Python Help with Stack Buffer Overflow

[JimmysNetwork]

Hi all,

I am working on a new project, and I can't seem to get past an issue with getting an error code;
[Done] exited with code=3221226505 in 5.251 seconds

My understanding is;

The exit code 3221226505 corresponds to a stack buffer overrun (also known as a stack buffer overflow), which is a type of memory corruption issue. It indicates that your program attempted to use more stack memory than allocated, potentially overwriting memory that should not have been modified, leading to a crash.

I may be overlooking the issue, as I have been working onthe entire project for hours now. I would appreciate it if anyone here has an idea as to what is causing the software to crash.

import logging
from PyQt5.QtWidgets import (
    QWidget, QLabel, QLineEdit, QPushButton, QVBoxLayout, QHBoxLayout,
    QTableWidget, QTableWidgetItem, QComboBox, QMessageBox, QSizePolicy,
    QSpacerItem
)
from PyQt5.QtCore import Qt
from db import get_connection
from datetime import datetime

# Set up logging to log errors
logging.basicConfig(level=logging.ERROR, filename="app.log", filemode="a", format="%(asctime)s - %(levelname)s - %(message)s")

class PurchaseOrderWindow(QWidget):
    def __init__(self, user_id, stack=None):
        super().__init__()
        self.setWindowTitle("Create Purchase Order")
        self.setGeometry(200, 200, 800, 600)
        self.user_id = user_id
        self.stack = stack
        self.items_data = {}
        self.deleted_rows = []

        self.load_inventory_items()

        layout = QVBoxLayout()
        if self.stack:
            layout.setMenuBar(create_main_menu(self, self.stack, self.user_id))

        layout.addSpacerItem(QSpacerItem(20, 30, QSizePolicy.Minimum, QSizePolicy.Expanding))

        layout.addWidget(QLabel("PO Number"))
        self.po_number_input = QLineEdit()
        self.set_next_po_number()
        layout.addWidget(self.po_number_input)

        layout.addWidget(QLabel("Client"))
        self.client_dropdown = QComboBox()
        self.load_clients()
        layout.addWidget(self.client_dropdown)

        self.date_label = QLabel(f"Date: {datetime.now().strftime('%Y-%m-%d')}")
        self.date_label.setAlignment(Qt.AlignRight)
        self.date_label.setStyleSheet("font-style: italic; color: gray;")
        layout.addWidget(self.date_label)

        layout.addWidget(QLabel("PO Items"))
        self.table = QTableWidget()
        self.table.setColumnCount(4)
        self.table.setHorizontalHeaderLabels(["Item Name", "Quantity", "Unit Price", "Total"])
        self.table.setDragDropMode(QTableWidget.InternalMove)
        self.table.setFocusPolicy(Qt.StrongFocus)
        self.table.keyPressEvent = self.handle_table_keypress
        layout.addWidget(self.table)

        # Dropdown for PO Status (Draft, Open, Confirmed, Completed)
        self.status_label = QLabel("PO Status")
        self.status_dropdown = QComboBox()
        self.status_dropdown.addItems(["Draft", "Open", "Confirmed", "Completed"])
        layout.addWidget(self.status_label)
        layout.addWidget(self.status_dropdown)

        self.total_label = QLabel("Total: $0.00")
        self.total_label.setAlignment(Qt.AlignRight)
        self.total_label.setStyleSheet("font-size: 14px; font-weight: bold;")
        layout.addWidget(self.total_label)

        buttons_layout = QHBoxLayout()
        self.add_row_button = QPushButton("Add Item Row")
        self.add_row_button.clicked.connect(self.add_item_row)
        self.remove_row_button = QPushButton("Remove Selected Row")
        self.remove_row_button.clicked.connect(self.remove_selected_row)
        self.undo_button = QPushButton("Undo Delete")
        self.undo_button.clicked.connect(self.undo_delete)
        self.save_po_button = QPushButton("Save Purchase Order")
        self.save_po_button.clicked.connect(self.save_po)

        buttons_layout.addWidget(self.add_row_button)
        buttons_layout.addWidget(self.remove_row_button)
        buttons_layout.addWidget(self.undo_button)
        buttons_layout.addWidget(self.save_po_button)
        layout.addLayout(buttons_layout)

        layout.addSpacerItem(QSpacerItem(20, 30, QSizePolicy.Minimum, QSizePolicy.Expanding))

        self.setLayout(layout)

    def load_inventory_items(self):
        try:
            conn = get_connection()
            cursor = conn.cursor()
            cursor.execute("SELECT name, quantity, unit_price FROM items")
            for name, qty, price in cursor.fetchall():
                self.items_data[name] = {"quantity": qty, "unit_price": float(price)}
            cursor.close()
            conn.close()
        except Exception as e:
            logging.error(f"Failed to load inventory items: {e}")
            QMessageBox.critical(self, "Error", "Could not load inventory items.")

    def load_clients(self):
        try:
            conn = get_connection()
            cursor = conn.cursor()
            cursor.execute("SELECT id, name FROM clients ORDER BY name")
            for client_id, name in cursor.fetchall():
                self.client_dropdown.addItem(name, client_id)
            cursor.close()
            conn.close()
        except Exception as e:
            logging.error(f"Failed to load clients: {e}")
            QMessageBox.critical(self, "Error", "Could not load clients.")

    def set_next_po_number(self):
        try:
            conn = get_connection()
            cursor = conn.cursor()
            cursor.execute("SELECT MAX(CAST(SUBSTRING(po_number, 4) AS UNSIGNED)) FROM purchase_orders")
            result = cursor.fetchone()
            next_number = (result[0] or 0) + 1
            self.po_number_input.setText(f"PO-{next_number:04d}")
            cursor.close()
            conn.close()
        except Exception as e:
            logging.error(f"Error generating PO number: {e}")
            print("Error generating PO number:", e)

    def save_po(self):
        po_number = self.po_number_input.text()
        client_id = self.client_dropdown.currentIndex()
        status = self.status_dropdown.currentText().lower()

        # Debugging print
        logging.debug(f"PO Number: {po_number}, Client ID: {client_id}, Status: {status}")

        if not po_number or client_id == -1:  # Check for invalid client selection
            QMessageBox.warning(self, "Error", "PO number and client selection are required.")
            return

        items = []
        for row in range(self.table.rowCount()):
            combo = self.table.cellWidget(row, 0)
            qty_input = self.table.cellWidget(row, 1)
            price_item = self.table.item(row, 2)
            if not combo or not qty_input or not price_item:
                continue
            name = combo.currentText()
            try:
                qty = int(qty_input.text())
                price = float(price_item.text())
            except ValueError:
                continue
            if qty <= 0:
                continue
            items.append((name, qty, price))

        if not items:
            QMessageBox.warning(self, "Error", "At least one valid item is required.")
            return

        try:
            conn = get_connection()
            cursor = conn.cursor()

            cursor.execute("SELECT id FROM purchase_orders WHERE po_number = %s", (po_number,))
            if cursor.fetchone():
                QMessageBox.warning(self, "Error", "PO number already exists. Please choose a different one.")
                return

            logging.debug(f"Inserting PO with status: {status}")

            cursor.execute("INSERT INTO purchase_orders (po_number, client_id, created_by, status) VALUES (%s, %s, %s, %s)",
                           (po_number, client_id, self.user_id, status))
            po_id = cursor.lastrowid

            logging.debug(f"Inserted PO with ID: {po_id}")

            for name, qty, price in items:
                cursor.execute(
                    "INSERT INTO po_items (po_id, item_name, quantity, unit_price) VALUES (%s, %s, %s, %s)",
                    (po_id, name, qty, price)
                )
                cursor.execute(
                    "UPDATE items SET quantity = quantity - %s WHERE name = %s",
                    (qty, name)
                )

            conn.commit()
            QMessageBox.information(self, "Success", "Purchase Order saved!")
            if self.stack:
                self.stack.addWidget(POListWindow(stack=self.stack))
                self.stack.setCurrentIndex(self.stack.count() - 1)
            else:
                self.close()

        except Exception as e:
            logging.error(f"Failed to save PO: {e}")
            QMessageBox.critical(self, "Error", f"Failed to save PO: {e}")
            conn.rollback()

        finally:
            cursor.close()
            conn.close()

Thanks in advance!

 

[JimmysNetwork]

I ended up figuring out the issues:

Summary of Fixes:​

Problem	Fix
cellWidget() on empty cells	Call add_item_row() at startup
Missing widgets in table	Added QComboBox, QLineEdit, etc. properly
Unsafe event override	Removed self.table.keyPressEvent = ...
Missing imports	Added create_main_menu and POListWindow