Merge pull request ClickHouse#90035 from ClickHouse/backport/25.8/89929

Backport ClickHouse#89929 to 25.8: Fix buffer size calculation for base32Encode

Author: clickhouse-gh[bot]

src/Functions/FunctionBase32Conversion.h

@@ -11,10 +11,10 @@ struct Base32EncodeTraits
     template <typename Col>
     static size_t getBufferSize(Col const & src_column)
     {
-        auto const src_length = src_column.getChars().size() + src_column.size();
+        auto const src_length = src_column.getChars().size();
         /// Every 5 bytes becomes 8 bytes in base32
         /// Add padding for incomplete blocks and round up
-        return (src_length + 4) / 5 * 8;
+        return ((src_length + src_column.size() * 4) / 5) * 8;
     }
 
     static size_t perform(std::string_view src, UInt8 * dst)
@@ -28,8 +28,7 @@ struct Base32DecodeTraits
     template <typename Col>
     static size_t getBufferSize(Col const & src_column)
     {
-        /// This function can be used for FixedString columns so we need to take into account NULL terminator
-        auto const string_length = src_column.getChars().size() + src_column.size();
+        auto const string_length = src_column.getChars().size();
         /// decoded size is at most length of encoded (every 8 bytes becomes at most 5 bytes)
         return (string_length * 5 + 7) / 8;
     }

src/Functions/FunctionBase58Conversion.h

@@ -29,8 +29,7 @@ struct Base58DecodeTraits
     template <typename Col>
     static size_t getBufferSize(Col const & src_column)
     {
-        /// This function can be used for FixedString columns so we need to take into account NULL terminator
-        auto const string_length = src_column.getChars().size() + src_column.size();
+        auto const string_length = src_column.getChars().size();
         /// decoded size is at most length of encoded (every 8 bytes becomes at most 6 bytes)
         return (string_length * 6 + 7) / 8;
     }

tests/queries/0_stateless/03714_base32_base58_short_string.reference

@@ -0,0 +1,4 @@
+-- Tags: no-fasttest
+
+SELECT base32Encode(randomString(1, 100)) FROM numbers(1000) FORMAT Null;
+SELECT base58Encode(randomString(1, 100)) FROM numbers(1000) FORMAT Null;