// SPDX-License-Identifier: GPL-2.0
#include <malloc.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include "utils.h"

#define SIZE 256
#define ITERATIONS 1000
#define ITERATIONS_BENCH 100000

int test_strlen(const void *s);

/* test all offsets and lengths */
static void test_one(char *s)
{
        unsigned long offset;

        for (offset = 0; offset < SIZE; offset++) {
                int x, y;
                unsigned long i;

                y = strlen(s + offset);
                x = test_strlen(s + offset);

                if (x != y) {
                        printf("strlen() returned %d, should have returned %d (%p offset %ld)\n", x, y, s, offset);

                        for (i = offset; i < SIZE; i++)
                                printf("%02x ", s[i]);
                        printf("\n");
                }
        }
}

static void bench_test(char *s)
{
        struct timespec ts_start, ts_end;
        int i;

        clock_gettime(CLOCK_MONOTONIC, &ts_start);

        for (i = 0; i < ITERATIONS_BENCH; i++)
                test_strlen(s);

        clock_gettime(CLOCK_MONOTONIC, &ts_end);

        printf("len %3.3d : time = %.6f\n", test_strlen(s), ts_end.tv_sec - ts_start.tv_sec + (ts_end.tv_nsec - ts_start.tv_nsec) / 1e9);
}

static int testcase(void)
{
        char *s;
        unsigned long i;

        s = memalign(128, SIZE);
        if (!s) {
                perror("memalign");
                exit(1);
        }

        srandom(1);

        memset(s, 0, SIZE);
        for (i = 0; i < SIZE; i++) {
                char c;

                do {
                        c = random() & 0x7f;
                } while (!c);
                s[i] = c;
                test_one(s);
        }

        for (i = 0; i < ITERATIONS; i++) {
                unsigned long j;

                for (j = 0; j < SIZE; j++) {
                        char c;

                        do {
                                c = random() & 0x7f;
                        } while (!c);
                        s[j] = c;
                }
                for (j = 0; j < sizeof(long); j++) {
                        s[SIZE - 1 - j] = 0;
                        test_one(s);
                }
        }

        for (i = 0; i < SIZE; i++) {
                char c;

                do {
                        c = random() & 0x7f;
                } while (!c);
                s[i] = c;
        }

        bench_test(s);

        s[16] = 0;
        bench_test(s);

        s[8] = 0;
        bench_test(s);

        s[4] = 0;
        bench_test(s);

        s[3] = 0;
        bench_test(s);

        s[2] = 0;
        bench_test(s);

        s[1] = 0;
        bench_test(s);

        return 0;
}

int main(void)
{
        return test_harness(testcase, "strlen");
}