/* ----------------------------------------------------------------------- *
 *
 *   Copyright 2003 Lars Munch Christensen - All Rights Reserved
 *   Copyright 1998-2008 H. Peter Anvin - All Rights Reserved
 *
 *   Based on the Linux installer program for SYSLINUX by H. Peter Anvin
 *
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation, Inc., 53 Temple Place Ste 330,
 *   Boston MA 02111-1307, USA; either version 2 of the License, or
 *   (at your option) any later version; incorporated herein by reference.
 *
 * ----------------------------------------------------------------------- */

/*
 * syslinux-mingw.c - Win2k/WinXP installer program for SYSLINUX
 */

#include <windows.h>
#include <stdio.h>
#include <ctype.h>

#include "syslinux.h"
#include "libfat.h"

#ifdef __GNUC__
# define noreturn void __attribute__((noreturn))
#else
# define noreturn void
#endif

void error(char *msg);

/* Begin stuff for MBR code */

#include <winioctl.h>

#define SECTOR_SIZE 512
#define PART_TABLE  0x1be
#define PART_SIZE   0x10
#define PART_COUNT  4
#define PART_ACTIVE 0x80

// The following struct should be in the ntddstor.h file, but I didn't have it.
// TODO: Make this a conditional compilation
typedef struct _STORAGE_DEVICE_NUMBER {
    DEVICE_TYPE DeviceType;
    ULONG DeviceNumber;
    ULONG PartitionNumber;
} STORAGE_DEVICE_NUMBER, *PSTORAGE_DEVICE_NUMBER;

BOOL GetStorageDeviceNumberByHandle(HANDLE handle,
				    const STORAGE_DEVICE_NUMBER * sdn)
{
    BOOL result = FALSE;
    DWORD count;

    if (DeviceIoControl(handle, IOCTL_STORAGE_GET_DEVICE_NUMBER, NULL,
			0, (LPVOID) sdn, sizeof(*sdn), &count, NULL)) {
	result = TRUE;
    } else {
	error("GetDriveNumber: DeviceIoControl failed");
    }

    return (result);
}

int GetBytesPerSector(HANDLE drive)
{
    int result = 0;
    DISK_GEOMETRY g;
    DWORD count;

    if (DeviceIoControl(drive, IOCTL_DISK_GET_DRIVE_GEOMETRY, NULL, 0,
			&g, sizeof(g), &count, NULL)) {
	result = g.BytesPerSector;
    }

    return (result);
}

BOOL FixMBR(int driveNum, int partitionNum, int write_mbr, int set_active)
{
    BOOL result = TRUE;
    HANDLE drive;

    char driveName[128];

    sprintf(driveName, "\\\\.\\PHYSICALDRIVE%d", driveNum);

    drive = CreateFile(driveName,
		       GENERIC_READ | GENERIC_WRITE,
		       FILE_SHARE_WRITE | FILE_SHARE_READ,
		       NULL, OPEN_EXISTING, 0, NULL);

    if (drive == INVALID_HANDLE_VALUE) {
	error("Accessing physical drive");
	result = FALSE;
    }

    if (result) {
	unsigned char sector[SECTOR_SIZE];
	DWORD howMany;

	if (GetBytesPerSector(drive) != SECTOR_SIZE) {
	    fprintf(stderr,
		    "Error: Sector size of this drive is %d; must be %d\n",
		    GetBytesPerSector(drive), SECTOR_SIZE);
	    result = FALSE;
	}

	if (result) {
	    if (ReadFile(drive, sector, sizeof(sector), &howMany, NULL) == 0) {
		error("Reading raw drive");
		result = FALSE;
	    } else if (howMany != sizeof(sector)) {
		fprintf(stderr,
			"Error: ReadFile on drive only got %d of %d bytes\n",
			(int)howMany, sizeof(sector));
		result = FALSE;
	    }
	}
	// Copy over the MBR code if specified (-m)
	if (write_mbr) {
	    if (result) {
		if (syslinux_mbr_len >= PART_TABLE) {
		    fprintf(stderr, "Error: MBR will not fit; not writing\n");
		    result = FALSE;
		} else {
		    memcpy(sector, syslinux_mbr, syslinux_mbr_len);
		}
	    }
	}
	// Check that our partition is active if specified (-a)
	if (set_active) {
	    if (sector[PART_TABLE + (PART_SIZE * (partitionNum - 1))] != 0x80) {
		int p;
		for (p = 0; p < PART_COUNT; p++)
		    sector[PART_TABLE + (PART_SIZE * p)] =
			(p == partitionNum - 1 ? 0x80 : 0);
	    }
	}

	if (result) {
	    SetFilePointer(drive, 0, NULL, FILE_BEGIN);

	    if (WriteFile(drive, sector, sizeof(sector), &howMany, NULL) == 0) {
		error("Writing MBR");
		result = FALSE;
	    } else if (howMany != sizeof(sector)) {
		fprintf(stderr,
			"Error: WriteFile on drive only wrote %d of %d bytes\n",
			(int)howMany, sizeof(sector));
		result = FALSE;
	    }
	}

	if (!CloseHandle(drive)) {
	    error("CloseFile on drive");
	    result = FALSE;
	}
    }

    return (result);
}

/* End stuff for MBR code */

const char *program;		/* Name of program */
const char *drive;		/* Drive to install to */

/*
 * Check Windows version.
 *
 * On Windows Me/98/95 you cannot open a directory, physical disk, or
 * volume using CreateFile.
 */
int checkver(void)
{
    OSVERSIONINFO osvi;

    osvi.dwOSVersionInfoSize = sizeof(OSVERSIONINFO);
    GetVersionEx(&osvi);

    return (osvi.dwPlatformId == VER_PLATFORM_WIN32_NT) &&
	((osvi.dwMajorVersion > 4) ||
	 ((osvi.dwMajorVersion == 4) && (osvi.dwMinorVersion == 0)));
}

/*
 * Windows error function
 */
void error(char *msg)
{
    LPVOID lpMsgBuf;

    /* Format the Windows error message */
    FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS, NULL, GetLastError(), MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),	// Default language
		  (LPTSTR) & lpMsgBuf, 0, NULL);

    /* Print it */
    fprintf(stderr, "%s: %s", msg, (char *)lpMsgBuf);

    /* Free the buffer */
    LocalFree(lpMsgBuf);
}

/*
 * Wrapper for ReadFile suitable for libfat
 */
int libfat_readfile(intptr_t pp, void *buf, size_t secsize,
		    libfat_sector_t sector)
{
    uint64_t offset = (uint64_t) sector * secsize;
    LONG loword = (LONG) offset;
    LONG hiword = (LONG) (offset >> 32);
    LONG hiwordx = hiword;
    DWORD bytes_read;

    if (SetFilePointer((HANDLE) pp, loword, &hiwordx, FILE_BEGIN) != loword ||
	hiword != hiwordx ||
	!ReadFile((HANDLE) pp, buf, secsize, &bytes_read, NULL) ||
	bytes_read != secsize) {
	fprintf(stderr, "Cannot read sector %u\n", sector);
	exit(1);
    }

    return secsize;
}

noreturn usage(void)
{
    fprintf(stderr,
	    "Usage: syslinux.exe [-sfmar][-d directory] <drive>: [bootsecfile]\n");
    exit(1);
}

int main(int argc, char *argv[])
{
    HANDLE f_handle, d_handle;
    DWORD bytes_read;
    DWORD bytes_written;
    DWORD drives;
    UINT drive_type;

    static unsigned char sectbuf[512];
    char **argp, *opt;
    static char drive_name[] = "\\\\.\\?:";
    static char drive_root[] = "?:\\";
    static char ldlinux_name[] = "?:\\ldlinux.sys";
    const char *errmsg;
    struct libfat_filesystem *fs;
    libfat_sector_t s, *secp, sectors[65];	/* 65 is maximum possible */
    uint32_t ldlinux_cluster;
    int nsectors;
    const char *bootsecfile = NULL;
    const char *subdir = NULL;

    int force = 0;		/* -f (force) option */
    int mbr = 0;		/* -m (MBR) option */
    int setactive = 0;		/* -a (set partition active) */
    int stupid = 0;		/* -s (stupid) option */
    int raid_mode = 0;		/* -r (RAID) option */

    (void)argc;

    if (!checkver()) {
	fprintf(stderr,
		"You need to be running at least Windows NT; use syslinux.com instead.\n");
	exit(1);
    }

    program = argv[0];
    drive = NULL;

    for (argp = argv + 1; *argp; argp++) {
	if (**argp == '-') {
	    opt = *argp + 1;
	    if (!*opt)
		usage();

	    while (*opt) {
		switch (*opt) {
		case 's':	/* Use "safe, slow and stupid" code */
		    stupid = 1;
		    break;
		case 'r':	/* RAID mode */
		    raid_mode = 1;
		    break;
		case 'f':	/* Force install */
		    force = 1;
		    break;
		case 'm':	/* Install MBR */
		    mbr = 1;
		    break;
		case 'a':	/* Mark this partition active */
		    setactive = 1;
		    break;
		case 'd':
		    if (argp[1])
			subdir = *++argp;
		    break;
		default:
		    usage();
		    break;
		}
		opt++;
	    }
	} else {
	    if (bootsecfile)
		usage();
	    else if (drive)
		bootsecfile = *argp;
	    else
		drive = *argp;
	}
    }

    if (!drive || !isalpha(drive[0]) || drive[1] != ':' || drive[2])
	usage();

    /* Test if drive exists */
    drives = GetLogicalDrives();
    if (!(drives & (1 << (tolower(drive[0]) - 'a')))) {
	fprintf(stderr, "No such drive %c:\n", drive[0]);
	exit(1);
    }

    /* Determines the drive type */
    drive_name[4] = drive[0];
    ldlinux_name[0] = drive[0];
    drive_root[0] = drive[0];
    drive_type = GetDriveType(drive_root);

    /* Test for removeable media */
    if ((drive_type == DRIVE_FIXED) && (force == 0)) {
	fprintf(stderr, "Not a removable drive (use -f to override) \n");
	exit(1);
    }

    /* Test for unsupported media */
    if ((drive_type != DRIVE_FIXED) && (drive_type != DRIVE_REMOVABLE)) {
	fprintf(stderr, "Unsupported media\n");
	exit(1);
    }

    /*
     * First open the drive
     */
    d_handle = CreateFile(drive_name, GENERIC_READ | GENERIC_WRITE,
			  FILE_SHARE_READ | FILE_SHARE_WRITE,
			  NULL, OPEN_EXISTING, 0, NULL);

    if (d_handle == INVALID_HANDLE_VALUE) {
	error("Could not open drive");
	exit(1);
    }

    /*
     * Make sure we can read the boot sector
     */
    if (!ReadFile(d_handle, sectbuf, 512, &bytes_read, NULL)) {
	error("Reading boot sector");
	exit(1);
    }
    if (bytes_read != 512) {
	fprintf(stderr, "Could not read the whole boot sector\n");
	exit(1);
    }

    /* Check to see that what we got was indeed an MS-DOS boot sector/superblock */
    if ((errmsg = syslinux_check_bootsect(sectbuf))) {
	fprintf(stderr, "%s\n", errmsg);
	exit(1);
    }

    /* Change to normal attributes to enable deletion */
    /* Just ignore error if the file do not exists */
    SetFileAttributes(ldlinux_name, FILE_ATTRIBUTE_NORMAL);

    /* Delete the file */
    /* Just ignore error if the file do not exists */
    DeleteFile(ldlinux_name);

    /* Create ldlinux.sys file */
    f_handle = CreateFile(ldlinux_name, GENERIC_READ | GENERIC_WRITE,
			  FILE_SHARE_READ | FILE_SHARE_WRITE,
			  NULL, CREATE_ALWAYS,
			  FILE_ATTRIBUTE_READONLY | FILE_ATTRIBUTE_SYSTEM |
			  FILE_ATTRIBUTE_HIDDEN, NULL);

    if (f_handle == INVALID_HANDLE_VALUE) {
	error("Unable to create ldlinux.sys");
	exit(1);
    }

    /* Write ldlinux.sys file */
    if (!WriteFile
	(f_handle, syslinux_ldlinux, syslinux_ldlinux_len, &bytes_written,
	 NULL)) {
	error("Could not write ldlinux.sys");
	exit(1);
    }

    if (bytes_written != syslinux_ldlinux_len) {
	fprintf(stderr, "Could not write whole ldlinux.sys\n");
	exit(1);
    }

    /* Now flush the media */
    if (!FlushFileBuffers(f_handle)) {
	error("FlushFileBuffers failed");
	exit(1);
    }

    /* Map the file (is there a better way to do this?) */
    fs = libfat_open(libfat_readfile, (intptr_t) d_handle);
    ldlinux_cluster = libfat_searchdir(fs, 0, "LDLINUX SYS", NULL);
    secp = sectors;
    nsectors = 0;
    s = libfat_clustertosector(fs, ldlinux_cluster);
    while (s && nsectors < 65) {
	*secp++ = s;
	nsectors++;
	s = libfat_nextsector(fs, s);
    }
    libfat_close(fs);

    /*
     * Patch ldlinux.sys and the boot sector
     */
    syslinux_patch(sectors, nsectors, stupid, raid_mode);

    /*
     * Rewrite the file
     */
    if (SetFilePointer(f_handle, 0, NULL, FILE_BEGIN) != 0 ||
	!WriteFile(f_handle, syslinux_ldlinux, syslinux_ldlinux_len,
		   &bytes_written, NULL)
	|| bytes_written != syslinux_ldlinux_len) {
	error("Could not write ldlinux.sys");
	exit(1);
    }

    /* If desired, fix the MBR */
    if (mbr || setactive) {
	STORAGE_DEVICE_NUMBER sdn;
	if (GetStorageDeviceNumberByHandle(d_handle, &sdn)) {
	    if (!FixMBR(sdn.DeviceNumber, sdn.PartitionNumber, mbr, setactive)) {
		fprintf(stderr,
			"Did not successfully update the MBR; continuing...\n");
	    }
	} else {
	    fprintf(stderr,
		    "Could not find device number for updating MBR; continuing...\n");
	}
    }

    /* Close file */
    CloseHandle(f_handle);

    /* Move the file to the desired location */
    if (subdir) {
	char new_ldlinux_name[strlen(subdir) + 16];
	char *cp = new_ldlinux_name + 3;
	const char *sd;
	int slash = 1;

	new_ldlinux_name[0] = drive[0];
	new_ldlinux_name[1] = ':';
	new_ldlinux_name[2] = '\\';

	for (sd = subdir; *sd; sd++) {
	    char c = *sd;

	    if (c == '/' || c == '\\') {
		if (slash)
		    continue;
		c = '\\';
		slash = 1;
	    } else {
		slash = 0;
	    }

	    *cp++ = c;
	}

	/* Skip if subdirectory == root */
	if (cp > new_ldlinux_name + 3) {
	    if (!slash)
		*cp++ = '\\';

	    memcpy(cp, "ldlinux.sys", 12);

	    /* Delete any previous file */
	    SetFileAttributes(new_ldlinux_name, FILE_ATTRIBUTE_NORMAL);
	    DeleteFile(new_ldlinux_name);
	    if (!MoveFile(ldlinux_name, new_ldlinux_name))
		SetFileAttributes(ldlinux_name, FILE_ATTRIBUTE_READONLY |
				  FILE_ATTRIBUTE_SYSTEM |
				  FILE_ATTRIBUTE_HIDDEN);
	    else
		SetFileAttributes(new_ldlinux_name, FILE_ATTRIBUTE_READONLY |
				  FILE_ATTRIBUTE_SYSTEM |
				  FILE_ATTRIBUTE_HIDDEN);
	}
    }

    /* Make the syslinux boot sector */
    syslinux_make_bootsect(sectbuf);

    /* Write the syslinux boot sector into the boot sector */
    if (bootsecfile) {
	f_handle = CreateFile(bootsecfile, GENERIC_READ | GENERIC_WRITE,
			      FILE_SHARE_READ | FILE_SHARE_WRITE,
			      NULL, CREATE_ALWAYS,
			      FILE_ATTRIBUTE_ARCHIVE, NULL);
	if (f_handle == INVALID_HANDLE_VALUE) {
	    error("Unable to create bootsector file");
	    exit(1);
	}
	if (!WriteFile(f_handle, sectbuf, 512, &bytes_written, NULL)) {
	    error("Could not write boot sector file");
	    exit(1);
	}
	CloseHandle(f_handle);
    } else {
	SetFilePointer(d_handle, 0, NULL, FILE_BEGIN);
	WriteFile(d_handle, sectbuf, 512, &bytes_written, NULL);
    }

    if (bytes_written != 512) {
	fprintf(stderr, "Could not write the whole boot sector\n");
	exit(1);
    }

    /* Close file */
    CloseHandle(d_handle);

    /* Done! */
    return 0;
}