elpekenin/logging.h

Custom logging utilities, inspired by Python’s logging module.

Note

Under the hood, this is just a wrapper on top of printf().

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enum feature_t

Different features that may emit log messages.

Warning

If you want to add a new one, it has to be the last element.

enumerator UNKNOWN

enumerator LOGGER

enumerator QP

enumerator SCROLL

enumerator SIPO

enumerator SPLIT

enumerator SPI

enumerator TOUCH

enumerator MAP

enumerator ALLOC

enum log_level_t

Different level of severity. Used to filter out messsages.

Warning

If you want to add a new one, it has to be the last element.

enumerator LOG_NONE

enumerator LOG_DEBUG

enumerator LOG_INFO

enumerator LOG_WARN

enumerator LOG_ERROR

Hint

The logging() function will apply an extra transformation to your input, based on a custom format. Its specifiers being:

• %F: The feature’s name (nothing if UNKNOWN).

• %LL: The message’s level (long). Eg: DEBUG.

  • These strings are set in level_str.

• %LS: Print only the first char of the previous string. Eg: D.

• %M: The actual message created by msg and ... passed to logging(). With its regular format.

• %T: Current time, you can override log_time() to hook it with a RTC or whatever.

  • Default implementation is seconds since boot.

• %%: Write a literal %.

For example, with format of [%F] (%LL) -- %M | %T, messages would look like: [QP] (DEBUG) -- <msg%args> | 3s

You can query the current format using get_logging_fmt() or change it with set_logging_fmt().

int logging(feature_t feature, log_level_t level, const char *msg, ...)

Emit a logging message.

Parameters:

• feature – Piece of code being logged.

• level – Severity of the message.

• msg – Format string for the message.

• ... – Variadic arguments to fill the specifiers in msg.

Returns:

Whether message could be emited.

See also

elpekenin/errno.h

uint8_t get_logging_fmt_len(void)

Get length of the current logging format.

You may use this to allocate a big-enough buffer before calling get_logging_fmt().

void get_logging_fmt(char *dest)

Copy the current logging format into dest.

Tip

Destination must be big enough, use get_logging_fmt_len().

int set_logging_fmt(const char *fmt)

Change the logging format.

Parameters:

• fmt – The new format, can’t be longer than MAX_LOG_FMT_LEN.

Returns:

Whether it could be set

See also

elpekenin/errno.h

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log_level_t get_level_for(feature_t feature)

Get the current level for a feature. Messages with a lower severity are dropped.

void set_level_for(feature_t feature, log_level_t level)

Change the level set to for a feature.

void step_level_for(feature_t feature, bool increase)

Increase (or decrease) by one the level set for a feature.

The direction is based on increase.

Attention

From this point, the functions are mostly implementation details.

You, most likely, don’t need to know anything about them.

log_level_t get_message_level(void)

Get the severity of the message being emited.

This may be used by a sendchar_func_t internally.

const char *log_time(void)

Get a string representing the current time.

By default, seconds since boot, but it can be overwriten.

MAX_LOG_FMT_LEN

Maximum length of the logging format’s string.

Default: 255.

ASSERT_FEATURES(__array)

Check that an array has as many elements as features are defined.

If not, compilation will error out.

ASSERT_LEVELS(__array)

Check that an array has as many elements as logging levels are defined.

If not, compilation will error out.

void dump_stack(void)

Utility to print previous execution’s crash traceback.

void print_str(const char *str, const sendchar_func_t func)

Print a string using the given function.

Caution

Logging’s own formatting is not applied.

Parameters:

• str – Regular string (no format specifiers).

• func – The function used to process the string.

void print_u8(const uint8_t val, const sendchar_func_t func)

Print a number using the given function.

Caution

Logging’s own formatting is not applied.

Parameters:

• val – Number to be printed.

• func – The function used to process the string.

void print_u8_array(const uint8_t *list, const size_t len, const sendchar_func_t func)

Print a list of numbers using the given function.

Caution

Logging’s own formatting is not applied.

Parameters:

• list – Start of the array.

• len – How long list is.

• func – The function used to process the string.

log_success(success, feature, msg, args...)

Run feature, msg and args... through logging().

Severity will be LOG_DEBUG if success is true, else LOG_ERROR.