procps/ps/select.c
Jim Warner 584028dbe5 ps: exploit those new <pids> task/threads capabilities
This commit represents the ps transition to the <pids>
'stacks' interface. While an effort to minimize impact
on existing code was made (as with a disguised proc_t)
the changes were still extensive. Along the way, a few
modifications beyond simply conversion were also made.

------------------------------------------------------
Here's a brief overview the design of this conversion:

. The need to satisfy relative enum requirements could
not easily have been made table driven since any entry
in the format_array might require several <pids> items
in support. So I decided to allow every print function
to contribute its own relative enums once the decision
as to exactly what will be printed had been finalized.

. A similar approach was taken for sorting, since it's
possible to have sort keys that will not be displayed.
Here, I relied on the existing print extensions above.

. In summary, just prior to printing ps walks thru two
lists one time (the format_list & sort_list) and calls
each print function. That function does not print, but
sets its required enum if necessary. Later, when those
same functions are called repeatedly for every printed
line, the only overhead will be an if test and branch.

------------------------------------------------------
Below is a summary of major changes beyond conversion:

. Sorts are now the responsibility of the library. And
therefore the total # of sortable fields substantially
increased without effort. Additionally, several quirky
fields remain as sortable, even though they can't ever
be printed(?). Surely that must make sense to someone.

[ while on this subject of sort, please do *not* try ]
[ to sort old ps on 'args'. or better yet, if you do ]
[ try that sort, see if you can determine his order, ]
[ without peeking at the source. that one hurts yet! ]

. All logic dealing with the old openproc flags and ps
struct members known as 'need' have been whacked since
that entire area was solely the new library's concern.

. Remaining malloc/calloc calls to stdlib were changed
to xmalloc/xcalloc from our own include/xalloc.h file.
None of the replaced calls ever checked return values.

[ be aware that 2 minor potential memory leaks exist ]
[ depending on command line arguments. no attempt is ]
[ made to free dynamically acquired format/sort node ]
[ structures upon return; a conscious design choice. ]

Signed-off-by: Jim Warner <james.warner@comcast.net>
2015-10-05 21:52:08 +11:00

152 lines
5.5 KiB
C

/*
* select.c - ps process selection
* Copyright 1998-2002 by Albert Cahalan
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "common.h"
//#define process_group_leader(p) (rSv(ID_PID, s_int, p) == rSv(ID_TGID, s_int, p))
//#define some_other_user(p) (rSv(ID_EUID, u_int, p) != cached_euid)
#define has_our_euid(p) (rSv(ID_EUID, u_int, p) == cached_euid)
#define on_our_tty(p) (rSv(TTY, s_int, p) == cached_tty)
#define running(p) (rSv(STATE, s_ch, p) == 'R' || rSv(STATE, s_ch, p) == 'D')
#define session_leader(p) (rSv(ID_SESSION, s_int, p) == rSv(ID_TGID, s_int, p))
#define without_a_tty(p) (!rSv(TTY, s_int, p))
static unsigned long select_bits = 0;
/***** prepare select_bits for use */
const char *select_bits_setup(void){
int switch_val = 0;
/* don't want a 'g' screwing up simple_select */
if(!simple_select && !prefer_bsd_defaults){
select_bits = 0xaa00; /* the STANDARD selection */
return NULL;
}
/* For every BSD but SunOS, the 'g' option is a NOP. (enabled by default) */
if( !(personality & PER_NO_DEFAULT_g) && !(simple_select&(SS_U_a|SS_U_d)) )
switch_val = simple_select|SS_B_g;
else
switch_val = simple_select;
switch(switch_val){
/* UNIX options */
case SS_U_a | SS_U_d: select_bits = 0x3f3f; break; /* 3333 or 3f3f */
case SS_U_a: select_bits = 0x0303; break; /* 0303 or 0f0f */
case SS_U_d: select_bits = 0x3333; break;
/* SunOS 4 only (others have 'g' enabled all the time) */
case 0: select_bits = 0x0202; break;
case SS_B_a: select_bits = 0x0303; break;
case SS_B_x : select_bits = 0x2222; break;
case SS_B_x | SS_B_a: select_bits = 0x3333; break;
/* General BSD options */
case SS_B_g : select_bits = 0x0a0a; break;
case SS_B_g | SS_B_a: select_bits = 0x0f0f; break;
case SS_B_g | SS_B_x : select_bits = 0xaaaa; break;
case SS_B_g | SS_B_x | SS_B_a: /* convert to -e instead of using 0xffff */
all_processes = 1;
simple_select = 0;
break;
default:
return _("process selection options conflict");
break;
}
return NULL;
}
/***** selected by simple option? */
static int table_accept(proc_t *buf){
unsigned proc_index;
proc_index = (has_our_euid(buf) <<0)
| (session_leader(buf) <<1)
| (without_a_tty(buf) <<2)
| (on_our_tty(buf) <<3);
return (select_bits & (1<<proc_index));
}
/***** selected by some kind of list? */
static int proc_was_listed(proc_t *buf){
selection_node *sn = selection_list;
int i;
if(!sn) return 0;
while(sn){
switch(sn->typecode){
default:
catastrophic_failure(__FILE__, __LINE__, _("please report this bug"));
#define return_if_match(foo,bar) \
i=sn->n; while(i--) \
if((unsigned)foo == (unsigned)(*(sn->u+i)).bar) \
return 1
break; case SEL_RUID: return_if_match(rSv(ID_RUID, u_int, buf),uid);
break; case SEL_EUID: return_if_match(rSv(ID_EUID, u_int, buf),uid);
break; case SEL_SUID: return_if_match(rSv(ID_SUID, u_int, buf),uid);
break; case SEL_FUID: return_if_match(rSv(ID_FUID, u_int, buf),uid);
break; case SEL_RGID: return_if_match(rSv(ID_RGID, u_int, buf),gid);
break; case SEL_EGID: return_if_match(rSv(ID_EGID, u_int, buf),gid);
break; case SEL_SGID: return_if_match(rSv(ID_SGID, u_int, buf),gid);
break; case SEL_FGID: return_if_match(rSv(ID_FGID, u_int, buf),gid);
break; case SEL_PGRP: return_if_match(rSv(ID_PGRP, s_int, buf),pid);
break; case SEL_PID : return_if_match(rSv(ID_TGID, s_int, buf),pid);
break; case SEL_PID_QUICK : return_if_match(rSv(ID_TGID, s_int, buf),pid);
break; case SEL_PPID: return_if_match(rSv(ID_PPID, s_int, buf),ppid);
break; case SEL_TTY : return_if_match(rSv(TTY, s_int, buf),tty);
break; case SEL_SESS: return_if_match(rSv(ID_SESSION, s_int, buf),pid);
break; case SEL_COMM: i=sn->n; while(i--)
if(!strncmp( rSv(CMD, str, buf), (*(sn->u+i)).cmd, 15 )) return 1;
#undef return_if_match
}
sn = sn->next;
}
return 0;
}
/***** This must satisfy Unix98 and as much BSD as possible */
int want_this_proc(proc_t *buf){
int accepted_proc = 1; /* assume success */
/* elsewhere, convert T to list, U sets x implicitly */
/* handle -e -A */
if(all_processes) goto finish;
/* use table for -a a d g x */
if((simple_select || !selection_list))
if(table_accept(buf)) goto finish;
/* search lists */
if(proc_was_listed(buf)) goto finish;
/* fail, fall through to loose ends */
accepted_proc = 0;
/* do r N */
finish:
if(running_only && !running(buf)) accepted_proc = 0;
if(negate_selection) return !accepted_proc;
return accepted_proc;
}