mirror of https://github.com/perkeep/perkeep.git
50 lines
1.1 KiB
Go
50 lines
1.1 KiB
Go
package main
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import (
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"http"
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"regexp"
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"strconv"
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)
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// Default is {0, -1} to read all of a file.
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type requestedRange struct {
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SkipBytes int64
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LimitBytes int64 // or -1 to read all
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}
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func (rr *requestedRange) IsWholeFile() bool {
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return rr.SkipBytes == 0 && rr.LimitBytes == -1;
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}
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var wholeRange = &requestedRange{0, -1}
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var rangePattern = regexp.MustCompile(`bytes=([0-9]+)-([0-9]*)`)
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func getRequestedRange(req *http.Request) *requestedRange {
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rrange, ok := req.Header["Range"]
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if !ok {
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return wholeRange
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}
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return getRequestedRangeFromString(rrange)
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}
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func getRequestedRangeFromString(rrange string) *requestedRange {
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matches := rangePattern.FindStringSubmatch(rrange)
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if len(matches) == 0 {
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return wholeRange;
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}
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skipBytes, _ := strconv.Atoi64(matches[1])
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lastByteInclusive := int64(-1)
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if len(matches[2]) > 0 {
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lastByteInclusive, _ = strconv.Atoi64(matches[2])
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}
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limitBytes := int64(-1)
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if lastByteInclusive != -1 {
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limitBytes = lastByteInclusive - skipBytes + 1
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if limitBytes < 0 {
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limitBytes = 0
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}
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}
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return &requestedRange{skipBytes, limitBytes}
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}
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