48 lines
1.0 KiB
Go
48 lines
1.0 KiB
Go
package syscall
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import (
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"github.com/goplus/llgo/runtime/internal/clite/byteorder"
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"github.com/goplus/llgo/runtime/internal/clite/goarch"
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)
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// readInt returns the size-bytes unsigned integer in native byte order at offset off.
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func readInt(b []byte, off, size uintptr) (u uint64, ok bool) {
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if len(b) < int(off+size) {
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return 0, false
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}
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if goarch.BigEndian {
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return readIntBE(b[off:], size), true
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}
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return readIntLE(b[off:], size), true
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}
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func readIntBE(b []byte, size uintptr) uint64 {
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switch size {
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case 1:
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return uint64(b[0])
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case 2:
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return uint64(byteorder.BEUint16(b))
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case 4:
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return uint64(byteorder.BEUint32(b))
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case 8:
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return uint64(byteorder.BEUint64(b))
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default:
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panic("syscall: readInt with unsupported size")
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}
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}
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func readIntLE(b []byte, size uintptr) uint64 {
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switch size {
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case 1:
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return uint64(b[0])
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case 2:
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return uint64(byteorder.LEUint16(b))
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case 4:
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return uint64(byteorder.LEUint32(b))
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case 8:
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return uint64(byteorder.LEUint64(b))
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default:
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panic("syscall: readInt with unsupported size")
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}
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}
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