mprotect system call exposed to the untrusted code.

src/untrusted/irt/irt.h

Index: src/untrusted/irt/irt.h
diff --git a/src/untrusted/irt/irt.h b/src/untrusted/irt/irt.h
index d417be8fe41ad4f9427beed790f6564a9f19bab8..668f3add1428441662309062167e4eac603d8521 100644
--- a/src/untrusted/irt/irt.h
+++ b/src/untrusted/irt/irt.h
@@ -87,10 +87,12 @@ struct nacl_irt_filename {
 };
 
 #define NACL_IRT_MEMORY_v0_1    "nacl-irt-memory-0.1"
+#define NACL_IRT_MEMORY_v0_2    "nacl-irt-memory-0.2"
 struct nacl_irt_memory {
   int (*sysbrk)(void **newbrk);
   int (*mmap)(void **addr, size_t len, int prot, int flags, int fd, off_t off);
   int (*munmap)(void *addr, size_t len);
+  int (*mprotect)(void *addr, size_t len, int prot);

[Mark Seaborn, 2012/10/18 00:27:23]

Modifying struct nacl_irt_memory in-place means we've lost the information that
v0_1 didn't include mprotect().  I don't like that.  I think we should retain
that information in the headers as documentation in some way.

[bsy, 2012/10/18 19:46:09]

the pattern should be something like:

struct nacl_irt_memory {
  int (*sysbrk)(...);
  int (*mmap)(...);
  int (*munmap)(...);
};

struct nacl_irt_memory_v0_2 {
  struct nacl_irt_memory base;
  int (*mprotect)(...);
};

so information that the new version of the interface is a strict extension of
the older one is obvious.  if we were willing to use --fms-extensions or
-fplan9-extensions, "base" could be elided.

 };
 
 #define NACL_IRT_DYNCODE_v0_1   "nacl-irt-dyncode-0.1"