Raise meaningful error when maximum size of a direct path load is exceeded.

Author: anthony-tuininga

src/oracledb/errors.py

@@ -373,6 +373,7 @@ def _raise_not_supported(feature: str) -> None:
 ERR_INVALID_INTEGER = 4038
 ERR_CANNOT_CONVERT_TO_ARROW_FLOAT = 4039
 ERR_ARROW_FIXED_SIZE_BINARY_VIOLATED = 4040
+ERR_DPL_TOO_MUCH_DATA = 4041
 
 # error numbers that result in InternalError
 ERR_MESSAGE_TYPE_UNKNOWN = 5000
@@ -650,6 +651,9 @@ def _raise_not_supported(feature: str) -> None:
         'the bind variable placeholder ":{name}" cannot be used both before '
         "and after the RETURNING clause in a DML RETURNING statement"
     ),
+    ERR_DPL_TOO_MUCH_DATA: (
+        "the maximum size of a Direct Path load has been exceeded"
+    ),
     ERR_DUPLICATED_PARAMETER: (
         '"{deprecated_name}" and "{new_name}" cannot be specified together'
     ),

src/oracledb/impl/thin/constants.pxi

@@ -625,6 +625,7 @@ cdef enum:
 
 # other direct path load stream constants
 cdef enum:
+    TNS_DPLS_MAX_MESSAGE_SIZE = 1_073_728_895
     TNS_DPLS_MAX_SHORT_LENGTH = 0xfa
     TNS_DPLS_MAX_PIECE_SIZE = 0xfff0
     TNS_DPLS_FAST_HEADER_SIZE = 4

src/oracledb/impl/thin/messages/direct_path_load_stream.pyx

@@ -40,7 +40,7 @@ cdef class DirectPathPiece:
         bint is_split_with_next
         uint8_t flags
         uint8_t num_segments
-        uint32_t length
+        ssize_t length
         bytes data
 
     cdef int finalize(self, PieceBuffer buf) except -1:
@@ -62,11 +62,11 @@ cdef class DirectPathPiece:
             self.flags |= TNS_DPLS_ROW_HEADER_FAST_ROW
             self.flags |= TNS_DPLS_ROW_HEADER_FAST_PIECE
 
-    cdef uint32_t header_length(self):
+    cdef uint8_t header_length(self):
         """
         Returns the length of the piece header.
         """
-        cdef uint32_t length = 2
+        cdef uint8_t length = 2
         if self.is_fast_row():
             length += 2
         return length
@@ -101,10 +101,14 @@ cdef class PieceBuffer(Buffer):
         Finalizes the piece by adding the data in the buffer and calculating
         the piece length, then resetting the buffer.
         """
+        cdef uint64_t new_length
         self.current_piece.finalize(self)
         self.pieces.append(self.current_piece)
-        self.total_piece_length += \
+        new_length = (<uint64_t> self.total_piece_length) + \
                 self.current_piece.length + self.current_piece.header_length()
+        if new_length > TNS_DPLS_MAX_MESSAGE_SIZE:
+            errors._raise_err(errors.ERR_DPL_TOO_MUCH_DATA)
+        self.total_piece_length = <uint32_t> new_length
 
     cdef int _write_more_data(self, ssize_t num_bytes_available,
                               ssize_t num_bytes_wanted) except -1: