2019-08-14 10:47:11 +02:00
|
|
|
//===-- sanitizer_local_address_space_view.h --------------------*- C++ -*-===//
|
|
|
|
//
|
|
|
|
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
|
|
|
|
// See https://llvm.org/LICENSE.txt for license information.
|
|
|
|
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
|
|
|
|
//
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
//
|
|
|
|
// `LocalAddressSpaceView` provides the local (i.e. target and current address
|
2021-05-12 14:37:22 +02:00
|
|
|
// space are the same) implementation of the `AddressSpaceView` interface which
|
2019-08-14 10:47:11 +02:00
|
|
|
// provides a simple interface to load memory from another process (i.e.
|
|
|
|
// out-of-process)
|
|
|
|
//
|
|
|
|
// The `AddressSpaceView` interface requires that the type can be used as a
|
|
|
|
// template parameter to objects that wish to be able to operate in an
|
|
|
|
// out-of-process manner. In normal usage, objects are in-process and are thus
|
|
|
|
// instantiated with the `LocalAddressSpaceView` type. This type is used to
|
|
|
|
// load any pointers in instance methods. This implementation is effectively
|
|
|
|
// a no-op. When an object is to be used in an out-of-process manner it is
|
2021-09-27 19:43:33 +02:00
|
|
|
// instantiated with the `RemoteAddressSpaceView` type.
|
2019-08-14 10:47:11 +02:00
|
|
|
//
|
|
|
|
// By making `AddressSpaceView` a template parameter of an object, it can
|
|
|
|
// change its implementation at compile time which has no run time overhead.
|
|
|
|
// This also allows unifying in-process and out-of-process code which avoids
|
|
|
|
// code duplication.
|
|
|
|
//
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#ifndef SANITIZER_LOCAL_ADDRES_SPACE_VIEW_H
|
|
|
|
#define SANITIZER_LOCAL_ADDRES_SPACE_VIEW_H
|
|
|
|
|
|
|
|
namespace __sanitizer {
|
|
|
|
struct LocalAddressSpaceView {
|
|
|
|
// Load memory `sizeof(T) * num_elements` bytes of memory from the target
|
|
|
|
// process (always local for this implementation) starting at address
|
|
|
|
// `target_address`. The local copy of this memory is returned as a pointer.
|
|
|
|
// The caller should not write to this memory. The behaviour when doing so is
|
|
|
|
// undefined. Callers should use `LoadWritable()` to get access to memory
|
|
|
|
// that is writable.
|
|
|
|
//
|
|
|
|
// The lifetime of loaded memory is implementation defined.
|
|
|
|
template <typename T>
|
|
|
|
static const T *Load(const T *target_address, uptr num_elements = 1) {
|
|
|
|
// The target address space is the local address space so
|
|
|
|
// nothing needs to be copied. Just return the pointer.
|
|
|
|
return target_address;
|
|
|
|
}
|
|
|
|
|
|
|
|
// Load memory `sizeof(T) * num_elements` bytes of memory from the target
|
|
|
|
// process (always local for this implementation) starting at address
|
|
|
|
// `target_address`. The local copy of this memory is returned as a pointer.
|
|
|
|
// The memory returned may be written to.
|
|
|
|
//
|
|
|
|
// Writes made to the returned memory will be visible in the memory returned
|
|
|
|
// by subsequent `Load()` or `LoadWritable()` calls provided the
|
|
|
|
// `target_address` parameter is the same. It is not guaranteed that the
|
|
|
|
// memory returned by previous calls to `Load()` will contain any performed
|
|
|
|
// writes. If two or more overlapping regions of memory are loaded via
|
|
|
|
// separate calls to `LoadWritable()`, it is implementation defined whether
|
|
|
|
// writes made to the region returned by one call are visible in the regions
|
|
|
|
// returned by other calls.
|
|
|
|
//
|
|
|
|
// Given the above it is recommended to load the largest possible object
|
|
|
|
// that requires modification (e.g. a class) rather than individual fields
|
|
|
|
// from a class to avoid issues with overlapping writable regions.
|
|
|
|
//
|
|
|
|
// The lifetime of loaded memory is implementation defined.
|
|
|
|
template <typename T>
|
|
|
|
static T *LoadWritable(T *target_address, uptr num_elements = 1) {
|
|
|
|
// The target address space is the local address space so
|
|
|
|
// nothing needs to be copied. Just return the pointer.
|
|
|
|
return target_address;
|
|
|
|
}
|
|
|
|
};
|
|
|
|
} // namespace __sanitizer
|
|
|
|
|
|
|
|
#endif
|