838 lines
23 KiB
C++
838 lines
23 KiB
C++
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// RPN.C -- expression evaluator
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//
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// Copyright (c) 1988-1990, Microsoft Corporation. All rights reserved.
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//
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// Purpose:
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// This module contains NMAKE's expression evaluator routines.
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//
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// Revision History:
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// 15-Nov-1993 JdR Major speed improvements
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// 15-Oct-1993 HV Use tchar.h instead of mbstring.h directly, change STR*() to _ftcs*()
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// 10-May-1993 HV Add include file mbstring.h
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// Change the str* functions to STR*
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// 04-Dec-1989 SB Add prototype for match() and chkInvokeAndPush()
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// 09-Oct-1989 SB Added HACK to handle pointer arithmetic quirks; Done to
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// avoid rewriting entire module
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// 08-Oct-1989 SB '!if' expressions can be decimal, octal or hex now
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// 05-Apr-1989 SB made all funcs NEAR; Reqd to make all function calls NEAR
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// 19-Sep-1988 RB Split ptr_to_string(). Process ESCH in program invocations.
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// 17-Aug-1988 RB Clean up.
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// 28-Jun-1988 rj Added doCmd parameter to execLine.
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// 23-Jun-1988 rj Add parameter to execLine (no echo of command).
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// 25-May-1988 rb Change isspace to _istspace, isdigit to _istdigit.
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#include "precomp.h"
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#pragma hdrstop
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#include "rpn.h"
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char * GetEndQuote(void);
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char * GetEndBracket(void);
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void check_syntax_error(UCHAR);
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void type_and_val(UCHAR, INT_PTR);
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void pushIntoList(void);
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void printList(void);
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BOOL handleExpr(void);
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BOOL handleExists(char*);
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BOOL handleDefines(char*);
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void getTok(void);
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BOOL do_binary_op(UCHAR);
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BOOL do_unary_op(UCHAR);
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UCHAR match(char *tokPtr);
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void chkInvocAndPush(RPNINFO *pListPtr);
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#define TEMPSTACKSIZE 512 // size of temporary stack
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#define LISTSIZE 1024 // size of list of rpn-form items
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RPNINFO tempStack[TEMPSTACKSIZE]; // temporary/operand stack
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RPNINFO rpnList[LISTSIZE]; // list of items in rpn order
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char * text; // pointer to expr text in lbufPtr
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UCHAR prevTok; // initial token put on tempstack
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BOOL done; // true if there are no more tokens
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UCHAR errRow; // first token is '(' so error table
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// row val is 3. See check_syntax....
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RPNINFO * pTop; // top item on tempStack
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RPNINFO * pList; // next free slot in list
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RPNINFO * pEnd = &(tempStack[TEMPSTACKSIZE-1]);
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RPNINFO * pListEnd = &(rpnList[LISTSIZE-1]);
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RPNINFO tokRec;
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// do_binary_op() - do operation on two stack operands
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//
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// arguments: type - operator type code
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//
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// actions : pops first operand from the stack (tempStack).
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// checks the types of the two operands (the operand
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// that was popped as well as the operand currently
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// on top of the stack).
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// if both operands are integers then do the operation
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// else if both operands are strings and operation is
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// the equality operation then do it.
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// else return FALSE ( illegal operation )
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//
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// modifies : tempStack - top element will now be the result of
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// the operation.
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BOOL
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do_binary_op(
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UCHAR type
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)
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{
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INT_PTR *left;
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INT_PTR *right;
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RPNINFO *pOldTop;
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pOldTop = pTop--; // pop one item off stack, with a ptr to it
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right = &pOldTop->valPtr;
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left = &pTop->valPtr;
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if ((pOldTop->type == INTEGER) && (pTop->type == INTEGER)) {
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switch (type) {
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case LOGICAL_OR:
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*left = *left || *right;
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break;
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case LOGICAL_AND:
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*left = *left && *right;
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break;
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case BIT_OR:
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*left |= *right;
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break;
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case BIT_XOR:
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*left ^= *right;
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break;
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case BIT_AND:
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*left &= *right;
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break;
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case NOT_EQUAL:
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*left = *right != *left;
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break;
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case EQUAL:
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*left = *right == *left;
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break;
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case GREATER_THAN:
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*left = *left > *right;
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break;
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case LESS_THAN:
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*left = *left < *right;
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break;
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case GREATER_EQ:
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*left = *left >= *right;
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break;
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case LESS_EQ:
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*left = *left <= *right;
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break;
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case SHFT_RIGHT:
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*left >>= *right;
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break;
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case SHFT_LEFT:
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*left <<= *right;
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break;
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case BINARY_MINUS:
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*left -= *right;
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break;
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case ADD:
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*left += *right;
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break;
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case MODULUS:
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if (!*right)
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makeError(line, DIVIDE_BY_ZERO);
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*left %= *right;
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break;
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case DIVIDE:
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if (!*right)
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makeError(line, DIVIDE_BY_ZERO);
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*left /= *right;
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break;
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case MULTIPLY:
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*left *= *right;
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break;
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default:
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return(FALSE);
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break;
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}
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} else if ((pOldTop->type == STR) &&
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(pTop->type == STR) &&
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((type == EQUAL) || (type == NOT_EQUAL))) {
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pTop->type = INTEGER;
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*left = !_tcscmp((char *) *left, (char *) *right);
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if (type == NOT_EQUAL) {
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if (!do_unary_op(LOGICAL_NOT)) {
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return(FALSE);
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}
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}
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} else {
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return(FALSE);
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}
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return(TRUE);
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}
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// do_unary_op() - do operation on top stack operand
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//
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// arguments: type - operator type code
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//
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// actions : checks the type of the top operand on the stack
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// if operand is an integer then do the operation
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// else return FALSE ( illegal operation )
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//
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// modifies : tempStack - top element will now be the result of
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// the operation.
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BOOL
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do_unary_op(
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UCHAR type
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)
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{
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INT_PTR *top;
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top = &pTop->valPtr;
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if (pTop->type == INTEGER) {
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switch (type) {
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case UNARY_MINUS:
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*top = -*top;
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break;
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case COMPLEMENT:
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*top = ~*top;
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break;
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case LOGICAL_NOT:
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*top = !*top;
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break;
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default:
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return(FALSE);
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break;
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}
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} else {
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return(FALSE);
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}
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return(TRUE);
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}
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// GetEndQuote
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//
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// Return the pointer to the next double-quote character in text. A
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// double-quote followed immediately by a double-quote is skipped.
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//
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// text : the global ptr to the buffer is moved up beyond this string.
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char *
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GetEndQuote()
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{
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char *pStart;
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for (pStart = ++text; *text; ++text)
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if (*text == '\"') {
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if (text[1] == '\"')
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++text;
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else
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break;
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}
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if (!*text)
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makeError(line, SYNTAX_MISSING_END_CHAR, '\"');
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*text++ = '\0'; // null byte over closing quote
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return(pStart);
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}
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// GetEndBracket
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//
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// Lexes a program invocation.
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//
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// Program invocation is of the form: [ prog <arglist> ].
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// Process escaped ']' here because this is where we do the lexing.
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//
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// text : the global ptr to the buffer is moved up beyond this string.
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char *
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GetEndBracket()
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{
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char *pStart;
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for (pStart = ++text; *text; text = _tcsinc (text)) {
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if (*text == ESCH && text[1] == ']')
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memmove(text, text + 1, 1 + _tcslen(text + 1));
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else if (*text == ']')
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break;
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}
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if (!*text)
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makeError(line, SYNTAX_MISSING_END_CHAR, ']');
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*text++ = '\0'; // null byte over closing bracket
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return(pStart);
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}
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// check_syntax_error() - check if there is a syntax error in expr
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//
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// arguments: type - type of the current token
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//
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// actions: checks the type of the current token against the type
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// of the previous token.
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//
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// ERROR_TABLE :
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// 2nd tok
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//
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// alpha op unary_op ( )
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// ------------------------------------------------
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// alpha | 0 | 1 | 0 | 0 | 1 |
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// -------------------------------------------------
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// op | 1 | 0 | 1 | 1 | 0 |
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// -------------------------------------------------
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// unary_op | 1 | 0 | 0 | 1 | 0 |
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// -------------------------------------------------
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// ( | 1 | 0 | 1 | 1 | 0 |
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// -------------------------------------------------
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// ) | 0 | 1 | 0 | 0 | 1 |
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// -------------------------------------------------
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// 1st tok.
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//
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// alpha : a primary ( integer, str, prog. invoc. )
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// op : a binary operator
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// unary_op : a unary operator ( ~, !, - ). A ZERO in the slot => error
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//
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// NOTE: ANY CHANGES TO THE TYPE VALUES WILL AFFECT THIS ROUTINE.
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void
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check_syntax_error(
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UCHAR newTok
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)
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{
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extern UCHAR errTable[5][5];
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extern UCHAR errRow;
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UCHAR errCol;
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if (newTok == LEFT_PAREN)
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errCol = 3;
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else if (newTok == RIGHT_PAREN)
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errCol = 4;
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else if (newTok > LOGICAL_NOT)
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errCol = 0;
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else if (newTok > MULTIPLY)
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errCol = 2;
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else
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errCol = 1;
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if (!errTable[errRow][errCol])
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makeError(line, SYNTAX_INVALID_EXPR);
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errRow = errCol; // this becomes the first token the next time
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}
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// type_and_val()
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//
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// arguments: type - the type code of the present operator.
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// val - ptr to a str/or integer
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//
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// initialises a record with the type code, after checking for any
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// syntax errors. The new token is checked against the previous token
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// for illegal combinations of tokens.
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// initialises the record with the integer value/string ptr.
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void
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type_and_val(
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UCHAR type,
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INT_PTR val
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)
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{
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extern RPNINFO tokRec; // returned to handleExpr
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extern UCHAR prevTok; // token last seen
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check_syntax_error(type);
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prevTok = type;
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tokRec.type = type;
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tokRec.valPtr = val;
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}
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// match()
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//
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// arguments: tokPtr - ptr to a token string ( in tokTable )
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//
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// actions : looks for a substring in the expression buffer
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// pointed to by 'text', that matches the given token.
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// if substring found, returns TRUE, else returns FALSE.
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UCHAR
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match(
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char *tokPtr
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)
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{
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extern char *text;
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char *t = text;
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while (*tokPtr && (*t == *tokPtr)) {
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t++;
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tokPtr++;
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}
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if (!*tokPtr) {
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text = t;
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return(TRUE);
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}
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return(FALSE);
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}
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// getTok()
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//
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// arguments: none
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//
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// gets a token from the expression buffer.
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// if the current char from the buffer is a space/tab, skip space/tabs
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// until we get a non-space char ( could be NULL char ).
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// Check if we are now at the beginning of one of the tokens in the
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// tokenTable. This covers most tokens.
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// Check if we have a minus. If a minus and the previous token was an
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// integer, this is a binary minus, else a unary minus.
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// If the current char is a double-quote, we are at the start of a
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// string-token.
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// If the current char is a '[', we are at the start of a program
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// invocation. In both cases, the escape character is '\\'.
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// If current char is a digit, we have a constant ( integer ).
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// Else we have defined(ID).
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// If none of the above, if current char is NULL, break out, else
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// report error ( illegal character string has been found ).
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//
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// If we came to the NULL char at the end of the buffer, set global
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// flag 'done' to TRUE, return a RIGHT_PAREN to match the opening
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// LEFT_PAREN.
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//
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//
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// modifies: text : ptr to expression buffer.
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// prevTok: thru' calls to type_and_val().
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// done : at end of buffer
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// errRow : index into error table, thru calls to
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// type_and_val()
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// returns : token in tokRec(global, static to the module). The
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// token has the new type/integer/ptr values.
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void
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getTok()
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{
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extern UCHAR prevTok;
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extern BOOL done;
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char c;
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TOKTABREC *p;
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char *ptr;
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long constant;
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c = *text;
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if (c == ' ' || c == '\t') {
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while(_istspace(c))
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c = *++text; // skip white spaces
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}
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if (IS_OPERATORCHAR(c)) {
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for (p = tokTable; p->op_str && !match(p->op_str); p++)
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;
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} else {
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// make p point to last entry in table
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p = &tokTable[(sizeof(tokTable) / sizeof(TOKTABREC)) - 1];
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}
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if (p->op_str) {
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type_and_val(p->op, 0);
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} else
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if (c == '-') { // now check if binary or unary minus to be returned
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text++;
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if (prevTok == INTEGER)
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type_and_val(BINARY_MINUS, 0);
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else
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type_and_val(UNARY_MINUS, 0);
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} else
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if (c == '\"') {
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type_and_val(STR, (INT_PTR) GetEndQuote());
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} else
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if (c == '[') {
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type_and_val(PROG_INVOC_STR, (INT_PTR) GetEndBracket());
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} else { // integers and IDs handled here
|
||
|
if (_istdigit(c)) {
|
||
|
char *pNumber = text;
|
||
|
|
||
|
errno = 0; // Accept decimal, octal or hex no (richgi)
|
||
|
constant = strtol(text, &text, 0);
|
||
|
if (errno == ERANGE) {
|
||
|
*text = '\0';
|
||
|
makeError(line, CONST_TOO_BIG, pNumber);
|
||
|
}
|
||
|
|
||
|
if (_totupper(*text) == 'L')
|
||
|
text++;
|
||
|
type_and_val(INTEGER, constant);
|
||
|
} else { // defined(ID) comes here
|
||
|
if (c) {
|
||
|
if (!_tcsnicmp(text, "DEFINED", 7)) {
|
||
|
if (!(ptr = _tcschr(text, '(')))
|
||
|
makeError(line, SYNTAX_INVALID_EXPR);
|
||
|
ptr++;
|
||
|
text = ptr + _tcscspn(ptr, ")");
|
||
|
*text++ = '\0';
|
||
|
type_and_val(INTEGER, handleDefines(ptr));
|
||
|
}
|
||
|
else if (!_tcsnicmp(text, "EXIST", 5)) {
|
||
|
if (!(ptr = _tcschr(text, '(')))
|
||
|
makeError(line, SYNTAX_INVALID_EXPR);
|
||
|
ptr++;
|
||
|
text = ptr + _tcscspn(ptr, ")");
|
||
|
*text++ = '\0';
|
||
|
type_and_val(INTEGER, handleExists(ptr));
|
||
|
}
|
||
|
else
|
||
|
makeError(line, SYNTAX_INVALID_EXPR);
|
||
|
} else { // we are now at the end of the string (c is null)
|
||
|
done = TRUE;
|
||
|
type_and_val(RIGHT_PAREN, 0); // this is the last token
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
|
||
|
|
||
|
// chkInvocAndPush() - check if program invocation required
|
||
|
//
|
||
|
// arguments: pListPtr - might have a program invocation string
|
||
|
// present.
|
||
|
//
|
||
|
// actions : if this is a program invocation string, make the
|
||
|
// program invocation.
|
||
|
// the return value is got and placed on the stack.
|
||
|
// the type of the new stack element is now INTEGER.
|
||
|
// else place list item on stack.
|
||
|
//
|
||
|
// in either case it moves one item from list to stack.
|
||
|
|
||
|
void
|
||
|
chkInvocAndPush(
|
||
|
RPNINFO *pListPtr
|
||
|
)
|
||
|
{
|
||
|
++pTop;
|
||
|
if (pListPtr->type == PROG_INVOC_STR) {
|
||
|
pTop->valPtr = execLine((char *) pListPtr->valPtr, FALSE, TRUE, FALSE, NULL);
|
||
|
pTop->type = INTEGER;
|
||
|
} else {
|
||
|
*pTop = *pListPtr;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
|
||
|
// processList()
|
||
|
//
|
||
|
// arguments: none
|
||
|
//
|
||
|
// actions : remove an item from the list.
|
||
|
// if the item is an operand, place it on the operand
|
||
|
// stack (tempStack).
|
||
|
// if the operand is a program invocation string, make
|
||
|
// the invocation, place the return code on stack.
|
||
|
// if the item is an operator, call the function to
|
||
|
// do the operation on one/two elements on tempStack.
|
||
|
//
|
||
|
// finally, check if there is exactly one item on stack.
|
||
|
// if this item has a value of zero, return FALSE.
|
||
|
// else return TRUE.
|
||
|
// if more than one item on stack, abort with error.
|
||
|
//
|
||
|
// modifies: pTop - ptr to top of tempStack.
|
||
|
// pList - ptr to next position in list.
|
||
|
|
||
|
BOOL
|
||
|
processList()
|
||
|
{
|
||
|
extern RPNINFO *pList;
|
||
|
extern RPNINFO *pTop;
|
||
|
RPNINFO *pTemp;
|
||
|
BOOL (* func)(UCHAR);
|
||
|
|
||
|
for (pTemp = rpnList; pTemp < pList; pTemp++) {
|
||
|
if (pTemp->type > LOGICAL_NOT) { // operand
|
||
|
chkInvocAndPush(pTemp);
|
||
|
} else {
|
||
|
if (pTemp->type > MULTIPLY)
|
||
|
func = do_unary_op;
|
||
|
else
|
||
|
func = do_binary_op;
|
||
|
|
||
|
if (!(*func)(pTemp->type))
|
||
|
makeError(line, BAD_OP_TYPES);
|
||
|
}
|
||
|
}
|
||
|
|
||
|
if ((pTop == tempStack) && (pTop->type == INTEGER))
|
||
|
if (!pTop->valPtr)
|
||
|
return(FALSE);
|
||
|
else
|
||
|
return(TRUE);
|
||
|
else
|
||
|
makeError(line, SYNTAX_INVALID_EXPR);
|
||
|
|
||
|
return(FALSE);
|
||
|
}
|
||
|
|
||
|
|
||
|
// pushIntoList()
|
||
|
//
|
||
|
// arguments: none
|
||
|
//
|
||
|
// actions : pops an item from the tempStack and pushes it onto
|
||
|
// the list. checks list for overflow ( internal error )
|
||
|
// and tempStack for underflow ( syntax error in expr ).
|
||
|
//
|
||
|
// modifies: tempTop - index of top of tempStack.
|
||
|
// nextInList - index to next position in list.
|
||
|
|
||
|
void
|
||
|
pushIntoList()
|
||
|
{
|
||
|
if (pTop < tempStack)
|
||
|
makeError(line, SYNTAX_INVALID_EXPR);
|
||
|
|
||
|
if (pList > pListEnd)
|
||
|
makeError(line, EXPR_TOO_LONG_INTERNAL);
|
||
|
|
||
|
#if !defined(NDEBUG)
|
||
|
// Keep track of the high water mark on the stack just for grins
|
||
|
{
|
||
|
static int iStackMax = 0;
|
||
|
if ( pList - rpnList > iStackMax )
|
||
|
iStackMax = (int) (pList - rpnList);
|
||
|
}
|
||
|
#endif
|
||
|
|
||
|
*pList++ = *pTop--;
|
||
|
}
|
||
|
|
||
|
|
||
|
// handleExpr()
|
||
|
//
|
||
|
// arguments: text - pointer to the buffer that has the expression.
|
||
|
//
|
||
|
// actions : calls getTok() to get tokens from the buffer. Places
|
||
|
// tokens in a tempStack, and moves them into a list in
|
||
|
// reverse-polish order.
|
||
|
//
|
||
|
// We need the list so that ALL syntax errors are caught
|
||
|
// BEFORE processing of the expression begins (especially
|
||
|
// program invocations that have side effects)
|
||
|
//
|
||
|
// Once the list is available, an operand stack is used
|
||
|
// Items are popped and pushed from this stack by the
|
||
|
// evaluation routines (add, mult, negate etc.)
|
||
|
//
|
||
|
// we don't really need a separate operand stack. the
|
||
|
// tempStack has served its purpose when the list is
|
||
|
// formed and so it may be used for operand processing.
|
||
|
|
||
|
BOOL
|
||
|
handleExpr()
|
||
|
{
|
||
|
extern RPNINFO tokRec;
|
||
|
BOOL fRParen; // was the token got a right paren?
|
||
|
extern BOOL done;
|
||
|
extern RPNINFO *pTop, *pList;
|
||
|
extern UCHAR errRow;
|
||
|
extern UCHAR prevTok;
|
||
|
|
||
|
pTop = tempStack;
|
||
|
pList = rpnList;
|
||
|
done = FALSE;
|
||
|
errRow = 3; // row for the first token put in,left paren
|
||
|
prevTok = LEFT_PAREN;
|
||
|
type_and_val(LEFT_PAREN, 0);
|
||
|
*pTop = tokRec;
|
||
|
|
||
|
while (!done) { // while there are more tokens in buffer
|
||
|
getTok();
|
||
|
fRParen = FALSE;
|
||
|
if (tokRec.type != LEFT_PAREN) {
|
||
|
while (precVector[tokRec.type] <= precVector[pTop->type]) {
|
||
|
if (!precVector[tokRec.type]) { // if RIGHT_PAREN pop till a
|
||
|
// left paren is seen
|
||
|
while (pTop->type != LEFT_PAREN)
|
||
|
pushIntoList();
|
||
|
fRParen = TRUE;
|
||
|
if (pTop < tempStack) {
|
||
|
makeError(line, SYNTAX_INVALID_EXPR);
|
||
|
} else {
|
||
|
pTop--; // pop the left paren
|
||
|
break;
|
||
|
}
|
||
|
} else {
|
||
|
pushIntoList();
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
// if token is a left paren, it has to go on the stack
|
||
|
if (!fRParen) {
|
||
|
if (pTop == pEnd)
|
||
|
makeError(line, EXPR_TOO_LONG_INTERNAL);
|
||
|
else
|
||
|
*++pTop = tokRec;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
// check the stack here for not empty state
|
||
|
if (pTop != tempStack - 1)
|
||
|
makeError(line, SYNTAX_INVALID_EXPR);
|
||
|
return(processList());
|
||
|
}
|
||
|
|
||
|
|
||
|
// handleDefines()
|
||
|
//
|
||
|
// arguments: t pointer to buffer that has the identifier
|
||
|
//
|
||
|
// actions: Checks if one of 'ID' is present.
|
||
|
// Aborts with error if more IDs present.
|
||
|
// Is called for ifdef/ifndef/defined(ID).
|
||
|
//
|
||
|
// returns : TRUE if ID found in table. FALSE otherwise.
|
||
|
|
||
|
BOOL
|
||
|
handleDefines(
|
||
|
char *t
|
||
|
)
|
||
|
{
|
||
|
char *s;
|
||
|
|
||
|
s = _tcstok(t, " \t");
|
||
|
if (_tcstok(NULL, " \t")) {
|
||
|
makeError(line, SYNTAX_UNEXPECTED_TOKEN, s);
|
||
|
}
|
||
|
|
||
|
if (!s) {
|
||
|
makeError(line, MISSING_ARG_BEFORE_PAREN);
|
||
|
}
|
||
|
|
||
|
if (findMacro(s)) {
|
||
|
return(TRUE);
|
||
|
}
|
||
|
|
||
|
return(FALSE);
|
||
|
}
|
||
|
|
||
|
|
||
|
// handleExists()
|
||
|
//
|
||
|
// arguments: t pointer to buffer that has the identifier
|
||
|
//
|
||
|
// actions: Checks if 'name' is a valid file/directory
|
||
|
// Aborts with error if more names present.
|
||
|
// Is called for exist(name).
|
||
|
//
|
||
|
// returns : TRUE if ID found in table. FALSE otherwise.
|
||
|
|
||
|
BOOL
|
||
|
handleExists(
|
||
|
char *_t
|
||
|
)
|
||
|
{
|
||
|
char *s;
|
||
|
char *szUnQuoted;
|
||
|
BOOL fResult = FALSE;
|
||
|
char *szDelim;
|
||
|
char *t;
|
||
|
|
||
|
// make local copy, strip blank space before and after string
|
||
|
char *tSav = t = makeString(_t);
|
||
|
while (*t && WHITESPACE (*t)) {
|
||
|
t++;
|
||
|
}
|
||
|
s = t + _tcslen(t);
|
||
|
while (s > t) {
|
||
|
s = _tcsdec(t, s);
|
||
|
if (WHITESPACE (*s)) {
|
||
|
*s = '\0';
|
||
|
}
|
||
|
else {
|
||
|
break;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
szDelim = ('\"' == *t) ? "\t" : " \t";
|
||
|
// DS 15360: if id starts with a quote,
|
||
|
// use "\t" instead of " \t" in _tcstok
|
||
|
// (handle paths with embedded spaces)
|
||
|
s = _tcstok(t, szDelim);
|
||
|
if (_tcstok(NULL, szDelim)) {
|
||
|
makeError(line, SYNTAX_UNEXPECTED_TOKEN, s);
|
||
|
}
|
||
|
|
||
|
if (NULL == s || NULL == (szUnQuoted = unQuote(s))) { // handle quoted names
|
||
|
makeError(line, MISSING_ARG_BEFORE_PAREN);
|
||
|
}
|
||
|
|
||
|
if (!_access(szUnQuoted, 0x00)) { // existence check
|
||
|
fResult = TRUE;
|
||
|
}
|
||
|
|
||
|
FREE(szUnQuoted);
|
||
|
FREE(tSav);
|
||
|
|
||
|
return(fResult);
|
||
|
}
|
||
|
|
||
|
|
||
|
// evalExpr()
|
||
|
//
|
||
|
// arguments: t pointer to buffer that has the expression
|
||
|
// kind specifies if it is if/ifdef/ifndef etc.
|
||
|
//
|
||
|
//
|
||
|
//
|
||
|
// returns : TRUE if expression evaluates to true.
|
||
|
// FALSE otherwise.
|
||
|
|
||
|
BOOL
|
||
|
evalExpr(
|
||
|
char *t,
|
||
|
UCHAR kind
|
||
|
)
|
||
|
{
|
||
|
if (!*t) {
|
||
|
makeError(line, SYNTAX_MISSING_DIRECTIVE);
|
||
|
}
|
||
|
|
||
|
switch (kind) {
|
||
|
case IFDEF_TYPE:
|
||
|
case ELSE_IFDEF_TYPE:
|
||
|
return(handleDefines(t));
|
||
|
|
||
|
case IFNDEF_TYPE:
|
||
|
case ELSE_IFNDEF_TYPE:
|
||
|
return((BOOL)!handleDefines(t));
|
||
|
|
||
|
default:
|
||
|
text = t;
|
||
|
return(handleExpr());
|
||
|
}
|
||
|
}
|