output.c

linux下获取一些环境信息的代码

  case  2: return snprintf(outbuf, COLWID, "RR");  // SCHED_RR
  case  3: return snprintf(outbuf, COLWID, "B");   // SCHED_BATCH? (will be "B")
  case  4: return snprintf(outbuf, COLWID, "#4");  // SCHED_ISO? (Con Kolivas)
  case  5: return snprintf(outbuf, COLWID, "#5");  //
  case  8: return snprintf(outbuf, COLWID, "#8");  //
  default: return snprintf(outbuf, COLWID, "?");   // unknown value
  }
}
// Based on "type", FreeBSD would do:
//    REALTIME  "real:%u", prio
//    NORMAL    "normal"
//    IDLE      "idle:%u", prio
//    default   "%u:%u", type, prio
// We just print the priority, and have other keywords for type.
static int pr_rtprio(char *restrict const outbuf, const proc_t *restrict const pp){
  if(pp->sched==0 || pp->sched==-1) return snprintf(outbuf, COLWID, "-");
  return snprintf(outbuf, COLWID, "%ld", pp->rtprio);
}
static int pr_sched(char *restrict const outbuf, const proc_t *restrict const pp){
  if(pp->sched==-1) return snprintf(outbuf, COLWID, "-");
  return snprintf(outbuf, COLWID, "%ld", pp->sched);
}

////////////////////////////////////////////////////////////////////////////////

static int pr_wchan(char *restrict const outbuf, const proc_t *restrict const pp){
/*
 * Unix98 says "blank if running" and also "no blanks"! :-(
 * Unix98 also says to use '-' if something is meaningless.
 * Digital uses both '*' and '-', with undocumented differences.
 * (the '*' for -1 (rare) and the '-' for 0)
 * Sun claims to use a blank AND use '-', in the same man page.
 * Perhaps "blank" should mean '-'.
 *
 * AIX uses '-' for running processes, the location when there is
 * only one thread waiting in the kernel, and '*' when there is
 * more than one thread waiting in the kernel.
 *
 * The output should be truncated to maximal columns width -- overflow
 * is not supported for the "wchan".
 */
  const char *w;
  size_t len;
  if(!(pp->wchan & 0xffffff)) return memcpy(outbuf,"-",2),1;
  if(wchan_is_number) return snprintf(outbuf, COLWID, "%x", (unsigned)(pp->wchan) & 0xffffffu);
  w = lookup_wchan(pp->wchan, pp->XXXID);
  len = strlen(w);
  if(len>max_rightward) len=max_rightward;
  memcpy(outbuf, w, len);
  outbuf[len] = '\0';
  return len;
}

static int pr_wname(char *restrict const outbuf, const proc_t *restrict const pp){
/* SGI's IRIX always uses a number for "wchan", so "wname" is provided too.
 *
 * We use '-' for running processes, the location when there is
 * only one thread waiting in the kernel, and '*' when there is
 * more than one thread waiting in the kernel.
 *
 * The output should be truncated to maximal columns width -- overflow
 * is not supported for the "wchan".
 */
  const char *w;
  size_t len;
  if(!(pp->wchan & 0xffffff)) return memcpy(outbuf,"-",2),1;
  w = lookup_wchan(pp->wchan, pp->XXXID);
  len = strlen(w);
  if(len>max_rightward) len=max_rightward;
  memcpy(outbuf, w, len);
  outbuf[len] = '\0';
  return len;
}

static int pr_nwchan(char *restrict const outbuf, const proc_t *restrict const pp){
  if(!(pp->wchan & 0xffffff)) return memcpy(outbuf,"-",2),1;
  return snprintf(outbuf, COLWID, "%x", (unsigned)(pp->wchan) & 0xffffffu);
}

/* Terrible trunctuation, like BSD crap uses: I999 J999 K999 */
/* FIXME: disambiguate /dev/tty69 and /dev/pts/69. */
static int pr_tty4(char *restrict const outbuf, const proc_t *restrict const pp){
/* snprintf(outbuf, COLWID, "%02x:%02x", pp->tty>>8, pp->tty&0xff); */
  return dev_to_tty(outbuf, 4, pp->tty, pp->XXXID, ABBREV_DEV|ABBREV_TTY|ABBREV_PTS);
}

/* Unix98: format is unspecified, but must match that used by who(1). */
static int pr_tty8(char *restrict const outbuf, const proc_t *restrict const pp){
/* snprintf(outbuf, COLWID, "%02x:%02x", pp->tty>>8, pp->tty&0xff); */
  return dev_to_tty(outbuf, COLWID, pp->tty, pp->XXXID, ABBREV_DEV);
}

#if 0
/* This BSD state display may contain spaces, which is illegal. */
static int pr_oldstate(char *restrict const outbuf, const proc_t *restrict const pp){
    return snprintf(outbuf, COLWID, "%s", status(pp));
}
#endif

// This state display is Unix98 compliant and has lots of info like BSD.
static int pr_stat(char *restrict const outbuf, const proc_t *restrict const pp){
    int end = 0;
    outbuf[end++] = pp->state;
//  if(pp->rss==0 && pp->state!='Z')  outbuf[end++] = 'W'; // useless "swapped out"
    if(pp->nice < 0)                  outbuf[end++] = '<';
    if(pp->nice > 0)                  outbuf[end++] = 'N';
// In this order, NetBSD would add:
//     traced   'X'
//     systrace 'x'
//     exiting  'E' (not printed for zombies)
//     vforked  'V'
//     system   'K' (and do not print 'L' too)
    if(pp->vm_lock)                   outbuf[end++] = 'L';
    if(pp->session == pp->tgid)       outbuf[end++] = 's'; // session leader
    if(pp->nlwp > 1)                  outbuf[end++] = 'l'; // multi-threaded
    if(pp->pgrp == pp->tpgid)         outbuf[end++] = '+'; // in foreground process group
    outbuf[end] = '\0';
    return end;
}

/* This minimal state display is Unix98 compliant, like SCO and SunOS 5 */
static int pr_s(char *restrict const outbuf, const proc_t *restrict const pp){
    outbuf[0] = pp->state;
    outbuf[1] = '\0';
    return 1;
}

static int pr_flag(char *restrict const outbuf, const proc_t *restrict const pp){
    /* Unix98 requires octal flags */
    /* this user-hostile and volatile junk gets 1 character */
    return snprintf(outbuf, COLWID, "%o", (unsigned)(pp->flags>>6U)&0x7U);
}

// plus these: euid,ruid,egroup,rgroup (elsewhere in this file)

/*********** non-standard ***********/

/*** BSD
sess	session pointer
(SCO has:Process session leader ID as a decimal value. (SESSION))
jobc	job control count
cpu	short-term cpu usage factor (for scheduling)
sl	sleep time (in seconds; 127 = infinity)
re	core residency time (in seconds; 127 = infinity)
pagein	pageins (same as majflt)
lim	soft memory limit
tsiz	text size (in Kbytes)
***/

static int pr_stackp(char *restrict const outbuf, const proc_t *restrict const pp){
    return snprintf(outbuf, COLWID, "%08x", (unsigned)(pp->start_stack));
}

static int pr_esp(char *restrict const outbuf, const proc_t *restrict const pp){
    return snprintf(outbuf, COLWID, "%08x", (unsigned)(pp->kstk_esp));
}

static int pr_eip(char *restrict const outbuf, const proc_t *restrict const pp){
    return snprintf(outbuf, COLWID, "%08x", (unsigned)(pp->kstk_eip));
}

/* This function helps print old-style time formats */
static int old_time_helper(char *dst, unsigned long long t, unsigned long long rel) {
  if(!t)            return snprintf(dst, COLWID, "    -");
  if(t == ~0ULL)    return snprintf(dst, COLWID, "   xx");
  if((long long)(t-=rel) < 0)  t=0ULL;
  if(t>9999ULL)     return snprintf(dst, COLWID, "%5Lu", t/100ULL);
  else              return snprintf(dst, COLWID, "%2u.%02u", (unsigned)t/100U, (unsigned)t%100U);
}

static int pr_bsdtime(char *restrict const outbuf, const proc_t *restrict const pp){
    unsigned long long t;
    unsigned u;
    t = pp->utime + pp->stime;
    if(include_dead_children) t += (pp->cutime + pp->cstime);
    u = t / Hertz;
    return snprintf(outbuf, COLWID, "%3u:%02u", u/60U, u%60U);
}

static int pr_bsdstart(char *restrict const outbuf, const proc_t *restrict const pp){
  time_t start;
  time_t seconds_ago;
  start = time_of_boot + pp->start_time / Hertz;
  seconds_ago = seconds_since_1970 - start;
  if(seconds_ago < 0) seconds_ago=0;
  if(seconds_ago > 3600*24)  strcpy(outbuf, ctime(&start)+4);
  else                       strcpy(outbuf, ctime(&start)+10);
  outbuf[6] = '\0';
  return 6;
}

static int pr_alarm(char *restrict const outbuf, const proc_t *restrict const pp){
    return old_time_helper(outbuf, pp->alarm, 0ULL);
}

/* HP-UX puts this in pages and uses "vsz" for kB */
static int pr_sz(char *restrict const outbuf, const proc_t *restrict const pp){
  return snprintf(outbuf, COLWID, "%lu", (pp->vm_size)/(page_size/1024));
}


/*
 * FIXME: trs,drs,tsiz,dsiz,m_trs,m_drs,vm_exe,vm_data,trss
 * I suspect some/all of those are broken. They seem to have been
 * inherited by Linux and AIX from early BSD systems. FreeBSD only
 * retains tsiz. The prefixed versions come from Debian.
 * Sun and Digital have none of this crap. The code here comes
 * from an old Linux ps, and might not be correct for ELF executables.
 *
 * AIX            TRS    size of resident-set (real memory) of text
 * AIX            TSIZ   size of text (shared-program) image
 * FreeBSD        tsiz   text size (in Kbytes)
 * 4.3BSD NET/2   trss   text resident set size (in Kbytes)
 * 4.3BSD NET/2   tsiz   text size (in Kbytes)
 */

/* kB data size. See drs, tsiz & trs. */
static int pr_dsiz(char *restrict const outbuf, const proc_t *restrict const pp){
    long dsiz = 0;
    if(pp->vsize) dsiz += (pp->vsize - pp->end_code + pp->start_code) >> 10;
    return snprintf(outbuf, COLWID, "%ld", dsiz);
}

/* kB text (code) size. See trs, dsiz & drs. */
static int pr_tsiz(char *restrict const outbuf, const proc_t *restrict const pp){
    long tsiz = 0;
    if(pp->vsize) tsiz += (pp->end_code - pp->start_code) >> 10;
    return snprintf(outbuf, COLWID, "%ld", tsiz);
}

/* kB _resident_ data size. See dsiz, tsiz & trs. */
static int pr_drs(char *restrict const outbuf, const proc_t *restrict const pp){
    long drs = 0;
    if(pp->vsize) drs += (pp->vsize - pp->end_code + pp->start_code) >> 10;
    return snprintf(outbuf, COLWID, "%ld", drs);
}

/* kB text _resident_ (code) size. See tsiz, dsiz & drs. */
static int pr_trs(char *restrict const outbuf, const proc_t *restrict const pp){
    long trs = 0;
    if(pp->vsize) trs += (pp->end_code - pp->start_code) >> 10;
    return snprintf(outbuf, COLWID, "%ld", trs);
}

/* approximation to: kB of address space that could end up in swap */
static int pr_swapable(char *restrict const outbuf, const proc_t *restrict const pp){
  return snprintf(outbuf, COLWID, "%ld", pp->vm_data + pp->vm_stack);
}

/* nasty old Debian thing */
static int pr_size(char *restrict const outbuf, const proc_t *restrict const pp){
  return snprintf(outbuf, COLWID, "%ld", pp->size);
}


static int pr_minflt(char *restrict const outbuf, const proc_t *restrict const pp){
    long flt = pp->min_flt;
    if(include_dead_children) flt += pp->cmin_flt;
    return snprintf(outbuf, COLWID, "%ld", flt);
}

static int pr_majflt(char *restrict const outbuf, const proc_t *restrict const pp){
    long flt = pp->maj_flt;
    if(include_dead_children) flt += pp->cmaj_flt;
    return snprintf(outbuf, COLWID, "%ld", flt);
}

static int pr_lim(char *restrict const outbuf, const proc_t *restrict const pp){
    if(pp->rss_rlim == RLIM_INFINITY){
      outbuf[0] = 'x';
      outbuf[1] = 'x';
      outbuf[2] = '\0';
      return 2;
    }
    return snprintf(outbuf, COLWID, "%5ld", pp->rss_rlim >> 10);
}

/* should print leading tilde ('~') if process is bound to the CPU */
static int pr_psr(char *restrict const outbuf, const proc_t *restrict const pp){
  return snprintf(outbuf, COLWID, "%d", pp->processor);
}

static int pr_rss(char *restrict const outbuf, const proc_t *restrict const pp){
  return snprintf(outbuf, COLWID, "%lu", pp->vm_rss);
}

/* pp->vm_rss * 1000 would overflow on 32-bit systems with 64 GB memory */
static int pr_pmem(char *restrict const outbuf, const proc_t *restrict const pp){
  unsigned long pmem = 0;
  pmem = pp->vm_rss * 1000ULL / kb_main_total;
  if (pmem > 999) pmem = 999;
  return snprintf(outbuf, COLWID, "%2u.%u", (unsigned)(pmem/10), (unsigned)(pmem%10));
}

static int pr_lstart(char *restrict const outbuf, const proc_t *restrict const pp){
  time_t t;
  t = time_of_boot + pp->start_time / Hertz;
  return snprintf(outbuf, COLWID, "%24.24s", ctime(&t));
}

/* Unix98 specifies a STIME header for a column that shows the start
 * time of the process, but does not specify a format or format specifier.
 * From the general Unix98 rules, we know there must not be any spaces.
 * Most systems violate that rule, though the Solaris documentation
 * claims to print the column without spaces. (NOT!)