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reading in lines of text from file


gcc 4.5.1 c89

I am using the following code to read in a line of text from a configuration file. The configuration file is small at the moment, will grow with new fields to add. And I can pretty much design what the configuration file will look like myself. So I have done it in the following way:

config.cfg

# Configuration file to be loaded 

# protocol to use either ISDN, SIP, 
protocol: ISDN

# run application in the following mode, makecall or waitcall
mode: makecall

I have used the colon as a way to search for the type of configuration that will be needed. I am just wondering if there a better way to do this?

My code I have used is as follows:

static int load_config(FILE *fp)
{
    char line_read[LINE_SIZE] = {0};
    char *type = NULL;
    char field[LINE_SIZE] = {0};
    char *carriage_return = NULL;

    /* Read each line */
    while(fgets(line_read, LINE_SIZE, fp) != NULL) {
        if(line_read != NULL) {
            /* Ignore any hashs and blank lines */
            if((line_read[0] != '#') && (strlen(line_read) > 1)) {
                /* I don't like the carriage return, so remove it. */
                carriage_return = strrchr(line_read, '\n');
                if(carriage_return != NULL) {
                    /* carriage return found so relace with a null */
                    *carriage_return = '\0';
                }

                /* Parse line_read to extract the field name i.e. protocol, mode, etc */
                parse_string(field, line_read);
                if(field != NULL) {
                    type = strchr(line_read, ':');
                    type+=2; /* Point to the first character after the space */

                    if(strcmp("protocol", field) == 0) {
                        /* Check the protocol type */
                        printf("protocol [ %s ]\n", type);
                    }
                    else if (strcmp("mode", field) == 0) {
                        /* Check the mode type */
                        printf("mode [ %s ]\n", type);
                    }
                }
            }
        }
    }

    return TRUE;
}

/* Extract the field name for the read in line from the configuration file. */
static void parse_string(char *dest, const char *string)
{
    /* Copy string up to the colon to determine configuration type */
    while(*string != ':') {
        *dest++ = *string++;
    }
    /* Insert nul terminator */
    *dest = '\0';
}

Solution

  • easier should be:

    static int load_config(FILE *fp)
    {
      int r=0;
      char line[LINE_SIZE], field[LINE_SIZE], type[LINE_SIZE], dummy[LINE_SIZE];
    
      /* Read each line */
      while( fgets(line, LINE_SIZE, fp) )
      {
        if( strchr(line,'\n') ) *strchr(line,'\n')=0;
        if( 3==sscanf(line,"%[^: ]%[: ]%s,field,dummy,type) )
          ++r,printf("\n %s [ %s ]",field,type);
      }
      return r;
    }