//
// Do all token-pasting related combining of two pasted tokens when getting a
// stream of tokens from a replacement list. Degenerates to no processing if a
// replacement list is not the source of the token stream.
//
int TPpContext::tokenPaste(int token, TPpToken& ppToken)
{
// starting with ## is illegal, skip to next token
if (token == PpAtomPaste) {
_parseContext.ppError(ppToken.loc, "unexpected location", "##", "");
return scanToken(&ppToken);
}
int resultToken = token; // "foo" pasted with "35" is an identifier, not a number
// ## can be chained, process all in the chain at once
while (peekPasting()) {
TPpToken pastedPpToken;
// next token has to be ##
token = scanToken(&pastedPpToken);
assert(token == PpAtomPaste);
// This covers end of macro expansion
if (endOfReplacementList()) {
_parseContext.ppError(ppToken.loc, "unexpected location; end of replacement list", "##", "");
break;
}
// get the token after the ##
token = scanToken(&pastedPpToken);
// This covers end of argument expansion
if (token == tMarkerInput::marker) {
_parseContext.ppError(ppToken.loc, "unexpected location; end of argument", "##", "");
break;
}
// get the token text
switch (resultToken) {
case PpAtomIdentifier:
// already have the correct text in token.names
break;
case '=':
case '!':
case '-':
case '~':
case '+':
case '*':
case '/':
case '%':
case '<':
case '>':
case '|':
case '^':
case '&':
case PpAtomRight:
case PpAtomLeft:
case PpAtomAnd:
case PpAtomOr:
case PpAtomXor:
strcpy(ppToken.name, atomStrings.getString(resultToken));
strcpy(pastedPpToken.name, atomStrings.getString(token));
break;
default:
_parseContext.ppError(ppToken.loc, "not supported for these tokens", "##", "");
return resultToken;
}
// combine the tokens
if (strlen(ppToken.name) + strlen(pastedPpToken.name) > MaxTokenLength) {
_parseContext.ppError(ppToken.loc, "combined tokens are too long", "##", "");
return resultToken;
}
strncat(ppToken.name, pastedPpToken.name, MaxTokenLength - strlen(ppToken.name));
// correct the kind of token we are making, if needed (identifiers stay identifiers)
if (resultToken != PpAtomIdentifier) {
int newToken = atomStrings.getAtom(ppToken.name);
if (newToken > 0)
resultToken = newToken;
else
_parseContext.ppError(ppToken.loc, "combined token is invalid", "##", "");
}
}
return resultToken;
}
//
// Do all token-pasting related combining of two pasted tokens when getting a
// stream of tokens from a replacement list. Degenerates to no processing if a
// replacement list is not the source of the token stream.
//
int TPpContext::tokenPaste(int token, TPpToken& ppToken)
{
// starting with ## is illegal, skip to next token
if (token == PpAtomPaste) {
parseContext.ppError(ppToken.loc, "unexpected location", "##", "");
return scanToken(&ppToken);
}
int resultToken = token; // "foo" pasted with "35" is an identifier, not a number
// ## can be chained, process all in the chain at once
while (peekPasting()) {
TPpToken pastedPpToken;
// next token has to be ##
token = scanToken(&pastedPpToken);
assert(token == PpAtomPaste);
// This covers end of macro expansion
if (endOfReplacementList()) {
parseContext.ppError(ppToken.loc, "unexpected location; end of replacement list", "##", "");
break;
}
// Get the token(s) after the ##.
// Because of "space" semantics, and prior tokenization, what
// appeared a single token, e.g. "3A", might have been tokenized
// into two tokens "3" and "A", but the "A" will have 'space' set to
// false. Accumulate all of these to recreate the original lexical
// appearing token.
do {
token = scanToken(&pastedPpToken);
// This covers end of argument expansion
if (token == tMarkerInput::marker) {
parseContext.ppError(ppToken.loc, "unexpected location; end of argument", "##", "");
return resultToken;
}
// get the token text
switch (resultToken) {
case PpAtomIdentifier:
// already have the correct text in token.names
break;
case '=':
case '!':
case '-':
case '~':
case '+':
case '*':
case '/':
case '%':
case '<':
case '>':
case '|':
case '^':
case '&':
case PpAtomRight:
case PpAtomLeft:
case PpAtomAnd:
case PpAtomOr:
case PpAtomXor:
snprintf(ppToken.name, sizeof(ppToken.name), "%s", atomStrings.getString(resultToken));
snprintf(pastedPpToken.name, sizeof(pastedPpToken.name), "%s", atomStrings.getString(token));
break;
default:
parseContext.ppError(ppToken.loc, "not supported for these tokens", "##", "");
return resultToken;
}
// combine the tokens
if (strlen(ppToken.name) + strlen(pastedPpToken.name) > MaxTokenLength) {
parseContext.ppError(ppToken.loc, "combined tokens are too long", "##", "");
return resultToken;
}
snprintf(&ppToken.name[0] + strlen(ppToken.name), sizeof(ppToken.name) - strlen(ppToken.name),
"%s", pastedPpToken.name);
// correct the kind of token we are making, if needed (identifiers stay identifiers)
if (resultToken != PpAtomIdentifier) {
int newToken = atomStrings.getAtom(ppToken.name);
if (newToken > 0)
resultToken = newToken;
else
parseContext.ppError(ppToken.loc, "combined token is invalid", "##", "");
}
} while (peekContinuedPasting(resultToken));
}
return resultToken;
}