iob_concat.c 2.8 KB

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  1. /****************************************************************************
  2. * mm/iob/iob_concat.c
  3. *
  4. * Copyright (C) 2014 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 <string.h>
  40. #include <nuttx/mm/iob.h>
  41. #include "iob.h"
  42. /****************************************************************************
  43. * Public Functions
  44. ****************************************************************************/
  45. /****************************************************************************
  46. * Name: iob_concat
  47. *
  48. * Description:
  49. * Concatenate iob_s chain iob2 to iob1.
  50. *
  51. ****************************************************************************/
  52. void iob_concat(FAR struct iob_s *iob1, FAR struct iob_s *iob2)
  53. {
  54. /* Combine the total packet size */
  55. iob1->io_pktlen += iob2->io_pktlen;
  56. iob2->io_pktlen = 0;
  57. /* Find the last buffer in the iob1 buffer chain */
  58. while (iob1->io_flink)
  59. {
  60. iob1 = iob1->io_flink;
  61. }
  62. /* Then connect iob2 buffer chain to the end of the iob1 chain */
  63. iob1->io_flink = iob2;
  64. }