jobs.c

android-w.song.android.widget

      for (i = js.j_jobslots; i; i--)
	if (jobs[i - 1])
	  break;
    }
  else
    {
#if 0
      /* This wraps around, but makes it inconvenient to extend the array */
      for (i = js.j_lastj+1; i != js.j_lastj; i++)
	{
	  if (i >= js.j_jobslots)
	    i = 0;
	  if (jobs[i] == 0)
	    break;
	}	
      if (i == js.j_lastj)
        i = js.j_jobslots;
#else
      /* This doesn't wrap around yet. */
      for (i = js.j_lastj ? js.j_lastj + 1 : js.j_lastj; i < js.j_jobslots; i++)
	if (jobs[i] == 0)
	  break;
#endif
    }

  /* Do we need more room? */

  /* First try compaction */
  if ((interactive_shell == 0 || subshell_environment) && i == js.j_jobslots && js.j_jobslots >= MAX_JOBS_IN_ARRAY)
    i = compact_jobs_list (0);

  /* If we can't compact, reallocate */
  if (i == js.j_jobslots)
    {
      js.j_jobslots += JOB_SLOTS;
      jobs = (JOB **)xrealloc (jobs, (js.j_jobslots * sizeof (JOB *)));

      for (j = i; j < js.j_jobslots; j++)
	jobs[j] = (JOB *)NULL;
    }

  /* Add the current pipeline to the job list. */
  if (the_pipeline)
    {
      register PROCESS *p;
      int any_running, any_stopped, n;

      newjob = (JOB *)xmalloc (sizeof (JOB));

      for (n = 1, p = the_pipeline; p->next != the_pipeline; n++, p = p->next)
	;
      p->next = (PROCESS *)NULL;
      newjob->pipe = REVERSE_LIST (the_pipeline, PROCESS *);
      for (p = newjob->pipe; p->next; p = p->next)
	;
      p->next = newjob->pipe;

      the_pipeline = (PROCESS *)NULL;
      newjob->pgrp = pipeline_pgrp;
      pipeline_pgrp = 0;

      newjob->flags = 0;

      /* Flag to see if in another pgrp. */
      if (job_control)
	newjob->flags |= J_JOBCONTROL;

      /* Set the state of this pipeline. */
      p = newjob->pipe;
      any_running = any_stopped = 0;
      do
	{
	  any_running |= PRUNNING (p);
	  any_stopped |= PSTOPPED (p);
	  p = p->next;
	}
      while (p != newjob->pipe);

      newjob->state = any_running ? JRUNNING : (any_stopped ? JSTOPPED : JDEAD);
      newjob->wd = job_working_directory ();
      newjob->deferred = deferred;

      newjob->j_cleanup = (sh_vptrfunc_t *)NULL;
      newjob->cleanarg = (PTR_T) NULL;

      jobs[i] = newjob;
      if (newjob->state == JDEAD && (newjob->flags & J_FOREGROUND))
	setjstatus (i);
      if (newjob->state == JDEAD)
	{
	  js.c_reaped += n;	/* wouldn't have been done since this was not part of a job */
	  js.j_ndead++;
	}
      js.c_injobs += n;

      js.j_lastj = i;
      js.j_njobs++;
    }
  else
    newjob = (JOB *)NULL;

  if (newjob)
    js.j_lastmade = newjob;

  if (async)
    {
      if (newjob)
	{
	  newjob->flags &= ~J_FOREGROUND;
	  newjob->flags |= J_ASYNC;
	  js.j_lastasync = newjob;
	}
      reset_current ();
    }
  else
    {
      if (newjob)
	{
	  newjob->flags |= J_FOREGROUND;
	  /*
	   *		!!!!! NOTE !!!!!  ([e-mail])
	   *
	   * The currently-accepted job control wisdom says to set the
	   * terminal's process group n+1 times in an n-step pipeline:
	   * once in the parent and once in each child.  This is where
	   * the parent gives it away.
	   *
	   * Don't give the terminal away if this shell is an asynchronous
	   * subshell.
	   *
	   */
	  if (job_control && newjob->pgrp && (subshell_environment&SUBSHELL_ASYNC) == 0)
	    maybe_give_terminal_to (shell_pgrp, newjob->pgrp, 0);
	}
    }

  stop_making_children ();
  UNBLOCK_CHILD (oset);
  return (newjob ? i : js.j_current);
}

/* Functions to manage the list of exited background pids whose status has
   been saved. */

static struct pidstat *
bgp_alloc (pid, status)
     pid_t pid;
     int status;
{
  struct pidstat *ps;

  ps = (struct pidstat *)xmalloc (sizeof (struct pidstat));
  ps->pid = pid;
  ps->status = status;
  ps->next = (struct pidstat *)0;
  return ps;
}

static struct pidstat *
bgp_add (pid, status)
     pid_t pid;
     int status;
{
  struct pidstat *ps;

  ps = bgp_alloc (pid, status);

  if (bgpids.list == 0)
    {
      bgpids.list = bgpids.end = ps;
      bgpids.npid = 0;			/* just to make sure */
    }
  else
    {
      bgpids.end->next = ps;
      bgpids.end = ps;
    }
  bgpids.npid++;

  if (bgpids.npid > js.c_childmax)
    bgp_prune ();

  return ps;
}

static int
bgp_delete (pid)
     pid_t pid;
{
  struct pidstat *prev, *p;

  for (prev = p = bgpids.list; p; prev = p, p = p->next)
    if (p->pid == pid)
      {
	prev->next = p->next;	/* remove from list */
	break;
      }

  if (p == 0)
    return 0;		/* not found */

#if defined (DEBUG)
  itrace("bgp_delete: deleting %d", pid);
#endif

  /* Housekeeping in the border cases. */
  if (p == bgpids.list)
    bgpids.list = bgpids.list->next;
  else if (p == bgpids.end)
    bgpids.end = prev;

  bgpids.npid--;
  if (bgpids.npid == 0)
    bgpids.list = bgpids.end = 0;
  else if (bgpids.npid == 1)
    bgpids.end = bgpids.list;		/* just to make sure */

  free (p);
  return 1;
}

/* Clear out the list of saved statuses */
static void
bgp_clear ()
{
  struct pidstat *ps, *p;

  for (ps = bgpids.list; ps; )
    {
      p = ps;
      ps = ps->next;
      free (p);
    }
  bgpids.list = bgpids.end = 0;
  bgpids.npid = 0;
}

/* Search for PID in the list of saved background pids; return its status if
   found.  If not found, return -1. */
static int
bgp_search (pid)
     pid_t pid;
{
  struct pidstat *ps;

  for (ps = bgpids.list ; ps; ps = ps->next)
    if (ps->pid == pid)
      return ps->status;
  return -1;
}

static void
bgp_prune ()
{
  struct pidstat *ps;

  while (bgpids.npid > js.c_childmax)
    {
      ps = bgpids.list;
      bgpids.list = bgpids.list->next;
      free (ps);
      bgpids.npid--;
    }
}

/* Reset the values of js.j_lastj and js.j_firstj after one or both have
   been deleted.  The caller should check whether js.j_njobs is 0 before
   calling this.  This wraps around, but the rest of the code does not.  At
   this point, it should not matter. */
static void
reset_job_indices ()
{
  int old;

  if (jobs[js.j_firstj] == 0)
    {
      old = js.j_firstj++;
      if (old >= js.j_jobslots)
	old = js.j_jobslots - 1;
      while (js.j_firstj != old)
	{
	  if (js.j_firstj >= js.j_jobslots)
	    js.j_firstj = 0;
	  if (jobs[js.j_firstj] || js.j_firstj == old)	/* needed if old == 0 */
	    break;
	  js.j_firstj++;
	}
      if (js.j_firstj == old)
        js.j_firstj = js.j_lastj = js.j_njobs = 0;
    }
  if (jobs[js.j_lastj] == 0)
    {
      old = js.j_lastj--;
      if (old < 0)
	old = 0;
      while (js.j_lastj != old)
	{
	  if (js.j_lastj < 0)
	    js.j_lastj = js.j_jobslots - 1;
	  if (jobs[js.j_lastj] || js.j_lastj == old)	/* needed if old == js.j_jobslots */
	    break;
	  js.j_lastj--;
	}
      if (js.j_lastj == old)
        js.j_firstj = js.j_lastj = js.j_njobs = 0;
    }
}
      
/* Delete all DEAD jobs that the user had received notification about. */
static void
cleanup_dead_jobs ()
{
  register int i;
  int os;

  if (js.j_jobslots == 0 || jobs_list_frozen)
    return;

  QUEUE_SIGCHLD(os);

  /* XXX could use js.j_firstj and js.j_lastj here */
  for (i = 0; i < js.j_jobslots; i++)
    {
#if defined (DEBUG)
      if (i < js.j_firstj && jobs[i])
	itrace("cleanup_dead_jobs: job %d non-null before js.j_firstj (%d)", i, js.j_firstj);
      if (i > js.j_lastj && jobs[i])
	itrace("cleanup_dead_jobs: job %d non-null after js.j_lastj (%d)", i, js.j_lastj);
#endif

      if (jobs[i] && DEADJOB (i) && IS_NOTIFIED (i))
	delete_job (i, 0);
    }

#if defined (COPROCESS_SUPPORT)
  coproc_reap ();
#endif

  UNQUEUE_SIGCHLD(os);
}

static int
processes_in_job (job)
     int job;
{
  int nproc;
  register PROCESS *p;

  nproc = 0;
  p = jobs[job]->pipe;
  do
    {
      p = p->next;
      nproc++;
    }
  while (p != jobs[job]->pipe);

  return nproc;
}

static void
delete_old_job (pid)
     pid_t pid;
{
  PROCESS *p;
  int job;

  job = find_job (pid, 0, &p);
  if (job != NO_JOB)
    {
#ifdef DEBUG
      itrace ("delete_old_job: found pid %d in job %d with state %d", pid, job, jobs[job]->state);
#endif
      if (JOBSTATE (job) == JDEAD)
	delete_job (job, DEL_NOBGPID);
      else
	{
	  internal_warning (_("forked pid %d appears in running job %d"), pid, job);
	  if (p)
	    p->pid = 0;
	}
    }
}

/* Reallocate and compress the jobs list.  This returns with a jobs array
   whose size is a multiple of JOB_SLOTS and can hold the current number of
   jobs.  Heuristics are used to minimize the number of new reallocs. */
static void
realloc_jobs_list ()
{
  sigset_t set, oset;
  int nsize, i, j, ncur, nprev;
  JOB **nlist;

  ncur = nprev = NO_JOB;
  nsize = ((js.j_njobs + JOB_SLOTS - 1) / JOB_SLOTS);
  nsize *= JOB_SLOTS;
  i = js.j_njobs % JOB_SLOTS;
  if (i == 0 || i > (JOB_SLOTS >> 1))
    nsize += JOB_SLOTS;

  BLOCK_CHILD (set, oset);
  nlist = (js.j_jobslots == nsize) ? jobs : (JOB **) xmalloc (nsize * sizeof (JOB *));

  js.c_reaped = js.j_ndead = 0;
  for (i = j = 0; i < js.j_jobslots; i++)
    if (jobs[i])
      {
	if (i == js.j_current)
	  ncur = j;
	if (i == js.j_previous)
	  nprev = j;
	nlist[j++] = jobs[i];
	if (jobs[i]->state == JDEAD)
	  {
	    js.j_ndead++;
	    js.c_reaped += processes_in_job (i);
	  }
      }

#if defined (DEBUG)
  itrace ("realloc_jobs_list: resize jobs list from %d to %d", js.j_jobslots, nsize);
  itrace ("realloc_jobs_list: j_lastj changed from %d to %d", js.j_lastj, (j > 0) ? j - 1 : 0);
  itrace ("realloc_jobs_list: j_njobs changed from %d to %d", js.j_njobs, j);
  itrace ("realloc_jobs_list: js.j_ndead %d js.c_reaped %d", js.j_ndead, js.c_reaped);
#endif

  js.j_firstj = 0;
  js.j_lastj = (j > 0) ? j - 1 : 0;
  js.j_njobs = j;
  js.j_jobslots = nsize;

  /* Zero out remaining slots in new jobs list */
  for ( ; j < nsize; j++)
    nlist[j] = (JOB *)NULL;

  if (jobs != nlist)
    {
      free (jobs);
      jobs = nlist;
    }

  if (ncur != NO_JOB)
    js.j_current = ncur;
  if (nprev != NO_JOB)
    js.j_previous = nprev;

  /* Need to reset these */
  if (js.j_current == NO_JOB || js.j_previous == NO_JOB || js.j_current > js.j_lastj || js.j_previous > js.j_lastj)
    reset_current ();

#ifdef DEBUG
  itrace ("realloc_jobs_list: reset js.j_current (%d) and js.j_previous (%d)", js.j_current, js.j_previous);
#endif

  UNBLOCK_CHILD (oset);
}

/* Compact the jobs list by removing dead jobs.  Assumed that we have filled
   the jobs array to some predefined maximum.  Called when the shell is not
   the foreground process (subshell_environment != 0).  Returns the first
   available slot in the compacted list.  If that value is js.j_jobslots, then
   the list needs to be reallocated.  The jobs array may be in new memory if
   this returns > 0 and < js.j_jobslots.  FLAGS is reserved for future use. */
static int
compact_jobs_list (flags)
     int flags;
{
  if (js.j_jobslots == 0 || jobs_list_frozen)
    return js.j_jobslots;

  reap_dead_jobs ();
  realloc_jobs_list ();

#ifdef DEBUG
  itrace("compact_jobs_list: returning %d", (js.j_lastj || jobs[js.j_lastj]) ? js.j_lastj + 1 : 0);
#endif

  return ((js.j_lastj || jobs[js.j_lastj]) ? js.j_lastj + 1 : 0);
}

/* Delete the job at INDEX from the job list.  Must be called
   with SIGCHLD blocked. */
void
delete_job (job_index, dflags)
     int job_index, dflags;
{
  register JOB *temp;
  PROCESS *proc;
  int ndel;

  if (js.j_jobslots == 0 || jobs_list_frozen)
    return;

  if ((dflags & DEL_WARNSTOPPED) && subshell_environment == 0 && STOPPED (job_index))
    internal_warning (_("deleting stopped job %d with process group %ld"), job_index+1, (long)jobs[job_index]->pgrp);
  temp = jobs[job_index];
  if (temp == 0)
    return;

  if ((dflags & DEL_NOBGPID) == 0)
    {
      proc = find_last_proc (job_index, 0);
      /* Could do this just for J_ASYNC jobs, but we save all. */
      if (proc)
	bgp_add (proc->pid, process_exit_status (proc->status));
    }

  jobs[job_index] = (JOB *)NULL;
  if (temp == js.j_lastmade)
    js.j_lastmade = 0;