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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-16 19:23:18 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-16 19:23:18 +0000
commit43a123c1ae6613b3efeed291fa552ecd909d3acf (patch)
treefd92518b7024bc74031f78a1cf9e454b65e73665 /src/internal/syscall/unix/getrandom.go
parentInitial commit. (diff)
downloadgolang-1.20-43a123c1ae6613b3efeed291fa552ecd909d3acf.tar.xz
golang-1.20-43a123c1ae6613b3efeed291fa552ecd909d3acf.zip
Adding upstream version 1.20.14.upstream/1.20.14upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/internal/syscall/unix/getrandom.go')
-rw-r--r--src/internal/syscall/unix/getrandom.go39
1 files changed, 39 insertions, 0 deletions
diff --git a/src/internal/syscall/unix/getrandom.go b/src/internal/syscall/unix/getrandom.go
new file mode 100644
index 0000000..a665933
--- /dev/null
+++ b/src/internal/syscall/unix/getrandom.go
@@ -0,0 +1,39 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build dragonfly || freebsd || linux
+
+package unix
+
+import (
+ "sync/atomic"
+ "syscall"
+ "unsafe"
+)
+
+var getrandomUnsupported int32 // atomic
+
+// GetRandomFlag is a flag supported by the getrandom system call.
+type GetRandomFlag uintptr
+
+// GetRandom calls the getrandom system call.
+func GetRandom(p []byte, flags GetRandomFlag) (n int, err error) {
+ if len(p) == 0 {
+ return 0, nil
+ }
+ if atomic.LoadInt32(&getrandomUnsupported) != 0 {
+ return 0, syscall.ENOSYS
+ }
+ r1, _, errno := syscall.Syscall(getrandomTrap,
+ uintptr(unsafe.Pointer(&p[0])),
+ uintptr(len(p)),
+ uintptr(flags))
+ if errno != 0 {
+ if errno == syscall.ENOSYS {
+ atomic.StoreInt32(&getrandomUnsupported, 1)
+ }
+ return 0, errno
+ }
+ return int(r1), nil
+}