62 lines
1.4 KiB
Go
62 lines
1.4 KiB
Go
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// 23 february 2015
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package ui
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// Go pointers cannot be passed to C safely.
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// The Go runtime will move them around, tripping C up.
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// However, C pointers don't have this problem.
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// Solution: use the C pointer to get the Go object needed!
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import (
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"fmt"
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"sync"
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)
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var (
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ids map[uintptr]interface{}
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idsLock sync.Mutex
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)
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func getGoObject(cptr uintptr) interface{} {
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idsLock.Lock()
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defer idsLock.Unlock()
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if i, ok := ids[cptr]; ok {
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return i
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}
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panic(fmt.Errorf("[BUG in package ui; report to andlabs immediately] C pointer %p not associated with Go object in package ui", cptr))
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}
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func associateGoObject(cptr uintptr, goobj interface{}) {
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idsLock.Lock()
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defer idsLock.Unlock()
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if i, ok := ids[cptr]; ok {
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panic(fmt.Errorf("[BUG in package ui; report to andlabs immediately] C pointer %p already associated with Go object of type %T but we want to associate it with Go object of type %T", cptr, i, goobj))
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}
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ids[cptr] = goobj
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}
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func disassociateGoObject(cptr uintptr) {
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idsLock.Lock()
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defer idsLock.Unlock()
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if _, ok := ids[cptr]; !ok {
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panic(fmt.Errorf("[BUG in package ui; report to andlabs immediately] C pointer %p not associated with any Go object but we want to disassociate it", cptr))
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}
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delete(ids, cptr)
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}
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func idsHandler(req *request) bool {
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switch req.id {
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case reqObjectDestroyed:
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disassociateGoObject(req.ptr)
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return true
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}
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return false
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}
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func init() {
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interopHandlers = append(interopHandlers, idsHandler)
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}
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