xnu-3248.60.10.tar.gz

[apple/xnu.git] / libsyscall / custom / errno.c

diff --git a/libsyscall/custom/errno.c b/libsyscall/custom/errno.c
index 58da2c114e1df471f2a6d097b69777e262717b7e..86f754a6518b12d3331a323e0ea580fa3f5a7138 100644 (file)
--- a/libsyscall/custom/errno.c
+++ b/libsyscall/custom/errno.c
@@ -26,4 +26,54 @@
  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  */
 
+#include <TargetConditionals.h>
+#include <stddef.h>
+#include <stdint.h>
+#include "tsd.h"
+
+/*
+ * cerror takes the return value of the syscall, being non-zero, and
+ * stores it in errno. It needs to return -1 to indicate failure but
+ * 64-bit platforms need to ensure that possible 128-bit wide return
+ * values are also properly set.
+ */
+#ifdef __LP64__
+typedef unsigned __int128 cerror_return_t;
+#else
+typedef uint64_t cerror_return_t;
+#endif
+
+extern void _pthread_exit_if_canceled(int error);
+
+#undef errno
 int errno;
+
+int *
+__error(void)
+{
+       void *ptr = _os_tsd_get_direct(__TSD_ERRNO);
+       if (ptr != NULL) {
+               return (int*)ptr;
+       }
+       return &errno;
+}
+
+__attribute__((noinline))
+cerror_return_t
+cerror_nocancel(int err)
+{
+       errno = err;
+       int *tsderrno = (int*)_os_tsd_get_direct(__TSD_ERRNO);
+       if (tsderrno) {
+               *tsderrno = err;
+       }
+       return -1;
+}
+
+__attribute__((noinline))
+cerror_return_t
+cerror(int err)
+{
+       _pthread_exit_if_canceled(err);
+       return cerror_nocancel(err);
+}