32 lines
895 B
Go
32 lines
895 B
Go
package oggtag
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/* oggtag is a naive implementation of OGG tag's reader that is just looking
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for certain tag names ending with an = character, e.g. artist= and title=.
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*/
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import (
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"bytes"
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"strings"
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)
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// OggGetTag is searching for a certain tag in a given buffer buf and returns
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// its value.
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//
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// It is a simple implementation that doesn't parse a header and instead just
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// looking for a certain tag preceded with three zero bytes and ends with
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// an = character.
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func OggGetTag(buf []byte, tag string) string {
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tagIdx := bytes.Index(buf, append([]byte{0, 0, 0}, (tag+"=")...))
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if tagIdx == -1 {
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tagIdx = bytes.Index(buf, append([]byte{0, 0, 0}, (strings.ToUpper(tag)+"=")...))
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if tagIdx == -1 {
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return ""
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}
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}
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tagIdx += 3
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tagNameLen := len(tag) + 1
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valStart := tagIdx + tagNameLen
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valLen := int(buf[tagIdx-4]) - tagNameLen
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return string(buf[valStart : valStart+valLen])
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}
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