/* Returns nonzero if a space should be inserted to avoid an
accidental token paste for output. For simplicity, it is
conservative, and occasionally advises a space where one is not
needed, e.g. "." and ".2". */
int
cpp_avoid_paste (cpp_reader *pfile, const cpp_token *token1,
const cpp_token *token2)
{
enum cpp_ttype a = token1->type, b = token2->type;
cppchar_t c;
if (token1->flags & NAMED_OP)
a = CPP_NAME;
if (token2->flags & NAMED_OP)
b = CPP_NAME;
c = EOF;
if (token2->flags & DIGRAPH)
c = digraph_spellings[(int) b - (int) CPP_FIRST_DIGRAPH][0];
else if (token_spellings[b].category == SPELL_OPERATOR)
c = token_spellings[b].name[0];
/* Quickly get everything that can paste with an '='. */
if ((int) a <= (int) CPP_LAST_EQ && c == '=')
return 1;
switch (a)
{
case CPP_GREATER: return c == '>' || c == '?';
case CPP_LESS: return c == '<' || c == '?' || c == '%' || c == ':';
case CPP_PLUS: return c == '+';
case CPP_MINUS: return c == '-' || c == '>';
case CPP_DIV: return c == '/' || c == '*'; /* Comments. */
case CPP_MOD: return c == ':' || c == '>';
case CPP_AND: return c == '&';
case CPP_OR: return c == '|';
case CPP_COLON: return c == ':' || c == '>';
case CPP_DEREF: return c == '*';
case CPP_DOT: return c == '.' || c == '%' || b == CPP_NUMBER;
case CPP_HASH: return c == '#' || c == '%'; /* Digraph form. */
case CPP_NAME: return ((b == CPP_NUMBER
&& name_p (pfile, &token2->val.str))
|| b == CPP_NAME
|| b == CPP_CHAR || b == CPP_STRING); /* L */
case CPP_NUMBER: return (b == CPP_NUMBER || b == CPP_NAME
|| c == '.' || c == '+' || c == '-');
/* UCNs */
case CPP_OTHER: return ((token1->val.str.text[0] == '\\'
&& b == CPP_NAME)
|| (CPP_OPTION (pfile, objc)
&& token1->val.str.text[0] == '@'
&& (b == CPP_NAME || b == CPP_STRING)));
default: break;
}
return 0;
}
static void logo_Lexer_advance(logo_Lexer *self) {
#define opv(_name, _value) do { self->token = (logo_Token) { .type = logo_Token_ ## _name, .value = _value, .start = start, .end = logo_Stream_position(self->stream) }; return; } while (0)
#define op(_name) opv(_name, NULL)
long start = logo_Stream_position(self->stream);
int c = logo_Stream_next(self->stream);
bool whitespace = false;
trim:
if (whitespace_p(c) || ((self->list_level || self->in_proc) && newline_p(c))) {
start = logo_Stream_position(self->stream);
c = logo_Stream_next(self->stream);
whitespace = true;
goto trim;
}
if (c == '#') {
if (logo_Stream_next(self->stream) == '!') {
do {
c = logo_Stream_next(self->stream);
} while (!newline_p(c) && c != logo_Stream_END);
start = logo_Stream_position(self->stream) - 1;
goto trim;
}
logo_Stream_skip(self->stream, -1);
}
if (c == ';' && self->list_level == 0) {
do {
c = logo_Stream_next(self->stream);
} while (!newline_p(c) && c != logo_Stream_END);
start = logo_Stream_position(self->stream) - 1;
goto trim;
}
switch (c) {
case logo_Stream_END:
op(END);
case '[':
++self->list_level;
op(LBRACKET);
case ']':
if (self->list_level > 0) --self->list_level;
op(RBRACKET);
}
if (newline_p(c)) {
do {
c = logo_Stream_next(self->stream);
} while (newline_p(c));
logo_Stream_skip(self->stream, -1);
op(NEWLINE);
}
if (self->list_level || self->in_proc) {
size_t size = 0;
do {
++size;
c = logo_Stream_next(self->stream);
} while (lword_p(c));
logo_Stream_skip(self->stream, -size - 1);
char *s = malloc(size + 1), *p;
for (p = s; p < s + size; ++p) {
*p = logo_Stream_next(self->stream);
}
*p = 0;
if (self->in_proc && strcmp(s, "end") == 0) {
free(s);
op(PROCEND);
}
opv(WORD, s);
}
switch (c) {
case '(': op(LPAREN);
case ')': op(RPAREN);
case ':': op(COLON);
case '?': op(QUESTION);
case '+': op(ADD);
case '-':
if (whitespace && !whitespace_p(logo_Stream_peek(self->stream))) {
op(INVERSE);
}
op(SUB);
case '*': op(MUL);
case '/': op(DIV);
case '=': op(EQUAL);
case '>':
if (logo_Stream_peek(self->stream) == '=') {
logo_Stream_next(self->stream);
op(GTE);
}
op(GT);
case '<':
if (logo_Stream_peek(self->stream) == '=') {
logo_Stream_next(self->stream);
op(LTE);
}
if (logo_Stream_peek(self->stream) == '>') {
logo_Stream_next(self->stream);
op(NOTEQUAL);
}
op(LT);
}
if (c == '"') {
size_t size = 0;
c = logo_Stream_next(self->stream);
while (word_p(c)) {
++size;
c = logo_Stream_next(self->stream);
}
logo_Stream_skip(self->stream, -size - 1);
char *s = malloc(size + 1), *p;
for (p = s; p < s + size; ++p) {
*p = logo_Stream_next(self->stream);
}
*p = 0;
opv(WORD, s);
}
if (digit_p(c)) {
size_t size = 0;
#define next do { ++size; c = logo_Stream_next(self->stream); } while (0)
do {
do next; while (digit_p(c));
if (c == '.') {
next;
if (!digit_p(c)) break;
do next; while (digit_p(c));
}
if (c == 'e' || c == 'E') {
next;
if (c == '+' || c == '-') next;
if (!digit_p(c)) break;
do next; while (digit_p(c));
}
if (name_p(c)) break;
logo_Stream_skip(self->stream, -size - 1);
char *s = malloc(size + 1), *p;
for (p = s; p < s + size; ++p) {
*p = logo_Stream_next(self->stream);
}
*p = 0;
opv(NUMBER, s);
} while (false);
#undef next
logo_Stream_skip(self->stream, -size - 1);
c = logo_Stream_next(self->stream);
}
if (name_p(c)) {
size_t size = 0;
do {
++size;
c = logo_Stream_next(self->stream);
} while (name_p(c));
logo_Stream_skip(self->stream, -size - 1);
char *s = malloc(size), *p;
for (p = s; p < s + size; ++p) {
*p = logo_Stream_next(self->stream);
}
*p = 0;
opv(NAME, s);
}
#undef op
}