Re: ps display - Mailing list pgsql-patches

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;
>   }
>


--
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