/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
/*
 * pkix_error.c
 *
 * Error Object Functions
 *
 */

#include "pkix_error.h"

#undef PKIX_ERRORENTRY

#define PKIX_ERRORENTRY(name,desc,nsserr) #desc

#if defined PKIX_ERROR_DESCRIPTION

const char * const PKIX_ErrorText[] =
{
#include "pkix_errorstrings.h"
};

#else

#include "prprf.h"

#endif /* PKIX_ERROR_DESCRIPTION */

extern const PKIX_Int32 PKIX_PLErrorIndex[];

/* --Private-Functions-------------------------------------------- */

/*
 * FUNCTION: pkix_Error_Equals
 * (see comments for PKIX_PL_EqualsCallback in pkix_pl_system.h)
 */
static PKIX_Error *
pkix_Error_Equals(
        PKIX_PL_Object *firstObject,
        PKIX_PL_Object *secondObject,
        PKIX_Boolean *pResult,
        void *plContext)
{
        PKIX_Error *firstError = NULL;
        PKIX_Error *secondError = NULL;
        PKIX_Error *firstCause = NULL;
        PKIX_Error *secondCause = NULL;
        PKIX_PL_Object *firstInfo = NULL;
        PKIX_PL_Object *secondInfo = NULL;
        PKIX_ERRORCLASS firstClass, secondClass;
        PKIX_UInt32 secondType;
        PKIX_Boolean boolResult, unequalFlag;

        PKIX_ENTER(ERROR, "pkix_Error_Equals");
        PKIX_NULLCHECK_THREE(firstObject, secondObject, pResult);

        unequalFlag = PKIX_FALSE;

        /* First just compare pointer values to save time */
        if (firstObject == secondObject) {
                *pResult = PKIX_TRUE;
                goto cleanup;
        } else {
                /* Result will only be set to true if all tests pass */
                *pResult = PKIX_FALSE;
        }

        PKIX_CHECK(pkix_CheckType(firstObject, PKIX_ERROR_TYPE, plContext),
                    PKIX_FIRSTOBJECTNOTANERROROBJECT);

        PKIX_CHECK(PKIX_PL_Object_GetType
                    (secondObject, &secondType, plContext),
                    PKIX_ERRORGETTINGSECONDOBJECTTYPE);

        /* If types differ, then return false. Result is already set */
        if (secondType != PKIX_ERROR_TYPE) goto cleanup;

        /* It is safe to cast to PKIX_Error */
        firstError = (PKIX_Error *) firstObject;
        secondError = (PKIX_Error *) secondObject;

        /* Compare error codes */
        firstClass = firstError->errClass;
        secondClass = secondError->errClass;

        /* If codes differ, return false. Result is already set */
        if (firstClass != secondClass) goto cleanup;

        /* Compare causes */
        firstCause = firstError->cause;
        secondCause = secondError->cause;

        /* Ensure that either both or none of the causes are NULL */
        if (((firstCause != NULL) && (secondCause == NULL))||
            ((firstCause == NULL) && (secondCause != NULL)))
                unequalFlag = PKIX_TRUE;

        if ((firstCause != NULL) && (secondCause != NULL)) {
                PKIX_CHECK(PKIX_PL_Object_Equals
                            ((PKIX_PL_Object*)firstCause,
                            (PKIX_PL_Object*)secondCause,
                            &boolResult,
                            plContext),
                            PKIX_ERRORINRECURSIVEEQUALSCALL);

                /* Set the unequalFlag so that we return after dec refing */
                if (boolResult == 0) unequalFlag = PKIX_TRUE;
        }

        /* If the cause errors are not equal, return null */
        if (unequalFlag) goto cleanup;

        /* Compare info fields */
        firstInfo = firstError->info;
        secondInfo = secondError->info;

        if (firstInfo != secondInfo) goto cleanup;

        /* Ensure that either both or none of the infos are NULL */
        if (((firstInfo != NULL) && (secondInfo == NULL))||
            ((firstInfo == NULL) && (secondInfo != NULL)))
                unequalFlag = PKIX_TRUE;

        if ((firstInfo != NULL) && (secondInfo != NULL)) {

                PKIX_CHECK(PKIX_PL_Object_Equals
                            ((PKIX_PL_Object*)firstInfo,
                            (PKIX_PL_Object*)secondInfo,
                            &boolResult,
                            plContext),
                            PKIX_ERRORINRECURSIVEEQUALSCALL);

                /* Set the unequalFlag so that we return after dec refing */
                if (boolResult == 0) unequalFlag = PKIX_TRUE;
        }

        /* If the infos are not equal, return null */
        if (unequalFlag) goto cleanup;


        /* Compare descs */
        if (firstError->errCode != secondError->errCode) {
                unequalFlag = PKIX_TRUE;
        }

        if (firstError->plErr != secondError->plErr) {
                unequalFlag = PKIX_TRUE;
        }

        /* If the unequalFlag was set, return false */
        if (unequalFlag) goto cleanup;

        /* Errors are equal in all fields at this point */
        *pResult = PKIX_TRUE;

cleanup:

        PKIX_RETURN(ERROR);
}

/*
 * FUNCTION: pkix_Error_Destroy
 * (see comments for PKIX_PL_DestructorCallback in pkix_pl_system.h)
 */
static PKIX_Error *
pkix_Error_Destroy(
        PKIX_PL_Object *object,
        void *plContext)
{
        PKIX_Error *error = NULL;

        PKIX_ENTER(ERROR, "pkix_Error_Destroy");
        PKIX_NULLCHECK_ONE(object);

        PKIX_CHECK(pkix_CheckType(object, PKIX_ERROR_TYPE, plContext),
                PKIX_OBJECTNOTANERROR);

        error = (PKIX_Error *)object;

        PKIX_DECREF(error->cause);

        PKIX_DECREF(error->info);

cleanup:

        PKIX_RETURN(ERROR);
}


/* XXX This is not thread safe */
static PKIX_UInt32 pkix_error_cause_depth = 1;

/*
 * FUNCTION: pkix_Error_ToString
 * (see comments for PKIX_PL_ToStringCallback in pkix_pl_system.h)
 */
static PKIX_Error *
pkix_Error_ToString(
        PKIX_PL_Object *object,
        PKIX_PL_String **pString,
        void *plContext)
{
        PKIX_Error *error = NULL;
        PKIX_Error *cause = NULL;
        PKIX_PL_String *desc = NULL;
        PKIX_PL_String *formatString = NULL;
        PKIX_PL_String *causeString = NULL;
        PKIX_PL_String *optCauseString = NULL;
        PKIX_PL_String *errorNameString = NULL;
        char *format = NULL;
        PKIX_ERRORCLASS errClass;

        PKIX_ENTER(ERROR, "pkix_Error_ToString");
        PKIX_NULLCHECK_TWO(object, pString);

        PKIX_CHECK(pkix_CheckType(object, PKIX_ERROR_TYPE, plContext),
                PKIX_OBJECTNOTANERROR);

        error = (PKIX_Error *)object;

        /* Get this error's errClass, description and the string of its cause */
        errClass = error->errClass;

        /* Get the description string */
        PKIX_Error_GetDescription(error, &desc, plContext);
            
        /* Get the cause */
        cause = error->cause;

        /* Get the causes's description string */
        if (cause != NULL) {
                pkix_error_cause_depth++;

                /* Get the cause string */
                PKIX_CHECK(PKIX_PL_Object_ToString
                            ((PKIX_PL_Object*)cause, &causeString, plContext),
                            PKIX_ERRORGETTINGCAUSESTRING);

                format = "\n*** Cause (%d): %s";

                PKIX_CHECK(PKIX_PL_String_Create
                            (PKIX_ESCASCII,
                            format,
                            0,
                            &formatString,
                            plContext),
                            PKIX_STRINGCREATEFAILED);

                /* Create the optional Cause String */
                PKIX_CHECK(PKIX_PL_Sprintf
                            (&optCauseString,
                            plContext,
                            formatString,
                            pkix_error_cause_depth,
                            causeString),
                            PKIX_SPRINTFFAILED);

                PKIX_DECREF(formatString);

                pkix_error_cause_depth--;
        }

        /* Create the Format String */
        if (optCauseString != NULL) {
                format = "*** %s Error- %s%s";
        } else {
                format = "*** %s Error- %s";
        }

        /* Ensure that error errClass is known, otherwise default to Object */
        if (errClass >= PKIX_NUMERRORCLASSES) {
                errClass = 0;
        }

        PKIX_CHECK(PKIX_PL_String_Create
                    (PKIX_ESCASCII,
                    (void *)PKIX_ERRORCLASSNAMES[errClass],
                    0,
                    &errorNameString,
                    plContext),
                    PKIX_STRINGCREATEFAILED);

        PKIX_CHECK(PKIX_PL_String_Create
                    (PKIX_ESCASCII,
                    format,
                    0,
                    &formatString,
                    plContext),
                    PKIX_STRINGCREATEFAILED);

        /* Create the output String */
        PKIX_CHECK(PKIX_PL_Sprintf
                    (pString,
                    plContext,
                    formatString,
                    errorNameString,
                    desc,
                    optCauseString),
                    PKIX_SPRINTFFAILED);

cleanup:

        PKIX_DECREF(desc);
        PKIX_DECREF(causeString);
        PKIX_DECREF(formatString);
        PKIX_DECREF(optCauseString);
        PKIX_DECREF(errorNameString);

        PKIX_RETURN(ERROR);
}

/*
 * FUNCTION: pkix_Error_Hashcode
 * (see comments for PKIX_PL_HashcodeCallback in pkix_pl_system.h)
 */
static PKIX_Error *
pkix_Error_Hashcode(
        PKIX_PL_Object *object,
        PKIX_UInt32 *pResult,
        void *plContext)
{
        PKIX_ENTER(ERROR, "pkix_Error_Hashcode");
        PKIX_NULLCHECK_TWO(object, pResult);

        /* XXX Unimplemented */
        /* XXX Need to make hashcodes equal when two errors are equal */
        *pResult = (PKIX_UInt32)((char *)object - (char *)NULL);

        PKIX_RETURN(ERROR);
}

/* --Initializers------------------------------------------------- */

/*
 * PKIX_ERRORCLASSNAMES is an array of strings, with each string holding a
 * descriptive name for an error errClass. This is used by the default
 * PKIX_PL_Error_ToString function.
 *
 * Note: PKIX_ERRORCLASSES is defined in pkixt.h as a list of error types.
 * (More precisely, as a list of invocations of ERRMACRO(type).) The
 * macro is expanded in pkixt.h to define error numbers, and here to
 * provide corresponding strings. For example, since the fifth ERRMACRO
 * entry is MUTEX, then PKIX_MUTEX_ERROR is defined in pkixt.h as 4, and
 * PKIX_ERRORCLASSNAMES[4] is initialized here with the value "MUTEX".
 */
#undef ERRMACRO
#define ERRMACRO(type) #type

const char *
PKIX_ERRORCLASSNAMES[PKIX_NUMERRORCLASSES] =
{
    PKIX_ERRORCLASSES
};

/*
 * FUNCTION: pkix_Error_RegisterSelf
 * DESCRIPTION:
 *  Registers PKIX_ERROR_TYPE and its related functions with systemClasses[]
 * THREAD SAFETY:
 *  Not Thread Safe - for performance and complexity reasons
 *
 *  Since this function is only called by PKIX_PL_Initialize, which should
 *  only be called once, it is acceptable that this function is not
 *  thread-safe.
 */
PKIX_Error *
pkix_Error_RegisterSelf(void *plContext)
{
        extern pkix_ClassTable_Entry systemClasses[PKIX_NUMTYPES];
        pkix_ClassTable_Entry entry;

        PKIX_ENTER(ERROR, "pkix_Error_RegisterSelf");

        entry.description = "Error";
        entry.objCounter = 0;
        entry.typeObjectSize = sizeof(PKIX_Error);
        entry.destructor = pkix_Error_Destroy;
        entry.equalsFunction = pkix_Error_Equals;
        entry.hashcodeFunction = pkix_Error_Hashcode;
        entry.toStringFunction = pkix_Error_ToString;
        entry.comparator = NULL;
        entry.duplicateFunction = pkix_duplicateImmutable;

        systemClasses[PKIX_ERROR_TYPE] = entry;

        PKIX_RETURN(ERROR);
}

/* --Public-Functions--------------------------------------------- */

/*
 * FUNCTION: PKIX_Error_Create (see comments in pkix_util.h)
 */
PKIX_Error *
PKIX_Error_Create(
        PKIX_ERRORCLASS errClass,
        PKIX_Error *cause,
        PKIX_PL_Object *info,
        PKIX_ERRORCODE errCode,
        PKIX_Error **pError,
        void *plContext)
{
        PKIX_Error *tempCause = NULL;
        PKIX_Error *error = NULL;

        PKIX_ENTER(ERROR, "PKIX_Error_Create");

        PKIX_NULLCHECK_ONE(pError);

        /*
         * when called here, if PKIX_PL_Object_Alloc returns an error,
         * it must be a PKIX_ALLOC_ERROR
         */
        pkixErrorResult = PKIX_PL_Object_Alloc
                (PKIX_ERROR_TYPE,
                ((PKIX_UInt32)(sizeof (PKIX_Error))),
                (PKIX_PL_Object **)&error,
                plContext);

        if (pkixErrorResult) return (pkixErrorResult);

        error->errClass = errClass;

        /* Ensure we don't have a loop. Follow causes until NULL */
        for (tempCause = cause;
            tempCause != NULL;
            tempCause = tempCause->cause) {
                /* If we detect a loop, throw a new error */
                if (tempCause == error) {
                        PKIX_ERROR(PKIX_LOOPOFERRORCAUSEDETECTED);
                }
        }

        PKIX_INCREF(cause);
        error->cause = cause;

        PKIX_INCREF(info);
        error->info = info;

        error->errCode = errCode;

        error->plErr = PKIX_PLErrorIndex[error->errCode];

        *pError = error;
        error = NULL;

cleanup:
        /* PKIX-XXX Fix for leak during error creation */
        PKIX_DECREF(error);

        PKIX_RETURN(ERROR);
}

/*
 * FUNCTION: PKIX_Error_GetErrorClass (see comments in pkix_util.h)
 */
PKIX_Error *
PKIX_Error_GetErrorClass(
        PKIX_Error *error,
        PKIX_ERRORCLASS *pClass,
        void *plContext)
{
        PKIX_ENTER(ERROR, "PKIX_Error_GetErrorClass");
        PKIX_NULLCHECK_TWO(error, pClass);

        *pClass = error->errClass;

        PKIX_RETURN(ERROR);
}

/*
 * FUNCTION: PKIX_Error_GetErrorCode (see comments in pkix_util.h)
 */
PKIX_Error *
PKIX_Error_GetErrorCode(
        PKIX_Error *error,
        PKIX_ERRORCODE *pCode,
        void *plContext)
{
        PKIX_ENTER(ERROR, "PKIX_Error_GetErrorCode");
        PKIX_NULLCHECK_TWO(error, pCode);

        *pCode = error->errCode;

        PKIX_RETURN(ERROR);
}

/*
 * FUNCTION: PKIX_Error_GetCause (see comments in pkix_util.h)
 */
PKIX_Error *
PKIX_Error_GetCause(
        PKIX_Error *error,
        PKIX_Error **pCause,
        void *plContext)
{
        PKIX_ENTER(ERROR, "PKIX_Error_GetCause");
        PKIX_NULLCHECK_TWO(error, pCause);

        if (error->cause != PKIX_ALLOC_ERROR()){
                PKIX_INCREF(error->cause);
        }

        *pCause = error->cause;

cleanup:
        PKIX_RETURN(ERROR);
}

/*
 * FUNCTION: PKIX_Error_GetSupplementaryInfo (see comments in pkix_util.h)
 */
PKIX_Error *
PKIX_Error_GetSupplementaryInfo(
        PKIX_Error *error,
        PKIX_PL_Object **pInfo,
        void *plContext)
{
        PKIX_ENTER(ERROR, "PKIX_Error_GetSupplementaryInfo");
        PKIX_NULLCHECK_TWO(error, pInfo);

        PKIX_INCREF(error->info);

        *pInfo = error->info;

cleanup:
        PKIX_RETURN(ERROR);
}

/*
 * FUNCTION: PKIX_Error_GetDescription (see comments in pkix_util.h)
 */
PKIX_Error *
PKIX_Error_GetDescription(
        PKIX_Error *error,
        PKIX_PL_String **pDesc,
        void *plContext)
{
        PKIX_PL_String *descString = NULL;
#ifndef PKIX_ERROR_DESCRIPTION
        char errorStr[32];
#endif

        PKIX_ENTER(ERROR, "PKIX_Error_GetDescription");
        PKIX_NULLCHECK_TWO(error, pDesc);

#ifndef PKIX_ERROR_DESCRIPTION
        PR_snprintf(errorStr, 32, "Error code: %d", error->errCode);
#endif

        PKIX_PL_String_Create(PKIX_ESCASCII,
#if defined PKIX_ERROR_DESCRIPTION
                              (void *)PKIX_ErrorText[error->errCode],
#else
                              errorStr,
#endif
                              0,
                              &descString,
                              plContext);

        *pDesc = descString;

        PKIX_RETURN(ERROR);
}