/*

 * Windows support routines for PhysicsFS.

 *

 * Please see the file LICENSE.txt in the source's root directory.

 *

 *  This file written by Ryan C. Gordon, and made sane by Gregory S. Read.

 */

#define __PHYSICSFS_INTERNAL__

#include "physfs_platforms.h"

#ifdef PHYSFS_PLATFORM_WINDOWS

/* Forcibly disable UNICODE macro, since we manage this ourselves. */

#ifdef UNICODE

#undef UNICODE

#endif

#define WIN32_LEAN_AND_MEAN 1

#include <windows.h>

#include <userenv.h>

#include <shlobj.h>

#include <dbt.h>

#include <errno.h>

#include <ctype.h>

#include <time.h>

#include "physfs_internal.h"

#define LOWORDER_UINT64(pos) ((PHYSFS_uint32) (pos & 0xFFFFFFFF))

#define HIGHORDER_UINT64(pos) ((PHYSFS_uint32) ((pos >> 32) & 0xFFFFFFFF))

/*

 * Users without the platform SDK don't have this defined.  The original docs

 *  for SetFilePointer() just said to compare with 0xFFFFFFFF, so this should

 *  work as desired.

 */

#define PHYSFS_INVALID_SET_FILE_POINTER  0xFFFFFFFF

/* just in case... */

#define PHYSFS_INVALID_FILE_ATTRIBUTES   0xFFFFFFFF

/* Not defined before the Vista SDK. */

#define PHYSFS_IO_REPARSE_TAG_SYMLINK    0xA000000C

#define UTF8_TO_UNICODE_STACK_MACRO(w_assignto, str) { \

    if (str == NULL) \

        w_assignto = NULL; \

    else { \

        const PHYSFS_uint64 len = (PHYSFS_uint64) ((strlen(str) + 1) * 2); \

        w_assignto = (WCHAR *) __PHYSFS_smallAlloc(len); \

        if (w_assignto != NULL) \

            PHYSFS_utf8ToUtf16(str, (PHYSFS_uint16 *) w_assignto, len); \

    } \

} \

/* Note this counts WCHARs, not codepoints! */

static PHYSFS_uint64 wStrLen(const WCHAR *wstr)

{

    PHYSFS_uint64 len = 0;

    while (*(wstr++))

        len++;

    return len;

} /* wStrLen */

static char *unicodeToUtf8Heap(const WCHAR *w_str)

{

    char *retval = NULL;

    if (w_str != NULL)

    {

        void *ptr = NULL;

        const PHYSFS_uint64 len = (wStrLen(w_str) * 4) + 1;

        retval = allocator.Malloc(len);

        BAIL_IF_MACRO(!retval, PHYSFS_ERR_OUT_OF_MEMORY, NULL);

        PHYSFS_utf8FromUtf16((const PHYSFS_uint16 *) w_str, retval, len);

        ptr = allocator.Realloc(retval, strlen(retval) + 1); /* shrink. */

        if (ptr != NULL)

            retval = (char *) ptr;

    } /* if */

    return retval;

} /* unicodeToUtf8Heap */

/* !!! FIXME: do we really need readonly? If not, do we need this struct? */

typedef struct

{

    HANDLE handle;

    int readonly;

} WinApiFile;

/* !!! FIXME: we cache userDir in physfs.c during PHYSFS_init(), too. */

static char *userDir = NULL;

static HANDLE libUserEnv = NULL;

static HANDLE detectCDThreadHandle = NULL;

static HWND detectCDHwnd = 0;

static volatile int initialDiscDetectionComplete = 0;

static volatile DWORD drivesWithMediaBitmap = 0;

static PHYSFS_ErrorCode errcodeFromWinApiError(const DWORD err)

{

    /*

     * win32 error codes are sort of a tricky thing; Microsoft intentionally

     *  doesn't list which ones a given API might trigger, there are several

     *  with overlapping and unclear meanings...and there's 16 thousand of

     *  them in Windows 7. It looks like the ones we care about are in the

     *  first 500, but I can't say this list is perfect; we might miss

     *  important values or misinterpret others.

     *

     * Don't treat this list as anything other than a work in progress.

     */

    switch (err)

    {

        case ERROR_SUCCESS: return PHYSFS_ERR_OK;

        case ERROR_ACCESS_DENIED: return PHYSFS_ERR_PERMISSION;

        case ERROR_NETWORK_ACCESS_DENIED: return PHYSFS_ERR_PERMISSION;

        case ERROR_NOT_READY: return PHYSFS_ERR_IO;

        case ERROR_CRC: return PHYSFS_ERR_IO;

        case ERROR_SEEK: return PHYSFS_ERR_IO;

        case ERROR_SECTOR_NOT_FOUND: return PHYSFS_ERR_IO;

        case ERROR_NOT_DOS_DISK: return PHYSFS_ERR_IO;

        case ERROR_WRITE_FAULT: return PHYSFS_ERR_IO;

        case ERROR_READ_FAULT: return PHYSFS_ERR_IO;

        case ERROR_DEV_NOT_EXIST: return PHYSFS_ERR_IO;

        /* !!! FIXME: ?? case ELOOP: return PHYSFS_ERR_SYMLINK_LOOP; */

        case ERROR_BUFFER_OVERFLOW: return PHYSFS_ERR_BAD_FILENAME;

        case ERROR_INVALID_NAME: return PHYSFS_ERR_BAD_FILENAME;

        case ERROR_BAD_PATHNAME: return PHYSFS_ERR_BAD_FILENAME;

        case ERROR_DIRECTORY: return PHYSFS_ERR_BAD_FILENAME;

        case ERROR_FILE_NOT_FOUND: return PHYSFS_ERR_NO_SUCH_PATH;

        case ERROR_PATH_NOT_FOUND: return PHYSFS_ERR_NO_SUCH_PATH;

        case ERROR_DELETE_PENDING: return PHYSFS_ERR_NO_SUCH_PATH;

        case ERROR_INVALID_DRIVE: return PHYSFS_ERR_NO_SUCH_PATH;

        case ERROR_HANDLE_DISK_FULL: return PHYSFS_ERR_NO_SPACE;

        case ERROR_DISK_FULL: return PHYSFS_ERR_NO_SPACE;

        /* !!! FIXME: ?? case ENOTDIR: return PHYSFS_ERR_NO_SUCH_PATH; */

        /* !!! FIXME: ?? case EISDIR: return PHYSFS_ERR_NOT_A_FILE; */

        case ERROR_WRITE_PROTECT: return PHYSFS_ERR_READ_ONLY;

        case ERROR_LOCK_VIOLATION: return PHYSFS_ERR_BUSY;

        case ERROR_SHARING_VIOLATION: return PHYSFS_ERR_BUSY;

        case ERROR_CURRENT_DIRECTORY: return PHYSFS_ERR_BUSY;

        case ERROR_DRIVE_LOCKED: return PHYSFS_ERR_BUSY;

        case ERROR_PATH_BUSY: return PHYSFS_ERR_BUSY;

        case ERROR_BUSY: return PHYSFS_ERR_BUSY;

        case ERROR_NOT_ENOUGH_MEMORY: return PHYSFS_ERR_OUT_OF_MEMORY;

        case ERROR_OUTOFMEMORY: return PHYSFS_ERR_OUT_OF_MEMORY;

        case ERROR_DIR_NOT_EMPTY: return PHYSFS_ERR_DIR_NOT_EMPTY;

        default: return PHYSFS_ERR_OS_ERROR;

    } /* switch */

} /* errcodeFromWinApiError */

static inline PHYSFS_ErrorCode errcodeFromWinApi(void)

{

    return errcodeFromWinApiError(GetLastError());

} /* errcodeFromWinApi */

/*

 * On success, module-scope variable (userDir) will have a pointer to

 *  a malloc()'d string of the user's profile dir, and a non-zero value is

 *  returned. If we can't determine the profile dir, (userDir) will

 *  be NULL, and zero is returned.

 */

static int determineUserDir(void)

{

    typedef BOOL (WINAPI *fnGetUserProfDirW)(HANDLE, LPWSTR, LPDWORD);

    fnGetUserProfDirW pGetDir = NULL;

    HANDLE accessToken = NULL;       /* Security handle to process */

    if (userDir != NULL)

        return 1;  /* already good to go. */

    pGetDir = (fnGetUserProfDirW)

        GetProcAddress(libUserEnv, "GetUserProfileDirectoryW");

    BAIL_IF_MACRO(pGetDir == NULL, errcodeFromWinApi(), 0);

    if (!OpenProcessToken(GetCurrentProcess(), TOKEN_QUERY, &accessToken))

        BAIL_MACRO(errcodeFromWinApi(), 0);

    else

    {

        DWORD psize = 0;

        WCHAR dummy = 0;

        LPWSTR wstr = NULL;

        BOOL rc = 0;

        /*

         * Should fail. Will write the size of the profile path in

         *  psize. Also note that the second parameter can't be

         *  NULL or the function fails.

         */

    	rc = pGetDir(accessToken, &dummy, &psize);

        assert(!rc);  /* !!! FIXME: handle this gracefully. */

        (void) rc;

        /* Allocate memory for the profile directory */

        wstr = (LPWSTR) __PHYSFS_smallAlloc(psize * sizeof (WCHAR));

        if (wstr != NULL)

        {

            if (pGetDir(accessToken, wstr, &psize))

                userDir = unicodeToUtf8Heap(wstr);

            __PHYSFS_smallFree(wstr);

        } /* if */

        CloseHandle(accessToken);

    } /* if */

    return 1;  /* We made it: hit the showers. */

} /* determineUserDir */

typedef BOOL (WINAPI *fnSTEM)(DWORD, LPDWORD b);

static DWORD pollDiscDrives(void)

{

    /* Try to use SetThreadErrorMode(), which showed up in Windows 7. */

    HANDLE lib = LoadLibraryA("kernel32.dll");

    fnSTEM stem = NULL;

    char drive[4] = { 'x', ':', '\\', '\0' };

    DWORD oldErrorMode = 0;

    DWORD drives = 0;

    DWORD i;

    if (lib)

        stem = (fnSTEM) GetProcAddress(lib, "SetThreadErrorMode");

    if (stem)

        stem(SEM_FAILCRITICALERRORS, &oldErrorMode);

    else

        oldErrorMode = SetErrorMode(SEM_FAILCRITICALERRORS);

    /* Do detection. This may block if a disc is spinning up. */

    for (i = 'A'; i <= 'Z'; i++)

    {

        DWORD tmp = 0;

        drive[0] = (char) i;

        if (GetDriveTypeA(drive) != DRIVE_CDROM)

            continue;

        /* If this function succeeds, there's media in the drive */

        if (GetVolumeInformationA(drive, NULL, 0, NULL, NULL, &tmp, NULL, 0))

            drives |= (1 << (i - 'A'));

    } /* for */

    if (stem)

        stem(oldErrorMode, NULL);

    else

        SetErrorMode(oldErrorMode);

    if (lib)

        FreeLibrary(lib);

    return drives;

} /* pollDiscDrives */

static LRESULT CALLBACK detectCDWndProc(HWND hwnd, UINT msg,

                                        WPARAM wp, LPARAM lparam)

{

    PDEV_BROADCAST_HDR lpdb = (PDEV_BROADCAST_HDR) lparam;

    PDEV_BROADCAST_VOLUME lpdbv = (PDEV_BROADCAST_VOLUME) lparam;

    const int removed = (wp == DBT_DEVICEREMOVECOMPLETE);

    if (msg == WM_DESTROY)

        return 0;

    else if ((msg != WM_DEVICECHANGE) ||

             ((wp != DBT_DEVICEARRIVAL) && (wp != DBT_DEVICEREMOVECOMPLETE)) ||

             (lpdb->dbch_devicetype != DBT_DEVTYP_VOLUME) ||

             ((lpdbv->dbcv_flags & DBTF_MEDIA) == 0))

    {

        return DefWindowProcW(hwnd, msg, wp, lparam);

    } /* else if */

    if (removed)

        drivesWithMediaBitmap &= ~lpdbv->dbcv_unitmask;

    else

        drivesWithMediaBitmap |= lpdbv->dbcv_unitmask;

    return TRUE;

} /* detectCDWndProc */

static DWORD WINAPI detectCDThread(LPVOID lpParameter)

{

    const char *classname = "PhysicsFSDetectCDCatcher";

    const char *winname = "PhysicsFSDetectCDMsgWindow";

    HINSTANCE hInstance = GetModuleHandleW(NULL);

    ATOM class_atom = 0;

    WNDCLASSEXA wce;

    MSG msg;

    memset(&wce, '\0', sizeof (wce));

    wce.cbSize = sizeof (wce);

    wce.lpfnWndProc = detectCDWndProc;

    wce.lpszClassName = classname;

    wce.hInstance = hInstance;

    class_atom = RegisterClassExA(&wce);

    if (class_atom == 0)

    {

        initialDiscDetectionComplete = 1;  /* let main thread go on. */

        return 0;

    } /* if */

    detectCDHwnd = CreateWindowExA(0, classname, winname, WS_OVERLAPPEDWINDOW,

                        CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT,

                        CW_USEDEFAULT, HWND_DESKTOP, NULL, hInstance, NULL);

    if (detectCDHwnd == NULL)

    {

        initialDiscDetectionComplete = 1;  /* let main thread go on. */

        UnregisterClassA(classname, hInstance);

        return 0;

    } /* if */

    /* We'll get events when discs come and go from now on. */

    /* Do initial detection, possibly blocking awhile... */

    drivesWithMediaBitmap = pollDiscDrives();

    initialDiscDetectionComplete = 1;  /* let main thread go on. */

    do

    {

        const BOOL rc = GetMessageW(&msg, detectCDHwnd, 0, 0);

        if ((rc == 0) || (rc == -1))

            break;  /* don't care if WM_QUIT or error break this loop. */

        TranslateMessage(&msg);

        DispatchMessageW(&msg);

    } while (1);

    /* we've been asked to quit. */

    DestroyWindow(detectCDHwnd);

    do

    {

        const BOOL rc = GetMessage(&msg, detectCDHwnd, 0, 0);

        if ((rc == 0) || (rc == -1))

            break;

        TranslateMessage(&msg);

        DispatchMessageW(&msg);

    } while (1);

    UnregisterClassA(classname, hInstance);

    return 0;

} /* detectCDThread */

void __PHYSFS_platformDetectAvailableCDs(PHYSFS_StringCallback cb, void *data)

{

    char drive_str[4] = { 'x', ':', '\\', '\0' };

    DWORD drives = 0;

    DWORD i;

    /*

     * If you poll a drive while a user is inserting a disc, the OS will

     *  block this thread until the drive has spun up. So we swallow the risk

     *  once for initial detection, and spin a thread that will get device

     *  events thereafter, for apps that use this interface to poll for

     *  disc insertion.

     */

    if (!detectCDThreadHandle)

    {

        initialDiscDetectionComplete = 0;

        detectCDThreadHandle = CreateThread(NULL,0,detectCDThread,NULL,0,NULL);

        if (detectCDThreadHandle == NULL)

            return;  /* oh well. */

        while (!initialDiscDetectionComplete)

            Sleep(50);

    } /* if */

    drives = drivesWithMediaBitmap; /* whatever the thread has seen, we take. */

    for (i = 'A'; i <= 'Z'; i++)

    {

        if (drives & (1 << (i - 'A')))

        {

            drive_str[0] = (char) i;

            cb(data, drive_str);

        } /* if */

    } /* for */

} /* __PHYSFS_platformDetectAvailableCDs */

char *__PHYSFS_platformCalcBaseDir(const char *argv0)

{

    DWORD buflen = 64;

    LPWSTR modpath = NULL;

    char *retval = NULL;

    while (1)

    {

        DWORD rc;

        void *ptr;

        if ( (ptr = allocator.Realloc(modpath, buflen*sizeof(WCHAR))) == NULL )

        {

            allocator.Free(modpath);

            BAIL_MACRO(PHYSFS_ERR_OUT_OF_MEMORY, NULL);

        } /* if */

        modpath = (LPWSTR) ptr;

        rc = GetModuleFileNameW(NULL, modpath, buflen);

        if (rc == 0)

        {

            allocator.Free(modpath);

            BAIL_MACRO(errcodeFromWinApi(), NULL);

        } /* if */

        if (rc < buflen)

        {

            buflen = rc;

            break;

        } /* if */

        buflen *= 2;

    } /* while */

    if (buflen > 0)  /* just in case... */

    {

        WCHAR *ptr = (modpath + buflen) - 1;

        while (ptr != modpath)

        {

            if (*ptr == '\\')

                break;

            ptr--;

        } /* while */

        if ((ptr == modpath) && (*ptr != '\\'))

            __PHYSFS_setError(PHYSFS_ERR_OTHER_ERROR);  /* oh well. */

        else

        {

            *(ptr + 1) = '\0';  /* chop off filename. */

            retval = unicodeToUtf8Heap(modpath);

        } /* else */

    } /* else */

    allocator.Free(modpath);

    return retval;   /* w00t. */

} /* __PHYSFS_platformCalcBaseDir */

char *__PHYSFS_platformCalcPrefDir(const char *org, const char *app)

{

    WCHAR path[MAX_PATH];

    if (!SUCCEEDED(SHGetFolderPathW(NULL, CSIDL_APPDATA | CSIDL_FLAG_CREATE,

                                   NULL, 0, path)))

        BAIL_MACRO(PHYSFS_ERR_OS_ERROR, NULL);

} /* __PHYSFS_platformCalcPrefDir */

char *__PHYSFS_platformGetUserName(void)

{

    DWORD bufsize = 0;

    char *retval = NULL;

    if (GetUserNameW(NULL, &bufsize) == 0)  /* This SHOULD fail. */

    {

        LPWSTR wbuf = (LPWSTR) __PHYSFS_smallAlloc(bufsize * sizeof (WCHAR));

        BAIL_IF_MACRO(!wbuf, PHYSFS_ERR_OUT_OF_MEMORY, NULL);

        if (GetUserNameW(wbuf, &bufsize) == 0)  /* ?! */

            __PHYSFS_setError(errcodeFromWinApi());