Correct handling of case when the number of batch errors exceeds 65535

(#262).

Author: anthony-tuininga

doc/src/release_notes.rst

@@ -68,6 +68,12 @@ Common Changes
     database
     (`issue 99 <https://github.com/oracle/python-oracledb/issues/99>`__).
 #)  Fixed bug with getting unknown attributes from DbObject instances.
+#)  Error ``DPY-4029: errors in array DML exceed 65535`` is now raised when the
+    number of batch errors exceeds 65535 when calling
+    :meth:`Cursor.executemany()` with the parameter ``batcherrors`` set to the
+    value ``True``. Note that in thick mode this error is not raised unless the
+    number of batch errors is a multiple of 65536; instead, the number of batch
+    errors returned is modulo 65536.
 #)  Errors that have entries in the
     :ref:`troubleshooting documentation <troubleshooting>` now have links to
     that documentation included in the message text.

src/oracledb/errors.py

@@ -269,6 +269,7 @@ def _raise_from_string(exc_type: Exception, message: str) -> None:
 ERR_TNS_NAMES_FILE_MISSING = 4026
 ERR_NO_CONFIG_DIR = 4027
 ERR_INVALID_SERVER_TYPE = 4028
+ERR_TOO_MANY_BATCH_ERRORS = 4029
 
 # error numbers that result in InternalError
 ERR_MESSAGE_TYPE_UNKNOWN = 5000
@@ -308,6 +309,7 @@ def _raise_from_string(exc_type: Exception, message: str) -> None:
     24459: ERR_POOL_NO_CONNECTION_AVAILABLE,
     24496: ERR_POOL_NO_CONNECTION_AVAILABLE,
     24338: ERR_INVALID_REF_CURSOR,
+    38902: ERR_TOO_MANY_BATCH_ERRORS,
 }
 
 # ODPI-C error number cross reference
@@ -553,6 +555,9 @@ def _raise_from_string(exc_type: Exception, message: str) -> None:
     ERR_TOO_MANY_CURSORS_TO_CLOSE: (
         "internal error: attempt to close more than {num_cursors} cursors"
     ),
+    ERR_TOO_MANY_BATCH_ERRORS: (
+        "the number of batch errors from executemany() exceeds 65535"
+    ),
     ERR_UNEXPECTED_DATA: "unexpected data received: {data}",
     ERR_UNEXPECTED_END_OF_DATA: (
         "unexpected end of data: want {num_bytes_wanted} bytes but "

src/oracledb/impl/thin/messages.pyx

@@ -90,9 +90,9 @@ cdef class Message:
 
     cdef int _process_error_info(self, ReadBuffer buf) except -1:
         cdef:
+            uint32_t num_bytes, i, offset, num_offsets
             _OracleErrorInfo info = self.error_info
-            uint16_t num_entries, error_code
-            uint32_t num_bytes, i, offset
+            uint16_t temp16, num_errors, error_code
             uint8_t first_byte
             int16_t error_pos
             str error_msg
@@ -122,11 +122,11 @@ cdef class Message:
         self.processed_error = True
 
         # batch error codes
-        buf.read_ub2(&num_entries)          # batch error codes array
-        if num_entries > 0:
+        buf.read_ub2(&num_errors)           # batch error codes array
+        if num_errors > 0:
             info.batcherrors = []
             buf.read_ub1(&first_byte)
-            for i in range(num_entries):
+            for i in range(num_errors):
                 if first_byte == TNS_LONG_LENGTH_INDICATOR:
                     buf.skip_ub4()          # chunk length ignored
                 buf.read_ub2(&error_code)
@@ -135,22 +135,25 @@ cdef class Message:
                 buf.skip_raw_bytes(1)       # ignore end marker
 
         # batch error offsets
-        buf.read_ub2(&num_entries)          # batch error row offset array
-        if num_entries > 0:
+        buf.read_ub4(&num_offsets)          # batch error row offset array
+        if num_offsets > 0:
+            if num_offsets > 65535:
+                errors._raise_err(errors.ERR_TOO_MANY_BATCH_ERRORS)
             buf.read_ub1(&first_byte)
-            for i in range(num_entries):
+            for i in range(num_offsets):
                 if first_byte == TNS_LONG_LENGTH_INDICATOR:
                     buf.skip_ub4()          # chunk length ignored
                 buf.read_ub4(&offset)
-                info.batcherrors[i].offset = offset
+                if i < num_errors:
+                    info.batcherrors[i].offset = offset
             if first_byte == TNS_LONG_LENGTH_INDICATOR:
                 buf.skip_raw_bytes(1)       # ignore end marker
 
         # batch error messages
-        buf.read_ub2(&num_entries)          # batch error messages array
-        if num_entries > 0:
+        buf.read_ub2(&temp16)               # batch error messages array
+        if temp16 > 0:
             buf.skip_raw_bytes(1)           # ignore packed size
-            for i in range(num_entries):
+            for i in range(temp16):
                 buf.skip_ub2()              # skip chunk length
                 info.batcherrors[i].message = \
                         buf.read_str(TNS_CS_IMPLICIT).rstrip()