lib_telldir.c 3.3 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990
  1. /****************************************************************************
  2. * libs/libc/dirent/fs_telldir.c
  3. *
  4. * Copyright (C) 2007-2008, 2011-2012 Gregory Nutt. All rights reserved.
  5. * Author: Gregory Nutt <gnutt@nuttx.org>
  6. *
  7. * Redistribution and use in source and binary forms, with or without
  8. * modification, are permitted provided that the following conditions
  9. * are met:
  10. *
  11. * 1. Redistributions of source code must retain the above copyright
  12. * notice, this list of conditions and the following disclaimer.
  13. * 2. Redistributions in binary form must reproduce the above copyright
  14. * notice, this list of conditions and the following disclaimer in
  15. * the documentation and/or other materials provided with the
  16. * distribution.
  17. * 3. Neither the name NuttX nor the names of its contributors may be
  18. * used to endorse or promote products derived from this software
  19. * without specific prior written permission.
  20. *
  21. * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22. * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23. * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  24. * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
  25. * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  26. * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
  27. * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
  28. * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  29. * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  30. * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
  31. * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  32. * POSSIBILITY OF SUCH DAMAGE.
  33. *
  34. ****************************************************************************/
  35. /****************************************************************************
  36. * Included Files
  37. ****************************************************************************/
  38. #include <nuttx/config.h>
  39. #include <sys/types.h>
  40. #include <dirent.h>
  41. #include <errno.h>
  42. #include <nuttx/fs/fs.h>
  43. #include <nuttx/fs/dirent.h>
  44. /****************************************************************************
  45. * Private Functions
  46. ****************************************************************************/
  47. /****************************************************************************
  48. * Public Functions
  49. ****************************************************************************/
  50. /****************************************************************************
  51. * Name: telldir
  52. *
  53. * Description:
  54. * The telldir() function returns the current location
  55. * associated with the directory stream dirp.
  56. *
  57. * Input Parameters:
  58. * dirp -- An instance of type DIR created by a previous
  59. * call to opendir();
  60. *
  61. * Returned Value:
  62. * On success, the telldir() function returns the current
  63. * location in the directory stream. On error, -1 is
  64. * returned, and errno is set appropriately.
  65. *
  66. * EBADF - Invalid directory stream descriptor dir
  67. *
  68. ****************************************************************************/
  69. off_t telldir(FAR DIR *dirp)
  70. {
  71. struct fs_dirent_s *idir = (struct fs_dirent_s *)dirp;
  72. if (!idir || !idir->fd_root)
  73. {
  74. set_errno(EBADF);
  75. return (off_t)-1;
  76. }
  77. /* Just return the current position */
  78. return idir->fd_position;
  79. }