awl/logawl/logger.go
2022-06-26 14:01:13 -04:00

101 lines
2.5 KiB
Go

package logawl
import (
"fmt"
"os"
"sync/atomic"
"time"
)
// Calling New instantiates Logger
//
// Level can be changed to one of the other log levels (FatalLevel, ErrorLevel, InfoLevel, DebugLevel)
func New() *Logger {
return &Logger{
Out: os.Stderr,
//TODO: Make cli.go change this value when calling logawl.New()
Level: InfoLevel, //Default value is InfoLevel
}
}
// Takes any and prints it out to Logger -> Out (io.Writer (default is std.Err))
func (l *Logger) Println(v ...any) {
if atomic.LoadInt32(&l.isDiscard) != 0 {
return
}
switch l.Level { //Goes through log levels and does stuff based on them (Fatal os.Exit...etc)
case 0:
l.Printer(0, fmt.Sprintln(v...)) //Fatal level
os.Exit(1)
case 1:
l.Printer(1, fmt.Sprintln(v...)) //Error level
case 2:
l.Printer(2, fmt.Sprintln(v...)) //Info level
case 3:
l.Printer(3, fmt.Sprintln(v...)) //Debug level
}
}
// Formats the log header as such <LogLevel> YYYY/MM/DD HH:MM:SS (local time) <the message to log>
func (l *Logger) formatHeader(buf *[]byte, t time.Time, line int) {
if lvl, err := l.UnMarshalLevel(); err == nil {
*buf = append(*buf, lvl...)
year, month, day := t.Date()
formatter(buf, year, 4)
*buf = append(*buf, '/')
formatter(buf, int(month), 2)
*buf = append(*buf, '/')
formatter(buf, day, 2)
*buf = append(*buf, ' ')
hour, min, sec := t.Clock()
formatter(buf, hour, 2)
*buf = append(*buf, ':')
formatter(buf, min, 2)
*buf = append(*buf, ':')
formatter(buf, sec, 2)
*buf = append(*buf, ' ')
} else {
fmt.Printf("Unable to unmarshal log level: %v", err)
os.Exit(2) //Fucking kill him
}
}
// Printer prints the formatted message directly to stdErr
func (l *Logger) Printer(level int, s string) error {
now := time.Now()
var line int
l.Mu.Lock()
defer l.Mu.Unlock()
l.buf = l.buf[:0]
l.formatHeader(&l.buf, now, line)
l.buf = append(l.buf, s...)
if len(s) == 0 || s[len(s)-1] != '\n' {
l.buf = append(l.buf, '\n')
}
_, err := l.Out.Write(l.buf)
return err
}
// Some line formatting stuff from Golang log stdlib file
//
// Please view https://cs.opensource.google/go/go/+/refs/tags/go1.18.3:src/log/log.go;drc=41e1d9075e428c2fc32d966b3752a3029b620e2c;l=96
//
// Cheap integer to fixed-width decimal ASCII. Give a negative width to avoid zero-padding.
func formatter(buf *[]byte, i int, wid int) {
// Assemble decimal in reverse order.
var b [20]byte
bp := len(b) - 1
for i >= 10 || wid > 1 {
wid--
q := i / 10
b[bp] = byte('0' + i - q*10)
bp--
i = q
}
// i < 10
b[bp] = byte('0' + i)
*buf = append(*buf, b[bp:]...)
}