Bring more compatibility with native sockets

[Neradoc]

This PR adds methods to socketpool and socket to make it more compatible with the native socketpool and sockets. This was specifically made to make it work with adafruit_httpserver, which it does, once the httpserver library is changed to not import ssl unconditionally.

A breaking change was made to the socket's settimeout(), by copying the core API, which also matches the python API: None blocks, 0 doesn't. Previously this library did the opposite. I don't know what code out there is impacted by this. Maybe this should be investigated a bit before validating the PR.

https://docs.python.org/3/library/socket.html#socket.socket.settimeout
https://docs.circuitpython.org/en/latest/shared-bindings/socketpool/index.html#socketpool.Socket.settimeout

Added missing methods from Socket:

• bind just saves the address/port parameter
• listen uses the ninafw start_server()
• accept gets a client socket from the server (if any)
• setblocking is a shortcut for settimeout() with the appropriate values (True -> None, False -> 0)
• setsockopt currently does nothing

Changes to Socketpool/Socket and ESP_SPIcontrol:

• re-add the socknum argument to the Socket() constructor. It's not in the python socket API, but we need to be able to wrap a Socket object around a socket number returned by ninafw when getting a client connection to the server.
• ESP_SPIcontrol.socket_write returns the number of bytes written, so that:
• Socket.send now returns the number of bytes written (as does sendto) to match the python socket() API.
• SOL_SOCKET and SO_REUSEADDR have been added to SocketPool.

The PR was tested on a Matrix Portal M4 with a modified version of adafruit_httpserver.

[Neradoc]

Here is an example on Matrix Portal M4 that doesn't need external files

# SPDX-FileCopyrightText: Copyright 2025 Neradoc, https://neradoc.me
# SPDX-License-Identifier: MIT
import asyncio
import board
import displayio
import gc
import keypad
import time
import os
import vectorio
from adafruit_httpserver import Server, Response, MIMETypes

PORT = 80

############################################################################
# Matrix
############################################################################

from adafruit_matrixportal.matrix import Matrix

matrix = Matrix(rotation=0)
display = matrix.display
splash = displayio.Group()
display.root_group = splash

color_palette = displayio.Palette(8)
color_palette[0] = 0
color_palette[1] = 0xFFFFFF
color_palette[2] = 0xE40303
color_palette[3] = 0xFF8C00
color_palette[4] = 0xFFED00
color_palette[5] = 0x008026
color_palette[6] = 0x004CFF
color_palette[7] = 0x732982

rectangle = vectorio.Rectangle(
    pixel_shader=color_palette, color_index=1,
    x=display.width//2 - 4, y=display.height//2 - 4,
    width=8, height=8, 
)
splash.append(rectangle)

############################################################################
# modes
############################################################################

class Box:
    def __init__(self, value):
        self.value = value

current_color = Box(1)

def set_color():
    current_color.value = current_color.value % len(color_palette)
    rectangle.color_index = current_color.value

############################################################################
# wifi
############################################################################
gc.collect()

import busio
from digitalio import *
from adafruit_esp32spi import adafruit_esp32spi
import adafruit_esp32spi.adafruit_esp32spi_socketpool as socketpool

def setup_wifi():
    esp32_cs = DigitalInOut(board.ESP_CS)
    esp32_ready = DigitalInOut(board.ESP_BUSY)
    esp32_reset = DigitalInOut(board.ESP_RESET)

    spi = busio.SPI(board.SCK, board.MOSI, board.MISO)
    esp = adafruit_esp32spi.ESP_SPIcontrol(
        spi, esp32_cs, esp32_ready, esp32_reset
    )

    esp.connect_AP(
        os.getenv("WIFI_SSID"),
        os.getenv("WIFI_PASSWORD"),
    )
    esp.set_hostname("microphone")

    return esp

esp = setup_wifi()
server = Server(socketpool.SocketPool(esp))
IP_ADDRESS = "%d.%d.%d.%d" % tuple(esp.ip_address)

############################################################################
# server routes and app logic
############################################################################
gc.collect()

index_page_html = """<body style="background:black; color:white;">"""
for index, color in enumerate(color_palette):
    index_page_html += f"""<p><a style="text-decoration:none; color:white;" href="/color/{index}">Color {index} <span style="border:1px solid grey; background:#{color:06X}"> &nbsp;&nbsp;&nbsp; </span></a></p>"""
index_page_html += """</body>"""

@server.route("/color/get")
def status_get(request):
    # respond with status
    color = color_palette[current_color.value]
    return Response(request, f"#{color:06X}")

@server.route("/color/<index>")
def status_set(request, index):
    try:
        status = int(index)
        current_color.value = status
        set_color()
    except ValueError:
        return Response(request, "Bad Color")
    gc.collect()
    return Response(request, index_page_html, content_type="text/html")

@server.route("/")
def index(request):
    return Response(request, index_page_html, content_type="text/html")

############################################################################
# start and loop
############################################################################

async def main():
    print(f"Started server on http://{IP_ADDRESS}:{PORT}/")
    server.start(host=str(IP_ADDRESS), port=PORT)
    errors_remaining = 5
    while True:
        try:
            server.poll()
            gc.collect()
        except (TimeoutError, ConnectionError) as e:
            # reload if multiple timeouts
            if isinstance(e, TimeoutError):
                errors_remaining -= 1
                if errors_remaining == 0:
                    import supervisor
                    supervisor.reload()
            time.sleep(1)
        await asyncio.sleep(0.01)

asyncio.run(main())

[justmobilize]

We should also see if this fixes/works with: adafruit/Adafruit_CircuitPython_WSGI#21

[justmobilize]

I'll add comments tomorrow, I had gone down a different path for passing the socket number to the socket, to keep things matching across the board

[justmobilize]

We should also potentially wait until the final firmware comes out, since it may have benefits...