Mojo + NaCl prototype.

mojo/nacl/mojo_syscall_internal.h

Index: mojo/nacl/mojo_syscall_internal.h
diff --git a/mojo/nacl/mojo_syscall_internal.h b/mojo/nacl/mojo_syscall_internal.h
new file mode 100644
index 0000000000000000000000000000000000000000..f0795e63ba72c92dc7ec3629b93c3ca7c72440a0
--- /dev/null
+++ b/mojo/nacl/mojo_syscall_internal.h
@@ -0,0 +1,150 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef MOJO_NACL_MOJO_SYSCALL_INTERNAL_H_
+#define MOJO_NACL_MOJO_SYSCALL_INTERNAL_H_
+
+#include "native_client/src/trusted/service_runtime/nacl_copy.h"
+#include "native_client/src/trusted/service_runtime/sel_ldr.h"
+
+namespace {
+
+class ScopedCopyLock {
+ public:
+  explicit ScopedCopyLock(struct NaClApp* nap) : nap_(nap) {
+    NaClCopyTakeLock(nap_);
+  }
+  ~ScopedCopyLock() {
+    NaClCopyDropLock(nap_);
+  }
+ private:
+  struct NaClApp* nap_;
+};
+
+static inline uintptr_t NaClUserToSysAddrArray(
+    struct NaClApp* nap,
+    uint32_t uaddr,
+    size_t count,
+    size_t size) {
+  // TODO(ncbray): overflow checking
+  size_t range = count * size;
+  return NaClUserToSysAddrRange(nap, uaddr, range);
+}
+
+template <typename T> bool ConvertScalarInput(
+    struct NaClApp* nap,
+    uint32_t user_ptr,
+    T* value) {
+  if (user_ptr) {
+    uintptr_t temp = NaClUserToSysAddrRange(nap, user_ptr, sizeof(T));
+    if (temp != kNaClBadAddress) {
+      *value = *reinterpret_cast<T volatile*>(temp);
+      return true;
+    }
+  }
+  return false;
+}
+
+template <typename T> bool ConvertScalarOutput(
+    struct NaClApp* nap,
+    uint32_t user_ptr,
+    T volatile** sys_ptr) {
+  if (user_ptr) {
+    uintptr_t temp = NaClUserToSysAddrRange(nap, user_ptr, sizeof(T));
+    if (temp != kNaClBadAddress) {
+      *sys_ptr = reinterpret_cast<T volatile*>(temp);
+      return true;
+    }
+  }
+  *sys_ptr = 0; // Paranoia.
+  return false;
+}
+
+template <typename T> bool ConvertScalarInOut(
+    struct NaClApp* nap,
+    uint32_t user_ptr,
+    bool optional,
+    T* value,
+    T volatile** sys_ptr) {
+  if (user_ptr) {
+    uintptr_t temp = NaClUserToSysAddrRange(nap, user_ptr, sizeof(T));
+    if (temp != kNaClBadAddress) {
+      T volatile* converted = reinterpret_cast<T volatile*>(temp);
+      *sys_ptr = converted;
+      *value = *converted;
+      return true;
+    }
+  } else if (optional) {
+    *sys_ptr = 0;
+    *value = static_cast<T>(0); // Paranoia.
+    return true;
+  }
+  *sys_ptr = 0; // Paranoia.
+  *value = static_cast<T>(0); // Paranoia.
+  return false;
+}
+
+template <typename T> bool ConvertArray(
+    struct NaClApp* nap,
+    uint32_t user_ptr,
+    uint32_t length,
+    size_t element_size,
+    bool optional,
+    T** sys_ptr) {
+  if (user_ptr) {
+    uintptr_t temp = NaClUserToSysAddrArray(nap, user_ptr, length,
+                                            element_size);
+    if (temp != kNaClBadAddress) {
+      *sys_ptr = reinterpret_cast<T*>(temp);
+      return true;
+    }
+  } else if (optional) {
+    *sys_ptr = 0;
+    return true;
+  }
+  return false;
+}
+
+template <typename T> bool ConvertBytes(
+    struct NaClApp* nap,
+    uint32_t user_ptr,
+    uint32_t length,
+    bool optional,
+    T** sys_ptr) {
+  if (user_ptr) {
+    uintptr_t temp = NaClUserToSysAddrRange(nap, user_ptr, length);
+    if (temp != kNaClBadAddress) {
+      *sys_ptr = reinterpret_cast<T*>(temp);
+      return true;
+    }
+  } else if (optional) {
+    *sys_ptr = 0;
+    return true;
+  }
+  return false;
+}
+
+// TODO(ncbray): size validation and complete copy.
+// TODO(ncbray): ensure non-null / missized structs are covered by a test case.
+template <typename T> bool ConvertStruct(
+    struct NaClApp* nap,
+    uint32_t user_ptr,
+    bool optional,
+    T** sys_ptr) {
+  if (user_ptr) {
+    uintptr_t temp = NaClUserToSysAddrRange(nap, user_ptr, sizeof(T));
+    if (temp != kNaClBadAddress) {
+      *sys_ptr = reinterpret_cast<T*>(temp);
+      return true;
+    }
+  } else if (optional) {
+    *sys_ptr = 0;
+    return true;
+  }
+  return false;
+}
+
+} // namespace
+
+#endif // MOJO_NACL_MOJO_SYSCALL_INTERNAL_H_