// SPDX-License-Identifier: GPL-2.0
#include <test_progs.h>
#include "test_probe_read_user_str.skel.h"

static const char str1[] = "mestring";
static const char str2[] = "mestringalittlebigger";
static const char str3[] = "mestringblubblubblubblubblub";

static int test_one_str(struct test_probe_read_user_str *skel, const char *str,
                        size_t len)
{
        int err, duration = 0;
        char buf[256];

        /* Ensure bytes after string are ones */
        memset(buf, 1, sizeof(buf));
        memcpy(buf, str, len);

        /* Give prog our userspace pointer */
        skel->bss->user_ptr = buf;

        /* Trigger tracepoint */
        usleep(1);

        /* Did helper fail? */
        if (CHECK(skel->bss->ret < 0, "prog_ret", "prog returned: %ld\n",
                  skel->bss->ret))
                return 1;

        /* Check that string was copied correctly */
        err = memcmp(skel->bss->buf, str, len);
        if (CHECK(err, "memcmp", "prog copied wrong string"))
                return 1;

        /* Now check that no extra trailing bytes were copied */
        memset(buf, 0, sizeof(buf));
        err = memcmp(skel->bss->buf + len, buf, sizeof(buf) - len);
        if (CHECK(err, "memcmp", "trailing bytes were not stripped"))
                return 1;

        return 0;
}

void test_probe_read_user_str(void)
{
        struct test_probe_read_user_str *skel;
        int err, duration = 0;

        skel = test_probe_read_user_str__open_and_load();
        if (CHECK(!skel, "test_probe_read_user_str__open_and_load",
                  "skeleton open and load failed\n"))
                return;

        /* Give pid to bpf prog so it doesn't read from anyone else */
        skel->bss->pid = getpid();

        err = test_probe_read_user_str__attach(skel);
        if (CHECK(err, "test_probe_read_user_str__attach",
                  "skeleton attach failed: %d\n", err))
                goto out;

        if (test_one_str(skel, str1, sizeof(str1)))
                goto out;
        if (test_one_str(skel, str2, sizeof(str2)))
                goto out;
        if (test_one_str(skel, str3, sizeof(str3)))
                goto out;

out:
        test_probe_read_user_str__destroy(skel);
}