path: root/Source/exehead/util.c

/*
 * util.c
 * 
 * This file is a part of NSIS.
 * 
 * Copyright (C) 1999-2008 Nullsoft and Contributors
 * 
 * Licensed under the zlib/libpng license (the "License");
 * you may not use this file except in compliance with the License.
 * 
 * Licence details can be found in the file COPYING.
 * 
 * This software is provided 'as-is', without any express or implied
 * warranty.
 */

#include "../Platform.h"
#include <shellapi.h>
#include "util.h"
#include "state.h"
#include "config.h"
#include "lang.h"
#include "fileform.h"
#include "exec.h"
#include "ui.h"
#include "resource.h"

#ifdef NSIS_CONFIG_LOG
#if !defined(NSIS_CONFIG_LOG_ODS) && !defined(NSIS_CONFIG_LOG_STDOUT)
char g_log_file[1024];
#endif
#endif

// *** DO NOT DECLARE MORE VARIABLES INSIDE THIS PRAGMAS ***
// This will produce a special section called ".ndata" (stands for nsis data)
// this way makensis during build time, can search for this section by name
// and change the virtual size of this section
// which result in extra memory for extra variables without code to do allocation :)
// nsis then removes the "DISCARDABLE" style from section (for safe)
#ifdef _MSC_VER
#  pragma bss_seg(NSIS_VARS_SECTION)
NSIS_STRING g_usrvars[1];
#  pragma bss_seg()
#  pragma comment(linker, "/section:" NSIS_VARS_SECTION ",rwd")
#else
#  ifdef __GNUC__
NSIS_STRING g_usrvars[1] __attribute__((section (NSIS_VARS_SECTION)));
#  else
#    error Unknown compiler. You must implement the seperate PE section yourself.
#  endif
#endif

HANDLE NSISCALL myCreateProcess(char *cmd)
{
  PROCESS_INFORMATION ProcInfo;
  static STARTUPINFO StartUp;
  StartUp.cb=sizeof(StartUp);
  if (!CreateProcess(NULL, cmd, NULL, NULL, FALSE, 0, NULL, NULL, &StartUp, &ProcInfo))
    return NULL;
  CloseHandle(ProcInfo.hThread);
  return ProcInfo.hProcess;
}

/*BOOL NSISCALL my_SetWindowText(HWND hWnd, const char *val)
{
  return SendMessage(hWnd,WM_SETTEXT,0,(LPARAM)val);
}*/

BOOL NSISCALL my_SetDialogItemText(HWND dlg, UINT idx, const char *val)
{
  return SetDlgItemText(dlg,idx,val);
//  return my_SetWindowText(GetDlgItem(dlg, idx), val);
}

int NSISCALL my_GetDialogItemText(UINT idx, char *val)
{
  extern HWND m_curwnd;
  return GetDlgItemText(m_curwnd, idx, val, NSIS_MAX_STRLEN);
//  return my_GetWindowText(GetDlgItem(m_curwnd, idx), val, NSIS_MAX_STRLEN);
}

int NSISCALL my_MessageBox(const char *text, UINT type) {
  int _type = type & 0x001FFFFF;
  static MSGBOXPARAMS mbp = {
    sizeof(MSGBOXPARAMS),
    0,
    0,
    0,
    0,
    0,
    MAKEINTRESOURCE(IDI_ICON2),
    0,
    0,
    0
  };
  
#ifdef NSIS_CONFIG_SILENT_SUPPORT
  // default for silent installers
  if (g_exec_flags.silent && type >> 21)
    return type >> 21;
#endif
  // no silent or no default, just show
  if (g_exec_flags.rtl)
    _type ^= MB_RIGHT | MB_RTLREADING;

  mbp.hwndOwner = g_hwnd;
  mbp.hInstance = g_hInstance;
  mbp.lpszText = text;
  mbp.lpszCaption = g_caption;
  mbp.dwStyle = _type;
  
  return MessageBoxIndirect(&mbp);
}

void NSISCALL myDelete(char *buf, int flags)
{
  static char lbuf[NSIS_MAX_STRLEN];

  HANDLE h;
  WIN32_FIND_DATA fd;
  char *fn;
  int valid_dir=is_valid_instpath(buf);

  if ((flags & DEL_SIMPLE))
  {
    g_exec_flags.exec_error += !DeleteFile(buf);
    return;
  }

#ifdef NSIS_SUPPORT_RMDIR
  if (!(flags & DEL_DIR) || (valid_dir && (flags & DEL_RECURSE)))
#endif//NSIS_SUPPORT_RMDIR
  {
    mystrcpy(lbuf,buf);
#ifdef NSIS_SUPPORT_RMDIR
    if (flags & DEL_DIR)
      mystrcat(lbuf,"\\*.*");
    else
#endif//NSIS_SUPPORT_RMDIR
      trimslashtoend(buf);

    // only append backslash if the path isn't relative to the working directory [bug #1851273]
    if (*buf || *lbuf == '\\')
      mystrcat(buf,"\\");

    fn=buf+mystrlen(buf);

    h = FindFirstFile(lbuf,&fd);
    if (h != INVALID_HANDLE_VALUE)
    {
      do
      {
        char *fdfn = fd.cFileName;
        if (*findchar(fdfn, '?') && *fd.cAlternateFileName)
          // name contains unicode, use short name
          fdfn = fd.cAlternateFileName;

#ifdef NSIS_SUPPORT_RMDIR
        if (fdfn[0] == '.' && !fdfn[1]) continue;
        if (fdfn[0] == '.' && fdfn[1] == '.' && !fdfn[2]) continue;
#endif//NSIS_SUPPORT_RMDIR
        {
          mystrcpy(fn,fdfn);
          if (fd.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)
          {
#ifdef NSIS_SUPPORT_RMDIR
            if ((flags & (DEL_DIR | DEL_RECURSE)) == (DEL_DIR | DEL_RECURSE))
            {
              myDelete(buf,flags);
            }
#endif//NSIS_SUPPORT_RMDIR
          }
          else
          {
            log_printf2("Delete: DeleteFile(\"%s\")",buf);
            remove_ro_attr(buf);
            if (!DeleteFile(buf))
            {
#ifdef NSIS_SUPPORT_MOVEONREBOOT
              if (flags & DEL_REBOOT)
              {
                log_printf2("Delete: DeleteFile on Reboot(\"%s\")",buf);
                update_status_text(LANG_DELETEONREBOOT,buf);
                MoveFileOnReboot(buf,NULL);
              }
              else
#endif//NSIS_SUPPORT_MOVEONREBOOT
              {
                log_printf2("Delete: DeleteFile failed(\"%s\")",buf);
                g_exec_flags.exec_error++;
              }
            }
            else
              update_status_text(LANG_DELETEFILE,buf);
          }
        }
      } while (FindNextFile(h,&fd));
      FindClose(h);
    }

#ifdef NSIS_SUPPORT_RMDIR
    if (flags & DEL_DIR)
      fn[-1]=0;
#endif//NSIS_SUPPORT_RMDIR
  }

#ifdef NSIS_SUPPORT_RMDIR
  if ((flags & DEL_DIR))
  {
    if (!valid_dir)
    {
      log_printf2("RMDir: RemoveDirectory invalid input(\"%s\")",buf);
      g_exec_flags.exec_error++;
    }
    else if (file_exists(buf))
    {
      addtrailingslash(buf);
      log_printf2("RMDir: RemoveDirectory(\"%s\")",buf);
      remove_ro_attr(buf);
      if (!RemoveDirectory(buf))
      {
#ifdef NSIS_SUPPORT_MOVEONREBOOT
        if (flags & DEL_REBOOT)
        {
          log_printf2("RMDir: RemoveDirectory on Reboot(\"%s\")",buf);
          update_status_text(LANG_DELETEONREBOOT,buf);
          MoveFileOnReboot(buf,NULL);
        }
        else
#endif//NSIS_SUPPORT_MOVEONREBOOT
        {
          log_printf2("RMDir: RemoveDirectory failed(\"%s\")",buf);
          g_exec_flags.exec_error++;
        }
      }
      else
      {
        update_status_text(LANG_REMOVEDIR,buf);
      }
    }
  }
#endif//NSIS_SUPPORT_RMDIR
}

char *NSISCALL addtrailingslash(char *str)
{
  if (lastchar(str)!='\\') mystrcat(str,"\\");
  return str;
}

/*char NSISCALL lastchar(const char *str)
{
  return *CharPrev(str,str+mystrlen(str));
}*/

char * NSISCALL findchar(char *str, char c)
{
  while (*str && *str != c)
  {
    str = CharNext(str);
  }
  return str;
}

char * NSISCALL trimslashtoend(char *buf)
{
  char *p = buf + mystrlen(buf);
  do
  {
    if (*p == '\\')
      break;
    p = CharPrev(buf, p);
  } while (p > buf);

  *p = 0;

  return p + 1;
}

int NSISCALL validpathspec(char *ubuf)
{
  char dl = ubuf[0] | 0x20; // convert alleged drive letter to lower case
  return ((*(WORD*)ubuf==CHAR2_TO_WORD('\\','\\')) || (dl >= 'a' && dl <= 'z' && ubuf[1]==':'));
}

char * NSISCALL skip_root(char *path)
{
  char *p = CharNext(path);
  char *p2 = CharNext(p);

  if (*path && *(WORD*)p == CHAR2_TO_WORD(':', '\\'))
  {
    return CharNext(p2);
  }
  else if (*(WORD*)path == CHAR2_TO_WORD('\\','\\'))
  {
    // skip host and share name
    int x = 2;
    while (x--)
    {
      p2 = findchar(p2, '\\');
      if (!*p2)
        return NULL;
      p2++; // skip backslash
    }

    return p2;
  }
  else
    return NULL;
}

int NSISCALL is_valid_instpath(char *s)
{
  static char tmp[NSIS_MAX_STRLEN];
  char *root;

  mystrcpy(tmp, s);

  root = skip_root(tmp);

  if (!root)
    return 0;

  // must be called after skip_root or AllowRootDirInstall won't work.
  // validate_filename removes trailing blackslashes and so converts
  // "C:\" to "C:" which is not a valid directory. skip_root returns
  // NULL for "C:" so the above test returns 0.
  // validate_filename is called so directories such as "C:\ " will
  // not pass as a valid non-root directory.
  validate_filename(root);

  if ((g_flags & CH_FLAGS_NO_ROOT_DIR) && (!*root || *root == '\\'))
    return 0;

  while (mystrlen(tmp) > root - tmp)
  {
    WIN32_FIND_DATA *fd = file_exists(tmp);
    // if the directory bit not set then it's a file, which is not a valid inst dir...
    // GetFileAttributes is not used because it doesn't work with certain files (error 32)
    // as for concerns of the user using * or ?, that's invalid anyway...
    if (fd && !(fd->dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY))
      return 0;
    trimslashtoend(tmp);
  }

  // if the root drive exists
  addtrailingslash(tmp); // don't check the current directory, check the root directory
  if (GetFileAttributes(tmp) == INVALID_FILE_ATTRIBUTES)
    return 0;

  return 1;
}

char * NSISCALL mystrstri(char *a, const char *b)
{
  int l = mystrlen(b);
  while (mystrlen(a) >= l)
  {
    char c = a[l];
    a[l] = 0;
    if (!lstrcmpi(a, b))
    {
      a[l] = c;
      return a;
    }
    a[l] = c;
    a = CharNext(a);
  }
  return NULL;
}

void NSISCALL mini_memcpy(void *out, const void *in, int len)
{
  char *c_out=(char*)out;
  char *c_in=(char *)in;
  while (len-- > 0)
  {
    *c_out++=*c_in++;
  }
}

void NSISCALL remove_ro_attr(char *file)
{
  int attr = GetFileAttributes(file);
  if (attr != INVALID_FILE_ATTRIBUTES)
    SetFileAttributes(file,attr&(~FILE_ATTRIBUTE_READONLY));
}

HANDLE NSISCALL myOpenFile(const char *fn, DWORD da, DWORD cd)
{
  int attr = GetFileAttributes(fn);
  return CreateFile(
    fn,
    da,
    FILE_SHARE_READ,
    NULL,
    cd,
    attr == INVALID_FILE_ATTRIBUTES ? 0 : attr,
    NULL
  );
}

char * NSISCALL my_GetTempFileName(char *buf, const char *dir)
{
  int n = 100;
  while (n--)
  {
    char prefix[4];
    *(LPDWORD)prefix = CHAR4_TO_DWORD('n', 's', 'a', 0);
    prefix[2] += (char)(GetTickCount() % 26);
    if (GetTempFileName(dir, prefix, 0, buf))
      return buf;
  }
  *buf = 0;
  return 0;
}

#ifdef NSIS_SUPPORT_MOVEONREBOOT
void NSISCALL MoveFileOnReboot(LPCTSTR pszExisting, LPCTSTR pszNew)
{
  BOOL fOk = 0;
  typedef BOOL (WINAPI *mfea_t)(LPCSTR lpExistingFileName,LPCSTR lpNewFileName,DWORD dwFlags);
  mfea_t mfea;
  mfea=(mfea_t) myGetProcAddress(MGA_MoveFileExA);
  if (mfea)
  {
    fOk=mfea(pszExisting, pszNew, MOVEFILE_DELAY_UNTIL_REBOOT|MOVEFILE_REPLACE_EXISTING);
  }

  if (!fOk)
  {
    static char szRenameLine[1024];
    static char wininit[1024];
    static char tmpbuf[1024];
    int cchRenameLine;
    static const char szRenameSec[] = "[Rename]\r\n";
    HANDLE hfile;
    DWORD dwFileSize;
    DWORD dwBytes;
    DWORD dwRenameLinePos;
    char *pszWinInit;

    int spn;

    *(DWORD*)tmpbuf = CHAR4_TO_DWORD('N', 'U', 'L', 0);

    if (pszNew) {
      // create the file if it's not already there to prevent GetShortPathName from failing
      CloseHandle(myOpenFile(pszNew,0,CREATE_NEW));
      spn = GetShortPathName(pszNew,tmpbuf,1024);
      if (!spn || spn > 1024)
        return;
    }
    // wininit is used as a temporary here
    spn = GetShortPathName(pszExisting,wininit,1024);
    if (!spn || spn > 1024)
      return;
    cchRenameLine = wsprintf(szRenameLine,"%s=%s\r\n",tmpbuf,wininit);

    GetNSISString(wininit, g_header->str_wininit);
    hfile = myOpenFile(wininit, GENERIC_READ | GENERIC_WRITE, OPEN_ALWAYS);

    if (hfile != INVALID_HANDLE_VALUE)
    {
      dwFileSize = GetFileSize(hfile, NULL);
      pszWinInit = GlobalAlloc(GPTR, dwFileSize + cchRenameLine + 10);

      if (pszWinInit != NULL)
      {
        if (ReadFile(hfile, pszWinInit, dwFileSize, &dwBytes, NULL) && dwFileSize == dwBytes)
        {
          LPSTR pszRenameSecInFile = mystrstri(pszWinInit, szRenameSec);
          if (pszRenameSecInFile == NULL)
          {
            mystrcpy(pszWinInit+dwFileSize, szRenameSec);
            dwFileSize += 10;
            dwRenameLinePos = dwFileSize;
          }
          else
          {
            char *pszFirstRenameLine = pszRenameSecInFile+10;
            char *pszNextSec = mystrstri(pszFirstRenameLine,"\n[");
            if (pszNextSec)
            {
              char *p = ++pszNextSec;
              while (p < pszWinInit + dwFileSize) {
                p[cchRenameLine] = *p;
                p++;
              }

              dwRenameLinePos = pszNextSec - pszWinInit;
            }
            // rename section is last, stick item at end of file
            else dwRenameLinePos = dwFileSize;
          }

          mini_memcpy(&pszWinInit[dwRenameLinePos], szRenameLine, cchRenameLine);
          dwFileSize += cchRenameLine;

          SetFilePointer(hfile, 0, NULL, FILE_BEGIN);
          WriteFile(hfile, pszWinInit, dwFileSize, &dwBytes, NULL);

          GlobalFree(pszWinInit);
        }
      }
      
      CloseHandle(hfile);
    }
  }

#ifdef NSIS_SUPPORT_REBOOT
  g_exec_flags.exec_reboot++;
#endif
}
#endif

void NSISCALL myRegGetStr(HKEY root, const char *sub, const char *name, char *out, int x64)
{
  HKEY hKey;
  *out=0;
  if (RegOpenKeyEx(root,sub,0,KEY_READ|(x64?KEY_WOW64_64KEY:0),&hKey) == ERROR_SUCCESS)
  {
    DWORD l = NSIS_MAX_STRLEN;
    DWORD t;
    if (RegQueryValueEx(hKey,name,NULL,&t,out,&l ) != ERROR_SUCCESS || (t != REG_SZ && t != REG_EXPAND_SZ)) *out=0;
    out[NSIS_MAX_STRLEN-1]=0;
    RegCloseKey(hKey);
  }
}

void NSISCALL myitoa(char *s, int d)
{
  static const char c[] = "%d";
  wsprintf(s,c,d);
}

int NSISCALL myatoi(char *s)
{
  unsigned int v=0;
  int sign=1; // sign of positive
  char m=10; // base of 10
  char t='9'; // cap top of numbers at 9

  if (*s == '-')
  {
    s++;  //skip over -
    sign=-1; // sign flip
  }

  if (*s == '0')
  {
    s++; // skip over 0
    if (s[0] >= '0' && s[0] <= '7')
    {
      m=8; // base of 8
      t='7'; // cap top at 7
    }
    if ((s[0] & ~0x20) == 'X')
    {
      m=16; // base of 16
      s++; // advance over 'x'
    }
  }

  for (;;)
  {
    int c=*s++;
    if (c >= '0' && c <= t) c-='0';
    else if (m==16 && (c & ~0x20) >= 'A' && (c & ~0x20) <= 'F') c = (c & 7) + 9;
    else break;
    v*=m;
    v+=c;
  }
  return ((int)v)*sign;
}

// Straight copies of selected shell functions.  Calling local functions
// requires less code than DLL functions.  For the savings to outweigh the cost
// of a new function there should be about a couple of dozen or so calls.
char * NSISCALL mystrcpy(char *out, const char *in)
{
  return lstrcpyn(out, in, NSIS_MAX_STRLEN);
}

int NSISCALL mystrlen(const char *in)
{
  return lstrlen(in);
}

char * NSISCALL mystrcat(char *out, const char *concat)
{
  return lstrcat(out, concat);
}

char ps_tmpbuf[NSIS_MAX_STRLEN*2];

const char SYSREGKEY[]   = "Software\\Microsoft\\Windows\\CurrentVersion";
const char QUICKLAUNCH[] = "\\Microsoft\\Internet Explorer\\Quick Launch";

typedef HRESULT (__stdcall * PFNSHGETFOLDERPATHA)(HWND, int, HANDLE, DWORD, LPSTR);
extern void *g_SHGetFolderPath;

// Based on Dave Laundon's simplified process_string
char * NSISCALL GetNSISString(char *outbuf, int strtab)
{
  char *in = (char*)GetNSISStringNP(GetNSISTab(strtab));
  char *out = ps_tmpbuf;
  if ((unsigned int) (outbuf - ps_tmpbuf) < sizeof(ps_tmpbuf))
  {
    out = outbuf;
    outbuf = 0;
  }
  while (*in && out - ps_tmpbuf < NSIS_MAX_STRLEN)
  {
    unsigned char nVarIdx = (unsigned char)*in++;
    int nData;
    int fldrs[4];
    if (nVarIdx > NS_CODES_START)
    {
      nData = ((in[1] & 0x7F) << 7) | (in[0] & 0x7F);
      fldrs[0] = in[0]; // current user
      fldrs[1] = in[0] | CSIDL_FLAG_CREATE;
      fldrs[2] = in[1]; // all users
      fldrs[3] = in[1] | CSIDL_FLAG_CREATE;
      in += 2;

      if (nVarIdx == NS_SHELL_CODE)
      {
        LPITEMIDLIST idl;

        int x = 2;
        DWORD ver = GetVersion();

        /*

        SHGetFolderPath as provided by shfolder.dll is used to get special folders
        unless the installer is running on Windows 95/98. For 95/98 shfolder.dll is
        only used for the Application Data and Documents folder (if the DLL exists).
        Oherwise, the old SHGetSpecialFolderLocation API is called.

        There reason for not using shfolder.dll for all folders on 95/98 is that
        some unsupported folders (such as the Start Menu folder for all users) are
        simulated instead of returning an error so whe can fall back on the folder
        for the current user.

        SHGetFolderPath in shell32.dll could be called directly for Windows versions
        later than 95/98 but there is no need to do so, because shfolder.dll is still
        provided and calls shell32.dll.

        */

        BOOL use_shfolder =
          // Use shfolder if not on 95/98
          !((ver & 0x80000000) && (LOWORD(ver) != 0x5A04)) ||

          // Unless the Application Data or Documents folder is requested
          (
            (fldrs[2] == CSIDL_COMMON_APPDATA) ||
            (fldrs[2] == CSIDL_COMMON_DOCUMENTS)
          );

        /* Carry on... shfolder stuff is over. */

        if (g_exec_flags.all_user_var)
        {
          x = 4;
        }

        if (fldrs[0] & 0x80)
        {
          myRegGetStr(HKEY_LOCAL_MACHINE, SYSREGKEY, GetNSISStringNP(fldrs[0] & 0x3F), out, fldrs[0] & 0x40);
          if (!*out)
            GetNSISString(out, fldrs[2]);
          x = 0;
        }
        else if (fldrs[0] == CSIDL_SYSTEM)
        {
          GetSystemDirectory(out, NSIS_MAX_STRLEN);
          x = 0;
        }
        else if (fldrs[0] == CSIDL_WINDOWS)
        {
          GetWindowsDirectory(out, NSIS_MAX_STRLEN);
          x = 0;
        }

        while (x--)
        {
          if (g_SHGetFolderPath && use_shfolder)
          {
            PFNSHGETFOLDERPATHA SHGetFolderPathFunc = (PFNSHGETFOLDERPATHA) g_SHGetFolderPath;
            if (!SHGetFolderPathFunc(g_hwnd, fldrs[x], NULL, SHGFP_TYPE_CURRENT, out))
            {
              break;
            }
          }
            
          if (!SHGetSpecialFolderLocation(g_hwnd, fldrs[x], &idl))
          {
            BOOL res = SHGetPathFromIDList(idl, out);
            CoTaskMemFree(idl);
            if (res) break;
          }

          *out=0;
        }

        if (*out)
        {
          // all users' version is CSIDL_APPDATA only for $QUICKLAUNCH
          // for normal $APPDATA, it'd be CSIDL_APPDATA_COMMON
          if (fldrs[2] == CSIDL_APPDATA)
          {
            mystrcat(out, QUICKLAUNCH);
          }
        }
        validate_filename(out);
      }
      else if (nVarIdx == NS_VAR_CODE)
      {
        if (nData == 29) // $HWNDPARENT
          myitoa(out, (unsigned int) g_hwnd);
        else
          mystrcpy(out, g_usrvars[nData]);
        // validate the directory name
        if ((unsigned int)(nData - 21) < 7) {
          // validate paths for $INSTDIR, $OUTDIR, $EXEDIR, $LANGUAGE, $TEMP, $PLUGINSDIR and $EXEPATH
          // $LANGUAGE is just a number anyway...
          validate_filename(out);
        }
      } // == VAR_CODES_START
      else if (nVarIdx == NS_LANG_CODE)
      {
        GetNSISString(out, -nData-1);
      }
      out += mystrlen(out);
    }
    else if (nVarIdx == NS_SKIP_CODE)
    {
      *out++ = *in++;
    }
    else // Normal char
    {
      *out++ = nVarIdx;
    }
  } // while
  *out = 0;
  if (outbuf)
    return mystrcpy(outbuf, ps_tmpbuf);
  return ps_tmpbuf;
}

void NSISCALL validate_filename(char *in) {
  char *nono = "*?|<>/\":";
  char *out;
  char *out_save;

  // ignoring spaces is wrong, " C:\blah" is invalid
  //while (*in == ' ') in = CharNext(in);

  if (in[0] == '\\' && in[1] == '\\' && in[2] == '?' && in[3] == '\\')
  {
    // at least four bytes
    in += 4;
  }
  if (*in)
  {
    // at least two bytes
    if (validpathspec(in)) in += 2;
  }
  out = out_save = in;
  while (*in)
  {
    if ((unsigned char)*in > 31 && !*findchar(nono, *in))
    {
      mini_memcpy(out, in, CharNext(in) - in);
      out = CharNext(out);
    }
    in = CharNext(in);
  }
  *out = 0;
  do
  {
    out = CharPrev(out_save, out);
    if (*out == ' ' || *out == '\\')
      *out = 0;
    else
      break;
  } while (out_save < out);
}

#ifdef NSIS_CONFIG_LOG
int log_dolog;
char log_text[2048]; // 1024 for each wsprintf

#if !defined(NSIS_CONFIG_LOG_ODS) && !defined(NSIS_CONFIG_LOG_STDOUT)
void NSISCALL log_write(int close)
{
  static HANDLE fp=INVALID_HANDLE_VALUE;
  if (close)
  {
    if (fp!=INVALID_HANDLE_VALUE)
    {
      CloseHandle(fp);
    }
    fp=INVALID_HANDLE_VALUE;
    return;
  }
  if (log_dolog)
  {
    if (g_log_file[0] && fp==INVALID_HANDLE_VALUE)
    {
      fp = myOpenFile(g_log_file,GENERIC_WRITE,OPEN_ALWAYS);
      if (fp!=INVALID_HANDLE_VALUE)
        SetFilePointer(fp,0,NULL,FILE_END);
    }
    if (fp!=INVALID_HANDLE_VALUE)
    {
      DWORD d;
      mystrcat(log_text,"\r\n");
      WriteFile(fp,log_text,mystrlen(log_text),&d,NULL);
    }
  }
}
#endif//!NSIS_CONFIG_LOG_ODS && !NSIS_CONFIG_LOG_STDOUT

const char * _RegKeyHandleToName(HKEY hKey)
{
  if (hKey == HKEY_CLASSES_ROOT)
    return "HKEY_CLASSES_ROOT";
  else if (hKey == HKEY_CURRENT_USER)
    return "HKEY_CURRENT_USER";
  else if (hKey == HKEY_LOCAL_MACHINE)
    return "HKEY_LOCAL_MACHINE";
  else if (hKey == HKEY_USERS)
    return "HKEY_USERS";
  else if (hKey == HKEY_PERFORMANCE_DATA)
    return "HKEY_PERFORMANCE_DATA";
  else if (hKey == HKEY_CURRENT_CONFIG)
    return "HKEY_CURRENT_CONFIG";
  else if (hKey == HKEY_DYN_DATA)
    return "HKEY_DYN_DATA";
  else
    return "invalid registry key";
}

void _LogData2Hex(char *buf, size_t buflen, unsigned char *data, size_t datalen)
{
  char *p = buf;

  size_t i;

  int dots = 0;
  size_t bufbytes = buflen / 3; // 2 hex digits, one space/null

  if (datalen > bufbytes)
  {
    bufbytes--;
    dots = 1;
  }
  else
    bufbytes = datalen;

  for (i = 0; i < bufbytes; i++)
  {
    wsprintf(p, "%02x%c", data[i], (i == bufbytes - 1) ? '\0' : ' ');
    p += 3;
  }

  if (dots)
    mystrcat(buf, "...");
}

#ifdef NSIS_CONFIG_LOG_TIMESTAMP
void log_timestamp(char *buf)
{
  SYSTEMTIME st;
  GetLocalTime(&st);
  wsprintf(buf,"[%04hu/%02hu/%02hu %02hu:%02hu:%02hu] ", st.wYear, st.wMonth, st.wDay, st.wHour, st.wMinute, st.wSecond);
}
#else
#  define log_timestamp(x)
#endif//NSIS_CONFIG_LOG_TIMESTAMP

void log_printf(char *format, ...)
{
  va_list val;
  va_start(val,format);

  log_text[0] = '\0';
  log_timestamp(log_text);
  wvsprintf(log_text+mystrlen(log_text),format,val);

  va_end(val);
#ifdef NSIS_CONFIG_LOG_ODS
  if (log_dolog)
    OutputDebugString(log_text);
#endif
#ifdef NSIS_CONFIG_LOG_STDOUT
  if (log_dolog && GetStdHandle(STD_OUTPUT_HANDLE) != INVALID_HANDLE_VALUE)
  {
    DWORD dwBytes;
    WriteFile(GetStdHandle(STD_OUTPUT_HANDLE), log_text, lstrlen(log_text), &dwBytes, NULL);
    WriteFile(GetStdHandle(STD_OUTPUT_HANDLE), "\n", 1, &dwBytes, NULL);
  }
#endif
#if !defined(NSIS_CONFIG_LOG_ODS) && !defined(NSIS_CONFIG_LOG_STDOUT)
  log_write(0);
#endif
}
#endif//NSIS_CONFIG_LOG

WIN32_FIND_DATA * NSISCALL file_exists(char *buf)
{
  HANDLE h;
  static WIN32_FIND_DATA fd;
  h = FindFirstFile(buf,&fd);
  if (h != INVALID_HANDLE_VALUE)
  {
    FindClose(h);
    return &fd;
  }
  return NULL;
}

struct MGA_FUNC
{
  const char *dll;
  const char *func;
};

struct MGA_FUNC MGA_FUNCS[] = {
  {"KERNEL32", "GetDiskFreeSpaceExA"},
  {"KERNEL32", "MoveFileExA"},
  {"ADVAPI32", "RegDeleteKeyExA"},
  {"ADVAPI32", "OpenProcessToken"},
  {"ADVAPI32", "LookupPrivilegeValueA"},
  {"ADVAPI32", "AdjustTokenPrivileges"},
  {"KERNEL32", "GetUserDefaultUILanguage"},
  {"SHLWAPI",  "SHAutoComplete"},
  {"SHFOLDER", "SHGetFolderPathA"}
};

void * NSISCALL myGetProcAddress(const enum myGetProcAddressFunctions func)
{
  const char *dll = MGA_FUNCS[func].dll;
  HMODULE hModule = GetModuleHandle(dll);
  if (!hModule)
    hModule = LoadLibrary(dll);
  if (!hModule)
    return NULL;

  return GetProcAddress(hModule, MGA_FUNCS[func].func);
}

void NSISCALL MessageLoop(UINT uCheckedMsg)
{
  MSG msg;
  while (PeekMessage(&msg, NULL, uCheckedMsg, uCheckedMsg, PM_REMOVE))
    DispatchMessage(&msg);
}