From v5.1 to v5.2

Deprecated: ESP32 IDF version 4.3, 4.4 and 5.0

The older 4.3, 4.4 and 5.0 versions of the ESP32 IDF are deprecated and support for them will be removed in the future. The installation scripts now install IDF version 5.2 by default. See IDF versions for further details.

Windows installer

The Windows installer makes use of custom chocolatey packages, which are out of date. These packages are separate from the main Sming repository which makes maintenance problematic.

The procedure has therefore been revised to use installation scripts instead of these chocolatey packages. This brings the installation procedure closer to that for Linux/MacOS.

The initial installation step to bootstrap the installation remains unchanged: The choco-install.cmd script is fetched from the Sming develop branch and executed. The custom choco scripts have been replaced with scripted logic.

Installation of toolchains is done as a separate step as it does not require administrative privileges.

The documentation at https://sming.readthedocs.io/en/latest/getting-started/windows/index.html has been updated to reflect these changes.

PartitionStream: Breaking change

The Storage::PartitionStream constructors with blockErase parameter have been deprecated. The intended default behaviour is read-only, however previously this also allowed writing without block erase. This can result in corrupted flash contents where the flash has not been explicitly erased beforehand.

The new constructors instead use a Storage::Mode so behaviour is more explicit. The default is read-only and writes will now be failed. For example:

Storage::PartitionStream stream(myPartition, Storage::Mode::BlockErase);

64-bit time_t

There is some variability in whether time_t is 32 or 64 bits. See Issue #2758.

This is dependent on the toolchain and accompanying C library.

32-bits:

  • Esp32 IDF 4.x

  • Windows Host (using mingw)

  • Linux host builds prior to Sming v5.2

Building for these will generate a warning **Y2038** time_t is only 32-bits in this build configuration. If you cannot upgrade then build with STRICT set to 1.

Range of time_t:

value

Timestamp

-0x80000000

1901-12-13 20:45:52

0x00000000

1970-01-01 00:00:00

0x7fffffff

2038-01-19 03:14:07

All others use 64-bit values.

For reference, C library source code can be found here https://sourceware.org/git/?p=newlib-cygwin.git;a=blob;f=newlib/libc/

Rp2040 builds with standard ARM toolkit so probably accommodated by the standard repo.

Espressif toolchains use forks:

Toolchain versions updated

Esp8266

The installer has been updated to use the latest toolchain (Feb 23), gcc 10.3.

Esp32 IDF

The installation scripts now install IDF version 5.2 by default. See IDF versions for further details.

RP2040

The installer has been updated to use the latest toolchain (Oct 23), gcc 13.2.

Bearssl client certificate validation

Using ENABLE_SSL=Bearssl in a client application, no verification on the server certificate is performed. This is a potential security issue.

Attempting the same thing with Axtls results in an X509_VFY_ERROR_NO_TRUSTED_CERT error. Applications must explicitly call HttpRequest::onSslInit() and set the verifyLater flag. This extra step ensures that security checks are not unintentionally bypassed.

The same behaviour is now presented when using Bearssl, and will now fail with X509_NOT_TRUSTED.

FlashString copy support removed

The FlashString previously supported copies (references) like this:

FlashString emptyString;
FlashString stringCopy(FS("Inline string"));

DEFINE_FSTR_DATA_LOCAL(flashHelloData, "Hello");
auto myCopy = flashHelloData;

These will now fail to compile. Copy construction and assignment has been explicitly deleted so avoid unintentional side-effects.

Objects should always be passed by reference.

spi_flash functions

Several definitions have been deprecated/removed as they serve no purpose since partitions introduced.

flashmem_get_first_free_block_address()

flashmem_get_info() returns a common SPIFlashInfo structure for all architectures. Esp8266 previously had a structure definition with two unknown fields as this directly represented the contents of the first 16 bytes of flash. These have been removed and the structure unpacked.

The following macro definitions have been removed for esp8266:

  • SYS_PARAM_SEC_COUNT

  • FLASH_WORK_SEC_COUNT

  • INTERNAL_FLASH_SIZE

These are related to the fixed system parameter block at the end of flash memory. With partitions this is relocatable so any code which depends on these will be wrong.

CsvReader library

The CsvReader class has been moved out of Core/Data and into CSV Reader Library which has additional capabilities. Changes to existing code:

  • Add CsvReader to your project’s COMPONENT_DEPENDS

  • Change #include <Data/CsvReader> to #include <CSV/Reader.h>

  • Change CsvReader class to CSV::Reader