/*
 *  Error message information
 *
 *  Copyright The Mbed TLS Contributors
 *  SPDX-License-Identifier: Apache-2.0
 *
 *  Licensed under the Apache License, Version 2.0 (the "License"); you may
 *  not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *  http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 */

#include "common.h"

#include "mbedtls/error.h"

#if defined(MBEDTLS_ERROR_C) || defined(MBEDTLS_ERROR_STRERROR_DUMMY)

#if defined(MBEDTLS_ERROR_C)

#if defined(MBEDTLS_PLATFORM_C)
#include "mbedtls/platform.h"
#else
#define mbedtls_snprintf snprintf
#endif

#include <stdio.h>
#include <string.h>

HEADER_INCLUDED

const char * mbedtls_high_level_strerr( int error_code )
{
    int high_level_error_code;

    if( error_code < 0 )
        error_code = -error_code;

    /* Extract the high-level part from the error code. */
    high_level_error_code = error_code & 0xFF80;

    switch( high_level_error_code )
    {
        /* Begin Auto-Generated Code. */
HIGH_LEVEL_CODE_CHECKS
        /* End Auto-Generated Code. */

        default:
            break;
    }

    return( NULL );
}

const char * mbedtls_low_level_strerr( int error_code )
{
    int low_level_error_code;

    if( error_code < 0 )
        error_code = -error_code;

    /* Extract the low-level part from the error code. */
    low_level_error_code = error_code & ~0xFF80;

    switch( low_level_error_code )
    {
        /* Begin Auto-Generated Code. */
LOW_LEVEL_CODE_CHECKS
        /* End Auto-Generated Code. */

        default:
            break;
    }

    return( NULL );
}

void mbedtls_strerror( int ret, char *buf, size_t buflen )
{
    size_t len;
    int use_ret;
    const char * high_level_error_description = NULL;
    const char * low_level_error_description = NULL;

    if( buflen == 0 )
        return;

    memset( buf, 0x00, buflen );

    if( ret < 0 )
        ret = -ret;

    if( ret & 0xFF80 )
    {
        use_ret = ret & 0xFF80;

        // Translate high level error code.
        high_level_error_description = mbedtls_high_level_strerr( ret );

        if( high_level_error_description == NULL )
            mbedtls_snprintf( buf, buflen, "UNKNOWN ERROR CODE (%04X)", (unsigned int) use_ret );
        else
            mbedtls_snprintf( buf, buflen, "%s", high_level_error_description );

#if defined(MBEDTLS_SSL_TLS_C)
        // Early return in case of a fatal error - do not try to translate low
        // level code.
        if(use_ret == -(MBEDTLS_ERR_SSL_FATAL_ALERT_MESSAGE))
            return;
#endif /* MBEDTLS_SSL_TLS_C */
    }

    use_ret = ret & ~0xFF80;

    if( use_ret == 0 )
        return;

    // If high level code is present, make a concatenation between both
    // error strings.
    //
    len = strlen( buf );

    if( len > 0 )
    {
        if( buflen - len < 5 )
            return;

        mbedtls_snprintf( buf + len, buflen - len, " : " );

        buf += len + 3;
        buflen -= len + 3;
    }

    // Translate low level error code.
    low_level_error_description = mbedtls_low_level_strerr( ret );

    if( low_level_error_description == NULL )
        mbedtls_snprintf( buf, buflen, "UNKNOWN ERROR CODE (%04X)", (unsigned int) use_ret );
    else
        mbedtls_snprintf( buf, buflen, "%s", low_level_error_description );
}

#else /* MBEDTLS_ERROR_C */

/*
 * Provide an non-function in case MBEDTLS_ERROR_C is not defined
 */
void mbedtls_strerror( int ret, char *buf, size_t buflen )
{
    ((void) ret);

    if( buflen > 0 )
        buf[0] = '\0';
}

#endif /* MBEDTLS_ERROR_C */

#endif /* MBEDTLS_ERROR_C || MBEDTLS_ERROR_STRERROR_DUMMY */
