Re: ps display

I have applied this patch that Tom Lane and I worked on to fix the
display of WAIT status on setproctitle() displays.

Without the patch, on setproctitle() machines, the ps display was
truncated when waiting on a lock.

Here is an extended version of your patch that cleans things up some
more (uses StrNCpy, for example). I've checked the USE_PSTAT and
USE_CLOBBER_ARGV paths.

regards, tom lane

*** src/backend/utils/misc/ps_status.c.orig	Sat Feb 17 17:34:26 2001
--- src/backend/utils/misc/ps_status.c	Tue Mar 20 17:02:03 2001
***************
*** 44,50 ****
* PS_USE_PS_STRINGS
*     assign PS_STRINGS->ps_argvstr = "string"
*     (some BSD systems)
!  * PS_USE_CHANCE_ARGV
*     assign argv[0] = "string"
*     (some other BSD systems)
* PS_USE_CLOBBER_ARGV
--- 44,50 ----
* PS_USE_PS_STRINGS
*     assign PS_STRINGS->ps_argvstr = "string"
*     (some BSD systems)
!  * PS_USE_CHANGE_ARGV
*     assign argv[0] = "string"
*     (some other BSD systems)
* PS_USE_CLOBBER_ARGV
***************
*** 189,252 ****
void
set_ps_display(const char * value)
{
/* no ps display for stand-alone backend */
if (!IsUnderPostmaster)
return;

! #ifndef PS_USE_NONE
if (!ps_buffer)
return;
! # ifdef PS_USE_SETPROCTITLE
! setproctitle("%s%s", ps_buffer, value);

! # else /* not PS_USE_SETPROCTITLE */
! {
! size_t vallen = strlen(value);

! strncpy(ps_buffer + ps_buffer_fixed_size, value,
! ps_buffer_size - ps_buffer_fixed_size);

! if (ps_buffer_fixed_size + vallen >= ps_buffer_size)
! ps_buffer[ps_buffer_size - 1] = 0;
! else
! ps_buffer[ps_buffer_fixed_size + vallen] = 0;

! # ifdef PS_USE_PSTAT
{
union pstun pst;

pst.pst_command = ps_buffer;
pstat(PSTAT_SETCMD, pst, strlen(ps_buffer), 0, 0);
}
! # endif /* PS_USE_PSTAT */

! # ifdef PS_USE_PS_STRINGS
PS_STRINGS->ps_nargvstr = 1;
PS_STRINGS->ps_argvstr = ps_buffer;
! # endif /* PS_USE_PS_STRINGS */

! # ifdef PS_USE_CLOBBER_ARGV
{
char * cp;
/* pad unused memory */
! for(cp = ps_buffer + ps_buffer_fixed_size + vallen;
cp < ps_buffer + ps_buffer_size;
cp++)
*cp = PS_PADDING;
}
! # endif /* PS_USE_CLOBBER_ARGV */
! }
! # endif /* not USE_SETPROCTITLE */
#endif /* not PS_USE_NONE */
}

/*
* Returns what's currently in the ps display, in case someone needs
!  * it.
*/
const char *
get_ps_display(void)
{
return ps_buffer + ps_buffer_fixed_size;
}
--- 189,256 ----
void
set_ps_display(const char * value)
{
+ #ifndef PS_USE_NONE
/* no ps display for stand-alone backend */
if (!IsUnderPostmaster)
return;

! # ifdef PS_USE_CLOBBER_ARGV
! /* If ps_buffer is a pointer, it might still be null */
if (!ps_buffer)
return;
! # endif

! /* Update ps_buffer to contain both fixed part and value */
! StrNCpy(ps_buffer + ps_buffer_fixed_size, value,
! ps_buffer_size - ps_buffer_fixed_size);

! /* Transmit new setting to kernel, if necessary */

! # ifdef PS_USE_SETPROCTITLE
! setproctitle("%s", ps_buffer);
! # endif

! # ifdef PS_USE_PSTAT
{
union pstun pst;

pst.pst_command = ps_buffer;
pstat(PSTAT_SETCMD, pst, strlen(ps_buffer), 0, 0);
}
! # endif /* PS_USE_PSTAT */

! # ifdef PS_USE_PS_STRINGS
PS_STRINGS->ps_nargvstr = 1;
PS_STRINGS->ps_argvstr = ps_buffer;
! # endif /* PS_USE_PS_STRINGS */

! # ifdef PS_USE_CLOBBER_ARGV
{
char * cp;
/* pad unused memory */
! for(cp = ps_buffer + strlen(ps_buffer);
cp < ps_buffer + ps_buffer_size;
cp++)
*cp = PS_PADDING;
}
! # endif /* PS_USE_CLOBBER_ARGV */
!
#endif /* not PS_USE_NONE */
}

/*
* Returns what's currently in the ps display, in case someone needs
!  * it.  Note that only the variable part is returned.
*/
const char *
get_ps_display(void)
{
+ #ifdef PS_USE_CLOBBER_ARGV
+ 	/* If ps_buffer is a pointer, it might still be null */
+ 	if (!ps_buffer)
+ 		return "";
+ #endif
+ 
return ps_buffer + ps_buffer_fixed_size;
}

-- 
  Bruce Momjian                        |  http://candle.pha.pa.us
  pgman@candle.pha.pa.us               |  (610) 853-3000
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