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-rw-r--r--Utilities/cmlibuv/src/unix/random-getrandom.c88
1 files changed, 88 insertions, 0 deletions
diff --git a/Utilities/cmlibuv/src/unix/random-getrandom.c b/Utilities/cmlibuv/src/unix/random-getrandom.c
new file mode 100644
index 0000000..bcc9408
--- /dev/null
+++ b/Utilities/cmlibuv/src/unix/random-getrandom.c
@@ -0,0 +1,88 @@
+/* Copyright libuv contributors. All rights reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#include "uv.h"
+#include "internal.h"
+
+#ifdef __linux__
+
+#include "linux-syscalls.h"
+
+#define uv__random_getrandom_init() 0
+
+#else /* !__linux__ */
+
+#include <stddef.h>
+#include <dlfcn.h>
+
+typedef ssize_t (*uv__getrandom_cb)(void *, size_t, unsigned);
+
+static uv__getrandom_cb uv__getrandom;
+static uv_once_t once = UV_ONCE_INIT;
+
+static void uv__random_getrandom_init_once(void) {
+ uv__getrandom = (uv__getrandom_cb) dlsym(RTLD_DEFAULT, "getrandom");
+}
+
+static int uv__random_getrandom_init(void) {
+ uv_once(&once, uv__random_getrandom_init_once);
+
+ if (uv__getrandom == NULL)
+ return UV_ENOSYS;
+
+ return 0;
+}
+
+#endif /* !__linux__ */
+
+int uv__random_getrandom(void* buf, size_t buflen) {
+ ssize_t n;
+ size_t pos;
+ int rc;
+
+ rc = uv__random_getrandom_init();
+ if (rc != 0)
+ return rc;
+
+ for (pos = 0; pos != buflen; pos += n) {
+ do {
+ n = buflen - pos;
+
+ /* Most getrandom() implementations promise that reads <= 256 bytes
+ * will always succeed and won't be interrupted by signals.
+ * It's therefore useful to split it up in smaller reads because
+ * one big read may, in theory, continuously fail with EINTR.
+ */
+ if (n > 256)
+ n = 256;
+
+ n = uv__getrandom((char *) buf + pos, n, 0);
+ } while (n == -1 && errno == EINTR);
+
+ if (n == -1)
+ return UV__ERR(errno);
+
+ if (n == 0)
+ return UV_EIO;
+ }
+
+ return 0;
+}