cbor.h: Add explicit casts to conversions from uint64_t to size_t

User code might have stronger warning settings than the ones we've used
so far. The explict casting will make the compiler not complain, as it
was clearly intentional.

This fixes #45.

Signed-off-by: Thiago Macieira <[email protected]>

Author: thiagomacieira

src/cbor.h

@@ -361,7 +361,7 @@ CBOR_INLINE_API CborError cbor_value_get_string_length(const CborValue *value, s
     if (!cbor_value_is_length_known(value))
         return CborErrorUnknownLength;
     uint64_t v = _cbor_value_extract_int64_helper(value);
-    *length = v;
+    *length = (size_t)v;
     if (*length != v)
         return CborErrorDataTooLarge;
     return CborNoError;
@@ -416,7 +416,7 @@ CBOR_INLINE_API CborError cbor_value_get_array_length(const CborValue *value, si
     if (!cbor_value_is_length_known(value))
         return CborErrorUnknownLength;
     uint64_t v = _cbor_value_extract_int64_helper(value);
-    *length = v;
+    *length = (size_t)v;
     if (*length != v)
         return CborErrorDataTooLarge;
     return CborNoError;
@@ -428,7 +428,7 @@ CBOR_INLINE_API CborError cbor_value_get_map_length(const CborValue *value, size
     if (!cbor_value_is_length_known(value))
         return CborErrorUnknownLength;
     uint64_t v = _cbor_value_extract_int64_helper(value);
-    *length = v;
+    *length = (size_t)v;
     if (*length != v)
         return CborErrorDataTooLarge;
     return CborNoError;