Question

您好我正在尝试使用protoc-c编译器实现proto3。这是.proto文件的包含。

syntax = "proto3";
message Submessage {
  int32 value=1;
}

message DMessage {
  Submessage a=1;
  Submessage b=2;
/*  Submessage c=3; */
}

序列化的C代码是：

#include <stdio.h>
#include <stdlib.h>
#include "example2.pb-c.h"

int main (int argc, const char * argv[])
{
  DMessage msg    = DMESSAGE__INIT;   // DMESSAGE
  Submessage sub1 = SUBMESSAGE__INIT; // SUBMESSAGE A
  Submessage sub2 = SUBMESSAGE__INIT; // SUBMESSAGE B
/*  Submessage sub3 = SUBMESSAGE__INIT; // SUBMESSAGE C */
  void *buf;
  unsigned len;

  printf("1\n");
  if (argc != 2 && argc != 3)
  { // Allow one or two integers
    fprintf(stderr,"usage: dmessage a [b]\n");
    return 1;
  }
  sub1.value = atoi (argv[1]);
  msg.a = &sub1;               // Point msg.a to sub1 data

  // NOTE: has_b is not required like amessage, therefore check for NULL on deserialze
  if (argc == 3) { sub2.value = atoi (argv[2]); msg.b = &sub2; } // Point msg.b to sub2 data

/*  sub3.value = atoi(argv[3]);
  msg.c = &sub3; */

  len = dmessage__get_packed_size (&msg); // This is the calculated packing length
  buf = malloc (len);                     // Allocate memory
  dmessage__pack (&msg, buf);             // Pack msg, including submessages

  fprintf(stderr,"Writing %d serialized bytes\n",len); // See the length of message
  fwrite (buf, len, 1, stdout);           // Write to stdout to allow direct command line piping

  free(buf); // Free the allocated serialized buffer
  return 0;
}

反序列化的C代码是：

#include <stdio.h>
#include "example2.pb-c.h"
#define MAX_MSG_SIZE 4096

int main (int argc, const char * argv[])
{
  DMessage *msg;         // DMessage using submessages
  Submessage *sub1,*sub2;// Submessages
  char c; int i=0;       // Data holders
  uint8_t buf[MAX_MSG_SIZE]; // Input data container for bytes

  while (fread(&c,1,1,stdin) != 0)
  {
    if (i >= MAX_MSG_SIZE)
    {
      fprintf(stderr,"message too long for allocated buffer\n");
      return 1;
    }
    buf[i++] = c;
  }

  msg = dmessage__unpack(NULL,i,buf); // Deserialize the serialized input
  if (msg == NULL)
  { // Something failed
    fprintf(stderr,"error unpacking incoming message\n");
    return 1;
  }
  sub1 = msg->a; sub2 = msg->b;
/*  sub3 = msg->c; */
  printf("Received: a=%d\n",sub1->value);
/*  printf("Received: b=%d\n",sub2->value);  */
  if (msg->b != NULL) printf(" b=%d",sub2->value);
  printf("\n");

  dmessage__free_unpacked(msg,NULL);

  return 0;
}

序列化代码工作正常，但问题是反序列化代码给出了“错误解包传入消息”。我尝试了各种组合，但它们没有用。有什么不对或我错过了什么？任何人都可以帮助吗？谢谢

使用proto3进行反序列化时出错

0 个答案: