Branch imports for masters.

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1 files changed, 90 insertions, 0 deletions

diff --git a/mps/code/protli.c b/mps/code/protli.c
new file mode 100644
index 00000000000..20c9dfc5b55
--- /dev/null
+++ b/mps/code/protli.c
@@ -0,0 +1,90 @@
+/*  impl.c.protli: PROTECTION FOR LINUX
+ *
+ *  $HopeName: $
+ *  Copyright (C) 1995,1999 Harlequin Group, all rights reserved
+ *
+ */
+
+#include "mpm.h"
+
+#ifndef MPS_OS_LI
+#error "protli.c is Linux specific, but MPS_OS_LI is not set"
+#endif
+#ifndef PROTECTION
+#error "protli.c implements protection, but PROTECTION is not set"
+#endif
+
+#include <limits.h>
+#include <stddef.h>
+#include <stdlib.h>
+#include <sys/mman.h>
+
+SRCID(protli, "$HopeName: $");
+
+
+/* ProtSet -- set protection
+ *
+ * This is just a thin veneer on top of mprotect(2).
+ */
+
+void ProtSet(Addr base, Addr limit, AccessSet mode)
+{
+  int flags;
+  int res;
+
+  AVER(sizeof(int) == sizeof(Addr));   /* should be redundant; will fail on Alpha */
+  AVER(base < limit);
+  AVER(base != 0);
+  AVER(AddrOffset(base, limit) <= INT_MAX);     /* should be redundant */
+
+#if 0
+  /* .flags.trouble: This less strict version of flags (which allows write
+   * access unless explicitly told not to) caused mmqa test 37 to fail.
+   * This might be a bug in MPS, so for now we go with the stricter
+   * version that matches the Win32 implementation. */
+  flags = 0;
+  if((mode & AccessREAD) == 0)
+    flags |= PROT_READ | PROT_EXEC;
+  if((mode & AccessWRITE) == 0)
+    flags |= PROT_WRITE;
+#endif
+  flags = PROT_READ | PROT_WRITE | PROT_EXEC;
+  if((mode & AccessWRITE) != 0)
+    flags = PROT_READ | PROT_EXEC;
+  if((mode & AccessREAD) != 0)
+    flags = 0;
+
+  res = mprotect((void *)base, (size_t)AddrOffset(base, limit), flags);
+  AVER(res == 0);
+}
+
+
+/* ProtSync -- synchronize protection settings with hardware
+ *
+ * This does nothing under Linux.
+ */
+
+void ProtSync(Arena arena)
+{
+  NOOP;
+}
+
+
+
+/* ProtTramp -- protection trampoline
+ *
+ * The protection trampoline is trivial under Linux, as there is nothing
+ * that needs to be done in the dynamic context of the mutator in order
+ * to catch faults.  (Contrast this with Win32 Structured Exception
+ * Handling.)
+ */
+
+void ProtTramp(void **resultReturn, void *(*f)(void *, size_t),
+               void *p, size_t s)
+{
+  AVER(resultReturn != NULL);
+  AVER(FUNCHECK(f));
+  /* Can't check p and s as they are interpreted by the client */
+
+  *resultReturn = (*f)(p, s);
+}