Created student weenix repository

1 files changed, 26 insertions, 0 deletions

diff --git a/user/include/weenix/trap.h b/user/include/weenix/trap.h
new file mode 100644
index 0000000..fade1eb
--- /dev/null
+++ b/user/include/weenix/trap.h
@@ -0,0 +1,26 @@
+#pragma once
+
+#include "errno.h"
+#include "stddef.h"
+#include "sys/types.h"
+#include "weenix/syscall.h"
+
+#define TRAP_INTR_STRING QUOTE(INTR_SYSCALL)
+
+/* ssize_t will be 32 bits or 64 bits wide as appropriate.
+   args are passed via %(r/e)ax and %(r/e)dx, so they need
+   to be the size of a register.  */
+
+static inline ssize_t trap(ssize_t num, ssize_t arg)
+{
+    ssize_t ret;
+    __asm__ volatile("int $" TRAP_INTR_STRING
+                     : "=a"(ret)
+                     : "a"(num), "d"(arg));
+
+    /* Copy in errno */
+    __asm__ volatile("int $" TRAP_INTR_STRING
+                     : "=a"(errno)
+                     : "a"(SYS_errno));
+    return ret;
+}