diff options
Diffstat (limited to 'src/mime/type_unix.go')
-rw-r--r-- | src/mime/type_unix.go | 126 |
1 files changed, 126 insertions, 0 deletions
diff --git a/src/mime/type_unix.go b/src/mime/type_unix.go new file mode 100644 index 0000000..649d900 --- /dev/null +++ b/src/mime/type_unix.go @@ -0,0 +1,126 @@ +// Copyright 2010 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +//go:build unix || (js && wasm) + +package mime + +import ( + "bufio" + "os" + "strings" +) + +func init() { + osInitMime = initMimeUnix +} + +// See https://specifications.freedesktop.org/shared-mime-info-spec/shared-mime-info-spec-0.21.html +// for the FreeDesktop Shared MIME-info Database specification. +var mimeGlobs = []string{ + "/usr/local/share/mime/globs2", + "/usr/share/mime/globs2", +} + +// Common locations for mime.types files on unix. +var typeFiles = []string{ + "/etc/mime.types", + "/etc/apache2/mime.types", + "/etc/apache/mime.types", + "/etc/httpd/conf/mime.types", +} + +func loadMimeGlobsFile(filename string) error { + f, err := os.Open(filename) + if err != nil { + return err + } + defer f.Close() + + scanner := bufio.NewScanner(f) + for scanner.Scan() { + // Each line should be of format: weight:mimetype:glob[:morefields...] + fields := strings.Split(scanner.Text(), ":") + if len(fields) < 3 || len(fields[0]) < 1 || len(fields[2]) < 3 { + continue + } else if fields[0][0] == '#' || fields[2][0] != '*' || fields[2][1] != '.' { + continue + } + + extension := fields[2][1:] + if strings.ContainsAny(extension, "?*[") { + // Not a bare extension, but a glob. Ignore for now: + // - we do not have an implementation for this glob + // syntax (translation to path/filepath.Match could + // be possible) + // - support for globs with weight ordering would have + // performance impact to all lookups to support the + // rarely seen glob entries + // - trying to match glob metacharacters literally is + // not useful + continue + } + if _, ok := mimeTypes.Load(extension); ok { + // We've already seen this extension. + // The file is in weight order, so we keep + // the first entry that we see. + continue + } + + setExtensionType(extension, fields[1]) + } + if err := scanner.Err(); err != nil { + panic(err) + } + return nil +} + +func loadMimeFile(filename string) { + f, err := os.Open(filename) + if err != nil { + return + } + defer f.Close() + + scanner := bufio.NewScanner(f) + for scanner.Scan() { + fields := strings.Fields(scanner.Text()) + if len(fields) <= 1 || fields[0][0] == '#' { + continue + } + mimeType := fields[0] + for _, ext := range fields[1:] { + if ext[0] == '#' { + break + } + setExtensionType("."+ext, mimeType) + } + } + if err := scanner.Err(); err != nil { + panic(err) + } +} + +func initMimeUnix() { + for _, filename := range mimeGlobs { + if err := loadMimeGlobsFile(filename); err == nil { + return // Stop checking more files if mimetype database is found. + } + } + + // Fallback if no system-generated mimetype database exists. + for _, filename := range typeFiles { + loadMimeFile(filename) + } +} + +func initMimeForTests() map[string]string { + mimeGlobs = []string{""} + typeFiles = []string{"testdata/test.types"} + return map[string]string{ + ".T1": "application/test", + ".t2": "text/test; charset=utf-8", + ".png": "image/png", + } +} |