// SPDX-License-Identifier: GPL-2.0
#include <perf/threadmap.h>
#include <stdlib.h>
#include <linux/refcount.h>
#include <internal/threadmap.h>
#include <string.h>
#include <asm/bug.h>
#include <stdio.h>

static void perf_thread_map__reset(struct perf_thread_map *map, int start, int nr)
{
        size_t size = (nr - start) * sizeof(map->map[0]);

        memset(&map->map[start], 0, size);
        map->err_thread = -1;
}

struct perf_thread_map *perf_thread_map__realloc(struct perf_thread_map *map, int nr)
{
        size_t size = sizeof(*map) + sizeof(map->map[0]) * nr;
        int start = map ? map->nr : 0;

        map = realloc(map, size);
        /*
         * We only realloc to add more items, let's reset new items.
         */
        if (map)
                perf_thread_map__reset(map, start, nr);

        return map;
}

#define thread_map__alloc(__nr) perf_thread_map__realloc(NULL, __nr)

void perf_thread_map__set_pid(struct perf_thread_map *map, int idx, pid_t pid)
{
        map->map[idx].pid = pid;
}

char *perf_thread_map__comm(struct perf_thread_map *map, int idx)
{
        return map->map[idx].comm;
}

struct perf_thread_map *perf_thread_map__new_array(int nr_threads, pid_t *array)
{
        struct perf_thread_map *threads = thread_map__alloc(nr_threads);
        int i;

        if (!threads)
                return NULL;

        for (i = 0; i < nr_threads; i++)
                perf_thread_map__set_pid(threads, i, array ? array[i] : -1);

        threads->nr = nr_threads;
        refcount_set(&threads->refcnt, 1);

        return threads;
}

struct perf_thread_map *perf_thread_map__new_dummy(void)
{
        return perf_thread_map__new_array(1, NULL);
}

static void perf_thread_map__delete(struct perf_thread_map *threads)
{
        if (threads) {
                int i;

                WARN_ONCE(refcount_read(&threads->refcnt) != 0,
                          "thread map refcnt unbalanced\n");
                for (i = 0; i < threads->nr; i++)
                        free(perf_thread_map__comm(threads, i));
                free(threads);
        }
}

struct perf_thread_map *perf_thread_map__get(struct perf_thread_map *map)
{
        if (map)
                refcount_inc(&map->refcnt);
        return map;
}

void perf_thread_map__put(struct perf_thread_map *map)
{
        if (map && refcount_dec_and_test(&map->refcnt))
                perf_thread_map__delete(map);
}

int perf_thread_map__nr(struct perf_thread_map *threads)
{
        return threads ? threads->nr : 1;
}

pid_t perf_thread_map__pid(struct perf_thread_map *map, int idx)
{
        if (!map) {
                assert(idx == 0);
                return -1;
        }

        return map->map[idx].pid;
}

int perf_thread_map__idx(struct perf_thread_map *threads, pid_t pid)
{
        if (!threads)
                return pid == -1 ? 0 : -1;

        for (int i = 0; i < threads->nr; ++i) {
                if (threads->map[i].pid == pid)
                        return i;
        }
        return -1;
}