Api for saving heap when Client class is used by a Server (WiFiServer class): Client = Server.available().
Suppose the local end is the server and the remote end is the client, we will deal with heap memory at the local end.
When the local application (server) decides to close an active connection with a remote end it issues an Client.stop.
The stop() function calls the close() function of ClientContext class which in turn calls tcp_close.
The connexion is closed by tcp_close and the protocol control block (pcb) can be put in the following states depending on the requests sent by the remote: CLOSING, FIN_WAIT_1 and FIN_WAIT_2. In theses states pcbs are not freed, then consume some memory heap.
If an acknowledgment from the remote end is received, the pcb enter in TIME_WAIT state for some minutes but pcbs in TIME_WAIT state are not freed. Then consume some heap memory.
TIME_WAIT pcbs are automatically freed after some minutes or can be freed for instance issuing an tcp_kill_timewait()
in the local application which will free the oldest pcb in TIME_WAIT state.
If the connection is first closed from the remote end (the client), the local end (server) receive a connection termination request. It then acknowledge it and enter in CLOSE_WAIT state waiting for a connection termination request from the local application.
It then send a termination request and enter in LAST_ACK state until it receive an acknowledgment from the remote end.
After receiving the acknowledgment it enter in ClOSED state and the local pcb is freed leaving some room in the heap memory.
To summarize, when a connexion termination request is send by one end (remote or local), the local pcb is not freed immediatly.
This pcb can be in the following states: FIN_WAIT_1, FIN_WAIT_2, CLOSING, TIME_WAIT, CLOSE_WAIT, LAST_ACK.
As a consequence, some old pcbs from old closed connections are still consuming heap memory.
The local application can call tcp_kill_timewait hoping it will free some TIME_WAIT state pcbs. But if the server receive frequent connections requests and close them after sending whatever it has to send, there may be zero pcbs in TIME_WAIT state among all previously closed connections.
In case of insufficient memory to accept a new connection, lwip has developped a strategy: it successively tries to kill the oldest pcb in TIME_WAIT state, or in LAST_ACK state or in CLOSING state or the oldest active connection with lower priority than the new one.
As a matter of fact this "urgent" strategy is deployed only when very few heap memory remain available (less than some kb). In case of success, Client.available returns a valid Client but the local application will crash when sending or receiving data from the client (Client.read ou readuntil or available) because this need more heap memory and just some kb were freed in lwip to allocate the new pcb structure ans start the new connection.
The propose API is intended to avoid this drawback by calling the abort function of ClientContext which in turn calls tcp_abort which calls tcp_abandon. The connection is aborted and notified to the client with a RESET and the pcb and ressources associated are immediately released increasing the available heap memory.
* WiFiServer - 'rename' available() to accept()
* use server.accept() instead of available()
* WiFiServer.accept() and ArduinoWiFiServer class doc update
* ESP8266WebServer - drop current HC_WAIT_READ connection sooner when another has data
Safari sometimes opens two connections when loading a page and only
sends a request over the second one, resulting in a 5 second wait
(HTTP_MAX_DATA_WAIT) before the request is processed. This commit
drops the current connection after 30ms (HTTP_MAX_DATA_AVAILABLE_WAIT)
when there is a new connection with data available or the buffer of
pending TCP clients is full (currently 5).
* wifi: remove pseudo-modes for shutdown
make shutdown and resumeFromShutdown public
removes extra code from the mode handler and include method description
in the docs
* typo
* dup
* typos
* reference only shutdown() & resumeFromShutdown()
prefer to have some specific function, don't simply chain into sleep
update examples and docs
* safeguard raw sdk config usage
* Disable WiFi at boot by default
* +define WIFI_IS_OFF_AT_BOOT
* remove now useless example
* mv enableWiFiAtBootTime() to core_esp8266_features.h
* sync with master
* per @earlephilhower review: a file was missing
* doc
* WiFi persistence is now false by default
* fix doc
* ditto
* doc: remove sphinx warnings (fix links and formatting)
* fix link name
* fix doc
* legacy: restore persistence
* undeprecate preinit()
* move force modem up to when mode has changed (per @mcspr review)
* do not wake up from sleep when mode if OFF
* fix doc per review
* Add setSSLVersion call to SSL object
Allow users to only allow specific TLS versions for connections with an
additional call in their app, similar to the setCiphers call.
Fixes#7918
* Add SSL level options to WiFiServerSecure
Improve resume speed by passing in last known BSSID
Provide a simpler example for WIFI_SHUTDOWN/WIFI_RESUME
Add documentation for WIFI_SHUTDOWN and WIFI_RESUME.
* WiFiServerSecure: Cache the SSL sessions
* Add SSL session caching to HTTPS server examples
* Document server SSL session caching
* Fix an incomplete sentence in the documentation
* Document BearSSL::Session
* Use the number of sessions instead of the buffer size in ServerSessions' constructors
* Add Wrong Password wifi status case
* Add wrong password case for status return
* Add wrong password case for debug
* Add Wrong password case to interactive example
* Add case for wrong password to station doc
* Add case for wrong password to resumeFromShutdown
* Add wrong password case to wifi readme
* Update ESP8266WiFiGeneric.cpp
This patch fixes some spelling typos in following files
bearssl-client-secure-class.rst
client-class.rst
scan-class.rst
scan-examples.rst
server-examples.rst
Added a bunch of missing "the"s and "a"s mostly. Didn't change any of the coding examples or the meaning of this example. Great example though, thanks.
* Deprecate SPIFFS, move examples to LittleFS
SPIFFS has been a great filesystem, but it has significant problems in
many cases (and it's also pretty slow). Development seems to have
slowed/stopped on the upstream version, and we're not able to provide
support or fix the known issues with it as-is.
Deprecate SPIFFS variable.
Update all examples to use LittleFS instead of SPIFFS.
Also, minor cleanup on very old examples which has obsolete delays
waiting for the Serial port to come up, or which were stuck at 9600 baud
because of their ancient AVR heritage.
Fixes#7095
* Remove leftover debug code
* Clean up comments in some examples
* Update documentation on SPIFFS deprecation
* Fix host tests to avoid deprecation warnings
* Fix cut-n-paste error
* Restore SpeedTest.ino, adjust to allow custom FSes
Co-authored-by: Develo <deveyes@gmail.com>
Fixes#5116Fixes#2743
The Arduino WiFiClient object allows sending the same packet to all
connected clients of a WiFiServer. In their implementation it may make
sense, but on the 8266 with things like SSL it doesn't.
Update the docs to note that WiFiServer::write() is a no-op, and that
the app should use the WiFiCliebnt::write() on all connected clients as
appropriate.
* Add a dump of received FP and CERT when in debug mode
To simplify BearSSL debugging, print the received FP (when it doesn't
match the expected) and the binary certificate (always), when in debug
mode.
* Add documentation section on FP mismatch in rare instances.
fix switching to static address with lwip2
For some reason, ip address is not propagated in a visible way for lwip2
when switching to static address (wifi.config()) *after* wifi.begin().
This patch calls lwip-v1.4's netif_set_addr() with the new ip address to set
all things up, just like it is done and right when wifi.begin() is called
after wifi.config().
Also tested when IPv6 is enabled.
fix documentation: It is more natural to set an IP address before starting WiFi
(.. and not after dhcp has started)
fixes#5839fixes#6024
* Upgrade to https: serving for JSON, links in docs
Fixes#5480
* Update boards.rst documentation
* Update more documentation http: refs to https:
* Remove obsolete staging info
* Drop obsolete versions from JSON programatically
After the final merge is done on the JSON, strip out any named versions
from the final product.
Removing 1.6.5-* and 2.5.0-beta(1,2,3) for now.
* Remove 2.4.0-rc(0/1) from JSON, too
Fixes#5996
* Add extensions to probe message for EC, others
probeMFLN was failing on some connection attempts to servers which only
supported EC based ciphers because it did not include the proper TLS
handshake extensions to list what kinds of ECs it supported.
Add those to the probeMFLN ClientHello message to make probes pass.
* Add client.getMFLNStatus method, returns MFLN state
After a connection it is useful to check whether MFLN negotiation
succeeded. getMFLNStatus returns a bool (valid only after
client.connect() succeeds, of course) indicating whether the requested
buffer sizes were negotiated successfully.
C arrays are 0 indexed, accordingly writing to array[255] actually writes to the 256th position, which is naturally out of bounds of a 255 item array. increasing the size of the array to 256 corrects that error. Also, 0 is an int and requires a cast into a char, '\0' is just a cleaner (a more syntactically pedantic) way to achieve the same end.
Fix link to WiFiEvents
Add note about WiFiClients and WiFiServers going down when a WiFi interface goes down, and that it's the user's responsibility to bring them back up.
BearSSLX509List, BearSSLSession, BearSSLPublicKey, and BearSSLPrivateKey
were all in the global namespace and not in the BearSSL:: one, due to an
oversight when they were originally created. Move them to the proper
namespace with the following mapping:
BearSSLX509List => BearSSL::X509List
BearSSLSession => BearSSL::Session
BearSSLPublicKey => BearSSL::PublicKey
BearSSLPrivateKey => BearSSL::PrivateKey
* fwupdate
* fw update to latest version:
WPA working, WEP+Open disabled by default. Need API change.
* helpers to follow sdk updates
* remove compare scripts - made a separate PR for them
* add wep api, restore original espressif comment (wep enabled does not prevent wpa)
* libmain was not up to date
* experimental: DTIM setting in WiFi.setSleepMode(WIFI_LIGHT/MODEM_SLEEP, DTIM-value)
with new getter: .getListenInterval() / .isSleepLevelMax()
* fixes
* fix debug message
* when not using listenInterval, set wifi sleep level to min
* update documentation
* update doc
