1 files changed, 57 insertions, 0 deletions
diff --git a/usr.bin/xlint/lint1/msg_357.c b/usr.bin/xlint/lint1/msg_357.c
new file mode 100644
index 000000000000..e8f4d269076d
--- /dev/null
+++ b/usr.bin/xlint/lint1/msg_357.c
@@ -0,0 +1,57 @@
+/*	$NetBSD: msg_357.c,v 1.3 2024/11/05 06:23:04 rillig Exp $	*/
+# 3 "msg_357.c"
+
+// Test for message: hex escape '%.*s' mixes uppercase and lowercase digits [357]
+
+/*
+ * In the format argument of the snprintb and snprintb_m functions, a bit
+ * position or field width is written as an octal or hexadecimal escape
+ * sequence.  If the description that follows a hexadecimal escape sequence
+ * starts with hexadecimal digits (A-Fa-f), these digits are still part of the
+ * escape sequence instead of the description.
+ *
+ * Since the escape sequences are typically written in lowercase and the
+ * descriptions are typically written in uppercase, a mixture of both cases
+ * indicates a mismatch.
+ */
+
+/* lint1-extra-flags: -X 351 */
+
+typedef typeof(sizeof(0)) size_t;
+typedef unsigned long long uint64_t;
+
+int snprintb(char *, size_t, const char *, uint64_t);
+
+void
+examples(unsigned u32, uint64_t u64)
+{
+	char buf[64];
+
+	/* expect+5: warning: hex escape '\x0aB' mixes uppercase and lowercase digits [357] */
+	/* expect+4: warning: hex escape '\x0aB' has more than 2 digits [358] */
+	/* expect+3: warning: bit position '\x0aB' (171) in '\x0aBIT' out of range 1..32 [371] */
+	snprintb(buf, sizeof(buf),
+	    "\020\x0aBIT",
+	    u32);
+
+	// This mismatch goes undetected as it has only 2 digits, does not mix
+	// case and is in bounds.  A spellchecker could mark the unknown word
+	// 'ield' to give a hint.
+	snprintb(buf, sizeof(buf),
+	    "\020\x1FIELD",
+	    u32);
+
+	// If the input value is restricted further, the unintended hexadecimal
+	// escape sequence is detected, although with a less obvious message.
+	/* expect+3: warning: conversion '\x1FIELD' is unreachable by input value [378] */
+	snprintb(buf, sizeof(buf),
+	    "\020\x1FIELD",
+	    u32 & 0xffff);
+
+	/* expect+5: warning: hex escape '\x0aB' mixes uppercase and lowercase digits [357] */
+	/* expect+4: warning: hex escape '\x0aB' has more than 2 digits [358] */
+	/* expect+3: warning: bit position '\x0aB' (171) in 'b\x0aBIT\0' out of range 0..63 [371] */
+	snprintb(buf, sizeof(buf),
+	    "\177\020b\x0aBIT\0",
+	    u64);
+}