1 files changed, 134 insertions, 0 deletions
diff --git a/modules/log/flags.go b/modules/log/flags.go
new file mode 100644
index 00000000..f025159d
--- /dev/null
+++ b/modules/log/flags.go
@@ -0,0 +1,134 @@
+// Copyright 2023 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package log
+
+import (
+	"sort"
+	"strings"
+
+	"code.gitea.io/gitea/modules/json"
+)
+
+// These flags define which text to prefix to each log entry generated
+// by the Logger. Bits are or'ed together to control what's printed.
+// There is no control over the order they appear (the order listed
+// here) or the format they present (as described in the comments).
+// The prefix is followed by a colon only if more than time is stated
+// is specified. For example, flags Ldate | Ltime
+// produce, 2009/01/23 01:23:23 message.
+// The standard is:
+// 2009/01/23 01:23:23 ...a/logger/c/d.go:23:runtime.Caller() [I]: message
+const (
+	Ldate          uint32 = 1 << iota // the date in the local time zone: 2009/01/23
+	Ltime                             // the time in the local time zone: 01:23:23
+	Lmicroseconds                     // microsecond resolution: 01:23:23.123123.  assumes Ltime.
+	Llongfile                         // full file name and line number: /a/logger/c/d.go:23
+	Lshortfile                        // final file name element and line number: d.go:23. overrides Llongfile
+	Lfuncname                         // function name of the caller: runtime.Caller()
+	Lshortfuncname                    // last part of the function name
+	LUTC                              // if Ldate or Ltime is set, use UTC rather than the local time zone
+	Llevelinitial                     // Initial character of the provided level in brackets, eg. [I] for info
+	Llevel                            // Provided level in brackets [INFO]
+	Lgopid                            // the Goroutine-PID of the context
+
+	Lmedfile  = Lshortfile | Llongfile                                    // last 20 characters of the filename
+	LstdFlags = Ldate | Ltime | Lmedfile | Lshortfuncname | Llevelinitial // default
+)
+
+const Ldefault = LstdFlags
+
+type Flags struct {
+	defined bool
+	flags   uint32
+}
+
+var flagFromString = map[string]uint32{
+	"date":          Ldate,
+	"time":          Ltime,
+	"microseconds":  Lmicroseconds,
+	"longfile":      Llongfile,
+	"shortfile":     Lshortfile,
+	"funcname":      Lfuncname,
+	"shortfuncname": Lshortfuncname,
+	"utc":           LUTC,
+	"levelinitial":  Llevelinitial,
+	"level":         Llevel,
+	"gopid":         Lgopid,
+
+	"medfile":  Lmedfile,
+	"stdflags": LstdFlags,
+}
+
+var flagComboToString = []struct {
+	flag uint32
+	name string
+}{
+	// name with more bits comes first
+	{LstdFlags, "stdflags"},
+	{Lmedfile, "medfile"},
+
+	{Ldate, "date"},
+	{Ltime, "time"},
+	{Lmicroseconds, "microseconds"},
+	{Llongfile, "longfile"},
+	{Lshortfile, "shortfile"},
+	{Lfuncname, "funcname"},
+	{Lshortfuncname, "shortfuncname"},
+	{LUTC, "utc"},
+	{Llevelinitial, "levelinitial"},
+	{Llevel, "level"},
+	{Lgopid, "gopid"},
+}
+
+func (f Flags) Bits() uint32 {
+	if !f.defined {
+		return Ldefault
+	}
+	return f.flags
+}
+
+func (f Flags) String() string {
+	flags := f.Bits()
+	var flagNames []string
+	for _, it := range flagComboToString {
+		if flags&it.flag == it.flag {
+			flags &^= it.flag
+			flagNames = append(flagNames, it.name)
+		}
+	}
+	if len(flagNames) == 0 {
+		return "none"
+	}
+	sort.Strings(flagNames)
+	return strings.Join(flagNames, ",")
+}
+
+func (f *Flags) UnmarshalJSON(bytes []byte) error {
+	var s string
+	if err := json.Unmarshal(bytes, &s); err != nil {
+		return err
+	}
+	*f = FlagsFromString(s)
+	return nil
+}
+
+func (f Flags) MarshalJSON() ([]byte, error) {
+	return []byte(`"` + f.String() + `"`), nil
+}
+
+func FlagsFromString(from string, def ...uint32) Flags {
+	from = strings.TrimSpace(from)
+	if from == "" && len(def) > 0 {
+		return Flags{defined: true, flags: def[0]}
+	}
+	flags := uint32(0)
+	for _, flag := range strings.Split(strings.ToLower(from), ",") {
+		flags |= flagFromString[strings.TrimSpace(flag)]
+	}
+	return Flags{defined: true, flags: flags}
+}
+
+func FlagsFromBits(flags uint32) Flags {
+	return Flags{defined: true, flags: flags}
+}