Basic test, if (no else atm), support with a single statement.

2 files changed, 73 insertions, 40 deletions

diff --git a/usr.sbin/btrace/bt_parse.y b/usr.sbin/btrace/bt_parse.y
index 2a7ac72f38b..9cda3581be6 100644
--- a/usr.sbin/btrace/bt_parse.y
+++ b/usr.sbin/btrace/bt_parse.y
@@ -1,4 +1,4 @@
-/*	$OpenBSD: bt_parse.y,v 1.36 2021/08/31 08:39:26 mpi Exp $	*/
+/*	$OpenBSD: bt_parse.y,v 1.37 2021/08/31 12:51:24 mpi Exp $	*/
 
 /*
  * Copyright (c) 2019-2021 Martin Pieuchot <mpi@openbsd.org>
@@ -115,7 +115,7 @@ static int pflag;
 %token	<v.i>		ERROR ENDFILT
 %token	<v.i>		OP_EQ OP_NE OP_LE OP_LT OP_GE OP_GT OP_LAND OP_LOR
 /* Builtins */
-%token	<v.i>		BUILTIN BEGIN END HZ
+%token	<v.i>		BUILTIN BEGIN END HZ IF
 /* Functions and Map operators */
 %token  <v.i>		F_DELETE F_PRINT FUNC0 FUNC1 FUNCN OP1 OP4 MOP0 MOP1
 %token	<v.string>	STRING CSTRING
@@ -126,7 +126,7 @@ static int pflag;
 %type	<v.i>		beginend
 %type	<v.probe>	probe pname
 %type	<v.filter>	filter
-%type	<v.stmt>	action stmt stmtlist
+%type	<v.stmt>	action stmt stmtblck stmtlist block
 %type	<v.arg>		pat vargs mentry mpat pargs
 %type	<v.arg>		expr term fterm factor
 %%
@@ -239,8 +239,17 @@ stmt	: ';' NL			{ $$ = NULL; }
 	| gvar '=' OP4 '(' pat ',' vargs ')'	{ $$ = bh_inc($1, $5, $7); }
 	;
 
-stmtlist: stmt
+stmtblck: IF '(' expr ')' block			{ $$ = bt_new($3, $5); }
+	;
+
+stmtlist: stmtlist stmtblck		{ $$ = bs_append($1, $2); }
 	| stmtlist stmt			{ $$ = bs_append($1, $2); }
+	| stmtblck
+	| stmt
+	;
+
+block	: '{' stmt ';' '}'			{ $$ = $2; }
+	| stmt ';'
 	;
 
 action	: '{' stmtlist '}'		{ $$ = $2; }
@@ -302,6 +311,17 @@ bc_new(struct bt_arg *term, enum bt_argtype op, struct bt_arg *ba)
 	return bf;
 }
 
+/* Create a new if/else test */
+struct bt_stmt *
+bt_new(struct bt_arg *ba, struct bt_stmt *condbs)
+{
+	struct bt_arg *bop;
+
+	bop = ba_op(B_AT_OP_NE, NULL, ba);
+
+	return bs_new(B_AC_TEST, bop, (struct bt_var *)condbs);
+
+}
 /* Create a new probe */
 struct bt_probe *
 bp_new(const char *prov, const char *func, const char *name, int32_t rate)
@@ -638,6 +658,7 @@ lookup(char *s)
 		{ "exit",	FUNC0,		B_AC_EXIT },
 		{ "hist",	OP1,		0 },
 		{ "hz",		HZ,		0 },
+		{ "if",		IF,		0 },
 		{ "kstack",	BUILTIN,	B_AT_BI_KSTACK },
 		{ "lhist",	OP4,		0 },
 		{ "max",	MOP1,		B_AT_MF_MAX },
diff --git a/usr.sbin/btrace/btrace.c b/usr.sbin/btrace/btrace.c
index 44df20fcb9f..8481601ab8f 100644
--- a/usr.sbin/btrace/btrace.c
+++ b/usr.sbin/btrace/btrace.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: btrace.c,v 1.41 2021/08/31 11:30:21 mpi Exp $ */
+/*	$OpenBSD: btrace.c,v 1.42 2021/08/31 12:51:24 mpi Exp $ */
 
 /*
  * Copyright (c) 2019 - 2020 Martin Pieuchot <mpi@openbsd.org>
@@ -81,6 +81,7 @@ void			 rule_printmaps(struct bt_rule *);
 uint64_t		 builtin_nsecs(struct dt_evt *);
 const char		*builtin_kstack(struct dt_evt *);
 const char		*builtin_arg(struct dt_evt *, enum bt_argtype);
+void			 stmt_eval(struct bt_stmt *, struct dt_evt *);
 void			 stmt_bucketize(struct bt_stmt *, struct dt_evt *);
 void			 stmt_clear(struct bt_stmt *);
 void			 stmt_delete(struct bt_stmt *, struct dt_evt *);
@@ -545,40 +546,10 @@ rule_eval(struct bt_rule *r, struct dt_evt *dtev)
 	}
 
 	SLIST_FOREACH(bs, &r->br_action, bs_next) {
-		switch (bs->bs_act) {
-		case B_AC_BUCKETIZE:
-			stmt_bucketize(bs, dtev);
-			break;
-		case B_AC_CLEAR:
-			stmt_clear(bs);
-			break;
-		case B_AC_DELETE:
-			stmt_delete(bs, dtev);
-			break;
-		case B_AC_EXIT:
-			exit(0);
-			break;
-		case B_AC_INSERT:
-			stmt_insert(bs, dtev);
-			break;
-		case B_AC_PRINT:
-			stmt_print(bs, dtev);
-			break;
-		case B_AC_PRINTF:
-			stmt_printf(bs, dtev);
-			break;
-		case B_AC_STORE:
-			stmt_store(bs, dtev);
-			break;
-		case B_AC_TIME:
-			stmt_time(bs, dtev);
-			break;
-		case B_AC_ZERO:
-			stmt_zero(bs);
-			break;
-		default:
-			xabort("no handler for action type %d", bs->bs_act);
-		}
+		if ((bs->bs_act == B_AC_TEST) && stmt_test(bs, dtev) == true)
+			stmt_eval((struct bt_stmt *)bs->bs_var, dtev);
+
+		stmt_eval(bs, dtev);
 	}
 }
 
@@ -689,6 +660,48 @@ builtin_arg(struct dt_evt *dtev, enum bt_argtype dat)
 	return buf;
 }
 
+void
+stmt_eval(struct bt_stmt *bs, struct dt_evt *dtev)
+{
+	switch (bs->bs_act) {
+	case B_AC_BUCKETIZE:
+		stmt_bucketize(bs, dtev);
+		break;
+	case B_AC_CLEAR:
+		stmt_clear(bs);
+		break;
+	case B_AC_DELETE:
+		stmt_delete(bs, dtev);
+		break;
+	case B_AC_EXIT:
+		exit(0);
+		break;
+	case B_AC_INSERT:
+		stmt_insert(bs, dtev);
+		break;
+	case B_AC_PRINT:
+		stmt_print(bs, dtev);
+		break;
+	case B_AC_PRINTF:
+		stmt_printf(bs, dtev);
+		break;
+	case B_AC_STORE:
+		stmt_store(bs, dtev);
+		break;
+	case B_AC_TEST:
+		/* done before */
+		break;
+	case B_AC_TIME:
+		stmt_time(bs, dtev);
+		break;
+	case B_AC_ZERO:
+		stmt_zero(bs);
+		break;
+	default:
+		xabort("no handler for action type %d", bs->bs_act);
+	}
+}
+
 /*
  * Increment a bucket:	{ @h = hist(v); } or { @h = lhist(v, min, max, step); }
  *
@@ -885,7 +898,6 @@ stmt_test(struct bt_stmt *bs, struct dt_evt *dtev)
 	if (bs == NULL)
 		return true;
 
-	assert(bs->bs_var == NULL);
 	ba = SLIST_FIRST(&bs->bs_args);
 
 	return baexpr2long(ba, dtev) != 0;