/******************************************************************************

 *

 * Project:  VSI Virtual File System

 * Purpose:  Implement an error system for reporting file system errors.

 *           Filesystem errors need to be handled separately from the

 *           CPLError architecture because they are potentially ignored.

 * Author:   Rob Emanuele, rdemanuele at gmail.com

 *

 ******************************************************************************

 * Copyright (c) 2016, Rob Emanuele <rdemanuele at gmail.com>

 *

 * SPDX-License-Identifier: MIT

 ****************************************************************************/

#include "cpl_vsi_error.h"

#include <cstdarg>

#include <cstdio>

#include "cpl_config.h"

#include "cpl_conv.h"

#include "cpl_error.h"

#include "cpl_multiproc.h"

#include "cpl_string.h"

#include "cpl_vsi.h"

#if !defined(va_copy) && defined(__va_copy)

#define va_copy __va_copy

#endif

// TODO(rouault): Why is this here?

#if !defined(_WIN32)

#include <string.h>

#endif

#define TIMESTAMP_DEBUG

// #define MEMORY_DEBUG

constexpr int DEFAULT_LAST_ERR_MSG_SIZE =

#if !defined(HAVE_VSNPRINTF)

    20000

#else

    500

#endif

    ;

typedef struct

{

    VSIErrorNum nLastErrNo;

    int nLastErrMsgMax;

    char szLastErrMsg[DEFAULT_LAST_ERR_MSG_SIZE];

    // Do not add anything here. szLastErrMsg must be the last field. See

    // CPLRealloc() below.

} VSIErrorContext;

/************************************************************************/

/*                         CPLGetErrorContext()                         */

/************************************************************************/

static VSIErrorContext *VSIGetErrorContext()

{

    int bError = FALSE;

    VSIErrorContext *psCtx = reinterpret_cast<VSIErrorContext *>(

        CPLGetTLSEx(CTLS_VSIERRORCONTEXT, &bError));

    if (bError)

        return nullptr;

    if (psCtx == nullptr)

    {

        psCtx = static_cast<VSIErrorContext *>(

            VSICalloc(sizeof(VSIErrorContext), 1));

        if (psCtx == nullptr)

        {

            fprintf(stderr, /*ok*/

                    "Out of memory attempting to record a VSI error.\n");

            return nullptr;

        }

        psCtx->nLastErrNo = VSIE_None;

        psCtx->nLastErrMsgMax = sizeof(psCtx->szLastErrMsg);

        CPLSetTLS(CTLS_VSIERRORCONTEXT, psCtx, TRUE);

    }

    return psCtx;

}

/************************************************************************/

/*                             VSIErrorV()                              */

/************************************************************************/

static void VSIErrorV(VSIErrorNum err_no, const char *fmt, va_list args)

{

    VSIErrorContext *psCtx = VSIGetErrorContext();

    if (psCtx == nullptr)

        return;

/* -------------------------------------------------------------------- */

/*      Expand the error message                                        */

/* -------------------------------------------------------------------- */

#if defined(HAVE_VSNPRINTF)

    {

        va_list wrk_args;

#ifdef va_copy

        va_copy(wrk_args, args);

#else

        wrk_args = args;

#endif

        int nPreviousSize = 0;

        int nPR = 0;

        while (((nPR = CPLvsnprintf(psCtx->szLastErrMsg + nPreviousSize,

                                    psCtx->nLastErrMsgMax - nPreviousSize, fmt,

                                    wrk_args)) == -1 ||

                nPR >= psCtx->nLastErrMsgMax - nPreviousSize - 1) &&

               psCtx->nLastErrMsgMax < 1000000)

        {

#ifdef va_copy

            va_end(wrk_args);

            va_copy(wrk_args, args);

#else

            wrk_args = args;

#endif

            psCtx->nLastErrMsgMax *= 3;

            psCtx = static_cast<VSIErrorContext *>(CPLRealloc(

                psCtx, sizeof(VSIErrorContext) - DEFAULT_LAST_ERR_MSG_SIZE +

                           psCtx->nLastErrMsgMax + 1));

            CPLSetTLS(CTLS_VSIERRORCONTEXT, psCtx, TRUE);

        }

        va_end(wrk_args);

    }

#else  // !HAVE_VSNPRINTF

    CPLvsnprintf(psCtx->szLastErrMsg, psCtx->nLastErrMsgMax, fmt, args);

#endif

    psCtx->nLastErrNo = err_no;

}

/**********************************************************************

 *                          VSIError()

 **********************************************************************/

/**

 * Report a VSI filesystem error.

 *

 * This function records an error in the filesystem that may or may not be

 * used in the future, for example converted into a CPLError. This allows

 * filesystem errors to be available to error handling functionality, but

 * reported only when necessary.

 *

 * @param err_no the error number (VSIE_*) from cpl_vsi_error.h.

 * @param fmt a printf() style format string.  Any additional arguments

 * will be treated as arguments to fill in this format in a manner

 * similar to printf().

 */

void VSIError(VSIErrorNum err_no, CPL_FORMAT_STRING(const char *fmt), ...)

{

    va_list args;

    // Expand the error message.

    va_start(args, fmt);

    VSIErrorV(err_no, fmt, args);

    va_end(args);

}

/**********************************************************************

 *                          VSIErrorReset()

 **********************************************************************/

/**

 * Erase any traces of previous errors.

 *

 * This is used to clear out the latest file system error when it is either

 * translated into a CPLError call or when it is determined to be ignorable.

 */

void CPL_STDCALL VSIErrorReset()

{

    VSIErrorContext *psCtx = VSIGetErrorContext();

    if (psCtx == nullptr)

        return;

    psCtx->nLastErrNo = VSIE_None;

    psCtx->szLastErrMsg[0] = '\0';

}

/**********************************************************************

 *                          VSIGetLastErrorNo()

 **********************************************************************/

/**

 * Fetch the last error number.

 *

 * Fetches the last error number posted with VSIError(), that hasn't

 * been cleared by VSIErrorReset().  This is the error number, not the error

 * class.

 *

 * @return the error number of the last error to occur, or VSIE_None (0)

 * if there are no posted errors.

 */

VSIErrorNum CPL_STDCALL VSIGetLastErrorNo()

{

    VSIErrorContext *psCtx = VSIGetErrorContext();

    if (psCtx == nullptr)

        return 0;

    return psCtx->nLastErrNo;

}

/**********************************************************************

 *                          VSIGetLastErrorMsg()

 **********************************************************************/

/**

 * Get the last error message.

 *

 * Fetches the last error message posted with VSIError(), that hasn't

 * been cleared by VSIErrorReset().  The returned pointer is to an internal

 * string that should not be altered or freed.

 *

 * @return the last error message, or NULL if there is no posted error

 * message.

 */

const char *CPL_STDCALL VSIGetLastErrorMsg()

{

    VSIErrorContext *psCtx = VSIGetErrorContext();

    if (psCtx == nullptr)

        return "";

    return psCtx->szLastErrMsg;

}

/**********************************************************************

 *                     VSIErrorNumToString()

 **********************************************************************/

/** Translate a VSI error number into a string.

 *

 * @since GDAL 3.12

 */

const char *VSIErrorNumToString(int eErr)

{

#define CASE(x)                                                                \

    case VSIE_##x:                                                             \

        return #x;

    switch (eErr)

    {

        CASE(None)

        CASE(FileError)

        CASE(HttpError)

        CASE(ObjectStorageGenericError)

        CASE(AccessDenied)

        CASE(BucketNotFound)

        CASE(ObjectNotFound)

        CASE(InvalidCredentials)

        CASE(SignatureDoesNotMatch)

        default:

            break;

    }

#undef CASE

    CPLAssert(false);

    return "UnknownError";

}

/**********************************************************************

 *                          VSItoCPLError()

 **********************************************************************/

/**

 * Translate the VSI error into a CPLError call

 *

 * If there is a VSIError that is set, translate it to a CPLError call

 * with the given CPLErr error class, and either an appropriate CPLErrorNum

 * given the VSIErrorNum, or the given default CPLErrorNum.

 *

 * @return TRUE if a CPLError was issued, or FALSE if not.

 */

int CPL_STDCALL VSIToCPLError(CPLErr eErrClass, CPLErrorNum eDefaultErrorNo)

{

    const int err = VSIGetLastErrorNo();

    switch (err)

    {

        case VSIE_None:

            return FALSE;

        case VSIE_FileError:

            CPLError(eErrClass, eDefaultErrorNo, "%s", VSIGetLastErrorMsg());

            break;

        case VSIE_HttpError:

            CPLError(eErrClass, CPLE_HttpResponse, "%s", VSIGetLastErrorMsg());

            break;

        case VSIE_ObjectStorageGenericError:

            CPLError(eErrClass, CPLE_ObjectStorageGenericError, "%s",

                     VSIGetLastErrorMsg());

            break;

        case VSIE_AccessDenied:

            CPLError(eErrClass, CPLE_AccessDenied, "%s: %s",

                     VSIErrorNumToString(err), VSIGetLastErrorMsg());

            break;

        case VSIE_BucketNotFound:

            CPLError(eErrClass, CPLE_BucketNotFound, "%s: %s",

                     VSIErrorNumToString(err), VSIGetLastErrorMsg());

            break;

        case VSIE_ObjectNotFound:

            CPLError(eErrClass, CPLE_ObjectNotFound, "%s: %s",

                     VSIErrorNumToString(err), VSIGetLastErrorMsg());

            break;

        case VSIE_InvalidCredentials:

            CPLError(eErrClass, CPLE_InvalidCredentials, "%s: %s",

                     VSIErrorNumToString(err), VSIGetLastErrorMsg());

            break;

        case VSIE_SignatureDoesNotMatch:

            CPLError(eErrClass, CPLE_SignatureDoesNotMatch, "%s: %s",

                     VSIErrorNumToString(err), VSIGetLastErrorMsg());

            break;

        default:

            CPLError(eErrClass, CPLE_HttpResponse,

                     "A filesystem error with code %d occurred", err);

            break;

    }

    return TRUE;

}

/**********************************************************************

 *                        VSIToCPLErrorWithMsg()

 **********************************************************************/

/**

 * Translate the VSI error into a CPLError call

 *

 * If there is a VSIError that is set, translate it to a CPLError call

 * with the given CPLErr error class, and either an appropriate CPLErrorNum

 * given the VSIErrorNum, or the given default CPLErrorNum.

 */

void VSIToCPLErrorWithMsg(CPLErr eErrClass, CPLErrorNum eDefaultErrorNo,

                          const char *pszMsg)

{

    const int err = VSIGetLastErrorNo();

    switch (err)

    {

        case VSIE_None:

            CPLError(eErrClass, eDefaultErrorNo, "%s", pszMsg);

            break;

        case VSIE_FileError:

            CPLError(eErrClass, eDefaultErrorNo, "%s: %s", pszMsg,

                     VSIGetLastErrorMsg());

            break;

        case VSIE_HttpError:

            CPLError(eErrClass, CPLE_HttpResponse, "%s: %s", pszMsg,

                     VSIGetLastErrorMsg());

            break;

        case VSIE_ObjectStorageGenericError:

            CPLError(eErrClass, CPLE_ObjectStorageGenericError, "%s: %s",

                     pszMsg, VSIGetLastErrorMsg());

            break;

        case VSIE_AccessDenied:

            CPLError(eErrClass, CPLE_AccessDenied, "%s: %s", pszMsg,

                     VSIGetLastErrorMsg());

            break;

        case VSIE_BucketNotFound:

            CPLError(eErrClass, CPLE_BucketNotFound, "%s: %s", pszMsg,

                     VSIGetLastErrorMsg());

            break;

        case VSIE_ObjectNotFound:

            CPLError(eErrClass, CPLE_ObjectNotFound, "%s: %s", pszMsg,

                     VSIGetLastErrorMsg());

            break;

        case VSIE_InvalidCredentials:

            CPLError(eErrClass, CPLE_InvalidCredentials, "%s: %s", pszMsg,

                     VSIGetLastErrorMsg());

            break;

        case VSIE_SignatureDoesNotMatch:

            CPLError(eErrClass, CPLE_SignatureDoesNotMatch, "%s: %s", pszMsg,

                     VSIGetLastErrorMsg());

            break;

        default:

            CPLError(eErrClass, CPLE_HttpResponse,

                     "%s: A filesystem error with code %d occurred", pszMsg,

                     err);

            break;

    }

}