/*
 * COPYRIGHT:       See COPYING in the top level directory
 * PROJECT:         ReactOS kernel
 * FILE:            dll/ntdll/ldr/startup.c
 * PURPOSE:         Process startup for PE executables
 * PROGRAMMERS:     Jean Michault
 *                  Rex Jolliff (rex@lvcablemodem.com)
 */

/* INCLUDES *****************************************************************/

#include <ntdll.h>
#define NDEBUG
#include <debug.h>
#include <win32k/callback.h>

VOID RtlInitializeHeapManager(VOID);
VOID LdrpInitLoader(VOID);
VOID NTAPI RtlpInitDeferedCriticalSection(VOID);
NTSTATUS LdrpAttachThread(VOID);
VOID RtlpInitializeVectoredExceptionHandling(VOID);
extern PTEB LdrpTopLevelDllBeingLoadedTeb;

/* GLOBALS *******************************************************************/

PLDR_DATA_TABLE_ENTRY ExeModule;
static RTL_CRITICAL_SECTION PebLock;
static RTL_CRITICAL_SECTION LoaderLock;
static RTL_BITMAP TlsBitMap;
static RTL_BITMAP TlsExpansionBitMap;
static volatile BOOLEAN LdrpInitialized = FALSE;
static LONG LdrpInitLock = 0;

#define VALUE_BUFFER_SIZE 256

/* FUNCTIONS *****************************************************************/

BOOLEAN
FASTCALL
ReadCompatibilitySetting(HANDLE Key,
                         LPWSTR Value,
                         PKEY_VALUE_PARTIAL_INFORMATION ValueInfo,
                         DWORD * Buffer)
{
    UNICODE_STRING ValueName;
    NTSTATUS Status;
    ULONG Length;

    RtlInitUnicodeString(&ValueName, Value);
    Status = NtQueryValueKey(Key,
                             &ValueName,
                             KeyValuePartialInformation,
                             ValueInfo,
                             VALUE_BUFFER_SIZE,
                             &Length);

    if (!NT_SUCCESS(Status) || (ValueInfo->Type != REG_DWORD))
    {
        RtlFreeUnicodeString(&ValueName);
        return FALSE;
    }

    RtlCopyMemory(Buffer, &ValueInfo->Data[0], sizeof(DWORD));
    RtlFreeUnicodeString(&ValueName);
    return TRUE;
}

VOID
FASTCALL
LoadImageFileExecutionOptions(PPEB Peb)
{
    NTSTATUS Status = STATUS_SUCCESS;
    ULONG Value = 0;
    UNICODE_STRING ValueString;
    UNICODE_STRING ImageName;
    UNICODE_STRING ImagePathName;
    WCHAR ValueBuffer[64];
    ULONG ValueSize;

    if (Peb->ProcessParameters &&
        Peb->ProcessParameters->ImagePathName.Length > 0)
    {
        DPRINT("%wZ\n", &Peb->ProcessParameters->ImagePathName);

        ImagePathName = Peb->ProcessParameters->ImagePathName;
        ImageName.Buffer = ImagePathName.Buffer + ImagePathName.Length / sizeof(WCHAR);
        ImageName.Length = 0;

        while (ImagePathName.Buffer < ImageName.Buffer)
        {
            ImageName.Buffer--;
            if (*ImageName.Buffer == L'\\')
            {
                ImageName.Buffer++;
                break;
            }
        }

        ImageName.Length = ImagePathName.Length -
            (ImageName.Buffer - ImagePathName.Buffer) * sizeof(WCHAR);
        ImageName.MaximumLength = ImageName.Length +
            ImagePathName.MaximumLength - ImagePathName.Length;

        DPRINT("%wZ\n", &ImageName);

        /* global flag */
        Status = LdrQueryImageFileExecutionOptions(&ImageName,
                                                   L"GlobalFlag",
                                                   REG_SZ,
                                                   (PVOID)ValueBuffer,
                                                   sizeof(ValueBuffer),
                                                   &ValueSize);
        if (NT_SUCCESS(Status))
        {
            ValueString.Buffer = ValueBuffer;
            ValueString.Length = ValueSize - sizeof(WCHAR);
            ValueString.MaximumLength = sizeof(ValueBuffer);
            Status = RtlUnicodeStringToInteger(&ValueString, 16, &Value);
            if (NT_SUCCESS(Status))
            {
                Peb->NtGlobalFlag |= Value;
                DPRINT("GlobalFlag: Key='%S', Value=0x%lx\n", ValueBuffer, Value);
            }
        }
        /*
         *  FIXME:
         *   read more options
         */
    }
}

BOOLEAN
FASTCALL
LoadCompatibilitySettings(PPEB Peb)
{
    NTSTATUS Status;
    HANDLE UserKey = NULL;
    HANDLE KeyHandle;
    HANDLE SubKeyHandle;
    OBJECT_ATTRIBUTES ObjectAttributes;
    UNICODE_STRING KeyName = RTL_CONSTANT_STRING(
        L"Software\\Microsoft\\Windows NT\\CurrentVersion\\AppCompatFlags\\Layers");
    UNICODE_STRING ValueName;
    UCHAR ValueBuffer[VALUE_BUFFER_SIZE];
    PKEY_VALUE_PARTIAL_INFORMATION ValueInfo;
    ULONG Length;
    DWORD MajorVersion, MinorVersion, BuildNumber, PlatformId,
          SPMajorVersion, SPMinorVersion = 0;

    if (Peb->ProcessParameters &&
        (Peb->ProcessParameters->ImagePathName.Length > 0))
    {
        Status = RtlOpenCurrentUser(KEY_READ, &UserKey);
        if (!NT_SUCCESS(Status))
        {
            return FALSE;
        }

        InitializeObjectAttributes(&ObjectAttributes,
                                   &KeyName,
                                   OBJ_CASE_INSENSITIVE,
                                   UserKey,
                                   NULL);

        Status = NtOpenKey(&KeyHandle, KEY_QUERY_VALUE, &ObjectAttributes);

        if (!NT_SUCCESS(Status))
        {
            if (UserKey)
                NtClose(UserKey);
            return FALSE;
        }

        /* query version name for application */
        ValueInfo = (PKEY_VALUE_PARTIAL_INFORMATION) ValueBuffer;
        Status = NtQueryValueKey(KeyHandle,
                                 &Peb->ProcessParameters->ImagePathName,
                                 KeyValuePartialInformation,
                                 ValueBuffer,
                                 VALUE_BUFFER_SIZE,
                                 &Length);

        if (!NT_SUCCESS(Status) || (ValueInfo->Type != REG_SZ))
        {
            NtClose(KeyHandle);
            if (UserKey)
                NtClose(UserKey);
            return FALSE;
        }

        ValueName.Length = ValueInfo->DataLength;
        ValueName.MaximumLength = ValueInfo->DataLength;
        ValueName.Buffer = (PWSTR) ValueInfo->Data;

        /* load version info */
        InitializeObjectAttributes(&ObjectAttributes,
                                   &ValueName,
                                   OBJ_CASE_INSENSITIVE,
                                   KeyHandle,
                                   NULL);

        Status = NtOpenKey(&SubKeyHandle, KEY_QUERY_VALUE, &ObjectAttributes);

        if (!NT_SUCCESS(Status))
        {
            NtClose(KeyHandle);
            if (UserKey)
                NtClose(UserKey);
            return FALSE;
        }

        DPRINT("Loading version information for: %wZ\n", &ValueName);

        /* read settings from registry */
        if (!ReadCompatibilitySetting(SubKeyHandle, L"MajorVersion", ValueInfo, &MajorVersion))
            goto finish;
        if (!ReadCompatibilitySetting(SubKeyHandle, L"MinorVersion", ValueInfo, &MinorVersion))
            goto finish;
        if (!ReadCompatibilitySetting(SubKeyHandle, L"BuildNumber", ValueInfo, &BuildNumber))
            goto finish;
        if (!ReadCompatibilitySetting(SubKeyHandle, L"PlatformId", ValueInfo, &PlatformId))
            goto finish;

        /* now assign the settings */
        Peb->OSMajorVersion =  (ULONG) MajorVersion;
        Peb->OSMinorVersion =  (ULONG) MinorVersion;
        Peb->OSBuildNumber  = (USHORT) BuildNumber;
        Peb->OSPlatformId   =  (ULONG) PlatformId;

        /* optional service pack version numbers */
        if (ReadCompatibilitySetting(SubKeyHandle,
                                     L"SPMajorVersion",
                                     ValueInfo,
                                     &SPMajorVersion) &&
            ReadCompatibilitySetting(SubKeyHandle,
                                     L"SPMinorVersion",
                                     ValueInfo,
                                     &SPMinorVersion))
        {
            Peb->OSCSDVersion = ((SPMajorVersion & 0xFF) << 8) |
                                (SPMinorVersion & 0xFF);
        }

finish:
        /* we're finished */
        NtClose(SubKeyHandle);
        NtClose(KeyHandle);
        if (UserKey)
            NtClose(UserKey);
        return TRUE;
    }

    return FALSE;
}

static
VOID
LdrpInit2(PCONTEXT Context,
          PVOID SystemArgument1,
          PVOID SystemArgument2)
{
    PIMAGE_NT_HEADERS NTHeaders;
    PEPFUNC EntryPoint;
    PIMAGE_DOS_HEADER PEDosHeader;
    PVOID ImageBase;
    PPEB Peb = NtCurrentPeb();
    PLDR_DATA_TABLE_ENTRY NtModule;     // ntdll
    NLSTABLEINFO NlsTable;
    WCHAR FullNtDllPath[MAX_PATH];
    SYSTEM_BASIC_INFORMATION SystemInformation;
    NTSTATUS Status;
    PVOID BaseAddress = SystemArgument1;

    DPRINT("LdrpInit()\n");
    DPRINT("Peb %p\n", Peb);
    ImageBase = Peb->ImageBaseAddress;
    DPRINT("ImageBase %p\n", ImageBase);

    if (ImageBase <= (PVOID) 0x1000)
    {
        DPRINT("ImageBase is null\n");
        ZwTerminateProcess(NtCurrentProcess(), STATUS_INVALID_IMAGE_FORMAT);
    }

    /*  If MZ header exists  */
    PEDosHeader = (PIMAGE_DOS_HEADER) ImageBase;
    DPRINT("PEDosHeader %p\n", PEDosHeader);

    if (PEDosHeader->e_magic != IMAGE_DOS_SIGNATURE ||
        PEDosHeader->e_lfanew == 0L ||
        *(PULONG)((PUCHAR)ImageBase + PEDosHeader->e_lfanew) != IMAGE_NT_SIGNATURE)
    {
        DPRINT1("Image has bad header\n");
        ZwTerminateProcess(NtCurrentProcess(), STATUS_INVALID_IMAGE_FORMAT);
    }

    /* normalize process parameters */
    RtlNormalizeProcessParams(Peb->ProcessParameters);

    /* Initialize NLS data */
    RtlInitNlsTables(Peb->AnsiCodePageData,
                     Peb->OemCodePageData,
                     Peb->UnicodeCaseTableData,
                     &NlsTable);
    RtlResetRtlTranslations(&NlsTable);

    NTHeaders = (PIMAGE_NT_HEADERS)((ULONG_PTR)ImageBase + PEDosHeader->e_lfanew);

    /* Get number of processors */
    DPRINT("Here\n");
    Status = ZwQuerySystemInformation(SystemBasicInformation,
                                      &SystemInformation,
                                      sizeof(SYSTEM_BASIC_INFORMATION),
                                      NULL);
    DPRINT("Here2\n");
    if (!NT_SUCCESS(Status))
    {
        ZwTerminateProcess(NtCurrentProcess(), Status);
    }

    Peb->NumberOfProcessors = SystemInformation.NumberOfProcessors;

    /* Initialize Critical Section Data */
    RtlpInitDeferedCriticalSection();

    /* create process heap */
    RtlInitializeHeapManager();
    Peb->ProcessHeap = RtlCreateHeap(HEAP_GROWABLE,
                                     NULL,
                                     NTHeaders->OptionalHeader.SizeOfHeapReserve,
                                     NTHeaders->OptionalHeader.SizeOfHeapCommit,
                                     NULL,
                                     NULL);
    if (Peb->ProcessHeap == 0)
    {
        DPRINT1("Failed to create process heap\n");
        ZwTerminateProcess(NtCurrentProcess(), STATUS_INSUFFICIENT_RESOURCES);
    }

    /* initialized vectored exception handling */
    RtlpInitializeVectoredExceptionHandling();

    /* initalize peb lock support */
    RtlInitializeCriticalSection(&PebLock);
    Peb->FastPebLock = &PebLock;

    /* initialize tls bitmaps */
    RtlInitializeBitMap(&TlsBitMap, Peb->TlsBitmapBits, TLS_MINIMUM_AVAILABLE);
    RtlInitializeBitMap(&TlsExpansionBitMap, Peb->TlsExpansionBitmapBits, TLS_EXPANSION_SLOTS);

    Peb->TlsBitmap = &TlsBitMap;
    Peb->TlsExpansionBitmap = &TlsExpansionBitMap;
    Peb->TlsExpansionCounter = TLS_MINIMUM_AVAILABLE;

    /* Initialize table of callbacks for the kernel. */
    Peb->KernelCallbackTable = RtlAllocateHeap(RtlGetProcessHeap(),
                                               0,
                                               sizeof(PVOID) *
                                                (USER32_CALLBACK_MAXIMUM + 1));
    if (Peb->KernelCallbackTable == NULL)
    {
        DPRINT1("Failed to create callback table\n");
        ZwTerminateProcess(NtCurrentProcess(), STATUS_INSUFFICIENT_RESOURCES);
    }

    /* initalize loader lock */
    RtlInitializeCriticalSection(&LoaderLock);
    Peb->LoaderLock = &LoaderLock;

    /* create loader information */
    Peb->Ldr = (PPEB_LDR_DATA) RtlAllocateHeap(Peb->ProcessHeap,
                                               0,
                                               sizeof(PEB_LDR_DATA));
    if (Peb->Ldr == NULL)
    {
        DPRINT1("Failed to create loader data\n");
        ZwTerminateProcess(NtCurrentProcess(), STATUS_INSUFFICIENT_RESOURCES);
    }

    Peb->Ldr->Length = sizeof(PEB_LDR_DATA);
    Peb->Ldr->Initialized = FALSE;
    Peb->Ldr->SsHandle = NULL;
    InitializeListHead(&Peb->Ldr->InLoadOrderModuleList);
    InitializeListHead(&Peb->Ldr->InMemoryOrderModuleList);
    InitializeListHead(&Peb->Ldr->InInitializationOrderModuleList);

    /* Load compatibility settings */
    LoadCompatibilitySettings(Peb);

    /* Load execution options */
    LoadImageFileExecutionOptions(Peb);

    /* build full ntdll path */
    wcscpy(FullNtDllPath, SharedUserData->NtSystemRoot);
    wcscat(FullNtDllPath, L"\\system32\\ntdll.dll");

    /* add entry for ntdll */
    NtModule = (PLDR_DATA_TABLE_ENTRY)
                RtlAllocateHeap(Peb->ProcessHeap,
                                0,
                                sizeof(LDR_DATA_TABLE_ENTRY));
    if (NtModule == NULL)
    {
        DPRINT1("Failed to create loader module entry (NTDLL)\n");
        ZwTerminateProcess(NtCurrentProcess(), STATUS_INSUFFICIENT_RESOURCES);
    }
    memset(NtModule, 0, sizeof(LDR_DATA_TABLE_ENTRY));

    NtModule->DllBase = BaseAddress;
    NtModule->EntryPoint = 0;       /* no entry point */
    RtlCreateUnicodeString(&NtModule->FullDllName, FullNtDllPath);
    RtlCreateUnicodeString(&NtModule->BaseDllName, L"ntdll.dll");
    NtModule->Flags = LDRP_IMAGE_DLL | LDRP_ENTRY_PROCESSED;

    NtModule->LoadCount = -1;       /* don't unload */
    NtModule->TlsIndex = -1;
    NtModule->SectionPointer = NULL;
    NtModule->CheckSum = 0;

    NTHeaders = RtlImageNtHeader(NtModule->DllBase);
    NtModule->SizeOfImage = LdrpGetResidentSize(NTHeaders);
    NtModule->TimeDateStamp = NTHeaders->FileHeader.TimeDateStamp;

    InsertTailList(&Peb->Ldr->InLoadOrderModuleList,
                   &NtModule->InLoadOrderLinks);
    InsertTailList(&Peb->Ldr->InInitializationOrderModuleList,
                   &NtModule->InInitializationOrderModuleList);

    /* add entry for executable (becomes first list entry) */
    ExeModule = (PLDR_DATA_TABLE_ENTRY)
                 RtlAllocateHeap(Peb->ProcessHeap,
                                 0,
                                 sizeof(LDR_DATA_TABLE_ENTRY));
    if (ExeModule == NULL)
    {
        DPRINT1("Failed to create loader module infomation\n");
        ZwTerminateProcess(NtCurrentProcess(), STATUS_INSUFFICIENT_RESOURCES);
    }

    ExeModule->DllBase = Peb->ImageBaseAddress;

    if ((Peb->ProcessParameters == NULL) ||
        (Peb->ProcessParameters->ImagePathName.Length == 0))
    {
        DPRINT1("Failed to access the process parameter block\n");
        ZwTerminateProcess(NtCurrentProcess(), STATUS_UNSUCCESSFUL);
    }

    RtlCreateUnicodeString(&ExeModule->FullDllName,
                           Peb->ProcessParameters->ImagePathName.Buffer);
    RtlCreateUnicodeString(&ExeModule->BaseDllName,
                           wcsrchr(ExeModule->FullDllName.Buffer, L'\\') + 1);

    DPRINT("BaseDllName '%wZ'  FullDllName '%wZ'\n", &ExeModule->BaseDllName, &ExeModule->FullDllName);

    ExeModule->Flags = LDRP_ENTRY_PROCESSED;
    ExeModule->LoadCount = -1;      /* don't unload */
    ExeModule->TlsIndex = -1;
    ExeModule->SectionPointer = NULL;
    ExeModule->CheckSum = 0;

    NTHeaders = RtlImageNtHeader(ExeModule->DllBase);
    ExeModule->SizeOfImage = LdrpGetResidentSize(NTHeaders);
    ExeModule->TimeDateStamp = NTHeaders->FileHeader.TimeDateStamp;

    LdrpTopLevelDllBeingLoadedTeb = NtCurrentTeb();

    InsertHeadList(&Peb->Ldr->InLoadOrderModuleList,
                   &ExeModule->InLoadOrderLinks);

    LdrpInitLoader();

    EntryPoint = LdrPEStartup((PVOID)ImageBase, NULL, NULL, NULL);
    ExeModule->EntryPoint = EntryPoint;

    /* all required dlls are loaded now */
    Peb->Ldr->Initialized = TRUE;

    /* Check before returning that we can run the image safely. */
    if (EntryPoint == NULL)
    {
        DPRINT1("Failed to initialize image\n");
        ZwTerminateProcess(NtCurrentProcess(), STATUS_INVALID_IMAGE_FORMAT);
    }

    /* Break into debugger */
    if (Peb->BeingDebugged)
        DbgBreakPoint();
}

VOID
NTAPI
LdrpInit(PCONTEXT Context,
         PVOID SystemArgument1,
         PVOID SystemArgument2)
{
    if (!LdrpInitialized)
    {
        if (!_InterlockedExchange(&LdrpInitLock, 1))
        {
            LdrpInit2(Context, SystemArgument1, SystemArgument2);
            LdrpInitialized = TRUE;
        }
        else
        {
            LARGE_INTEGER Interval = {{-200000, -1}};

            do
            {
                NtDelayExecution(FALSE, &Interval);
            }
            while (!LdrpInitialized);
        }
    }

    /* attach the thread */
    RtlEnterCriticalSection(NtCurrentPeb()->LoaderLock);
    LdrpAttachThread();
    RtlLeaveCriticalSection(NtCurrentPeb()->LoaderLock);
}

/* EOF */