pysss_murmur: Fix warning Wsign-compare

src/python/pysss_murmur.c: In function ‘py_murmurhash3’:
src/python/pysss_murmur.c:47:17: error: comparison between
     signed and unsigned integer expressions [-Werror=sign-compare]
         key_len > strlen(key)) {
                 ^

uint32_t murmurhash3(const char *key, int len, uint32_t seed)
The second argument of the function murmurhash3 has type int.
But the code expects to be unsigned integer.

There is code in python wrapper py_murmurhash3
which check boundaries of that argument.
It should be an unsigned "key_len > INT_MAX || key_len < 0".
An exception should be thrown for negative number.

Moreover, the length should be shorter then a length of input string.
The strlen returns size_t which is unsigned and key_len is signed long.
We already checked that value is unsigned so
we can safely cast key_len to size_t

Reviewed-by: Jakub Hrozek <jhrozek@redhat.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/src/python/pysss_murmur.c b/src/python/pysss_murmur.c
index 97d752b2a..b14a67202 100644
--- a/src/python/pysss_murmur.c
+++ b/src/python/pysss_murmur.c
@@ -44,7 +44,7 @@ static PyObject * py_murmurhash3(PyObject *module, PyObject *args)
     }
 
     if (seed > UINT32_MAX || key_len > INT_MAX || key_len < 0 ||
-        key_len > strlen(key)) {
+        (size_t)key_len > strlen(key)) {
         PyErr_Format(PyExc_ValueError, "Invalid value\n");
         return NULL;
     }