Commit Graph

13 Commits

Author SHA1 Message Date
Maarten van der Schrieck 3bca93b2d0 ports: Fix sys.stdout.buffer.write() return value.
MicroPython code may rely on the return value of sys.stdout.buffer.write()
to reflect the number of bytes actually written. While in most scenarios a
write() operation is successful, there are cases where it fails, leading to
data loss. This problem arises because, currently, write() merely returns
the number of bytes it was supposed to write, without indication of
failure.

One scenario where write() might fail, is where USB is used and the
receiving end doesn't read quickly enough to empty the receive buffer. In
that case, write() on the MicroPython side can timeout, resulting in the
loss of data without any indication, a behavior observed notably in
communication between a Pi Pico as a client and a Linux host using the ACM
driver.

A complex issue arises with mp_hal_stdout_tx_strn() when it involves
multiple outputs, such as USB, dupterm and hardware UART. The challenge is
in handling cases where writing to one output is successful, but another
fails, either fully or partially. This patch implements the following
solution:

mp_hal_stdout_tx_strn() attempts to write len bytes to all of the possible
destinations for that data, and returns the minimum successful write
length.

The implementation of this is complicated by several factors:
- multiple outputs may be enabled or disabled at compiled time
- multiple outputs may be enabled or disabled at runtime
- mp_os_dupterm_tx_strn() is one such output, optionally containing
  multiple additional outputs
- each of these outputs may or may not be able to report success
- each of these outputs may or may not be able to report partial writes

As a result, there's no single strategy that fits all ports, necessitating
unique logic for each instance of mp_hal_stdout_tx_strn().

Note that addressing sys.stdout.write() is more complex due to its data
modification process ("cooked" output), and it remains unchanged in this
patch. Developers who are concerned about accurate return values from
write operations should use sys.stdout.buffer.write().

This patch might disrupt some existing code, but it's also expected to
resolve issues, considering that the peculiar return value behavior of
sys.stdout.buffer.write() is not well-documented and likely not widely
known. Therefore, it's improbable that much existing code relies on the
previous behavior.

Signed-off-by: Maarten van der Schrieck <maarten@thingsconnected.nl>
2023-12-22 10:32:46 +11:00
Angus Gratton f5be0128e4 py: Add port-agnostic inline functions for event handling.
These are intended to replace MICROPY_EVENT_POLL_HOOK and
MICROPY_EVENT_POLL_HOOK_FAST, which are insufficient for tickless ports.

This implementation is along the lines suggested here:
https://github.com/micropython/micropython/issues/12925#issuecomment-1803038430

Currently any usage of these functions expands to use the existing hook
macros, but this can be switched over port by port.

This work was funded through GitHub Sponsors.

Signed-off-by: Angus Gratton <angus@redyak.com.au>
2023-12-08 12:47:00 +11:00
Damien George bfdf500ea5 py/mphal: Move configuration of ATOMIC_SECTION macros to mphal.h.
MICROPY_BEGIN_ATOMIC_SECTION/MICROPY_END_ATOMIC_SECTION belong more to the
MicroPython HAL rather than build configuration settings, so move their
default configuration to py/mphal.h, and require all users of these macros
to include py/mphal.h (here, py/objexcept.c and py/scheduler.c).

This helps ports separate configuration from their HAL implementations, and
can improve build times (because mpconfig.h is included everywhere, whereas
mphal.h is not).

Signed-off-by: Damien George <damien@micropython.org>
2023-12-01 14:14:08 +11:00
Damien George 8f20cdc353 all: Rename absolute time-based functions to include "epoch".
For time-based functions that work with absolute time there is the need for
an Epoch, to set the zero-point at which the absolute time starts counting.
Such functions include time.time() and filesystem stat return values.  And
different ports may use a different Epoch.

To make it clearer what functions use the Epoch (whatever it may be), and
make the ports more consistent with their use of the Epoch, this commit
renames all Epoch related functions to include the word "epoch" in their
name (and remove references to "2000").

Along with this rename, the following things have changed:

- mp_hal_time_ns() is now specified to return the number of nanoseconds
  since the Epoch, rather than since 1970 (but since this is an internal
  function it doesn't change anything for the user).

- littlefs timestamps on the esp8266 have been fixed (they were previously
  off by 30 years in nanoseconds).

Otherwise, there is no functional change made by this commit.

Signed-off-by: Damien George <damien@micropython.org>
2020-09-18 17:20:34 +10:00
Damien George ee50a6effe py/mphal.h: Introduce mp_hal_time_ns and implement on various ports.
This should return a 64-bit value being the number of nanoseconds since
1970/1/1.

Signed-off-by: Damien George <damien@micropython.org>
2020-08-22 16:13:44 +10:00
Damien George b7da67cdaa lib/utils/sys_stdio_mphal: Add support to poll sys.stdin and sys.stdout.
A port must provide the following function for this to work:

    uintptr_t mp_hal_stdio_poll(uintptr_t poll_flags);
2019-07-01 17:10:12 +10:00
Alexander Steffen 55f33240f3 all: Use the name MicroPython consistently in comments
There were several different spellings of MicroPython present in comments,
when there should be only one.
2017-07-31 18:35:40 +10:00
Alexander Steffen 299bc62586 all: Unify header guard usage.
The code conventions suggest using header guards, but do not define how
those should look like and instead point to existing files. However, not
all existing files follow the same scheme, sometimes omitting header guards
altogether, sometimes using non-standard names, making it easy to
accidentally pick a "wrong" example.

This commit ensures that all header files of the MicroPython project (that
were not simply copied from somewhere else) follow the same pattern, that
was already present in the majority of files, especially in the py folder.

The rules are as follows.

Naming convention:
* start with the words MICROPY_INCLUDED
* contain the full path to the file
* replace special characters with _

In addition, there are no empty lines before #ifndef, between #ifndef and
one empty line before #endif. #endif is followed by a comment containing
the name of the guard macro.

py/grammar.h cannot use header guards by design, since it has to be
included multiple times in a single C file. Several other files also do not
need header guards as they are only used internally and guaranteed to be
included only once:
* MICROPY_MPHALPORT_H
* mpconfigboard.h
* mpconfigport.h
* mpthreadport.h
* pin_defs_*.h
* qstrdefs*.h
2017-07-18 11:57:39 +10:00
Paul Sokolovsky a97284423e extmod/utime_mphal: Factor out implementations in terms of mp_hal_* for reuse.
As long as a port implement mp_hal_sleep_ms(), mp_hal_ticks_ms(), etc.
functions, it can just use standard implementations of utime.sleel_ms(),
utime.ticks_ms(), etc. Python-level functions.
2016-10-14 20:14:01 +03:00
Paul Sokolovsky 41167554e4 py/mphal.h: If virtpin API is used, automagically include its header. 2016-06-19 00:12:37 +03:00
Paul Sokolovsky 751e3b7a82 extmod/virtpin: Initial implementation of open-ended C-level Pin interface.
Using usual method of virtual method tables. Single virtual method,
ioctl, is defined currently for all operations. This universal and
extensible vtable-based method is also defined as a default MPHAL
GPIO implementation, but a specific port may override it with its
own implementation (e.g. close-ended, but very efficient, e.g. avoiding
virtual method dispatch).
2016-05-27 01:08:43 +03:00
Paul Sokolovsky 5a2a4e9452 py/mphal.h: Provide default prototypes for mp_hal_delay_us/mp_hal_ticks_us.
Similar to existing mp_hal_delay_ms/mp_hal_ticks_ms.
2016-05-21 02:13:50 +03:00
Damien George 731f359292 all: Add py/mphal.h and use it in all ports.
py/mphal.h contains declarations for generic mp_hal_XXX functions, such
as stdio and delay/ticks, which ports should provide definitions for.  A
port will also provide mphalport.h with further HAL declarations.
2015-10-31 19:14:30 +03:00