engine.core.log source code

1 /*
2     Copyright © 2020, Luna Nielsen
3     Distributed under the 2-Clause BSD License, see LICENSE file.
4     
5     Authors: Luna Nielsen
6 */
7 module engine.core.log;
8 import std.stdio;
9 import std.file;
10 import std.format;
11 import core.stdc.stdlib : exit;
12 
13 __gshared Logger AppLog;
14 
15 /**
16     A logger
17 */
18 class Logger {
19 private:
20     bool logFileOpened = false;
21     File logFile;
22     string logFileName;
23 
24     void writeLogToFile(string text) {
25         
26         // Open log file if need be
27         if (!logFileOpened) this.openLogFile();
28 
29         // Write to log
30         logFile.writeln(text);
31         logFile.flush();
32     }
33 
34     void openLogFile() {
35         this.logFile = File(this.logFileName, "a");
36     }
37 
38 public:
39     /**
40         Whether to write logs to file
41 
42         TODO: implement
43     */
44     bool logToFile;
45 
46     /**
47         Creates a new logger
48     */
49     this(bool logToFile = false, string logFile = "applog.log") {
50         this.logToFile = logToFile;
51         this.logFileName = logFile;
52 
53         if (logToFile) {
54             this.openLogFile();
55         }
56     }
57 
58     /**
59         Closes the logger and its attachment to the log file
60     */
61     ~this() {
62         if (logFileOpened) logFile.close();
63     }
64 
65     /**
66         Write info log to stdout
67     */
68     void info(T...)(string sender, string text, T fmt) {
69         string logText = "[%s] info: %s".format(sender, text.format(fmt));
70         writeln(logText);
71         
72         if (logToFile) {
73             this.writeLogToFile(logText);
74         }
75     }
76 
77     /**
78         Write warning log to stdout
79     */
80     void warn(T...)(string sender, string text, T fmt) {
81         string logText = "[%s] warning: %s".format(sender, text.format(fmt));
82         writeln(logText);
83         
84         if (logToFile) {
85             this.writeLogToFile(logText);
86         }
87     }
88 
89     /**
90         Writes error to stderr
91     */
92     void error(T...)(string sender, string text, T fmt) {
93         string logText = "[%s] error: %s".format(sender, text.format(fmt));
94         stderr.writeln(logText);
95 
96         if (logToFile) {
97             this.writeLogToFile(logText);
98         }
99     }
100 
101     /**
102         Writes a fatal error to stderr and quits the application with status -1
103     */
104     void fatal(T...)(string sender, string text, T fmt) {
105         string logText = "[%s] fatal: %s".format(sender, text.format(fmt));
106         stderr.writeln(logText);
107 
108         if (logToFile) {
109             this.writeLogToFile(logText);
110         }
111 
112         exit(-1);
113     }
114 }