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https://github.com/tinygo-org/tinygo.git
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Ayke van Laethem
aa63f26f36
This allows the binaries to run on Windows XP, without needing any extra DLLs. Tested in an x86 Windows XP SP3 virtual machine.
41 lines
1.0 KiB
Go
41 lines
1.0 KiB
Go
package rand
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import (
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"errors"
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"unsafe"
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)
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func init() {
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Reader = &reader{}
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}
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type reader struct {
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}
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var errRandom = errors.New("failed to obtain random data from rand_s")
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func (r *reader) Read(b []byte) (n int, err error) {
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if len(b) == 0 {
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return
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}
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// Use the old RtlGenRandom, introduced in Windows XP.
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// Even though the documentation says it is deprecated, it is widely used
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// and probably won't go away anytime soon.
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// See for example: https://github.com/golang/go/issues/33542
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// For Windows 7 and newer, we might switch to ProcessPrng in the future
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// (which is a documented function and might be a tiny bit faster).
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ok := libc_RtlGenRandom(unsafe.Pointer(&b[0]), len(b))
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if !ok {
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return 0, errRandom
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}
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return len(b), nil
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}
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// This function is part of advapi32.dll, and is called SystemFunction036 for
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// some reason. It's available on Windows XP and newer.
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// See: https://learn.microsoft.com/en-us/windows/win32/api/ntsecapi/nf-ntsecapi-rtlgenrandom
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//
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//export SystemFunction036
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func libc_RtlGenRandom(buf unsafe.Pointer, len int) bool
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