scuffed-code/icu4c/source/i18n/brkdict.cpp

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/*
**********************************************************************
* Copyright (C) 1999-2000 IBM and others. All rights reserved.
**********************************************************************
* Date Name Description
* 12/1/99 rtg Ported from Java
* 01/13/2000 helena Added UErrorCode to ctors.
**********************************************************************
*/
#include "brkdict.h"
#include "cmemory.h"
#include "unicode/resbund.h"
//=================================================================================
// deserialization
//=================================================================================
BreakDictionary::BreakDictionary(char* dictionaryFilename, UErrorCode& status)
{
if (U_FAILURE(status)) return;
ResourceBundle th((char *)0, Locale("th"), status);
if (U_FAILURE(status)) return;
ResourceBundle th_dict = th.get("BreakDictionaryData", status);
if (U_FAILURE(status)) return;
int32_t len;
const uint8_t * data = th_dict.getBinary(len, status);
if (U_FAILURE(status)) return;
UMemoryStream* dictionaryStream = uprv_mstrm_openBuffer(data, len);
if (dictionaryStream == 0) {
status = U_FILE_ACCESS_ERROR;
return;
}
readDictionaryFile(dictionaryStream);
uprv_mstrm_close(dictionaryStream);
}
BreakDictionary::~BreakDictionary()
{
ucmp8_close(columnMap);
delete [] table;
delete [] rowIndex;
delete [] rowIndexFlags;
delete [] rowIndexFlagsIndex;
delete [] rowIndexShifts;
}
// macros to support readDictionaryFile. The data files originated from a Java
// program, and Java always writes data out in big-endian format. These macros will
// byte-swap the data for appropriate use on Windows.
#if U_IS_BIG_ENDIAN
#define SWAP32(x)
#define SWAP16(x)
#else
#define SWAP32(x) x = (x >> 24 & 0xff) | (x >> 8 & 0xff00) | (x << 8 & 0xff0000) | (x << 24 & 0xff000000)
#define SWAP16(x) x = (x << 8 & 0xff00) | (x >> 8 & 0xff)
#endif
void
BreakDictionary::readDictionaryFile(UMemoryStream* in)
{
int32_t l;
int32_t version;
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int i;
// read in the version number (right now we just ignore it)
uprv_mstrm_read(in, &version, 4);
// read in the column map (this is serialized in its internal form:
// an index array followed by a data array)
uprv_mstrm_read(in, &l, 4);
SWAP32(l);
uint16_t* temp = (uint16_t*) uprv_malloc(sizeof(uint16_t)*l);
uprv_mstrm_read(in, temp, l * sizeof (int16_t) );
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for (i = 0; i < l; i++) {
SWAP16(temp[i]);
}
uprv_mstrm_read(in, &l, 4);
SWAP32(l);
int8_t* temp2 = (int8_t*) uprv_malloc(sizeof(int8_t)*l);
uprv_mstrm_read(in, temp2, l);
columnMap = ucmp8_openAdopt(temp, temp2, l);
// read in numCols and numColGroups
uprv_mstrm_read(in, &numCols, 4);
SWAP32(numCols);
uprv_mstrm_read(in, &numColGroups, 4);
SWAP32(numColGroups);
// read in the row-number index
uprv_mstrm_read(in, &l, 4);
SWAP32(l);
rowIndex = new int16_t[l];
uprv_mstrm_read(in, rowIndex, l * sizeof (int16_t) );
for (i = 0; i < l; i++) {
SWAP16(rowIndex[i]);
}
// load in the populated-cells bitmap: index first, then bitmap list
uprv_mstrm_read(in, &l, 4);
SWAP32(l);
rowIndexFlagsIndex = new int16_t[l];
uprv_mstrm_read(in, rowIndexFlagsIndex, l * sizeof(int16_t) );
for (i = 0; i < l; i++) {
SWAP16(rowIndexFlagsIndex[i]);
}
uprv_mstrm_read(in, &l, 4);
SWAP32(l);
rowIndexFlags = new int32_t[l];
uprv_mstrm_read(in, rowIndexFlags, l * sizeof(int32_t));
for (i = 0; i < l; i++) {
SWAP32(rowIndexFlags[i]);
}
// load in the row-shift index
uprv_mstrm_read(in, &l, 4);
SWAP32(l);
rowIndexShifts = new int8_t[l];
uprv_mstrm_read(in, rowIndexShifts, l);
// finally, load in the actual state table
uprv_mstrm_read(in, &l, 4);
SWAP32(l);
table = new int16_t[l];
uprv_mstrm_read(in, table, l * sizeof(int16_t) );
for (i = 0; i < l; i++) {
SWAP16(table[i]);
}
// the reverse column map occurs next in the file. In the C/C++ code, for the
// time being, we're not going to worry about that.
}
//=================================================================================
// access to the words
//=================================================================================
/**
* Uses the column map to map the character to a column number, then
* passes the row and column number to the other version of at()
* @param row The current state
* @param ch The character whose column we're interested in
* @return The new state to transition to
*/
int16_t
BreakDictionary::at(int32_t row, UChar ch) const
{
int16_t col = ucmp8_get(columnMap, ch);
return at(row, (int32_t)col);
}
/**
* Returns the value in the cell with the specified (logical) row and
* column numbers. In DictionaryBasedBreakIterator, the row number is
* a state number, the column number is an input, and the return value
* is the row number of the new state to transition to. (0 is the
* "error" state, and -1 is the "end of word" state in a dictionary)
* @param row The row number of the current state
* @param col The column number of the input character (0 means "not a
* dictionary character")
* @return The row number of the new state to transition to
*/
int16_t
BreakDictionary::at(int32_t row, int32_t col) const
{
if (cellIsPopulated(row, col)) {
// we map from logical to physical row number by looking up the
// mapping in rowIndex; we map from logical column number to
// physical column number by looking up a shift value for this
// logical row and offsetting the logical column number by
// the shift amount. Then we can use internalAt() to actually
// get the value out of the table.
return internalAt(rowIndex[row], col + rowIndexShifts[row]);
}
else {
return 0;
}
}
//=================================================================================
// implementation
//=================================================================================
/**
* Given (logical) row and column numbers, returns true if the
* cell in that position is populated
*/
UBool
BreakDictionary::cellIsPopulated(int32_t row, int32_t col) const
{
// look up the entry in the bitmap index for the specified row.
// If it's a negative number, it's the column number of the only
// populated cell in the row
if (rowIndexFlagsIndex[row] < 0) {
return col == -rowIndexFlagsIndex[row];
}
// if it's a positive number, it's the offset of an entry in the bitmap
// list. If the table is more than 32 columns wide, the bitmap is stored
// successive entries in the bitmap list, so we have to divide the column
// number by 32 and offset the number we got out of the index by the result.
// Once we have the appropriate piece of the bitmap, test the appropriate
// bit and return the result.
else {
int32_t flags = rowIndexFlags[rowIndexFlagsIndex[row] + (col >> 5)];
return (flags & (1 << (col & 0x1f))) != 0;
}
}
/**
* Implementation of at() when we know the specified cell is populated.
* @param row The PHYSICAL row number of the cell
* @param col The PHYSICAL column number of the cell
* @return The value stored in the cell
*/
int16_t
BreakDictionary::internalAt(int32_t row, int32_t col) const
{
// the table is a one-dimensional array, so this just does the math necessary
// to treat it as a two-dimensional array (we don't just use a two-dimensional
// array because two-dimensional arrays are inefficient in Java)
return table[row * numCols + col];
}