mirror of https://github.com/perkeep/perkeep.git
45 lines
1.1 KiB
Go
45 lines
1.1 KiB
Go
/*
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Copyright 2011 Google Inc.
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Licensed under the Apache License, Version 2.0 (the "License");
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you may not use this file except in compliance with the License.
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nYou may obtain a copy of the License at
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http://www.apache.org/licenses/LICENSE-2.0
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Unless required by applicable law or agreed to in writing, software
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distributed under the License is distributed on an "AS IS" BASIS,
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WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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See the License for the specific language governing permissions and
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limitations under the License.
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*/
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package magic
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import (
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"bytes"
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)
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type prefixEntry struct {
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prefix []byte
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mtype string
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}
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var prefixTable = []prefixEntry{
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{[]byte("\xff\xd8\xff\xe1"), "image/jpeg"},
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{[]byte("\xff\xd8\xff\xe0"), "image/jpeg"},
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{[]byte{137, 'P', 'N', 'G', '\r', '\n', 26, 10}, "image/png"},
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}
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// Returns the emptry string if unknown.
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func MimeType(hdr []byte) string {
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hlen := len(hdr)
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for _, pte := range prefixTable {
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plen := len(pte.prefix)
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if hlen > plen && bytes.Equal(hdr[:plen], pte.prefix) {
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return pte.mtype
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}
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}
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return ""
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}
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