/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2024 Arm Ltd
 */

#include <sys/types.h>

#include <machine/cpu.h>
#include <machine/cpufunc.h>

#include <errno.h>
#include <stdint.h>

#include <atf-c.h>

static void critical_enter(void);
static void critical_exit(void);

#include <sys/buf_ring.h>

static void
critical_enter(void)
{
}

static void
critical_exit(void)
{
}

static void *
buf_ring_dequeue_peek(struct buf_ring *br)
{
        void *val;

        val = buf_ring_peek(br);
        if (val != NULL)
                buf_ring_advance_sc(br);
        return (val);
}

static void *
buf_ring_dequeue_peek_clear_sc(struct buf_ring *br)
{
        void *val;

        val = buf_ring_peek_clear_sc(br);
        if (val != NULL)
                buf_ring_advance_sc(br);
        return (val);
}

#define MC_SC_TEST(dequeue_func)                                        \
ATF_TC_WITHOUT_HEAD(dequeue_func);                                      \
ATF_TC_BODY(dequeue_func, tc)                                           \
{                                                                       \
        struct buf_ring *br;                                            \
                                                                        \
        br = buf_ring_alloc(4);                                         \
        ATF_REQUIRE_MSG(br != NULL, "buf_ring_alloc returned NULL");    \
                                                                        \
        ATF_REQUIRE(dequeue_func(br) == NULL);                          \
        ATF_REQUIRE(buf_ring_count(br) == 0);                           \
        ATF_REQUIRE(!buf_ring_full(br));                                \
        ATF_REQUIRE(buf_ring_empty(br));                                \
                                                                        \
        /* Try filling the buf_ring */                                  \
        ATF_REQUIRE(buf_ring_enqueue(br, (void *)1) == 0);              \
        ATF_REQUIRE(buf_ring_enqueue(br, (void *)2) == 0);              \
        ATF_REQUIRE(buf_ring_enqueue(br, (void *)3) == 0);              \
        ATF_REQUIRE(buf_ring_enqueue(br, (void *)4) == ENOBUFS);        \
                                                                        \
        ATF_REQUIRE(buf_ring_count(br) == 3);                           \
        ATF_REQUIRE(buf_ring_full(br));                                 \
        ATF_REQUIRE(!buf_ring_empty(br));                               \
                                                                        \
        /* Partially empty it */                                        \
        ATF_REQUIRE(dequeue_func(br) == (void *)1);                     \
        ATF_REQUIRE(dequeue_func(br) == (void *)2);                     \
                                                                        \
        ATF_REQUIRE(buf_ring_count(br) == 1);                           \
        ATF_REQUIRE(!buf_ring_full(br));                                \
        ATF_REQUIRE(!buf_ring_empty(br));                               \
                                                                        \
        /* Add more items */                                            \
        ATF_REQUIRE(buf_ring_enqueue(br, (void *)5) == 0);              \
        ATF_REQUIRE(buf_ring_count(br) == 2);                           \
                                                                        \
        /* Finish emptying it */                                        \
        ATF_REQUIRE(dequeue_func(br) == (void *)3);                     \
        ATF_REQUIRE(dequeue_func(br) == (void *)5);                     \
        ATF_REQUIRE(dequeue_func(br) == NULL);                          \
                                                                        \
        ATF_REQUIRE(buf_ring_count(br) == 0);                           \
        ATF_REQUIRE(!buf_ring_full(br));                                \
        ATF_REQUIRE(buf_ring_empty(br));                                \
                                                                        \
        for (uintptr_t i = 0; i < 8; i++) {                             \
                ATF_REQUIRE(buf_ring_enqueue(br, (void *)(i + 100)) == 0);  \
                ATF_REQUIRE(buf_ring_enqueue(br, (void *)(i + 200)) == 0);  \
                ATF_REQUIRE(buf_ring_enqueue(br, (void *)(i + 300)) == 0);  \
                ATF_REQUIRE(buf_ring_count(br) == 3);                   \
                ATF_REQUIRE(dequeue_func(br) == (void *)(i + 100));     \
                ATF_REQUIRE(dequeue_func(br) == (void *)(i + 200));     \
                ATF_REQUIRE(dequeue_func(br) == (void *)(i + 300));     \
                                                                        \
                ATF_REQUIRE(!buf_ring_full(br));                        \
                ATF_REQUIRE(buf_ring_empty(br));                        \
        }                                                               \
                                                                        \
        buf_ring_free(br);                                              \
}

MC_SC_TEST(buf_ring_dequeue_sc)
MC_SC_TEST(buf_ring_dequeue_mc)
MC_SC_TEST(buf_ring_dequeue_peek)
MC_SC_TEST(buf_ring_dequeue_peek_clear_sc)

ATF_TC_WITHOUT_HEAD(overflow);
ATF_TC_BODY(overflow, tc)
{
        struct buf_ring *br;

        br = buf_ring_alloc(4);
        ATF_REQUIRE_MSG(br != NULL, "buf_ring_alloc returned NULL");

        br->br_prod_head = br->br_cons_head = br->br_prod_tail =
            br->br_cons_tail = UINT32_MAX - 1;
        ATF_REQUIRE(buf_ring_count(br) == 0);
        ATF_REQUIRE(!buf_ring_full(br));
        ATF_REQUIRE(buf_ring_empty(br));

        ATF_REQUIRE(buf_ring_enqueue(br, (void *)1) == 0);
        ATF_REQUIRE(buf_ring_count(br) == 1);
        ATF_REQUIRE(!buf_ring_full(br));
        ATF_REQUIRE(!buf_ring_empty(br));

        ATF_REQUIRE(buf_ring_enqueue(br, (void *)2) == 0);
        ATF_REQUIRE(buf_ring_count(br) == 2);
        ATF_REQUIRE(!buf_ring_full(br));
        ATF_REQUIRE(!buf_ring_empty(br));

        ATF_REQUIRE(buf_ring_enqueue(br, (void *)3) == 0);
        ATF_REQUIRE(buf_ring_count(br) == 3);
        ATF_REQUIRE(buf_ring_full(br));
        ATF_REQUIRE(!buf_ring_empty(br));

        ATF_REQUIRE(br->br_prod_head == 1);
        ATF_REQUIRE(br->br_prod_tail == 1);
        ATF_REQUIRE(br->br_cons_head == UINT32_MAX - 1);
        ATF_REQUIRE(br->br_cons_tail == UINT32_MAX - 1);

        ATF_REQUIRE(buf_ring_dequeue_sc(br) == (void *)1);
        ATF_REQUIRE(buf_ring_count(br) == 2);
        ATF_REQUIRE(!buf_ring_full(br));
        ATF_REQUIRE(!buf_ring_empty(br));

        ATF_REQUIRE(buf_ring_dequeue_sc(br) == (void *)2);
        ATF_REQUIRE(buf_ring_count(br) == 1);
        ATF_REQUIRE(!buf_ring_full(br));
        ATF_REQUIRE(!buf_ring_empty(br));

        ATF_REQUIRE(buf_ring_dequeue_sc(br) == (void *)3);
        ATF_REQUIRE(buf_ring_count(br) == 0);
        ATF_REQUIRE(!buf_ring_full(br));
        ATF_REQUIRE(buf_ring_empty(br));

        buf_ring_free(br);
}

ATF_TP_ADD_TCS(tp)
{
        ATF_TP_ADD_TC(tp, buf_ring_dequeue_sc);
        ATF_TP_ADD_TC(tp, buf_ring_dequeue_mc);
        ATF_TP_ADD_TC(tp, buf_ring_dequeue_peek);
        ATF_TP_ADD_TC(tp, buf_ring_dequeue_peek_clear_sc);
        ATF_TP_ADD_TC(tp, overflow);
        return (atf_no_error());
}