/*
 * Copyright 1995-2026 The OpenSSL Project Authors. All Rights Reserved.
 *
 * Licensed under the Apache License 2.0 (the "License").  You may not use
 * this file except in compliance with the License.  You can obtain a copy
 * in the file LICENSE in the source distribution or at
 * https://www.openssl.org/source/license.html
 */

#include <string.h>
#include <openssl/err.h>
#include <openssl/e_os2.h>
#include "internal/err.h"

#define ERR_FLAG_MARK 0x01
#define ERR_FLAG_CLEAR 0x02

struct err_state_st {
    int err_flags[ERR_NUM_ERRORS];
    int err_marks[ERR_NUM_ERRORS];
    unsigned long err_buffer[ERR_NUM_ERRORS];
    char *err_data[ERR_NUM_ERRORS];
    size_t err_data_size[ERR_NUM_ERRORS];
    int err_data_flags[ERR_NUM_ERRORS];
    char *err_file[ERR_NUM_ERRORS];
    int err_line[ERR_NUM_ERRORS];
    char *err_func[ERR_NUM_ERRORS];
    int top, bottom;
};

static ossl_inline void err_get_slot(ERR_STATE *es)
{
    es->top = (es->top + 1) % ERR_NUM_ERRORS;
    if (es->top == es->bottom)
        es->bottom = (es->bottom + 1) % ERR_NUM_ERRORS;
}

static ossl_inline void err_clear_data(ERR_STATE *es, size_t i, int deall)
{
    if (es->err_data_flags[i] & ERR_TXT_MALLOCED) {
        if (deall) {
            OPENSSL_free(es->err_data[i]);
            es->err_data[i] = NULL;
            es->err_data_size[i] = 0;
            es->err_data_flags[i] = 0;
        } else if (es->err_data[i] != NULL) {
            es->err_data[i][0] = '\0';
            es->err_data_flags[i] = ERR_TXT_MALLOCED;
        }
    } else {
        es->err_data[i] = NULL;
        es->err_data_size[i] = 0;
        es->err_data_flags[i] = 0;
    }
}

static ossl_inline void err_set_error(ERR_STATE *es, size_t i,
    int lib, int reason)
{
    es->err_buffer[i] = lib == ERR_LIB_SYS
        ? (unsigned int)(ERR_SYSTEM_FLAG | reason)
        : ERR_PACK(lib, 0, reason);
}

static ossl_inline void err_set_debug(ERR_STATE *es, size_t i,
    const char *file, int line,
    const char *fn)
{
    /*
     * We dup the file and fn strings because they may be provider owned. If the
     * provider gets unloaded, they may not be valid anymore.
     */
    OPENSSL_free(es->err_file[i]);
    if (file == NULL || file[0] == '\0')
        es->err_file[i] = NULL;
    else if ((es->err_file[i] = CRYPTO_malloc(strlen(file) + 1,
                  NULL, 0))
        != NULL)
        /* We cannot use OPENSSL_strdup due to possible recursion */
        strcpy(es->err_file[i], file);

    es->err_line[i] = line;
    OPENSSL_free(es->err_func[i]);
    if (fn == NULL || fn[0] == '\0')
        es->err_func[i] = NULL;
    else if ((es->err_func[i] = CRYPTO_malloc(strlen(fn) + 1,
                  NULL, 0))
        != NULL)
        strcpy(es->err_func[i], fn);
}

static ossl_inline void err_set_data(ERR_STATE *es, size_t i,
    void *data, size_t datasz, int flags)
{
    if ((es->err_data_flags[i] & ERR_TXT_MALLOCED) != 0)
        OPENSSL_free(es->err_data[i]);
    es->err_data[i] = data;
    es->err_data_size[i] = datasz;
    es->err_data_flags[i] = flags;
}

static ossl_inline void err_clear(ERR_STATE *es, size_t i, int deall)
{
    err_clear_data(es, i, (deall));
    es->err_marks[i] = 0;
    es->err_flags[i] = 0;
    es->err_buffer[i] = 0;
    es->err_line[i] = -1;
    OPENSSL_free(es->err_file[i]);
    es->err_file[i] = NULL;
    OPENSSL_free(es->err_func[i]);
    es->err_func[i] = NULL;
}

ERR_STATE *ossl_err_get_state_int(void);
void ossl_err_string_int(unsigned long e, const char *func,
    char *buf, size_t len);
