execute_cmd.c

android-w.song.android.widget

    close_fd_bitmap (fds_to_close);

  do_piping (pipe_in, pipe_out);

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

  /* If this is a user subshell, set a flag if stdin was redirected.
     This is used later to decide whether to redirect fd 0 to
     /dev/null for async commands in the subshell.  This adds more
     sh compatibility, but I'm not sure it's the right thing to do. */
  if (user_subshell)
    {
      stdin_redir = stdin_redirects (command->redirects);
      restore_default_signal (0);
    }

  /* If this is an asynchronous command (command &), we want to
     redirect the standard input from /dev/null in the absence of
     any specific redirection involving stdin. */
  if (should_redir_stdin && stdin_redir == 0)
    async_redirect_stdin ();

  /* Do redirections, then dispose of them before recursive call. */
  if (command->redirects)
    {
      if (do_redirections (command->redirects, RX_ACTIVE) != 0)
	exit (invert ? EXECUTION_SUCCESS : EXECUTION_FAILURE);

      dispose_redirects (command->redirects);
      command->redirects = (REDIRECT *)NULL;
    }

  if (command->type == cm_subshell)
    tcom = command->value.Subshell->command;
  else if (user_coproc)
    tcom = command->value.Coproc->command;
  else
    tcom = command;

  if (command->flags & CMD_TIME_PIPELINE)
    tcom->flags |= CMD_TIME_PIPELINE;
  if (command->flags & CMD_TIME_POSIX)
    tcom->flags |= CMD_TIME_POSIX;
  
  /* Make sure the subshell inherits any CMD_IGNORE_RETURN flag. */
  if ((command->flags & CMD_IGNORE_RETURN) && tcom != command)
    tcom->flags |= CMD_IGNORE_RETURN;

  /* If this is a simple command, tell execute_disk_command that it
     might be able to get away without forking and simply exec.
     This means things like ( sleep 10 ) will only cause one fork.
     If we're timing the command or inverting its return value, however,
     we cannot do this optimization. */
  if ((user_subshell || user_coproc) && (tcom->type == cm_simple || tcom->type == cm_subshell) &&
      ((tcom->flags & CMD_TIME_PIPELINE) == 0) &&
      ((tcom->flags & CMD_INVERT_RETURN) == 0))
    {
      tcom->flags |= CMD_NO_FORK;
      if (tcom->type == cm_simple)
	tcom->value.Simple->flags |= CMD_NO_FORK;
    }

  invert = (tcom->flags & CMD_INVERT_RETURN) != 0;
  tcom->flags &= ~CMD_INVERT_RETURN;

  result = setjmp (top_level);

  /* If we're inside a function while executing this subshell, we
     need to handle a possible `return'. */
  function_value = 0;
  if (return_catch_flag)
    function_value = setjmp (return_catch);

  /* If we're going to exit the shell, we don't want to invert the return
     status. */
  if (result == EXITPROG)
    invert = 0, return_code = last_command_exit_value;
  else if (result)
    return_code = EXECUTION_FAILURE;
  else if (function_value)
    return_code = return_catch_value;
  else
    return_code = execute_command_internal (tcom, asynchronous, NO_PIPE, NO_PIPE, fds_to_close);

  /* If we are asked to, invert the return value. */
  if (invert)
    return_code = (return_code == EXECUTION_SUCCESS) ? EXECUTION_FAILURE
						     : EXECUTION_SUCCESS;

  /* If we were explicitly placed in a subshell with (), we need
     to do the `shell cleanup' things, such as running traps[0]. */
  if (user_subshell && signal_is_trapped (0))
    {
      last_command_exit_value = return_code;
      return_code = run_exit_trap ();
    }

  subshell_level--;
  return (return_code);
  /* NOTREACHED */
}

#if defined (COPROCESS_SUPPORT)
#define COPROC_MAX	16

typedef struct cpelement
  {
    struct cpelement *next;
    struct coproc *coproc;
  }
cpelement_t;
    
typedef struct cplist
  {
    struct cpelement *head;
    struct cpelement *tail;
    int ncoproc;
  }
cplist_t;

static struct cpelement *cpe_alloc __P((struct coproc *));
static void cpe_dispose __P((struct cpelement *));
static struct cpelement *cpl_add __P((struct coproc *));
static struct cpelement *cpl_delete __P((pid_t));
static void cpl_reap __P((void));
static void cpl_flush __P((void));
static struct cpelement *cpl_search __P((pid_t));
static struct cpelement *cpl_searchbyname __P((char *));
static void cpl_prune __P((void));

Coproc sh_coproc = { 0, NO_PID, -1, -1, 0, 0, 0, 0 };

cplist_t coproc_list = {0, 0, 0};

/* Functions to manage the list of coprocs */

static struct cpelement *
cpe_alloc (cp)
     Coproc *cp;
{
  struct cpelement *cpe;

  cpe = (struct cpelement *)xmalloc (sizeof (struct cpelement));
  cpe->coproc = cp;
  cpe->next = (struct cpelement *)0;
  return cpe;
}

static void
cpe_dispose (cpe)
      struct cpelement *cpe;
{
  free (cpe);
}

static struct cpelement *
cpl_add (cp)
     Coproc *cp;
{
  struct cpelement *cpe;

  cpe = cpe_alloc (cp);

  if (coproc_list.head == 0)
    {
      coproc_list.head = coproc_list.tail = cpe;
      coproc_list.ncoproc = 0;			/* just to make sure */
    }
  else
    {
      coproc_list.tail->next = cpe;
      coproc_list.tail = cpe;
    }
  coproc_list.ncoproc++;

  return cpe;
}

static struct cpelement *
cpl_delete (pid)
     pid_t pid;
{
  struct cpelement *prev, *p;

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

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

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

  /* Housekeeping in the border cases. */
  if (p == coproc_list.head)
    coproc_list.head = coproc_list.head->next;
  else if (p == coproc_list.tail)
    coproc_list.tail = prev;

  coproc_list.ncoproc--;
  if (coproc_list.ncoproc == 0)
    coproc_list.head = coproc_list.tail = 0;
  else if (coproc_list.ncoproc == 1)
    coproc_list.tail = coproc_list.head;		/* just to make sure */

  return (p);
}

static void
cpl_reap ()
{
  struct cpelement *prev, *p;

  for (prev = p = coproc_list.head; p; prev = p, p = p->next)
    if (p->coproc->c_flags & COPROC_DEAD)
      {
        prev->next = p->next;	/* remove from list */

	/* Housekeeping in the border cases. */
	if (p == coproc_list.head)
	  coproc_list.head = coproc_list.head->next;
	else if (p == coproc_list.tail)
	  coproc_list.tail = prev;

	coproc_list.ncoproc--;
	if (coproc_list.ncoproc == 0)
	  coproc_list.head = coproc_list.tail = 0;
	else if (coproc_list.ncoproc == 1)
	  coproc_list.tail = coproc_list.head;		/* just to make sure */

#if defined (DEBUG)
	itrace("cpl_reap: deleting %d", p->coproc->c_pid);
#endif

	coproc_dispose (p->coproc);
	cpe_dispose (p);
      }
}

/* Clear out the list of saved statuses */
static void
cpl_flush ()
{
  struct cpelement *cpe, *p;

  for (cpe = coproc_list.head; cpe; )
    {
      p = cpe;
      cpe = cpe->next;

      coproc_dispose (p->coproc);
      cpe_dispose (p);
    }

  coproc_list.head = coproc_list.tail = 0;
  coproc_list.ncoproc = 0;
}

/* Search for PID in the list of coprocs; return the cpelement struct if
   found.  If not found, return NULL. */
static struct cpelement *
cpl_search (pid)
     pid_t pid;
{
  struct cpelement *cp;

  for (cp = coproc_list.head ; cp; cp = cp->next)
    if (cp->coproc->c_pid == pid)
      return cp;
  return (struct cpelement *)NULL;
}

/* Search for the coproc named NAME in the list of coprocs; return the
   cpelement struct if found.  If not found, return NULL. */
static struct cpelement *
cpl_searchbyname (name)
     char *name;
{
  struct cpelement *cp;

  for (cp = coproc_list.head ; cp; cp = cp->next)
    if (STREQ (cp->coproc->c_name, name))
      return cp;
  return (struct cpelement *)NULL;
}

#if 0
static void
cpl_prune ()
{
  struct cpelement *cp;

  while (coproc_list.head && coproc_list.ncoproc > COPROC_MAX)
    {
      cp = coproc_list.head;
      coproc_list.head = coproc_list.head->next;
      coproc_dispose (cp->coproc);
      cpe_dispose (cp);
      coproc_list.ncoproc--;
    }
}
#endif

/* These currently use a single global "shell coproc" but are written in a
   way to not preclude additional coprocs later (using the list management
   package above). */

struct coproc *
getcoprocbypid (pid)
     pid_t pid;
{
  return (pid == sh_coproc.c_pid ? &sh_coproc : 0);
}

struct coproc *
getcoprocbyname (name)
     const char *name;
{
  return ((sh_coproc.c_name && STREQ (sh_coproc.c_name, name)) ? &sh_coproc : 0);
}

void
coproc_init (cp)
     struct coproc *cp;
{
  cp->c_name = 0;
  cp->c_pid = NO_PID;
  cp->c_rfd = cp->c_wfd = -1;
  cp->c_rsave = cp->c_wsave = -1;
  cp->c_flags = cp->c_status = 0;  
}

struct coproc *
coproc_alloc (name, pid)
     char *name;
     pid_t pid;
{
  struct coproc *cp;

  cp = &sh_coproc;		/* XXX */
  coproc_init (cp);

  cp->c_name = savestring (name);
  cp->c_pid = pid;

  return (cp);
}

void
coproc_dispose (cp)
     struct coproc *cp;
{
  if (cp == 0)
    return;

  coproc_unsetvars (cp);
  FREE (cp->c_name);
  coproc_close (cp);
  coproc_init (cp);
}

/* Placeholder for now. */
void
coproc_flush ()
{
  coproc_dispose (&sh_coproc);
}

void
coproc_close (cp)
     struct coproc *cp;
{
  if (cp->c_rfd >= 0)
    {
      close (cp->c_rfd);
      cp->c_rfd = -1;
    }
  if (cp->c_wfd >= 0)
    {
      close (cp->c_wfd);
      cp->c_wfd = -1;
    }
  cp->c_rsave = cp->c_wsave = -1;
}

void
coproc_closeall ()
{
  coproc_close (&sh_coproc);
}

void
coproc_reap ()
{
  struct coproc *cp;

  cp = &sh_coproc;
  if (cp && (cp->c_flags & COPROC_DEAD))
    coproc_dispose (cp);
}

void
coproc_rclose (cp, fd)
     struct coproc *cp;
     int fd;
{
  if (cp->c_rfd >= 0 && cp->c_rfd == fd)
    {
      close (cp->c_rfd);
      cp->c_rfd = -1;
    }
}

void
coproc_wclose (cp, fd)
     struct coproc *cp;
     int fd;
{
  if (cp->c_wfd >= 0 && cp->c_wfd == fd)
    {
      close (cp->c_wfd);
      cp->c_wfd = -1;
    }
}

void
coproc_checkfd (cp, fd)
     struct coproc *cp;
     int fd;
{
  int update;

  update = 0;
  if (cp->c_rfd >= 0 && cp->c_rfd == fd)
    update = cp->c_rfd = -1;
  if (cp->c_wfd >= 0 && cp->c_wfd == fd)
    update = cp->c_wfd = -1;
  if (update)
    coproc_setvars (cp);
}

void
coproc_fdchk (fd)
     int fd;
{
  coproc_checkfd (&sh_coproc, fd);
}

void
coproc_fdclose (cp, fd)
     struct coproc *cp;
     int fd;
{
  coproc_rclose (cp, fd);
  coproc_wclose (cp, fd);
  coproc_setvars (cp);
}

void
coproc_fdsave (cp)
     struct coproc *cp;
{
  cp->c_rsave = cp->c_rfd;
  cp->c_wsave = cp->c_wfd;
}

void