// // file: rbbistbl.cpp Implementation of the ICU RBBISymbolTable class // /* *************************************************************************** * Copyright (C) 2002-2003 International Business Machines Corporation * * and others. All rights reserved. * *************************************************************************** */ #include "unicode/utypes.h" #if !UCONFIG_NO_BREAK_ITERATION #include "unicode/unistr.h" #include "unicode/uniset.h" #include "unicode/uchar.h" #include "unicode/parsepos.h" #include "umutex.h" #include "rbbirb.h" #include "rbbinode.h" // // RBBISymbolTableEntry_deleter Used by the UHashTable to delete the contents // when the hash table is deleted. // U_CDECL_BEGIN static void U_EXPORT2 U_CALLCONV RBBISymbolTableEntry_deleter(void *p) { RBBISymbolTableEntry *px = (RBBISymbolTableEntry *)p; delete px; } U_CDECL_END U_NAMESPACE_BEGIN RBBISymbolTable::RBBISymbolTable(RBBIRuleScanner *rs, const UnicodeString &rules, UErrorCode &status) :fRules(rules), fRuleScanner(rs), ffffString(UChar(0xffff)) { fHashTable = NULL; fCachedSetLookup = NULL; fHashTable = uhash_open(uhash_hashUnicodeString, uhash_compareUnicodeString, &status); // uhash_open checks status if (U_FAILURE(status)) { return; } uhash_setValueDeleter(fHashTable, RBBISymbolTableEntry_deleter); } RBBISymbolTable::~RBBISymbolTable() { uhash_close(fHashTable); } // // RBBISymbolTable::lookup This function from the abstract symbol table inteface // looks up a variable name and returns a UnicodeString // containing the substitution text. // // The variable name does NOT include the leading $. // const UnicodeString *RBBISymbolTable::lookup(const UnicodeString& s) const { RBBISymbolTableEntry *el; RBBINode *varRefNode; RBBINode *exprNode; RBBINode *usetNode; const UnicodeString *retString; RBBISymbolTable *This = (RBBISymbolTable *)this; // cast off const el = (RBBISymbolTableEntry *)uhash_get(fHashTable, &s); if (el == NULL) { return NULL; } varRefNode = el->val; exprNode = varRefNode->fLeftChild; // Root node of expression for variable if (exprNode->fType == RBBINode::setRef) { // The $variable refers to a single UnicodeSet // return the ffffString, which will subsequently be interpreted as a // stand-in character for the set by RBBISymbolTable::lookupMatcher() usetNode = exprNode->fLeftChild; This->fCachedSetLookup = usetNode->fInputSet; retString = &ffffString; } else { // The variable refers to something other than just a set. // return the original source string for the expression retString = &exprNode->fText; This->fCachedSetLookup = NULL; } return retString; } // // RBBISymbolTable::lookupMatcher This function from the abstract symbol table // interface maps a single stand-in character to a // pointer to a Unicode Set. The Unicode Set code uses this // mechanism to get all references to the same $variable // name to refer to a single common Unicode Set instance. // // This implementation cheats a little, and does not maintain a map of stand-in chars // to sets. Instead, it takes advantage of the fact that the UnicodeSet // constructor will always call this function right after calling lookup(), // and we just need to remember what set to return between these two calls. const UnicodeFunctor *RBBISymbolTable::lookupMatcher(UChar32 ch) const { UnicodeSet *retVal = NULL; RBBISymbolTable *This = (RBBISymbolTable *)this; // cast off const if (ch == 0xffff) { retVal = fCachedSetLookup; This->fCachedSetLookup = 0; } return retVal; } // // RBBISymbolTable::parseReference This function from the abstract symbol table interface // looks for a $variable name in the source text. // It does not look it up, only scans for it. // It is used by the UnicodeSet parser. // // This implementation is lifted pretty much verbatim // from the rules based transliterator implementation. // I didn't see an obvious way of sharing it. // UnicodeString RBBISymbolTable::parseReference(const UnicodeString& text, ParsePosition& pos, int32_t limit) const { int32_t start = pos.getIndex(); int32_t i = start; UnicodeString result; while (i < limit) { UChar c = text.charAt(i); if ((i==start && !u_isIDStart(c)) || !u_isIDPart(c)) { break; } ++i; } if (i == start) { // No valid name chars return result; // Indicate failure with empty string } pos.setIndex(i); text.extractBetween(start, i, result); return result; } // // RBBISymbolTable::lookupNode Given a key (a variable name), return the // corresponding RBBI Node. If there is no entry // in the table for this name, return NULL. // RBBINode *RBBISymbolTable::lookupNode(const UnicodeString &key) const{ RBBINode *retNode = NULL; RBBISymbolTableEntry *el; el = (RBBISymbolTableEntry *)uhash_get(fHashTable, &key); if (el != NULL) { retNode = el->val; } return retNode; } // // RBBISymbolTable::addEntry Add a new entry to the symbol table. // Indicate an error if the name already exists - // this will only occur in the case of duplicate // variable assignments. // void RBBISymbolTable::addEntry (const UnicodeString &key, RBBINode *val, UErrorCode &err) { RBBISymbolTableEntry *e; /* test for buffer overflows */ if (U_FAILURE(err)) { return; } e = (RBBISymbolTableEntry *)uhash_get(fHashTable, &key); if (e != NULL) { err = U_BRK_VARIABLE_REDFINITION; return; } e = new RBBISymbolTableEntry; if (e == NULL) { err = U_MEMORY_ALLOCATION_ERROR; return; } e->key = key; e->val = val; uhash_put( fHashTable, &e->key, e, &err); } RBBISymbolTableEntry::RBBISymbolTableEntry() : UMemory(), key(), val(NULL) {} RBBISymbolTableEntry::~RBBISymbolTableEntry() { // The "val" of a symbol table entry is a variable reference node. // The l. child of the val is the rhs expression from the assignment. // Unlike other node types, children of variable reference nodes are not // automatically recursively deleted. We do it manually here. delete val->fLeftChild; val->fLeftChild = NULL; delete val; // Note: the key UnicodeString is destructed by virtue of being in the object by value. } // // RBBISymbolTable::print Debugging function, dump out the symbol table contents. // void RBBISymbolTable::print() const { RBBIDebugPrintf("Variable Definitions\n" "Name Node Val String Val\n" "----------------------------------------------------------------------\n"); int32_t pos = -1; const UHashElement *e = NULL; for (;;) { e = uhash_nextElement(fHashTable, &pos); if (e == NULL ) { break; } RBBISymbolTableEntry *s = (RBBISymbolTableEntry *)e->value.pointer; RBBINode::printUnicodeString(s->key, 15); RBBIDebugPrintf(" %8p ", (void *)s->val); RBBINode::printUnicodeString(s->val->fLeftChild->fText); RBBIDebugPrintf("\n"); } RBBIDebugPrintf("\nParsed Variable Definitions\n"); pos = -1; for (;;) { e = uhash_nextElement(fHashTable, &pos); if (e == NULL ) { break; } RBBISymbolTableEntry *s = (RBBISymbolTableEntry *)e->value.pointer; RBBINode::printUnicodeString(s->key); s->val->fLeftChild->printTree(); RBBIDebugPrintf("\n"); } } U_NAMESPACE_END #endif /* #if !UCONFIG_NO_BREAK_ITERATION */