/*
******************************************************************************
*
* Copyright (C) 1999-2008, International Business Machines
* Corporation and others. All Rights Reserved.
*
******************************************************************************/
/*------------------------------------------------------------------------------
*
* UCommonData An abstract interface for dealing with ICU Common Data Files.
* ICU Common Data Files are a grouping of a number of individual
* data items (resources, converters, tables, anything) into a
* single file or dll. The combined format includes a table of
* contents for locating the individual items by name.
*
* Two formats for the table of contents are supported, which is
* why there is an abstract inteface involved.
*
*/
#include "unicode/utypes.h"
#include "unicode/udata.h"
#include "cstring.h"
#include "ucmndata.h"
#include "udatamem.h"
#if defined(UDATA_DEBUG) || defined(UDATA_DEBUG_DUMP)
# include <stdio.h>
#endif
U_CFUNC uint16_t
udata_getHeaderSize(const DataHeader *udh) {
if(udh==NULL) {
return 0;
} else if(udh->info.isBigEndian==U_IS_BIG_ENDIAN) {
/* same endianness */
return udh->dataHeader.headerSize;
} else {
/* opposite endianness */
uint16_t x=udh->dataHeader.headerSize;
return (uint16_t)((x<<8)|(x>>8));
}
}
U_CFUNC uint16_t
udata_getInfoSize(const UDataInfo *info) {
if(info==NULL) {
return 0;
} else if(info->isBigEndian==U_IS_BIG_ENDIAN) {
/* same endianness */
return info->size;
} else {
/* opposite endianness */
uint16_t x=info->size;
return (uint16_t)((x<<8)|(x>>8));
}
}
/*-----------------------------------------------------------------------------*
* *
* Pointer TOCs. TODO: This form of table-of-contents should be removed *
* because DLLs must be relocated on loading to correct the *
* pointer values and this operation makes shared memory *
* mapping of the data much less likely to work. *
* *
*-----------------------------------------------------------------------------*/
typedef struct {
const char *entryName;
const DataHeader *pHeader;
} PointerTOCEntry;
typedef struct {
uint32_t count;
uint32_t reserved;
PointerTOCEntry entry[2]; /* Actual size is from count. */
} PointerTOC;
/* definition of OffsetTOC struct types moved to ucmndata.h */
/*-----------------------------------------------------------------------------*
* *
* entry point lookup implementations *
* *
*-----------------------------------------------------------------------------*/
static uint32_t offsetTOCEntryCount(const UDataMemory *pData) {
int32_t retVal=0;
const UDataOffsetTOC *toc = (UDataOffsetTOC *)pData->toc;
if (toc != NULL) {
retVal = toc->count;
}
return retVal;
}
static const DataHeader *
offsetTOCLookupFn(const UDataMemory *pData,
const char *tocEntryName,
int32_t *pLength,
UErrorCode *pErrorCode) {
const UDataOffsetTOC *toc = (UDataOffsetTOC *)pData->toc;
if(toc!=NULL) {
const char *base=(const char *)toc;
uint32_t start, limit, number, lastNumber;
int32_t strResult;
const UDataOffsetTOCEntry *entry;
/* perform a binary search for the data in the common data's table of contents */
#if defined (UDATA_DEBUG_DUMP)
/* list the contents of the TOC each time .. not recommended */
for(start=0;start<toc->count;start++) {
fprintf(stderr, "\tx%d: %s\n", start, &base[toc->entry[start].nameOffset]);
}
#endif
start=0;
limit=toc->count; /* number of names in this table of contents */
lastNumber=limit;
entry=toc->entry;
for (;;) {
number = (start+limit)/2;
if (lastNumber == number) { /* Have we moved? */
break; /* We haven't moved, and it wasn't found; */
/* or the empty stub common data library was used during build. */
}
lastNumber = number;
strResult = uprv_strcmp(tocEntryName, base+entry[number].nameOffset);
if(strResult<0) {
limit=number;
} else if (strResult>0) {
start=number;
}
else {
/* found it */
#ifdef UDATA_DEBUG
fprintf(stderr, "%s: Found.\n", tocEntryName);
#endif
entry += number; /* Alias the entry to the current entry. */
if((number+1) < toc->count) {
*pLength = (int32_t)(entry[1].dataOffset - entry->dataOffset);
} else {
*pLength = -1;
}
return (const DataHeader *)(base+entry->dataOffset);
}
}
#ifdef UDATA_DEBUG
fprintf(stderr, "%s: Not found.\n", tocEntryName);
#endif
return NULL;
} else {
#ifdef UDATA_DEBUG
fprintf(stderr, "returning header\n");
#endif
return pData->pHeader;
}
}
static uint32_t pointerTOCEntryCount(const UDataMemory *pData) {
const PointerTOC *toc = (PointerTOC *)pData->toc;
return (uint32_t)((toc != NULL) ? (toc->count) : 0);
}
static const DataHeader *pointerTOCLookupFn(const UDataMemory *pData,
const char *name,
int32_t *pLength,
UErrorCode *pErrorCode) {
if(pData->toc!=NULL) {
const PointerTOC *toc = (PointerTOC *)pData->toc;
uint32_t start, limit, number, lastNumber;
int32_t strResult;
#if defined (UDATA_DEBUG_DUMP)
/* list the contents of the TOC each time .. not recommended */
for(start=0;start<toc->count;start++) {
fprintf(stderr, "\tx%d: %s\n", start, toc->entry[start].entryName);
}
#endif
/* perform a binary search for the data in the common data's table of contents */
start=0;
limit=toc->count;
lastNumber=limit;
for (;;) {
number = (start+limit)/2;
if (lastNumber == number) { /* Have we moved? */
break; /* We haven't moved, and it wasn't found, */
/* or the empty stub common data library was used during build. */
}
lastNumber = number;
strResult = uprv_strcmp(name, toc->entry[number].entryName);
if(strResult<0) {
limit=number;
} else if (strResult>0) {
start=number;
}
else {
/* found it */
#ifdef UDATA_DEBUG
fprintf(stderr, "%s: Found.\n", toc->entry[number].entryName);
#endif
*pLength=-1;
return UDataMemory_normalizeDataPointer(toc->entry[number].pHeader);
}
}
#ifdef UDATA_DEBUG
fprintf(stderr, "%s: Not found.\n", name);
#endif
return NULL;
} else {
return pData->pHeader;
}
}
static const commonDataFuncs CmnDFuncs = {offsetTOCLookupFn, offsetTOCEntryCount};
static const commonDataFuncs ToCPFuncs = {pointerTOCLookupFn, pointerTOCEntryCount};
/*----------------------------------------------------------------------*
* *
* checkCommonData Validate the format of a common data file. *
* Fill in the virtual function ptr based on TOC type *
* If the data is invalid, close the UDataMemory *
* and set the appropriate error code. *
* *
*----------------------------------------------------------------------*/
void udata_checkCommonData(UDataMemory *udm, UErrorCode *err) {
if (U_FAILURE(*err)) {
return;
}
if(!(udm->pHeader->dataHeader.magic1==0xda &&
udm->pHeader->dataHeader.magic2==0x27 &&
udm->pHeader->info.isBigEndian==U_IS_BIG_ENDIAN &&
udm->pHeader->info.charsetFamily==U_CHARSET_FAMILY)
) {
/* header not valid */
*err=U_INVALID_FORMAT_ERROR;
}
else if (udm->pHeader->info.dataFormat[0]==0x43 &&
udm->pHeader->info.dataFormat[1]==0x6d &&
udm->pHeader->info.dataFormat[2]==0x6e &&
udm->pHeader->info.dataFormat[3]==0x44 &&
udm->pHeader->info.formatVersion[0]==1
) {
/* dataFormat="CmnD" */
udm->vFuncs = &CmnDFuncs;
udm->toc=(const char *)udm->pHeader+udata_getHeaderSize(udm->pHeader);
}
else if(udm->pHeader->info.dataFormat[0]==0x54 &&
udm->pHeader->info.dataFormat[1]==0x6f &&
udm->pHeader->info.dataFormat[2]==0x43 &&
udm->pHeader->info.dataFormat[3]==0x50 &&
udm->pHeader->info.formatVersion[0]==1
) {
/* dataFormat="ToCP" */
udm->vFuncs = &ToCPFuncs;
udm->toc=(const char *)udm->pHeader+udata_getHeaderSize(udm->pHeader);
}
else {
/* dataFormat not recognized */
*err=U_INVALID_FORMAT_ERROR;
}
if (U_FAILURE(*err)) {
/* If the data is no good and we memory-mapped it ourselves,
* close the memory mapping so it doesn't leak. Note that this has
* no effect on non-memory mapped data, other than clearing fields in udm.
*/
udata_close(udm);
}
}
/*
* TODO: Add a udata_swapPackageHeader() function that swaps an ICU .dat package
* header but not its sub-items.
* This function will be needed for automatic runtime swapping.
* Sub-items should not be swapped to limit the swapping to the parts of the
* package that are actually used.
*
* Since lengths of items are implicit in the order and offsets of their
* ToC entries, and since offsets are relative to the start of the ToC,
* a swapped version may need to generate a different data structure
* with pointers to the original data items and with their lengths
* (-1 for the last one if it is not known), and maybe even pointers to the
* swapped versions of the items.
* These pointers to swapped versions would establish a cache;
* instead, each open data item could simply own the storage for its swapped
* data. This fits better with the current design.
*
* markus 2003sep18 Jitterbug 2235
*/