//===-- HostInfoAndroid.cpp -------------------------------------*- C++ -*-===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//

#include "lldb/Host/android/HostInfoAndroid.h"
#include "lldb/Host/linux/HostInfoLinux.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/StringRef.h"

using namespace lldb_private;
using namespace llvm;

void
HostInfoAndroid::ComputeHostArchitectureSupport(ArchSpec &arch_32, ArchSpec &arch_64)
{
    HostInfoLinux::ComputeHostArchitectureSupport(arch_32, arch_64);

    if (arch_32.IsValid())
    {
        arch_32.GetTriple().setEnvironment(llvm::Triple::Android);
    }
    if (arch_64.IsValid())
    {
        arch_64.GetTriple().setEnvironment(llvm::Triple::Android);
    }
}

FileSpec
HostInfoAndroid::GetDefaultShell()
{
    return FileSpec("/system/bin/sh", false);
}

FileSpec
HostInfoAndroid::ResolveLibraryPath(const std::string& module_path, const ArchSpec& arch)
{
    static const char* const ld_library_path_separator = ":";
    static const char* const default_lib32_path[] = {
        "/vendor/lib",
        "/system/lib",
        nullptr
    };
    static const char* const default_lib64_path[] = {
        "/vendor/lib64",
        "/system/lib64",
        nullptr
    };

    if (module_path.empty() || module_path[0] == '/')
        return FileSpec(module_path.c_str(), true);

    SmallVector<StringRef, 4> ld_paths;

    if (const char* ld_library_path = ::getenv("LD_LIBRARY_PATH"))
        StringRef(ld_library_path).split(ld_paths, StringRef(ld_library_path_separator), -1, false);

    const char* const* default_lib_path = nullptr;
    switch (arch.GetAddressByteSize())
    {
        case 4:
            default_lib_path = default_lib32_path;
            break;
        case 8:
            default_lib_path = default_lib64_path;
            break;
        default:
            assert(false && "Unknown address byte size");
            return FileSpec();
    }

    for(const char* const* it = default_lib_path; *it; ++it)
        ld_paths.push_back(StringRef(*it));

    for (const StringRef& path : ld_paths)
    {
        FileSpec file_candidate(path.str().c_str(), true);
        file_candidate.AppendPathComponent(module_path.c_str());

        if (file_candidate.Exists())
            return file_candidate;
    }

    return FileSpec();
}

bool
HostInfoAndroid::ComputeTempFileBaseDirectory(FileSpec &file_spec)
{
    bool success = HostInfoLinux::ComputeTempFileBaseDirectory(file_spec);

    // On Android, there is no path which is guaranteed to be writable. If the user has not
    // provided a path via an environment variable, the generic algorithm will deduce /tmp, which
    // is plain wrong. In that case we have an invalid directory, we substitute the path with
    // /data/local/tmp, which is correct at least in some cases (i.e., when running as shell user).
    if (!success || !file_spec.Exists())
        file_spec = FileSpec("/data/local/tmp", false);

    return file_spec.Exists();
}
