int StatementReaderGetNext()

in c/driver/sqlite/statement_reader.c [561:642]
73 lines of code
20 McCabe index (conditional complexity)

int StatementReaderGetNext(struct ArrowArrayStream* self, struct ArrowArray* out) {
  if (!self->release || !self->private_data) {
    return EINVAL;
  }

  struct StatementReader* reader = (struct StatementReader*)self->private_data;
  if (reader->initial_batch.release != NULL) {
    memcpy(out, &reader->initial_batch, sizeof(*out));
    memset(&reader->initial_batch, 0, sizeof(reader->initial_batch));
    return 0;
  } else if (reader->done) {
    out->release = NULL;
    return 0;
  }

  RAISE_NA(ArrowArrayInitFromSchema(out, &reader->schema, &reader->error));
  RAISE_NA(ArrowArrayStartAppending(out));
  int64_t batch_size = 0;
  int status = 0;

  sqlite3_mutex_enter(sqlite3_db_mutex(reader->db));
  while (batch_size < reader->batch_size) {
    int rc = sqlite3_step(reader->stmt);
    if (rc == SQLITE_DONE) {
      if (!reader->binder) {
        reader->done = 1;
        break;
      } else {
        char finished = 0;
        struct AdbcError error = {0};
        status = AdbcSqliteBinderBindNext(reader->binder, reader->db, reader->stmt,
                                          &finished, &error);
        if (status != ADBC_STATUS_OK) {
          reader->done = 1;
          status = EIO;
          if (error.release) {
            strncpy(reader->error.message, error.message, sizeof(reader->error.message));
            reader->error.message[sizeof(reader->error.message) - 1] = '\0';
            error.release(&error);
          }
          break;
        } else if (finished) {
          reader->done = 1;
          break;
        }
        continue;
      }
    } else if (rc == SQLITE_ERROR) {
      reader->done = 1;
      status = EIO;
      StatementReaderSetError(reader);
      break;
    } else if (rc != SQLITE_ROW) {
      reader->done = 1;
      status = ADBC_STATUS_INTERNAL;
      StatementReaderSetError(reader);
      break;
    }

    for (int col = 0; col < reader->schema.n_children; col++) {
      status = StatementReaderGetOneValue(reader, col, out->children[col]);
      if (status != 0) break;
    }

    if (status != 0) break;
    batch_size++;
  }
  if (status == 0) {
    out->length = batch_size;
    for (int i = 0; i < reader->schema.n_children; i++) {
      status = ArrowArrayFinishBuildingDefault(out->children[i], &reader->error);
      if (status != 0) break;
    }

    // If we didn't read any rows, the reader is exhausted - don't generate a spurious
    // batch
    if (batch_size == 0) out->release(out);
  }

  sqlite3_mutex_leave(sqlite3_db_mutex(reader->db));
  return status;
}