static exprType getenvFunc(void)
{
exprType stringType;
TRACE(lstFile, "[getenvFunc]");
/* FORM: <string_var> = getenv(<string>) */
checkLParen();
/* Get the string expression representing the environment variable
* name.
*/
stringType = expression(exprString, NULL);
/* Two possible kinds of strings could be returned.
* Anything else other then 'exprString' would be an error (but
* should happen).
*/
if ((stringType != exprString) && (stringType != exprStkString))
{
error(eINVARG);
}
pas_BuiltInFunctionCall(lbGETENV);
checkRParen();
return exprCString;
}
static void valProc(void) /* VAL procedure */
{
int size;
TRACE(lstFile, "[valProc]");
/* Declaration:
* procedure val(const S : string; var V; var Code : word);
*
* Description:
* val() converts the value represented in the string S to a numerical
* value, and stores this value in the variable V, which can be of type
* Longint, Real and Byte. If the conversion isn��t succesfull, then the
* parameter Code contains the index of the character in S which
* prevented the conversion. The string S is allowed to contain spaces
* in the beginning.
*
* The string S can contain a number in decimal, hexadecimal, binary or
* octal format, as described in the language reference.
*
* Errors:
* If the conversion doesn��t succeed, the value of Code indicates the
* position where the conversion went wrong.
*/
/* Skip over the 'val' identifer */
getToken();
/* Setup the actual-parameter-list */
size = actualParameterList(valSymbol);
/* Generate the built-in procedure call. NOTE the procedure call
* logic will release the parameters from the stack saving us from
* having to generate the INDS here.
*/
pas_BuiltInFunctionCall(lbVAL);
} /* end writelnProc */
static void pas_StringAssignment(STYPE *varPtr, STYPE *typePtr)
{
exprType stringKind;
TRACE(lstFile,"[pas_StringAssignment]");
/* FORM: <variable OR function identifer> := <expression> */
/* Verify that the assignment token follows the indentifier */
if (token != tASSIGN) error (eASSIGN);
else getToken();
/* Get the expression after assignment token. We'll take any kind
* of string expression. This is a hack to handle calls to system
* functions that return exprCString pointers that must be converted
* to exprString records upon assignment.
*/
stringKind = expression(exprAnyString, typePtr);
/* Place the address of the destination string structure instance on the
* stack.
*/
pas_GenerateStackReference(opLAS, varPtr);
/* Check if this is an assignment to a global allocated string, or
* to a stack reference to an allocated string.
*/
if (varPtr->sKind == sRSTRING)
{
/* It is an assignment to a string reference --
* Generate a runtime library call to copy the destination
* string string into the pascal string instance. The particular
* runtime call will account for any necesary string type conversion.
*/
if ((stringKind == exprString) || (stringKind == exprStkString))
{
/* It is a pascal string type. Current stack representation is:
*
* TOS(0)=address of dest string reference
* TOS(1)=length of source string
* TOS(2)=pointer to source string
*/
pas_BuiltInFunctionCall(lbSTR2RSTR);
}
else if (stringKind == exprCString)
{
/* It is a 32-bit C string point. Current stack representation is:
*
* TOS(0)=address of dest string reference
* TOS(1)=MS 16-bits of 32-bit C source string pointer
* TOS(2)=LS 16-bits of 32-bit C source string pointer
*/
pas_BuiltInFunctionCall(lbCSTR2RSTR);
}
}
else
{
/* It is an assignment to a allocated Pascal string --
* Generate a runtime library call to copy the destination
* string string into the pascal string instance. The particular
* runtime call will account for any necesary string type conversion.
*/
if ((stringKind == exprString) || (stringKind == exprStkString))
{
/* It is a pascal string type. Current stack representation is:
*
* TOS(0)=address of dest string hdr
* TOS(1)=length of source string
* TOS(2)=pointer to source string
*/
pas_BuiltInFunctionCall(lbSTR2STR);
}
else if (stringKind == exprCString)
{
/* It is a 32-bit C string point. Current stack representation is:
*
* TOS(0)=address of dest string hdr
* TOS(1)=MS 16-bits of 32-bit C source string pointer
* TOS(2)=LS 16-bits of 32-bit C source string pointer
*/
pas_BuiltInFunctionCall(lbCSTR2STR);
}
}
/* else ... type mismatch error already reported by expression() */
}