M4andCursor
6b6c13c933
Reduce idle CPU (cheap PollUI, binary cache, logbuf cap, DOM fingerprint), speed ping/AWG HostPort, CopyBuffer pool; ship arm64 build and update notes. Co-authored-by: Cursor <cursoragent@cursor.com>
60 lines
997 B
Go
60 lines
997 B
Go
package logbuf
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import (
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"bytes"
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"sync"
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)
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const DefaultMax = 256 << 10 // 256 KiB
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// Buffer is a concurrency-safe, size-capped bytes.Buffer replacement for engine stderr.
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type Buffer struct {
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mu sync.Mutex
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buf bytes.Buffer
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max int
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}
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func New(max int) *Buffer {
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if max <= 0 {
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max = DefaultMax
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}
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return &Buffer{max: max}
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}
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func (b *Buffer) Write(p []byte) (int, error) {
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if b == nil {
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return len(p), nil
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}
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b.mu.Lock()
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defer b.mu.Unlock()
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if b.buf.Len()+len(p) > b.max {
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// Drop oldest half to keep recent diagnostics.
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keep := b.buf.Bytes()
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if len(keep) > b.max/2 {
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keep = keep[len(keep)-b.max/2:]
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}
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b.buf.Reset()
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_, _ = b.buf.Write(keep)
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_, _ = b.buf.WriteString("\n… log truncated …\n")
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}
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return b.buf.Write(p)
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}
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func (b *Buffer) String() string {
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if b == nil {
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return ""
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}
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b.mu.Lock()
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defer b.mu.Unlock()
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return b.buf.String()
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}
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func (b *Buffer) Len() int {
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if b == nil {
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return 0
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}
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b.mu.Lock()
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defer b.mu.Unlock()
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return b.buf.Len()
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}
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