forked from OSchip/llvm-project
65 lines
2.2 KiB
ReStructuredText
65 lines
2.2 KiB
ReStructuredText
.. title:: clang-tidy - bugprone-suspicious-string-compare
|
|
|
|
bugprone-suspicious-string-compare
|
|
==================================
|
|
|
|
Find suspicious usage of runtime string comparison functions.
|
|
This check is valid in C and C++.
|
|
|
|
Checks for calls with implicit comparator and proposed to explicitly add it.
|
|
|
|
.. code-block:: c++
|
|
|
|
if (strcmp(...)) // Implicitly compare to zero
|
|
if (!strcmp(...)) // Won't warn
|
|
if (strcmp(...) != 0) // Won't warn
|
|
|
|
Checks that compare function results (i,e, ``strcmp``) are compared to valid
|
|
constant. The resulting value is
|
|
|
|
.. code::
|
|
|
|
< 0 when lower than,
|
|
> 0 when greater than,
|
|
== 0 when equals.
|
|
|
|
A common mistake is to compare the result to `1` or `-1`.
|
|
|
|
.. code-block:: c++
|
|
|
|
if (strcmp(...) == -1) // Incorrect usage of the returned value.
|
|
|
|
Additionally, the check warns if the results value is implicitly cast to a
|
|
*suspicious* non-integer type. It's happening when the returned value is used in
|
|
a wrong context.
|
|
|
|
.. code-block:: c++
|
|
|
|
if (strcmp(...) < 0.) // Incorrect usage of the returned value.
|
|
|
|
Options
|
|
-------
|
|
|
|
.. option:: WarnOnImplicitComparison
|
|
|
|
When `true`, the check will warn on implicit comparison. `true` by default.
|
|
|
|
.. option:: WarnOnLogicalNotComparison
|
|
|
|
When `true`, the check will warn on logical not comparison. `false` by default.
|
|
|
|
.. option:: StringCompareLikeFunctions
|
|
|
|
A string specifying the comma-separated names of the extra string comparison
|
|
functions. Default is an empty string.
|
|
The check will detect the following string comparison functions:
|
|
`__builtin_memcmp`, `__builtin_strcasecmp`, `__builtin_strcmp`,
|
|
`__builtin_strncasecmp`, `__builtin_strncmp`, `_mbscmp`, `_mbscmp_l`,
|
|
`_mbsicmp`, `_mbsicmp_l`, `_mbsnbcmp`, `_mbsnbcmp_l`, `_mbsnbicmp`,
|
|
`_mbsnbicmp_l`, `_mbsncmp`, `_mbsncmp_l`, `_mbsnicmp`, `_mbsnicmp_l`,
|
|
`_memicmp`, `_memicmp_l`, `_stricmp`, `_stricmp_l`, `_strnicmp`,
|
|
`_strnicmp_l`, `_wcsicmp`, `_wcsicmp_l`, `_wcsnicmp`, `_wcsnicmp_l`,
|
|
`lstrcmp`, `lstrcmpi`, `memcmp`, `memicmp`, `strcasecmp`, `strcmp`,
|
|
`strcmpi`, `stricmp`, `strncasecmp`, `strncmp`, `strnicmp`, `wcscasecmp`,
|
|
`wcscmp`, `wcsicmp`, `wcsncmp`, `wcsnicmp`, `wmemcmp`.
|