Using __errno() function, and redirect it to use mp_stream_errno from
stream module. This is pre-requisite for integrating with 3rd-party libs,
like BerkeleyDB.
To filter out even prototypes of mp_stream_posix_*() functions, which
require POSIX types like ssize_t & off_t, which may be not available in
some ports.
The configuration bits for the UART register were wrong and the parity
couldn't be enabled, because the exist_parity member hasn't been updated. I
took this ESP8266 register description (http://esp8266.ru/esp8266-uart-reg/)
as reference.
Verification has been done with a logic analyzer.
The idea behind decrease is: bytecode and other static data is also kept on
heap, and can easily become half of heap, then setting threshold to half of
heap will have null effect - GC will happen on complete heap exhaustion like
before. But exactly in such config maintaining heap defragmented is very
important, so lower threshold to accommodate that.
To start with, the critical scripts _boot.py and flashbdev.py are frozen
to improve performance and reduce RAM consumption.
Saves about 1000 bytes of heap RAM for a bare boot with filesystem.
The time stamp is taken from the RTC for all newly generated
or changed files. RTC must be maintained separately.
The dummy time stamp of Jan 1, 2000 is set in vfs.stat() for the
root directory, avoiding invalid time values.
Based on my experience, there's rather non-zero chance to have an image be
flashed incorrectly. As --verify option is now works well in teh latest
esptool.py, enable it by default.
By design, at wake up from deepsleep, the RTC timer will be reset, but
the data stored in RTC memory will not [1]. Therefore, we have to adjust
delta in RTC memory before going into deepsleep to get almost correct
time after waking up.
[1] http://bbs.espressif.com/viewtopic.php?t=1184#p4082
Instead of calling strlen(), which won't work if there're 32 chars in
returned ESSID. struct bss_info::ssid_len is not documented in SDK API
Guide, but is present in SDK headers since 1.4.0. Just in case, previous
code is left commented.
ESP-SDK system_get_rtc_time() returns uint32 and therefore overflow
about every 7:45h. Let's write the last state of system_get_rtc_time()
in RTC mem and use it to check for overflow. This commit require running
pyb_rtc_get_us_since_2000() at least once within 7 hours to avoid
overflow.
This implementation makes use of vfs.stat() and therefore has the same
properties. Known issues for all ports: uos.stat(".") on the top level
returns the error code 22, EINVAL. The same happens with
uos.stat("dirname/") where dirname IS the name of a directory.
Ctrl-C will raise a KeyboardInterrupt and stop the scan (although it will
continue to run in the background, it won't report anything). If
interrupted, and another scan() is started before the old one completes
in the background, then the second scan will fail with an OSError.
