/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

/**
 *  Manifest Format
 *  ---------------
 *
 *  contents = 1*( line )
 *  line     = method LWS *( param LWS ) CRLF
 *  CRLF     = "\r\n"
 *  LWS      = 1*( " " | "\t" )
 *
 *  Available methods for the manifest file:
 *
 *  updatev2.manifest
 *  -----------------
 *  method   = "add" | "add-if" | "patch" | "patch-if" | "remove" |
 *             "rmdir" | "rmrfdir" | type
 *
 *  'type' is the update type (e.g. complete or partial) and when present MUST
 *  be the first entry in the update manifest. The type is used to support
 *  downgrades by causing the actions defined in precomplete to be performed.
 *
 *  updatev3.manifest
 *  -----------------
 *  method   = "add" | "add-if" | "add-if-not" | "patch" | "patch-if" |
 *             "remove" | "rmdir" | "rmrfdir" | type
 *
 *  'add-if-not' adds a file if it doesn't exist.
 *
 *  precomplete
 *  -----------
 *  method   = "remove" | "rmdir"
 */
#include "bspatch.h"
#include "progressui.h"
#include "archivereader.h"
#include "readstrings.h"
#include "errors.h"
#include "bzlib.h"
#include <thread>
#include <vector>

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <stdarg.h>

#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <limits.h>
#include <errno.h>
#include <algorithm>
#include <memory>

#include <config_version.h>

#include "updatelogging.h"

#include <onlineupdate/mozilla/Compiler.h>
#include <onlineupdate/mozilla/Types.h>

#ifdef _WIN32
#include <comphelper/windowsStart.hxx>
#include "uachelper.h"
#include "pathhash.h"

// TODO:moggi taken from the mozilla code -- find a better solution
#define INVALID_APPLYTO_DIR_ERROR 74
#define REMOVE_FILE_SPEC_ERROR 71
#define INVALID_APPLYTO_DIR_STAGED_ERROR 72

#endif


// Amount of the progress bar to use in each of the 3 update stages,
// should total 100.0.
#define PROGRESS_PREPARE_SIZE 20.0f
#define PROGRESS_EXECUTE_SIZE 75.0f
#define PROGRESS_FINISH_SIZE   5.0f

// Amount of time in ms to wait for the parent process to close
#ifdef _WIN32
#define PARENT_WAIT 5000
#endif

#if defined(MACOSX)
// These functions are defined in launchchild_osx.mm
void CleanupElevatedMacUpdate(bool aFailureOccurred);
bool IsOwnedByGroupAdmin(const char* aAppBundle);
bool IsRecursivelyWritable(const char* aPath);
void LaunchChild(int argc, const char** argv);
void LaunchMacPostProcess(const char* aAppBundle);
bool ObtainUpdaterArguments(int* argc, char*** argv);
bool ServeElevatedUpdate(int argc, const char** argv);
void SetGroupOwnershipAndPermissions(const char* aAppBundle);
struct UpdateServerThreadArgs
{
    int argc;
    const NS_tchar** argv;
};
#endif

#ifndef SSIZE_MAX
# define SSIZE_MAX LONG_MAX
#endif

// We want to use execv to invoke the callback executable on platforms where
// we were launched using execv.  See nsUpdateDriver.cpp.
#if defined(UNIX) && !defined(MACOSX)
#define USE_EXECV
#endif

#if defined(VERIFY_MAR_SIGNATURE) && !defined(_WIN32) && !defined(MACOSX)
#include <nss.h>
#include <nspr.h>
#endif

#ifdef _WIN32
#ifdef MAINTENANCE_SERVICE
#include "registrycertificates.h"
#endif
BOOL PathAppendSafe(LPWSTR base, LPCWSTR extra);
BOOL PathGetSiblingFilePath(LPWSTR destinationBuffer,
                            LPCWSTR siblingFilePath,
                            LPCWSTR newFileName);
#include "updatehelper.h"

// Closes the handle if valid and if the updater is elevated returns with the
// return code specified. This prevents multiple launches of the callback
// application by preventing the elevated process from launching the callback.
#define EXIT_WHEN_ELEVATED(path, handle, retCode) \
{ \
    if (handle != INVALID_HANDLE_VALUE) { \
        CloseHandle(handle); \
    } \
    if (_waccess(path, F_OK) == 0 && NS_tremove(path) != 0) { \
        LogFinish(); \
        return retCode; \
    } \
}
#endif

//-----------------------------------------------------------------------------

// This variable lives in libbz2.  It's declared in bzlib_private.h, so we just
// declare it here to avoid including that entire header file.
#if defined __GNUC__
extern "C"  __attribute__((visibility("default"))) unsigned int BZ2_crc32Table[256];
#elif defined(__SUNPRO_C) || defined(__SUNPRO_CC)
extern "C" __global unsigned int BZ2_crc32Table[256];
#else
extern "C" unsigned int BZ2_crc32Table[256];
#endif

static unsigned int
crc32(const unsigned char *buf, unsigned int len)
{
    unsigned int crc = 0xffffffffL;

    const unsigned char *end = buf + len;
    for (; buf != end; ++buf)
        crc = (crc << 8) ^ BZ2_crc32Table[(crc >> 24) ^ *buf];

    crc = ~crc;
    return crc;
}

//-----------------------------------------------------------------------------

// A simple stack based container for a FILE struct that closes the
// file descriptor from its destructor.
class AutoFile
{
public:
    explicit AutoFile(FILE* file = nullptr)
        : mFile(file)
    {
    }

    ~AutoFile()
    {
        if (mFile != nullptr)
            fclose(mFile);
    }

    AutoFile &operator=(FILE* file)
    {
        if (mFile != 0)
            fclose(mFile);
        mFile = file;
        return *this;
    }

    operator FILE*()
    {
        return mFile;
    }

    FILE* get()
    {
        return mFile;
    }

private:
    FILE* mFile;
};

struct MARChannelStringTable
{
    MARChannelStringTable()
    {
        MARChannelID[0] = '\0';
    }

    char MARChannelID[MAX_TEXT_LEN];
};

//-----------------------------------------------------------------------------

static NS_tchar* gPatchDirPath;
static NS_tchar gInstallDirPath[MAXPATHLEN];
static NS_tchar gWorkingDirPath[MAXPATHLEN];
static bool gSucceeded = false;
static bool sStagedUpdate = false;
static bool sReplaceRequest = false;
static bool sUsingService = false;

#ifdef _WIN32
// The current working directory specified in the command line.
static NS_tchar* gDestPath;
static NS_tchar gCallbackRelPath[MAXPATHLEN];
static NS_tchar gCallbackBackupPath[MAXPATHLEN];
static NS_tchar gDeleteDirPath[MAXPATHLEN];
#endif

static const NS_tchar kWhitespace[] = NS_T(" \t");
static const NS_tchar kNL[] = NS_T("\r\n");
static const NS_tchar kQuote[] = NS_T("\"");

static NS_tchar*
mstrtok(const NS_tchar *delims, NS_tchar **str)
{
    if (!*str || !**str)
    {
        *str = nullptr;
        return nullptr;
    }

    // skip leading "whitespace"
    NS_tchar *ret = *str;
    const NS_tchar *d;
    do
    {
        for (d = delims; *d != NS_T('\0'); ++d)
        {
            if (*ret == *d)
            {
                ++ret;
                break;
            }
        }
    }
    while (*d);

    if (!*ret)
    {
        *str = ret;
        return nullptr;
    }

    NS_tchar *i = ret;
    do
    {
        for (d = delims; *d != NS_T('\0'); ++d)
        {
            if (*i == *d)
            {
                *i = NS_T('\0');
                *str = ++i;
                return ret;
            }
        }
        ++i;
    }
    while (*i);

    *str = nullptr;
    return ret;
}

#if defined(_WIN32) && defined(MAINTENANCE_SERVICE)
static bool
EnvHasValue(const char *name)
{
    const char *val = getenv(name);
    return (val && *val);
}
#endif

/**
 * Converts a relative update path to an absolute path related to the working
 * or install directory. Allocates a new NS_tchar[] based path!
 *
 * @param  relpath
 *         The relative path to convert to a full path.
 * @return valid filesystem full path or nullptr if memory allocation fails.
 */
static NS_tchar*
new_absolute_path(const NS_tchar *relpath)
{
    NS_tchar *destpath = sStagedUpdate ? gWorkingDirPath : gInstallDirPath;
    size_t lendestpath = NS_tstrlen(destpath);
    size_t lenrelpath = NS_tstrlen(relpath);
    NS_tchar *s = new NS_tchar[lendestpath + lenrelpath + 2];

    NS_tchar *c = s;

    NS_tstrcpy(c, destpath);
    c += lendestpath;
    NS_tstrcat(c, NS_T("/"));
    c++;

    NS_tstrcat(c, relpath);
    c += lenrelpath;
    *c = NS_T('\0');
    return s;
}

namespace {

bool is_userprofile_in_instdir()
{
    return false;
    /*
    // the algorithm is:
    // 1.) if userprofile path length is smaller than installation dir,
    //      the profile is surely not in instdir
    // 2.) else comparing the two paths looking only at the installation dir
    //      characters should yield an equal string
    NS_tchar userprofile[MAXPATHLEN];
    NS_tstrcpy(userprofile, gPatchDirPath);
    NS_tchar *slash = (NS_tchar *) NS_tstrrchr(userprofile, NS_T('/'));
    if (slash)
        *slash = NS_T('\0');

    size_t userprofile_len = NS_tstrlen(userprofile);
    size_t installdir_len = NS_tstrlen(gInstallDirPath);

    if (userprofile_len < installdir_len)
        return false;

    return NS_tstrncmp(userprofile, gInstallDirPath, installdir_len) == 0;
    */
}

}

/**
 * Get a pointer in the absolute path, relative to the working or install
 * directory. Returns itself, if not absolute or outside of the directory.
 *
 * @param  abs_path
 *         An absolute path.
 * return pointer to the location within fullpath where the relative path starts
 *        or fullpath itself if it already looks relative.
 */
static const NS_tchar*
get_relative_offset(const NS_tchar *abs_path)
{
    // If the path isn't absolute, just return it as-is.
#ifdef _WIN32
    if (abs_path[1] != ':' && abs_path[2] != '\\')
    {
#else
    if (abs_path[0] != '/')
    {
#endif
        return abs_path;
    }

    NS_tchar *prefix = sStagedUpdate ? gWorkingDirPath : gInstallDirPath;

    size_t len = NS_tstrlen(prefix);
    if (NS_tstrlen(abs_path) <= len)
        return abs_path;
    if (0 != strncmp(abs_path, prefix, len))
        return abs_path;
    return abs_path + len + 1;
}

/**
 * Gets the platform specific path and performs simple checks to the path. If
 * the path checks don't pass nullptr will be returned.
 *
 * @param  line
 *         The line from the manifest that contains the path.
 * @param  isdir
 *         Whether the path is a directory path. Defaults to false.
 * @return valid filesystem path or nullptr if the path checks fail.
 */
static NS_tchar*
get_valid_path(NS_tchar **line, bool isdir = false)
{
    NS_tchar *path = mstrtok(kQuote, line);
    if (!path)
    {
        LOG(("get_valid_path: unable to determine path: " LOG_S, line));
        return nullptr;
    }

    // All paths must be relative from the current working directory
    if (path[0] == NS_T('/'))
    {
        LOG(("get_valid_path: path must be relative: " LOG_S, path));
        return nullptr;
    }

#ifdef _WIN32
    // All paths must be relative from the current working directory
    if (path[0] == NS_T('\\') || path[1] == NS_T(':'))
    {
        LOG(("get_valid_path: path must be relative: " LOG_S, path));
        return nullptr;
    }
#endif

    if (isdir)
    {
        // Directory paths must have a trailing forward slash.
        if (path[NS_tstrlen(path) - 1] != NS_T('/'))
        {
            LOG(("get_valid_path: directory paths must have a trailing forward " \
                 "slash: " LOG_S, path));
            return nullptr;
        }

        // Remove the trailing forward slash because stat on Windows will return
        // ENOENT if the path has a trailing slash.
        path[NS_tstrlen(path) - 1] = NS_T('\0');
    }

    // Don't allow relative paths that resolve to a parent directory.
    if (NS_tstrstr(path, NS_T("..")) != nullptr)
    {
        LOG(("get_valid_path: paths must not contain '..': " LOG_S, path));
        return nullptr;
    }

    return path;
}

static NS_tchar*
get_quoted_path(const NS_tchar *path)
{
    size_t lenQuote = NS_tstrlen(kQuote);
    size_t lenPath = NS_tstrlen(path);
    size_t len = lenQuote + lenPath + lenQuote + 1;

    NS_tchar *s = (NS_tchar *) malloc(len * sizeof(NS_tchar));
    if (!s)
        return nullptr;

    NS_tchar *c = s;
    NS_tstrcpy(c, kQuote);
    c += lenQuote;
    NS_tstrcat(c, path);
    c += lenPath;
    NS_tstrcat(c, kQuote);
    c += lenQuote;
    *c = NS_T('\0');
    c++;
    return s;
}

static void ensure_write_permissions(const NS_tchar *path)
{
#ifdef _WIN32
    (void) _wchmod(path, _S_IREAD | _S_IWRITE);
#else
    struct stat fs;
    if (!stat(path, &fs) && !(fs.st_mode & S_IWUSR))
    {
        (void)chmod(path, fs.st_mode | S_IWUSR);
    }
#endif
}

static int ensure_remove(const NS_tchar *path)
{
    ensure_write_permissions(path);
    int rv = NS_tremove(path);
    if (rv)
        LOG(("ensure_remove: failed to remove file: " LOG_S ", rv: %d, err: %d",
             path, rv, errno));
    return rv;
}

// Remove the directory pointed to by path and all of its files and sub-directories.
static int ensure_remove_recursive(const NS_tchar *path,
                                   bool continueEnumOnFailure = false)
{
    // We use lstat rather than stat here so that we can successfully remove
    // symlinks.
    struct NS_tstat_t sInfo;
    int rv = NS_tlstat(path, &sInfo);
    if (rv)
    {
        // This error is benign
        return rv;
    }
    if (!S_ISDIR(sInfo.st_mode))
    {
        return ensure_remove(path);
    }

    NS_tDIR *dir;
    NS_tdirent *entry;

    dir = NS_topendir(path);
    if (!dir)
    {
        LOG(("ensure_remove_recursive: unable to open directory: " LOG_S
             ", rv: %d, err: %d", path, rv, errno));
        return rv;
    }

    while ((entry = NS_treaddir(dir)) != 0)
    {
        if (NS_tstrcmp(entry->d_name, NS_T(".")) &&
                NS_tstrcmp(entry->d_name, NS_T("..")))
        {
            NS_tchar childPath[MAXPATHLEN];
            NS_tsnprintf(childPath, sizeof(childPath)/sizeof(childPath[0]),
                         NS_T("%s/%s"), path, entry->d_name);
            rv = ensure_remove_recursive(childPath);
            if (rv && !continueEnumOnFailure)
            {
                break;
            }
        }
    }

    NS_tclosedir(dir);

    if (rv == OK)
    {
        ensure_write_permissions(path);
        rv = NS_trmdir(path);
        if (rv)
        {
            LOG(("ensure_remove_recursive: unable to remove directory: " LOG_S
                 ", rv: %d, err: %d", path, rv, errno));
        }
    }
    return rv;
}

static bool is_read_only(const NS_tchar *flags)
{
    size_t length = NS_tstrlen(flags);
    if (length == 0)
        return false;

    // Make sure the string begins with "r"
    if (flags[0] != NS_T('r'))
        return false;

    // Look for "r+" or "r+b"
    if (length > 1 && flags[1] == NS_T('+'))
        return false;

    // Look for "rb+"
    if (NS_tstrcmp(flags, NS_T("rb+")) == 0)
        return false;

    return true;
}

static FILE* ensure_open(const NS_tchar *path, const NS_tchar *flags, unsigned int options)
{
    ensure_write_permissions(path);
    FILE* f = NS_tfopen(path, flags);
    if (is_read_only(flags))
    {
        // Don't attempt to modify the file permissions if the file is being opened
        // in read-only mode.
        return f;
    }
    if (NS_tchmod(path, options) != 0)
    {
        if (f != nullptr)
        {
            fclose(f);
        }
        return nullptr;
    }
    struct NS_tstat_t ss;
    if (NS_tstat(path, &ss) != 0 || ss.st_mode != options)
    {
        if (f != nullptr)
        {
            fclose(f);
        }
        return nullptr;
    }
    return f;
}

// Ensure that the directory containing this file exists.
static int ensure_parent_dir(const NS_tchar *path)
{
    int rv = OK;

    NS_tchar *slash = (NS_tchar *) NS_tstrrchr(path, NS_T('/'));
    if (slash)
    {
        *slash = NS_T('\0');
        rv = ensure_parent_dir(path);
        // Only attempt to create the directory if we're not at the root
        if (rv == OK && *path)
        {
            rv = NS_tmkdir(path, 0755);
            // If the directory already exists, then ignore the error.
            if (rv < 0 && errno != EEXIST)
            {
                LOG(("ensure_parent_dir: failed to create directory: " LOG_S ", " \
                     "err: %d", path, errno));
                rv = WRITE_ERROR;
            }
            else
            {
                rv = OK;
            }
        }
        *slash = NS_T('/');
    }
    return rv;
}

#ifdef UNIX
static int ensure_copy_symlink(const NS_tchar *path, const NS_tchar *dest)
{
    // Copy symlinks by creating a new symlink to the same target
    NS_tchar target[MAXPATHLEN + 1] = {NS_T('\0')};
    int rv = readlink(path, target, MAXPATHLEN);
    if (rv == -1)
    {
        LOG(("ensure_copy_symlink: failed to read the link: " LOG_S ", err: %d",
             path, errno));
        return READ_ERROR;
    }
    rv = symlink(target, dest);
    if (rv == -1)
    {
        LOG(("ensure_copy_symlink: failed to create the new link: " LOG_S ", target: " LOG_S " err: %d",
             dest, target, errno));
        return READ_ERROR;
    }
    return 0;
}
#endif

// Copy the file named path onto a new file named dest.
static int ensure_copy(const NS_tchar *path, const NS_tchar *dest)
{
#ifdef _WIN32
    // Fast path for Windows
    bool result = CopyFileW(path, dest, false);
    if (!result)
    {
        LOG(("ensure_copy: failed to copy the file " LOG_S " over to " LOG_S ", lasterr: %x",
             path, dest, GetLastError()));
        return WRITE_ERROR_FILE_COPY;
    }
    return OK;
#else
    struct NS_tstat_t ss;
    int rv = NS_tlstat(path, &ss);
    if (rv)
    {
        LOG(("ensure_copy: failed to read file status info: " LOG_S ", err: %d",
             path, errno));
        return READ_ERROR;
    }

#ifdef UNIX
    if (S_ISLNK(ss.st_mode))
    {
        return ensure_copy_symlink(path, dest);
    }
#endif

    AutoFile infile(ensure_open(path, NS_T("rb"), ss.st_mode));
    if (!infile)
    {
        LOG(("ensure_copy: failed to open the file for reading: " LOG_S ", err: %d",
             path, errno));
        return READ_ERROR;
    }
    AutoFile outfile(ensure_open(dest, NS_T("wb"), ss.st_mode));
    if (!outfile)
    {
        LOG(("ensure_copy: failed to open the file for writing: " LOG_S ", err: %d",
             dest, errno));
        return WRITE_ERROR;
    }

    // This block size was chosen pretty arbitrarily but seems like a reasonable
    // compromise. For example, the optimal block size on a modern macOS machine
    // is 100k */
    const int blockSize = 32 * 1024;
    void* buffer = malloc(blockSize);
    if (!buffer)
        return UPDATER_MEM_ERROR;

    while (!feof(infile.get()))
    {
        size_t read = fread(buffer, 1, blockSize, infile);
        if (ferror(infile.get()))
        {
            LOG(("ensure_copy: failed to read the file: " LOG_S ", err: %d",
                 path, errno));
            free(buffer);
            return READ_ERROR;
        }

        size_t written = 0;

        while (written < read)
        {
            size_t nCount = read - written;
            size_t chunkWritten = fwrite(buffer, 1, nCount, outfile);
            if (chunkWritten != nCount)
            {
                LOG(("ensure_copy: failed to write the file: " LOG_S ", err: %d",
                     dest, errno));
                free(buffer);
                return WRITE_ERROR_FILE_COPY;
            }

            written += chunkWritten;
        }
    }

    rv = NS_tchmod(dest, ss.st_mode);

    free(buffer);
    return rv;
#endif
}

template <unsigned N>
struct copy_recursive_skiplist
{
    NS_tchar paths[N][MAXPATHLEN];

    void append(unsigned index, const NS_tchar *path, const NS_tchar *suffix)
    {
        NS_tsnprintf(paths[index], MAXPATHLEN, NS_T("%s/%s"), path, suffix);
    }

    void append(unsigned index, const NS_tchar* path)
    {
        NS_tstrcpy(paths[index], path);
    }

    bool find(const NS_tchar *path)
    {
        for (int i = 0; i < static_cast<int>(N); ++i)
        {
            if (!NS_tstricmp(paths[i], path))
            {
                return true;
            }
        }
        return false;
    }
};

// Copy all of the files and subdirectories under path to a new directory named dest.
// The path names in the skiplist will be skipped and will not be copied.
template <unsigned N>
static int ensure_copy_recursive(const NS_tchar *path, const NS_tchar *dest,
                                 copy_recursive_skiplist<N>& skiplist)
{
    struct NS_tstat_t sInfo;
    int rv = NS_tlstat(path, &sInfo);
    if (rv)
    {
        LOG(("ensure_copy_recursive: path doesn't exist: " LOG_S ", rv: %d, err: %d",
             path, rv, errno));
        return READ_ERROR;
    }

#ifdef UNIX
    if (S_ISLNK(sInfo.st_mode))
    {
        return ensure_copy_symlink(path, dest);
    }
#endif

    if (!S_ISDIR(sInfo.st_mode))
    {
        return ensure_copy(path, dest);
    }

    rv = NS_tmkdir(dest, sInfo.st_mode);
    if (rv < 0 && errno != EEXIST)
    {
        LOG(("ensure_copy_recursive: could not create destination directory: " LOG_S ", rv: %d, err: %d",
             path, rv, errno));
        return WRITE_ERROR;
    }

    NS_tDIR *dir;
    NS_tdirent *entry;

    dir = NS_topendir(path);
    if (!dir)
    {
        LOG(("ensure_copy_recursive: path is not a directory: " LOG_S ", rv: %d, err: %d",
             path, rv, errno));
        return READ_ERROR;
    }

    while ((entry = NS_treaddir(dir)) != 0)
    {
        if (NS_tstrcmp(entry->d_name, NS_T(".")) &&
                NS_tstrcmp(entry->d_name, NS_T("..")))
        {
            NS_tchar childPath[MAXPATHLEN];
            NS_tsnprintf(childPath, sizeof(childPath)/sizeof(childPath[0]),
                         NS_T("%s/%s"), path, entry->d_name);
            if (skiplist.find(childPath))
            {
                continue;
            }
            NS_tchar childPathDest[MAXPATHLEN];
            NS_tsnprintf(childPathDest, sizeof(childPathDest)/sizeof(childPathDest[0]),
                         NS_T("%s/%s"), dest, entry->d_name);
            rv = ensure_copy_recursive(childPath, childPathDest, skiplist);
            if (rv)
            {
                break;
            }
        }
    }
    NS_tclosedir(dir);
    return rv;
}

// Renames the specified file to the new file specified. If the destination file
// exists it is removed.
static int rename_file(const NS_tchar *spath, const NS_tchar *dpath,
                       bool allowDirs = false)
{
    int rv = ensure_parent_dir(dpath);
    if (rv)
        return rv;

    struct NS_tstat_t spathInfo;
    rv = NS_tstat(spath, &spathInfo);
    if (rv)
    {
        LOG(("rename_file: failed to read file status info: " LOG_S ", " \
             "err: %d", spath, errno));
        return READ_ERROR;
    }

    if (!S_ISREG(spathInfo.st_mode))
    {
        if (allowDirs && !S_ISDIR(spathInfo.st_mode))
        {
            LOG(("rename_file: path present, but not a file: " LOG_S ", err: %d",
                 spath, errno));
            return RENAME_ERROR_EXPECTED_FILE;
        }
        else
        {
            LOG(("rename_file: proceeding to rename the directory"));
        }
    }

    if (!NS_taccess(dpath, F_OK))
    {
        if (ensure_remove(dpath))
        {
            LOG(("rename_file: destination file exists and could not be " \
                 "removed: " LOG_S, dpath));
            return WRITE_ERROR_DELETE_FILE;
        }
    }

    if (NS_trename(spath, dpath) != 0)
    {
        LOG(("rename_file: failed to rename file - src: " LOG_S ", " \
             "dst:" LOG_S ", err: %d", spath, dpath, errno));
        return WRITE_ERROR;
    }

    return OK;
}

#ifdef _WIN32
// Remove the directory pointed to by path and all of its files and
// sub-directories. If a file is in use move it to the tobedeleted directory
// and attempt to schedule removal of the file on reboot
static int remove_recursive_on_reboot(const NS_tchar *path, const NS_tchar *deleteDir)
{
    struct NS_tstat_t sInfo;
    int rv = NS_tlstat(path, &sInfo);
    if (rv)
    {
        // This error is benign
        return rv;
    }

    if (!S_ISDIR(sInfo.st_mode))
    {
        NS_tchar tmpDeleteFile[MAXPATHLEN];
        GetTempFileNameW(deleteDir, L"rep", 0, tmpDeleteFile);
        NS_tremove(tmpDeleteFile);
        rv = rename_file(path, tmpDeleteFile, false);
        if (MoveFileEx(rv ? path : tmpDeleteFile, nullptr, MOVEFILE_DELAY_UNTIL_REBOOT))
        {
            LOG(("remove_recursive_on_reboot: file will be removed on OS reboot: "
                 LOG_S, rv ? path : tmpDeleteFile));
        }
        else
        {
            LOG(("remove_recursive_on_reboot: failed to schedule OS reboot removal of "
                 "file: " LOG_S, rv ? path : tmpDeleteFile));
        }
        return rv;
    }

    NS_tDIR *dir;
    NS_tdirent *entry;

    dir = NS_topendir(path);
    if (!dir)
    {
        LOG(("remove_recursive_on_reboot: unable to open directory: " LOG_S
             ", rv: %d, err: %d",
             path, rv, errno));
        return rv;
    }

    while ((entry = NS_treaddir(dir)) != 0)
    {
        if (NS_tstrcmp(entry->d_name, NS_T(".")) &&
                NS_tstrcmp(entry->d_name, NS_T("..")))
        {
            NS_tchar childPath[MAXPATHLEN];
            NS_tsnprintf(childPath, sizeof(childPath)/sizeof(childPath[0]),
                         NS_T("%s/%s"), path, entry->d_name);
            // There is no need to check the return value of this call since this
            // function is only called after an update is successful and there is not
            // much that can be done to recover if it isn't successful. There is also
            // no need to log the value since it will have already been logged.
            remove_recursive_on_reboot(childPath, deleteDir);
        }
    }

    NS_tclosedir(dir);

    if (rv == OK)
    {
        ensure_write_permissions(path);
        rv = NS_trmdir(path);
        if (rv)
        {
            LOG(("remove_recursive_on_reboot: unable to remove directory: " LOG_S
                 ", rv: %d, err: %d", path, rv, errno));
        }
    }
    return rv;
}
#endif

//-----------------------------------------------------------------------------

// Create a backup of the specified file by renaming it.
static int backup_create(const NS_tchar *path)
{
    NS_tchar backup[MAXPATHLEN];
    NS_tsnprintf(backup, sizeof(backup)/sizeof(backup[0]),
                 NS_T("%s") BACKUP_EXT, path);

    return rename_file(path, backup);
}

// Rename the backup of the specified file that was created by renaming it back
// to the original file.
static int backup_restore(const NS_tchar *path, const NS_tchar *relPath)
{
    NS_tchar backup[MAXPATHLEN];
    NS_tsnprintf(backup, sizeof(backup)/sizeof(backup[0]),
                 NS_T("%s") BACKUP_EXT, path);

    NS_tchar relBackup[MAXPATHLEN];
    NS_tsnprintf(relBackup, sizeof(relBackup) / sizeof(relBackup[0]),
                 NS_T("%s") BACKUP_EXT, relPath);

    if (NS_taccess(backup, F_OK))
    {
        LOG(("backup_restore: backup file doesn't exist: " LOG_S, relBackup));
        return OK;
    }

    return rename_file(backup, path);
}

// Discard the backup of the specified file that was created by renaming it.
static int backup_discard(const NS_tchar *path, const NS_tchar *relPath)
{
    NS_tchar backup[MAXPATHLEN];
    NS_tsnprintf(backup, sizeof(backup)/sizeof(backup[0]),
                 NS_T("%s") BACKUP_EXT, path);

    NS_tchar relBackup[MAXPATHLEN];
    NS_tsnprintf(relBackup, sizeof(relBackup) / sizeof(relBackup[0]),
                 NS_T("%s") BACKUP_EXT, relPath);

    // Nothing to discard
    if (NS_taccess(backup, F_OK))
    {
        return OK;
    }

    int rv = ensure_remove(backup);
#if defined(_WIN32)
    if (rv && !sStagedUpdate && !sReplaceRequest)
    {
        LOG(("backup_discard: unable to remove: " LOG_S, relBackup));
        NS_tchar path[MAXPATHLEN];
        GetTempFileNameW(gDeleteDirPath, L"moz", 0, path);
        if (rename_file(backup, path))
        {
            LOG(("backup_discard: failed to rename file:" LOG_S ", dst:" LOG_S,
                 relBackup, relPath));
            return WRITE_ERROR_DELETE_BACKUP;
        }
        // The MoveFileEx call to remove the file on OS reboot will fail if the
        // process doesn't have write access to the HKEY_LOCAL_MACHINE registry key
        // but this is ok since the installer / uninstaller will delete the
        // directory containing the file along with its contents after an update is
        // applied, on reinstall, and on uninstall.
        if (MoveFileEx(path, nullptr, MOVEFILE_DELAY_UNTIL_REBOOT))
        {
            LOG(("backup_discard: file renamed and will be removed on OS " \
                 "reboot: " LOG_S, relPath));
        }
        else
        {
            LOG(("backup_discard: failed to schedule OS reboot removal of " \
                 "file: " LOG_S, relPath));
        }
    }
#else
    if (rv)
        return WRITE_ERROR_DELETE_BACKUP;
#endif

    return OK;
}

// Helper function for post-processing a temporary backup.
static void backup_finish(const NS_tchar *path, const NS_tchar *relPath,
                          int status)
{
    if (status == OK)
        backup_discard(path, relPath);
    else
        backup_restore(path, relPath);
}

//-----------------------------------------------------------------------------

static int DoUpdate(ArchiveReader& ArchiveReader);

class Action
{
public:
    Action() : mProgressCost(1), mNext(nullptr) { }
    virtual ~Action() { }

    virtual int Parse(NS_tchar *line) = 0;

    // Do any preprocessing to ensure that the action can be performed.  Execute
    // will be called if this Action and all others return OK from this method.
    virtual int Prepare() = 0;

    // Perform the operation.  Return OK to indicate success.  After all actions
    // have been executed, Finish will be called.  A requirement of Execute is
    // that its operation be reversible from Finish.
    virtual int Execute() = 0;

    // Finish is called after execution of all actions.  If status is OK, then
    // all actions were successfully executed.  Otherwise, some action failed.
    virtual void Finish(int status) = 0;

    int mProgressCost;
private:
    Action* mNext;

    friend class ActionList;
};

class RemoveFile : public Action
{
public:
    RemoveFile() : mSkip(0) { }

    int Parse(NS_tchar *line);
    int Prepare();
    int Execute();
    void Finish(int status);

private:
    std::unique_ptr<const NS_tchar[]> mFile;
    std::unique_ptr<NS_tchar[]> mRelPath;
    int mSkip;
};

int
RemoveFile::Parse(NS_tchar *line)
{
    // format "<deadfile>"

    NS_tchar* validPath = get_valid_path(&line);
    if (!validPath)
        return PARSE_ERROR;

    mRelPath.reset(new NS_tchar[MAXPATHLEN]);
    NS_tstrcpy(mRelPath.get(), validPath);

    mFile.reset(new_absolute_path(validPath));
    if (!mFile)
    {
        return PARSE_ERROR;
    }

    return OK;
}

int
RemoveFile::Prepare()
{
    // Skip the file if it already doesn't exist.
    int rv = NS_taccess(mFile.get(), F_OK);
    if (rv)
    {
        mSkip = 1;
        mProgressCost = 0;
        return OK;
    }

    LOG(("PREPARE REMOVEFILE " LOG_S, mRelPath.get()));

    // Make sure that we're actually a file...
    struct NS_tstat_t fileInfo;
    rv = NS_tstat(mFile.get(), &fileInfo);
    if (rv)
    {
        LOG(("failed to read file status info: " LOG_S ", err: %d", mFile.get(),
             errno));
        return READ_ERROR;
    }

    if (!S_ISREG(fileInfo.st_mode))
    {
        LOG(("path present, but not a file: " LOG_S, mFile.get()));
        return DELETE_ERROR_EXPECTED_FILE;
    }

    NS_tchar *slash = (NS_tchar *) NS_tstrrchr(mFile.get(), NS_T('/'));
    if (slash)
    {
        *slash = NS_T('\0');
        rv = NS_taccess(mFile.get(), W_OK);
        *slash = NS_T('/');
    }
    else
    {
        rv = NS_taccess(NS_T("."), W_OK);
    }

    if (rv)
    {
        LOG(("access failed: %d", errno));
        return WRITE_ERROR_FILE_ACCESS_DENIED;
    }

    return OK;
}

int
RemoveFile::Execute()
{
    if (mSkip)
        return OK;

    LOG(("EXECUTE REMOVEFILE " LOG_S, mRelPath.get()));

    // The file is checked for existence here and in Prepare since it might have
    // been removed by a separate instruction: bug 311099.
    int rv = NS_taccess(mFile.get(), F_OK);
    if (rv)
    {
        LOG(("file cannot be removed because it does not exist; skipping"));
        mSkip = 1;
        return OK;
    }

    // Rename the old file. It will be removed in Finish.
    rv = backup_create(mFile.get());
    if (rv)
    {
        LOG(("backup_create failed: %d", rv));
        return rv;
    }

    return OK;
}

void
RemoveFile::Finish(int status)
{
    if (mSkip)
        return;

    LOG(("FINISH REMOVEFILE " LOG_S, mRelPath.get()));

    backup_finish(mFile.get(), mRelPath.get(), status);
}

class RemoveDir : public Action
{
public:
    RemoveDir() : mSkip(0) { }

    virtual int Parse(NS_tchar *line);
    virtual int Prepare(); // check that the source dir exists
    virtual int Execute();
    virtual void Finish(int status);

private:
    std::unique_ptr<NS_tchar[]> mDir;
    std::unique_ptr<NS_tchar[]> mRelPath;
    int mSkip;
};

int
RemoveDir::Parse(NS_tchar *line)
{
    // format "<deaddir>/"

    NS_tchar* validPath = get_valid_path(&line, true);
    if (!validPath)
        return PARSE_ERROR;

    mRelPath.reset(new NS_tchar[MAXPATHLEN]);
    NS_tstrcpy(mRelPath.get(), validPath);

    mDir.reset(new_absolute_path(validPath));
    if (!mDir)
    {
        return PARSE_ERROR;
    }

    return OK;
}

int
RemoveDir::Prepare()
{
    // We expect the directory to exist if we are to remove it.
    int rv = NS_taccess(mDir.get(), F_OK);
    if (rv)
    {
        mSkip = 1;
        mProgressCost = 0;
        return OK;
    }

    LOG(("PREPARE REMOVEDIR " LOG_S "/", mRelPath.get()));

    // Make sure that we're actually a dir.
    struct NS_tstat_t dirInfo;
    rv = NS_tstat(mDir.get(), &dirInfo);
    if (rv)
    {
        LOG(("failed to read directory status info: " LOG_S ", err: %d", mRelPath.get(),
             errno));
        return READ_ERROR;
    }

    if (!S_ISDIR(dirInfo.st_mode))
    {
        LOG(("path present, but not a directory: " LOG_S, mRelPath.get()));
        return DELETE_ERROR_EXPECTED_DIR;
    }

    rv = NS_taccess(mDir.get(), W_OK);
    if (rv)
    {
        LOG(("access failed: %d, %d", rv, errno));
        return WRITE_ERROR_DIR_ACCESS_DENIED;
    }

    return OK;
}

int
RemoveDir::Execute()
{
    if (mSkip)
        return OK;

    LOG(("EXECUTE REMOVEDIR " LOG_S "/", mRelPath.get()));

    // The directory is checked for existence at every step since it might have
    // been removed by a separate instruction: bug 311099.
    int rv = NS_taccess(mDir.get(), F_OK);
    if (rv)
    {
        LOG(("directory no longer exists; skipping"));
        mSkip = 1;
    }

    return OK;
}

void
RemoveDir::Finish(int status)
{
    if (mSkip || status != OK)
        return;

    LOG(("FINISH REMOVEDIR " LOG_S "/", mRelPath.get()));

    // The directory is checked for existence at every step since it might have
    // been removed by a separate instruction: bug 311099.
    int rv = NS_taccess(mDir.get(), F_OK);
    if (rv)
    {
        LOG(("directory no longer exists; skipping"));
        return;
    }


    if (status == OK)
    {
        if (NS_trmdir(mDir.get()))
        {
            LOG(("non-fatal error removing directory: " LOG_S "/, rv: %d, err: %d",
                 mRelPath.get(), rv, errno));
        }
    }
}

class AddFile : public Action
{
public:
    AddFile(ArchiveReader& ar) : mAdded(false), mArchiveReader(ar) { }

    virtual int Parse(NS_tchar *line);
    virtual int Prepare();
    virtual int Execute();
    virtual void Finish(int status);

private:
    std::unique_ptr<NS_tchar[]> mFile;
    std::unique_ptr<NS_tchar[]> mRelPath;
    bool mAdded;
    ArchiveReader& mArchiveReader;
};

int
AddFile::Parse(NS_tchar *line)
{
    // format "<newfile>"

    NS_tchar* validPath = get_valid_path(&line);
    if (!validPath)
        return PARSE_ERROR;

    mRelPath.reset(new NS_tchar[MAXPATHLEN]);
    NS_tstrcpy(mRelPath.get(), validPath);

    mFile.reset(new_absolute_path(validPath));
    if (!mFile)
    {
        return PARSE_ERROR;
    }

    return OK;
}

int
AddFile::Prepare()
{
    LOG(("PREPARE ADD " LOG_S, mRelPath.get()));

    return OK;
}

int
AddFile::Execute()
{
    LOG(("EXECUTE ADD " LOG_S, mRelPath.get()));

    int rv;

    // First make sure that we can actually get rid of any existing file.
    rv = NS_taccess(mFile.get(), F_OK);
    if (rv == 0)
    {
        rv = backup_create(mFile.get());
        if (rv)
            return rv;
    }
    else
    {
        rv = ensure_parent_dir(mFile.get());
        if (rv)
            return rv;
    }

#ifdef _WIN32
    char sourcefile[MAXPATHLEN];
    if (!WideCharToMultiByte(CP_UTF8, 0, mRelPath.get(), -1, sourcefile,
                             MAXPATHLEN, nullptr, nullptr))
    {
        LOG(("error converting wchar to utf8: %d", GetLastError()));
        return STRING_CONVERSION_ERROR;
    }

    rv = mArchiveReader.ExtractFile(sourcefile, mFile.get());
#else
    rv = mArchiveReader.ExtractFile(mRelPath.get(), mFile.get());
#endif
    if (!rv)
    {
        mAdded = true;
    }
    return rv;
}

void
AddFile::Finish(int status)
{
    LOG(("FINISH ADD " LOG_S, mRelPath.get()));
    // When there is an update failure and a file has been added it is removed
    // here since there might not be a backup to replace it.
    if (status && mAdded)
        NS_tremove(mFile.get());
    backup_finish(mFile.get(), mRelPath.get(), status);
}

class PatchFile : public Action
{
public:
    PatchFile(ArchiveReader& ar) : mPatchFile(nullptr), mPatchIndex(-1), buf(nullptr), mArchiveReader(ar) { }

    virtual ~PatchFile();

    virtual int Parse(NS_tchar *line);
    virtual int Prepare(); // should check for patch file and for checksum here
    virtual int Execute();
    virtual void Finish(int status);

private:
    int LoadSourceFile(FILE* ofile);

    static int sPatchIndex;

    const NS_tchar *mPatchFile;
    std::unique_ptr<NS_tchar> mFile;
    std::unique_ptr<NS_tchar> mFileRelPath;
    int mPatchIndex;
    MBSPatchHeader header;
    unsigned char *buf;
    NS_tchar spath[MAXPATHLEN];
    AutoFile mPatchStream;
    ArchiveReader& mArchiveReader;
};

int PatchFile::sPatchIndex = 0;

PatchFile::~PatchFile()
{
    // Make sure mPatchStream gets unlocked on Windows; the system will do that,
    // but not until some indeterminate future time, and we want determinism.
    // Normally this happens at the end of Execute, when we close the stream;
    // this call is here in case Execute errors out.
#ifdef _WIN32
    if (mPatchStream)
    {
        UnlockFile((HANDLE)_get_osfhandle(fileno(mPatchStream)), (DWORD)0, (DWORD)0, (DWORD)-1, (DWORD)-1);
    }
#endif

    // delete the temporary patch file
    if (spath[0])
        NS_tremove(spath);

    if (buf)
        free(buf);
}

int
PatchFile::LoadSourceFile(FILE* ofile)
{
    struct stat os;
    int rv = fstat(fileno((FILE *)ofile), &os);
    if (rv)
    {
        LOG(("LoadSourceFile: unable to stat destination file: " LOG_S ", " \
             "err: %d", mFileRelPath.get(), errno));
        return READ_ERROR;
    }

    if (uint32_t(os.st_size) != header.slen)
    {
        LOG(("LoadSourceFile: destination file size %d does not match expected size %d",
             uint32_t(os.st_size), header.slen));
        return LOADSOURCE_ERROR_WRONG_SIZE;
    }

    buf = (unsigned char *) malloc(header.slen);
    if (!buf)
        return UPDATER_MEM_ERROR;

    size_t r = header.slen;
    unsigned char *rb = buf;
    while (r)
    {
        const size_t count = std::min<size_t>(SSIZE_MAX, r);
        size_t c = fread(rb, 1, count, ofile);
        if (c != count)
        {
            LOG(("LoadSourceFile: error reading destination file: " LOG_S,
                 mFileRelPath.get()));
            return READ_ERROR;
        }

        r -= c;
        rb += c;
    }

    // Verify that the contents of the source file correspond to what we expect.

    unsigned int crc = crc32(buf, header.slen);

    if (crc != header.scrc32)
    {
        LOG(("LoadSourceFile: destination file crc %d does not match expected " \
             "crc %d", crc, header.scrc32));
        return CRC_ERROR;
    }

    return OK;
}

int
PatchFile::Parse(NS_tchar *line)
{
    // format "<patchfile>" "<filetopatch>"

    // Get the path to the patch file inside of the mar
    mPatchFile = mstrtok(kQuote, &line);
    if (!mPatchFile)
        return PARSE_ERROR;

    // consume whitespace between args
    NS_tchar *q = mstrtok(kQuote, &line);
    if (!q)
        return PARSE_ERROR;

    NS_tchar* validPath = get_valid_path(&line);
    if (!validPath)
        return PARSE_ERROR;
    mFileRelPath.reset(new NS_tchar[MAXPATHLEN]);
    NS_tstrcpy(mFileRelPath.get(), validPath);

    mFile.reset(new_absolute_path(validPath));
    if (!mFile)
    {
        return PARSE_ERROR;
    }

    return OK;
}

int
PatchFile::Prepare()
{
    LOG(("PREPARE PATCH " LOG_S, mFileRelPath.get()));

    // extract the patch to a temporary file
    mPatchIndex = sPatchIndex++;

    int nWrittenBytes = NS_tsnprintf(spath, sizeof(spath)/sizeof(spath[0]),
                 NS_T("%s/updating/%d.patch"), gWorkingDirPath, mPatchIndex);
    (void) nWrittenBytes;

    NS_tremove(spath);

    mPatchStream = NS_tfopen(spath, NS_T("wb+"));
    if (!mPatchStream)
        return WRITE_ERROR;

#ifdef _WIN32
    // Lock the patch file, so it can't be messed with between
    // when we're done creating it and when we go to apply it.
    if (!LockFile((HANDLE)_get_osfhandle(fileno(mPatchStream)), (DWORD)0, (DWORD)0, (DWORD)-1, (DWORD)-1))
    {
        LOG(("Couldn't lock patch file: %d", GetLastError()));
        // TODO: moggi: fix the build problem with LOCK_ERROR_PATCH_FILE
        return WRITE_ERROR; //return LOCK_ERROR_PATCH_FILE;
    }
    char sourcefile[MAXPATHLEN];
    if (!WideCharToMultiByte(CP_UTF8, 0, mPatchFile, -1, sourcefile, MAXPATHLEN,
                             nullptr, nullptr))
    {
        LOG(("error converting wchar to utf8: %d", GetLastError()));
        return STRING_CONVERSION_ERROR;
    }

    int rv = mArchiveReader.ExtractFileToStream(sourcefile, mPatchStream);
#else
    int rv = mArchiveReader.ExtractFileToStream(mPatchFile, mPatchStream);
#endif

    return rv;
}

int
PatchFile::Execute()
{
    LOG(("EXECUTE PATCH " LOG_S, mFileRelPath.get()));

    fseek(mPatchStream, 0, SEEK_SET);

    int rv = MBS_ReadHeader(mPatchStream, &header);
    if (rv)
        return rv;

    FILE *origfile = nullptr;
#ifdef _WIN32
    if (NS_tstrcmp(mFileRelPath.get(), gCallbackRelPath) == 0)
    {
        // Read from the copy of the callback when patching since the callback can't
        // be opened for reading to prevent the application from being launched.
        origfile = NS_tfopen(gCallbackBackupPath, NS_T("rb"));
    }
    else
    {
        origfile = NS_tfopen(mFile.get(), NS_T("rb"));
    }
#else
    origfile = NS_tfopen(mFile.get(), NS_T("rb"));
#endif

    if (!origfile)
    {
        LOG(("unable to open destination file: " LOG_S ", err: %d",
             mFileRelPath.get(), errno));
        return READ_ERROR;
    }

    rv = LoadSourceFile(origfile);
    fclose(origfile);
    if (rv)
    {
        LOG(("LoadSourceFile failed"));
        return rv;
    }

    // Rename the destination file if it exists before proceeding so it can be
    // used to restore the file to its original state if there is an error.
    struct NS_tstat_t ss;
    rv = NS_tstat(mFile.get(), &ss);
    if (rv)
    {
        LOG(("failed to read file status info: " LOG_S ", err: %d",
             mFileRelPath.get(), errno));
        return READ_ERROR;
    }

    rv = backup_create(mFile.get());
    if (rv)
        return rv;

#if defined(HAVE_POSIX_FALLOCATE)
    AutoFile ofile(ensure_open(mFile.get(), NS_T("wb+"), ss.st_mode));
    posix_fallocate(fileno((FILE *)ofile), 0, header.dlen);
#elif defined(_WIN32)
    bool shouldTruncate = true;
    // Creating the file, setting the size, and then closing the file handle
    // lessens fragmentation more than any other method tested. Other methods that
    // have been tested are:
    // 1. _chsize / _chsize_s reduced fragmentation though not completely.
    // 2. _get_osfhandle and then setting the size reduced fragmentation though
    //    not completely. There are also reports of _get_osfhandle failing on
    //    mingw.
    HANDLE hfile = CreateFileW(mFile.get(),
                               GENERIC_WRITE,
                               0,
                               nullptr,
                               CREATE_ALWAYS,
                               FILE_ATTRIBUTE_NORMAL,
                               nullptr);

    if (hfile != INVALID_HANDLE_VALUE)
    {
        if (SetFilePointer(hfile, header.dlen,
                           nullptr, FILE_BEGIN) != INVALID_SET_FILE_POINTER &&
                SetEndOfFile(hfile) != 0)
        {
            shouldTruncate = false;
        }
        CloseHandle(hfile);
    }

    AutoFile ofile(ensure_open(mFile.get(), shouldTruncate ? NS_T("wb+") : NS_T("rb+"),
                               ss.st_mode));
#elif defined(MACOSX)
    AutoFile ofile(ensure_open(mFile.get(), NS_T("wb+"), ss.st_mode));
    // Modified code from FileUtils.cpp
    fstore_t store = {F_ALLOCATECONTIG, F_PEOFPOSMODE, 0, header.dlen};
    // Try to get a continuous chunk of disk space
    rv = fcntl(fileno((FILE *)ofile), F_PREALLOCATE, &store);
    if (rv == -1)
    {
        // OK, perhaps we are too fragmented, allocate non-continuous
        store.fst_flags = F_ALLOCATEALL;
        rv = fcntl(fileno((FILE *)ofile), F_PREALLOCATE, &store);
    }

    if (rv != -1)
    {
        ftruncate(fileno((FILE *)ofile), header.dlen);
    }
#else
    AutoFile ofile(ensure_open(mFile.get(), NS_T("wb+"), ss.st_mode));
#endif

    if (ofile == nullptr)
    {
        LOG(("unable to create new file: " LOG_S ", err: %d", mFileRelPath.get(),
             errno));
        return WRITE_ERROR_OPEN_PATCH_FILE;
    }

#ifdef _WIN32
    if (!shouldTruncate)
    {
        fseek(ofile, 0, SEEK_SET);
    }
#endif

    rv = MBS_ApplyPatch(&header, mPatchStream, buf, ofile);

    // Go ahead and do a bit of cleanup now to minimize runtime overhead.
    // Make sure mPatchStream gets unlocked on Windows; the system will do that,
    // but not until some indeterminate future time, and we want determinism.
#ifdef _WIN32
    UnlockFile((HANDLE)_get_osfhandle(fileno(mPatchStream)), (DWORD)0, (DWORD)0, (DWORD)-1, (DWORD)-1);
#endif
    // Set mPatchStream to nullptr to make AutoFile close the file,
    // so it can be deleted on Windows.
    mPatchStream = nullptr;
    NS_tremove(spath);
    spath[0] = NS_T('\0');
    free(buf);
    buf = nullptr;
    return rv;
}

void
PatchFile::Finish(int status)
{
    LOG(("FINISH PATCH " LOG_S, mFileRelPath.get()));

    backup_finish(mFile.get(), mFileRelPath.get(), status);
}

class AddIfFile : public AddFile
{
public:
    AddIfFile(ArchiveReader& archiveReader);

    virtual int Parse(NS_tchar *line);
    virtual int Prepare();
    virtual int Execute();
    virtual void Finish(int status);

protected:
    std::unique_ptr<NS_tchar[]> mTestFile;
};

AddIfFile::AddIfFile(ArchiveReader& archiveReader):
    AddFile(archiveReader)
{
}

int
AddIfFile::Parse(NS_tchar *line)
{
    // format "<testfile>" "<newfile>"

    mTestFile.reset(new_absolute_path(get_valid_path(&line)));
    if (!mTestFile)
        return PARSE_ERROR;

    // consume whitespace between args
    NS_tchar *q = mstrtok(kQuote, &line);
    if (!q)
        return PARSE_ERROR;

    return AddFile::Parse(line);
}

int
AddIfFile::Prepare()
{
    // If the test file does not exist, then skip this action.
    if (NS_taccess(mTestFile.get(), F_OK))
    {
        mTestFile = nullptr;
        return OK;
    }

    return AddFile::Prepare();
}

int
AddIfFile::Execute()
{
    if (!mTestFile)
        return OK;

    return AddFile::Execute();
}

void
AddIfFile::Finish(int status)
{
    if (!mTestFile)
        return;

    AddFile::Finish(status);
}

class AddIfNotFile : public AddFile
{
public:
    AddIfNotFile(ArchiveReader& archiveReader);

    virtual int Parse(NS_tchar *line);
    virtual int Prepare();
    virtual int Execute();
    virtual void Finish(int status);

protected:
    std::unique_ptr<NS_tchar[]> mTestFile;
};

AddIfNotFile::AddIfNotFile(ArchiveReader& archiveReader):
    AddFile(archiveReader)
{
}

int
AddIfNotFile::Parse(NS_tchar *line)
{
    // format "<testfile>" "<newfile>"

    mTestFile.reset(new_absolute_path(get_valid_path(&line)));
    if (!mTestFile)
        return PARSE_ERROR;

    // consume whitespace between args
    NS_tchar *q = mstrtok(kQuote, &line);
    if (!q)
        return PARSE_ERROR;

    return AddFile::Parse(line);
}

int
AddIfNotFile::Prepare()
{
    // If the test file exists, then skip this action.
    if (!NS_taccess(mTestFile.get(), F_OK))
    {
        mTestFile = NULL;
        return OK;
    }

    return AddFile::Prepare();
}

int
AddIfNotFile::Execute()
{
    if (!mTestFile)
        return OK;

    return AddFile::Execute();
}

void
AddIfNotFile::Finish(int status)
{
    if (!mTestFile)
        return;

    AddFile::Finish(status);
}

class PatchIfFile : public PatchFile
{
public:
    PatchIfFile(ArchiveReader& archiveReader);

    virtual int Parse(NS_tchar *line);
    virtual int Prepare(); // should check for patch file and for checksum here
    virtual int Execute();
    virtual void Finish(int status);

private:
    std::unique_ptr<NS_tchar[]> mTestFile;
};

PatchIfFile::PatchIfFile(ArchiveReader& archiveReader):
    PatchFile(archiveReader)
{
}

int
PatchIfFile::Parse(NS_tchar *line)
{
    // format "<testfile>" "<patchfile>" "<filetopatch>"

    mTestFile.reset(new_absolute_path(get_valid_path(&line)));
    if (!mTestFile)
        return PARSE_ERROR;

    // consume whitespace between args
    NS_tchar *q = mstrtok(kQuote, &line);
    if (!q)
        return PARSE_ERROR;

    return PatchFile::Parse(line);
}

int
PatchIfFile::Prepare()
{
    // If the test file does not exist, then skip this action.
    if (NS_taccess(mTestFile.get(), F_OK))
    {
        mTestFile = nullptr;
        return OK;
    }

    return PatchFile::Prepare();
}

int
PatchIfFile::Execute()
{
    if (!mTestFile)
        return OK;

    return PatchFile::Execute();
}

void
PatchIfFile::Finish(int status)
{
    if (!mTestFile)
        return;

    PatchFile::Finish(status);
}

//-----------------------------------------------------------------------------

#ifdef _WIN32

/**
 * Launch the post update application (helper.exe). It takes in the path of the
 * callback application to calculate the path of helper.exe. For service updates
 * this is called from both the system account and the current user account.
 *
 * @param  installationDir The path to the callback application binary.
 * @param  updateInfoDir   The directory where update info is stored.
 * @return true if there was no error starting the process.
 */
bool
LaunchWinPostProcess(const WCHAR *installationDir,
                     const WCHAR *updateInfoDir)
{
    WCHAR workingDirectory[MAX_PATH + 1] = { L'\0' };
    wcsncpy(workingDirectory, installationDir, MAX_PATH);

    // TODO: moggi: needs adaptation for LibreOffice
    // Most likely we don't have the helper method yet. Check if we really need it.

    // Launch helper.exe to perform post processing (e.g. registry and log file
    // modifications) for the update.
    WCHAR inifile[MAX_PATH + 1] = { L'\0' };
    wcsncpy(inifile, installationDir, MAX_PATH);
    if (!PathAppendSafe(inifile, L"updater.ini"))
    {
        return false;
    }

    WCHAR exefile[MAX_PATH + 1];
    WCHAR exearg[MAX_PATH + 1];
    WCHAR exeasync[10];
    bool async = true;
    if (!GetPrivateProfileStringW(L"PostUpdateWin", L"ExeRelPath", nullptr,
                                  exefile, MAX_PATH + 1, inifile))
    {
        return false;
    }

    if (!GetPrivateProfileStringW(L"PostUpdateWin", L"ExeArg", nullptr, exearg,
                                  MAX_PATH + 1, inifile))
    {
        return false;
    }

    if (!GetPrivateProfileStringW(L"PostUpdateWin", L"ExeAsync", L"TRUE",
                                  exeasync,
                                  sizeof(exeasync)/sizeof(exeasync[0]),
                                  inifile))
    {
        return false;
    }

    // Verify that exeFile doesn't contain relative paths
    if (wcsstr(exefile, L"..") != nullptr)
    {
        return false;
    }

    WCHAR exefullpath[MAX_PATH + 1] = { L'\0' };
    wcsncpy(exefullpath, installationDir, MAX_PATH);
    if (!PathAppendSafe(exefullpath, exefile))
    {
        return false;
    }

#if !defined(TEST_UPDATER) && defined(MAINTENANCE_SERVICE)
    if (sUsingService &&
            !DoesBinaryMatchAllowedCertificates(installationDir, exefullpath))
    {
        return false;
    }
#endif

    WCHAR dlogFile[MAX_PATH + 1];
    if (!PathGetSiblingFilePath(dlogFile, exefullpath, L"uninstall.update"))
    {
        return false;
    }

    WCHAR slogFile[MAX_PATH + 1] = { L'\0' };
    wcsncpy(slogFile, updateInfoDir, MAX_PATH);
    if (!PathAppendSafe(slogFile, L"update.log"))
    {
        return false;
    }

    WCHAR dummyArg[14] = { L'\0' };
    wcsncpy(dummyArg, L"argv0ignored ", sizeof(dummyArg) / sizeof(dummyArg[0]) - 1);

    size_t len = wcslen(exearg) + wcslen(dummyArg);
    WCHAR *cmdline = (WCHAR *) malloc((len + 1) * sizeof(WCHAR));
    if (!cmdline)
    {
        return false;
    }

    wcsncpy(cmdline, dummyArg, len);
    wcscat(cmdline, exearg);

    if (sUsingService ||
            !_wcsnicmp(exeasync, L"false", 6) ||
            !_wcsnicmp(exeasync, L"0", 2))
    {
        async = false;
    }

    // We want to launch the post update helper app to update the Windows
    // registry even if there is a failure with removing the uninstall.update
    // file or copying the update.log file.
    CopyFileW(slogFile, dlogFile, false);

    STARTUPINFOW si = {sizeof(si), 0};
    si.lpDesktop = L"";
    PROCESS_INFORMATION pi = {0};

    bool ok = CreateProcessW(exefullpath,
                             cmdline,
                             nullptr,  // no special security attributes
                             nullptr,  // no special thread attributes
                             false,    // don't inherit filehandles
                             0,        // No special process creation flags
                             nullptr,  // inherit my environment
                             workingDirectory,
                             &si,
                             &pi);
    free(cmdline);
    if (ok)
    {
        if (!async)
        {
            WaitForSingleObject(pi.hProcess, INFINITE);
        }
        CloseHandle(pi.hProcess);
        CloseHandle(pi.hThread);
    }
    return ok;
}

#endif

static void
LaunchCallbackApp(const NS_tchar *workingDir,
                  int argc,
                  NS_tchar **argv,
                  bool usingService)
{
    putenv(const_cast<char*>("NO_EM_RESTART="));
    putenv(const_cast<char*>("MOZ_LAUNCHED_CHILD=1"));

    // Run from the specified working directory (see bug 312360). This is not
    // necessary on Windows CE since the application that launches the updater
    // passes the working directory as an --environ: command line argument.
    if (NS_tchdir(workingDir) != 0)
    {
        LOG(("Warning: chdir failed"));
    }

#if defined(USE_EXECV)
    (void) argc;
    (void) usingService; // avoid warnings
    execv(argv[0], argv);
#elif defined(MACOSX)
    LaunchChild(argc, (const char**)argv);
#elif defined(_WIN32)
    // Do not allow the callback to run when running an update through the
    // service as session 0.  The unelevated updater.exe will do the launching.
    if (!usingService)
    {
        WinLaunchChild(argv[0], argc, argv, nullptr);
    }
#else
# warning "Need implementation of LaunchCallbackApp"
#endif
}

static bool
WriteStatusFile(const char* aStatus)
{
    NS_tchar filename[MAXPATHLEN] = {NS_T('\0')};
#if defined(_WIN32)
    // The temp file is not removed on failure since there is client code that
    // will remove it.
    GetTempFileNameW(gPatchDirPath, L"sta", 0, filename);
#else
    NS_tsnprintf(filename, sizeof(filename)/sizeof(filename[0]),
                 NS_T("%s/update.status"), gPatchDirPath);
#endif

    // Make sure that the directory for the update status file exists
    if (ensure_parent_dir(filename))
        return false;

    // This is scoped to make the AutoFile close the file so it is possible to
    // move the temp file to the update.status file on Windows.
    {
        AutoFile file(NS_tfopen(filename, NS_T("wb+")));
        if (file == nullptr)
        {
            return false;
        }

        if (fwrite(aStatus, strlen(aStatus), 1, file) != 1)
        {
            return false;
        }
    }

#if defined(_WIN32)
    NS_tchar dstfilename[MAXPATHLEN] = {NS_T('\0')};
    NS_tsnprintf(dstfilename, sizeof(dstfilename)/sizeof(dstfilename[0]),
                 NS_T("%s\\update.status"), gPatchDirPath);
    if (MoveFileExW(filename, dstfilename, MOVEFILE_REPLACE_EXISTING) == 0)
    {
        return false;
    }
#endif

    return true;
}

static void
WriteStatusFile(int status)
{
    const char *text;

    char buf[32];
    if (status == OK)
    {
        if (sStagedUpdate)
        {
            text = "applied\n";
        }
        else
        {
            text = "succeeded\n";
        }
    }
    else
    {
        snprintf(buf, sizeof(buf)/sizeof(buf[0]), "failed: %d\n", status);
        text = buf;
    }

    WriteStatusFile(text);
}

#ifdef MAINTENANCE_SERVICE
/*
 * Read the update.status file and sets isPendingService to true if
 * the status is set to pending-service.
 *
 * @param  isPendingService Out parameter for specifying if the status
 *         is set to pending-service or not.
 * @return true if the information was retrieved and it is pending
 *         or pending-service.
 */
static bool
IsUpdateStatusPendingService()
{
    NS_tchar filename[MAXPATHLEN];
    NS_tsnprintf(filename, sizeof(filename)/sizeof(filename[0]),
                 NS_T("%s/update.status"), gPatchDirPath);

    AutoFile file(NS_tfopen(filename, NS_T("rb")));
    if (file == nullptr)
        return false;

    char buf[32] = { 0 };
    fread(buf, sizeof(buf), 1, file);

    const char kPendingService[] = "pending-service";
    const char kAppliedService[] = "applied-service";

    return (strncmp(buf, kPendingService,
                    sizeof(kPendingService) - 1) == 0) ||
           (strncmp(buf, kAppliedService,
                    sizeof(kAppliedService) - 1) == 0);
}
#endif

#ifdef _WIN32
/*
 * Read the update.status file and sets isSuccess to true if
 * the status is set to succeeded.
 *
 * @param  isSucceeded Out parameter for specifying if the status
 *         is set to succeeded or not.
 * @return true if the information was retrieved and it is succeeded.
 */
static bool
IsUpdateStatusSucceeded(bool &isSucceeded)
{
    isSucceeded = false;
    NS_tchar filename[MAXPATHLEN];
    NS_tsnprintf(filename, sizeof(filename)/sizeof(filename[0]),
                 NS_T("%s/update.status"), gPatchDirPath);

    AutoFile file(NS_tfopen(filename, NS_T("rb")));
    if (file == nullptr)
        return false;

    char buf[32] = { 0 };
    fread(buf, sizeof(buf), 1, file);

    const char kSucceeded[] = "succeeded";
    isSucceeded = strncmp(buf, kSucceeded,
                          sizeof(kSucceeded) - 1) == 0;
    return true;
}
#endif

/*
 * Copy the entire contents of the application installation directory to the
 * destination directory for the update process.
 *
 * @return 0 if successful, an error code otherwise.
 */
static int
CopyInstallDirToDestDir()
{
    // These files should not be copied over to the updated app
#ifdef _WIN32
#define SKIPLIST_COUNT 4
#elif defined(MACOSX)
#define SKIPLIST_COUNT 1
#else
#define SKIPLIST_COUNT 3
#endif
    copy_recursive_skiplist<SKIPLIST_COUNT> skiplist;

    std::unique_ptr<NS_tchar[]> pUserProfile(new NS_tchar[MAXPATHLEN]);
    NS_tstrcpy(pUserProfile.get(), gPatchDirPath);
    NS_tchar *slash = (NS_tchar *) NS_tstrrchr(pUserProfile.get(), NS_T('/'));
    if (slash)
        *slash = NS_T('\0');

    LOG(("ignore user profile directory during copy: " LOG_S, pUserProfile.get()));

    skiplist.append(0, pUserProfile.get());
#ifndef MACOSX
    skiplist.append(1, gInstallDirPath, NS_T("updated"));
    skiplist.append(2, gInstallDirPath, NS_T("updates/0"));
#ifdef _WIN32
    skiplist.append(4, gInstallDirPath, NS_T("updated.update_in_progress.lock"));
#endif
#endif

    return ensure_copy_recursive(gInstallDirPath, gWorkingDirPath, skiplist);
}

/*
 * Replace the application installation directory with the destination
 * directory in order to finish a staged update task
 *
 * @return 0 if successful, an error code otherwise.
 */
static int
ProcessReplaceRequest()
{
    // TODO: moggi: handle the user profile in the installation dir also
    // during the replacement request
    // The replacement algorithm is like this:
    // 1. Move destDir to tmpDir.  In case of failure, abort.
    // 2. Move newDir to destDir.  In case of failure, revert step 1 and abort.
    // 3. Delete tmpDir (or defer it to the next reboot).

#ifdef MACOSX
    NS_tchar destDir[MAXPATHLEN];
    NS_tsnprintf(destDir, sizeof(destDir)/sizeof(destDir[0]),
                 NS_T("%s/Contents"), gInstallDirPath);
#elif defined(_WIN32)
    // Windows preserves the case of the file/directory names.  We use the
    // GetLongPathName API in order to get the correct case for the directory
    // name, so that if the user has used a different case when launching the
    // application, the installation directory's name does not change.
    NS_tchar destDir[MAXPATHLEN];
    if (!GetLongPathNameW(gInstallDirPath, destDir,
                          sizeof(destDir)/sizeof(destDir[0])))
    {
        return NO_INSTALLDIR_ERROR;
    }
#else
    NS_tchar* destDir = gInstallDirPath;
#endif

    NS_tchar tmpDir[MAXPATHLEN];
    NS_tsnprintf(tmpDir, sizeof(tmpDir)/sizeof(tmpDir[0]),
                 NS_T("%s.bak"), destDir);

    // First try to remove the possibly existing temp directory, because if this
    // directory exists, we will fail to rename destDir.
    // No need to error check here because if this fails, we will fail in the
    // next step anyways.
    ensure_remove_recursive(tmpDir);

    LOG(("Begin moving destDir (" LOG_S ") to tmpDir (" LOG_S ")",
         destDir, tmpDir));
    LogFlush();
    int rv = rename_file(destDir, tmpDir, true);
#ifdef _WIN32
    // On Windows, if Firefox is launched using the shortcut, it will hold a handle
    // to its installation directory open, which might not get released in time.
    // Therefore we wait a little bit here to see if the handle is released.
    // If it's not released, we just fail to perform the replace request.
    const int max_retries = 10;
    int retries = 0;
    while (rv == WRITE_ERROR && (retries++ < max_retries))
    {
        LOG(("PerformReplaceRequest: destDir rename attempt %d failed. " \
             "File: " LOG_S ". Last error: %d, err: %d", retries,
             destDir, GetLastError(), rv));

        Sleep(100);

        rv = rename_file(destDir, tmpDir, true);
    }
#endif
    if (rv)
    {
        // The status file will have 'pending' written to it so there is no value in
        // returning an error specific for this failure.
        LOG(("Moving destDir to tmpDir failed, err: %d", rv));
        return rv;
    }

    NS_tchar newDir[MAXPATHLEN];
    if (is_userprofile_in_instdir())
    {
        LOG(("user profile in instdir"));
        NS_tstrcpy(newDir, tmpDir);
        NS_tstrcat(newDir, gWorkingDirPath + NS_tstrlen(gInstallDirPath));
        LOG((LOG_S, newDir));
    }
    else
    {
        NS_tsnprintf(newDir, sizeof(newDir)/sizeof(newDir[0]),
                NS_T("%s"),
                gWorkingDirPath);
    }

    LOG(("Begin moving newDir (" LOG_S ") to destDir (" LOG_S ")",
         newDir, destDir));
    rv = rename_file(newDir, destDir, true);
#ifdef MACOSX
    if (rv)
    {
        LOG(("Moving failed. Begin copying newDir (" LOG_S ") to destDir (" LOG_S ")",
             newDir, destDir));
        copy_recursive_skiplist<0> skiplist;
        rv = ensure_copy_recursive(newDir, destDir, skiplist);
    }
#endif
    if (rv)
    {
        LOG(("Moving newDir to destDir failed, err: %d", rv));
        LOG(("Now, try to move tmpDir back to destDir"));
        ensure_remove_recursive(destDir);
        int rv2 = rename_file(tmpDir, destDir, true);
        if (rv2)
        {
            LOG(("Moving tmpDir back to destDir failed, err: %d", rv2));
        }
        // The status file will be have 'pending' written to it so there is no value
        // in returning an error specific for this failure.
        return rv;
    }

    if (is_userprofile_in_instdir())
    {
        // 1.) calculate path of the user profile in the backup directory
        // 2.) move the user profile from the backup to the install directory
        NS_tchar backup_user_profile[MAXPATHLEN];
        NS_tchar userprofile[MAXPATHLEN];

        NS_tstrcpy(userprofile, gPatchDirPath);
        NS_tchar* slash = (NS_tchar *) NS_tstrrchr(userprofile, NS_T('/'));
        if (slash)
            *slash = NS_T('\0');
        NS_tstrcpy(backup_user_profile, tmpDir);
        size_t installdir_len = NS_tstrlen(destDir);

        NS_tstrcat(backup_user_profile, userprofile + installdir_len);
        LOG(("copy user profile back from " LOG_S " to " LOG_S, backup_user_profile, userprofile));
        int rv2 = rename_file(backup_user_profile, userprofile);
        if (rv2)
        {
            LOG(("failed to copy user profile back"));
        }
        if (slash)
            *slash = NS_T('/');
    }

#if !defined(_WIN32) && !defined(MACOSX)
    // Platforms that have their updates directory in the installation directory
    // need to have the last-update.log and backup-update.log files moved from the
    // old installation directory to the new installation directory.
    NS_tchar tmpLog[MAXPATHLEN];
    int nWrittenBytes = NS_tsnprintf(tmpLog, sizeof(tmpLog)/sizeof(tmpLog[0]),
                 NS_T("%s/updates/last-update.log"), tmpDir);
    (void) nWrittenBytes;
    if (!NS_taccess(tmpLog, F_OK))
    {
        NS_tchar destLog[MAXPATHLEN];
        NS_tsnprintf(destLog, sizeof(destLog)/sizeof(destLog[0]),
                     NS_T("%s/updates/last-update.log"), destDir);
        NS_tremove(destLog);
        NS_trename(tmpLog, destLog);
    }
#endif

    LOG(("Now, remove the tmpDir"));
    rv = ensure_remove_recursive(tmpDir, true);
    if (rv)
    {
        LOG(("Removing tmpDir failed, err: %d", rv));
#ifdef _WIN32
        NS_tchar deleteDir[MAXPATHLEN];
        NS_tsnprintf(deleteDir, sizeof(deleteDir)/sizeof(deleteDir[0]),
                     NS_T("%s\\%s"), destDir, DELETE_DIR);
        // Attempt to remove the tobedeleted directory and then recreate it if it
        // was successfully removed.
        _wrmdir(deleteDir);
        if (NS_taccess(deleteDir, F_OK))
        {
            NS_tmkdir(deleteDir, 0755);
        }
        remove_recursive_on_reboot(tmpDir, deleteDir);
#endif
    }

#ifdef MACOSX
    // On macOS, we need to remove the staging directory after its Contents
    // directory has been moved.
    NS_tchar updatedAppDir[MAXPATHLEN];
    NS_tsnprintf(updatedAppDir, sizeof(updatedAppDir)/sizeof(updatedAppDir[0]),
                 NS_T("%s/Updated.app"), gPatchDirPath);
    ensure_remove_recursive(updatedAppDir);
#endif

    gSucceeded = true;

    return 0;
}

#ifdef _WIN32
static void
WaitForServiceFinishThread(void* /*param*/)
{
    // We wait at most 10 minutes, we already waited 5 seconds previously
    // before deciding to show this UI.
    WaitForServiceStop(SVC_NAME, 595);
    QuitProgressUI();
}
#endif

#ifdef VERIFY_MAR_SIGNATURE
/**
 * This function reads in the ACCEPTED_MAR_CHANNEL_IDS from update-settings.ini
 *
 * @param path    The path to the ini file that is to be read
 * @param results A pointer to the location to store the read strings
 * @return OK on success
 */
static int
ReadMARChannelIDs(const NS_tchar *path, MARChannelStringTable *results)
{
    // TODO: moggi: needs adaptation for LibreOffice
    // Check where this function gets its parameters from
    const unsigned int kNumStrings = 1;
    const char *kUpdaterKeys = "ACCEPTED_MAR_CHANNEL_IDS\0";
    char updater_strings[kNumStrings][MAX_TEXT_LEN];

    int result = ReadStrings(path, kUpdaterKeys, kNumStrings,
                             updater_strings, "Settings");

    strncpy(results->MARChannelID, updater_strings[0], MAX_TEXT_LEN - 1);
    results->MARChannelID[MAX_TEXT_LEN - 1] = 0;

    return result;
}
#endif

static int
GetUpdateFileNames(std::vector<tstring>& fileNames)
{
    NS_tchar fileName[MAXPATHLEN];
    NS_tsnprintf(fileName, MAXPATHLEN,
                 NS_T("%s/update.mar"), gPatchDirPath);
    fileNames.push_back(fileName);

    // add the language packs
    NS_tDIR* dir = NS_topendir(gPatchDirPath);
    if (!dir)
    {
        LOG(("Could not open directory " LOG_S, gPatchDirPath));
        return READ_ERROR;
    }

    NS_tdirent* entry;
    while ((entry = NS_treaddir(dir)) != nullptr)
    {
        if (NS_tstrcmp(entry->d_name, NS_T(".")) &&
                NS_tstrcmp(entry->d_name, NS_T("..")) &&
                NS_tstrcmp(entry->d_name, NS_T("update.mar")))
        {
            if (NS_tstrncmp(entry->d_name, NS_T("update"), 6) == 0)
            {
                NS_tchar *dot = NS_tstrrchr(entry->d_name, NS_T('.'));
                if (dot && !NS_tstrcmp(dot, NS_T(".mar")))
                {
                    NS_tchar updatePath[MAXPATHLEN];
                    NS_tsnprintf(updatePath, sizeof(updatePath)/sizeof(updatePath[0]),
                            NS_T("%s/%s"), gPatchDirPath, entry->d_name);

                    LOG (("Found language update file: " LOG_S, updatePath));
                    fileNames.push_back(updatePath);
                }
            }
        }
    }
    return OK;
}

static int
CheckSignature(ArchiveReader& archiveReader)
{
#ifdef VERIFY_MAR_SIGNATURE
#ifdef _WIN32
    HKEY baseKey = nullptr;
    wchar_t valueName[] = L"Image Path";
    wchar_t rasenh[] = L"rsaenh.dll";
    bool reset = false;
    if (RegOpenKeyExW(HKEY_LOCAL_MACHINE,
                      L"SOFTWARE\\Microsoft\\Cryptography\\Defaults\\Provider\\Microsoft Enhanced Cryptographic Provider v1.0",
                      0, KEY_READ | KEY_WRITE,
                      &baseKey) == ERROR_SUCCESS)
    {
        wchar_t path[MAX_PATH + 1];
        DWORD size = sizeof(path);
        DWORD type;
        if (RegQueryValueExW(baseKey, valueName, 0, &type,
                             (LPBYTE)path, &size) == ERROR_SUCCESS)
        {
            if (type == REG_SZ && wcscmp(path, rasenh) == 0)
            {
                wchar_t rasenhFullPath[] = L"%SystemRoot%\\System32\\rsaenh.dll";
                if (RegSetValueExW(baseKey, valueName, 0, REG_SZ,
                                   (const BYTE*)rasenhFullPath,
                                   sizeof(rasenhFullPath)) == ERROR_SUCCESS)
                {
                    reset = true;
                }
            }
        }
    }
#endif
    int rv = archiveReader.VerifySignature();
#ifdef _WIN32
    if (baseKey)
    {
        if (reset)
        {
            RegSetValueExW(baseKey, valueName, 0, REG_SZ,
                           (const BYTE*)rasenh,
                           sizeof(rasenh));
        }
        RegCloseKey(baseKey);
    }
#endif


    if (rv == OK)
    {
        if (rv == OK)
        {
            NS_tchar updateSettingsPath[MAX_TEXT_LEN];

            // TODO: moggi: needs adaptation for LibreOffice
            // These paths need to be adapted for us.
            int nWrittenBytes = NS_tsnprintf(updateSettingsPath,
                         sizeof(updateSettingsPath) / sizeof(updateSettingsPath[0]),
#ifdef MACOSX
                         NS_T("%s/Contents/Resources/update-settings.ini"),
#else
                         NS_T("%s/update-settings.ini"),
#endif
                         gWorkingDirPath);
            (void) nWrittenBytes;
            MARChannelStringTable MARStrings;
            if (ReadMARChannelIDs(updateSettingsPath, &MARStrings) != OK)
            {
                // If we can't read from update-settings.ini then we shouldn't impose
                // a MAR restriction.  Some installations won't even include this file.
                MARStrings.MARChannelID[0] = '\0';
            }

            rv = archiveReader.VerifyProductInformation(MARStrings.MARChannelID,
                    LIBO_VERSION_DOTTED);
        }
    }
#endif

    return rv;
}

static void
UpdateThreadFunc(void * /*param*/)
{
    // open ZIP archive and process...
    int rv = OK;
    if (sReplaceRequest)
    {
        rv = ProcessReplaceRequest();
    }
    else
    {
        std::vector<tstring> fileNames;
        GetUpdateFileNames(fileNames);

        for (auto& fileName: fileNames)
        {
            ArchiveReader archiveReader;
            rv = archiveReader.Open(fileName.c_str());
            if (rv != OK)
            {
                LOG(("Could not open " LOG_S, fileName.c_str()));
                break;
            }

            rv = CheckSignature(archiveReader);
            if (rv != OK)
            {
                LOG(("Could not verify the signature of " LOG_S, fileName.c_str()));
                break;
            }
        }

        if (rv == OK && sStagedUpdate)
        {
            rv = CopyInstallDirToDestDir();
        }

        if (rv == OK)
        {
            for (auto& fileName: fileNames)
            {
                ArchiveReader archiveReader;
                archiveReader.Open(fileName.c_str());
                rv = DoUpdate(archiveReader);
            }
            NS_tchar updatingDir[MAXPATHLEN];
            int nWrittenBytes = NS_tsnprintf(updatingDir, sizeof(updatingDir)/sizeof(updatingDir[0]),
                         NS_T("%s/updating"), gWorkingDirPath);
            (void) nWrittenBytes;
            ensure_remove_recursive(updatingDir);
        }
    }

    if (rv && (sReplaceRequest || sStagedUpdate))
    {
#ifdef _WIN32
        // On Windows, the current working directory of the process should be changed
        // so that it's not locked.
        if (sStagedUpdate)
        {
            NS_tchar sysDir[MAX_PATH + 1] = { L'\0' };
            if (GetSystemDirectoryW(sysDir, MAX_PATH + 1))
            {
                NS_tchdir(sysDir);
            }
        }
#endif
        ensure_remove_recursive(gWorkingDirPath);
        // When attempting to replace the application, we should fall back
        // to non-staged updates in case of a failure.  We do this by
        // setting the status to pending, exiting the updater, and
        // launching the callback application.  The callback application's
        // startup path will see the pending status, and will start the
        // updater application again in order to apply the update without
        // staging.
        if (sReplaceRequest)
        {
            WriteStatusFile(sUsingService ? "pending-service" : "pending");
        }
        else
        {
            WriteStatusFile(rv);
        }
#ifdef TEST_UPDATER
        // Some tests need to use --test-process-updates again.
        putenv(const_cast<char*>("MOZ_TEST_PROCESS_UPDATES="));
#endif
    }
    else
    {
        if (rv)
        {
            LOG(("failed: %d", rv));
        }
        else
        {
#ifdef MACOSX
            // If the update was successful we need to update the timestamp on the
            // top-level macOS bundle directory so that macOS's Launch Services
            // picks up any major changes when the bundle is updated.
            if (!sStagedUpdate && utimes(gInstallDirPath, nullptr) != 0)
            {
                LOG(("Couldn't set access/modification time on application bundle."));
            }
#endif

            LOG(("succeeded"));
        }
        WriteStatusFile(rv);
    }

    LOG(("calling QuitProgressUI"));
    QuitProgressUI();
}

#ifdef MACOSX
static void
ServeElevatedUpdateThreadFunc(void* param)
{
    UpdateServerThreadArgs* threadArgs = (UpdateServerThreadArgs*)param;
    gSucceeded = ServeElevatedUpdate(threadArgs->argc, threadArgs->argv);
    if (!gSucceeded)
    {
        WriteStatusFile(ELEVATION_CANCELED);
    }
    QuitProgressUI();
}

void freeArguments(int argc, char** argv)
{
    for (int i = 0; i < argc; i++)
    {
        free(argv[i]);
    }
    free(argv);
}
#endif

int LaunchCallbackAndPostProcessApps(int argc, NS_tchar** argv,
                                     int callbackIndex
#ifdef _WIN32
                                     , const WCHAR* elevatedLockFilePath
                                     , HANDLE updateLockFileHandle
#elif defined(MACOSX)
                                     , bool isElevated
#endif
                                    )
{
    if (argc > callbackIndex)
    {
#if defined(_WIN32)
        if (gSucceeded)
        {
            if (!LaunchWinPostProcess(gInstallDirPath, gPatchDirPath))
            {
                fprintf(stderr, "The post update process was not launched");
            }

            // The service update will only be executed if it is already installed.
            // For first time installs of the service, the install will happen from
            // the PostUpdate process. We do the service update process here
            // because it's possible we are updating with updater.exe without the
            // service if the service failed to apply the update. We want to update
            // the service to a newer version in that case. If we are not running
            // through the service, then USING_SERVICE will not exist.
            if (!sUsingService)
            {
                StartServiceUpdate(gInstallDirPath);
            }
        }
        EXIT_WHEN_ELEVATED(elevatedLockFilePath, updateLockFileHandle, 0);
#elif defined(MACOSX)
        if (!isElevated)
        {
            if (gSucceeded)
            {
                LaunchMacPostProcess(gInstallDirPath);
            }
#endif

        LaunchCallbackApp(argv[5],
                          argc - callbackIndex,
                          argv + callbackIndex,
                          sUsingService);
#ifdef XP_MACOSX
    } // if (!isElevated)
#endif /* XP_MACOSX */
}
return 0;
}

int NS_main(int argc, NS_tchar **argv)
{
    // The callback is the remaining arguments starting at callbackIndex.
    // The argument specified by callbackIndex is the callback executable and the
    // argument prior to callbackIndex is the working directory.
    const int callbackIndex = 6;

#ifdef MACOSX
    // TODO: moggi: needs adaptation for LibreOffice
    bool isElevated =
        strstr(argv[0], "/Library/PrivilegedHelperTools/org.mozilla.updater") != 0;
    if (isElevated)
    {
        if (!ObtainUpdaterArguments(&argc, &argv))
        {
            // Won't actually get here because ObtainUpdaterArguments will terminate
            // the current process on failure.
            return 1;
        }
    }
#endif

#if defined(VERIFY_MAR_SIGNATURE) && !defined(_WIN32) && !defined(MACOSX)
    // On Windows and Mac we rely on native APIs to do verifications so we don't
    // need to initialize NSS at all there.
    // Otherwise, minimize the amount of NSS we depend on by avoiding all the NSS
    // databases.
    if (NSS_NoDB_Init(NULL) != SECSuccess)
    {
        PRErrorCode error = PR_GetError();
        fprintf(stderr, "Could not initialize NSS: %s (%d)",
                PR_ErrorToName(error), (int) error);
        _exit(1);
    }
#endif

#ifdef MACOSX
    if (!isElevated)
    {
#endif
        InitProgressUI(&argc, &argv);
#ifdef MACOSX
    }
#endif

    // To process an update the updater command line must at a minimum have the
    // directory path containing the updater.mar file to process as the first
    // argument, the install directory as the second argument, and the directory
    // to apply the update to as the third argument. When the updater is launched
    // by another process the PID of the parent process should be provided in the
    // optional fourth argument and the updater will wait on the parent process to
    // exit if the value is non-zero and the process is present. This is necessary
    // due to not being able to update files that are in use on Windows. The
    // optional fifth argument is the callback's working directory and the
    // optional sixth argument is the callback path. The callback is the
    // application to launch after updating and it will be launched when these
    // arguments are provided whether the update was successful or not. All
    // remaining arguments are optional and are passed to the callback when it is
    // launched.
    if (argc < 4)
    {
        fprintf(stderr, "Usage: updater patch-dir install-dir apply-to-dir [wait-pid [callback-working-dir callback-path args...]]\n");
#ifdef MACOSX
        if (isElevated)
        {
            freeArguments(argc, argv);
            CleanupElevatedMacUpdate(true);
        }
#endif
        return 1;
    }

    // The directory containing the update information.
    gPatchDirPath = argv[1];

    // The directory we're going to update to.
    // We copy this string because we need to remove trailing slashes.  The C++
    // standard says that it's always safe to write to strings pointed to by argv
    // elements, but I don't necessarily believe it.
    NS_tstrncpy(gInstallDirPath, argv[2], MAXPATHLEN);
    gInstallDirPath[MAXPATHLEN - 1] = NS_T('\0');
    NS_tchar *slash = NS_tstrrchr(gInstallDirPath, NS_SLASH);
    if (slash && !slash[1])
    {
        *slash = NS_T('\0');
    }

#ifdef _WIN32
    bool useService = false;
    bool testOnlyFallbackKeyExists = false;
    bool noServiceFallback = false;

    // We never want the service to be used unless we build with
    // the maintenance service.
#ifdef MAINTENANCE_SERVICE
    useService = IsUpdateStatusPendingService();
    // Our tests run with a different apply directory for each test.
    // We use this registry key on our test slaves to store the
    // allowed name/issuers.
    testOnlyFallbackKeyExists = DoesFallbackKeyExist();
#endif

    // Remove everything except close window from the context menu
    {
        // TODO: moggi: needs adaptation for LibreOffice
        HKEY hkApp = nullptr;
        RegCreateKeyExW(HKEY_CURRENT_USER, L"Software\\Classes\\Applications",
                        0, nullptr, REG_OPTION_NON_VOLATILE, KEY_SET_VALUE, nullptr,
                        &hkApp, nullptr);
        RegCloseKey(hkApp);
        if (RegCreateKeyExW(HKEY_CURRENT_USER,
                            L"Software\\Classes\\Applications\\updater.exe",
                            0, nullptr, REG_OPTION_VOLATILE, KEY_SET_VALUE, nullptr,
                            &hkApp, nullptr) == ERROR_SUCCESS)
        {
            RegSetValueExW(hkApp, L"IsHostApp", 0, REG_NONE, 0, 0);
            RegSetValueExW(hkApp, L"NoOpenWith", 0, REG_NONE, 0, 0);
            RegSetValueExW(hkApp, L"NoStartPage", 0, REG_NONE, 0, 0);
            RegCloseKey(hkApp);
        }
    }
#endif

    // If there is a PID specified and it is not '0' then wait for the process to exit.
#ifdef _WIN32
    __int64 pid = 0;
#else
    int pid = 0;
#endif
    if (argc > 4)
    {
#ifdef _WIN32
        pid = _wtoi64(argv[4]);
#else
        pid = atoi(argv[4]);
#endif
        if (pid == -1)
        {
            // This is a signal from the parent process that the updater should stage
            // the update.
            sStagedUpdate = true;
        }
        else if (NS_tstrstr(argv[4], NS_T("/replace")))
        {
            // We're processing a request to replace the application with a staged
            // update.
            sReplaceRequest = true;
        }
    }

    // The directory we're going to update to.
    // We copy this string because we need to remove trailing slashes.  The C++
    // standard says that it's always safe to write to strings pointed to by argv
    // elements, but I don't necessarily believe it.
    NS_tstrncpy(gWorkingDirPath, argv[3], MAXPATHLEN);
    gWorkingDirPath[MAXPATHLEN - 1] = NS_T('\0');
    slash = NS_tstrrchr(gWorkingDirPath, NS_SLASH);
    if (slash && !slash[1])
    {
        *slash = NS_T('\0');
    }

#ifdef MACOSX
    if (!isElevated && !IsRecursivelyWritable(argv[2]))
    {
        // If the app directory isn't recursively writeable, an elevated update is
        // required.
        UpdateServerThreadArgs threadArgs;
        threadArgs.argc = argc;
        threadArgs.argv = const_cast<const NS_tchar**>(argv);

        Thread t1;
        if (t1.Run(ServeElevatedUpdateThreadFunc, &threadArgs) == 0)
        {
            // Show an indeterminate progress bar while an elevated update is in
            // progress.
            ShowProgressUI(true);
        }
        t1.Join();

        LaunchCallbackAndPostProcessApps(argc, argv, callbackIndex, false);
        return gSucceeded ? 0 : 1;
    }
#endif

    LogInit(gPatchDirPath, NS_T("update.log"));

    if (!WriteStatusFile("applying"))
    {
        LOG(("failed setting status to 'applying'"));
#ifdef MACOSX
        if (isElevated)
        {
            freeArguments(argc, argv);
            CleanupElevatedMacUpdate(true);
        }
#endif
        return 1;
    }

    if (sStagedUpdate)
    {
        LOG(("Performing a staged update"));
    }
    else if (sReplaceRequest)
    {
        LOG(("Performing a replace request"));
    }

    LOG(("PATCH DIRECTORY " LOG_S, gPatchDirPath));
    LOG(("INSTALLATION DIRECTORY " LOG_S, gInstallDirPath));
    LOG(("WORKING DIRECTORY " LOG_S, gWorkingDirPath));

#ifdef _WIN32
    if (_wcsnicmp(gWorkingDirPath, gInstallDirPath, MAX_PATH) != 0)
    {
        if (!sStagedUpdate && !sReplaceRequest)
        {
            WriteStatusFile(INVALID_APPLYTO_DIR_ERROR);
            LOG(("Installation directory and working directory must be the same "
                 "for non-staged updates. Exiting."));
            LogFinish();
            return 1;
        }

        NS_tchar workingDirParent[MAX_PATH];
        NS_tsnprintf(workingDirParent,
                     sizeof(workingDirParent) / sizeof(workingDirParent[0]),
                     NS_T("%s"), gWorkingDirPath);
        if (!PathRemoveFileSpecW(workingDirParent))
        {
            WriteStatusFile(REMOVE_FILE_SPEC_ERROR);
            LOG(("Error calling PathRemoveFileSpecW: %d", GetLastError()));
            LogFinish();
            return 1;
        }

        if (_wcsnicmp(workingDirParent, gInstallDirPath, MAX_PATH) != 0)
        {
            WriteStatusFile(INVALID_APPLYTO_DIR_STAGED_ERROR);
            LOG(("The apply-to directory must be the same as or "
                 "a child of the installation directory! Exiting."));
            LogFinish();
            return 1;
        }
    }
#endif


#ifdef _WIN32
    if (pid > 0)
    {
        HANDLE parent = OpenProcess(SYNCHRONIZE, false, (DWORD) pid);
        // May return nullptr if the parent process has already gone away.
        // Otherwise, wait for the parent process to exit before starting the
        // update.
        if (parent)
        {
            DWORD waitTime = PARENT_WAIT;
            DWORD result = WaitForSingleObject(parent, waitTime);
            CloseHandle(parent);
            if (result != WAIT_OBJECT_0)
                return 1;
        }
    }
#else
    if (pid > 0)
        waitpid(pid, nullptr, 0);
#endif

#if defined(_WIN32)
#ifdef MAINTENANCE_SERVICE
    sUsingService = EnvHasValue("USING_SERVICE");
    putenv(const_cast<char*>("USING_SERVICE="));
#endif
    // lastFallbackError keeps track of the last error for the service not being
    // used, in case of an error when fallback is not enabled we write the
    // error to the update.status file.
    // When fallback is disabled (MOZ_NO_SERVICE_FALLBACK does not exist) then
    // we will instead fallback to not using the service and display a UAC prompt.
    int lastFallbackError = FALLBACKKEY_UNKNOWN_ERROR;

    // Launch a second instance of the updater with the runas verb on Windows
    // when write access is denied to the installation directory.
    HANDLE updateLockFileHandle = INVALID_HANDLE_VALUE;
    NS_tchar elevatedLockFilePath[MAXPATHLEN] = {NS_T('\0')};
    if (!sUsingService &&
            (argc > callbackIndex || sStagedUpdate || sReplaceRequest))
    {
        NS_tchar updateLockFilePath[MAXPATHLEN];
        if (sStagedUpdate)
        {
            // When staging an update, the lock file is:
            // <install_dir>\updated.update_in_progress.lock
            NS_tsnprintf(updateLockFilePath,
                         sizeof(updateLockFilePath)/sizeof(updateLockFilePath[0]),
                         NS_T("%s/updated.update_in_progress.lock"), gInstallDirPath);
        }
        else if (sReplaceRequest)
        {
            // When processing a replace request, the lock file is:
            // <install_dir>\..\moz_update_in_progress.lock
            NS_tchar installDir[MAXPATHLEN];
            NS_tstrcpy(installDir, gInstallDirPath);
            NS_tchar *slash = (NS_tchar *) NS_tstrrchr(installDir, NS_SLASH);
            *slash = NS_T('\0');
            NS_tsnprintf(updateLockFilePath,
                         sizeof(updateLockFilePath)/sizeof(updateLockFilePath[0]),
                         NS_T("%s\\moz_update_in_progress.lock"), installDir);
        }
        else
        {
            // In the non-staging update case, the lock file is:
            // <install_dir>\<app_name>.exe.update_in_progress.lock
            NS_tsnprintf(updateLockFilePath,
                         sizeof(updateLockFilePath)/sizeof(updateLockFilePath[0]),
                         NS_T("%s.update_in_progress.lock"), argv[callbackIndex]);
        }

        // The update_in_progress.lock file should only exist during an update. In
        // case it exists attempt to remove it and exit if that fails to prevent
        // simultaneous updates occurring.
        if (!_waccess(updateLockFilePath, F_OK) &&
                NS_tremove(updateLockFilePath) != 0)
        {
            // Try to fall back to the old way of doing updates if a staged
            // update fails.
            if (sStagedUpdate || sReplaceRequest)
            {
                // Note that this could fail, but if it does, there isn't too much we
                // can do in order to recover anyways.
                WriteStatusFile("pending");
            }
            LOG(("Update already in progress! Exiting"));
            return 1;
        }

        updateLockFileHandle = CreateFileW(updateLockFilePath,
                                           GENERIC_READ | GENERIC_WRITE,
                                           0,
                                           nullptr,
                                           OPEN_ALWAYS,
                                           FILE_FLAG_DELETE_ON_CLOSE,
                                           nullptr);

        NS_tsnprintf(elevatedLockFilePath,
                     sizeof(elevatedLockFilePath)/sizeof(elevatedLockFilePath[0]),
                     NS_T("%s/update_elevated.lock"), gPatchDirPath);

        // Even if a file has no sharing access, you can still get its attributes
        bool startedFromUnelevatedUpdater =
            GetFileAttributesW(elevatedLockFilePath) != INVALID_FILE_ATTRIBUTES;

        // If we're running from the service, then we were started with the same
        // token as the service so the permissions are already dropped.  If we're
        // running from an elevated updater that was started from an unelevated
        // updater, then we drop the permissions here. We do not drop the
        // permissions on the originally called updater because we use its token
        // to start the callback application.
        if (startedFromUnelevatedUpdater)
        {
            // Disable every privilege we don't need. Processes started using
            // CreateProcess will use the same token as this process.
            UACHelper::DisablePrivileges(nullptr);
        }

        if (updateLockFileHandle == INVALID_HANDLE_VALUE ||
                (useService && testOnlyFallbackKeyExists && noServiceFallback))
        {
            if (!_waccess(elevatedLockFilePath, F_OK) &&
                    NS_tremove(elevatedLockFilePath) != 0)
            {
                fprintf(stderr, "Unable to create elevated lock file! Exiting\n");
                return 1;
            }

            HANDLE elevatedFileHandle;
            elevatedFileHandle = CreateFileW(elevatedLockFilePath,
                                             GENERIC_READ | GENERIC_WRITE,
                                             0,
                                             nullptr,
                                             OPEN_ALWAYS,
                                             FILE_FLAG_DELETE_ON_CLOSE,
                                             nullptr);

            if (elevatedFileHandle == INVALID_HANDLE_VALUE)
            {
                LOG(("Unable to create elevated lock file! Exiting"));
                return 1;
            }

            wchar_t *cmdLine = MakeCommandLine(argc - 1, argv + 1);
            if (!cmdLine)
            {
                CloseHandle(elevatedFileHandle);
                return 1;
            }

            // Make sure the path to the updater to use for the update is on local.
            // We do this check to make sure that file locking is available for
            // race condition security checks.
            if (useService)
            {
                BOOL isLocal = FALSE;
                useService = IsLocalFile(argv[0], isLocal) && isLocal;
            }

            // If we have unprompted elevation we should NOT use the service
            // for the update. Service updates happen with the SYSTEM account
            // which has more privs than we need to update with.
            // Windows 8 provides a user interface so users can configure this
            // behavior and it can be configured in the registry in all Windows
            // versions that support UAC.
            if (useService)
            {
                BOOL unpromptedElevation;
                if (IsUnpromptedElevation(unpromptedElevation))
                {
                    useService = !unpromptedElevation;
                }
            }

            // Make sure the service registry entries for the installation path
            // are available.  If not don't use the service.
            if (useService)
            {
                WCHAR maintenanceServiceKey[MAX_PATH + 1];
                // TODO: moggi: needs adaptation for LibreOffice
                // Most likely the registry part is not correct yet
                if (CalculateRegistryPathFromFilePath(gInstallDirPath,
                                                      maintenanceServiceKey))
                {
                    HKEY baseKey = nullptr;
                    if (RegOpenKeyExW(HKEY_LOCAL_MACHINE,
                                      maintenanceServiceKey, 0,
                                      KEY_READ | KEY_WOW64_64KEY,
                                      &baseKey) == ERROR_SUCCESS)
                    {
                        RegCloseKey(baseKey);
                    }
                    else
                    {
#ifdef TEST_UPDATER
                        useService = testOnlyFallbackKeyExists;
#endif
                        if (!useService)
                        {
                            lastFallbackError = FALLBACKKEY_NOKEY_ERROR;
                        }
                    }
                }
                else
                {
                    useService = false;
                    lastFallbackError = FALLBACKKEY_REGPATH_ERROR;
                }
            }

            // Originally we used to write "pending" to update.status before
            // launching the service command.  This is no longer needed now
            // since the service command is launched from updater.exe.  If anything
            // fails in between, we can fall back to using the normal update process
            // on our own.

            // If we still want to use the service try to launch the service
            // command for the update.
            if (useService)
            {
                // If the update couldn't be started, then set useService to false so
                // we do the update the old way.
                DWORD ret = LaunchServiceSoftwareUpdateCommand(argc, (LPCWSTR *)argv);
                useService = (ret == ERROR_SUCCESS);
                // If the command was launched then wait for the service to be done.
                if (useService)
                {
                    bool showProgressUI = false;
                    // Never show the progress UI when staging updates.
                    if (!sStagedUpdate)
                    {
                        // We need to call this separately instead of allowing ShowProgressUI
                        // to initialize the strings because the service will move the
                        // ini file out of the way when running updater.
                        showProgressUI = !InitProgressUIStrings();
                    }

                    // Wait for the service to stop for 5 seconds.  If the service
                    // has still not stopped then show an indeterminate progress bar.
                    DWORD lastState = WaitForServiceStop(SVC_NAME, 5);
                    if (lastState != SERVICE_STOPPED)
                    {
                        std::thread waitThread(WaitForServiceFinishThread, nullptr);
                        if (showProgressUI)
                        {
                            ShowProgressUI(true, false);
                        }
                        waitThread.join();
                    }

                    lastState = WaitForServiceStop(SVC_NAME, 1);
                    if (lastState != SERVICE_STOPPED)
                    {
                        // If the service doesn't stop after 10 minutes there is
                        // something seriously wrong.
                        lastFallbackError = FALLBACKKEY_SERVICE_NO_STOP_ERROR;
                        useService = false;
                    }
                }
                else
                {
                    lastFallbackError = FALLBACKKEY_LAUNCH_ERROR;
                }
            }

            // If the service can't be used when staging and update, make sure that
            // the UAC prompt is not shown! In this case, just set the status to
            // pending and the update will be applied during the next startup.
            if (!useService && sStagedUpdate)
            {
                if (updateLockFileHandle != INVALID_HANDLE_VALUE)
                {
                    CloseHandle(updateLockFileHandle);
                }
                WriteStatusFile("pending");
                return 0;
            }

            // If we started the service command, and it finished, check the
            // update.status file to make sure it succeeded, and if it did
            // we need to manually start the PostUpdate process from the
            // current user's session of this unelevated updater.exe the
            // current process is running as.
            // Note that we don't need to do this if we're just staging the update,
            // as the PostUpdate step runs when performing the replacing in that case.
            if (useService && !sStagedUpdate)
            {
                bool updateStatusSucceeded = false;
                if (IsUpdateStatusSucceeded(updateStatusSucceeded) &&
                        updateStatusSucceeded)
                {
                    if (!LaunchWinPostProcess(gInstallDirPath, gPatchDirPath))
                    {
                        fprintf(stderr, "The post update process which runs as the user"
                                " for service update could not be launched.");
                    }
                }
            }

            // If we didn't want to use the service at all, or if an update was
            // already happening, or launching the service command failed, then
            // launch the elevated updater.exe as we do without the service.
            // We don't launch the elevated updater in the case that we did have
            // write access all along because in that case the only reason we're
            // using the service is because we are testing.
            if (!useService && !noServiceFallback &&
                    updateLockFileHandle == INVALID_HANDLE_VALUE)
            {
                SHELLEXECUTEINFO sinfo;
                memset(&sinfo, 0, sizeof(SHELLEXECUTEINFO));
                sinfo.cbSize       = sizeof(SHELLEXECUTEINFO);
                sinfo.fMask        = SEE_MASK_FLAG_NO_UI |
                                     SEE_MASK_FLAG_DDEWAIT |
                                     SEE_MASK_NOCLOSEPROCESS;
                sinfo.hwnd         = nullptr;
                sinfo.lpFile       = argv[0];
                sinfo.lpParameters = cmdLine;
                sinfo.lpVerb       = L"runas";
                sinfo.nShow        = SW_SHOWNORMAL;

                bool result = ShellExecuteEx(&sinfo);
                free(cmdLine);

                if (result)
                {
                    WaitForSingleObject(sinfo.hProcess, INFINITE);
                    CloseHandle(sinfo.hProcess);
                }
                else
                {
                    WriteStatusFile(ELEVATION_CANCELED);
                }
            }

            if (argc > callbackIndex)
            {
                LaunchCallbackApp(argv[5], argc - callbackIndex,
                                  argv + callbackIndex, sUsingService);
            }

            CloseHandle(elevatedFileHandle);

            if (!useService && !noServiceFallback &&
                    INVALID_HANDLE_VALUE == updateLockFileHandle)
            {
                // We didn't use the service and we did run the elevated updater.exe.
                // The elevated updater.exe is responsible for writing out the
                // update.status file.
                return 0;
            }
            else if (useService)
            {
                // The service command was launched. The service is responsible for
                // writing out the update.status file.
                if (updateLockFileHandle != INVALID_HANDLE_VALUE)
                {
                    CloseHandle(updateLockFileHandle);
                }
                return 0;
            }
            else
            {
                // Otherwise the service command was not launched at all.
                // We are only reaching this code path because we had write access
                // all along to the directory and a fallback key existed, and we
                // have fallback disabled (MOZ_NO_SERVICE_FALLBACK env var exists).
                // We only currently use this env var from XPCShell tests.
                CloseHandle(updateLockFileHandle);
                WriteStatusFile(lastFallbackError);
                return 0;
            }
        }
    }
#endif

    if (sStagedUpdate)
    {
        // When staging updates, blow away the old installation directory and create
        // it from scratch.
        ensure_remove_recursive(gWorkingDirPath);
    }
    if (!sReplaceRequest)
    {
        // Try to create the destination directory if it doesn't exist
        int rv = NS_tmkdir(gWorkingDirPath, 0755);
        if (rv != OK && errno != EEXIST)
        {
#ifdef MACOSX
            if (isElevated)
            {
                freeArguments(argc, argv);
                CleanupElevatedMacUpdate(true);
            }
#endif
            return 1;
        }
    }

#ifdef _WIN32
    // For replace requests, we don't need to do any real updates, so this is not
    // necessary.
    if (!sReplaceRequest)
    {
        // Allocate enough space for the length of the path an optional additional
        // trailing slash and null termination.
        NS_tchar *destpath = (NS_tchar *) malloc((NS_tstrlen(gWorkingDirPath) + 2) * sizeof(NS_tchar));
        if (!destpath)
            return 1;

        NS_tchar *c = destpath;
        NS_tstrcpy(c, gWorkingDirPath);
        c += NS_tstrlen(gWorkingDirPath);
        if (gWorkingDirPath[NS_tstrlen(gWorkingDirPath) - 1] != NS_T('/') &&
                gWorkingDirPath[NS_tstrlen(gWorkingDirPath) - 1] != NS_T('\\'))
        {
            NS_tstrcat(c, NS_T("/"));
            c += NS_tstrlen(NS_T("/"));
        }
        *c = NS_T('\0');
        c++;

        gDestPath = destpath;
    }

    NS_tchar applyDirLongPath[MAXPATHLEN];
    if (!GetLongPathNameW(gWorkingDirPath, applyDirLongPath,
                          sizeof(applyDirLongPath)/sizeof(applyDirLongPath[0])))
    {
        LOG(("NS_main: unable to find apply to dir: " LOG_S, gWorkingDirPath));
        LogFinish();
        WriteStatusFile(WRITE_ERROR_APPLY_DIR_PATH);
        EXIT_WHEN_ELEVATED(elevatedLockFilePath, updateLockFileHandle, 1);
        if (argc > callbackIndex)
        {
            LaunchCallbackApp(argv[5], argc - callbackIndex,
                              argv + callbackIndex, sUsingService);
        }
        return 1;
    }

    HANDLE callbackFile = INVALID_HANDLE_VALUE;
    if (argc > callbackIndex)
    {
        // If the callback executable is specified it must exist for a successful
        // update.  It is important we null out the whole buffer here because later
        // we make the assumption that the callback application is inside the
        // apply-to dir.  If we don't have a fully null'ed out buffer it can lead
        // to stack corruption which causes crashes and other problems.
        NS_tchar callbackLongPath[MAXPATHLEN];
        ZeroMemory(callbackLongPath, sizeof(callbackLongPath));
        NS_tchar *targetPath = argv[callbackIndex];
        NS_tchar buffer[MAXPATHLEN * 2] = { NS_T('\0') };
        size_t bufferLeft = MAXPATHLEN * 2;
        if (sReplaceRequest)
        {
            // In case of replace requests, we should look for the callback file in
            // the destination directory.
            size_t commonPrefixLength = PathCommonPrefixW(argv[callbackIndex],
                                        gInstallDirPath,
                                        nullptr);
            NS_tchar *p = buffer;
            NS_tstrncpy(p, argv[callbackIndex], commonPrefixLength);
            p += commonPrefixLength;
            bufferLeft -= commonPrefixLength;
            NS_tstrncpy(p, gInstallDirPath + commonPrefixLength, bufferLeft);

            size_t len = NS_tstrlen(gInstallDirPath + commonPrefixLength);
            p += len;
            bufferLeft -= len;
            *p = NS_T('\\');
            ++p;
            bufferLeft--;
            *p = NS_T('\0');
            NS_tchar installDir[MAXPATHLEN];
            NS_tstrcpy(installDir, gInstallDirPath);
            size_t callbackPrefixLength = PathCommonPrefixW(argv[callbackIndex],
                                          installDir,
                                          nullptr);
            NS_tstrncpy(p, argv[callbackIndex] + std::max(callbackPrefixLength,
                        commonPrefixLength), bufferLeft);
            targetPath = buffer;
        }
        if (!GetLongPathNameW(targetPath, callbackLongPath,
                              sizeof(callbackLongPath)/sizeof(callbackLongPath[0])))
        {
            LOG(("NS_main: unable to find callback file: " LOG_S, targetPath));
            LogFinish();
            WriteStatusFile(WRITE_ERROR_CALLBACK_PATH);
            EXIT_WHEN_ELEVATED(elevatedLockFilePath, updateLockFileHandle, 1);
            if (argc > callbackIndex)
            {
                LaunchCallbackApp(argv[5],
                                  argc - callbackIndex,
                                  argv + callbackIndex,
                                  sUsingService);
            }
            return 1;
        }

        // Doing this is only necessary when we're actually applying a patch.
        if (!sReplaceRequest)
        {
            int len = NS_tstrlen(applyDirLongPath);
            NS_tchar *s = callbackLongPath;
            NS_tchar *d = gCallbackRelPath;
            // advance to the apply to directory and advance past the trailing backslash
            // if present.
            s += len;
            if (*s == NS_T('\\'))
                ++s;

            // Copy the string and replace backslashes with forward slashes along the
            // way.
            do
            {
                if (*s == NS_T('\\'))
                    *d = NS_T('/');
                else
                    *d = *s;
                ++s;
                ++d;
            }
            while (*s);
            *d = NS_T('\0');
            ++d;

            // Make a copy of the callback executable so it can be read when patching.
            NS_tsnprintf(gCallbackBackupPath,
                         sizeof(gCallbackBackupPath)/sizeof(gCallbackBackupPath[0]),
                         NS_T("%s" CALLBACK_BACKUP_EXT), argv[callbackIndex]);
            NS_tremove(gCallbackBackupPath);
            if (!CopyFileW(argv[callbackIndex], gCallbackBackupPath, true))
            {
                DWORD copyFileError = GetLastError();
                LOG(("NS_main: failed to copy callback file " LOG_S
                     " into place at " LOG_S, argv[callbackIndex], gCallbackBackupPath));
                LogFinish();
                if (copyFileError == ERROR_ACCESS_DENIED)
                {
                    WriteStatusFile(WRITE_ERROR_ACCESS_DENIED);
                }
                else
                {
                    WriteStatusFile(WRITE_ERROR_CALLBACK_APP);
                }

                EXIT_WHEN_ELEVATED(elevatedLockFilePath, updateLockFileHandle, 1);
                LaunchCallbackApp(argv[callbackIndex],
                                  argc - callbackIndex,
                                  argv + callbackIndex,
                                  sUsingService);
                return 1;
            }

            // Since the process may be signaled as exited by WaitForSingleObject before
            // the release of the executable image try to lock the main executable file
            // multiple times before giving up.  If we end up giving up, we won't
            // fail the update.
            const int max_retries = 10;
            int retries = 1;
            DWORD lastWriteError = 0;
            do
            {
                // By opening a file handle without FILE_SHARE_READ to the callback
                // executable, the OS will prevent launching the process while it is
                // being updated.
                callbackFile = CreateFileW(targetPath,
                                           DELETE | GENERIC_WRITE,
                                           // allow delete, rename, and write
                                           FILE_SHARE_DELETE | FILE_SHARE_WRITE,
                                           nullptr, OPEN_EXISTING, 0, nullptr);
                if (callbackFile != INVALID_HANDLE_VALUE)
                    break;

                lastWriteError = GetLastError();
                LOG(("NS_main: callback app file open attempt %d failed. " \
                     "File: " LOG_S ". Last error: %d", retries,
                     targetPath, lastWriteError));

                Sleep(100);
            }
            while (++retries <= max_retries);

            // CreateFileW will fail if the callback executable is already in use.
            if (callbackFile == INVALID_HANDLE_VALUE)
            {
                // Only fail the update if the last error was not a sharing violation.
                if (lastWriteError != ERROR_SHARING_VIOLATION)
                {
                    LOG(("NS_main: callback app file in use, failed to exclusively open " \
                         "executable file: " LOG_S, argv[callbackIndex]));
                    LogFinish();
                    if (lastWriteError == ERROR_ACCESS_DENIED)
                    {
                        WriteStatusFile(WRITE_ERROR_ACCESS_DENIED);
                    }
                    else
                    {
                        WriteStatusFile(WRITE_ERROR_CALLBACK_APP);
                    }

                    NS_tremove(gCallbackBackupPath);
                    EXIT_WHEN_ELEVATED(elevatedLockFilePath, updateLockFileHandle, 1);
                    LaunchCallbackApp(argv[5],
                                      argc - callbackIndex,
                                      argv + callbackIndex,
                                      sUsingService);
                    return 1;
                }
                LOG(("NS_main: callback app file in use, continuing without " \
                     "exclusive access for executable file: " LOG_S,
                     argv[callbackIndex]));
            }
        }
    }

    // DELETE_DIR is not required when performing a staged update or replace
    // request; it can be used during a replace request but then it doesn't
    // use gDeleteDirPath.
    if (!sStagedUpdate && !sReplaceRequest)
    {
        // The directory to move files that are in use to on Windows. This directory
        // will be deleted after the update is finished, on OS reboot using
        // MoveFileEx if it contains files that are in use, or by the post update
        // process after the update finishes. On Windows when performing a normal
        // update (e.g. the update is not a staged update and is not a replace
        // request) gWorkingDirPath is the same as gInstallDirPath and
        // gWorkingDirPath is used because it is the destination directory.
        NS_tsnprintf(gDeleteDirPath,
                     sizeof(gDeleteDirPath) / sizeof(gDeleteDirPath[0]),
                     NS_T("%s/%s"), gWorkingDirPath, DELETE_DIR);

        if (NS_taccess(gDeleteDirPath, F_OK))
        {
            NS_tmkdir(gDeleteDirPath, 0755);
        }
    }
#endif /* _WIN32 */

    // Run update process on a background thread. ShowProgressUI may return
    // before QuitProgressUI has been called, so wait for UpdateThreadFunc to
    // terminate. Avoid showing the progress UI when staging an update, or if this
    // is an elevated process on OSX.
    std::thread t(UpdateThreadFunc, nullptr);
    if (!sStagedUpdate && !sReplaceRequest
#ifdef XP_MACOSX
            && !isElevated
#endif
       )
    {
        ShowProgressUI();
    }
    t.join();

#ifdef _WIN32
    if (argc > callbackIndex && !sReplaceRequest)
    {
        if (callbackFile != INVALID_HANDLE_VALUE)
        {
            CloseHandle(callbackFile);
        }
        // Remove the copy of the callback executable.
        NS_tremove(gCallbackBackupPath);
    }

    if (!sStagedUpdate && !sReplaceRequest && _wrmdir(gDeleteDirPath))
    {
        LOG(("NS_main: unable to remove directory: " LOG_S ", err: %d",
             DELETE_DIR, errno));
        // The directory probably couldn't be removed due to it containing files
        // that are in use and will be removed on OS reboot. The call to remove the
        // directory on OS reboot is done after the calls to remove the files so the
        // files are removed first on OS reboot since the directory must be empty
        // for the directory removal to be successful. The MoveFileEx call to remove
        // the directory on OS reboot will fail if the process doesn't have write
        // access to the HKEY_LOCAL_MACHINE registry key but this is ok since the
        // installer / uninstaller will delete the directory along with its contents
        // after an update is applied, on reinstall, and on uninstall.
        if (MoveFileEx(gDeleteDirPath, nullptr, MOVEFILE_DELAY_UNTIL_REBOOT))
        {
            LOG(("NS_main: directory will be removed on OS reboot: " LOG_S,
                 DELETE_DIR));
        }
        else
        {
            LOG(("NS_main: failed to schedule OS reboot removal of " \
                 "directory: " LOG_S, DELETE_DIR));
        }
    }
#endif /* _WIN32 */


#ifdef MACOSX
    // When the update is successful remove the precomplete file in the root of
    // the application bundle and move the distribution directory from
    // Contents/MacOS to Contents/Resources and if both exist delete the
    // directory under Contents/MacOS (see Bug 1068439).
    if (gSucceeded && !sStagedUpdate)
    {
        NS_tchar oldPrecomplete[MAXPATHLEN];
        NS_tsnprintf(oldPrecomplete, sizeof(oldPrecomplete)/sizeof(oldPrecomplete[0]),
                     NS_T("%s/precomplete"), gInstallDirPath);
        NS_tremove(oldPrecomplete);

        NS_tchar oldDistDir[MAXPATHLEN];
        NS_tsnprintf(oldDistDir, sizeof(oldDistDir)/sizeof(oldDistDir[0]),
                     NS_T("%s/Contents/MacOS/distribution"), gInstallDirPath);
        int rv = NS_taccess(oldDistDir, F_OK);
        if (!rv)
        {
            NS_tchar newDistDir[MAXPATHLEN];
            NS_tsnprintf(newDistDir, sizeof(newDistDir)/sizeof(newDistDir[0]),
                         NS_T("%s/Contents/Resources/distribution"), gInstallDirPath);
            rv = NS_taccess(newDistDir, F_OK);
            if (!rv)
            {
                LOG(("New distribution directory already exists... removing old " \
                     "distribution directory: " LOG_S, oldDistDir));
                rv = ensure_remove_recursive(oldDistDir);
                if (rv)
                {
                    LOG(("Removing old distribution directory failed - err: %d", rv));
                }
            }
            else
            {
                LOG(("Moving old distribution directory to new location. src: " LOG_S \
                     ", dst:" LOG_S, oldDistDir, newDistDir));
                rv = rename_file(oldDistDir, newDistDir, true);
                if (rv)
                {
                    LOG(("Moving old distribution directory to new location failed - " \
                         "err: %d", rv));
                }
            }
        }
    }

    if (isElevated)
    {
        SetGroupOwnershipAndPermissions(gInstallDirPath);
        freeArguments(argc, argv);
        CleanupElevatedMacUpdate(false);
    }
    else if (IsOwnedByGroupAdmin(gInstallDirPath))
    {
        // If the group ownership of the Firefox .app bundle was set to the "admin"
        // group during a previous elevated update, we need to ensure that all files
        // in the bundle have group ownership of "admin" as well as write permission
        // for the group to not break updates in the future.
        SetGroupOwnershipAndPermissions(gInstallDirPath);
    }
#endif /* MACOSX */

    LogFinish();

    int retVal = LaunchCallbackAndPostProcessApps(argc, argv, callbackIndex
#ifdef _WIN32
                 , elevatedLockFilePath
                 , updateLockFileHandle
#elif defined(MACOSX)
                 , isElevated
#endif
                                                 );

    return retVal ? retVal : (gSucceeded ? 0 : 1);
}

class ActionList
{
public:
    ActionList() : mFirst(nullptr), mLast(nullptr), mCount(0) { }
    ~ActionList();

    void Append(Action* action);
    int Prepare();
    int Execute();
    void Finish(int status);

private:
    Action *mFirst;
    Action *mLast;
    int     mCount;
};

ActionList::~ActionList()
{
    Action* a = mFirst;
    while (a)
    {
        Action *b = a;
        a = a->mNext;
        delete b;
    }
}

void
ActionList::Append(Action *action)
{
    if (mLast)
        mLast->mNext = action;
    else
        mFirst = action;

    mLast = action;
    mCount++;
}

int
ActionList::Prepare()
{
    // If the action list is empty then we should fail in order to signal that
    // something has gone wrong. Otherwise we report success when nothing is
    // actually done. See bug 327140.
    if (mCount == 0)
    {
        LOG(("empty action list"));
        return MAR_ERROR_EMPTY_ACTION_LIST;
    }

    Action *a = mFirst;
    int i = 0;
    while (a)
    {
        int rv = a->Prepare();
        if (rv)
            return rv;

        float percent = float(++i) / float(mCount);
        UpdateProgressUI(PROGRESS_PREPARE_SIZE * percent);

        a = a->mNext;
    }

    return OK;
}

int
ActionList::Execute()
{
    int currentProgress = 0, maxProgress = 0;
    Action *a = mFirst;
    while (a)
    {
        maxProgress += a->mProgressCost;
        a = a->mNext;
    }

    a = mFirst;
    while (a)
    {
        int rv = a->Execute();
        if (rv)
        {
            LOG(("### execution failed"));
            return rv;
        }

        currentProgress += a->mProgressCost;
        float percent = float(currentProgress) / float(maxProgress);
        UpdateProgressUI(PROGRESS_PREPARE_SIZE +
                         PROGRESS_EXECUTE_SIZE * percent);

        a = a->mNext;
    }

    return OK;
}

void
ActionList::Finish(int status)
{
    Action *a = mFirst;
    int i = 0;
    while (a)
    {
        a->Finish(status);

        float percent = float(++i) / float(mCount);
        UpdateProgressUI(PROGRESS_PREPARE_SIZE +
                         PROGRESS_EXECUTE_SIZE +
                         PROGRESS_FINISH_SIZE * percent);

        a = a->mNext;
    }

    if (status == OK)
        gSucceeded = true;
}


#ifdef _WIN32
int add_dir_entries(const NS_tchar *dirpath, ActionList *list)
{
    int rv = OK;
    WIN32_FIND_DATAW finddata;
    HANDLE hFindFile;
    NS_tchar searchspec[MAXPATHLEN];
    NS_tchar foundpath[MAXPATHLEN];

    NS_tsnprintf(searchspec, sizeof(searchspec)/sizeof(searchspec[0]),
                 NS_T("%s*"), dirpath);
    std::unique_ptr<const NS_tchar[]> pszSpec(new_absolute_path(searchspec));

    hFindFile = FindFirstFileW(pszSpec.get(), &finddata);
    if (hFindFile != INVALID_HANDLE_VALUE)
    {
        do
        {
            // Don't process the current or parent directory.
            if (NS_tstrcmp(finddata.cFileName, NS_T(".")) == 0 ||
                    NS_tstrcmp(finddata.cFileName, NS_T("..")) == 0)
                continue;

            NS_tsnprintf(foundpath, sizeof(foundpath)/sizeof(foundpath[0]),
                         NS_T("%s%s"), dirpath, finddata.cFileName);
            if (finddata.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)
            {
                NS_tsnprintf(foundpath, sizeof(foundpath)/sizeof(foundpath[0]),
                             NS_T("%s/"), foundpath);
                // Recurse into the directory.
                rv = add_dir_entries(foundpath, list);
                if (rv)
                {
                    LOG(("add_dir_entries error: " LOG_S ", err: %d", foundpath, rv));
                    return rv;
                }
            }
            else
            {
                // Add the file to be removed to the ActionList.
                NS_tchar *quotedpath = get_quoted_path(foundpath);
                if (!quotedpath)
                    return PARSE_ERROR;

                Action *action = new RemoveFile();
                rv = action->Parse(quotedpath);
                if (rv)
                {
                    LOG(("add_dir_entries Parse error on recurse: " LOG_S ", err: %d",
                         quotedpath, rv));
                    return rv;
                }
                free(quotedpath);

                list->Append(action);
            }
        }
        while (FindNextFileW(hFindFile, &finddata) != 0);

        FindClose(hFindFile);
        {
            // Add the directory to be removed to the ActionList.
            NS_tchar *quotedpath = get_quoted_path(dirpath);
            if (!quotedpath)
                return PARSE_ERROR;

            Action *action = new RemoveDir();
            rv = action->Parse(quotedpath);
            if (rv)
                LOG(("add_dir_entries Parse error on close: " LOG_S ", err: %d",
                     quotedpath, rv));
            else
                list->Append(action);
            free(quotedpath);
        }
    }

    return rv;
}

#elif defined(__sun)
int add_dir_entries(const NS_tchar *dirpath, ActionList *list)
{
    int rv = OK;
    NS_tchar foundpath[MAXPATHLEN];
    struct
    {
        dirent dent_buffer;
        char chars[MAXNAMLEN];
    } ent_buf;
    struct dirent* ent;
    std::unique_ptr<NS_tchar[]> searchpath(new_absolute_path(dirpath));

    DIR* dir = opendir(searchpath.get());
    if (!dir)
    {
        LOG(("add_dir_entries error on opendir: " LOG_S ", err: %d", searchpath.get(),
             errno));
        return UNEXPECTED_FILE_OPERATION_ERROR;
    }

    while (readdir_r(dir, (dirent *)&ent_buf, &ent) == 0 && ent)
    {
        if ((strcmp(ent->d_name, ".") == 0) ||
                (strcmp(ent->d_name, "..") == 0))
            continue;

        NS_tsnprintf(foundpath, sizeof(foundpath)/sizeof(foundpath[0]),
                     NS_T("%s%s"), searchpath.get(), ent->d_name);
        struct stat64 st_buf;
        int test = stat64(foundpath, &st_buf);
        if (test)
        {
            closedir(dir);
            return UNEXPECTED_FILE_OPERATION_ERROR;
        }
        if (S_ISDIR(st_buf.st_mode))
        {
            NS_tsnprintf(foundpath, sizeof(foundpath)/sizeof(foundpath[0]),
                         NS_T("%s/"), foundpath);
            // Recurse into the directory.
            rv = add_dir_entries(foundpath, list);
            if (rv)
            {
                LOG(("add_dir_entries error: " LOG_S ", err: %d", foundpath, rv));
                closedir(dir);
                return rv;
            }
        }
        else
        {
            // Add the file to be removed to the ActionList.
            NS_tchar *quotedpath = get_quoted_path(get_relative_offset(foundpath));
            if (!quotedpath)
            {
                closedir(dir);
                return PARSE_ERROR;
            }

            Action *action = new RemoveFile();
            rv = action->Parse(quotedpath);
            if (rv)
            {
                LOG(("add_dir_entries Parse error on recurse: " LOG_S ", err: %d",
                     quotedpath, rv));
                closedir(dir);
                return rv;
            }

            list->Append(action);
        }
    }
    closedir(dir);

    // Add the directory to be removed to the ActionList.
    NS_tchar *quotedpath = get_quoted_path(get_relative_offset(dirpath));
    if (!quotedpath)
        return PARSE_ERROR;

    Action *action = new RemoveDir();
    rv = action->Parse(quotedpath);
    if (rv)
    {
        LOG(("add_dir_entries Parse error on close: " LOG_S ", err: %d",
             quotedpath, rv));
    }
    else
    {
        list->Append(action);
    }

    return rv;
}

#else

int add_dir_entries(const NS_tchar *dirpath, ActionList *list)
{
    int rv = OK;
    FTS *ftsdir;
    FTSENT *ftsdirEntry;
    std::unique_ptr<NS_tchar[]> searchpath(new_absolute_path(dirpath));

    // Remove the trailing slash so the paths don't contain double slashes. The
    // existence of the slash has already been checked in DoUpdate.
    searchpath.get()[NS_tstrlen(searchpath.get()) - 1] = NS_T('\0');
    char* const pathargv[] = {searchpath.get(), nullptr};

    // FTS_NOCHDIR is used so relative paths from the destination directory are
    // returned.
    if (!(ftsdir = fts_open(pathargv,
                            FTS_PHYSICAL | FTS_NOSTAT | FTS_XDEV | FTS_NOCHDIR,
                            nullptr)))
        return UNEXPECTED_FILE_OPERATION_ERROR;

    while ((ftsdirEntry = fts_read(ftsdir)) != nullptr)
    {
        NS_tchar foundpath[MAXPATHLEN];
        NS_tchar *quotedpath = nullptr;
        Action *action = nullptr;

        switch (ftsdirEntry->fts_info)
        {
            // Filesystem objects that shouldn't be in the application's directories
            case FTS_SL:
            case FTS_SLNONE:
            case FTS_DEFAULT:
                LOG(("add_dir_entries: found a non-standard file: " LOG_S,
                     ftsdirEntry->fts_path));
            /* Fall through */ // and try to remove as a file

            // Files
            case FTS_F:
            case FTS_NSOK:
                // Add the file to be removed to the ActionList.
                NS_tsnprintf(foundpath, sizeof(foundpath)/sizeof(foundpath[0]),
                             NS_T("%s"), ftsdirEntry->fts_accpath);
                quotedpath = get_quoted_path(get_relative_offset(foundpath));
                if (!quotedpath)
                {
                    rv = UPDATER_QUOTED_PATH_MEM_ERROR;
                    break;
                }
                action = new RemoveFile();
                rv = action->Parse(quotedpath);
                free(quotedpath);
                if (!rv)
                    list->Append(action);
                break;

            // Directories
            case FTS_DP:
                rv = OK;
                // Add the directory to be removed to the ActionList.
                NS_tsnprintf(foundpath, sizeof(foundpath)/sizeof(foundpath[0]),
                             NS_T("%s/"), ftsdirEntry->fts_accpath);
                quotedpath = get_quoted_path(get_relative_offset(foundpath));
                if (!quotedpath)
                {
                    rv = UPDATER_QUOTED_PATH_MEM_ERROR;
                    break;
                }

                action = new RemoveDir();
                rv = action->Parse(quotedpath);
                free(quotedpath);
                if (!rv)
                    list->Append(action);
                break;

            // Errors
            case FTS_DNR:
            case FTS_NS:
                // ENOENT is an acceptable error for FTS_DNR and FTS_NS and means that
                // we're racing with ourselves. Though strange, the entry will be
                // removed anyway.
                if (ENOENT == ftsdirEntry->fts_errno)
                {
                    rv = OK;
                    break;
                }
            // Fall through

            case FTS_ERR:
                rv = UNEXPECTED_FILE_OPERATION_ERROR;
                LOG(("add_dir_entries: fts_read() error: " LOG_S ", err: %d",
                     ftsdirEntry->fts_path, ftsdirEntry->fts_errno));
                break;

            case FTS_DC:
                rv = UNEXPECTED_FILE_OPERATION_ERROR;
                LOG(("add_dir_entries: fts_read() returned FT_DC: " LOG_S,
                     ftsdirEntry->fts_path));
                break;

            default:
                // FTS_D is ignored and FTS_DP is used instead (post-order).
                rv = OK;
                break;
        }

        if (rv != OK)
            break;
    }

    fts_close(ftsdir);

    return rv;
}
#endif

static NS_tchar*
GetManifestContents(const NS_tchar *manifest)
{
    AutoFile mfile(NS_tfopen(manifest, NS_T("rb")));
    if (mfile == nullptr)
    {
        LOG(("GetManifestContents: error opening manifest file: " LOG_S, manifest));
        return nullptr;
    }

    struct stat ms;
    int rv = fstat(fileno((FILE *)mfile), &ms);
    if (rv)
    {
        LOG(("GetManifestContents: error stating manifest file: " LOG_S, manifest));
        return nullptr;
    }

    char *mbuf = (char *) malloc(ms.st_size + 1);
    if (!mbuf)
        return nullptr;

    size_t r = ms.st_size;
    char *rb = mbuf;
    while (r)
    {
        const size_t count = std::min<size_t>(SSIZE_MAX, r);
        size_t c = fread(rb, 1, count, mfile);
        if (c != count)
        {
            LOG(("GetManifestContents: error reading manifest file: " LOG_S, manifest));
            free(mbuf);
            return nullptr;
        }

        r -= c;
        rb += c;
    }
    mbuf[ms.st_size] = '\0';
    rb = mbuf;

#ifndef _WIN32
    return rb;
#else
    NS_tchar *wrb = (NS_tchar *) malloc((ms.st_size + 1) * sizeof(NS_tchar));
    if (!wrb)
    {
        free(mbuf);
        return nullptr;
    }

    if (!MultiByteToWideChar(CP_UTF8, MB_ERR_INVALID_CHARS, rb, -1, wrb,
                             ms.st_size + 1))
    {
        LOG(("GetManifestContents: error converting utf8 to utf16le: %d", GetLastError()));
        free(mbuf);
        free(wrb);
        return nullptr;
    }
    free(mbuf);

    return wrb;
#endif
}

int AddPreCompleteActions(ActionList *list)
{
#ifdef MACOSX
    std::unique_ptr<NS_tchar[]> manifestPath(new_absolute_path(
            NS_T("Contents/Resources/precomplete")));
#else
    std::unique_ptr<NS_tchar[]> manifestPath(new_absolute_path(
            NS_T("precomplete")));
#endif

    NS_tchar *rb = GetManifestContents(manifestPath.get());
    if (rb == nullptr)
    {
        LOG(("AddPreCompleteActions: error getting contents of precomplete " \
             "manifest"));
        // Applications aren't required to have a precomplete manifest. The mar
        // generation scripts enforce the presence of a precomplete manifest.
        return OK;
    }

    int rv;
    NS_tchar *line;
    while ((line = mstrtok(kNL, &rb)) != 0)
    {
        // skip comments
        if (*line == NS_T('#'))
            continue;

        NS_tchar *token = mstrtok(kWhitespace, &line);
        if (!token)
        {
            LOG(("AddPreCompleteActions: token not found in manifest"));
            return PARSE_ERROR;
        }

        Action *action = nullptr;
        if (NS_tstrcmp(token, NS_T("remove")) == 0)   // rm file
        {
            action = new RemoveFile();
        }
        else if (NS_tstrcmp(token, NS_T("remove-cc")) == 0)   // no longer supported
        {
            continue;
        }
        else if (NS_tstrcmp(token, NS_T("rmdir")) == 0)   // rmdir if  empty
        {
            action = new RemoveDir();
        }
        else
        {
            LOG(("AddPreCompleteActions: unknown token: " LOG_S, token));
            return PARSE_ERROR;
        }

        if (!action)
            return BAD_ACTION_ERROR;

        rv = action->Parse(line);
        if (rv)
            return rv;

        list->Append(action);
    }

    return OK;
}

int DoUpdate(ArchiveReader& archiveReader)
{
    NS_tchar manifest[MAXPATHLEN];
    int nWrittenBytes = NS_tsnprintf(manifest, sizeof(manifest)/sizeof(manifest[0]),
                 NS_T("%s/updating/update.manifest"), gWorkingDirPath);
    (void) nWrittenBytes;
    ensure_parent_dir(manifest);

    // extract the manifest
    // TODO: moggi: needs adaptation for LibreOffice
    // Why would we need the manifest? Even if we need it why would we need 2?
    int rv = archiveReader.ExtractFile("updatev3.manifest", manifest);
    if (rv)
    {
        rv = archiveReader.ExtractFile("updatev2.manifest", manifest);
        if (rv)
        {
            LOG(("DoUpdate: error extracting manifest file"));
            return rv;
        }
    }

    NS_tchar *rb = GetManifestContents(manifest);
    NS_tremove(manifest);
    if (rb == nullptr)
    {
        LOG(("DoUpdate: error opening manifest file: " LOG_S, manifest));
        return READ_ERROR;
    }

    ActionList list;
    NS_tchar *line;
    bool isFirstAction = true;

    while ((line = mstrtok(kNL, &rb)) != 0)
    {
        // skip comments
        if (*line == NS_T('#'))
            continue;

        NS_tchar *token = mstrtok(kWhitespace, &line);
        if (!token)
        {
            LOG(("DoUpdate: token not found in manifest"));
            return PARSE_ERROR;
        }

        if (isFirstAction)
        {
            isFirstAction = false;
            // The update manifest isn't required to have a type declaration. The mar
            // generation scripts enforce the presence of the type declaration.
            if (NS_tstrcmp(token, NS_T("type")) == 0)
            {
                const NS_tchar *type = mstrtok(kQuote, &line);
                LOG(("UPDATE TYPE " LOG_S, type));
                if (NS_tstrcmp(type, NS_T("complete")) == 0)
                {
                    rv = AddPreCompleteActions(&list);
                    if (rv)
                        return rv;
                }
                continue;
            }
        }

        Action *action = nullptr;
        if (NS_tstrcmp(token, NS_T("remove")) == 0)   // rm file
        {
            action = new RemoveFile();
        }
        else if (NS_tstrcmp(token, NS_T("rmdir")) == 0)   // rmdir if empty
        {
            action = new RemoveDir();
        }
        else if (NS_tstrcmp(token, NS_T("rmrfdir")) == 0)   // rmdir recursive
        {
            const NS_tchar *reldirpath = mstrtok(kQuote, &line);
            if (!reldirpath)
                return PARSE_ERROR;

            if (reldirpath[NS_tstrlen(reldirpath) - 1] != NS_T('/'))
                return PARSE_ERROR;

            rv = add_dir_entries(reldirpath, &list);
            if (rv)
                return rv;

            continue;
        }
        else if (NS_tstrcmp(token, NS_T("add")) == 0)
        {
            action = new AddFile(archiveReader);
        }
        else if (NS_tstrcmp(token, NS_T("patch")) == 0)
        {
            action = new PatchFile(archiveReader);
        }
        else if (NS_tstrcmp(token, NS_T("add-if")) == 0)   // Add if exists
        {
            action = new AddIfFile(archiveReader);
        }
        else if (NS_tstrcmp(token, NS_T("add-if-not")) == 0)   // Add if not exists
        {
            action = new AddIfNotFile(archiveReader);
        }
        else if (NS_tstrcmp(token, NS_T("patch-if")) == 0)   // Patch if exists
        {
            action = new PatchIfFile(archiveReader);
        }
        else
        {
            LOG(("DoUpdate: unknown token: " LOG_S, token));
            return PARSE_ERROR;
        }

        if (!action)
            return BAD_ACTION_ERROR;

        rv = action->Parse(line);
        if (rv)
            return rv;

        list.Append(action);
    }

    rv = list.Prepare();
    if (rv)
        return rv;

    rv = list.Execute();

    list.Finish(rv);
    return rv;
}