#include <windows.h>
#include <stdio.h>
#include <stdlib.h>


void usage(void);


void set_up_serial_port(HANDLE h, long baud);


void get_file_from_serial_port(HANDLE h, char *file_name, unsigned long file_length);

int main(int argc, char **argv)
{
HANDLE serial_port;    
long baud_rate = 9600;   
char port_name[] = "COM1:";  
unsigned long file_size;  
unsigned long bytes_received; 
unsigned long file_name_size; 
char file_name[256];   


if (argc == 3)
{
 
  if (argv[1][1] != 'b' || sscanf(argv[2], "%ld", &baud_rate) != 1)
  {
   usage();
   exit(0);
  }
}
else if (argc != 1)
{
  usage();
  exit(0);
}


serial_port = CreateFile(port_name, GENERIC_READ | GENERIC_WRITE, 0, 0, OPEN_EXISTING, 0, 0);


if (serial_port == INVALID_HANDLE_VALUE)
{
  fprintf(stderr, "Error opening portn");
  CloseHandle(serial_port);
  exit(0);
}


set_up_serial_port(serial_port, baud_rate);


ReadFile(serial_port, (void *)&file_name_size, sizeof(unsigned long), &bytes_received, NULL);
if (bytes_received != sizeof(unsigned long))
{
  fprintf(stderr, "Error getting file name size.n");
  CloseHandle(serial_port);
  exit(0);
}


ReadFile(serial_port, (void *)file_name, file_name_size, &bytes_received, NULL);
if (bytes_received != file_name_size)
{
  fprintf(stderr, "Error retrieving file name.n");
  CloseHandle(serial_port);
  exit(0);
}


file_name[bytes_received] = ' ';


ReadFile(serial_port, (void *)&file_size, sizeof(unsigned long), &bytes_received, NULL);
if (bytes_received != sizeof(unsigned long))
{
  fprintf(stderr, "Error getting file size.n");
  CloseHandle(serial_port);
  exit(0);
}


get_file_from_serial_port(serial_port, file_name, file_size);


printf("n%lu bytes successfully received and saved as %sn", file_size, file_name);


CloseHandle(serial_port);

return 0;
}

void usage(void)
{
fprintf(stderr, "Usage:n");
fprintf(stderr, "tserrecv [-b baud rate]n");
fprintf(stderr, "tDefault baud rate is 9600n");
fprintf(stderr, "tSupported baud rates: 1200, 2400, 4800, 9600, 14400, 19200n");
return;
}

void set_up_serial_port(HANDLE h, long baud)
{
DCB properties;  


GetCommState(h, &properties);


switch(baud)
{
case 1200:
  properties.BaudRate = CBR_1200;
  break;
case 2400:
  properties.BaudRate = CBR_2400;
  break;
case 4800:
  properties.BaudRate = CBR_4800;
  break;
case 9600:
  properties.BaudRate = CBR_9600;
  break;
case 14400:
  properties.BaudRate = CBR_14400;
  break;
case 19200:
  properties.BaudRate = CBR_19200;
  break;
case 38400:
  properties.BaudRate = CBR_38400;
  break;
default:
  fprintf(stderr, "Invalid baud rate: %ldn", baud);
  usage();
  exit(0);
  break;
}


properties.Parity = NOPARITY;
properties.ByteSize = 8;
properties.StopBits = ONESTOPBIT;

SetCommState(h, &properties);

return;
}

void get_file_from_serial_port(HANDLE h, char *file_name, unsigned long file_length)
{
FILE *data_file;     
unsigned long bytes_left = file_length;
unsigned long bytes_received_total = 0;
unsigned long bytes_to_receive;  
unsigned long bytes_received;  
char buffer[200];     


data_file = fopen(file_name, "wb");


if (data_file == NULL)
{
  fprintf(stderr, "Could not create file %sn", file_name);
  CloseHandle(h);
  exit(0);
}

while (1)
{
 
  if (bytes_left == 0)
  {
   break;
  }
  else if (bytes_left < 200)
  {
   bytes_to_receive = bytes_left;
  }
  else
  {
   bytes_to_receive = 200;
  }

 
  ReadFile(h, (void *)buffer, bytes_to_receive, &bytes_received, NULL);
  if (bytes_received != bytes_to_receive)
  {
   fprintf(stderr, "Error reading file.n");
   CloseHandle(h);
   exit(0);
  }

 
  fwrite((void *)buffer, 1, bytes_received, data_file);
 
 
  bytes_left -= bytes_received;

 
  bytes_received_total += bytes_received;

 
  printf("r%5lu bytes received.", bytes_received_total);
}

fclose(data_file);

return;
}