summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--configure.ac6
-rw-r--r--src/xshmfence_alloc.c50
2 files changed, 48 insertions, 8 deletions
diff --git a/configure.ac b/configure.ac
index ddf63dc..84b49de 100644
--- a/configure.ac
+++ b/configure.ac
@@ -89,6 +89,12 @@ AC_SUBST([XPROTO_CFLAGS])
CFLAGS="$CFLAGS $XPROTO_CFLAGS"
+AC_CHECK_FUNCS(memfd_create)
+
+AC_CHECK_DECLS([__NR_memfd_create], [], [], [[#include <asm/unistd.h>]])
+
+AC_CHECK_HEADERS([sys/memfd.h], [AC_DEFINE([HAVE_MEMFD_H], 1, [Has sys/memfd.h header])])
+
AC_ARG_ENABLE(visibility, AC_HELP_STRING([--enable-visibility], [Enable symbol visibility (default: auto)]),
[SYMBOL_VISIBILITY=$enableval],
[SYMBOL_VISIBILITY=auto])
diff --git a/src/xshmfence_alloc.c b/src/xshmfence_alloc.c
index 58416cd..05cf953 100644
--- a/src/xshmfence_alloc.c
+++ b/src/xshmfence_alloc.c
@@ -26,6 +26,34 @@
#include "xshmfenceint.h"
+#if !HAVE_MEMFD_CREATE
+#if HAVE_DECL___NR_MEMFD_CREATE
+#include <asm/unistd.h>
+static int memfd_create(const char *name,
+ unsigned int flags)
+{
+ return syscall(__NR_memfd_create, name, flags);
+}
+#define HAVE_MEMFD_CREATE 1
+#endif
+#endif
+
+#if HAVE_MEMFD_CREATE
+
+/* Get defines for the memfd_create syscall, using the
+ * header if available, or just defining the constants otherwise
+ */
+
+#if HAVE_MEMFD_H
+#include <sys/memfd.h>
+#else
+/* flags for memfd_create(2) (unsigned int) */
+#define MFD_CLOEXEC 0x0001U
+#define MFD_ALLOW_SEALING 0x0002U
+#endif
+
+#endif
+
/**
* xshmfence_alloc_shm:
*
@@ -41,16 +69,22 @@ xshmfence_alloc_shm(void)
char template[] = SHMDIR "/shmfd-XXXXXX";
int fd;
-#ifdef O_TMPFILE
- fd = open(SHMDIR, O_TMPFILE|O_RDWR|O_CLOEXEC|O_EXCL, 0666);
+#if HAVE_MEMFD_CREATE
+ fd = memfd_create("xshmfence", MFD_CLOEXEC|MFD_ALLOW_SEALING);
if (fd < 0)
#endif
- {
- fd = mkstemp(template);
- if (fd < 0)
- return fd;
- unlink(template);
- }
+ {
+#ifdef O_TMPFILE
+ fd = open(SHMDIR, O_TMPFILE|O_RDWR|O_CLOEXEC|O_EXCL, 0666);
+ if (fd < 0)
+#endif
+ {
+ fd = mkstemp(template);
+ if (fd < 0)
+ return fd;
+ unlink(template);
+ }
+ }
if (ftruncate(fd, sizeof (struct xshmfence)) < 0) {
close(fd);
return -1;