Detailed Description

Diagnostic logging to UART and/or Ethernet ports.

Log objects are used for diagnostic logging, with a few simple formatting options. They are intended for simple debugging while being much lighter-weight than printf() or sprintf(). Log messages can be conveyed to a console, a UART, or even a network interface. Each Log message carries a priority code to allow filtering.

The objects in this file are used to generate log messages. For receiving messages,

See also: log_cbor.h or the "test/log_viewer" tool.

Each Log object formats and emits a single human-readable message. The Log object is ephemeral, with chaining for readable syntax. Additional "write" calls append information to the message; the final message is sent when the Log object falls out of scope.

Each of the three examples below produces the same formatted message:

using satcat5::log::Log;
 
void example1(u8 errcode) {
    Log(satcat5::log::WARNING, "Oh noooo").write(errcode);
}
 
void example2(u8 errcode) {
    Log(satcat5::log::WARNING).write("Oh noooo").write(errcode);
}
 
void example3(u8 errcode) {
    Log log(satcat5::log::WARNING);
    log.write("Oh noooo");
    log.write(errcode);
}

When the Log object falls out of scope, the message contents are written to every object that defines the log::EventHandler interface.

Definition in file log.h.

#include <satcat5/list.h>
#include <satcat5/types.h>

Include dependency graph for log.h:

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Go to the source code of this file.

Classes
class	satcat5::log::EventHandler
	Defines the interface for accepting Log messages. More...

class	satcat5::log::ToWriteable
	Copy `Log` messages to any `Writeable` interface. More...

class	satcat5::log::LogBuffer
	Internal buffer used by the `Log` class. More...

class	satcat5::log::Log
	The `Log` class creates and formats one log message. More...

Macros
#define	SATCAT5_LOG_MAXLEN 255

#define	SATCAT5_LOG_CONCISE 1

#define	SATCAT5_WELCOME_EMOJI "\xf0\x9f\x9b\xb0\xef\xb8\x8f\xf0\x9f\x90\xb1\xf0\x9f\x95\x94"

Functions
const char *	satcat5::log::priority_label (s8 priority)
	Convert priority code to a human-readable UTF-8 string. More...

bool	satcat5::log::pre_test_reset ()
	Hard-reset of global variables at the start of each unit test. More...

Variables
constexpr s8	LOG_DEBUG = satcat5::log::DEBUG

constexpr s8	LOG_INFO = satcat5::log::INFO

constexpr s8	LOG_WARNING = satcat5::log::WARNING

constexpr s8	LOG_ERROR = satcat5::log::ERROR

constexpr s8	LOG_CRITICAL = satcat5::log::CRITICAL


constexpr s8	satcat5::log::DEBUG = -20
	Define basic priority codes for log messages. More...

constexpr s8	satcat5::log::INFO = -10
	Define basic priority codes for log messages. More...

constexpr s8	satcat5::log::WARNING = 0
	Define basic priority codes for log messages. More...

constexpr s8	satcat5::log::ERROR = +10
	Define basic priority codes for log messages. More...

constexpr s8	satcat5::log::CRITICAL = +20
	Define basic priority codes for log messages. More...

Function Documentation

◆ pre_test_reset()

bool satcat5::log::pre_test_reset ( )

Hard-reset of global variables at the start of each unit test.

(Unit test only, not recommended for use in production software.) This may leak memory but prevents cross-test contamination. Returns true if globals were already in the expected state.

Definition at line 26 of file log.cc.

◆ priority_label()

const char * satcat5::log::priority_label ( s8 priority )

Convert priority code to a human-readable UTF-8 string.

By default, the priority code is a UTF-8 emoji. For example, WARNING gets the "caution" sign and CRITICAL gets a skull and crossbones. To replace this with a fixed-width plaintext code, set SATCAT5_LOG_EMOJI = 0.

Definition at line 116 of file log.cc.

Variable Documentation