The latest versions of Arduino IDE shifted the responsibility for precompiled libraries support to the core developers, which breaks precompiled library support in esp32 Arduino core. See https://github.com/arduino/ArduinoCore-avr/pull/52 for more details:
```
In this new version of the builder we are not doing any heuristics to find the right spot where the ldflags should be inserted (this was causing many bugs on its own); instead, we fully trust the core makers to add explicit support to precompiled libs.
```
This chage re-enables precompiled library support in the esp32 Arduino core.
SPIFFS causes crashes if you attempt to rmdir. Since there are no true directories in spiffs, this ought to be a noop. It looks like @me-no-dev worked around this by using unlink instead of rmdir, which works in fatfs and doesn't panic spiffs. This behavior is not universal. In order to get littlefs working, it would be good to get this back to conformity. Rather than digging deep into the upstream spiffs, I just check the mountpoint and noop if it is "/spiffs". So, if the user has changed the mountpoint, this will not work, but I think it's a pretty good tradeoff.
Successful exploitation could lead to arbitrary code execution.
The bug can be reproduced by running the following in a browser:
```
const formData = new FormData();
for (let i = 0;i < 33;++i) { formData.append("foo", i.toString()); }
await fetch("http://esp.local", { method: 'POST', body: formData });
```
Informed by the discussion in the bug and the code in 'that other branch'
the fix was clear. Just set a flag if we start handling a write, and
use that flag to guard the long write complete call.
Background
The current implementation of Update() uses the spi_flash_* api to write and read from flash. These functions ignore the partition->encrypted flag and always write raw data to flash even if the partition is marked as encrypted.
Changes in this PR
Update() now uses the esp_partition_* api.
Wrapper functions for esp_partition_* added to ESP.cpp. This was done to maintain a consistent approach to the way the spi_flash_* functions were used. I note though that not all of the esp-idf functions are used are wrapped, for example esp_ota_get_next_update_partition() so it may be that these should not be added?
The current implementation of Update() changes the first (magic) byte of firmware to 0xFF on write, and then when the firmware is completely written changes it back to ESP_IMAGE_HEADER_MAGIC. This works without erasing the sector because flash bits can be changed from 1->0 (but not 0->1). If the flash is encrypted then the actual data written to flash will not be all ones, so this approach will not work. In addition, encrypted flash must be written in 16 byte blocks. So, instead of changing the first byte the changed code stashes the first 16 bytes, and starts writing at the 17th byte, leaving the first 16 bytes as 0xFF. Then, in _enablePartition() the stashed bytes can be successfully written.
Benefits
Whilst it's not possible to use encrypted flash directly from either the Arduino IDE or PIO it's reasonably straightforward to compile and flash a bootloader with the necessary support from a simple esp-idf project and then use ArduinoOTA for subsequent updates. This PR enables the use of this workflow until such time as encrypted flash is supported, and is a first (small) step toward adding support.
Regardless of the above, the esp_partition_* api is recommended over the api_flash_* api.
Application code should mostly use these esp_partition_* API functions instead of lower level spi_flash_* API functions. Partition table API functions do bounds checking and calculate correct offsets in flash, based on data stored in a partition table.
By default the disconnect is broadcasted to every clients. So if you call disconnect on one connected client, they'll all be disconnected if we don't filter the event by conn_id.
* ESP.getChipModel() returns model of the chip
* ESP.getChipCores() returns the core count.
* Example gives chip model, revision and core count.
* Read efuse for chipmodel
Co-authored-by: Martijn Scheepers <ms@SDNengineering.nl>
* Fix issue #3833, data parsing of Eddystone TLM data frame
Add Beacon scanner example to show usage of BLEEddystoneTLM class and BLEEddystoneURL class
Add EddystoneTLM beacon example
Add EddystoneURL beacon example
* Fix buffer size for .toString()
When connecting using transportTraits, the CA and client certificates are ignored after the initial _client->connect() is called. This is because on connect, WiFiClientSecure will call start_ssl_client with _CA_Cert and other cert options set to null unless setCACert, setCertificate etc. are called before connect. Running _transportTraits->verify after connect therefore does exactly nothing. It's easy to verify that this is the case by passing a CACert to HTTPClient with verbose logging enabled - the logs will say "WARNING: Use certificates for a more secure communication!" which is only present when both PSK and CA are null. This change fixes the issue.
Real DNS resolving timeout used by lwip library is 14[s] (7[s] for DNS1 + 7[s] for DNS2). Function WiFiGenericClass::hostByName() has timeout set to lower value (only 4[s]), so callback function may be called after this low timeout and it may overlappe stack memory used now by other function.
Fixes#3722
They are all broadly similar, all being based on the ESP32-D0WD core, but have
some subtle differences between variants around PSRAM inclusion and camera pin
mappings.
The ESP32CAM "unit" product (SKU: U007) has no PSRAM and maps the
"Pixel Data 0" (Y2 GPIO/OV2640 D2) camera pin to IO17 rather than IO32 as is
the case with most other M5Stack ESP32 camera devices.
The ESP32CAM also requires the "hmirror" and "vflip" camera configuration
bits setting in order to capture a true image.
The relevant M5Stack pin configuration documentation can be found here:
https://docs.m5stack.com/#/en/unit/esp32cam?id=pinmap
