Word *
varsub(char **s)
{
Bufblock *b;
Word *w;
if(**s == '{') /* either ${name} or ${name: A%B==C%D}*/
return expandvar(s);
b = varname(s);
if(b == 0)
return 0;
w = varmatch(b->start, s);
freebuf(b);
return w;
}
static Word*
expandvar(char **s)
{
Word *w;
Bufblock *buf;
Symtab *sym;
char *cp, *begin, *end;
begin = *s;
(*s)++; /* skip the '{' */
buf = varname(s);
if (buf == 0)
return 0;
cp = *s;
if (*cp == '}') { /* ${name} variant*/
(*s)++; /* skip the '}' */
w = varmatch(buf->start, s);
freebuf(buf);
return w;
}
if (*cp != ':') {
SYNERR(-1);
fprint(2, "bad variable name <%s>\n", buf->start);
freebuf(buf);
return 0;
}
cp++;
end = charin(cp , "}");
if(end == 0){
SYNERR(-1);
fprint(2, "missing '}': %s\n", begin);
Exit();
}
*end = 0;
*s = end+1;
sym = symlook(buf->start, S_VAR, 0);
if(sym == 0 || sym->value == 0)
w = newword(buf->start);
else
w = subsub((Word*) sym->value, cp, end);
freebuf(buf);
return w;
}
static char *
scan4var( /* scan for variable from fp */
char *buf,
int buflen,
char *vname,
FILE *fp
)
{
int cval;
register char *cp;
/* search out matching line */
while ((cval = varmatch(buf, vname))) {
if (cval > 0) /* gone too far? */
return(NULL);
buf[0] = '\0'; /* else get next line */
if (fgetline(buf, buflen, fp) == NULL)
return(NULL);
}
/* skip variable name and '=' */
for (cp = buf; *cp++ != '='; )
;
while (isspace(*cp)) cp++;
return(cp);
}
