godot/thirdparty/icu4c/common/udatamem.cpp

162 lines
4.9 KiB
C++

// © 2016 and later: Unicode, Inc. and others.
// License & terms of use: http://www.unicode.org/copyright.html
/*
******************************************************************************
*
* Copyright (C) 1999-2011, International Business Machines
* Corporation and others. All Rights Reserved.
*
******************************************************************************/
/*----------------------------------------------------------------------------------
*
* UDataMemory A class-like struct that serves as a handle to a piece of memory
* that contains some ICU data (resource, converters, whatever.)
*
* When an application opens ICU data (with udata_open, for example,
* a UDataMemory * is returned.
*
*----------------------------------------------------------------------------------*/
#include "unicode/utypes.h"
#include "cmemory.h"
#include "unicode/udata.h"
#include "udatamem.h"
U_CFUNC void UDataMemory_init(UDataMemory *This) {
uprv_memset(This, 0, sizeof(UDataMemory));
This->length=-1;
}
U_CFUNC void UDatamemory_assign(UDataMemory *dest, UDataMemory *source) {
/* UDataMemory Assignment. Destination UDataMemory must be initialized first. */
UBool mallocedFlag = dest->heapAllocated;
uprv_memcpy(dest, source, sizeof(UDataMemory));
dest->heapAllocated = mallocedFlag;
}
U_CFUNC UDataMemory *UDataMemory_createNewInstance(UErrorCode *pErr) {
UDataMemory *This;
if (U_FAILURE(*pErr)) {
return NULL;
}
This = (UDataMemory *)uprv_malloc(sizeof(UDataMemory));
if (This == NULL) {
*pErr = U_MEMORY_ALLOCATION_ERROR; }
else {
UDataMemory_init(This);
This->heapAllocated = TRUE;
}
return This;
}
U_CFUNC const DataHeader *
UDataMemory_normalizeDataPointer(const void *p) {
/* allow the data to be optionally prepended with an alignment-forcing double value */
const DataHeader *pdh = (const DataHeader *)p;
if(pdh==NULL || (pdh->dataHeader.magic1==0xda && pdh->dataHeader.magic2==0x27)) {
return pdh;
} else {
#if U_PLATFORM == U_PF_OS400
/*
TODO: Fix this once the compiler implements this feature. Keep in sync with genccode.c
This is here because this platform can't currently put
const data into the read-only pages of an object or
shared library (service program). Only strings are allowed in read-only
pages, so we use char * strings to store the data.
In order to prevent the beginning of the data from ever matching the
magic numbers we must skip the initial double.
[grhoten 4/24/2003]
*/
return (const DataHeader *)*((const void **)p+1);
#else
return (const DataHeader *)((const double *)p+1);
#endif
}
}
U_CFUNC void UDataMemory_setData (UDataMemory *This, const void *dataAddr) {
This->pHeader = UDataMemory_normalizeDataPointer(dataAddr);
}
U_CAPI void U_EXPORT2
udata_close(UDataMemory *pData) {
if(pData!=NULL) {
uprv_unmapFile(pData);
if(pData->heapAllocated ) {
uprv_free(pData);
} else {
UDataMemory_init(pData);
}
}
}
U_CAPI const void * U_EXPORT2
udata_getMemory(UDataMemory *pData) {
if(pData!=NULL && pData->pHeader!=NULL) {
return (char *)(pData->pHeader)+udata_getHeaderSize(pData->pHeader);
} else {
return NULL;
}
}
/**
* Get the length of the data item if possible.
* The length may be up to 15 bytes larger than the actual data.
*
* TODO Consider making this function public.
* It would have to return the actual length in more cases.
* For example, the length of the last item in a .dat package could be
* computed from the size of the whole .dat package minus the offset of the
* last item.
* The size of a file that was directly memory-mapped could be determined
* using some system API.
*
* In order to get perfect values for all data items, we may have to add a
* length field to UDataInfo, but that complicates data generation
* and may be overkill.
*
* @param pData The data item.
* @return the length of the data item, or -1 if not known
* @internal Currently used only in cintltst/udatatst.c
*/
U_CAPI int32_t U_EXPORT2
udata_getLength(const UDataMemory *pData) {
if(pData!=NULL && pData->pHeader!=NULL && pData->length>=0) {
/*
* subtract the header size,
* return only the size of the actual data starting at udata_getMemory()
*/
return pData->length-udata_getHeaderSize(pData->pHeader);
} else {
return -1;
}
}
/**
* Get the memory including the data header.
* Used in cintltst/udatatst.c
* @internal
*/
U_CAPI const void * U_EXPORT2
udata_getRawMemory(const UDataMemory *pData) {
if(pData!=NULL && pData->pHeader!=NULL) {
return pData->pHeader;
} else {
return NULL;
}
}
U_CFUNC UBool UDataMemory_isLoaded(const UDataMemory *This) {
return This->pHeader != NULL;
}