bugprone-string-literal-with-embedded-nul¶
Finds occurrences of string literal with embedded NUL character and validates their usage.
Invalid escaping¶
Special characters can be escaped within a string literal by using their
hexadecimal encoding like \x42
. A common mistake is to escape them
like this \0x42
where the \0
stands for the NUL character.
const char* Example[] = "Invalid character: \0x12 should be \x12";
const char* Bytes[] = "\x03\0x02\0x01\0x00\0xFF\0xFF\0xFF";
Truncated literal¶
String-like classes can manipulate strings with embedded NUL as they are keeping
track of the bytes and the length. This is not the case for a char*
(NUL-terminated) string.
A common mistake is to pass a string-literal with embedded NUL to a string constructor expecting a NUL-terminated string. The bytes after the first NUL character are truncated.
std::string str("abc\0def"); // "def" is truncated
str += "\0"; // This statement is doing nothing
if (str == "\0abc") return; // This expression is always true