EasyLogger

EasyLogger

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1. Introduction

EasyLogger is an ultra-lightweight (ROM<1.6K, RAM<0.3K), high-performance C/C++ log library, which is ideal for resource-sensitive software projects, such as: IoT products, wearable devices, smart homes, and more. Compared with well-known C/C++ log libraries such as log4c and zlog, EasyLogger has simpler functions and provides fewer interfaces to users, but it will be quick to get started. More practical functions support dynamic expansion in the form of plug-ins.

1.1 Main Features

• Supports user-defined output methods (for example: terminal, file, database, serial port, 485, Flash...);
• The log content can include levels, timestamps, thread information, process information, etc.;
• Log output is designed as a thread-safe method and supports asynchronous output and buffered output modes;
• Supports multiple operating systems (RT-Thread, UCOS, Linux, Windows, Nuttx...), and also supports bare metal platforms;
• Logs support RAW format and support hexdump ;
• Support dynamic filtering by tags , levels , and keywords ;
• Logs at all levels support different colors to display;
• Strongly extensible, supports the expansion of new functions in the form of plug-ins.

Explanation of nouns:

• 1. RAW format: unformatted original log.
• 2. Tags: In the software, you can set tags for logs that need to be printed according to files, modules, functions, etc. to realize log classification.

1.2 Plug-in

• 1. Flash: Use the Flash operation interface provided by the EasyFlash library, and directly store logs in Flash without the need for a file system.
• 2. File: Supports file transfer, file loop saving and other functions related to file log output.
• 3. Stay tuned...

1.3 Star & Fork

I will provide more plugins later. We are also very welcome to design and develop more practical plug-ins and functions to improve EasyLogger (Github|OSChina|Coding) . If you think this open source project is great, you can click Star in the upper right corner of the project homepage and recommend it to more friends in need.

2. Use

2.1 Parameter configuration

EasyLogger has properties such as filtering method, output format, and output switch.

• The filtering method supports filtering according to labels, levels, and keywords;
• The log output can be turned on/off dynamically;
• Dynamic and static output levels can be set
  • Static: First-level switch, defined by macros, used in the compilation stage;
  • Dynamic: The secondary switch is used during the operation stage through the API interface.

Note: Currently, parameter configuration and output methods are singleton mode, that is, only one configuration method is supported globally. In this mode, the software will be simpler, but it cannot support complex output methods.

2.2 Output level

Refer to Android Logcat, the highest level is 0 (Assert) and the lowest level is 5 (Verbose).

 0.[A]：断言(Assert)
1.[E]：错误(Error)
2.[W]：警告(Warn)
3.[I]：信息(Info)
4.[D]：调试(Debug)
5.[V]：详细(Verbose)

2.2.1 Output colorful logs

The default color effect of logs at each level is as follows. Users can also set the colors and font styles of logs at elog_cfg.h according to their preferences.

2.3 Output filtering

Support filtering by level, label and keyword . When there is a lot of log content, the filtering function can be used to locate the log faster to ensure the readability of the log. For more filter function settings and details, please read the docszhapikernel.md document

Note: RAW format and hexdump format logs do not support tags and keyword filtering.

2.4 Output format

The output format supports: level, time, label, process information, thread information, file path, line number, method name. Each priority level can set the output format independently.

2.5 Output method

Through user porting, any output method can be supported. However, for new functions that may be introduced in a certain output method, it needs to be implemented through plug-ins, such as file transfer, retrieval of Flash logs, etc. More plug-ins will be open source later. The following is a brief comparison of some of the output usage scenarios:

• Terminal: convenient for users to view dynamically and does not have storage functions;
• Files and Flash: Both have storage functions, and users can view historical logs. However, the file method requires the support of the file system, and the Flash method is more suitable for small embedded devices without file systems.

2.6 Demo

2.6.1 Core functions

The following figure shows the input commands in the terminal to control the log output and filter settings, which more intuitively demonstrates the core functions of EasyLogger.

• Demo path: demoosrt-threadstm32f10x
• API documentation: docszhapikernel.md
• Migration documentation: docszhportkernel.md

2.6.2 Flash Log (save the log to Flash)

The following process is to output logs through the console and store the output logs into Flash. Restart and read the last saved log, and finally clear the Flash log.

• Demo path: demoosrt-threadstm32f10x
• API documentation: docszhapiflash.md
• Migration documentation: docszhportflash.md

2.6.2 File Log (save the log to a file)

The FIle plug-in allows you to automatically save logs to files. Each file can be sized. After exceeding the specified size, a new file will be automatically created to store the log.

3. Documentation

For specific content, refer to the file under docszh . Be sure to use it after reading the document .

4. Later

• Flash storage: Add log storage and reading functions to EasyFlash, allowing EasyLogger to seamlessly connect with it. Make logs easier to store in non-file systems and have the function of historical log retrieval;
• Configuration file: Configuration file under the file system;
• File transfer: File transfer is supported by capacity and time in the file system;
• Log Assistant: Develop a cross-platform log assistant, compatible with Linux, Windows, and Mac systems. Open the Assistant to view, filter (support regular expressions), sort, save logs, etc. Front-end: HTML5 + Bootstrap + AngularJS + NW.js, back-end: Rust + iron + rust-websocket + serial-rs;
• Asynchronous output: Currently, the log output and user code are synchronized. Although this method is simple, there is no problem of log overwriting. However, on platforms with low output speeds, the software operation speed will be reduced due to the addition of logging functions. Therefore, asynchronous output will be added later, and keyword filtering can also be placed in asynchronous output;
• Arduino: Added Arduino lib and provided its demo;

5. Permit

MIT Copyright (c) [email protected]