pairs[i].padded_vaa);
    free((void *)pairs);
  }

  // If there was a problem creating the list then sorted_list should now
  // contain NULL.
  return sorted_list;
}

// Function to return a multiline string containing a list of the arguments in 
// vendorattributeargs[].  The strings are preceeded by tabs and followed
// (except for the last) by newlines.
// This function allocates the required memory for the string and the caller
// must use free() to free it.  It returns NULL if the required memory can't
// be allocated.
char *create_vendor_attribute_arg_list(void){
  const char **ps, **sorted;
  char *s;
  int len;

  // Get a sorted list of vendor attribute arguments.  If the sort fails
  // (which should only happen if the system is really low on memory) then just
  // use the unordered list.
  if (!(sorted = (const char **) sort_vendorattributeargs()))
    sorted = vendorattributeargs;

  // Calculate the required number of characters
  len = 1;                // At least one char ('\0')
  for (ps = sorted; *ps != NULL; ps++) {
    len += 1;             // For the tab
    len += strlen(*ps);   // For the actual argument string
    if (*(ps+1))
      len++;              // For the newline if required
  }

  // Attempt to allocate memory for the string
  if (!(s = (char *)malloc(len)))
    return NULL;

  // Construct the string
  *s = '\0';
  for (ps = sorted; *ps != NULL; ps++) {
    strcat(s, "\t");
    strcat(s, *ps);
    if (*(ps+1))
      strcat(s, "\n");
  }

  free((char **)sorted);

  // Return a pointer to the string
  return s;
}

// swap two bytes.  Point to low address
void swap2(char *location){
  char tmp=*location;
  *location=*(location+1);
  *(location+1)=tmp;
  return;
}

// swap four bytes.  Point to low address
void swap4(char *location){
  char tmp=*location;
  *location=*(location+3);
  *(location+3)=tmp;
  swap2(location+1);
  return;
}

// swap eight bytes.  Points to low address
void swap8(char *location){
  char tmp=*location;
  *location=*(location+7);
  *(location+7)=tmp;
  tmp=*(location+1);
  *(location+1)=*(location+6);
  *(location+6)=tmp;
  swap4(location+2);
  return;
}

static char *commandstrings[]={
  "SMART ENABLE",
  "SMART DISABLE",
  "SMART AUTOMATIC ATTRIBUTE SAVE",
  "SMART IMMEDIATE OFFLINE",
  "SMART AUTO OFFLINE",
  "SMART STATUS",
  "SMART STATUS CHECK",
  "SMART READ ATTRIBUTE VALUES",
  "SMART READ ATTRIBUTE THRESHOLDS",
  "SMART READ LOG",
  "IDENTIFY DEVICE",
  "IDENTIFY PACKET DEVICE",
  "CHECK POWER MODE",
  "SMART WRITE LOG",
  "WARNING (UNDEFINED COMMAND -- CONTACT DEVELOPERS AT " PACKAGE_BUGREPORT ")\n"
};

void prettyprint(unsigned char *stuff, char *name){
  int i,j;
  pout("\n===== [%s] DATA START (BASE-16) =====\n", name);
  for (i=0; i<32; i++){
    pout("%03d-%03d: ", 16*i, 16*(i+1)-1);
    for (j=0; j<15; j++)
      pout("%02x ",*stuff++);
    pout("%02x\n",*stuff++);
  }
  pout("===== [%s] DATA END (512 Bytes) =====\n\n", name);
}

// This function provides the pretty-print reporting for SMART
// commands: it implements the various -r "reporting" options for ATA
// ioctls.
int smartcommandhandler(int device, smart_command_set command, int select, char *data){
  int retval;

  // This conditional is true for commands that return data
  int getsdata=(command==PIDENTIFY || 
                command==IDENTIFY || 
                command==READ_LOG || 
                command==READ_THRESHOLDS || 
                command==READ_VALUES ||
                command==CHECK_POWER_MODE);

  int sendsdata=(command==WRITE_LOG);
  
  // If reporting is enabled, say what the command will be before it's executed
  if (con->reportataioctl){
          // conditional is true for commands that use parameters
          int usesparam=(command==READ_LOG || 
                         command==AUTO_OFFLINE || 
                         command==AUTOSAVE || 
                         command==IMMEDIATE_OFFLINE ||
                         command==WRITE_LOG);
                  
    pout("\nREPORT-IOCTL: DeviceFD=%d Command=%s", device, commandstrings[command]);
    if (usesparam)
      pout(" InputParameter=%d\n", select);
    else
      pout("\n");
  }
  
  if ((getsdata || sendsdata) && !data){
    pout("REPORT-IOCTL: Unable to execute command %s : data destination address is NULL\n", commandstrings[command]);
    return -1;
  }
  
  // The reporting is cleaner, and we will find coding bugs faster, if
  // the commands that failed clearly return empty (zeroed) data
  // structures
  if (getsdata) {
    if (command==CHECK_POWER_MODE)
      data[0]=0;
    else
      memset(data, '\0', 512);
  }


  // If reporting is enabled, say what input was sent to the command
  if (con->reportataioctl && sendsdata){
    pout("REPORT-IOCTL: DeviceFD=%d Command=%s", device, commandstrings[command]);
    // if requested, pretty-print the output data structure
    if (con->reportataioctl>1)
      prettyprint((unsigned char *)data, commandstrings[command]);
  }

  // In case the command produces an error, we'll want to know what it is:
  errno=0;
  
  // now execute the command
  switch (con->controller_type) {
  case CONTROLLER_3WARE_678K:
  case CONTROLLER_3WARE_678K_CHAR:
  case CONTROLLER_3WARE_9000_CHAR:
    retval=escalade_command_interface(device, con->controller_port-1, con->controller_type, command, select, data);
    if (retval &&  con->controller_port<=0)
      pout("WARNING: apparently missing '-d 3ware,N' disk specification\n");
    break;
  case CONTROLLER_MARVELL_SATA:
    retval=marvell_command_interface(device, command, select, data);
    break;
  case CONTROLLER_SAT:
    retval=sat_command_interface(device, command, select, data);
    break;
  case CONTROLLER_HPT:
    retval=highpoint_command_interface(device, command, select, data);
    break;
  default:
    retval=ata_command_interface(device, command, select, data);
  }

  // If reporting is enabled, say what output was produced by the command
  if (con->reportataioctl){
    if (errno)
      pout("REPORT-IOCTL: DeviceFD=%d Command=%s returned %d errno=%d [%s]\n", 
           device, commandstrings[command], retval, errno, strerror(errno));
    else
      pout("REPORT-IOCTL: DeviceFD=%d Command=%s returned %d\n",
           device, commandstrings[command], retval);
    
    // if requested, pretty-print the output data structure
    if (con->reportataioctl>1 && getsdata) {
      if (command==CHECK_POWER_MODE)
        pout("Sector Count Register (BASE-16): %02x\n", (unsigned char)(*data));
      else
        prettyprint((unsigned char *)data, commandstrings[command]);
    }
  }
  return retval;
}


// This function computes the checksum of a single disk sector (512
// bytes).  Returns zero if checksum is OK, nonzero if the checksum is
// incorrect.  The size (512) is correct for all SMART structures.
unsigned char checksum(unsigned char *buffer){
  unsigned char sum=0;
  int i;
  
  for (i=0; i<512; i++)
    sum+=buffer[i];

  return sum;
}

// returns -1 if command fails or the device is in Sleep mode, else
// value of Sector Count register.  Sector Count result values:
//   00h device is in Standby mode. 
//   80h device is in Idle mode.
//   FFh device is in Active mode or Idle mode.

int ataCheckPowerMode(int device) {
  unsigned char result;

  if ((smartcommandhandler(device, CHECK_POWER_MODE, 0, (char *)&result)))
    return -1;

  if (result!=0 && result!=0x80 && result!=0xff)
    pout("ataCheckPowerMode(): ATA CHECK POWER MODE returned unknown Sector Count Register value %02x\n", result);

  return (int)result;
}




// Reads current Device Identity info (512 bytes) into buf.  Returns 0
// if all OK.  Returns -1 if no ATA Device identity can be
// established.  Returns >0 if Device is ATA Packet Device (not SMART
// capable).  The value of the integer helps identify the type of
// Packet device, which is useful so that the user can connect the
// formal device number with whatever object is inside their computer.
int ataReadHDIdentity (int device, struct ata_identify_device *buf){
  unsigned short *rawshort=(unsigned short *)buf;
  unsigned char  *rawbyte =(unsigned char  *)buf;

  // See if device responds either to IDENTIFY DEVICE or IDENTIFY
  // PACKET DEVICE
  if ((smartcommandhandler(device, IDENTIFY, 0, (char *)buf))){
    if (smartcommandhandler(device, PIDENTIFY, 0, (char *)buf)){
      return -1; 
    }
  }

#ifndef __NetBSD__
  // if machine is big-endian, swap byte order as needed
  // (the NetBSD kernel does deliver the results in host byte order)
  if (isbigendian()){
    int i;
    
    // swap various capability words that are needed
    for (i=0; i<33; i++)
      swap2((char *)(buf->words047_079+i));
    
    for (i=80; i<=87; i++)
      swap2((char *)(rawshort+i));
    
    for (i=0; i<168; i++)
      swap2((char *)(buf->words088_255+i));
  }
#endif
  
  // If there is a checksum there, validate it
  if ((rawshort[255] & 0x00ff) == 0x00a5 && checksum(rawbyte))
    checksumwarning("Drive Identity Structure");
  
  // If this is a PACKET DEVICE, return device type
  if (rawbyte[1] & 0x80)
    return 1+(rawbyte[1] & 0x1f);
  
  // Not a PACKET DEVICE
  return 0;
}

// Returns ATA version as an integer, and a pointer to a string
// describing which revision.  Note that Revision 0 of ATA-3 does NOT
// support SMART.  For this one case we return -3 rather than +3 as
// the version number.  See notes above.
int ataVersionInfo (const char** description, struct ata_identify_device *drive, unsigned short *minor){
  unsigned short major;
  int i;

  // check that arrays at the top of this file are defined
  // consistently
  if (sizeof(minor_str) != sizeof(char *)*(1+MINOR_MAX)){
    pout("Internal error in ataVersionInfo().  minor_str[] size %d\n"
         "is not consistent with value of MINOR_MAX+1 = %d\n", 
         (int)(sizeof(minor_str)/sizeof(char *)), MINOR_MAX+1);
    fflush(NULL);
    abort();
  }
  if (sizeof(actual_ver) != sizeof(int)*(1+MINOR_MAX)){
    pout("Internal error in ataVersionInfo().  actual_ver[] size %d\n"
         "is not consistent with value of MINOR_MAX = %d\n",
         (int)(sizeof(actual_ver)/sizeof(int)), MINOR_MAX+1);
    fflush(NULL);
    abort();
  }

  // get major and minor ATA revision numbers
  major=drive->major_rev_num;
  *minor=drive->minor_rev_num;
  
  // First check if device has ANY ATA version information in it
  if (major==NOVAL_0 || major==NOVAL_1) {
    *description=NULL;
    return -1;
  }
  
  // The minor revision number has more information - try there first
  if (*minor && (*minor<=MINOR_MAX)){
    int std = actual_ver[*minor];
    if (std) {
      *description=minor_str[*minor];
      return std;
    }
  }
  
  // HDPARM has a very complicated algorithm from here on. Since SMART only
  // exists on ATA-3 and later standards, let's punt on this.  If you don't
  // like it, please fix it.  The code's in CVS.
  for (i=15; i>0; i--)
    if (major & (0x1<<i))
      break;
  
  *description=NULL; 
  if (i==0)
    return 1;
  else
    return i;
}

// returns 1 if SMART supported, 0 if SMART unsupported, -1 if can't tell
int ataSmartSupport(struct ata_identify_device *drive){
  unsigned short word82=drive->command_set_1;
  unsigned short word83=drive->command_set_2;
  
  // check if words 82/83 contain valid info
  if ((word83>>14) == 0x01)
    // return value of SMART support bit 
    return word82 & 0x0001;
  
  // since we can're rely on word 82, we don't know if SMART supported
  return -1;
}

// returns 1 if SMART enabled, 0 if SMART disabled, -1 if can't tell
int ataIsSmartEnabled(struct ata_identify_device *drive){
  unsigned short word85=drive->cfs_enable_1;
  unsigned short word87=drive->csf_default;
  
  // check if words 85/86/87 contain valid info
  if ((word87>>14) == 0x01)
    // return value of SMART enabled bit
    return word85 & 0x0001;
  
  // Since we can't rely word85, we don't know if SMART is enabled.
  return -1;
}


// Reads SMART attributes into *data
int ataReadSmartValues(int device, struct ata_smart_values *data){      
  
  if (smartcommandhandler(device, READ_VALUES, 0, (char *)data)){
    syserror("Error SMART Values Read failed");
    return -1;
  }

  // compute checksum
  if (checksum((unsigned char *)data))
    checksumwarning("SMART Attribute Data Structure");
  
  // byte swap if needed
  if (isbigendian()){
    int i;
    swap2((char *)&(data->revnumber));
    swap2((char *)&(data->total_time_to_complete_off_line));
    swap2((char *)&(data->smart_capability));
    for (i=0; i<NUMBER_ATA_SMART_ATTRIBUTES; i++){
      struct ata_smart_attribute *x=data->vendor_attributes+i;
      swap2((char *)&(x->flags));
    }
  }

  return 0;
}


// This corrects some quantities that are byte reversed in the SMART
// SELF TEST LOG
void fixsamsungselftestlog(struct ata_smart_selftestlog *data){
  int i;
  
  // bytes 508/509 (numbered from 0) swapped (swap of self-test index
  // with one byte of reserved.
  swap2((char *)&(data->mostrecenttest));

  // LBA low register (here called 'selftestnumber", containing
  // information about the TYPE of the self-test) is byte swapped with
  // Self-test execution status byte.  These are bytes N, N+1 in the
  // entries.
  for (i=0; i<21; i++)
    swap2((char *)&(data->selftest_struct[i].selftestnumber));

  return;
}

// Reads the Self Test Log (log #6)
int ataReadSelfTestLog (int device, struct ata_smart_selftestlog *data){

  // get data from device
  if (smartcommandhandler(device, READ_LOG, 0x06, (char *)data)){
    syserror("Error SMART Error Self-Test Log Read failed");
    return -1;
  }

  // compute its checksum, and issue a warning if needed
  if (checksum((unsigned char *)data))
    checksumwarning("SMART Self-Test Log Structure");
  
  // fix firmware bugs in self-test log
  if (con->fixfirmwarebug == FIX_SAMSUNG)
    fixsamsungselftestlog(data);

  // fix endian order, if needed
  if (isbigendian()){
    int i;
    swap2((char*)&(data->revnumber));
    for (i=0; i<21; i++){
      struct ata_smart_selftestlog_struct *x=data->selftest_struct+i;
      swap2((char *)&(x->timestamp));
      swap4((char *)&(x->lbafirstfailure));
    }
  }

  return 0;
}


// Reads the Log Directory (log #0).  Note: NO CHECKSUM!!
int ataReadLogDirectory (int device, struct ata_smart_log_directory *data){     
  
  // get data from device
  if (smartcommandhandler(device, READ_LOG, 0x00, (char *)data)){
    return -1;
  }

  // swap endian order if needed
  if (isbigendian()){
    swap2((char *)&(data->logversion));
  }
  
  return 0;
}


// Reads the selective self-test log (log #9)
int ataReadSelectiveSelfTestLog(int device, struct ata_selective_self_test_log *data){  
  
  // get data from device
  if (smartcommandhandler(device, READ_LOG, 0x09, (char *)data)){
    syserror("Error SMART Read Selective Self-Test Log failed");
    return -1;
  }
   
  // compute its checksum, and issue a warning if needed
  if (checksum((unsigned char *)data))
    checksumwarning("SMART Selective Self-Test Log Structure");
  
  // swap endian order if needed
  if (isbigendian()){
    int i;
    swap2((char *)&(data->logversion));
    for (i=0;i<5;i++){
      swap8((char *)&(data->span[i].start));
      swap8((char *)&(data->span[i].end));
    }
    swap8((char *)&(data->currentlba));
    swap2((char *)&(data->currentspan));
    swap2((char *)&(data->flags));
    swap2((char *)&(data->pendingtime));
  }
  
  if (data->logversion != 1)
    pout("SMART Selective Self-Test Log Data Structure Revision Number (%d) should be 1\n", data->logversion);
  
  return 0;
}

// Writes the selective self-test log (log #9)
int ataWriteSelectiveSelfTestLog(int device, struct ata_smart_values *sv){   
  int i;
  struct ata_selective_self_test_log sstlog, *data=&sstlog;
  unsigned char cksum=0;
  unsigned char *ptr=(unsigned char *)data;
  
  // Read log
  if (ataReadSelectiveSelfTestLog(device, data)) {
    pout("Since Read failed, will not attempt to WRITE Selective Self-test Log\n");
    return -1;
  }
  
  // Fix logversion if needed
  if (data->logversion !=1) {
    pout("Error SMART Selective Self-Test Log Data Structure Revision not recognized\n"
         "Revision number should be 1 but is %d.  To be safe, aborting WRITE LOG\n", data->logversion);
    return -2;
  }

  // Host is NOT allowed to write selective self-test log if a selective
  // self-test is in progress.
  if (0<data->currentspan && data->currentspan<6 && ((sv->self_test_exec_status)>>4)==15) {
    pout("Error SMART Selective or other Self-Test in progress.\n");
    return -4;
  }
  
  // Clear spans
  for (i=0; i<5; i++)
    memset(data->span+i, 0, sizeof(struct test_span));
  
  // Set spans for testing 
  for (i=0; i<con->smartselectivenumspans; i++){
    data->span[i].start = con->smartselectivespan[i][0];
    data->span[i].end   = con->smartselectivespan[i][1];
  }

  // host must initialize to zero before initiating selective self-test
  data->currentlba=0;
  data->currentspan=0;
  
  // Perform off-line scan after selective test?
  if (1 == con->scanafterselect)
    // NO
    data->flags &= ~SELECTIVE_FLAG_DOSCAN;
  else if (2 == con->scanafterselect)
    // YES
    data->flags |= SELECTIVE_FLAG_DOSCAN;
  
  // Must clear active and pending flags before writing
  data->flags &= ~(SELECTIVE_FLAG_ACTIVE);  
  data->flags &= ~(SELECTIVE_FLAG_PENDING);

  // modify pending time?
  if (con->pendingtime)
    data->pendingtime=(unsigned short)(con->pendingtime-1);

  // Set checksum to zero, then compute checksum
  data->checksum=0;
  for (i=0; i<512; i++)
    cksum+=ptr[i];
  cksum=~cksum;
  cksum+=1;
  data->checksum=cksum;

    // swap endian order if needed
  if (isbigendian()){
    int i;
    swap2((char *)&(data->logversion));
    for (i=0;i<5;i++){
      swap8((char *)&(data->span[i].start));
      swap8((char *)&(data->span[i].end));
    }
    swap8((char *)&(data->currentlba));
    swap2((char *)&(data->currentspan));
    swap2((char *)&(data->flags));
    swap2((char *)&(data->pendingtime));
  }

  // write new selective self-test log
  if (smartcommandhandler(device, WRITE_LOG, 0x09, (char *)data)){
    syserror("Error Write Selective Self-Test Log failed");
    return -3;
  }

  return 0;
}

// This corrects some quantities that are byte reversed in the SMART
// ATA ERROR LOG.
void fixsamsungerrorlog(struct ata_smart_errorlog *data){
  int i,j;
  
  // FIXED IN SAMSUNG -25 FIRMWARE???
  // Device error count in bytes 452-3
  swap2((char *)&(data->ata_error_count));
  
  // FIXED IN SAMSUNG -22a FIRMWARE
  // step through 5 error log data structures
  for (i=0; i<5; i++){
    // step through 5 command data structures
    for (j=0; j<5; j++)
      // Command data structure 4-byte millisec timestamp.  These are
      // bytes (N+8, N+9, N+10, N+11).
      swap4((char *)&(data->errorlog_struct[i].commands[j].timestamp));
    // Error data structure two-byte hour life timestamp.  These are
    // bytes (N+28, N+29).
    swap2((char *)&(data->errorlog_struct[i].error_struct.timestamp));
  }
  return;
}

// NEEDED ONLY FOR SAMSUNG -22 (some) -23 AND -24?? FIRMWARE
void fixsamsungerrorlog2(struct ata_smart_errorlog *data){
  // Device error count in bytes 452-3
  swap2((char *)&(data->ata_error_count));
  return;
}

// Reads the Summary SMART Error Log (log #1). The Comprehensive SMART
// Error Log is #2, and the Extended Comprehensive SMART Error log is
// #3
int ataReadErrorLog (int device, struct ata_smart_errorlog *data){      
  
  // get data from device
  if (smartcommandhandler(device, READ_LOG, 0x01, (char *)data)){
    syserror("Error SMART Error Log Read failed");
    return -1;
  }
  
  // compute its checksum, and issue a warning if needed
  if (checksum((unsigned char *)data))
    checksumwarning("SMART ATA Error Log Structure");
  
  // Some disks have the byte order reversed in some SMART Summary
  // Error log entries
  if (con->fixfirmwarebug == FIX_SAMSUNG)
    fixsamsungerrorlog(data);
  else if (con->fixfirmwarebug == FIX_SAMSUNG2)
    fixsamsungerrorlog2(data);

  // Correct endian order if necessary
  if (isbigendian()){
    int i,j;
    
    // Device error count in bytes 452-3
    swap2((char *)&(data->ata_error_count));
    
    // step through 5 error log data structures
    for (i=0; i<5; i++){
      // step through 5 command data structures
      for (j=0; j<5; j++)
        // Command data structure 4-byte millisec timestamp
        swap4((char *)&(data->errorlog_struct[i].commands[j].timestamp));
      // Error data structure life timestamp
      swap2((char *)&(data->errorlog_struct[i].error_struct.timestamp));
    }
  }
  
  return 0;
}

int ataReadSmartThresholds (int device, struct ata_smart_thresholds_pvt *data){
  
  // get data from device
  if (smartcommandhandler(device, READ_THRESHOLDS, 0, (char *)data)){
    syserror("Error SMART Thresholds Read failed");
    return -1;
  }
  
  // compute its checksum, and issue a warning if needed
  if (checksum((unsigned char *)data))
    checksumwarning("SMART Attribute Thresholds Structure");
  
  // byte swap if needed
  if (isbigendian())
    swap2((char *)&(data->revnumber));

  return 0;
}

int ataEnableSmart (int device ){       
  if (smartcommandhandler(device, ENABLE, 0, NULL)){
    syserror("Error SMART Enable failed");
    return -1;
  }
  return 0;
}

int ataDisableSmart (int device ){      
  
  if (smartcommandhandler(device, DISABLE, 0, NULL)){
    syserror("Error SMART Disable failed");
    return -1;
  }  
  return 0;
}

int ataEnableAutoSave(int device){  
  if (smartcommandhandler(device, AUTOSAVE, 241, NULL)){
    syserror("Error SMART Enable Auto-save failed");
    return -1;
  }
  return 0;
}

int ataDisableAutoSave(int device){
  
  if (smartcommandhandler(device, AUTOSAVE, 0, NULL)){
    syserror("Error SMART Disable Auto-save failed");
    return -1;
  }
  return 0;
}

// In *ALL* ATA standards the Enable/Disable AutoOffline command is
// marked "OBSOLETE". It is defined in SFF-8035i Revision 2, and most
// vendors still support it for backwards compatibility. IBM documents
// it for some drives.
int ataEnableAutoOffline (int device ){ 
  
  /* timer hard coded to 4 hours */  
  if (smartcommandhandler(device, AUTO_OFFLINE, 248, NULL)){
    syserror("Error SMART Enable Automatic Offline failed");
    return -1;
  }
  return 0;
}

// Another Obsolete Command.  See comments directly above, associated
// with the corresponding Enable command.
int ataDisableAutoOffline (int device ){        
  
  if (smartcommandhandler(device, AUTO_OFFLINE, 0, NULL)){
    syserror("Error SMART Disable Automatic Offline failed");
    return -1;
  }
  return 0;
}

// If SMART is enabled, supported, and working, then this call is
// guaranteed to return 1, else zero.  Note that it should return 1
// regardless of whether the disk's SMART status is 'healthy' or
// 'failing'.
int ataDoesSmartWork(int device){
  int retval=smartcommandhandler(device, STATUS, 0, NULL);

  if (-1 == retval)
    return 0;

  return 1;
}

// This function uses a different interface (DRIVE_TASK) than the
// other commands in this file.
int ataSmartStatus2(int device){
  return smartcommandhandler(device, STATUS_CHECK, 0, NULL);  
}

// This is the way to execute ALL tests: offline, short self-test,
// extended self test, with and without captive mode, etc.
int ataSmartTest(int device, int testtype, struct ata_smart_values *sv) {     
  char cmdmsg[128],*type,*captive;
  int errornum, cap, retval, select=0;

  // Boolean, if set, says test is captive
  cap=testtype & CAPTIVE_MASK;

  // Set up strings that describe the type of test
  if (cap)
    captive="captive";
  else
    captive="off-line";
  
  if (testtype==OFFLINE_FULL_SCAN)
    type="off-line";
  else  if (testtype==SHORT_SELF_TEST || testtype==SHORT_CAPTIVE_SELF_TEST)
    type="Short self-test";
  else if (testtype==EXTEND_SELF_TEST || testtype==EXTEND_CAPTIVE_SELF_TEST)
    type="Extended self-test";
  else if (testtype==CONVEYANCE_SELF_TEST || testtype==CONVEYANCE_CAPTIVE_SELF_TEST)
    type="Conveyance self-test";
  else if ((select=(testtype==SELECTIVE_SELF_TEST || testtype==SELECTIVE_CAPTIVE_SELF_TEST)))
    type="Selective self-test";
  else
    type="[Unrecognized] self-test";
  
  // If doing a selective self-test, first use WRITE_LOG to write the
  // selective self-test log.
  if (select && (retval=ataWriteSelectiveSelfTestLog(device, sv))) {
    if (retval==-4)
      pout("Can't start selective self-test without aborting current test: use '-X' option to smartctl.\n");
    return retval;
  }

  //  Print ouf message that we are sending the command to test
  if (testtype==ABORT_SELF_TEST)
    sprintf(cmdmsg,"Abort SMART off-line mode self-test routine");
  else
    sprintf(cmdmsg,"Execute SMART %s routine immediately in %s mode",type,captive);
  pout("Sending command: \"%s\".\n",cmdmsg);

  if (select) {
    int i;
    pout("SPAN         STARTING_LBA           ENDING_LBA\n");
    for (i = 0; i < con->smartselectivenumspans; i++)
      pout("   %d %20"PRId64" %20"PRId64"\n", i,
           con->smartselectivespan[i][0],
           con->smartselectivespan[i][1]);
  }
  
  // Now send the command to test
  errornum=smartcommandhandler(device, IMMEDIATE_OFFLINE, testtype, NULL);
  
  if (errornum && !(cap && errno==EIO)){
    char errormsg[128];
    sprintf(errormsg,"Command \"%s\" failed",cmdmsg); 
    syserror(errormsg);
    pout("\n");
    return -1;
  }
  
  // Since the command succeeded, tell user
  if (testtype==ABORT_SELF_TEST)
    pout("Self-testing aborted!\n");
  else
    pout("Drive command \"%s\" successful.\nTesting has begun.\n",cmdmsg);
  return 0;
}

/* Test Time Functions */
int TestTime(struct ata_smart_values *data,int testtype){
  switch (testtype){
  case OFFLINE_FULL_SCAN:
    return (int) data->total_time_to_complete_off_line;
  case SHORT_SELF_TEST:
  case SHORT_CAPTIVE_SELF_TEST:
    return (int) data->short_test_completion_time;
  case EXTEND_SELF_TEST:
  case EXTEND_CAPTIVE_SELF_TEST:
    return (int) data->extend_test_completion_time;
  case CONVEYANCE_SELF_TEST:
  case CONVEYANCE_CAPTIVE_SELF_TEST:
    return (int) data->conveyance_test_completion_time;
  default:
    return 0;
  }
}

// This function tells you both about the ATA error log and the
// self-test error log capability (introduced in ATA-5).  The bit is
// poorly documented in the ATA/ATAPI standard.  Starting with ATA-6,
// SMART error logging is also indicated in bit 0 of DEVICE IDENTIFY
// word 84 and 87.  Top two bits must match the pattern 01. BEFORE
// ATA-6 these top two bits still had to match the pattern 01, but the
// remaining bits were reserved (==0).
int isSmartErrorLogCapable (struct ata_smart_values *data, struct ata_identify_device *identity){

  unsigned short word84=identity->command_set_extension;
  unsigned short word87=identity->csf_default;
  int isata6=identity->major_rev_num & (0x01<<6);
  int isata7=identity->major_rev_num & (0x01<<7);

  if ((isata6 || isata7) && (word84>>14) == 0x01 && (word84 & 0x01))
    return 1;
  
  if ((isata6 || isata7) && (word87>>14) == 0x01 && (word87 & 0x01))
    return 1;
  
  // otherwise we'll use the poorly documented capability bit
  return data->errorlog_capability & 0x01;
}

// See previous function.  If the error log exists then the self-test
// log should (must?) also exist.
int isSmartTestLogCapable (struct ata_smart_values *data, struct ata_identify_device *identity){

  unsigned short word84=identity->command_set_extension;
  unsigned short word87=identity->csf_default;
  int isata6=identity->major_rev_num & (0x01<<6);
  int isata7=identity->major_rev_num & (0x01<<7);

  if ((isata6 || isata7) && (word84>>14) == 0x01 && (word84 & 0x02))
    return 1;
  
  if ((isata6 || isata7) && (word87>>14) == 0x01 && (word87 & 0x02))
    return 1;


  // otherwise we'll use the poorly documented capability bit
    return data->errorlog_capability & 0x01;
}


int isGeneralPurposeLoggingCapable(struct ata_identify_device *identity){
  unsigned short word84=identity->command_set_extension;
  unsigned short word87=identity->csf_default;

  // If bit 14 of word 84 is set to one and bit 15 of word 84 is
  // cleared to zero, the contents of word 84 contains valid support
  // information. If not, support information is not valid in this
  // word.
  if ((word84>>14) == 0x01)
    // If bit 5 of word 84 is set to one, the device supports the
    // General Purpose Logging feature set.
    return (word84 & (0x01 << 5));
  
  // If bit 14 of word 87 is set to one and bit 15 of word 87 is
  // cleared to zero, the contents of words (87:85) contain valid
  // information. If not, information is not valid in these words.  
  if ((word87>>14) == 0x01)
    // If bit 5 of word 87 is set to one, the device supports
    // the General Purpose Logging feature set.
    return (word87 & (0x01 << 5));

  // not capable
  return 0;
}


// SMART self-test capability is also indicated in bit 1 of DEVICE
// IDENTIFY word 87 (if top two bits of word 87 match pattern 01).
// However this was only introduced in ATA-6 (but self-test log was in
// ATA-5).
int isSupportExecuteOfflineImmediate(struct ata_smart_values *data){
   return data->offline_data_collection_capability & 0x01;
}
// Note in the ATA-5 standard, the following bit is listed as "Vendor
// Specific".  So it may not be reliable. The only use of this that I
// have found is in IBM drives, where it is well-documented.  See for
// example page 170, section 13.32.1.18 of the IBM Travelstar 40GNX
// hard disk drive specifications page 164 Revision 1.1 22 Apr 2002.
int isSupportAutomaticTimer(struct ata_smart_values *data){
   return data->offline_data_collection_capability & 0x02;
}
int isSupportOfflineAbort(struct ata_smart_values *data){
   return data->offline_data_collection_capability & 0x04;
}
int isSupportOfflineSurfaceScan(struct ata_smart_values *data){
   return data->offline_data_collection_capability & 0x08;
}
int isSupportSelfTest (struct ata_smart_values *data){
   return data->offline_data_collection_capability & 0x10;
}
int isSupportConveyanceSelfTest(struct ata_smart_values *data){
   return data->offline_data_collection_capability & 0x20;
}
int isSupportSelectiveSelfTest(struct ata_smart_values *data){
   return data->offline_data_collection_capability & 0x40;
}



// Loop over all valid attributes.  If they are prefailure attributes
// and are at or below the threshold value, then return the ID of the
// first failing attribute found.  Return 0 if all prefailure
// attributes are in bounds.  The spec says "Bit 0
// -Pre-failure/advisory - If the value of this bit equals zero, an
// attribute value less than or equal to its corresponding attribute
// threshold indicates an advisory condition where the usage or age of
// the device has exceeded its intended design life period. If the
// value of this bit equals one, an atribute value less than or equal
// to its corresponding attribute threshold indicates a pre-failure
// condition where imminent loss of data is being predicted."


// onlyfailed=0 : are or were any age or prefailure attributes <= threshold
// onlyfailed=1:  are any prefailure attributes <= threshold now
int ataCheckSmart(struct ata_smart_values *data,
                  struct ata_smart_thresholds_pvt *thresholds,
                  int onlyfailed){
  int i;
  
  // loop over all attributes
  for (i=0; i<NUMBER_ATA_SMART_ATTRIBUTES; i++){

    // pointers to disk's values and vendor's thresholds
    struct ata_smart_attribute *disk=data->vendor_attributes+i;
    struct ata_smart_threshold_entry *thre=thresholds->thres_entries+i;
 
    // consider only valid attributes
    if (disk->id && thre->id){
      int failednow,failedever;
      
      failednow =disk->current <= thre->threshold;
      failedever=disk->worst   <= thre->threshold;
      
      if (!onlyfailed && failedever)
        return disk->id;
      
      if (onlyfailed && failednow && ATTRIBUTE_FLAGS_PREFAILURE(disk->flags))
        return disk->id;      
    }
  }
  return 0;
}



// This checks the n'th attribute in the attribute list, NOT the
// attribute with id==n.  If the attribute does not exist, or the
// attribute is > threshold, then returns zero.  If the attribute is
// <= threshold (failing) then we the attribute number if it is a
// prefail attribute.  Else we return minus the attribute number if it
// is a usage attribute.
int ataCheckAttribute(struct ata_smart_values *data,
                      struct ata_smart_thresholds_pvt *thresholds,
                      int n){
  struct ata_smart_attribute *disk;
  struct ata_smart_threshold_entry *thre;
  
  if (n<0 || n>=NUMBER_ATA_SMART_ATTRIBUTES || !data || !thresholds)
    return 0;
  
  // pointers to disk's values and vendor's thresholds
  disk=data->vendor_attributes+n;
  thre=thresholds->thres_entries+n;

  if (!disk || !thre)
    return 0;
  
  // consider only valid attributes, check for failure
  if (!disk->id || !thre->id || (disk->id != thre->id) || disk->current> thre->threshold)
    return 0;
  
  // We have found a failed attribute.  Return positive or negative? 
  if (ATTRIBUTE_FLAGS_PREFAILURE(disk->flags))
    return disk->id;
  else
    return -1*(disk->id);
}


// This routine prints the raw value of an attribute as a text string
// into out. It also returns this 48-bit number as a long long.  The
// array defs[] contains non-zero values if particular attributes have
// non-default interpretations.

int64_t ataPrintSmartAttribRawValue(char *out, 
                                    struct ata_smart_attribute *attribute,
                                    unsigned char *defs){
  int64_t rawvalue;
  unsigned word[3];
  int j;
  unsigned char select;
  
  // convert the six individual bytes to a long long (8 byte) integer.
  // This is the value that we'll eventually return.
  rawvalue = 0;
  for (j=0; j<6; j++) {
    // This looks a bit roundabout, but is necessary.  Don't
    // succumb to the temptation to use raw[j]<<(8*j) since under
    // the normal rules this will be promoted to the native type.
    // On a 32 bit machine this might then overflow.
    int64_t temp;
    temp = attribute->raw[j];
    temp <<= 8*j;
    rawvalue |= temp;
  }

  // convert quantities to three two-byte words
  for (j=0; j<3; j++){
    word[j] = attribute->raw[2*j+1];
    word[j] <<= 8;
    word[j] |= attribute->raw[2*j];
  }
  
  // if no data array, Attributes have default interpretations
  if (defs)
    select=defs[attribute->id];
  else
    select=0;

  // Print six one-byte quantities.
  if (select==253){
    for (j=0; j<5; j++)
      out+=sprintf(out, "%d ", attribute->raw[5-j]);
    out+=sprintf(out, "%d ", attribute->raw[0]);
    return rawvalue;
  } 
  
  // Print three two-byte quantities
  if (select==254){
    out+=sprintf(out, "%d %d %d", word[2], word[1], word[0]); 
    return rawvalue;
  } 
  
  // Print one six-byte quantity
  if (select==255){
    out+=sprintf(out, "%"PRIu64, rawvalue);
    return rawvalue;
  }

  // This switch statement is where we handle Raw attributes
  // that are stored in an unusual vendor-specific format,
  switch (attribute->id){
    // Spin-up time
  case 3:
    out+=sprintf(out, "%d", word[0]);
    // if second nonzero then it stores the average spin-up time
    if (word[1])
      out+=sprintf(out, " (Average %d)", word[1]);
    break;
    // Power on time
  case 9:
    if (select==1){
      // minutes
      int64_t tmp1=rawvalue/60;
      int64_t tmp2=rawvalue%60;
      out+=sprintf(out, "%"PRIu64"h+%02"PRIu64"m", tmp1, tmp2);
    }
    else if (select==3){
      // seconds
      int64_t hours=rawvalue/3600;
      int64_t minutes=(rawvalue-3600*hours)/60;
      int64_t seconds=rawvalue%60;
      out+=sprintf(out, "%"PRIu64"h+%02"PRIu64"m+%02"PRIu64"s", hours, minutes, seconds);
    }
    else if (select==4){
      // 30-second counter
      int64_t tmp1=rawvalue/120;
      int64_t tmp2=(rawvalue-120*tmp1)/2;
      out+=sprintf(out, "%"PRIu64"h+%02"PRIu64"m", tmp1, tmp2);
    }
    else
      // hours
      out+=sprintf(out, "%"PRIu64, rawvalue);  //stored in hours
    break;
   // Load unload cycles
  case 193:
    if (select==1){
      // loadunload
      long load  =attribute->raw[0] + (attribute->raw[1]<<8) + (attribute->raw[2]<<16);
      long unload=attribute->raw[3] + (attribute->raw[4]<<8) + (attribute->raw[5]<<16);
      out+=sprintf(out, "%lu/%lu", load, unload);
    }
    else
      // associated
      out+=sprintf(out, "%"PRIu64, rawvalue);
    break;
    // Temperature
  case 194:
    if (select==1){
      // ten times temperature in Celsius
      int deg=word[0]/10;
      int tenths=word[0]%10;
      out+=sprintf(out, "%d.%d", deg, tenths);
    }
    else if (select==2)
      // unknown attribute
      out+=sprintf(out, "%"PRIu64, rawvalue);
    else {
      out+=sprintf(out, "%d", word[0]);
      if (!(rawvalue==word[0])) {
        int min=word[1]<word[2]?word[1]:word[2];
        int max=word[1]>word[2]?word[1]:word[2];
        // The other bytes are in use. Try IBM's model
        out+=sprintf(out, " (Lifetime Min/Max %d/%d)", min, max);
      }
    }
    break;
  default:
    out+=sprintf(out, "%"PRIu64, rawvalue);
  }
  
  // Return the full value
  return rawvalue;
}


// Note some attribute names appear redundant because different
// manufacturers use different attribute IDs for an attribute with the
// same name.  The variable val should contain a non-zero value if a particular
// attributes has a non-default interpretation.
void ataPrintSmartAttribName(char *out, unsigned char id, unsigned char *definitions){
  char *name;
  unsigned char val;

  // If no data array, use default interpretations
  if (definitions)
    val=definitions[id];
  else
    val=0;

  switch (id){
    
  case 1:
    name="Raw_Read_Error_Rate";
    break;
  case 2:
    name="Throughput_Performance";
    break;
  case 3:
    name="Spin_Up_Time";
    break;
  case 4:
    name="Start_Stop_Count";
    break;
  case 5:
    name="Reallocated_Sector_Ct";
    break;
  case 6:
    name="Read_Channel_Margin";
    break;
  case 7:
    name="Seek_Error_Rate";
    break;
  case 8:
    name="Seek_Time_Performance";
    break;
  case 9:
    switch (val) {
    case 1:
      name="Power_On_Minutes";
      break;
    case 2:
      name="Temperature_Celsius";
      break;
    case 3:
      name="Power_On_Seconds";
      break;
    case 4:
      name="Power_On_Half_Minutes";
      break;
    default:
      name="Power_On_Hours";
      break;
    }
    break;
  case 10:
    name="Spin_Retry_Count";
    break;
  case 11:
    name="Calibration_Retry_Count";
    break;
  case 12:
    name="Power_Cycle_Count";
    break;
  case 13:
    name="Read_Soft_Error_Rate";
    break;
  case 190:
    // Western Digital uses this for temperature.
    // It's identical to Attribute 194 except that it
    // has a failure threshold set to correspond to the
    // max allowed operating temperature of the drive, which 
    // is typically 55C.  So if this attribute has failed
    // in the past, it indicates that the drive temp exceeded
    // 55C sometime in the past.
    name="Temperature_Celsius";
    break;
  case 191:
    name="G-Sense_Error_Rate";
    break;
  case 192:
    switch (val) {
    case 1:
      // Fujitsu
      name="Emergency_Retract_Cycle_Ct";
      break;
    default:
      name="Power-Off_Retract_Count";
      break;
    }
    break;
  case 193:
    name="Load_Cycle_Count";
    break;
  case 194:
    switch (val){
    case 1:
      // Samsung SV1204H with RK100-13 firmware
      name="Temperature_Celsius_x10";
      break;
    case 2:
      // for disks with no temperature Attribute
      name="Unknown_Attribute";
      break;
    default:
      name="Temperature_Celsius";
      break;
    }
    break;
  case 195:
    // Fujitsu name="ECC_On_The_Fly_Count";
    name="Hardware_ECC_Recovered";
    break;
  case 196:
    name="Reallocated_Event_Count";
    break;
  case 197:
    name="Current_Pending_Sector";
    break;
  case 198:
    switch (val){
    case 1:
      // Fujitsu
      name="Off-line_Scan_UNC_Sector_Ct";
      break;
    default:
      name="Offline_Uncorrectable";
      break;
    }
    break;
  case 199:
    name="UDMA_CRC_Error_Count";
    break;
  case 200:
    switch (val) {
    case 1:
      // Fujitsu MHS2020AT
      name="Write_Error_Count";
      break;
    default:
      // Western Digital
      name="Multi_Zone_Error_Rate";
      break;
    }
    break;
  case 201:
    switch (val) {
    case 1:
      // Fujitsu
      name="Detected_TA_Count";
      break;
    default:
      name="Soft_Read_Error_Rate";
      break;
    }
    break;
  case 202:
    // Fujitsu
    name="TA_Increase_Count";
    // Maxtor: Data Address Mark Errors
    break;
  case 203:
    // Fujitsu
    name="Run_Out_Cancel";
    // Maxtor: ECC Errors
    break;
  case 204:
    // Fujitsu
    name="Shock_Count_Write_Opern";
    // Maxtor: Soft ECC Correction
    break;
  case 205:
    // Fujitsu
    name="Shock_Rate_Write_Opern";
    // Maxtor: Thermal Aspirates
    break;
  case 206:
    // Fujitsu
    name="Flying_Height";
    break;
  case 207:
    // Maxtor
    name="Spin_High_Current";
    break;
  case 208:
    // Maxtor
    name="Spin_Buzz";
    break;
  case 209:
    // Maxtor
    name="Offline_Seek_Performnce";
    break;
  case 220:
    switch (val) {
    case 1:
      name="Temperature_Celsius";
      break;
    default:
      name="Disk_Shift";
      break;
    }
    break;
  case 221:
    name="G-Sense_Error_Rate";
    break;
  case 222:
    name="Loaded_Hours";
    break;
  case 223:
    name="Load_Retry_Count";
    break;
  case 224:
    name="Load_Friction";
    break;
  case 225:
    name="Load_Cycle_Count";
    break;
  case 226:
    name="Load-in_Time";
    break;
  case 227:
    name="Torq-amp_Count";
    break;
  case 228:
    name="Power-off_Retract_Count";
    break;
  case 230:
    // seen in IBM DTPA-353750
    name="Head_Amplitude";
    break;
  case 231:
    name="Temperature_Celsius";
    break;
  case 240:
    name="Head_Flying_Hours";
    break;
  case 250:
    name="Read_Error_Retry_Rate";
    break;
  default:
    name="Unknown_Attribute";
    break;
  }
  sprintf(out,"%3hu %s",(short int)id,name);
  return;
}

// Returns raw value of Attribute with ID==id. This will be in the
// range 0 to 2^48-1 inclusive.  If the Attribute does not exist,
// return -1.
int64_t ATAReturnAttributeRawValue(unsigned char id, struct ata_smart_values *data) {
  int i;

  // valid Attribute IDs are in the range 1 to 255 inclusive.
  if (!id || !data)
    return -1;
  
  // loop over Attributes to see if there is one with the desired ID
  for (i=0; i<NUMBER_ATA_SMART_ATTRIBUTES; i++) {
    struct ata_smart_attribute *ap = data->vendor_attributes + i;
    if (ap->id == id) {
      // we've found the desired Attribute.  Return its value
      int64_t rawvalue=0;
      int j;

      for (j=0; j<6; j++) {
        // This looks a bit roundabout, but is necessary.  Don't
        // succumb to the temptation to use raw[j]<<(8*j) since under
        // the normal rules this will be promoted to the native type.
        // On a 32 bit machine this might then overflow.
        int64_t temp;
        temp = ap->raw[j];
        temp <<= 8*j;
        rawvalue |= temp;
      } // loop over j
      return rawvalue;
    } // found desired Attribute
  } // loop over Attributes
  
  // fall-through: no such Attribute found
  return -1;
}

// Return Temperature Attribute raw value selected according to possible
// non-default interpretations. If the Attribute does not exist, return 0
unsigned char ATAReturnTemperatureValue(/*const*/ struct ata_smart_values *data, const unsigned char *defs){
  int i;
  for (i = 0; i < 3; i++) {
    static const unsigned char ids[3] = {194, 9, 220};
    unsigned char id = ids[i];
    unsigned char select = (defs ? defs[id] : 0);
    int64_t raw; unsigned temp;
    if (!(   (id == 194 && select <= 1)   // ! -v 194,unknown
          || (id == 9 && select == 2)     // -v 9,temp
          || (id == 220 && select == 1))) // -v 220,temp
      continue;
    raw = ATAReturnAttributeRawValue(id, data);
    if (raw < 0)
      continue;
    temp = (unsigned short)raw; // ignore possible min/max values in high words
    if (id == 194 && select == 1) // -v 194,10xCelsius
      temp = (temp+5) / 10;
    if (!(0 < temp && temp <= 255))
      continue;
    return temp;
  }
  // No valid attribute found
  return 0;
}