michael@0: /*
michael@0: ******************************************************************************
michael@0: *
michael@0: *   Copyright (C) 1999-2011, International Business Machines
michael@0: *   Corporation and others.  All Rights Reserved.
michael@0: *
michael@0: ******************************************************************************/
michael@0: 
michael@0: 
michael@0: /*----------------------------------------------------------------------------------
michael@0:  *
michael@0:  *  UDataMemory     A class-like struct that serves as a handle to a piece of memory
michael@0:  *                  that contains some ICU data (resource, converters, whatever.)
michael@0:  *
michael@0:  *                  When an application opens ICU data (with udata_open, for example,
michael@0:  *                  a UDataMemory * is returned.
michael@0:  *
michael@0:  *----------------------------------------------------------------------------------*/
michael@0: 
michael@0: #include "unicode/utypes.h"
michael@0: #include "cmemory.h"
michael@0: #include "unicode/udata.h"
michael@0: 
michael@0: #include "udatamem.h"
michael@0: 
michael@0: U_CFUNC void UDataMemory_init(UDataMemory *This) {
michael@0:     uprv_memset(This, 0, sizeof(UDataMemory));
michael@0:     This->length=-1;
michael@0: }
michael@0: 
michael@0: 
michael@0: U_CFUNC void UDatamemory_assign(UDataMemory *dest, UDataMemory *source) {
michael@0:     /* UDataMemory Assignment.  Destination UDataMemory must be initialized first.  */
michael@0:     UBool mallocedFlag = dest->heapAllocated;
michael@0:     uprv_memcpy(dest, source, sizeof(UDataMemory));
michael@0:     dest->heapAllocated = mallocedFlag;
michael@0: }
michael@0: 
michael@0: U_CFUNC UDataMemory *UDataMemory_createNewInstance(UErrorCode *pErr) {
michael@0:     UDataMemory *This;
michael@0: 
michael@0:     if (U_FAILURE(*pErr)) {
michael@0:         return NULL;
michael@0:     }
michael@0:     This = uprv_malloc(sizeof(UDataMemory));
michael@0:     if (This == NULL) {
michael@0:         *pErr = U_MEMORY_ALLOCATION_ERROR; }
michael@0:     else {
michael@0:         UDataMemory_init(This);
michael@0:         This->heapAllocated = TRUE;
michael@0:     }
michael@0:     return This;
michael@0: }
michael@0: 
michael@0: 
michael@0: U_CFUNC const DataHeader *
michael@0: UDataMemory_normalizeDataPointer(const void *p) {
michael@0:     /* allow the data to be optionally prepended with an alignment-forcing double value */
michael@0:     const DataHeader *pdh = (const DataHeader *)p;
michael@0:     if(pdh==NULL || (pdh->dataHeader.magic1==0xda && pdh->dataHeader.magic2==0x27)) {
michael@0:         return pdh;
michael@0:     } else {
michael@0: #if U_PLATFORM == U_PF_OS400
michael@0:         /*
michael@0:         TODO: Fix this once the compiler implements this feature. Keep in sync with genccode.c
michael@0: 
michael@0:         This is here because this platform can't currently put
michael@0:         const data into the read-only pages of an object or
michael@0:         shared library (service program). Only strings are allowed in read-only
michael@0:         pages, so we use char * strings to store the data.
michael@0: 
michael@0:         In order to prevent the beginning of the data from ever matching the
michael@0:         magic numbers we must skip the initial double.
michael@0:         [grhoten 4/24/2003]
michael@0:         */
michael@0:         return (const DataHeader *)*((const void **)p+1);
michael@0: #else
michael@0:         return (const DataHeader *)((const double *)p+1);
michael@0: #endif
michael@0:     }
michael@0: }
michael@0: 
michael@0: 
michael@0: U_CFUNC void UDataMemory_setData (UDataMemory *This, const void *dataAddr) {
michael@0:     This->pHeader = UDataMemory_normalizeDataPointer(dataAddr);
michael@0: }
michael@0: 
michael@0: 
michael@0: U_CAPI void U_EXPORT2
michael@0: udata_close(UDataMemory *pData) {
michael@0:     if(pData!=NULL) {
michael@0:         uprv_unmapFile(pData);
michael@0:         if(pData->heapAllocated ) {
michael@0:             uprv_free(pData);
michael@0:         } else {
michael@0:             UDataMemory_init(pData);
michael@0:         }
michael@0:     }
michael@0: }
michael@0: 
michael@0: U_CAPI const void * U_EXPORT2
michael@0: udata_getMemory(UDataMemory *pData) {
michael@0:     if(pData!=NULL && pData->pHeader!=NULL) {
michael@0:         return (char *)(pData->pHeader)+udata_getHeaderSize(pData->pHeader);
michael@0:     } else {
michael@0:         return NULL;
michael@0:     }
michael@0: }
michael@0: 
michael@0: /**
michael@0:  * Get the length of the data item if possible.
michael@0:  * The length may be up to 15 bytes larger than the actual data.
michael@0:  *
michael@0:  * TODO Consider making this function public.
michael@0:  * It would have to return the actual length in more cases.
michael@0:  * For example, the length of the last item in a .dat package could be
michael@0:  * computed from the size of the whole .dat package minus the offset of the
michael@0:  * last item.
michael@0:  * The size of a file that was directly memory-mapped could be determined
michael@0:  * using some system API.
michael@0:  *
michael@0:  * In order to get perfect values for all data items, we may have to add a
michael@0:  * length field to UDataInfo, but that complicates data generation
michael@0:  * and may be overkill.
michael@0:  *
michael@0:  * @param pData The data item.
michael@0:  * @return the length of the data item, or -1 if not known
michael@0:  * @internal Currently used only in cintltst/udatatst.c
michael@0:  */
michael@0: U_CAPI int32_t U_EXPORT2
michael@0: udata_getLength(const UDataMemory *pData) {
michael@0:     if(pData!=NULL && pData->pHeader!=NULL && pData->length>=0) {
michael@0:         /*
michael@0:          * subtract the header size,
michael@0:          * return only the size of the actual data starting at udata_getMemory()
michael@0:          */
michael@0:         return pData->length-udata_getHeaderSize(pData->pHeader);
michael@0:     } else {
michael@0:         return -1;
michael@0:     }
michael@0: }
michael@0: 
michael@0: /**
michael@0:  * Get the memory including the data header.
michael@0:  * Used in cintltst/udatatst.c
michael@0:  * @internal
michael@0:  */
michael@0: U_CAPI const void * U_EXPORT2
michael@0: udata_getRawMemory(const UDataMemory *pData) {
michael@0:     if(pData!=NULL && pData->pHeader!=NULL) {
michael@0:         return pData->pHeader;
michael@0:     } else {
michael@0:         return NULL;
michael@0:     }
michael@0: }
michael@0: 
michael@0: U_CFUNC UBool UDataMemory_isLoaded(const UDataMemory *This) {
michael@0:     return This->pHeader != NULL;
michael@0: }