On Tue, Aug 13, 2024 at 11:16:01 +0300, Valery Ushakov wrote:
> On the second thought at? vs at prevents copy-pasting of config
> chunks, so a form of ifdef that checks instantiation is probably
> better and is pretty trivial to add
>
> ifinstance virtio
> vio9p* at virtio?
> endif
>
> in GENERIC.local makes both GENERIC and XEN* config ok with vio9p
> configured in GENERIC.
The diff (though, without copy-pasted (el)?ifn? variants).
Index: scan.l
===================================================================
RCS file: /cvsroot/src/usr.bin/config/scan.l,v
retrieving revision 1.36
diff -u -p -p -r1.36 scan.l
--- scan.l 13 Aug 2024 10:14:04 -0000 1.36
+++ scan.l 13 Aug 2024 13:57:22 -0000
@@ -116,6 +116,7 @@ static struct incl *incl;
static int endinclude(void);
static int getincludepath(void);
static int getcurifdef(void);
+static int getcurinst(void);
SLIST_HEAD(, prefix) curdirs; /* curdir stack */
@@ -209,6 +210,23 @@ with return WITH;
yyline++;
}
+<*>{WS}ifinstance[ \t]+{WORD}{RESTOFLINE} {
+ ifdefstate <<= IDS_SHIFT;
+ if (++ifdefshift >= IDS_MAX_DEPTH) {
+ yyerror("too many levels of conditional");
+ }
+ IDS_ENTER(ifdef, 0);
+ if (IDS_PARENT_DISABLED || !getcurinst()) {
+ ifdefstate &= (uint64_t)~IDS_ENABLED;
+ BEGIN(IGNORED);
+ } else {
+ ifdefstate |= IDS_MATCH|IDS_ENABLED;
+ BEGIN(INITIAL);
+ }
+ IDS_EXIT(ifdef, 0);
+ yyline++;
+ }
+
<*>{WS}ifndef[ \t]+{WORD}{RESTOFLINE} {
ifdefstate <<= IDS_SHIFT;
if (++ifdefshift >= IDS_MAX_DEPTH) {
@@ -660,3 +678,29 @@ getcurifdef(void)
return ht_lookup(attrtab, intern(p)) != NULL;
}
+
+/*
+ * Get device name that comes after "ifinstance" and variants, check
+ * that it's a known base device that has been selected for
+ * instantiation.
+ */
+static int
+getcurinst(void)
+{
+ char *p = yytext;
+
+ /* skip the "if" keyword and the whitespace after it */
+ while (*p && isascii((unsigned char)*p) && !isspace((unsigned char)*p))
+ p++;
+ while (*p && isascii((unsigned char)*p) && isspace((unsigned char)*p))
+ p++;
+
+ /* device name */
+ const char *name = p;
+ while (*p && isascii((unsigned char)*p) && !isspace((unsigned char)*p))
+ p++;
+ *p = '\0';
+
+ const struct devbase *d = ht_lookup(devbasetab, intern(name));
+ return d != NULL && d->d_ihead != NULL;
+}
-uwe
