Tengo una función que analizará algunos datos que entran. Mi problema es que después de usar strncpy obtengo algo de basura cuando intento imprimirlo. Intento usar malloc para hacer que la matriz char tenga el tamaño exacto.

Código:

void parse_data(char *unparsed_data)
{
char *temp_str;
char *pos;
char *pos2;
char *key;
char *data;
const char newline = '\n';

int timestamp = 0;

temp_str = (char*)malloc(strlen(unparsed_data));

g_print("\nThe original string is: \n%s\n",unparsed_data);


//Ignore the first two lines
pos = strchr(unparsed_data, newline);
strcpy(temp_str, pos+1);
pos = strchr(temp_str, newline);
strcpy(temp_str, pos+1);

//Split the line in two; The key name and the value
pos = strchr(temp_str, ':'); // ':' divides the name from the value
pos2 = strchr(temp_str, '\n'); //end of the line
key = (char*)malloc((size_t)(pos-temp_str)-1); //allocate enough memory
data = (char*)malloc((size_t)(pos2-pos)-1);

strncpy(key, temp_str, (size_t)(pos-temp_str));
strncpy(data, pos + 2, (size_t)(pos2-pos));

timestamp = atoi(data);

g_print("size of the variable \"key\" = %d or %d\n", (size_t)(pos-temp_str), strlen(key));
g_print("size of the variable \"data\" = %d or %d\n", (size_t)(pos2-pos), strlen(data));

g_print("The key name is %s\n",key);
g_print("The value is %s\n",data);
g_print("End of Parser\n");
  }

Salida:

The original string is: 
NEW_DATAa_PACKET
Local Data Set 16-byte Universal Key
Time Stamp (microsec): 1319639501097446
Frame Number: 0
Version: 3
Angle (deg): 10.228428

size of the variable "key" = 21 or 22
size of the variable "data" = 18 or 21
The key name is Time Stamp (microsec)
The value is 1319639501097446
F32
End of Parser

Ejecutarlo de nuevo:

  The original string is: 
  NEW_DATAa_PACKET
  Local Data Set 16-byte Universal Key
  Time Stamp (microsec): 1319639501097446
  Frame Number: 0
  Version: 3
  Angle (deg): 10.228428

  size of the variable "key" = 21 or 25
  size of the variable "data" = 18 or 18
  The key name is Time Stamp (microsec)ipe 
  The value is 1319639501097446
  F
  End of Parser