kitty/tools/utils/mimetypes.go
2023-03-27 07:53:54 +05:30

112 lines
2.4 KiB
Go

// License: GPLv3 Copyright: 2022, Kovid Goyal, <kovid at kovidgoyal.net>
package utils
import (
"bufio"
"errors"
"fmt"
"io/fs"
"mime"
"os"
"path/filepath"
"strings"
"golang.org/x/sys/unix"
)
var _ = fmt.Print
func load_mime_file(filename string, mime_map map[string]string) error {
f, err := os.Open(filename)
if err != nil {
return err
}
defer f.Close()
scanner := bufio.NewScanner(f)
for scanner.Scan() {
fields := strings.Fields(scanner.Text())
if len(fields) <= 1 || fields[0][0] == '#' {
continue
}
mime_type := fields[0]
for _, ext := range fields[1:] {
if ext[0] == '#' {
break
}
mime_map["."+ext] = mime_type
}
}
if err := scanner.Err(); err != nil {
return err
}
return nil
}
var UserMimeMap = (&Once[map[string]string]{Run: func() map[string]string {
conf_path := filepath.Join(ConfigDir(), "mime.types")
ans := make(map[string]string, 32)
err := load_mime_file(conf_path, ans)
if err != nil && !errors.Is(err, fs.ErrNotExist) {
fmt.Fprintln(os.Stderr, "Failed to parse", conf_path, "for MIME types with error:", err)
}
return ans
}}).Get
func is_rcfile(path string) bool {
name := filepath.Base(path)
return strings.HasSuffix(name, "rc") && !strings.Contains(name, ".")
}
func GuessMimeType(filename string) string {
ext := filepath.Ext(filename)
mime_with_parameters := UserMimeMap()[ext]
if mime_with_parameters == "" {
mime_with_parameters = mime.TypeByExtension(ext)
}
if mime_with_parameters == "" {
only_once.Do(set_builtins)
mime_with_parameters = builtin_types_map[ext]
if mime_with_parameters == "" {
lext := strings.ToLower(ext)
mime_with_parameters = builtin_types_map[lext]
if mime_with_parameters == "" {
mime_with_parameters = KnownExtensions[lext]
}
if mime_with_parameters == "" && is_rcfile(filename) {
mime_with_parameters = "text/plain"
}
if mime_with_parameters == "" {
return ""
}
}
}
ans, _, err := mime.ParseMediaType(mime_with_parameters)
if err != nil {
return ""
}
return ans
}
func GuessMimeTypeWithFileSystemAccess(filename string) string {
is_dir, is_exe := false, false
s, err := os.Stat(filename)
if err == nil {
is_dir = s.IsDir()
if !is_dir && s.Mode().Perm()&0o111 != 0 && unix.Access(filename, unix.X_OK) == nil {
is_exe = true
}
}
if is_dir {
return "inode/directory"
}
mt := GuessMimeType(filename)
if mt == "" {
if is_exe {
mt = "inode/executable"
}
}
return mt
}