simple.c 2.2 KB

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  1. #include <stdio.h>
  2. #include <pb_encode.h>
  3. #include <pb_decode.h>
  4. #include "simple.pb.h"
  5. int main()
  6. {
  7. /* This is the buffer where we will store our message. */
  8. uint8_t buffer[128];
  9. size_t message_length;
  10. bool status;
  11. /* Encode our message */
  12. {
  13. /* Allocate space on the stack to store the message data.
  14. *
  15. * Nanopb generates simple struct definitions for all the messages.
  16. * - check out the contents of simple.pb.h!
  17. * It is a good idea to always initialize your structures
  18. * so that you do not have garbage data from RAM in there.
  19. */
  20. SimpleMessage message = SimpleMessage_init_zero;
  21. /* Create a stream that will write to our buffer. */
  22. pb_ostream_t stream = pb_ostream_from_buffer(buffer, sizeof(buffer));
  23. /* Fill in the lucky number */
  24. message.lucky_number = 13;
  25. /* Now we are ready to encode the message! */
  26. status = pb_encode(&stream, SimpleMessage_fields, &message);
  27. message_length = stream.bytes_written;
  28. /* Then just check for any errors.. */
  29. if (!status)
  30. {
  31. printf("Encoding failed: %s\n", PB_GET_ERROR(&stream));
  32. return 1;
  33. }
  34. }
  35. /* Now we could transmit the message over network, store it in a file or
  36. * wrap it to a pigeon's leg.
  37. */
  38. /* But because we are lazy, we will just decode it immediately. */
  39. {
  40. /* Allocate space for the decoded message. */
  41. SimpleMessage message = SimpleMessage_init_zero;
  42. /* Create a stream that reads from the buffer. */
  43. pb_istream_t stream = pb_istream_from_buffer(buffer, message_length);
  44. /* Now we are ready to decode the message. */
  45. status = pb_decode(&stream, SimpleMessage_fields, &message);
  46. /* Check for errors... */
  47. if (!status)
  48. {
  49. printf("Decoding failed: %s\n", PB_GET_ERROR(&stream));
  50. return 1;
  51. }
  52. /* Print the data contained in the message. */
  53. printf("Your lucky number was %d!\n", (int)message.lucky_number);
  54. }
  55. return 0;
  56. }