Since these functions receive the pointer to reent structure, they
should set errno in it rather than using thread-local errno.
This didn't cause practical issues because console functions in IDF
are only called from threads, and in that case 'r' is a pointer to
the thread-local structure, so &errno is the same thing as
&__errno_r(r). Still, fixing this for consistency.
When CONFIG_VFS_SUPPORT_IO is disabled, _read_r and _write_r
implementations in syscalls.c are used to provide console I/O via
esp_rom_uart_tx_one_char/esp_rom_uart_rx_one_char.
When newlib opens a (FILE*) stream, it calls fstat to check if the
underlying file is character-oriented. In this case, it configures the
stream to use line buffering. Otherwise (or if fstat fails) the stream
is opened as block buffered.
Since fstat wasn't provided, stdin/stdout/stderr streams got opened in
block buffered mode. For console, we need line buffered output so that
the stream buffer is flushed each time a complete line (ending with
'\n') is sent to stdout or stderr.
Fix by implementing _fstat_r stub, setting st->st_mdoe=S_IFCHR.
* Target components pull in xtensa component directly
* Use CPU HAL where applicable
* Remove unnecessary xtensa headers
* Compilation changes necessary to support non-xtensa gcc types (ie int32_t/uint32_t is no
longer signed/unsigned int).
Changes come from internal branch commit a6723fc
- spaces->tabs in tasks.c
- update vfs_uart.c to use per-UART locks
- add license to vfs_uart.c
- allocate separate streams for stdout, stdin, stderr, so that they can be independently reassigned
- fix build system test failure
