// Check string for an identifier or keyword. If found, set *srcpp to first invalid character, set *lenp to word length (if
// lenp not NULL), and return symbol; otherwise, return s_nil.
enum e_sym getident(char **srcpp,ushort *lenp) {
int i;
ushort len;
enum e_sym sym;
char *srcp,*srcp0 = *srcpp;
if(!isident1(*srcp0))
return s_nil;
// Valid identifier found; find terminator.
srcp = srcp0 + strspn(srcp0,identchars);
// Query type?
if(*srcp == TKC_QUERY) {
*srcpp = srcp + 1;
if(lenp != NULL)
*lenp = *srcpp - srcp0;
return s_identq;
}
// Check if keyword.
sym = s_ident;
char idbuf[(len = srcp - srcp0) + 1];
stplcpy(idbuf,srcp0,len + 1);
if((i = binary(idbuf,kwname,NKEYWORDS)) >= 0) {
sym = kwtab[i].s;
if(lenp != NULL)
*lenp = len;
}
// Return results.
*srcpp = srcp;
return sym;
}
void
vcc_Lexer(struct tokenlist *tl, struct source *sp)
{
const char *p, *q;
unsigned u;
tl->src = sp;
for (p = sp->b; p < sp->e; ) {
/* Skip any whitespace */
if (isspace(*p)) {
p++;
continue;
}
/* Skip '#.*\n' comments */
if (*p == '#') {
while (p < sp->e && *p != '\n')
p++;
continue;
}
/* Skip C-style comments */
if (*p == '/' && p[1] == '*') {
for (q = p + 2; q < sp->e; q++) {
if (*q == '/' && q[1] == '*') {
vsb_printf(tl->sb,
"/* ... */ comment contains /*\n");
vcc_AddToken(tl, EOI, p, p + 2);
vcc_ErrWhere(tl, tl->t);
vcc_AddToken(tl, EOI, q, q + 2);
vcc_ErrWhere(tl, tl->t);
return;
}
if (*q == '*' && q[1] == '/') {
p = q + 2;
break;
}
}
if (q < sp->e)
continue;
vcc_AddToken(tl, EOI, p, p + 2);
vsb_printf(tl->sb,
"Unterminated /* ... */ comment, starting at\n");
vcc_ErrWhere(tl, tl->t);
return;
}
/* Skip C++-style comments */
if (*p == '/' && p[1] == '/') {
while (p < sp->e && *p != '\n')
p++;
continue;
}
/* Recognize inline C-code */
if (*p == 'C' && p[1] == '{') {
for (q = p + 2; q < sp->e; q++) {
if (*q == '}' && q[1] == 'C') {
vcc_AddToken(tl, CSRC, p, q + 2);
break;
}
}
if (q < sp->e) {
p = q + 2;
continue;
}
vcc_AddToken(tl, EOI, p, p + 2);
vsb_printf(tl->sb,
"Unterminated inline C source, starting at\n");
vcc_ErrWhere(tl, tl->t);
return;
}
/* Recognize long-strings */
if (*p == '{' && p[1] == '"') {
for (q = p + 2; q < sp->e; q++) {
if (*q == '"' && q[1] == '}') {
vcc_AddToken(tl, CSTR, p, q + 2);
break;
}
}
if (q < sp->e) {
p = q + 2;
u = tl->t->e - tl->t->b;
u -= 4; /* {" ... "} */
tl->t->dec = TlAlloc(tl, u + 1 );
AN(tl->t->dec);
memcpy(tl->t->dec, tl->t->b + 2, u);
tl->t->dec[u] = '\0';
continue;
}
vcc_AddToken(tl, EOI, p, p + 2);
vsb_printf(tl->sb,
"Unterminated long-string, starting at\n");
vcc_ErrWhere(tl, tl->t);
return;
}
/* Match for the fixed tokens (see token.tcl) */
u = vcl_fixed_token(p, &q);
if (u != 0) {
vcc_AddToken(tl, u, p, q);
p = q;
continue;
}
/* Match strings, with \\ and \" escapes */
if (*p == '"') {
for (q = p + 1; q < sp->e; q++) {
if (*q == '"') {
q++;
break;
}
if (*q == '\r' || *q == '\n') {
vcc_AddToken(tl, EOI, p, q);
vsb_printf(tl->sb,
"Unterminated string at\n");
vcc_ErrWhere(tl, tl->t);
return;
}
}
vcc_AddToken(tl, CSTR, p, q);
if (vcc_decstr(tl))
return;
p = q;
continue;
}
/* Match Identifiers */
if (isident1(*p)) {
for (q = p; q < sp->e; q++)
if (!isident(*q))
break;
if (isvar(*q)) {
for (; q < sp->e; q++)
if (!isvar(*q))
break;
vcc_AddToken(tl, VAR, p, q);
} else {
vcc_AddToken(tl, ID, p, q);
}
p = q;
continue;
}
/* Match numbers { [0-9]+ } */
if (isdigit(*p)) {
for (q = p; q < sp->e; q++)
if (!isdigit(*q))
break;
vcc_AddToken(tl, CNUM, p, q);
p = q;
continue;
}
vcc_AddToken(tl, EOI, p, p + 1);
vsb_printf(tl->sb, "Syntax error at\n");
vcc_ErrWhere(tl, tl->t);
return;
}
}
