usr/src/lib/libcmd/common/pids.c

   1 /***********************************************************************
   2 *                                                                      *
   3 *               This software is part of the ast package               *
   4 *          Copyright (c) 1992-2010 AT&T Intellectual Property          *
   5 *                      and is licensed under the                       *
   6 *                  Common Public License, Version 1.0                  *
   7 *                    by AT&T Intellectual Property                     *
   8 *                                                                      *
   9 *                A copy of the License is available at                 *
  10 *            http://www.opensource.org/licenses/cpl1.0.txt             *
  11 *         (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9)         *
  12 *                                                                      *
  13 *              Information and Software Systems Research               *
  14 *                            AT&T Research                             *
  15 *                           Florham Park NJ                            *
  16 *                                                                      *
  17 *                 Glenn Fowler <gsf@research.att.com>                  *
  18 *                  David Korn <dgk@research.att.com>                   *
  19 *                                                                      *
  20 ***********************************************************************/
  21 #pragma prototyped
  22
  23 #define FORMAT          "PID=%(pid)d PPID=%(ppid)d PGID=%(pgid)d TID=%(tid)d SID=%(sid)d"
  24
  25 static const char usage[] =
  26 "[-?\n@(#)$Id: pids (AT&T Research) 2008-04-01 $\n]"
  27 USAGE_LICENSE
  28 "[+NAME?pids - list calling shell process ids]"
  29 "[+DESCRIPTION?When invoked as a shell builtin, \bpids\b lists one or "
  30     "more of the calling process ids determined by \bgetpid\b(2), "
  31     "\bgetppid\b(2), \bgetpgrp\b(2), \btcgetpgrp\b(2) and \bgetsid\b(2). "
  32     "Unknown or invalid ids have the value \b-1\b.]"
  33 "[f:format?List the ids specified by \aformat\a. \aformat\a follows "
  34     "\bprintf\b(3) conventions, except that \bsfio\b(3) inline ids are used "
  35     "instead of arguments: "
  36     "%[-+]][\awidth\a[.\aprecis\a[.\abase\a]]]]]](\aid\a)\achar\a. The "
  37     "supported \aid\as are:]:[format:=" FORMAT "]"
  38     "{"
  39         "[+pid?The process id.]"
  40         "[+pgid?The process group id.]"
  41         "[+ppid?The parent process id.]"
  42         "[+tid|tty?The controlling terminal id.]"
  43         "[+sid?The session id.]"
  44     "}"
  45 "[+SEE ALSO?\bgetpid\b(2), \bgetppid\b(2), \bgetpgrp\b(2), "
  46     "\btcgetpgrp\b(2), \bgetsid\b(2)]"
  47 ;
  48
  49 #include <cmd.h>
  50 #include <ast_tty.h>
  51 #include <sfdisc.h>
  52
  53 /*
  54  * sfkeyprintf() lookup
  55  * handle==0 for heading
  56  */
  57
  58 static int
  59 key(void* handle, Sffmt_t* fp, const char* arg, char** ps, Sflong_t* pn)
  60 {
  61         register char*  s;
  62         int             fd;
  63         long            tid;
  64
  65         if (!(s = fp->t_str) || streq(s, "pid"))
  66                 *pn = getpid();
  67         else if (streq(s, "pgid"))
  68                 *pn = getpgid(0);
  69         else if (streq(s, "ppid"))
  70                 *pn = getppid();
  71         else if (streq(s, "tid") || streq(s, "tty"))
  72         {
  73                 for (fd = 0; fd < 3; fd++)
  74                         if ((tid = tcgetpgrp(fd)) >= 0)
  75                                 break;
  76                 *pn = tid;
  77         }
  78         else if (streq(s, "sid"))
  79                 *pn = getsid(0);
  80         else if (streq(s, "format"))
  81                 *ps = (char*)handle;
  82         else
  83         {
  84                 error(2, "%s: unknown format identifier", s);
  85                 return 0;
  86         }
  87         return 1;
  88 }
  89
  90 int
  91 b_pids(int argc, char** argv, void* context)
  92 {
  93         char*                   format = 0;
  94
  95         cmdinit(argc, argv, context, ERROR_CATALOG, 0);
  96         for (;;)
  97         {
  98                 switch (optget(argv, usage))
  99                 {
 100                 case 'f':
 101                         format = opt_info.arg;
 102                         continue;
 103                 case '?':
 104                         error(ERROR_USAGE|4, "%s", opt_info.arg);
 105                         continue;
 106                 case ':':
 107                         error(2, "%s", opt_info.arg);
 108                         continue;
 109                 }
 110                 break;
 111         }
 112         argv += opt_info.index;
 113         if (error_info.errors || *argv)
 114                 error(ERROR_USAGE|4, "%s", optusage(NiL));
 115         if (!format)
 116                 format = FORMAT;
 117         sfkeyprintf(sfstdout, format, format, key, NiL);
 118         sfprintf(sfstdout, "\n");
 119         return 0;
 120 }