GH-61 Place an upper bound on p4StackDump().

SirWumpus · Nov 7, 2024 · 5b85ce7 · 5b85ce7
1 parent c2de43f
commit 5b85ce7
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Showing 2 changed files with 9 additions and 2 deletions.
diff --git a/src/post4.c b/src/post4.c
@@ -378,11 +378,18 @@ p4Nap(P4_Uint seconds, P4_Uint nanoseconds)
 }
 
 void
-p4StackDump(FILE *fp, P4_Cell *base, P4_Uint length)
+p4StackDump(FILE *fp, P4_Cell *base, unsigned length)
 {
 	P4_Cell *cell;
 	unsigned count;
 
+	/* Place an upper bounds on the length of the stack
+	 * to handle a converted signed value or impossibly
+	 * large value being given.
+	 */
+	if (1024 <= length) {
+		length = 1024;
+	}
 	for (count = 0, cell = base; 0 < length--; cell++) {
 		if ((count & 3) == 0) {
 			(void) fprintf(fp, "top-%.2u ", (unsigned) length);

diff --git a/src/post4.p4 b/src/post4.p4
@@ -547,7 +547,7 @@ MAX-U MAX-N 2CONSTANT MAX-D
 \ (C: <spaces>name -- ) (S: -- xt )
 : ['] LIT LIT COMPILE, ' COMPILE, ; IMMEDIATE compile-only
 
-\ (C: x -- ) (S: x -- )
+\ (C: x -- ; S:  -- x )
 : LIT, ['] LIT COMPILE, , ;
 
 \ ... : name ... [ x ] LITERAL ... ;