Process.c

/*
htop - Process.c
(C) 2004-2006 Hisham H. Muhammad
Released under the GNU GPL, see the COPYING file
in the source distribution for its full text.
*/

#define _GNU_SOURCE
#include "ProcessList.h"
#include "Object.h"
#include "CRT.h"
#include "String.h"
#include "Process.h"
#include "RichString.h"

#include "debug.h"

#include <stdio.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <sys/param.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <signal.h>
#include <string.h>
#include <stdbool.h>
#include <pwd.h>
#include <sched.h>

// This works only with glibc 2.1+. On earlier versions
// the behavior is similar to have a hardcoded page size.
#ifndef PAGE_SIZE
#define PAGE_SIZE ( sysconf(_SC_PAGESIZE) )
#endif
#define PAGE_SIZE_KB ( PAGE_SIZE / ONE_K )

#define PROCESS_COMM_LEN 300

/*{

typedef enum ProcessField_ {
   PID = 1, COMM, STATE, PPID, PGRP, SESSION, TTY_NR, TPGID, FLAGS, MINFLT, CMINFLT, MAJFLT, CMAJFLT, UTIME,
   STIME, CUTIME, CSTIME, PRIORITY, NICE, ITREALVALUE, STARTTIME, VSIZE, RSS, RLIM, STARTCODE, ENDCODE,
   STARTSTACK, KSTKESP, KSTKEIP, SIGNAL, BLOCKED, SSIGIGNORE, SIGCATCH, WCHAN, NSWAP, CNSWAP, EXIT_SIGNAL,
   PROCESSOR, M_SIZE, M_RESIDENT, M_SHARE, M_TRS, M_DRS, M_LRS, M_DT, ST_UID, PERCENT_CPU, PERCENT_MEM,
   USER, TIME, NLWP, TGID,
   #ifdef HAVE_OPENVZ
   CTID, VPID,
   #endif
   #ifdef HAVE_VSERVER
   VXID,
   #endif
   #ifdef HAVE_TASKSTATS
   RCHAR, WCHAR, SYSCR, SYSCW, RBYTES, WBYTES, CNCLWB, IO_READ_RATE, IO_WRITE_RATE, IO_RATE,
   #endif
   LAST_PROCESSFIELD
} ProcessField;

struct ProcessList_;

typedef struct Process_ {
   Object super;

   struct ProcessList_ *pl;
   bool updated;

   unsigned int pid;
   char* comm;
   int indent;
   char state;
   bool tag;
   unsigned int ppid;
   unsigned int pgrp;
   unsigned int session;
   unsigned int tty_nr;
   unsigned int tgid;
   int tpgid;
   unsigned long int flags;
   #ifdef DEBUG
   unsigned long int minflt;
   unsigned long int cminflt;
   unsigned long int majflt;
   unsigned long int cmajflt;
   #endif
   unsigned long int utime;
   unsigned long int stime;
   long int cutime;
   long int cstime;
   long int priority;
   long int nice;
   long int nlwp;
   #ifdef DEBUG
   long int itrealvalue;
   unsigned long int starttime;
   unsigned long int vsize;
   long int rss;
   unsigned long int rlim;
   unsigned long int startcode;
   unsigned long int endcode;
   unsigned long int startstack;
   unsigned long int kstkesp;
   unsigned long int kstkeip;
   unsigned long int signal;
   unsigned long int blocked;
   unsigned long int sigignore;
   unsigned long int sigcatch;
   unsigned long int wchan;
   unsigned long int nswap;
   unsigned long int cnswap;
   #endif
   int exit_signal;
   int processor;
   int m_size;
   int m_resident;
   int m_share;
   int m_trs;
   int m_drs;
   int m_lrs;
   int m_dt;
   uid_t st_uid;
   float percent_cpu;
   float percent_mem;
   char* user;
   #ifdef HAVE_OPENVZ
   unsigned int ctid;
   unsigned int vpid;
   #endif
   #ifdef HAVE_VSERVER
   unsigned int vxid;
   #endif
   #ifdef HAVE_TASKSTATS
   unsigned long long io_rchar;
   unsigned long long io_wchar;
   unsigned long long io_syscr;
   unsigned long long io_syscw;
   unsigned long long io_read_bytes;
   unsigned long long io_write_bytes;
   unsigned long long io_cancelled_write_bytes;
   double io_rate_read_bps;
   unsigned long long io_rate_read_time;
   double io_rate_write_bps;
   unsigned long long io_rate_write_time;   
   #endif
} Process;

}*/

#ifdef DEBUG
char *PROCESS_CLASS = "Process";
#else
#define PROCESS_CLASS NULL
#endif

char *Process_fieldNames[] = {
  "", "PID", "Command", "STATE", "PPID", "PGRP", "SESSION",
  "TTY_NR", "TPGID", "FLAGS", "MINFLT", "CMINFLT", "MAJFLT", "CMAJFLT",
  "UTIME", "STIME", "CUTIME", "CSTIME", "PRIORITY", "NICE", "ITREALVALUE",
  "STARTTIME", "VSIZE", "RSS", "RLIM", "STARTCODE", "ENDCODE",
  "STARTSTACK",
  "KSTKESP", "KSTKEIP", "SIGNAL", "BLOCKED", "SIGIGNORE", "SIGCATCH",
  "WCHAN",
  "NSWAP", "CNSWAP", "EXIT_SIGNAL", "PROCESSOR", "M_SIZE", "M_RESIDENT",
  "M_SHARE",
  "M_TRS", "M_DRS", "M_LRS", "M_DT", "ST_UID", "PERCENT_CPU",
  "PERCENT_MEM",
  "USER", "TIME", "NLWP", "TGID",
#ifdef HAVE_OPENVZ
  "CTID", "VPID",
#endif
#ifdef HAVE_VSERVER
  "VXID",
#endif
#ifdef HAVE_TASKSTATS
  "RCHAR", "WCHAR", "SYSCR", "SYSCW", "RBYTES", "WBYTES", "CNCLWB",
  "IO_READ_RATE", "IO_WRITE_RATE", "IO_RATE",
#endif
  "*** report bug! ***"
};

char *Process_fieldTitles[] = {
  "", "  PID ", "Command ", "S ", " PPID ", " PGRP ", " SESN ",
  "  TTY ", "TPGID ", "- ", "- ", "- ", "- ", "- ",
  " UTIME+  ", " STIME+  ", "- ", "- ", "PRI ", " NI ", "- ",
  "START ", "- ", "- ", "- ", "- ", "- ", "- ",
  "- ", "- ", "- ", "- ", "- ", "- ", "- ",
  "- ", "- ", "- ", "CPU ", " VIRT ", "  RES ", "  SHR ",
  " CODE ", " DATA ", " LIB ", " DIRTY ", " UID ", "CPU% ", "MEM% ",
  "USER     ", "  TIME+  ", "NLWP ", " TGID ",
#ifdef HAVE_OPENVZ
  " CTID ", " VPID ",
#endif
#ifdef HAVE_VSERVER
  " VXID ",
#endif
#ifdef HAVE_TASKSTATS
  "   RD_CHAR ", "   WR_CHAR ", "   RD_SYSC ", "   WR_SYSC ",
  "     IO_RD ", "     IO_WR ", " IO_CANCEL ",
  " IORR ", " IOWR ", "   IO ",
#endif
};

static int Process_getuid = -1;

#define ONE_K 1024
#define ONE_M (ONE_K * ONE_K)
#define ONE_G (ONE_M * ONE_K)

static void
Process_printLargeNumber( Process * this, RichString * str,
                          unsigned long number ) {
  char buffer[11];
  int len;
  if ( number >= ( 10 * ONE_M ) ) {
    len = snprintf( buffer, 10, "%3.1fG ", ( float ) number / ONE_M );
    RichString_appendn( str, CRT_colors[LARGE_NUMBER], buffer, len );
  }
  else if ( number >= ( 100000 ) ) {
    len = snprintf( buffer, 10, "%4ldM ", number / ONE_K );
    int attr = this->pl->highlightMegabytes ? CRT_colors[PROCESS_MEGABYTES]
        : CRT_colors[PROCESS];
    RichString_appendn( str, attr, buffer, len );
  }
  else if ( this->pl->highlightMegabytes && number >= 1000 ) {
    len = snprintf( buffer, 10, "%2ld", number / 1000 );
    RichString_appendn( str, CRT_colors[PROCESS_MEGABYTES], buffer, len );
    number %= 1000;
    len = snprintf( buffer, 10, "%03ld ", number );
    RichString_appendn( str, CRT_colors[PROCESS], buffer, len );
  }
  else {
    len = snprintf( buffer, 10, "%5ld ", number );
    RichString_appendn( str, CRT_colors[PROCESS], buffer, len );
  }
}

static double jiffy = 0.0;

static void
Process_printTime( RichString * str, unsigned long t ) {
  if ( jiffy == 0.0 )
    jiffy = sysconf( _SC_CLK_TCK );
  double jiffytime = 1.0 / jiffy;

  double realTime = t * jiffytime;
  int iRealTime = ( int ) realTime;

  int hours = iRealTime / 3600;
  int minutes = ( iRealTime / 60 ) % 60;
  int seconds = iRealTime % 60;
  int hundredths = ( realTime - iRealTime ) * 100;
  char buffer[11];
  if ( hours ) {
    snprintf( buffer, 10, "%2dh", hours );
    RichString_append( str, CRT_colors[LARGE_NUMBER], buffer );
    snprintf( buffer, 10, "%02d:%02d ", minutes, seconds );
  }
  else {
    snprintf( buffer, 10, "%2d:%02d.%02d ", minutes, seconds, hundredths );
  }
  RichString_append( str, CRT_colors[DEFAULT_COLOR], buffer );
}

static inline void
Process_writeCommand( Process * this, int attr, int baseattr,
                      RichString * str ) {
  int start = str->len;
  RichString_append( str, attr, this->comm );
  if ( this->pl->highlightBaseName ) {
    int finish = str->len - 1;
    int space = RichString_findChar( str, ' ', start );
    if ( space != -1 )
      finish = space - 1;
    for ( ;; ) {
      int slash = RichString_findChar( str, '/', start );
      if ( slash == -1 || slash > finish )
        break;
      start = slash + 1;
    }
    RichString_setAttrn( str, baseattr, start, finish );
  }
}

static inline void
Process_outputRate( Process * this, RichString * str, int attr,
                    char *buffer, int n, double rate ) {
  rate = rate / 1024;
  if ( rate < 0.01 )
    snprintf( buffer, n, "    0 " );
  else if ( rate <= 10 )
    snprintf( buffer, n, "%5.2f ", rate );
  else if ( rate <= 100 )
    snprintf( buffer, n, "%5.1f ", rate );
  else {
    Process_printLargeNumber( this, str, rate );
    return;
  }
  RichString_append( str, attr, buffer );
}

static void
Process_writeField( Process * this, RichString * str, ProcessField field ) {
  char buffer[PROCESS_COMM_LEN];
  int attr = CRT_colors[DEFAULT_COLOR];
  int baseattr = CRT_colors[PROCESS_BASENAME];
  int n = PROCESS_COMM_LEN;

  switch ( field ) {
  case PID:
    snprintf( buffer, n, "%5u ", this->pid );
    break;
  case PPID:
    snprintf( buffer, n, "%5u ", this->ppid );
    break;
  case PGRP:
    snprintf( buffer, n, "%5u ", this->pgrp );
    break;
  case SESSION:
    snprintf( buffer, n, "%5u ", this->session );
    break;
  case TTY_NR:
    snprintf( buffer, n, "%5u ", this->tty_nr );
    break;
  case TGID:
    snprintf( buffer, n, "%5u ", this->tgid );
    break;
  case TPGID:
    snprintf( buffer, n, "%5d ", this->tpgid );
    break;
  case PROCESSOR:
    snprintf( buffer, n, "%3d ", this->processor + 1 );
    break;
  case NLWP:
    snprintf( buffer, n, "%4ld ", this->nlwp );
    break;
  case STARTTIME:
    snprintf(buffer, n, "%s ", this->starttime_show);
    break;
  case COMM:{
      if ( this->pl->highlightThreads
           && ( this->pid != this->tgid || this->m_size == 0 ) ) {
        attr = CRT_colors[PROCESS_THREAD];
        baseattr = CRT_colors[PROCESS_THREAD_BASENAME];
      }
      if ( !this->pl->treeView || this->indent == 0 ) {
        Process_writeCommand( this, attr, baseattr, str );
        return;
      }
      else {
        char *buf = buffer;
        int maxIndent = 0;
        for ( int i = 0; i < 32; i++ )
          if ( this->indent & ( 1 << i ) )
            maxIndent = i + 1;
        for ( int i = 0; i < maxIndent - 1; i++ ) {
          if ( this->indent & ( 1 << i ) )
            snprintf( buf, n, " |  " );
          else
            snprintf( buf, n, "    " );
          buf += 4;
          n -= 4;
        }
        if ( this->pl->direction == 1 )
          snprintf( buf, n, " `- " );
        else
          snprintf( buf, n, " ,- " );
        RichString_append( str, CRT_colors[PROCESS_TREE], buffer );
        Process_writeCommand( this, attr, baseattr, str );
        return;
      }
    }
  case STATE:{
      snprintf( buffer, n, "%c ", this->state );
      attr = this->state == 'R' ? CRT_colors[PROCESS_R_STATE]
          : attr;
      break;
    }
  case PRIORITY:{
      if ( this->priority == -100 )
        snprintf( buffer, n, " RT " );
      else
        snprintf( buffer, n, "%3ld ", this->priority );
      break;
    }
  case NICE:{
      snprintf( buffer, n, "%3ld ", this->nice );
      attr = this->nice < 0 ? CRT_colors[PROCESS_HIGH_PRIORITY]
          : this->nice > 0 ? CRT_colors[PROCESS_LOW_PRIORITY]
          : attr;
      break;
    }
  case M_DRS:
    Process_printLargeNumber( this, str, this->m_drs * PAGE_SIZE_KB );
    return;
  case M_DT:
    Process_printLargeNumber( this, str, this->m_dt * PAGE_SIZE_KB );
    return;
  case M_LRS:
    Process_printLargeNumber( this, str, this->m_lrs * PAGE_SIZE_KB );
    return;
  case M_TRS:
    Process_printLargeNumber( this, str, this->m_trs * PAGE_SIZE_KB );
    return;
  case M_SIZE:
    Process_printLargeNumber( this, str, this->m_size * PAGE_SIZE_KB );
    return;
  case M_RESIDENT:
    Process_printLargeNumber( this, str, this->m_resident * PAGE_SIZE_KB );
    return;
  case M_SHARE:
    Process_printLargeNumber( this, str, this->m_share * PAGE_SIZE_KB );
    return;
  case ST_UID:
    snprintf( buffer, n, "%4d ", this->st_uid );
    break;
  case USER:{
      if ( Process_getuid != this->st_uid )
        attr = CRT_colors[PROCESS_SHADOW];
      if ( this->user ) {
        snprintf( buffer, n, "%-8s ", this->user );
      }
      else {
        snprintf( buffer, n, "%-8d ", this->st_uid );
      }
      if ( buffer[8] != '\0' ) {
        buffer[8] = ' ';
        buffer[9] = '\0';
      }
      break;
    }
  case UTIME:
    Process_printTime( str, this->utime );
    return;
  case STIME:
    Process_printTime( str, this->stime );
    return;
  case CUTIME:
    Process_printTime( str, this->cutime );
    return;
  case CSTIME:
    Process_printTime( str, this->cstime );
    return;
  case TIME:
    Process_printTime( str, this->utime + this->stime );
    return;
  case PERCENT_CPU:{
      if ( this->percent_cpu > 999.9 ) {
        snprintf( buffer, n, "%4d ", ( unsigned int ) this->percent_cpu );
      }
      else if ( this->percent_cpu > 99.9 ) {
        snprintf( buffer, n, "%3d. ", ( unsigned int ) this->percent_cpu );
      }
      else {
        snprintf( buffer, n, "%4.1f ", this->percent_cpu );
      }
      break;
    }
  case PERCENT_MEM:{
      if ( this->percent_mem > 99.9 ) {
        snprintf( buffer, n, "100. " );
      }
      else {
        snprintf( buffer, n, "%4.1f ", this->percent_mem );
      }
      break;
    }
#ifdef HAVE_OPENVZ
  case CTID:
    snprintf( buffer, n, "%5u ", this->ctid );
    break;
  case VPID:
    snprintf( buffer, n, "%5u ", this->vpid );
    break;
#endif
#ifdef HAVE_VSERVER
  case VXID:
    snprintf( buffer, n, "%5u ", this->vxid );
    break;
#endif
#ifdef HAVE_TASKSTATS
  case RCHAR:
    snprintf( buffer, n, "%10llu ", this->io_rchar );
    break;
  case WCHAR:
    snprintf( buffer, n, "%10llu ", this->io_wchar );
    break;
  case SYSCR:
    snprintf( buffer, n, "%10llu ", this->io_syscr );
    break;
  case SYSCW:
    snprintf( buffer, n, "%10llu ", this->io_syscw );
    break;
  case RBYTES:
    snprintf( buffer, n, "%10llu ", this->io_read_bytes );
    break;
  case WBYTES:
    snprintf( buffer, n, "%10llu ", this->io_write_bytes );
    break;
  case CNCLWB:
    snprintf( buffer, n, "%10llu ", this->io_cancelled_write_bytes );
    break;
  case IO_READ_RATE:
    Process_outputRate( this, str, attr, buffer, n,
                        this->io_rate_read_bps );
    return;
  case IO_WRITE_RATE:
    Process_outputRate( this, str, attr, buffer, n,
                        this->io_rate_write_bps );
    return;
  case IO_RATE:
    Process_outputRate( this, str, attr, buffer, n,
                        this->io_rate_read_bps + this->io_rate_write_bps );
    return;
#endif

  default:
    snprintf( buffer, n, "- " );
  }
  RichString_append( str, attr, buffer );
}

static void
Process_display( Object * cast, RichString * out ) {
  Process *this = ( Process * ) cast;
  ProcessField *fields = this->pl->fields;
  RichString_init( out );
  for ( int i = 0; fields[i]; i++ )
    Process_writeField( this, out, fields[i] );
  if ( this->pl->shadowOtherUsers && this->st_uid != Process_getuid )
    RichString_setAttr( out, CRT_colors[PROCESS_SHADOW] );
  if ( this->tag == true )
    RichString_setAttr( out, CRT_colors[PROCESS_TAG] );
  assert( out->len > 0 );
}

void
Process_delete( Object * cast ) {
  Process *this = ( Process * ) cast;
  assert( this != NULL );
  if ( this->comm )
    free( this->comm );
  free( this );
}

Process *
Process_new( struct ProcessList_ *pl ) {
  Process *this = calloc( sizeof( Process ), 1 );
  Object_setClass( this, PROCESS_CLASS );
  ( ( Object * ) this )->display = Process_display;
  ( ( Object * ) this )->delete = Process_delete;
  this->pid = 0;
  this->pl = pl;
  this->tag = false;
  this->updated = false;
  this->utime = 0;
  this->stime = 0;
  this->comm = NULL;
  this->indent = 0;
  if ( Process_getuid == -1 )
    Process_getuid = getuid(  );
  return this;
}

Process *
Process_clone( Process * this ) {
  Process *clone = malloc( sizeof( Process ) );
#if HAVE_TASKSTATS
  this->io_rchar = 0;
  this->io_wchar = 0;
  this->io_syscr = 0;
  this->io_syscw = 0;
  this->io_read_bytes = 0;
  this->io_rate_read_bps = 0;
  this->io_rate_read_time = 0;
  this->io_write_bytes = 0;
  this->io_rate_write_bps = 0;
  this->io_rate_write_time = 0;
  this->io_cancelled_write_bytes = 0;
#endif
  memcpy( clone, this, sizeof( Process ) );
  this->comm = NULL;
  this->pid = 0;
  return clone;
}

void
Process_toggleTag( Process * this ) {
  this->tag = this->tag == true ? false : true;
}

bool
Process_setPriority( Process * this, int priority ) {
  if ( Process_getuid == 0 || Process_getuid == this->st_uid ) {
    int old_prio = getpriority( PRIO_PROCESS, this->pid );
    int err = setpriority( PRIO_PROCESS, this->pid, priority );
    if ( err == 0 && old_prio != getpriority( PRIO_PROCESS, this->pid ) ) {
      this->nice = priority;
    }
    return ( err == 0 );
  }
  else
    return false;
}

unsigned long
Process_getAffinity( Process * this ) {
  return 0;
}

bool
Process_setAffinity( Process * this, unsigned long mask ) {
  return true;
}

void
Process_sendSignal( Process * this, int signal ) {
    if ( Process_getuid == 0 || Process_getuid == this->st_uid )
        kill( this->pid, signal );
}

int
Process_pidCompare( const void *v1, const void *v2 ) {
  Process *p1 = ( Process * ) v1;
  Process *p2 = ( Process * ) v2;
  return ( p1->pid - p2->pid );
}

int
Process_compare( const void *v1, const void *v2 ) {
  Process *p1, *p2;
  ProcessList *pl = ( ( Process * ) v1 )->pl;
  if ( pl->direction == 1 ) {
    p1 = ( Process * ) v1;
    p2 = ( Process * ) v2;
  }
  else {
    p2 = ( Process * ) v1;
    p1 = ( Process * ) v2;
  }
  long long diff;
  switch ( pl->sortKey ) {
  case PID:
    return ( p1->pid - p2->pid );
  case PPID:
    return ( p1->ppid - p2->ppid );
  case USER:
    return strcmp( p1->user ? p1->user : "", p2->user ? p2->user : "" );
  case PRIORITY:
    return ( p1->priority - p2->priority );
  case PROCESSOR:
    return ( p1->processor - p2->processor );
  case SESSION:
    return ( p1->session - p2->session );
  case STATE:
    return ( p1->state - p2->state );
  case NICE:
    return ( p1->nice - p2->nice );
  case M_DRS:
    return ( p2->m_drs - p1->m_drs );
  case M_DT:
    return ( p2->m_dt - p1->m_dt );
  case M_LRS:
    return ( p2->m_lrs - p1->m_lrs );
  case M_TRS:
    return ( p2->m_trs - p1->m_trs );
  case M_SIZE:
    return ( p2->m_size - p1->m_size );
  case M_RESIDENT:
    return ( p2->m_resident - p1->m_resident );
  case M_SHARE:
    return ( p2->m_share - p1->m_share );
  case PERCENT_CPU:
    return ( p2->percent_cpu > p1->percent_cpu ? 1 : -1 );
  case PERCENT_MEM:
    return ( p2->m_resident - p1->m_resident );
  case UTIME:
    return ( p2->utime - p1->utime );
  case STIME:
    return ( p2->stime - p1->stime );
  case TIME:
    return ( ( p2->utime + p2->stime ) - ( p1->utime + p1->stime ) );
  case COMM:
    return strcmp( p1->comm, p2->comm );
  case NLWP:
    return ( p1->nlwp - p2->nlwp );
  case STARTTIME:
    if (p1->starttime.tv_sec == p2->starttime.tv_sec)
        return p1->starttime.tv_usec - p2->starttime.tv_usec;
    else
        return p1->starttime.tv_sec - p2->starttime.tv_sec;
#ifdef HAVE_OPENVZ
  case CTID:
    return ( p1->ctid - p2->ctid );
  case VPID:
    return ( p1->vpid - p2->vpid );
#endif
#ifdef HAVE_VSERVER
  case VXID:
    return ( p1->vxid - p2->vxid );
#endif
#ifdef HAVE_TASKSTATS
  case RCHAR:
    diff = p2->io_rchar - p1->io_rchar;
    goto test_diff;
  case WCHAR:
    diff = p2->io_wchar - p1->io_wchar;
    goto test_diff;
  case SYSCR:
    diff = p2->io_syscr - p1->io_syscr;
    goto test_diff;
  case SYSCW:
    diff = p2->io_syscw - p1->io_syscw;
    goto test_diff;
  case RBYTES:
    diff = p2->io_read_bytes - p1->io_read_bytes;
    goto test_diff;
  case WBYTES:
    diff = p2->io_write_bytes - p1->io_write_bytes;
    goto test_diff;
  case CNCLWB:
    diff = p2->io_cancelled_write_bytes - p1->io_cancelled_write_bytes;
    goto test_diff;
  case IO_READ_RATE:
    diff = p2->io_rate_read_bps - p1->io_rate_read_bps;
    goto test_diff;
  case IO_WRITE_RATE:
    diff = p2->io_rate_write_bps - p1->io_rate_write_bps;
    goto test_diff;
  case IO_RATE:
    diff =
        ( p2->io_rate_read_bps + p2->io_rate_write_bps ) -
        ( p1->io_rate_read_bps + p1->io_rate_write_bps );
    goto test_diff;
#endif

  default:
    return ( p1->pid - p2->pid );
  }
test_diff:
  return ( diff > 0 ) ? 1 : ( diff < 0 ? -1 : 0 );
}