CODEWITHSUNDEEP
c
schmitsz
schmitsz

Reputation: 175

Find longest comment line in a file in C

So I have this function to find the longest line in a file:

int LongestLine(FILE *filename) {

  char buf[MAX_LINE_LENGTH] = {0};

  char line_val[MAX_LINE_LENGTH] = {0};
  int line_len = -1;
  int line_num = -1;
  int cur_line = 1;

  filename = fopen(filename, "r");

  while(fgets(buf, MAX_LINE_LENGTH, filename) != NULL) {
    int len_tmp = strlen(buf) - 1;

    if(buf[len_tmp] == '\n')
      buf[len_tmp] = '\0';

    if(line_len < len_tmp) {
      strncpy(line_val, buf, len_tmp + 1);
      line_len = len_tmp;
      line_num = cur_line;
    }

    cur_line++;
  }

  return line_num;
}

and I was thinking of combining it with this one:

bool startsWith(const char *pre, const char *str)
{
    size_t lenpre = strlen(pre),
           lenstr = strlen(str);
    return lenstr < lenpre ? false : strncmp(pre, str, lenpre) == 0;
}

But.. however, the LongestLine() function returns an integer. So how can I use both functions so that I may find the longest line starting with let's say //?

Upvotes: 0

Views: 143

Answers (1)

Scott Hunter
Scott Hunter

Reputation: 49813

Add a call to startsWith (to see if it is a comment) in your if statement to decide if a line is the new longest:

if( startsWith("//",buf) && (line_len < len_tmp) ) {

Upvotes: 1

Related Questions