Basically, in the portability layer, it is checked if the socket is
NON-block, and if not, then even the EAGAIN and EWOULDBLOCK errors are
diverted to a RECV error. This causes a problem for sockets with
receive timeouts set. When such a timeout is set, the condition for
NON_BLOCK isn't met and hence a hard error is returned.
Searching for EAGAIN and EWOULDBLOCK in lwip returns only 3 results
(accept, recvfrom, close) and all of them look to be genuine cases for
EWOULDBLOCK. So removing this check to make receive timeout with TLS
work.
- In some cases where the HTTP URL contains the port number
(http://hostname:334), the DNS querier fails to resolve the hostname.
- Hence we have to populate the port number ourselves.
- This can only be done based on whether we get an IPv4 or IPv6
address.
Purpose:
1. TLS calls can be too many, and require a user to know the expected behaviour. A simple TLS socket wrapper that can be used in any higher level protocol.
2. Uses OpenSSL compatibility layer, so applications using esp-tls can be built on the host, and it should just work on ESP
The expected usage is:
esp_pthread_set_cfg(cfg);
pthread_create()
If the inherit flag is set, then all subsequent threads forked by this
thread will also inherit this configuration. This avoids having to
change/prefix this for each and every pthread_create() call.
Intention is to partition the demo into multiple files, so that the
main program is quite easy to follow.
1. connectlib.c: For any URL parsing and TCP connection related stuff
2. sh2lib.c: Convenience functions for HTTP2+TLS. The goal here is to
expose a simpler API than nghttp2. If most usecases end up being
served with this library, it could potentially be moved into a separate
component
The mutex is common across all the threads. It needn't be held across
the init_routine() call as long as the 'once' behaviour is guaranteed
Saw a deadlock case, where init_routine of one thread was waiting for
the completion of init_routine in another thread.
t2: wait for command
t1: pthread_once:
lock once_mux
init_routine:
inform thread t2
wait for signal from t2
t2: received command
pthread_once
lock once_mux (already held by t1)
---- Deadlock ----
1. Hello World application shows no footprint difference before and
after this change
2. examples/ethernet/ethernet application compiles properly (can't
test with my board)
This is no longer required since the functions automatically get
pulled in based on the usage. A quick summary of footprint
comparisions before and after these set of patches is shown below:
Hello-World: (simplified for readability)
old Total image size:~ 104902 bytes (.bin may be padded larger)
old Total image size:~ 105254 bytes (.bin may be padded larger)
Per-archive contributions to ELF file:
Archive File DRAM .data & .bss IRAM Flash code & rodata Total
old libesp32.a 1973 177 4445 3939 2267 12801
new libesp32.a 1973 185 4473 3939 2267 12837
new libnvs_flash.a 0 92 0 274 8 374
new libstdc++.a 0 0 0 24 0 24
For some reason, nvs_flash.a (~400bytes) gets pulled in (particularly
the nvs_flash_init() function).
Power-Save: (simplified for readability)
old Total image size:~ 421347 bytes (.bin may be padded larger)
old Total image size:~ 421235 bytes (.bin may be padded larger)
old libtcpip_adapter.a 0 81 0 1947 115 2143
new libtcpip_adapter.a 0 69 0 1897 115 2081
The size actually shrinks a bit, since the AP interface function
doesn't get pulled in.
Since only the used interface's start function gets called, it pulls
in only the functions that are required in the current application,
thereby saving footprint.
Restart being a lower-layer system-level function, needn't depend on
the higher level Wi-Fi libraries.
This also enables us to get rid of one more WIFI_ENABLED ifdef check