ExpressionCompoundVariable.cpp

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/* Copyright (c) 2005-2009 Rexx Language Association. All rights reserved.    */
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/*----------------------------------------------------------------------------*/
/******************************************************************************/
/* REXX Translator                                                            */
/*                                                                            */
/* Primitive Translator Expression Parsing Compound Variable Reference Class  */
/*                                                                            */
/******************************************************************************/
#include <stdlib.h>
#include "RexxCore.h"
#include "StringClass.hpp"
#include "QueueClass.hpp"
#include "StemClass.hpp"
#include "RexxVariableDictionary.hpp"
#include "RexxActivation.hpp"
#include "RexxActivity.hpp"
#include "ExpressionCompoundVariable.hpp"
#include "ExpressionVariable.hpp"
#include "RexxVariable.hpp"
#include "ProtectedObject.hpp"
#include "RexxCompoundTail.hpp"
 
RexxCompoundVariable::RexxCompoundVariable(
    RexxString * _stemName,            /* stem retriever                    */
    size_t       stemIndex,            /* stem lookaside index              */
    RexxQueue  * tailList,             /* list of tails                     */
    size_t       TailCount)            /* count of tails                    */
/******************************************************************************/
/* Function:  Complete compound variable initialization                       */
/******************************************************************************/
{
    this->tailCount= TailCount;          /* set the count (and hash value)    */
    OrefSet(this, this->stemName, _stemName); /* save the associate value          */
    this->index = stemIndex;             /* set the stem index                */
 
    while (TailCount > 0)              /* loop through the variable list    */
    {
        /* copying each variable             */
        OrefSet(this, this->tails[--TailCount], tailList->pop());
    }
}
 
RexxObject * build(
    RexxString * variable_name,         /* full variable name of compound    */
    bool direct )                       /* this is direct access             */
/******************************************************************************/
/* Function:  Build a dynamically created compound variable                   */
/******************************************************************************/
{
    RexxString *   stem;                 /* stem part of compound variable    */
    RexxString *   tail;                 /* tail section string value         */
    RexxQueue  *   tails;                /* tail elements                     */
    RexxObject *   tailPart;             /* tail element retriever            */
    size_t  position;                    /* scan position within compound name*/
    size_t  start;                       /* starting scan position            */
    size_t  length;                      /* length of tail section            */
 
    length = variable_name->getLength(); /* get the string length             */
    position = 0;                        /* start scanning at first character */
                                         /* scan to the first period          */
    while (variable_name->getChar(position) != '.')
    {
        position++;                        /* step to the next character        */
        length--;                          /* reduce the length also            */
    }
    /* extract the stem part             */
    stem = variable_name->extract(0, position + 1);
    ProtectedObject p1(stem);
    /* processing to decompose the name  */
    /* into its component parts          */
 
    tails = new_queue();                 /* get a new list for the tails      */
    ProtectedObject p2(tails);
    position++;                          /* step past previous period         */
    length--;                            /* adjust the length                 */
    if (direct == true)                /* direct access?                    */
    {
        /* extract the tail part             */
        tail = variable_name->extract(position, length);
        tails->push(tail);                 /* add to the tail piece list        */
    }
    else
    {
        while (length > 0)               /* process rest of the variable      */
        {
            start = position;                /* save the start position           */
                                             /* scan for the next period          */
            while (length > 0 && variable_name->getChar(position) != '.')
            {
                position++;                    /* step to the next character        */
                length--;                      /* reduce the length also            */
            }
            /* extract the tail part             */
            tail = variable_name->extract(start, position - start);
            /* have a null tail piece or         */
            /* section begin with a digit?       */
            /* CHM - defect 87: change index start to 0 and compare for range     */
            /* ASCII '0' to '9' to recognize a digit                              */
            if (tail->getLength() == 0 || (tail->getChar(0) >= '0' && tail->getChar(0) <= '9'))
            {
                tailPart = (RexxObject *)tail; /* this is a literal piece           */
            }
            else
            {
                /* create a new variable retriever   */
                tailPart = (RexxObject *)new RexxParseVariable(tail, 0);
            }
            tails->push(tailPart);           /* add to the tail piece list        */
            position++;                      /* step past previous period         */
            length--;                        /* adjust the length                 */
        }
        /* have a trailing period?           */
        if (variable_name->getChar(position - 1) == '.')
        {
            tails->push(OREF_NULLSTRING);    /* add to the tail piece list        */
        }
    }
    /* create and return a new compound  */
    return(RexxObject *)new (tails->getSize()) RexxCompoundVariable(stem, 0, tails, tails->getSize());
}
 
void RexxCompoundVariable::live(size_t liveMark)
/******************************************************************************/
/* Function:  Normal garbage collection live marking                          */
/******************************************************************************/
{
    size_t  i;                           /* loop counter                      */
    size_t  count;                       /* argument count                    */
 
    for (i = 0, count = this->tailCount; i < count; i++)
    {
        memory_mark(this->tails[i]);
    }
    memory_mark(this->stemName);
}
 
void RexxCompoundVariable::liveGeneral(int reason)
/******************************************************************************/
/* Function:  Generalized object marking                                      */
/******************************************************************************/
{
    size_t  i;                           /* loop counter                      */
    size_t  count;                       /* argument count                    */
 
    for (i = 0, count = this->tailCount; i < count; i++)
    {
        memory_mark_general(this->tails[i]);
    }
    memory_mark_general(this->stemName);
}
 
void RexxCompoundVariable::flatten(RexxEnvelope *envelope)
/******************************************************************************/
/* Function:  Flatten an object                                               */
/******************************************************************************/
{
    size_t  i;                           /* loop counter                      */
    size_t  count;                       /* argument count                    */
 
    setUpFlatten(RexxCompoundVariable)
 
    flatten_reference(newThis->stemName, envelope);
    for (i = 0, count = this->tailCount; i < count; i++)
    {
        flatten_reference(newThis->tails[i], envelope);
    }
 
    cleanUpFlatten
}
 
RexxObject * RexxCompoundVariable::evaluate(
    RexxActivation      *context,      /* current activation context        */
    RexxExpressionStack *stack )       /* evaluation stack                  */
/******************************************************************************/
/* Function:  Evaluate a REXX compound variable                               */
/******************************************************************************/
{
    /* and ask it for the value          */
    RexxObject *value = context->evaluateLocalCompoundVariable(stemName, index, &tails[0], tailCount);
 
    stack->push(value);                  /* place on the evaluation stack     */
    return value;                        /* return the located variable       */
}
 
RexxObject  *RexxCompoundVariable::getValue(
  RexxVariableDictionary *dictionary)  /* current activation dictionary     */
/******************************************************************************/
/* Function:  Direct value retrieve of a compound variable                    */
/******************************************************************************/
{
                                       /* resolve the tail element          */
    return dictionary->getCompoundVariableValue(stemName, &tails[0], tailCount);
}
 
RexxObject  *RexxCompoundVariable::getValue(
  RexxActivation *context)             /* current activation dictionary     */
/******************************************************************************/
/* Function:  Direct value retrieve of a compound variable                    */
/******************************************************************************/
{
                                       /* resolve the tail element          */
  return context->getLocalCompoundVariableValue(stemName, index, &tails[0], tailCount);
}
 
RexxObject  *RexxCompoundVariable::getRealValue(RexxVariableDictionary *dictionary)
{
                                       /* resolve the tail element          */
  return dictionary->getCompoundVariableRealValue(stemName, &tails[0], tailCount);
}
 
 
RexxObject  *RexxCompoundVariable::getRealValue(RexxActivation *context)
{
                                       /* resolve the tail element          */
  return context->getLocalCompoundVariableRealValue(stemName, index, &tails[0], tailCount);
}
 
 
void RexxCompoundVariable::set(
  RexxActivation *context,             /* current activation context        */
  RexxObject *value )                  /* new value to assign               */
/******************************************************************************/
/* Function:  Assign a new value to a compound variable                       */
/******************************************************************************/
{
                                       /* the dictionary manages all of these details */
  context->setLocalCompoundVariable(stemName, index, &tails[0], tailCount, value);
}
 
 
void RexxCompoundVariable::set(
  RexxVariableDictionary *dictionary,  /* an object variable dictionary     */
  RexxObject *value )                  /* new value to assign               */
/******************************************************************************/
/* Function:  Assign a new value to a compound variable                       */
/******************************************************************************/
{
                                       /* the dictionary manages all of these details */
  dictionary->setCompoundVariable(stemName, &tails[0], tailCount, value);
}
 
 
bool RexxCompoundVariable::exists(
  RexxActivation *context)             /* current execution context         */
/******************************************************************************/
/* Function:  Check to see if a compound variable exists in a directory       */
/******************************************************************************/
{
                                       /* retrieve the variable value, and  */
                                       /* see it really exists              */
  return context->localCompoundVariableExists(stemName, index, &tails[0], tailCount);
}
 
void RexxCompoundVariable::assign(
    RexxActivation *context,           /* current activation context        */
    RexxExpressionStack *stack,        /* current evaluation stack          */
    RexxObject     *value )            /* new value to assign               */
/******************************************************************************/
/* Function:  Assign a value to a compound variable                           */
/******************************************************************************/
{
    /* the context manages the assignment details */
    context->assignLocalCompoundVariable(stemName, index, (RexxObject **)&tails[0], tailCount, value);
}
 
void RexxCompoundVariable::drop(
    RexxActivation *context)           /* current activation context        */
/******************************************************************************/
/* Function:  Drop a compound variable                                        */
/******************************************************************************/
{
                                       /* set the compound value            */
  context->dropLocalCompoundVariable(stemName, index, &tails[0], tailCount);
}
 
void RexxCompoundVariable::drop(RexxVariableDictionary *dictionary)
{
                                       /* the dictionary manages all of these details */
    dictionary->dropCompoundVariable(stemName, &tails[0], tailCount);
}
 
 
void RexxCompoundVariable::procedureExpose(
  RexxActivation      *context,        /* current activation context        */
  RexxActivation      *parent,         /* the parent activation context     */
  RexxExpressionStack *stack)          /* current evaluation stack          */
/******************************************************************************/
/* Function:  Expose a compound variable                                      */
/******************************************************************************/
{
    /* first get (and possible create) the compound variable in the */
    /* parent context. */
    RexxCompoundElement *variable = parent->exposeLocalCompoundVariable(stemName, index, (RexxObject **)&tails[0], tailCount);
    /* get the stem index from the current level.  This may end up */
    /* creating the stem that holds the exposed value. */
    RexxStem *stem_table = context->getLocalStem(stemName, index);
    /* have the stem expose this */
    stem_table->expose(variable);
    /* trace resolved compound name */
    context->traceCompoundName(stemName, (RexxObject **)&tails[0], tailCount, variable->getName());
}
 
 
void RexxCompoundVariable::expose(
  RexxActivation      *context,        /* current activation context        */
  RexxExpressionStack *stack,          /* current evaluation stack          */
                                       /* variable scope we're exposing from*/
  RexxVariableDictionary *object_dictionary)
/******************************************************************************/
/* Function:  Expose a compound variable                                      */
/******************************************************************************/
{
    /* get the stem in the source dictionary */
    RexxStem *source_stem = object_dictionary->getStem(stemName);
                                          /* new tail for compound             */
    RexxCompoundTail resolved_tail(context, &tails[0], tailCount);
    /* first get (and possible create) the compound variable in the */
    /* object context. */
    RexxCompoundElement *variable = source_stem->exposeCompoundVariable(&resolved_tail);
    /* get the stem index from the current level.  This may end up */
    /* creating the stem that holds the exposed value. */
    RexxStem *stem_table = context->getLocalStem(stemName, index);
    /* have the stem expose this */
    stem_table->expose(variable);
    /* tracing intermediate values?      */
    if (context->tracingIntermediates()) {
        /* trace resolved compound name */
        context->traceCompoundName(stemName, (RexxObject **)&tails[0], tailCount, variable->getName());
    }
}
 
 
void RexxCompoundVariable::setGuard(
  RexxActivation *context )            /* current activation context        */
/******************************************************************************/
/* Function:  Set a guard wait in a compound variable                         */
/******************************************************************************/
{
                                       /* get the variable item             */
  RexxCompoundElement *variable = context->getLocalCompoundVariable(stemName, index, &tails[0], tailCount);
  variable->inform(ActivityManager::currentActivity);   /* mark the variable entry           */
}
 
void RexxCompoundVariable::clearGuard(
  RexxActivation *context )            /* current activation context        */
/******************************************************************************/
/* Function:  Clear a guard wait on a compound variable                       */
/******************************************************************************/
{
                                       /* get the variable item             */
  RexxCompoundElement *variable = context->getLocalCompoundVariable(stemName, index, &tails[0], tailCount);
  variable->uninform(ActivityManager::currentActivity); /* mark the variable entry           */
}
 
void * RexxCompoundVariable::operator new(size_t size,
    size_t tailCount)                   /* count of tails                    */
/******************************************************************************/
/* Function:  Create a new compound variable object                           */
/******************************************************************************/
{
    if (tailCount == 0)
    {
        // this object is normal sized, minus the dummy tail element
        return new_object(size - sizeof(RexxObject *), T_CompoundVariableTerm);
    }
    else
    {
        /* Get new object                    */
        return new_object(size + ((tailCount - 1) * sizeof(RexxObject *)), T_CompoundVariableTerm);
    }
}