// Copyright 2016 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#pragma once

#include <elf.h>
#include <fbl/array.h>
#include <fbl/function.h>
#include <fbl/string_piece.h>
#include <lib/zx/process.h>
#include <stdint.h>

// TODO(jakehehrlich): Replace ArrayRef here with something more like std::span
// in fbl.
template <class T>
class ArrayRef {
public:
    ArrayRef() = default;
    template <size_t N>
    ArrayRef(const T (&arr)[N])
        : ptr_(arr), sz_(N) {}
    ArrayRef(const fbl::Array<T>& arr)
        : ptr_(arr.get()), sz_(arr.size()) {}
    ArrayRef(const T* ptr, size_t sz)
        : ptr_(ptr), sz_(sz) {}

    bool empty() const {
        return sz_ == 0;
    }

    const T* get() const {
        return ptr_;
    }

    const T* begin() const {
        return ptr_;
    }

    const T* end() const {
        return ptr_ + sz_;
    }

    size_t size() const {
        return sz_;
    }

    const T& operator[](size_t idx) const {
        return ptr_[idx];
    }

private:
    const T* ptr_ = nullptr;
    size_t sz_ = 0;
};

template <class T>
bool operator==(ArrayRef<T> a, ArrayRef<T> b) {
    if (a.size() != b.size()) {
        return false;
    }
    for (size_t i = 0; i < a.size(); ++i) {
        if (a[i] != b[i]) {
            return false;
        }
    }
    return true;
}

template <typename T>
ArrayRef<T> MakeArrayRef(const T* p, size_t sz) {
    return {p, sz};
}

template <typename T, size_t N>
ArrayRef<T> MakeArrayRef(const T (&arr)[N]) {
    return {arr};
}

struct ModuleInfo {
    fbl::StringPiece name;
    uintptr_t vaddr;
    ArrayRef<uint8_t> build_id;
    const Elf64_Ehdr& ehdr;
    ArrayRef<Elf64_Phdr> phdrs;
};

#if defined(__aarch64__)
constexpr Elf64_Half kNativeElfMachine = EM_AARCH64;
#elif defined(__x86_64__)
constexpr Elf64_Half kNativeElfMachine = EM_X86_64;
#endif

using ModuleAction = fbl::Function<void(const ModuleInfo&)>;
extern zx_status_t ForEachModule(const zx::process&, ModuleAction);