Complete browser OTA responses before reboot and allow HTTP restarts

scripts/esp32_async_web_fix.py

@@ -0,0 +1,53 @@
+"""Build private AsyncTCP fixes and the current vendored OTA implementation."""
+import hashlib
+from pathlib import Path
+
+
+PINNED_ASYNCTCP_SHA256 = "27e3e22a6030cc5c9c9f32f28d0a3a36189b1ea6a5fa270777b2d2790a89c365"
+ORIGINAL_BIND = "  msg->err = tcp_bind(pcb, msg->bind.addr, msg->bind.port);"
+REUSABLE_BIND = """  // A stopped HTTP listener may still have completed connections in
+  // TIME_WAIT. Permit immediate rebinding during WebConfig/OTA handoffs.
+#if SO_REUSE
+  ip_set_option(pcb, SOF_REUSEADDR);
+#endif
+""" + ORIGINAL_BIND
+
+
+def patched_async_tcp(source):
+    source = source.replace("\r\n", "\n")
+    if (hashlib.sha256(source.encode("ascii")).hexdigest() != PINNED_ASYNCTCP_SHA256
+            or source.count(ORIGINAL_BIND) != 1):
+        raise RuntimeError("AsyncTCP restart fix: changed pinned source; review library update")
+    return source.replace(ORIGINAL_BIND, REUSABLE_BIND, 1)
+
+
+def replace_async_source(build_env, node):
+    source = Path(node.srcnode().get_abspath())
+    if source.name == "AsyncTCP.cpp":
+        content = patched_async_tcp(source.read_text(encoding="utf-8"))
+        include_dir = source.parent
+    elif source.name == "AsyncElegantOTA.cpp":
+        # file:// dependencies can retain an earlier copy in .pio/libdeps.
+        # Compile this checkout's vendored source without editing that cache.
+        include_dir = Path(build_env.subst("$PROJECT_DIR")) / "arch/esp32/AsyncElegantOTA/src"
+        content = (include_dir / source.name).read_text(encoding="ascii")
+    else:
+        return node
+    destination = Path(build_env.subst("$BUILD_DIR")) / "patched-esp32-web" / source.name
+    destination.parent.mkdir(parents=True, exist_ok=True)
+    if not destination.exists() or destination.read_text(encoding="ascii") != content:
+        destination.write_text(content, encoding="ascii")
+    build_env.PrependUnique(CPPPATH=[str(include_dir)])
+    return build_env.File(str(destination))
+
+
+def install(build_env):
+    build_env.PrependUnique(CPPPATH=[str(Path(build_env.subst("$PROJECT_DIR"))
+        / "arch/esp32/AsyncElegantOTA/src")])
+    build_env.AddBuildMiddleware(replace_async_source, "*AsyncTCP*src*AsyncTCP.cpp")
+    build_env.AddBuildMiddleware(replace_async_source, "*AsyncElegantOTA*src*AsyncElegantOTA.cpp")
+
+
+if "Import" in globals():
+    Import("env")
+    install(env)