number of substring occurences

Hello,
I wrote function that is supposed to count substring occurences in a line of text. here's my solution:

Code:

---

size_t count_substring ( const char* source, const char* substr )
{
        size_t count = 0;
        char* p;
       
        for ( p = source; *p; p++ )
        {
                int i = 0;
                char* t = p;
               
                while ( substr[i] != '\0' )
                {
                        if ( *t != substr[i] )
                        {
                                break;
                        }
                        t++;
                        i++;
                }
                if ( substr[i] == '\0' )
                {
                        count++;
                        p = --t;
                }
        }
        return count;
}

---

And here is test code

Code:

---

int main ( void )
{
        char line[BUFSIZ];
        printf ( "Enter line of text: ");
        fgets ( line, sizeof line, stdin );
        printf ( "\nTotal number is %u", count_substring ( line, "sam" ) );
        return 0;
}

---

I wonder if this could be done more elegant. I'd like to hear your advices...
Thanks

I say take advantage of the standard library functions when possible:

Code:

---

unsigned int substr_count(char *str, char *substr)
{
  unsigned int count = 0;
  size_t sublen = strlen(substr);

  while((str = strstr(str, substr)))
  {
    str += sublen;
    count++;
  }

  return count;
}

---

Very elegant, great solution, thanks.
I'm just wondering, why did you change return type from size_t to unsigned int?

- Micko

Well they are almost the same thing. IIRC size_t is just an unsigned long.

Quote:

---

why did you change return type from size_t to unsigned int

---

Sorry, I didn't really pay much attention to the original function while writing mine. I tend to use size_t when using that variable as a size. I would have used size_t if the function's result was going to be used in the calculation for the size of an array or some such.

Yes, that's why I posted question. I'm interesting to read why he change it. i think there is no particular reason.
Ok, thanks for answering. It's really nice solution.
Thanks

- Micko