err.c

    err_fns_check();
    /*
     * thread_del_item automatically destroys the LHASH if the number of
     * items reaches zero.
     */
    ERRFN(thread_del_item) (&tmp);
}

#ifndef OPENSSL_NO_DEPRECATED
void ERR_remove_state(unsigned long pid)
{
    ERR_remove_thread_state(NULL);
}
#endif

ERR_STATE *ERR_get_state(void)
{
    static ERR_STATE fallback;
    ERR_STATE *ret, tmp, *tmpp = NULL;
    int i;
    CRYPTO_THREADID tid;

    err_fns_check();
    CRYPTO_THREADID_current(&tid);
    CRYPTO_THREADID_cpy(&tmp.tid, &tid);
    ret = ERRFN(thread_get_item) (&tmp);

    /* ret == the error state, if NULL, make a new one */
    if (ret == NULL) {
        ret = (ERR_STATE *)OPENSSL_malloc(sizeof(ERR_STATE));
        if (ret == NULL)
            return (&fallback);
        CRYPTO_THREADID_cpy(&ret->tid, &tid);
        ret->top = 0;
        ret->bottom = 0;
        for (i = 0; i < ERR_NUM_ERRORS; i++) {
            ret->err_data[i] = NULL;
            ret->err_data_flags[i] = 0;
        }
        tmpp = ERRFN(thread_set_item) (ret);
        /* To check if insertion failed, do a get. */
        if (ERRFN(thread_get_item) (ret) != ret) {
            ERR_STATE_free(ret); /* could not insert it */
            return (&fallback);
        }
        /*
         * If a race occurred in this function and we came second, tmpp is
         * the first one that we just replaced.
         */
        if (tmpp)
            ERR_STATE_free(tmpp);
    }
    return ret;
}

int ERR_get_next_error_library(void)
{
    err_fns_check();
    return ERRFN(get_next_lib) ();
}

void ERR_set_error_data(char *data, int flags)
{
    ERR_STATE *es;
    int i;

    es = ERR_get_state();

    i = es->top;
    if (i == 0)
        i = ERR_NUM_ERRORS - 1;

    err_clear_data(es, i);
    es->err_data[i] = data;
    es->err_data_flags[i] = flags;
}

void ERR_add_error_data(int num, ...)
{
    va_list args;
    va_start(args, num);
    ERR_add_error_vdata(num, args);
    va_end(args);
}

void ERR_add_error_vdata(int num, va_list args)
{
    int i, n, s;
    char *str, *p, *a;

    s = 80;
    str = OPENSSL_malloc(s + 1);
    if (str == NULL)
        return;
    str[0] = '\0';

    n = 0;
    for (i = 0; i < num; i++) {
        a = va_arg(args, char *);
        /* ignore NULLs, thanks to Bob Beck <beck@obtuse.com> */
        if (a != NULL) {
            n += strlen(a);
            if (n > s) {
                s = n + 20;
                p = OPENSSL_realloc(str, s + 1);
                if (p == NULL) {
                    OPENSSL_free(str);
                    return;
                } else
                    str = p;
            }
            BUF_strlcat(str, a, (size_t)s + 1);
        }
    }
    ERR_set_error_data(str, ERR_TXT_MALLOCED | ERR_TXT_STRING);
}

int ERR_set_mark(void)
{
    ERR_STATE *es;

    es = ERR_get_state();

    if (es->bottom == es->top)
        return 0;
    es->err_flags[es->top] |= ERR_FLAG_MARK;
    return 1;
}

int ERR_pop_to_mark(void)
{
    ERR_STATE *es;

    es = ERR_get_state();

    while (es->bottom != es->top
           && (es->err_flags[es->top] & ERR_FLAG_MARK) == 0) {
        err_clear(es, es->top);
        es->top -= 1;
        if (es->top == -1)
            es->top = ERR_NUM_ERRORS - 1;
    }

    if (es->bottom == es->top)
        return 0;
    es->err_flags[es->top] &= ~ERR_FLAG_MARK;
    return 1;
}