From a9ea218e7e119d7d7d050156835d4e16f41d0a6c Mon Sep 17 00:00:00 2001
From: Sergey Kandaurov <pluknet@nginx.com>
Date: Thu, 24 May 2018 20:35:47 +0300
Subject: [PATCH] Using getrandom() libc interface, SYS_getrandom fixes.

The interface is available since Glibc 2.25, and FreeBSD 12.0.
---
 auto/unix        | 34 ++++++++++++++++++++++++++++++----
 src/nxt_random.c |  8 ++++++--
 src/nxt_unix.h   | 10 ++++++----
 3 files changed, 42 insertions(+), 10 deletions(-)

diff --git a/auto/unix b/auto/unix
index acacce0d..b6763852 100644
--- a/auto/unix
+++ b/auto/unix
@@ -3,25 +3,51 @@
 # Copyright (C) NGINX, Inc.
 
 
-# Linux 3.17 getrandom().
+# getrandom().
 
 nxt_feature="getrandom()"
 nxt_feature_name=NXT_HAVE_GETRANDOM
-nxt_feature_run=
+nxt_feature_run=yes
 nxt_feature_incs=
 nxt_feature_libs=
-nxt_feature_test="#include <linux/random.h>
+nxt_feature_test="#include <unistd.h>
+                  #include <sys/random.h>
 
                   int main() {
                       char  buf[4];
 
-                      (void) getrandom(buf, 4, 0);
+                      if (getrandom(buf, 4, 0) < 0) {
+                          return 1;
+                      }
 
                       return 0;
                   }"
 . auto/feature
 
 
+if [ $nxt_found = no ]; then
+
+    # Linux 3.17 SYS_getrandom.
+
+    nxt_feature="SYS_getrandom in Linux"
+    nxt_feature_name=NXT_HAVE_LINUX_SYS_GETRANDOM
+    nxt_feature_test="#include <unistd.h>
+                      #include <sys/syscall.h>
+                      #include <linux/random.h>
+
+                      int main() {
+                          char  buf[4];
+
+                          if (syscall(SYS_getrandom, buf, 4, 0) < 0) {
+                              return 1;
+                          }
+
+                          return 0;
+                      }"
+    . auto/feature
+fi
+
+
 nxt_feature="ucontext"
 nxt_feature_name=NXT_HAVE_UCONTEXT
 nxt_feature_run=
diff --git a/src/nxt_random.c b/src/nxt_random.c
index 3dde1f15..27387b1f 100644
--- a/src/nxt_random.c
+++ b/src/nxt_random.c
@@ -62,9 +62,13 @@ nxt_random_stir(nxt_random_t *r)
 
 #if (NXT_HAVE_GETRANDOM)
 
-    /* Linux 3.17 getrandom(). */
+    n = getrandom(&key, NXT_RANDOM_KEY_SIZE, 0);
 
-    n = getrandom(key, NXT_RANDOM_KEY_SIZE, 0);
+#elif (NXT_HAVE_LINUX_SYS_GETRANDOM)
+
+    /* Linux 3.17 SYS_getrandom. */
+
+    n = syscall(SYS_getrandom, &key, NXT_RANDOM_KEY_SIZE, 0);
 
 #endif
 
diff --git a/src/nxt_unix.h b/src/nxt_unix.h
index d61f00bc..33e9f247 100644
--- a/src/nxt_unix.h
+++ b/src/nxt_unix.h
@@ -32,10 +32,6 @@
 #include <malloc.h>                 /* malloc_usable_size(). */
 #include <sys/syscall.h>            /* syscall(SYS_gettid). */
 
-#if (NXT_GETRANDOM)
-#include <linux/random.h>           /* getrandom(). */
-#endif
-
 #if (__GLIBC__ >= 2 && __GLIBC_MINOR__ >= 4)
 /*
  * POSIX semaphores using NPTL atomic/futex operations
@@ -234,6 +230,12 @@
 #include <sys/sendfile.h>
 #endif
 
+#if (NXT_HAVE_GETRANDOM)
+#include <sys/random.h>             /* getrandom(). */
+#elif (NXT_HAVE_LINUX_SYS_GETRANDOM)
+#include <linux/random.h>           /* SYS_getrandom. */
+#endif
+
 
 #if (NXT_TEST_BUILD)
 #include <nxt_test_build.h>