Hi,

In case someone is interested, else please ignore (just sending on
public domain for other people if they do web search) [Tested on
latest glibc - glibc-2.33].

I have done final testing with long needles. I modified bench-strstr.c
and included my algorithm in it.

Attached are the diff, analysis.xlsx, and original bench-strstr.out.

Below is my code:

==============================================================================================

// Choudhary algorithm
static char *
chal(char *text, char *pattern)
{

#define false 0
#define true 1
#define ALPHABET_SIZE 256

    long i = 0;
    long index = 0;
    long end_index = 0;
    int not_found = false;

    long text_len = strlen(text);
    long pattern_len = strlen(pattern);

    long pi_44 = pattern_len - 1;
    long pi_34 = (3 * pattern_len) / 4;
    long pi_24 = pattern_len / 2;
    long pi_14 = pattern_len / 4;

    long fps = 0;
    long skip_table[ALPHABET_SIZE] = {0};

    // preprocess pattern and fill skip_table
    for (i = 0; i < pattern_len; i++) {
        skip_table[(int)(pattern[i])] = pattern_len - 1 - i;
    }

    // now search
    for (i = 0; i < text_len; i++) {

        if ((text_len - i) < pattern_len) {
                //printf("\tfps = %ld\n", fps);
            return NULL;
            //return -1;
        }

        if (pattern[pi_44] != text[i + pi_44]) {
            if (skip_table[(int)(text[i + pi_44])] > 0) {
                i = i + skip_table[(int)(text[i + pi_44])] - 1;
            }
            continue;
        }

        if (pattern[0] != text[i]) {
            continue;
        }

        if (pattern[pi_24] != text[i + pi_24]) {
            continue;
        }

        if (pattern[pi_34] != text[i + pi_34]) {
            continue;
        }

        if (pattern[pi_14] != text[i + pi_14]) {
            continue;
        }

        fps = fps + 1;
        end_index = i + pi_44;
        not_found = false;

        for (index = i; index <= end_index; index++) {
            if (text[index] != pattern[index - i]) {
                not_found = true;
                break;
            }
        } // end of inner for loop

        if (not_found == false) { // match is found
            //printf("\tfps = %ld\n", fps);
            return (text + i);
            //return i;
        }

    } // end of outer for loop

                //printf("\tfps = %ld\n", fps);
    return NULL;
    //return -1;

} // end of chal

==============================================================================================

Amit