input.c

android-w.song.android.widget

  if (fd1 == fd2)
    return 0;

  m = max (fd1, fd2);
  ALLOCATE_BUFFERS (m);

  /* If FD2 is the file descriptor bash is currently using for shell input,
     we need to do some extra work to make sure that the buffered stream
     actually exists (it might not if fd1 was not active, and the copy
     didn't actually do anything). */
  is_bash_input = (bash_input.type == st_bstream) &&
		  (bash_input.location.buffered_fd == fd2);

  if (buffers[fd2])
    {
      /* If the two objects share the same b_buffer, don't free it. */
      if (buffers[fd1] && buffers[fd1]->b_buffer && buffers[fd1]->b_buffer == buffers[fd2]->b_buffer)
	buffers[fd2] = (BUFFERED_STREAM *)NULL;
      else
	free_buffered_stream (buffers[fd2]);
    }
  buffers[fd2] = copy_buffered_stream (buffers[fd1]);
  if (buffers[fd2])
    buffers[fd2]->b_fd = fd2;

  if (is_bash_input)
    {
      if (!buffers[fd2])
	fd_to_buffered_stream (fd2);
      buffers[fd2]->b_flag |= B_WASBASHINPUT;
    }

  return (fd2);
}

/* Return 1 if a seek on FD will succeed. */
#define fd_is_seekable(fd) (lseek ((fd), 0L, SEEK_CUR) >= 0)

/* Take FD, a file descriptor, and create and return a buffered stream
   corresponding to it.  If something is wrong and the file descriptor
   is invalid, return a NULL stream. */
BUFFERED_STREAM *
fd_to_buffered_stream (fd)
     int fd;
{
  char *buffer;
  size_t size;
  struct stat sb;

  if (fstat (fd, &sb) < 0)
    {
      close (fd);
      return ((BUFFERED_STREAM *)NULL);
    }

  size = (fd_is_seekable (fd)) ? min (sb.st_size, MAX_INPUT_BUFFER_SIZE) : 1;
  if (size == 0)
    size = 1;
  buffer = (char *)xmalloc (size);

  return (make_buffered_stream (fd, buffer, size));
}

/* Return a buffered stream corresponding to FILE, a file name. */
BUFFERED_STREAM *
open_buffered_stream (file)
     char *file;
{
  int fd;

  fd = open (file, O_RDONLY);
  return ((fd >= 0) ? fd_to_buffered_stream (fd) : (BUFFERED_STREAM *)NULL);
}

/* Deallocate a buffered stream and free up its resources.  Make sure we
   zero out the slot in BUFFERS that points to BP. */
void
free_buffered_stream (bp)
     BUFFERED_STREAM *bp;
{
  int n;

  if (!bp)
    return;

  n = bp->b_fd;
  if (bp->b_buffer)
    free (bp->b_buffer);
  free (bp);
  buffers[n] = (BUFFERED_STREAM *)NULL;
}

/* Close the file descriptor associated with BP, a buffered stream, and free
   up the stream.  Return the status of closing BP's file descriptor. */
int
close_buffered_stream (bp)
     BUFFERED_STREAM *bp;
{
  int fd;

  if (!bp)
    return (0);
  fd = bp->b_fd;
  free_buffered_stream (bp);
  return (close (fd));
}

/* Deallocate the buffered stream associated with file descriptor FD, and
   close FD.  Return the status of the close on FD. */
int
close_buffered_fd (fd)
     int fd;
{
  if (fd < 0)
    {
      errno = EBADF;
      return -1;
    }
  if (fd >= nbuffers || !buffers || !buffers[fd])
    return (close (fd));
  return (close_buffered_stream (buffers[fd]));
}

/* Make the BUFFERED_STREAM associcated with buffers[FD] be BP, and return
   the old BUFFERED_STREAM. */
BUFFERED_STREAM *
set_buffered_stream (fd, bp)
     int fd;
     BUFFERED_STREAM *bp;
{
  BUFFERED_STREAM *ret;

  ret = buffers[fd];
  buffers[fd] = bp;
  return ret;
}

/* Read a buffer full of characters from BP, a buffered stream. */
static int
b_fill_buffer (bp)
     BUFFERED_STREAM *bp;
{
  ssize_t nr;
  off_t o;

  CHECK_TERMSIG;
  /* In an environment where text and binary files are treated differently,
     compensate for lseek() on text files returning an offset different from
     the count of characters read() returns.  Text-mode streams have to be
     treated as unbuffered. */
  if ((bp->b_flag & (B_TEXT | B_UNBUFF)) == B_TEXT)
    {
      o = lseek (bp->b_fd, 0, SEEK_CUR);
      nr = zread (bp->b_fd, bp->b_buffer, bp->b_size);
      if (nr > 0 && nr < lseek (bp->b_fd, 0, SEEK_CUR) - o)
	{
	  lseek (bp->b_fd, o, SEEK_SET);
	  bp->b_flag |= B_UNBUFF;
	  bp->b_size = 1;
	  nr = zread (bp->b_fd, bp->b_buffer, bp->b_size);
	}
    }
  else
    nr = zread (bp->b_fd, bp->b_buffer, bp->b_size);
  if (nr <= 0)
    {
      bp->b_used = 0;
      bp->b_buffer[0] = 0;
      if (nr == 0)
	bp->b_flag |= B_EOF;
      else
	bp->b_flag |= B_ERROR;
      return (EOF);
    }

  bp->b_used = nr;
  bp->b_inputp = 0;
  return (bp->b_buffer[bp->b_inputp++] & 0xFF);
}

/* Get a character from buffered stream BP. */
#define bufstream_getc(bp) \
  (bp->b_inputp == bp->b_used || !bp->b_used) \
  		? b_fill_buffer (bp) \
		: bp->b_buffer[bp->b_inputp++] & 0xFF

/* Push C back onto buffered stream BP. */
static int
bufstream_ungetc(c, bp)
     int c;
     BUFFERED_STREAM *bp;
{
  if (c == EOF || bp->b_inputp == 0)
    return (EOF);

  bp->b_buffer[--bp->b_inputp] = c;
  return (c);
}

/* Seek backwards on file BFD to synchronize what we've read so far
   with the underlying file pointer. */
int
sync_buffered_stream (bfd)
     int bfd;
{
  BUFFERED_STREAM *bp;
  off_t chars_left;

  if (buffers == 0 || (bp = buffers[bfd]) == 0)
    return (-1);

  chars_left = bp->b_used - bp->b_inputp;
  if (chars_left)
    lseek (bp->b_fd, -chars_left, SEEK_CUR);
  bp->b_used = bp->b_inputp = 0;
  return (0);
}

int
buffered_getchar ()
{
  CHECK_TERMSIG;

#if !defined (DJGPP)
  return (bufstream_getc (buffers[bash_input.location.buffered_fd]));
#else
  /* On DJGPP, ignore \r. */
  int ch;
  while ((ch = bufstream_getc (buffers[bash_input.location.buffered_fd])) == '\r')
    ;
  return ch;
#endif
}

int
buffered_ungetchar (c)
     int c;
{
  return (bufstream_ungetc (c, buffers[bash_input.location.buffered_fd]));
}

/* Make input come from file descriptor BFD through a buffered stream. */
void
with_input_from_buffered_stream (bfd, name)
     int bfd;
     char *name;
{
  INPUT_STREAM location;
  BUFFERED_STREAM *bp;

  location.buffered_fd = bfd;
  /* Make sure the buffered stream exists. */
  bp = fd_to_buffered_stream (bfd);
  init_yy_io (bp == 0 ? return_EOF : buffered_getchar,
	      buffered_ungetchar, st_bstream, name, location);
}

#if defined (TEST)
void *
xmalloc(s)
int s;
{
	return (malloc (s));
}

void *
xrealloc(s, size)
char	*s;
int	size;
{
	if (!s)
		return(malloc (size));
	else
		return(realloc (s, size));
}

void
init_yy_io ()
{
}

process(bp)
BUFFERED_STREAM *bp;
{
	int c;

	while ((c = bufstream_getc(bp)) != EOF)
		putchar(c);
}

BASH_INPUT bash_input;

struct stat dsb;		/* can be used from gdb */

/* imitate /bin/cat */
main(argc, argv)
int	argc;
char	**argv;
{
	register int i;
	BUFFERED_STREAM *bp;

	if (argc == 1) {
		bp = fd_to_buffered_stream (0);
		process(bp);
		exit(0);
	}
	for (i = 1; i < argc; i++) {
		if (argv[i][0] == '-' && argv[i][1] == '\0') {
			bp = fd_to_buffered_stream (0);
			if (!bp)
				continue;
			process(bp);
			free_buffered_stream (bp);
		} else {
			bp = open_buffered_stream (argv[i]);
			if (!bp)
				continue;
			process(bp);
			close_buffered_stream (bp);
		}
	}
	exit(0);
}
#endif /* TEST */
#endif /* BUFFERED_INPUT */