42 lines
1.4 KiB
Go
42 lines
1.4 KiB
Go
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// GoToSocial
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// Copyright (C) GoToSocial Authors admin@gotosocial.org
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// SPDX-License-Identifier: AGPL-3.0-or-later
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//
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// This program is free software: you can redistribute it and/or modify
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// it under the terms of the GNU Affero General Public License as published by
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// the Free Software Foundation, either version 3 of the License, or
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// (at your option) any later version.
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//
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// This program is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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// GNU Affero General Public License for more details.
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//
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// You should have received a copy of the GNU Affero General Public License
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// along with this program. If not, see <http://www.gnu.org/licenses/>.
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package media
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// newHdrBuf returns a buffer of suitable size to
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// read bytes from a file header or magic number.
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//
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// File header is *USUALLY* 261 bytes at the start
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// of a file; magic number can be much less than
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// that (just a few bytes).
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//
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// To cover both cases, this function returns a buffer
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// suitable for whichever is smallest: the first 261
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// bytes of the file, or the whole file.
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//
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// See:
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//
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// - https://en.wikipedia.org/wiki/File_format#File_header
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// - https://github.com/h2non/filetype.
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func newHdrBuf(fileSize int) []byte {
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bufSize := 261
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if fileSize > 0 && fileSize < bufSize {
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bufSize = fileSize
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}
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return make([]byte, bufSize)
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}
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