Check in the pristine copy of ICU 4.6...

icu46/source/common/rbbistbl.cpp

+//
+//  file:  rbbistbl.cpp    Implementation of the ICU RBBISymbolTable class
+//
+/*
+***************************************************************************
+*   Copyright (C) 2002-2006 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_CALLCONV RBBISymbolTableEntry_deleter(void *p) {
+    U_NAMESPACE_QUALIFIER RBBISymbolTableEntry *px = (U_NAMESPACE_QUALIFIER 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, NULL, &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.
+//
+#ifdef RBBI_DEBUG
+void RBBISymbolTable::rbbiSymtablePrint() 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;
+
+        RBBI_DEBUG_printUnicodeString(s->key, 15);
+        RBBIDebugPrintf("   %8p   ", (void *)s->val);
+        RBBI_DEBUG_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;
+        RBBI_DEBUG_printUnicodeString(s->key);
+        s->val->fLeftChild->printTree(TRUE);
+        RBBIDebugPrintf("\n");
+    }
+}
+#endif
+
+
+
+
+
+U_NAMESPACE_END
+
+#endif /* #if !UCONFIG_NO_BREAK_ITERATION */