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[v6,11/16] bsd-user: Create special-errno.h

Message ID 20211123173759.1383510-12-richard.henderson@linaro.org
State New
Headers show
Series linux-user: simplify safe signal handling | expand

Commit Message

Richard Henderson Nov. 23, 2021, 5:37 p.m. UTC 
Pull the internal errno used by qemu internally its own
header file, for use by safe-syscall.S.

Reviewed-by: Warner Losh <imp@bsdimp.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 bsd-user/errno_defs.h    |  6 +++++-
 bsd-user/special-errno.h | 24 ++++++++++++++++++++++++
 2 files changed, 29 insertions(+), 1 deletion(-)
 create mode 100644 bsd-user/special-errno.h
diff mbox series

Patch

diff --git a/bsd-user/errno_defs.h b/bsd-user/errno_defs.h
index 141e08456c..73cfa24b7f 100644
--- a/bsd-user/errno_defs.h
+++ b/bsd-user/errno_defs.h
@@ -151,6 +151,10 @@ 
 /* Internal errors: */
 #define TARGET_EJUSTRETURN      254             /* Just return without modifing regs */
 #define TARGET_ERESTART         255             /* Restart syscall */
-#define QEMU_ERESTARTSYS        TARGET_ERESTART
+
+#include "special-errno.h"
+
+_Static_assert(TARGET_ERESTART == QEMU_ERESTARTSYS,
+               "TARGET_ERESTART and QEMU_ERESTARTSYS expected to match");
 
 #endif /* !  _ERRNO_DEFS_H_ */
diff --git a/bsd-user/special-errno.h b/bsd-user/special-errno.h
new file mode 100644
index 0000000000..03599d9b5a
--- /dev/null
+++ b/bsd-user/special-errno.h
@@ -0,0 +1,24 @@ 
+/* SPDX-License-Identifier: BSD-3-Clause */
+/*
+ * QEMU internal errno values for implementing user-only POSIX.
+ *
+ *  Copyright (c) 2021 Linaro, Ltd.
+ */
+
+#ifndef SPECIAL_ERRNO_H
+#define SPECIAL_ERRNO_H
+
+/*
+ * All of these are QEMU internal, not visible to the guest.
+ * They should be chosen so as to not overlap with any host
+ * or guest errno.
+ */
+
+/*
+ * This is returned when a system call should be restarted, to tell the
+ * main loop that it should wind the guest PC backwards so it will
+ * re-execute the syscall after handling any pending signals.
+ */
+#define QEMU_ERESTARTSYS  255
+
+#endif /* SPECIAL_ERRNO_H */